linux_dsm_epyc7002/drivers/usb/dwc2/hcd_queue.c

2016 lines
62 KiB
C
Raw Normal View History

// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
* hcd_queue.c - DesignWare HS OTG Controller host queuing routines
*
* Copyright (C) 2004-2013 Synopsys, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The names of the above-listed copyright holders may not be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* ALTERNATIVELY, this software may be distributed under the terms of the
* GNU General Public License ("GPL") as published by the Free Software
* Foundation; either version 2 of the License, or (at your option) any
* later version.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This file contains the functions to manage Queue Heads and Queue
* Transfer Descriptors for Host mode
*/
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
#include <linux/gcd.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/usb/ch11.h>
#include "core.h"
#include "hcd.h"
/* Wait this long before releasing periodic reservation */
#define DWC2_UNRESERVE_DELAY (msecs_to_jiffies(5))
/**
* dwc2_periodic_channel_available() - Checks that a channel is available for a
* periodic transfer
*
* @hsotg: The HCD state structure for the DWC OTG controller
*
* Return: 0 if successful, negative error code otherwise
*/
static int dwc2_periodic_channel_available(struct dwc2_hsotg *hsotg)
{
/*
* Currently assuming that there is a dedicated host channel for
* each periodic transaction plus at least one host channel for
* non-periodic transactions
*/
int status;
int num_channels;
num_channels = hsotg->params.host_channels;
if ((hsotg->periodic_channels + hsotg->non_periodic_channels <
num_channels) && (hsotg->periodic_channels < num_channels - 1)) {
status = 0;
} else {
dev_dbg(hsotg->dev,
"%s: Total channels: %d, Periodic: %d, Non-periodic: %d\n",
__func__, num_channels,
hsotg->periodic_channels, hsotg->non_periodic_channels);
status = -ENOSPC;
}
return status;
}
/**
* dwc2_check_periodic_bandwidth() - Checks that there is sufficient bandwidth
* for the specified QH in the periodic schedule
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: QH containing periodic bandwidth required
*
* Return: 0 if successful, negative error code otherwise
*
* For simplicity, this calculation assumes that all the transfers in the
* periodic schedule may occur in the same (micro)frame
*/
static int dwc2_check_periodic_bandwidth(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh)
{
int status;
s16 max_claimed_usecs;
status = 0;
if (qh->dev_speed == USB_SPEED_HIGH || qh->do_split) {
/*
* High speed mode
* Max periodic usecs is 80% x 125 usec = 100 usec
*/
max_claimed_usecs = 100 - qh->host_us;
} else {
/*
* Full speed mode
* Max periodic usecs is 90% x 1000 usec = 900 usec
*/
max_claimed_usecs = 900 - qh->host_us;
}
if (hsotg->periodic_usecs > max_claimed_usecs) {
dev_err(hsotg->dev,
"%s: already claimed usecs %d, required usecs %d\n",
__func__, hsotg->periodic_usecs, qh->host_us);
status = -ENOSPC;
}
return status;
}
/**
* pmap_schedule() - Schedule time in a periodic bitmap (pmap).
*
* @map: The bitmap representing the schedule; will be updated
* upon success.
* @bits_per_period: The schedule represents several periods. This is how many
* bits are in each period. It's assumed that the beginning
* of the schedule will repeat after its end.
* @periods_in_map: The number of periods in the schedule.
* @num_bits: The number of bits we need per period we want to reserve
* in this function call.
* @interval: How often we need to be scheduled for the reservation this
* time. 1 means every period. 2 means every other period.
* ...you get the picture?
* @start: The bit number to start at. Normally 0. Must be within
* the interval or we return failure right away.
* @only_one_period: Normally we'll allow picking a start anywhere within the
* first interval, since we can still make all repetition
* requirements by doing that. However, if you pass true
* here then we'll return failure if we can't fit within
* the period that "start" is in.
*
* The idea here is that we want to schedule time for repeating events that all
* want the same resource. The resource is divided into fixed-sized periods
* and the events want to repeat every "interval" periods. The schedule
* granularity is one bit.
*
* To keep things "simple", we'll represent our schedule with a bitmap that
* contains a fixed number of periods. This gets rid of a lot of complexity
* but does mean that we need to handle things specially (and non-ideally) if
* the number of the periods in the schedule doesn't match well with the
* intervals that we're trying to schedule.
*
* Here's an explanation of the scheme we'll implement, assuming 8 periods.
* - If interval is 1, we need to take up space in each of the 8
* periods we're scheduling. Easy.
* - If interval is 2, we need to take up space in half of the
* periods. Again, easy.
* - If interval is 3, we actually need to fall back to interval 1.
* Why? Because we might need time in any period. AKA for the
* first 8 periods, we'll be in slot 0, 3, 6. Then we'll be
* in slot 1, 4, 7. Then we'll be in 2, 5. Then we'll be back to
* 0, 3, and 6. Since we could be in any frame we need to reserve
* for all of them. Sucks, but that's what you gotta do. Note that
* if we were instead scheduling 8 * 3 = 24 we'd do much better, but
* then we need more memory and time to do scheduling.
* - If interval is 4, easy.
* - If interval is 5, we again need interval 1. The schedule will be
* 0, 5, 2, 7, 4, 1, 6, 3, 0
* - If interval is 6, we need interval 2. 0, 6, 4, 2.
* - If interval is 7, we need interval 1.
* - If interval is 8, we need interval 8.
*
* If you do the math, you'll see that we need to pretend that interval is
* equal to the greatest_common_divisor(interval, periods_in_map).
*
* Note that at the moment this function tends to front-pack the schedule.
* In some cases that's really non-ideal (it's hard to schedule things that
* need to repeat every period). In other cases it's perfect (you can easily
* schedule bigger, less often repeating things).
*
* Here's the algorithm in action (8 periods, 5 bits per period):
* |** | |** | |** | |** | | OK 2 bits, intv 2 at 0
* |*****| ***|*****| ***|*****| ***|*****| ***| OK 3 bits, intv 3 at 2
* |*****|* ***|*****| ***|*****|* ***|*****| ***| OK 1 bits, intv 4 at 5
* |** |* |** | |** |* |** | | Remv 3 bits, intv 3 at 2
* |*** |* |*** | |*** |* |*** | | OK 1 bits, intv 6 at 2
* |**** |* * |**** | * |**** |* * |**** | * | OK 1 bits, intv 1 at 3
* |**** |**** |**** | *** |**** |**** |**** | *** | OK 2 bits, intv 2 at 6
* |*****|*****|*****| ****|*****|*****|*****| ****| OK 1 bits, intv 1 at 4
* |*****|*****|*****| ****|*****|*****|*****| ****| FAIL 1 bits, intv 1
* | ***|*****| ***| ****| ***|*****| ***| ****| Remv 2 bits, intv 2 at 0
* | ***| ****| ***| ****| ***| ****| ***| ****| Remv 1 bits, intv 4 at 5
* | **| ****| **| ****| **| ****| **| ****| Remv 1 bits, intv 6 at 2
* | *| ** *| *| ** *| *| ** *| *| ** *| Remv 1 bits, intv 1 at 3
* | *| *| *| *| *| *| *| *| Remv 2 bits, intv 2 at 6
* | | | | | | | | | Remv 1 bits, intv 1 at 4
* |** | |** | |** | |** | | OK 2 bits, intv 2 at 0
* |*** | |** | |*** | |** | | OK 1 bits, intv 4 at 2
* |*****| |** **| |*****| |** **| | OK 2 bits, intv 2 at 3
* |*****|* |** **| |*****|* |** **| | OK 1 bits, intv 4 at 5
* |*****|*** |** **| ** |*****|*** |** **| ** | OK 2 bits, intv 2 at 6
* |*****|*****|** **| ****|*****|*****|** **| ****| OK 2 bits, intv 2 at 8
* |*****|*****|*****| ****|*****|*****|*****| ****| OK 1 bits, intv 4 at 12
*
* This function is pretty generic and could be easily abstracted if anything
* needed similar scheduling.
*
* Returns either -ENOSPC or a >= 0 start bit which should be passed to the
* unschedule routine. The map bitmap will be updated on a non-error result.
*/
static int pmap_schedule(unsigned long *map, int bits_per_period,
int periods_in_map, int num_bits,
int interval, int start, bool only_one_period)
{
int interval_bits;
int to_reserve;
int first_end;
int i;
if (num_bits > bits_per_period)
return -ENOSPC;
/* Adjust interval as per description */
interval = gcd(interval, periods_in_map);
interval_bits = bits_per_period * interval;
to_reserve = periods_in_map / interval;
/* If start has gotten us past interval then we can't schedule */
if (start >= interval_bits)
return -ENOSPC;
if (only_one_period)
/* Must fit within same period as start; end at begin of next */
first_end = (start / bits_per_period + 1) * bits_per_period;
else
/* Can fit anywhere in the first interval */
first_end = interval_bits;
/*
* We'll try to pick the first repetition, then see if that time
* is free for each of the subsequent repetitions. If it's not
* we'll adjust the start time for the next search of the first
* repetition.
*/
while (start + num_bits <= first_end) {
int end;
/* Need to stay within this period */
end = (start / bits_per_period + 1) * bits_per_period;
/* Look for num_bits us in this microframe starting at start */
start = bitmap_find_next_zero_area(map, end, start, num_bits,
0);
/*
* We should get start >= end if we fail. We might be
* able to check the next microframe depending on the
* interval, so continue on (start already updated).
*/
if (start >= end) {
start = end;
continue;
}
/* At this point we have a valid point for first one */
for (i = 1; i < to_reserve; i++) {
int ith_start = start + interval_bits * i;
int ith_end = end + interval_bits * i;
int ret;
/* Use this as a dumb "check if bits are 0" */
ret = bitmap_find_next_zero_area(
map, ith_start + num_bits, ith_start, num_bits,
0);
/* We got the right place, continue checking */
if (ret == ith_start)
continue;
/* Move start up for next time and exit for loop */
ith_start = bitmap_find_next_zero_area(
map, ith_end, ith_start, num_bits, 0);
if (ith_start >= ith_end)
/* Need a while new period next time */
start = end;
else
start = ith_start - interval_bits * i;
break;
}
/* If didn't exit the for loop with a break, we have success */
if (i == to_reserve)
break;
}
if (start + num_bits > first_end)
return -ENOSPC;
for (i = 0; i < to_reserve; i++) {
int ith_start = start + interval_bits * i;
bitmap_set(map, ith_start, num_bits);
}
return start;
}
/**
* pmap_unschedule() - Undo work done by pmap_schedule()
*
* @map: See pmap_schedule().
* @bits_per_period: See pmap_schedule().
* @periods_in_map: See pmap_schedule().
* @num_bits: The number of bits that was passed to schedule.
* @interval: The interval that was passed to schedule.
* @start: The return value from pmap_schedule().
*/
static void pmap_unschedule(unsigned long *map, int bits_per_period,
int periods_in_map, int num_bits,
int interval, int start)
{
int interval_bits;
int to_release;
int i;
/* Adjust interval as per description in pmap_schedule() */
interval = gcd(interval, periods_in_map);
interval_bits = bits_per_period * interval;
to_release = periods_in_map / interval;
for (i = 0; i < to_release; i++) {
int ith_start = start + interval_bits * i;
bitmap_clear(map, ith_start, num_bits);
}
}
/**
* dwc2_get_ls_map() - Get the map used for the given qh
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
*
* We'll always get the periodic map out of our TT. Note that even if we're
* running the host straight in low speed / full speed mode it appears as if
* a TT is allocated for us, so we'll use it. If that ever changes we can
* add logic here to get a map out of "hsotg" if !qh->do_split.
*
* Returns: the map or NULL if a map couldn't be found.
*/
static unsigned long *dwc2_get_ls_map(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh)
{
unsigned long *map;
/* Don't expect to be missing a TT and be doing low speed scheduling */
if (WARN_ON(!qh->dwc_tt))
return NULL;
/* Get the map and adjust if this is a multi_tt hub */
map = qh->dwc_tt->periodic_bitmaps;
if (qh->dwc_tt->usb_tt->multi)
map += DWC2_ELEMENTS_PER_LS_BITMAP * qh->ttport;
return map;
}
#ifdef DWC2_PRINT_SCHEDULE
/*
* cat_printf() - A printf() + strcat() helper
*
* This is useful for concatenating a bunch of strings where each string is
* constructed using printf.
*
* @buf: The destination buffer; will be updated to point after the printed
* data.
* @size: The number of bytes in the buffer (includes space for '\0').
* @fmt: The format for printf.
* @...: The args for printf.
*/
static __printf(3, 4)
void cat_printf(char **buf, size_t *size, const char *fmt, ...)
{
va_list args;
int i;
if (*size == 0)
return;
va_start(args, fmt);
i = vsnprintf(*buf, *size, fmt, args);
va_end(args);
if (i >= *size) {
(*buf)[*size - 1] = '\0';
*buf += *size;
*size = 0;
} else {
*buf += i;
*size -= i;
}
}
/*
* pmap_print() - Print the given periodic map
*
* Will attempt to print out the periodic schedule.
*
* @map: See pmap_schedule().
* @bits_per_period: See pmap_schedule().
* @periods_in_map: See pmap_schedule().
* @period_name: The name of 1 period, like "uFrame"
* @units: The name of the units, like "us".
* @print_fn: The function to call for printing.
* @print_data: Opaque data to pass to the print function.
*/
static void pmap_print(unsigned long *map, int bits_per_period,
int periods_in_map, const char *period_name,
const char *units,
void (*print_fn)(const char *str, void *data),
void *print_data)
{
int period;
for (period = 0; period < periods_in_map; period++) {
char tmp[64];
char *buf = tmp;
size_t buf_size = sizeof(tmp);
int period_start = period * bits_per_period;
int period_end = period_start + bits_per_period;
int start = 0;
int count = 0;
bool printed = false;
int i;
for (i = period_start; i < period_end + 1; i++) {
/* Handle case when ith bit is set */
if (i < period_end &&
bitmap_find_next_zero_area(map, i + 1,
i, 1, 0) != i) {
if (count == 0)
start = i - period_start;
count++;
continue;
}
/* ith bit isn't set; don't care if count == 0 */
if (count == 0)
continue;
if (!printed)
cat_printf(&buf, &buf_size, "%s %d: ",
period_name, period);
else
cat_printf(&buf, &buf_size, ", ");
printed = true;
cat_printf(&buf, &buf_size, "%d %s -%3d %s", start,
units, start + count - 1, units);
count = 0;
}
if (printed)
print_fn(tmp, print_data);
}
}
struct dwc2_qh_print_data {
struct dwc2_hsotg *hsotg;
struct dwc2_qh *qh;
};
/**
* dwc2_qh_print() - Helper function for dwc2_qh_schedule_print()
*
* @str: The string to print
* @data: A pointer to a struct dwc2_qh_print_data
*/
static void dwc2_qh_print(const char *str, void *data)
{
struct dwc2_qh_print_data *print_data = data;
dwc2_sch_dbg(print_data->hsotg, "QH=%p ...%s\n", print_data->qh, str);
}
/**
* dwc2_qh_schedule_print() - Print the periodic schedule
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH to print.
*/
static void dwc2_qh_schedule_print(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh)
{
struct dwc2_qh_print_data print_data = { hsotg, qh };
int i;
/*
* The printing functions are quite slow and inefficient.
* If we don't have tracing turned on, don't run unless the special
* define is turned on.
*/
if (qh->schedule_low_speed) {
unsigned long *map = dwc2_get_ls_map(hsotg, qh);
dwc2_sch_dbg(hsotg, "QH=%p LS/FS trans: %d=>%d us @ %d us",
qh, qh->device_us,
DWC2_ROUND_US_TO_SLICE(qh->device_us),
DWC2_US_PER_SLICE * qh->ls_start_schedule_slice);
if (map) {
dwc2_sch_dbg(hsotg,
"QH=%p Whole low/full speed map %p now:\n",
qh, map);
pmap_print(map, DWC2_LS_PERIODIC_SLICES_PER_FRAME,
DWC2_LS_SCHEDULE_FRAMES, "Frame ", "slices",
dwc2_qh_print, &print_data);
}
}
for (i = 0; i < qh->num_hs_transfers; i++) {
struct dwc2_hs_transfer_time *trans_time = qh->hs_transfers + i;
int uframe = trans_time->start_schedule_us /
DWC2_HS_PERIODIC_US_PER_UFRAME;
int rel_us = trans_time->start_schedule_us %
DWC2_HS_PERIODIC_US_PER_UFRAME;
dwc2_sch_dbg(hsotg,
"QH=%p HS trans #%d: %d us @ uFrame %d + %d us\n",
qh, i, trans_time->duration_us, uframe, rel_us);
}
if (qh->num_hs_transfers) {
dwc2_sch_dbg(hsotg, "QH=%p Whole high speed map now:\n", qh);
pmap_print(hsotg->hs_periodic_bitmap,
DWC2_HS_PERIODIC_US_PER_UFRAME,
DWC2_HS_SCHEDULE_UFRAMES, "uFrame", "us",
dwc2_qh_print, &print_data);
}
}
#else
static inline void dwc2_qh_schedule_print(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh) {};
#endif
/**
* dwc2_ls_pmap_schedule() - Schedule a low speed QH
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
* @search_slice: We'll start trying to schedule at the passed slice.
* Remember that slices are the units of the low speed
* schedule (think 25us or so).
*
* Wraps pmap_schedule() with the right parameters for low speed scheduling.
*
* Normally we schedule low speed devices on the map associated with the TT.
*
* Returns: 0 for success or an error code.
*/
static int dwc2_ls_pmap_schedule(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
int search_slice)
{
int slices = DIV_ROUND_UP(qh->device_us, DWC2_US_PER_SLICE);
unsigned long *map = dwc2_get_ls_map(hsotg, qh);
int slice;
if (!map)
return -EINVAL;
/*
* Schedule on the proper low speed map with our low speed scheduling
* parameters. Note that we use the "device_interval" here since
* we want the low speed interval and the only way we'd be in this
* function is if the device is low speed.
*
* If we happen to be doing low speed and high speed scheduling for the
* same transaction (AKA we have a split) we always do low speed first.
* That means we can always pass "false" for only_one_period (that
* parameters is only useful when we're trying to get one schedule to
* match what we already planned in the other schedule).
*/
slice = pmap_schedule(map, DWC2_LS_PERIODIC_SLICES_PER_FRAME,
DWC2_LS_SCHEDULE_FRAMES, slices,
qh->device_interval, search_slice, false);
if (slice < 0)
return slice;
qh->ls_start_schedule_slice = slice;
return 0;
}
/**
* dwc2_ls_pmap_unschedule() - Undo work done by dwc2_ls_pmap_schedule()
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
*/
static void dwc2_ls_pmap_unschedule(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh)
{
int slices = DIV_ROUND_UP(qh->device_us, DWC2_US_PER_SLICE);
unsigned long *map = dwc2_get_ls_map(hsotg, qh);
/* Schedule should have failed, so no worries about no error code */
if (!map)
return;
pmap_unschedule(map, DWC2_LS_PERIODIC_SLICES_PER_FRAME,
DWC2_LS_SCHEDULE_FRAMES, slices, qh->device_interval,
qh->ls_start_schedule_slice);
}
/**
* dwc2_hs_pmap_schedule - Schedule in the main high speed schedule
*
* This will schedule something on the main dwc2 schedule.
*
* We'll start looking in qh->hs_transfers[index].start_schedule_us. We'll
* update this with the result upon success. We also use the duration from
* the same structure.
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
* @only_one_period: If true we will limit ourselves to just looking at
* one period (aka one 100us chunk). This is used if we have
* already scheduled something on the low speed schedule and
* need to find something that matches on the high speed one.
* @index: The index into qh->hs_transfers that we're working with.
*
* Returns: 0 for success or an error code. Upon success the
* dwc2_hs_transfer_time specified by "index" will be updated.
*/
static int dwc2_hs_pmap_schedule(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
bool only_one_period, int index)
{
struct dwc2_hs_transfer_time *trans_time = qh->hs_transfers + index;
int us;
us = pmap_schedule(hsotg->hs_periodic_bitmap,
DWC2_HS_PERIODIC_US_PER_UFRAME,
DWC2_HS_SCHEDULE_UFRAMES, trans_time->duration_us,
qh->host_interval, trans_time->start_schedule_us,
only_one_period);
if (us < 0)
return us;
trans_time->start_schedule_us = us;
return 0;
}
/**
* dwc2_ls_pmap_unschedule() - Undo work done by dwc2_hs_pmap_schedule()
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
*/
static void dwc2_hs_pmap_unschedule(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh, int index)
{
struct dwc2_hs_transfer_time *trans_time = qh->hs_transfers + index;
pmap_unschedule(hsotg->hs_periodic_bitmap,
DWC2_HS_PERIODIC_US_PER_UFRAME,
DWC2_HS_SCHEDULE_UFRAMES, trans_time->duration_us,
qh->host_interval, trans_time->start_schedule_us);
}
/**
* dwc2_uframe_schedule_split - Schedule a QH for a periodic split xfer.
*
* This is the most complicated thing in USB. We have to find matching time
* in both the global high speed schedule for the port and the low speed
* schedule for the TT associated with the given device.
*
* Being here means that the host must be running in high speed mode and the
* device is in low or full speed mode (and behind a hub).
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
*/
static int dwc2_uframe_schedule_split(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh)
{
int bytecount = dwc2_hb_mult(qh->maxp) * dwc2_max_packet(qh->maxp);
int ls_search_slice;
int err = 0;
int host_interval_in_sched;
/*
* The interval (how often to repeat) in the actual host schedule.
* See pmap_schedule() for gcd() explanation.
*/
host_interval_in_sched = gcd(qh->host_interval,
DWC2_HS_SCHEDULE_UFRAMES);
/*
* We always try to find space in the low speed schedule first, then
* try to find high speed time that matches. If we don't, we'll bump
* up the place we start searching in the low speed schedule and try
* again. To start we'll look right at the beginning of the low speed
* schedule.
*
* Note that this will tend to front-load the high speed schedule.
* We may eventually want to try to avoid this by either considering
* both schedules together or doing some sort of round robin.
*/
ls_search_slice = 0;
while (ls_search_slice < DWC2_LS_SCHEDULE_SLICES) {
int start_s_uframe;
int ssplit_s_uframe;
int second_s_uframe;
int rel_uframe;
int first_count;
int middle_count;
int end_count;
int first_data_bytes;
int other_data_bytes;
int i;
if (qh->schedule_low_speed) {
err = dwc2_ls_pmap_schedule(hsotg, qh, ls_search_slice);
/*
* If we got an error here there's no other magic we
* can do, so bail. All the looping above is only
* helpful to redo things if we got a low speed slot
* and then couldn't find a matching high speed slot.
*/
if (err)
return err;
} else {
/* Must be missing the tt structure? Why? */
WARN_ON_ONCE(1);
}
/*
* This will give us a number 0 - 7 if
* DWC2_LS_SCHEDULE_FRAMES == 1, or 0 - 15 if == 2, or ...
*/
start_s_uframe = qh->ls_start_schedule_slice /
DWC2_SLICES_PER_UFRAME;
/* Get a number that's always 0 - 7 */
rel_uframe = (start_s_uframe % 8);
/*
* If we were going to start in uframe 7 then we would need to
* issue a start split in uframe 6, which spec says is not OK.
* Move on to the next full frame (assuming there is one).
*
* See 11.18.4 Host Split Transaction Scheduling Requirements
* bullet 1.
*/
if (rel_uframe == 7) {
if (qh->schedule_low_speed)
dwc2_ls_pmap_unschedule(hsotg, qh);
ls_search_slice =
(qh->ls_start_schedule_slice /
DWC2_LS_PERIODIC_SLICES_PER_FRAME + 1) *
DWC2_LS_PERIODIC_SLICES_PER_FRAME;
continue;
}
/*
* For ISOC in:
* - start split (frame -1)
* - complete split w/ data (frame +1)
* - complete split w/ data (frame +2)
* - ...
* - complete split w/ data (frame +num_data_packets)
* - complete split w/ data (frame +num_data_packets+1)
* - complete split w/ data (frame +num_data_packets+2, max 8)
* ...though if frame was "0" then max is 7...
*
* For ISOC out we might need to do:
* - start split w/ data (frame -1)
* - start split w/ data (frame +0)
* - ...
* - start split w/ data (frame +num_data_packets-2)
*
* For INTERRUPT in we might need to do:
* - start split (frame -1)
* - complete split w/ data (frame +1)
* - complete split w/ data (frame +2)
* - complete split w/ data (frame +3, max 8)
*
* For INTERRUPT out we might need to do:
* - start split w/ data (frame -1)
* - complete split (frame +1)
* - complete split (frame +2)
* - complete split (frame +3, max 8)
*
* Start adjusting!
*/
ssplit_s_uframe = (start_s_uframe +
host_interval_in_sched - 1) %
host_interval_in_sched;
if (qh->ep_type == USB_ENDPOINT_XFER_ISOC && !qh->ep_is_in)
second_s_uframe = start_s_uframe;
else
second_s_uframe = start_s_uframe + 1;
/* First data transfer might not be all 188 bytes. */
first_data_bytes = 188 -
DIV_ROUND_UP(188 * (qh->ls_start_schedule_slice %
DWC2_SLICES_PER_UFRAME),
DWC2_SLICES_PER_UFRAME);
if (first_data_bytes > bytecount)
first_data_bytes = bytecount;
other_data_bytes = bytecount - first_data_bytes;
/*
* For now, skip OUT xfers where first xfer is partial
*
* Main dwc2 code assumes:
* - INT transfers never get split in two.
* - ISOC transfers can always transfer 188 bytes the first
* time.
*
* Until that code is fixed, try again if the first transfer
* couldn't transfer everything.
*
* This code can be removed if/when the rest of dwc2 handles
* the above cases. Until it's fixed we just won't be able
* to schedule quite as tightly.
*/
if (!qh->ep_is_in &&
(first_data_bytes != min_t(int, 188, bytecount))) {
dwc2_sch_dbg(hsotg,
"QH=%p avoiding broken 1st xfer (%d, %d)\n",
qh, first_data_bytes, bytecount);
if (qh->schedule_low_speed)
dwc2_ls_pmap_unschedule(hsotg, qh);
ls_search_slice = (start_s_uframe + 1) *
DWC2_SLICES_PER_UFRAME;
continue;
}
/* Start by assuming transfers for the bytes */
qh->num_hs_transfers = 1 + DIV_ROUND_UP(other_data_bytes, 188);
/*
* Everything except ISOC OUT has extra transfers. Rules are
* complicated. See 11.18.4 Host Split Transaction Scheduling
* Requirements bullet 3.
*/
if (qh->ep_type == USB_ENDPOINT_XFER_INT) {
if (rel_uframe == 6)
qh->num_hs_transfers += 2;
else
qh->num_hs_transfers += 3;
if (qh->ep_is_in) {
/*
* First is start split, middle/end is data.
* Allocate full data bytes for all data.
*/
first_count = 4;
middle_count = bytecount;
end_count = bytecount;
} else {
/*
* First is data, middle/end is complete.
* First transfer and second can have data.
* Rest should just have complete split.
*/
first_count = first_data_bytes;
middle_count = max_t(int, 4, other_data_bytes);
end_count = 4;
}
} else {
if (qh->ep_is_in) {
int last;
/* Account for the start split */
qh->num_hs_transfers++;
/* Calculate "L" value from spec */
last = rel_uframe + qh->num_hs_transfers + 1;
/* Start with basic case */
if (last <= 6)
qh->num_hs_transfers += 2;
else
qh->num_hs_transfers += 1;
/* Adjust downwards */
if (last >= 6 && rel_uframe == 0)
qh->num_hs_transfers--;
/* 1st = start; rest can contain data */
first_count = 4;
middle_count = min_t(int, 188, bytecount);
end_count = middle_count;
} else {
/* All contain data, last might be smaller */
first_count = first_data_bytes;
middle_count = min_t(int, 188,
other_data_bytes);
end_count = other_data_bytes % 188;
}
}
/* Assign durations per uFrame */
qh->hs_transfers[0].duration_us = HS_USECS_ISO(first_count);
for (i = 1; i < qh->num_hs_transfers - 1; i++)
qh->hs_transfers[i].duration_us =
HS_USECS_ISO(middle_count);
if (qh->num_hs_transfers > 1)
qh->hs_transfers[qh->num_hs_transfers - 1].duration_us =
HS_USECS_ISO(end_count);
/*
* Assign start us. The call below to dwc2_hs_pmap_schedule()
* will start with these numbers but may adjust within the same
* microframe.
*/
qh->hs_transfers[0].start_schedule_us =
ssplit_s_uframe * DWC2_HS_PERIODIC_US_PER_UFRAME;
for (i = 1; i < qh->num_hs_transfers; i++)
qh->hs_transfers[i].start_schedule_us =
((second_s_uframe + i - 1) %
DWC2_HS_SCHEDULE_UFRAMES) *
DWC2_HS_PERIODIC_US_PER_UFRAME;
/* Try to schedule with filled in hs_transfers above */
for (i = 0; i < qh->num_hs_transfers; i++) {
err = dwc2_hs_pmap_schedule(hsotg, qh, true, i);
if (err)
break;
}
/* If we scheduled all w/out breaking out then we're all good */
if (i == qh->num_hs_transfers)
break;
for (; i >= 0; i--)
dwc2_hs_pmap_unschedule(hsotg, qh, i);
if (qh->schedule_low_speed)
dwc2_ls_pmap_unschedule(hsotg, qh);
/* Try again starting in the next microframe */
ls_search_slice = (start_s_uframe + 1) * DWC2_SLICES_PER_UFRAME;
}
if (ls_search_slice >= DWC2_LS_SCHEDULE_SLICES)
return -ENOSPC;
return 0;
}
/**
* dwc2_uframe_schedule_hs - Schedule a QH for a periodic high speed xfer.
*
* Basically this just wraps dwc2_hs_pmap_schedule() to provide a clean
* interface.
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
*/
static int dwc2_uframe_schedule_hs(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
/* In non-split host and device time are the same */
WARN_ON(qh->host_us != qh->device_us);
WARN_ON(qh->host_interval != qh->device_interval);
WARN_ON(qh->num_hs_transfers != 1);
/* We'll have one transfer; init start to 0 before calling scheduler */
qh->hs_transfers[0].start_schedule_us = 0;
qh->hs_transfers[0].duration_us = qh->host_us;
return dwc2_hs_pmap_schedule(hsotg, qh, false, 0);
}
/**
* dwc2_uframe_schedule_ls - Schedule a QH for a periodic low/full speed xfer.
*
* Basically this just wraps dwc2_ls_pmap_schedule() to provide a clean
* interface.
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
*/
static int dwc2_uframe_schedule_ls(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
/* In non-split host and device time are the same */
WARN_ON(qh->host_us != qh->device_us);
WARN_ON(qh->host_interval != qh->device_interval);
WARN_ON(!qh->schedule_low_speed);
/* Run on the main low speed schedule (no split = no hub = no TT) */
return dwc2_ls_pmap_schedule(hsotg, qh, 0);
}
/**
* dwc2_uframe_schedule - Schedule a QH for a periodic xfer.
*
* Calls one of the 3 sub-function depending on what type of transfer this QH
* is for. Also adds some printing.
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
*/
static int dwc2_uframe_schedule(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
int ret;
if (qh->dev_speed == USB_SPEED_HIGH)
ret = dwc2_uframe_schedule_hs(hsotg, qh);
else if (!qh->do_split)
ret = dwc2_uframe_schedule_ls(hsotg, qh);
else
ret = dwc2_uframe_schedule_split(hsotg, qh);
if (ret)
dwc2_sch_dbg(hsotg, "QH=%p Failed to schedule %d\n", qh, ret);
else
dwc2_qh_schedule_print(hsotg, qh);
return ret;
}
/**
* dwc2_uframe_unschedule - Undoes dwc2_uframe_schedule().
*
* @hsotg: The HCD state structure for the DWC OTG controller.
* @qh: QH for the periodic transfer.
*/
static void dwc2_uframe_unschedule(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
int i;
for (i = 0; i < qh->num_hs_transfers; i++)
dwc2_hs_pmap_unschedule(hsotg, qh, i);
if (qh->schedule_low_speed)
dwc2_ls_pmap_unschedule(hsotg, qh);
dwc2_sch_dbg(hsotg, "QH=%p Unscheduled\n", qh);
}
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/**
* dwc2_pick_first_frame() - Choose 1st frame for qh that's already scheduled
*
* Takes a qh that has already been scheduled (which means we know we have the
* bandwdith reserved for us) and set the next_active_frame and the
* start_active_frame.
*
* This is expected to be called on qh's that weren't previously actively
* running. It just picks the next frame that we can fit into without any
* thought about the past.
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: QH for a periodic endpoint
*
*/
static void dwc2_pick_first_frame(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
u16 frame_number;
u16 earliest_frame;
u16 next_active_frame;
u16 relative_frame;
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
u16 interval;
/*
* Use the real frame number rather than the cached value as of the
* last SOF to give us a little extra slop.
*/
frame_number = dwc2_hcd_get_frame_number(hsotg);
/*
* We wouldn't want to start any earlier than the next frame just in
* case the frame number ticks as we're doing this calculation.
*
* NOTE: if we could quantify how long till we actually get scheduled
* we might be able to avoid the "+ 1" by looking at the upper part of
* HFNUM (the FRREM field). For now we'll just use the + 1 though.
*/
earliest_frame = dwc2_frame_num_inc(frame_number, 1);
next_active_frame = earliest_frame;
/* Get the "no microframe schduler" out of the way... */
if (!hsotg->params.uframe_sched) {
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
if (qh->do_split)
/* Splits are active at microframe 0 minus 1 */
next_active_frame |= 0x7;
goto exit;
}
if (qh->dev_speed == USB_SPEED_HIGH || qh->do_split) {
/*
* We're either at high speed or we're doing a split (which
* means we're talking high speed to a hub). In any case
* the first frame should be based on when the first scheduled
* event is.
*/
WARN_ON(qh->num_hs_transfers < 1);
relative_frame = qh->hs_transfers[0].start_schedule_us /
DWC2_HS_PERIODIC_US_PER_UFRAME;
/* Adjust interval as per high speed schedule */
interval = gcd(qh->host_interval, DWC2_HS_SCHEDULE_UFRAMES);
} else {
/*
* Low or full speed directly on dwc2. Just about the same
* as high speed but on a different schedule and with slightly
* different adjustments. Note that this works because when
* the host and device are both low speed then frames in the
* controller tick at low speed.
*/
relative_frame = qh->ls_start_schedule_slice /
DWC2_LS_PERIODIC_SLICES_PER_FRAME;
interval = gcd(qh->host_interval, DWC2_LS_SCHEDULE_FRAMES);
}
/* Scheduler messed up if frame is past interval */
WARN_ON(relative_frame >= interval);
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/*
* We know interval must divide (HFNUM_MAX_FRNUM + 1) now that we've
* done the gcd(), so it's safe to move to the beginning of the current
* interval like this.
*
* After this we might be before earliest_frame, but don't worry,
* we'll fix it...
*/
next_active_frame = (next_active_frame / interval) * interval;
/*
* Actually choose to start at the frame number we've been
* scheduled for.
*/
next_active_frame = dwc2_frame_num_inc(next_active_frame,
relative_frame);
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/*
* We actually need 1 frame before since the next_active_frame is
* the frame number we'll be put on the ready list and we won't be on
* the bus until 1 frame later.
*/
next_active_frame = dwc2_frame_num_dec(next_active_frame, 1);
/*
* By now we might actually be before the earliest_frame. Let's move
* up intervals until we're not.
*/
while (dwc2_frame_num_gt(earliest_frame, next_active_frame))
next_active_frame = dwc2_frame_num_inc(next_active_frame,
interval);
exit:
qh->next_active_frame = next_active_frame;
qh->start_active_frame = next_active_frame;
dwc2_sch_vdbg(hsotg, "QH=%p First fn=%04x nxt=%04x\n",
qh, frame_number, qh->next_active_frame);
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
}
/**
* dwc2_do_reserve() - Make a periodic reservation
*
* Try to allocate space in the periodic schedule. Depending on parameters
* this might use the microframe scheduler or the dumb scheduler.
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: QH for the periodic transfer.
*
* Returns: 0 upon success; error upon failure.
*/
static int dwc2_do_reserve(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
int status;
if (hsotg->params.uframe_sched) {
status = dwc2_uframe_schedule(hsotg, qh);
} else {
status = dwc2_periodic_channel_available(hsotg);
if (status) {
dev_info(hsotg->dev,
"%s: No host channel available for periodic transfer\n",
__func__);
return status;
}
status = dwc2_check_periodic_bandwidth(hsotg, qh);
}
if (status) {
dev_dbg(hsotg->dev,
"%s: Insufficient periodic bandwidth for periodic transfer\n",
__func__);
return status;
}
if (!hsotg->params.uframe_sched)
/* Reserve periodic channel */
hsotg->periodic_channels++;
/* Update claimed usecs per (micro)frame */
hsotg->periodic_usecs += qh->host_us;
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
dwc2_pick_first_frame(hsotg, qh);
return 0;
}
/**
* dwc2_do_unreserve() - Actually release the periodic reservation
*
* This function actually releases the periodic bandwidth that was reserved
* by the given qh.
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: QH for the periodic transfer.
*/
static void dwc2_do_unreserve(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
assert_spin_locked(&hsotg->lock);
WARN_ON(!qh->unreserve_pending);
/* No more unreserve pending--we're doing it */
qh->unreserve_pending = false;
if (WARN_ON(!list_empty(&qh->qh_list_entry)))
list_del_init(&qh->qh_list_entry);
/* Update claimed usecs per (micro)frame */
hsotg->periodic_usecs -= qh->host_us;
if (hsotg->params.uframe_sched) {
dwc2_uframe_unschedule(hsotg, qh);
} else {
/* Release periodic channel reservation */
hsotg->periodic_channels--;
}
}
/**
* dwc2_unreserve_timer_fn() - Timer function to release periodic reservation
*
* According to the kernel doc for usb_submit_urb() (specifically the part about
* "Reserved Bandwidth Transfers"), we need to keep a reservation active as
* long as a device driver keeps submitting. Since we're using HCD_BH to give
* back the URB we need to give the driver a little bit of time before we
* release the reservation. This worker is called after the appropriate
* delay.
*
* @work: Pointer to a qh unreserve_work.
*/
treewide: setup_timer() -> timer_setup() This converts all remaining cases of the old setup_timer() API into using timer_setup(), where the callback argument is the structure already holding the struct timer_list. These should have no behavioral changes, since they just change which pointer is passed into the callback with the same available pointers after conversion. It handles the following examples, in addition to some other variations. Casting from unsigned long: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... setup_timer(&ptr->my_timer, my_callback, ptr); and forced object casts: void my_callback(struct something *ptr) { ... } ... setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr); become: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... timer_setup(&ptr->my_timer, my_callback, 0); Direct function assignments: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... ptr->my_timer.function = my_callback; have a temporary cast added, along with converting the args: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback; And finally, callbacks without a data assignment: void my_callback(unsigned long data) { ... } ... setup_timer(&ptr->my_timer, my_callback, 0); have their argument renamed to verify they're unused during conversion: void my_callback(struct timer_list *unused) { ... } ... timer_setup(&ptr->my_timer, my_callback, 0); The conversion is done with the following Coccinelle script: spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/timer_setup.cocci @fix_address_of@ expression e; @@ setup_timer( -&(e) +&e , ...) // Update any raw setup_timer() usages that have a NULL callback, but // would otherwise match change_timer_function_usage, since the latter // will update all function assignments done in the face of a NULL // function initialization in setup_timer(). @change_timer_function_usage_NULL@ expression _E; identifier _timer; type _cast_data; @@ ( -setup_timer(&_E->_timer, NULL, _E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E->_timer, NULL, (_cast_data)_E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E._timer, NULL, &_E); +timer_setup(&_E._timer, NULL, 0); | -setup_timer(&_E._timer, NULL, (_cast_data)&_E); +timer_setup(&_E._timer, NULL, 0); ) @change_timer_function_usage@ expression _E; identifier _timer; struct timer_list _stl; identifier _callback; type _cast_func, _cast_data; @@ ( -setup_timer(&_E->_timer, _callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | _E->_timer@_stl.function = _callback; | _E->_timer@_stl.function = &_callback; | _E->_timer@_stl.function = (_cast_func)_callback; | _E->_timer@_stl.function = (_cast_func)&_callback; | _E._timer@_stl.function = _callback; | _E._timer@_stl.function = &_callback; | _E._timer@_stl.function = (_cast_func)_callback; | _E._timer@_stl.function = (_cast_func)&_callback; ) // callback(unsigned long arg) @change_callback_handle_cast depends on change_timer_function_usage@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; identifier _handle; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { ( ... when != _origarg _handletype *_handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg ) } // callback(unsigned long arg) without existing variable @change_callback_handle_cast_no_arg depends on change_timer_function_usage && !change_callback_handle_cast@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { + _handletype *_origarg = from_timer(_origarg, t, _timer); + ... when != _origarg - (_handletype *)_origarg + _origarg ... when != _origarg } // Avoid already converted callbacks. @match_callback_converted depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier t; @@ void _callback(struct timer_list *t) { ... } // callback(struct something *handle) @change_callback_handle_arg depends on change_timer_function_usage && !match_callback_converted && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; @@ void _callback( -_handletype *_handle +struct timer_list *t ) { + _handletype *_handle = from_timer(_handle, t, _timer); ... } // If change_callback_handle_arg ran on an empty function, remove // the added handler. @unchange_callback_handle_arg depends on change_timer_function_usage && change_callback_handle_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; identifier t; @@ void _callback(struct timer_list *t) { - _handletype *_handle = from_timer(_handle, t, _timer); } // We only want to refactor the setup_timer() data argument if we've found // the matching callback. This undoes changes in change_timer_function_usage. @unchange_timer_function_usage depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg && !change_callback_handle_arg@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type change_timer_function_usage._cast_data; @@ ( -timer_setup(&_E->_timer, _callback, 0); +setup_timer(&_E->_timer, _callback, (_cast_data)_E); | -timer_setup(&_E._timer, _callback, 0); +setup_timer(&_E._timer, _callback, (_cast_data)&_E); ) // If we fixed a callback from a .function assignment, fix the // assignment cast now. @change_timer_function_assignment depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_func; typedef TIMER_FUNC_TYPE; @@ ( _E->_timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -&_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)_callback; +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -&_callback; +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; ) // Sometimes timer functions are called directly. Replace matched args. @change_timer_function_calls depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression _E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_data; @@ _callback( ( -(_cast_data)_E +&_E->_timer | -(_cast_data)&_E +&_E._timer | -_E +&_E->_timer ) ) // If a timer has been configured without a data argument, it can be // converted without regard to the callback argument, since it is unused. @match_timer_function_unused_data@ expression _E; identifier _timer; identifier _callback; @@ ( -setup_timer(&_E->_timer, _callback, 0); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0L); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0UL); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0L); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0UL); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_timer, _callback, 0); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0L); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0UL); +timer_setup(&_timer, _callback, 0); | -setup_timer(_timer, _callback, 0); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0L); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0UL); +timer_setup(_timer, _callback, 0); ) @change_callback_unused_data depends on match_timer_function_unused_data@ identifier match_timer_function_unused_data._callback; type _origtype; identifier _origarg; @@ void _callback( -_origtype _origarg +struct timer_list *unused ) { ... when != _origarg } Signed-off-by: Kees Cook <keescook@chromium.org>
2017-10-17 04:43:17 +07:00
static void dwc2_unreserve_timer_fn(struct timer_list *t)
{
treewide: setup_timer() -> timer_setup() This converts all remaining cases of the old setup_timer() API into using timer_setup(), where the callback argument is the structure already holding the struct timer_list. These should have no behavioral changes, since they just change which pointer is passed into the callback with the same available pointers after conversion. It handles the following examples, in addition to some other variations. Casting from unsigned long: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... setup_timer(&ptr->my_timer, my_callback, ptr); and forced object casts: void my_callback(struct something *ptr) { ... } ... setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr); become: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... timer_setup(&ptr->my_timer, my_callback, 0); Direct function assignments: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... ptr->my_timer.function = my_callback; have a temporary cast added, along with converting the args: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback; And finally, callbacks without a data assignment: void my_callback(unsigned long data) { ... } ... setup_timer(&ptr->my_timer, my_callback, 0); have their argument renamed to verify they're unused during conversion: void my_callback(struct timer_list *unused) { ... } ... timer_setup(&ptr->my_timer, my_callback, 0); The conversion is done with the following Coccinelle script: spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/timer_setup.cocci @fix_address_of@ expression e; @@ setup_timer( -&(e) +&e , ...) // Update any raw setup_timer() usages that have a NULL callback, but // would otherwise match change_timer_function_usage, since the latter // will update all function assignments done in the face of a NULL // function initialization in setup_timer(). @change_timer_function_usage_NULL@ expression _E; identifier _timer; type _cast_data; @@ ( -setup_timer(&_E->_timer, NULL, _E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E->_timer, NULL, (_cast_data)_E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E._timer, NULL, &_E); +timer_setup(&_E._timer, NULL, 0); | -setup_timer(&_E._timer, NULL, (_cast_data)&_E); +timer_setup(&_E._timer, NULL, 0); ) @change_timer_function_usage@ expression _E; identifier _timer; struct timer_list _stl; identifier _callback; type _cast_func, _cast_data; @@ ( -setup_timer(&_E->_timer, _callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | _E->_timer@_stl.function = _callback; | _E->_timer@_stl.function = &_callback; | _E->_timer@_stl.function = (_cast_func)_callback; | _E->_timer@_stl.function = (_cast_func)&_callback; | _E._timer@_stl.function = _callback; | _E._timer@_stl.function = &_callback; | _E._timer@_stl.function = (_cast_func)_callback; | _E._timer@_stl.function = (_cast_func)&_callback; ) // callback(unsigned long arg) @change_callback_handle_cast depends on change_timer_function_usage@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; identifier _handle; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { ( ... when != _origarg _handletype *_handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg ) } // callback(unsigned long arg) without existing variable @change_callback_handle_cast_no_arg depends on change_timer_function_usage && !change_callback_handle_cast@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { + _handletype *_origarg = from_timer(_origarg, t, _timer); + ... when != _origarg - (_handletype *)_origarg + _origarg ... when != _origarg } // Avoid already converted callbacks. @match_callback_converted depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier t; @@ void _callback(struct timer_list *t) { ... } // callback(struct something *handle) @change_callback_handle_arg depends on change_timer_function_usage && !match_callback_converted && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; @@ void _callback( -_handletype *_handle +struct timer_list *t ) { + _handletype *_handle = from_timer(_handle, t, _timer); ... } // If change_callback_handle_arg ran on an empty function, remove // the added handler. @unchange_callback_handle_arg depends on change_timer_function_usage && change_callback_handle_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; identifier t; @@ void _callback(struct timer_list *t) { - _handletype *_handle = from_timer(_handle, t, _timer); } // We only want to refactor the setup_timer() data argument if we've found // the matching callback. This undoes changes in change_timer_function_usage. @unchange_timer_function_usage depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg && !change_callback_handle_arg@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type change_timer_function_usage._cast_data; @@ ( -timer_setup(&_E->_timer, _callback, 0); +setup_timer(&_E->_timer, _callback, (_cast_data)_E); | -timer_setup(&_E._timer, _callback, 0); +setup_timer(&_E._timer, _callback, (_cast_data)&_E); ) // If we fixed a callback from a .function assignment, fix the // assignment cast now. @change_timer_function_assignment depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_func; typedef TIMER_FUNC_TYPE; @@ ( _E->_timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -&_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)_callback; +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -&_callback; +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; ) // Sometimes timer functions are called directly. Replace matched args. @change_timer_function_calls depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression _E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_data; @@ _callback( ( -(_cast_data)_E +&_E->_timer | -(_cast_data)&_E +&_E._timer | -_E +&_E->_timer ) ) // If a timer has been configured without a data argument, it can be // converted without regard to the callback argument, since it is unused. @match_timer_function_unused_data@ expression _E; identifier _timer; identifier _callback; @@ ( -setup_timer(&_E->_timer, _callback, 0); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0L); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0UL); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0L); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0UL); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_timer, _callback, 0); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0L); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0UL); +timer_setup(&_timer, _callback, 0); | -setup_timer(_timer, _callback, 0); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0L); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0UL); +timer_setup(_timer, _callback, 0); ) @change_callback_unused_data depends on match_timer_function_unused_data@ identifier match_timer_function_unused_data._callback; type _origtype; identifier _origarg; @@ void _callback( -_origtype _origarg +struct timer_list *unused ) { ... when != _origarg } Signed-off-by: Kees Cook <keescook@chromium.org>
2017-10-17 04:43:17 +07:00
struct dwc2_qh *qh = from_timer(qh, t, unreserve_timer);
struct dwc2_hsotg *hsotg = qh->hsotg;
unsigned long flags;
/*
* Wait for the lock, or for us to be scheduled again. We
* could be scheduled again if:
* - We started executing but didn't get the lock yet.
* - A new reservation came in, but cancel didn't take effect
* because we already started executing.
* - The timer has been kicked again.
* In that case cancel and wait for the next call.
*/
while (!spin_trylock_irqsave(&hsotg->lock, flags)) {
if (timer_pending(&qh->unreserve_timer))
return;
}
/*
* Might be no more unreserve pending if:
* - We started executing but didn't get the lock yet.
* - A new reservation came in, but cancel didn't take effect
* because we already started executing.
*
* We can't put this in the loop above because unreserve_pending needs
* to be accessed under lock, so we can only check it once we got the
* lock.
*/
if (qh->unreserve_pending)
dwc2_do_unreserve(hsotg, qh);
spin_unlock_irqrestore(&hsotg->lock, flags);
}
/**
* dwc2_check_max_xfer_size() - Checks that the max transfer size allowed in a
* host channel is large enough to handle the maximum data transfer in a single
* (micro)frame for a periodic transfer
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: QH for a periodic endpoint
*
* Return: 0 if successful, negative error code otherwise
*/
static int dwc2_check_max_xfer_size(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh)
{
u32 max_xfer_size;
u32 max_channel_xfer_size;
int status = 0;
max_xfer_size = dwc2_max_packet(qh->maxp) * dwc2_hb_mult(qh->maxp);
max_channel_xfer_size = hsotg->params.max_transfer_size;
if (max_xfer_size > max_channel_xfer_size) {
dev_err(hsotg->dev,
"%s: Periodic xfer length %d > max xfer length for channel %d\n",
__func__, max_xfer_size, max_channel_xfer_size);
status = -ENOSPC;
}
return status;
}
/**
* dwc2_schedule_periodic() - Schedules an interrupt or isochronous transfer in
* the periodic schedule
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: QH for the periodic transfer. The QH should already contain the
* scheduling information.
*
* Return: 0 if successful, negative error code otherwise
*/
static int dwc2_schedule_periodic(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
int status;
status = dwc2_check_max_xfer_size(hsotg, qh);
if (status) {
dev_dbg(hsotg->dev,
"%s: Channel max transfer size too small for periodic transfer\n",
__func__);
return status;
}
/* Cancel pending unreserve; if canceled OK, unreserve was pending */
if (del_timer(&qh->unreserve_timer))
WARN_ON(!qh->unreserve_pending);
/*
* Only need to reserve if there's not an unreserve pending, since if an
* unreserve is pending then by definition our old reservation is still
* valid. Unreserve might still be pending even if we didn't cancel if
* dwc2_unreserve_timer_fn() already started. Code in the timer handles
* that case.
*/
if (!qh->unreserve_pending) {
status = dwc2_do_reserve(hsotg, qh);
if (status)
return status;
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
} else {
/*
* It might have been a while, so make sure that frame_number
* is still good. Note: we could also try to use the similar
* dwc2_next_periodic_start() but that schedules much more
* tightly and we might need to hurry and queue things up.
*/
if (dwc2_frame_num_le(qh->next_active_frame,
hsotg->frame_number))
dwc2_pick_first_frame(hsotg, qh);
}
qh->unreserve_pending = 0;
if (hsotg->params.dma_desc_enable)
/* Don't rely on SOF and start in ready schedule */
list_add_tail(&qh->qh_list_entry, &hsotg->periodic_sched_ready);
else
/* Always start in inactive schedule */
list_add_tail(&qh->qh_list_entry,
&hsotg->periodic_sched_inactive);
return 0;
}
/**
* dwc2_deschedule_periodic() - Removes an interrupt or isochronous transfer
* from the periodic schedule
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: QH for the periodic transfer
*/
static void dwc2_deschedule_periodic(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh)
{
bool did_modify;
assert_spin_locked(&hsotg->lock);
/*
* Schedule the unreserve to happen in a little bit. Cases here:
* - Unreserve worker might be sitting there waiting to grab the lock.
* In this case it will notice it's been schedule again and will
* quit.
* - Unreserve worker might not be scheduled.
*
* We should never already be scheduled since dwc2_schedule_periodic()
* should have canceled the scheduled unreserve timer (hence the
* warning on did_modify).
*
* We add + 1 to the timer to guarantee that at least 1 jiffy has
* passed (otherwise if the jiffy counter might tick right after we
* read it and we'll get no delay).
*/
did_modify = mod_timer(&qh->unreserve_timer,
jiffies + DWC2_UNRESERVE_DELAY + 1);
WARN_ON(did_modify);
qh->unreserve_pending = 1;
list_del_init(&qh->qh_list_entry);
}
/**
* dwc2_qh_init() - Initializes a QH structure
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: The QH to init
* @urb: Holds the information about the device/endpoint needed to initialize
* the QH
* @mem_flags: Flags for allocating memory.
*/
static void dwc2_qh_init(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
struct dwc2_hcd_urb *urb, gfp_t mem_flags)
{
int dev_speed = dwc2_host_get_speed(hsotg, urb->priv);
u8 ep_type = dwc2_hcd_get_pipe_type(&urb->pipe_info);
bool ep_is_in = !!dwc2_hcd_is_pipe_in(&urb->pipe_info);
bool ep_is_isoc = (ep_type == USB_ENDPOINT_XFER_ISOC);
bool ep_is_int = (ep_type == USB_ENDPOINT_XFER_INT);
u32 hprt = dwc2_readl(hsotg->regs + HPRT0);
u32 prtspd = (hprt & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT;
bool do_split = (prtspd == HPRT0_SPD_HIGH_SPEED &&
dev_speed != USB_SPEED_HIGH);
int maxp = dwc2_hcd_get_mps(&urb->pipe_info);
int bytecount = dwc2_hb_mult(maxp) * dwc2_max_packet(maxp);
char *speed, *type;
/* Initialize QH */
qh->hsotg = hsotg;
treewide: setup_timer() -> timer_setup() This converts all remaining cases of the old setup_timer() API into using timer_setup(), where the callback argument is the structure already holding the struct timer_list. These should have no behavioral changes, since they just change which pointer is passed into the callback with the same available pointers after conversion. It handles the following examples, in addition to some other variations. Casting from unsigned long: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... setup_timer(&ptr->my_timer, my_callback, ptr); and forced object casts: void my_callback(struct something *ptr) { ... } ... setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr); become: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... timer_setup(&ptr->my_timer, my_callback, 0); Direct function assignments: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... ptr->my_timer.function = my_callback; have a temporary cast added, along with converting the args: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback; And finally, callbacks without a data assignment: void my_callback(unsigned long data) { ... } ... setup_timer(&ptr->my_timer, my_callback, 0); have their argument renamed to verify they're unused during conversion: void my_callback(struct timer_list *unused) { ... } ... timer_setup(&ptr->my_timer, my_callback, 0); The conversion is done with the following Coccinelle script: spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/timer_setup.cocci @fix_address_of@ expression e; @@ setup_timer( -&(e) +&e , ...) // Update any raw setup_timer() usages that have a NULL callback, but // would otherwise match change_timer_function_usage, since the latter // will update all function assignments done in the face of a NULL // function initialization in setup_timer(). @change_timer_function_usage_NULL@ expression _E; identifier _timer; type _cast_data; @@ ( -setup_timer(&_E->_timer, NULL, _E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E->_timer, NULL, (_cast_data)_E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E._timer, NULL, &_E); +timer_setup(&_E._timer, NULL, 0); | -setup_timer(&_E._timer, NULL, (_cast_data)&_E); +timer_setup(&_E._timer, NULL, 0); ) @change_timer_function_usage@ expression _E; identifier _timer; struct timer_list _stl; identifier _callback; type _cast_func, _cast_data; @@ ( -setup_timer(&_E->_timer, _callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | _E->_timer@_stl.function = _callback; | _E->_timer@_stl.function = &_callback; | _E->_timer@_stl.function = (_cast_func)_callback; | _E->_timer@_stl.function = (_cast_func)&_callback; | _E._timer@_stl.function = _callback; | _E._timer@_stl.function = &_callback; | _E._timer@_stl.function = (_cast_func)_callback; | _E._timer@_stl.function = (_cast_func)&_callback; ) // callback(unsigned long arg) @change_callback_handle_cast depends on change_timer_function_usage@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; identifier _handle; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { ( ... when != _origarg _handletype *_handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg ) } // callback(unsigned long arg) without existing variable @change_callback_handle_cast_no_arg depends on change_timer_function_usage && !change_callback_handle_cast@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { + _handletype *_origarg = from_timer(_origarg, t, _timer); + ... when != _origarg - (_handletype *)_origarg + _origarg ... when != _origarg } // Avoid already converted callbacks. @match_callback_converted depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier t; @@ void _callback(struct timer_list *t) { ... } // callback(struct something *handle) @change_callback_handle_arg depends on change_timer_function_usage && !match_callback_converted && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; @@ void _callback( -_handletype *_handle +struct timer_list *t ) { + _handletype *_handle = from_timer(_handle, t, _timer); ... } // If change_callback_handle_arg ran on an empty function, remove // the added handler. @unchange_callback_handle_arg depends on change_timer_function_usage && change_callback_handle_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; identifier t; @@ void _callback(struct timer_list *t) { - _handletype *_handle = from_timer(_handle, t, _timer); } // We only want to refactor the setup_timer() data argument if we've found // the matching callback. This undoes changes in change_timer_function_usage. @unchange_timer_function_usage depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg && !change_callback_handle_arg@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type change_timer_function_usage._cast_data; @@ ( -timer_setup(&_E->_timer, _callback, 0); +setup_timer(&_E->_timer, _callback, (_cast_data)_E); | -timer_setup(&_E._timer, _callback, 0); +setup_timer(&_E._timer, _callback, (_cast_data)&_E); ) // If we fixed a callback from a .function assignment, fix the // assignment cast now. @change_timer_function_assignment depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_func; typedef TIMER_FUNC_TYPE; @@ ( _E->_timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -&_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)_callback; +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -&_callback; +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; ) // Sometimes timer functions are called directly. Replace matched args. @change_timer_function_calls depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression _E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_data; @@ _callback( ( -(_cast_data)_E +&_E->_timer | -(_cast_data)&_E +&_E._timer | -_E +&_E->_timer ) ) // If a timer has been configured without a data argument, it can be // converted without regard to the callback argument, since it is unused. @match_timer_function_unused_data@ expression _E; identifier _timer; identifier _callback; @@ ( -setup_timer(&_E->_timer, _callback, 0); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0L); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0UL); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0L); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0UL); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_timer, _callback, 0); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0L); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0UL); +timer_setup(&_timer, _callback, 0); | -setup_timer(_timer, _callback, 0); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0L); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0UL); +timer_setup(_timer, _callback, 0); ) @change_callback_unused_data depends on match_timer_function_unused_data@ identifier match_timer_function_unused_data._callback; type _origtype; identifier _origarg; @@ void _callback( -_origtype _origarg +struct timer_list *unused ) { ... when != _origarg } Signed-off-by: Kees Cook <keescook@chromium.org>
2017-10-17 04:43:17 +07:00
timer_setup(&qh->unreserve_timer, dwc2_unreserve_timer_fn, 0);
qh->ep_type = ep_type;
qh->ep_is_in = ep_is_in;
qh->data_toggle = DWC2_HC_PID_DATA0;
qh->maxp = maxp;
INIT_LIST_HEAD(&qh->qtd_list);
INIT_LIST_HEAD(&qh->qh_list_entry);
qh->do_split = do_split;
qh->dev_speed = dev_speed;
if (ep_is_int || ep_is_isoc) {
/* Compute scheduling parameters once and save them */
int host_speed = do_split ? USB_SPEED_HIGH : dev_speed;
struct dwc2_tt *dwc_tt = dwc2_host_get_tt_info(hsotg, urb->priv,
mem_flags,
&qh->ttport);
int device_ns;
qh->dwc_tt = dwc_tt;
qh->host_us = NS_TO_US(usb_calc_bus_time(host_speed, ep_is_in,
ep_is_isoc, bytecount));
device_ns = usb_calc_bus_time(dev_speed, ep_is_in,
ep_is_isoc, bytecount);
if (do_split && dwc_tt)
device_ns += dwc_tt->usb_tt->think_time;
qh->device_us = NS_TO_US(device_ns);
qh->device_interval = urb->interval;
qh->host_interval = urb->interval * (do_split ? 8 : 1);
/*
* Schedule low speed if we're running the host in low or
* full speed OR if we've got a "TT" to deal with to access this
* device.
*/
qh->schedule_low_speed = prtspd != HPRT0_SPD_HIGH_SPEED ||
dwc_tt;
if (do_split) {
/* We won't know num transfers until we schedule */
qh->num_hs_transfers = -1;
} else if (dev_speed == USB_SPEED_HIGH) {
qh->num_hs_transfers = 1;
} else {
qh->num_hs_transfers = 0;
}
/* We'll schedule later when we have something to do */
}
switch (dev_speed) {
case USB_SPEED_LOW:
speed = "low";
break;
case USB_SPEED_FULL:
speed = "full";
break;
case USB_SPEED_HIGH:
speed = "high";
break;
default:
speed = "?";
break;
}
switch (qh->ep_type) {
case USB_ENDPOINT_XFER_ISOC:
type = "isochronous";
break;
case USB_ENDPOINT_XFER_INT:
type = "interrupt";
break;
case USB_ENDPOINT_XFER_CONTROL:
type = "control";
break;
case USB_ENDPOINT_XFER_BULK:
type = "bulk";
break;
default:
type = "?";
break;
}
dwc2_sch_dbg(hsotg, "QH=%p Init %s, %s speed, %d bytes:\n", qh, type,
speed, bytecount);
dwc2_sch_dbg(hsotg, "QH=%p ...addr=%d, ep=%d, %s\n", qh,
dwc2_hcd_get_dev_addr(&urb->pipe_info),
dwc2_hcd_get_ep_num(&urb->pipe_info),
ep_is_in ? "IN" : "OUT");
if (ep_is_int || ep_is_isoc) {
dwc2_sch_dbg(hsotg,
"QH=%p ...duration: host=%d us, device=%d us\n",
qh, qh->host_us, qh->device_us);
dwc2_sch_dbg(hsotg, "QH=%p ...interval: host=%d, device=%d\n",
qh, qh->host_interval, qh->device_interval);
if (qh->schedule_low_speed)
dwc2_sch_dbg(hsotg, "QH=%p ...low speed schedule=%p\n",
qh, dwc2_get_ls_map(hsotg, qh));
}
}
/**
* dwc2_hcd_qh_create() - Allocates and initializes a QH
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @urb: Holds the information about the device/endpoint needed
* to initialize the QH
* @atomic_alloc: Flag to do atomic allocation if needed
*
* Return: Pointer to the newly allocated QH, or NULL on error
*/
struct dwc2_qh *dwc2_hcd_qh_create(struct dwc2_hsotg *hsotg,
struct dwc2_hcd_urb *urb,
gfp_t mem_flags)
{
struct dwc2_qh *qh;
if (!urb->priv)
return NULL;
/* Allocate memory */
qh = kzalloc(sizeof(*qh), mem_flags);
if (!qh)
return NULL;
dwc2_qh_init(hsotg, qh, urb, mem_flags);
if (hsotg->params.dma_desc_enable &&
dwc2_hcd_qh_init_ddma(hsotg, qh, mem_flags) < 0) {
dwc2_hcd_qh_free(hsotg, qh);
return NULL;
}
return qh;
}
/**
* dwc2_hcd_qh_free() - Frees the QH
*
* @hsotg: HCD instance
* @qh: The QH to free
*
* QH should already be removed from the list. QTD list should already be empty
* if called from URB Dequeue.
*
* Must NOT be called with interrupt disabled or spinlock held
*/
void dwc2_hcd_qh_free(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
/* Make sure any unreserve work is finished. */
if (del_timer_sync(&qh->unreserve_timer)) {
unsigned long flags;
spin_lock_irqsave(&hsotg->lock, flags);
dwc2_do_unreserve(hsotg, qh);
spin_unlock_irqrestore(&hsotg->lock, flags);
}
dwc2_host_put_tt_info(hsotg, qh->dwc_tt);
if (qh->desc_list)
dwc2_hcd_qh_free_ddma(hsotg, qh);
kfree(qh);
}
/**
* dwc2_hcd_qh_add() - Adds a QH to either the non periodic or periodic
* schedule if it is not already in the schedule. If the QH is already in
* the schedule, no action is taken.
*
* @hsotg: The HCD state structure for the DWC OTG controller
* @qh: The QH to add
*
* Return: 0 if successful, negative error code otherwise
*/
int dwc2_hcd_qh_add(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
int status;
u32 intr_mask;
if (dbg_qh(qh))
dev_vdbg(hsotg->dev, "%s()\n", __func__);
if (!list_empty(&qh->qh_list_entry))
/* QH already in a schedule */
return 0;
/* Add the new QH to the appropriate schedule */
if (dwc2_qh_is_non_per(qh)) {
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/* Schedule right away */
qh->start_active_frame = hsotg->frame_number;
qh->next_active_frame = qh->start_active_frame;
/* Always start in inactive schedule */
list_add_tail(&qh->qh_list_entry,
&hsotg->non_periodic_sched_inactive);
return 0;
}
status = dwc2_schedule_periodic(hsotg, qh);
if (status)
return status;
if (!hsotg->periodic_qh_count) {
intr_mask = dwc2_readl(hsotg->regs + GINTMSK);
intr_mask |= GINTSTS_SOF;
dwc2_writel(intr_mask, hsotg->regs + GINTMSK);
}
hsotg->periodic_qh_count++;
return 0;
}
/**
* dwc2_hcd_qh_unlink() - Removes a QH from either the non-periodic or periodic
* schedule. Memory is not freed.
*
* @hsotg: The HCD state structure
* @qh: QH to remove from schedule
*/
void dwc2_hcd_qh_unlink(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
u32 intr_mask;
dev_vdbg(hsotg->dev, "%s()\n", __func__);
if (list_empty(&qh->qh_list_entry))
/* QH is not in a schedule */
return;
if (dwc2_qh_is_non_per(qh)) {
if (hsotg->non_periodic_qh_ptr == &qh->qh_list_entry)
hsotg->non_periodic_qh_ptr =
hsotg->non_periodic_qh_ptr->next;
list_del_init(&qh->qh_list_entry);
return;
}
dwc2_deschedule_periodic(hsotg, qh);
hsotg->periodic_qh_count--;
if (!hsotg->periodic_qh_count &&
!hsotg->params.dma_desc_enable) {
intr_mask = dwc2_readl(hsotg->regs + GINTMSK);
intr_mask &= ~GINTSTS_SOF;
dwc2_writel(intr_mask, hsotg->regs + GINTMSK);
}
}
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/**
* dwc2_next_for_periodic_split() - Set next_active_frame midway thru a split.
*
* This is called for setting next_active_frame for periodic splits for all but
* the first packet of the split. Confusing? I thought so...
*
* Periodic splits are single low/full speed transfers that we end up splitting
* up into several high speed transfers. They always fit into one full (1 ms)
* frame but might be split over several microframes (125 us each). We to put
* each of the parts on a very specific high speed frame.
*
* This function figures out where the next active uFrame needs to be.
*
* @hsotg: The HCD state structure
* @qh: QH for the periodic transfer.
* @frame_number: The current frame number.
*
* Return: number missed by (or 0 if we didn't miss).
*/
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
static int dwc2_next_for_periodic_split(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh, u16 frame_number)
{
u16 old_frame = qh->next_active_frame;
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
u16 prev_frame_number = dwc2_frame_num_dec(frame_number, 1);
int missed = 0;
u16 incr;
/*
* See dwc2_uframe_schedule_split() for split scheduling.
*
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
* Basically: increment 1 normally, but 2 right after the start split
* (except for ISOC out).
*/
if (old_frame == qh->start_active_frame &&
!(qh->ep_type == USB_ENDPOINT_XFER_ISOC && !qh->ep_is_in))
incr = 2;
else
incr = 1;
qh->next_active_frame = dwc2_frame_num_inc(old_frame, incr);
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/*
* Note that it's OK for frame_number to be 1 frame past
* next_active_frame. Remember that next_active_frame is supposed to
* be 1 frame _before_ when we want to be scheduled. If we're 1 frame
* past it just means schedule ASAP.
*
* It's _not_ OK, however, if we're more than one frame past.
*/
if (dwc2_frame_num_gt(prev_frame_number, qh->next_active_frame)) {
/*
* OOPS, we missed. That's actually pretty bad since
* the hub will be unhappy; try ASAP I guess.
*/
missed = dwc2_frame_num_dec(prev_frame_number,
qh->next_active_frame);
qh->next_active_frame = frame_number;
}
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
return missed;
}
/**
* dwc2_next_periodic_start() - Set next_active_frame for next transfer start
*
* This is called for setting next_active_frame for a periodic transfer for
* all cases other than midway through a periodic split. This will also update
* start_active_frame.
*
* Since we _always_ keep start_active_frame as the start of the previous
* transfer this is normally pretty easy: we just add our interval to
* start_active_frame and we've got our answer.
*
* The tricks come into play if we miss. In that case we'll look for the next
* slot we can fit into.
*
* @hsotg: The HCD state structure
* @qh: QH for the periodic transfer.
* @frame_number: The current frame number.
*
* Return: number missed by (or 0 if we didn't miss).
*/
static int dwc2_next_periodic_start(struct dwc2_hsotg *hsotg,
struct dwc2_qh *qh, u16 frame_number)
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
{
int missed = 0;
u16 interval = qh->host_interval;
u16 prev_frame_number = dwc2_frame_num_dec(frame_number, 1);
qh->start_active_frame = dwc2_frame_num_inc(qh->start_active_frame,
interval);
/*
* The dwc2_frame_num_gt() function used below won't work terribly well
* with if we just incremented by a really large intervals since the
* frame counter only goes to 0x3fff. It's terribly unlikely that we
* will have missed in this case anyway. Just go to exit. If we want
* to try to do better we'll need to keep track of a bigger counter
* somewhere in the driver and handle overflows.
*/
if (interval >= 0x1000)
goto exit;
/*
* Test for misses, which is when it's too late to schedule.
*
* A few things to note:
* - We compare against prev_frame_number since start_active_frame
* and next_active_frame are always 1 frame before we want things
* to be active and we assume we can still get scheduled in the
* current frame number.
usb: dwc2: host: Properly set even/odd frame When setting up ISO and INT transfers dwc2 needs to specify whether the transfer is for an even or an odd frame (or microframe if the controller is running in high speed mode). The controller appears to use this as a simple way to figure out if a transfer should happen right away (in the current microframe) or should happen at the start of the next microframe. Said another way: - If you set "odd" and the current frame number is odd it appears that the controller will try to transfer right away. Same thing if you set "even" and the current frame number is even. - If the oddness you set and the oddness of the frame number are _different_, the transfer will be delayed until the frame number changes. As I understand it, the above technique allows you to plan ahead of time where possible by always working on the next frame. ...but it still allows you to properly respond immediately to things that happened in the previous frame. The old dwc2_hc_set_even_odd_frame() didn't really handle this concept. It always looked at the frame number and setup the transfer to happen in the next frame. In some cases that meant that certain transactions would be transferred in the wrong frame. We'll try our best to set the even / odd to do the transfer in the scheduled frame. If that fails then we'll do an ugly "schedule ASAP". We'll also modify the scheduler code to handle this and not try to schedule a second transfer for the same frame. Note that this change relies on the work to redo the microframe scheduler. It can work atop ("usb: dwc2: host: Manage frame nums better in scheduler") but it works even better after ("usb: dwc2: host: Totally redo the microframe scheduler"). With this change my stressful USB test (USB webcam + USB audio + keyboards) has less audio crackling than before. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:11 +07:00
* - It's possible for start_active_frame (now incremented) to be
* next_active_frame if we got an EO MISS (even_odd miss) which
* basically means that we detected there wasn't enough time for
* the last packet and dwc2_hc_set_even_odd_frame() rescheduled us
* at the last second. We want to make sure we don't schedule
* another transfer for the same frame. My test webcam doesn't seem
* terribly upset by missing a transfer but really doesn't like when
* we do two transfers in the same frame.
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
* - Some misses are expected. Specifically, in order to work
* perfectly dwc2 really needs quite spectacular interrupt latency
* requirements. It needs to be able to handle its interrupts
* completely within 125 us of them being asserted. That not only
* means that the dwc2 interrupt handler needs to be fast but it
* means that nothing else in the system has to block dwc2 for a long
* time. We can help with the dwc2 parts of this, but it's hard to
* guarantee that a system will have interrupt latency < 125 us, so
* we have to be robust to some misses.
*/
usb: dwc2: host: Properly set even/odd frame When setting up ISO and INT transfers dwc2 needs to specify whether the transfer is for an even or an odd frame (or microframe if the controller is running in high speed mode). The controller appears to use this as a simple way to figure out if a transfer should happen right away (in the current microframe) or should happen at the start of the next microframe. Said another way: - If you set "odd" and the current frame number is odd it appears that the controller will try to transfer right away. Same thing if you set "even" and the current frame number is even. - If the oddness you set and the oddness of the frame number are _different_, the transfer will be delayed until the frame number changes. As I understand it, the above technique allows you to plan ahead of time where possible by always working on the next frame. ...but it still allows you to properly respond immediately to things that happened in the previous frame. The old dwc2_hc_set_even_odd_frame() didn't really handle this concept. It always looked at the frame number and setup the transfer to happen in the next frame. In some cases that meant that certain transactions would be transferred in the wrong frame. We'll try our best to set the even / odd to do the transfer in the scheduled frame. If that fails then we'll do an ugly "schedule ASAP". We'll also modify the scheduler code to handle this and not try to schedule a second transfer for the same frame. Note that this change relies on the work to redo the microframe scheduler. It can work atop ("usb: dwc2: host: Manage frame nums better in scheduler") but it works even better after ("usb: dwc2: host: Totally redo the microframe scheduler"). With this change my stressful USB test (USB webcam + USB audio + keyboards) has less audio crackling than before. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:11 +07:00
if (qh->start_active_frame == qh->next_active_frame ||
dwc2_frame_num_gt(prev_frame_number, qh->start_active_frame)) {
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
u16 ideal_start = qh->start_active_frame;
int periods_in_map;
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/*
* Adjust interval as per gcd with map size.
* See pmap_schedule() for more details here.
*/
if (qh->do_split || qh->dev_speed == USB_SPEED_HIGH)
periods_in_map = DWC2_HS_SCHEDULE_UFRAMES;
else
periods_in_map = DWC2_LS_SCHEDULE_FRAMES;
interval = gcd(interval, periods_in_map);
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
do {
qh->start_active_frame = dwc2_frame_num_inc(
qh->start_active_frame, interval);
} while (dwc2_frame_num_gt(prev_frame_number,
qh->start_active_frame));
missed = dwc2_frame_num_dec(qh->start_active_frame,
ideal_start);
}
exit:
qh->next_active_frame = qh->start_active_frame;
return missed;
}
/*
* Deactivates a QH. For non-periodic QHs, removes the QH from the active
* non-periodic schedule. The QH is added to the inactive non-periodic
* schedule if any QTDs are still attached to the QH.
*
* For periodic QHs, the QH is removed from the periodic queued schedule. If
* there are any QTDs still attached to the QH, the QH is added to either the
* periodic inactive schedule or the periodic ready schedule and its next
* scheduled frame is calculated. The QH is placed in the ready schedule if
* the scheduled frame has been reached already. Otherwise it's placed in the
* inactive schedule. If there are no QTDs attached to the QH, the QH is
* completely removed from the periodic schedule.
*/
void dwc2_hcd_qh_deactivate(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
int sched_next_periodic_split)
{
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
u16 old_frame = qh->next_active_frame;
u16 frame_number;
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
int missed;
if (dbg_qh(qh))
dev_vdbg(hsotg->dev, "%s()\n", __func__);
if (dwc2_qh_is_non_per(qh)) {
dwc2_hcd_qh_unlink(hsotg, qh);
if (!list_empty(&qh->qtd_list))
/* Add back to inactive non-periodic schedule */
dwc2_hcd_qh_add(hsotg, qh);
return;
}
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/*
* Use the real frame number rather than the cached value as of the
* last SOF just to get us a little closer to reality. Note that
* means we don't actually know if we've already handled the SOF
* interrupt for this frame.
*/
frame_number = dwc2_hcd_get_frame_number(hsotg);
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
if (sched_next_periodic_split)
missed = dwc2_next_for_periodic_split(hsotg, qh, frame_number);
else
missed = dwc2_next_periodic_start(hsotg, qh, frame_number);
dwc2_sch_vdbg(hsotg,
"QH=%p next(%d) fn=%04x, sch=%04x=>%04x (%+d) miss=%d %s\n",
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
qh, sched_next_periodic_split, frame_number, old_frame,
qh->next_active_frame,
dwc2_frame_num_dec(qh->next_active_frame, old_frame),
missed, missed ? "MISS" : "");
if (list_empty(&qh->qtd_list)) {
dwc2_hcd_qh_unlink(hsotg, qh);
return;
}
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
/*
* Remove from periodic_sched_queued and move to
* appropriate queue
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
*
* Note: we purposely use the frame_number from the "hsotg" structure
* since we know SOF interrupt will handle future frames.
*/
usb: dwc2: host: Manage frame nums better in scheduler The dwc2 scheduler (contained in hcd_queue.c) was a bit confusing in the way it initted / kept track of which frames a QH was going to be active in. Let's clean things up a little bit in preparation for a rewrite of the microframe scheduler. Specifically: * Old code would pick a frame number in dwc2_qh_init() and would try to pick it "in a slightly future (micro)frame". As far as I can tell the reason for this was that there was a delay between dwc2_qh_init() and when we actually wanted to dwc2_hcd_qh_add(). ...but apparently this attempt to be slightly in the future wasn't enough because dwc2_hcd_qh_add() then had code to reset things if the frame _wasn't_ in the future. There's no reason not to just pick the frame later. For non-periodic QH we now pick the frame in dwc2_hcd_qh_add(). For periodic QH we pick the frame at dwc2_schedule_periodic() time. * The old "dwc2_qh_init() actually assigned to "hsotg->frame_number". This doesn't seem like a great idea since that variable is supposed to be used to keep track of which SOF the interrupt handler has seen. Let's be clean: anyone who wants the current frame number (instead of the one as of the last interrupt) should ask for it. * The old code wasn't terribly consistent about trying to use the frame that the microframe scheduler assigned to it. In dwc2_sched_periodic_split() when it was scheduling the first frame it always "ORed" in 0x7 (!). Since the frame goes on the wire 1 uFrame after next_active_frame it meant that the SSPLIT would always try for uFrame 0 and the transaction would happen on the low speed bus during uFrame 1. This is irregardless of what the microframe scheduler said. * The old code assumed it would get called to schedule the next in a periodic split very quickly. That is if next_active_frame was 0 (transfer on wire in uFrame 1) it assumed it was getting called to schedule the next uFrame during uFrame 1 too (so it could queue something up for uFrame 2). It should be possible to actually queue something up for uFrame 2 while in uFrame 2 (AKA queue up ASAP). To do this, code needs to look at the previously scheduled frame when deciding when to next be active, not look at the current frame number. * If there was no microframe scheduler, the old code would check for whether we should be active using "qh->next_active_frame == frame_number". This seemed like a race waiting to happen. ...plus there's no way that you wouldn't want to schedule if next_active_frame was actually less than frame number. Note that this change doesn't make 100% sense on its own since it's expecting some sanity in the frame numbers assigned by the microframe scheduler and (as per the future patch which rewries it) I think that the current microframe scheduler is quite insane. However, it seems like splitting this up from the microframe scheduler patch makes things into smaller chunks and hopefully adds to clarity rather than reduces it. The two patches could certainly be squashed. Not that in the very least, I don't see any obvious bad behavior introduced with just this patch. I've attempted to keep the config parameter to disable the microframe scheduler in tact in this change, though I'm not sure it's worth it. Obviously the code is touched a lot so it's possible I regressed something when the microframe scheduler is disabled, though I did some basic testing and it seemed to work OK. I'm still not 100% sure why you wouldn't want the microframe scheduler (presuming it works), so maybe a future patch (or a future version of this patch?) could remove that parameter. Acked-by: John Youn <johnyoun@synopsys.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-01-29 09:20:08 +07:00
if (dwc2_frame_num_le(qh->next_active_frame, hsotg->frame_number))
list_move_tail(&qh->qh_list_entry,
&hsotg->periodic_sched_ready);
else
list_move_tail(&qh->qh_list_entry,
&hsotg->periodic_sched_inactive);
}
/**
* dwc2_hcd_qtd_init() - Initializes a QTD structure
*
* @qtd: The QTD to initialize
* @urb: The associated URB
*/
void dwc2_hcd_qtd_init(struct dwc2_qtd *qtd, struct dwc2_hcd_urb *urb)
{
qtd->urb = urb;
if (dwc2_hcd_get_pipe_type(&urb->pipe_info) ==
USB_ENDPOINT_XFER_CONTROL) {
/*
* The only time the QTD data toggle is used is on the data
* phase of control transfers. This phase always starts with
* DATA1.
*/
qtd->data_toggle = DWC2_HC_PID_DATA1;
qtd->control_phase = DWC2_CONTROL_SETUP;
}
/* Start split */
qtd->complete_split = 0;
qtd->isoc_split_pos = DWC2_HCSPLT_XACTPOS_ALL;
qtd->isoc_split_offset = 0;
qtd->in_process = 0;
/* Store the qtd ptr in the urb to reference the QTD */
urb->qtd = qtd;
}
/**
* dwc2_hcd_qtd_add() - Adds a QTD to the QTD-list of a QH
* Caller must hold driver lock.
*
* @hsotg: The DWC HCD structure
* @qtd: The QTD to add
* @qh: Queue head to add qtd to
*
* Return: 0 if successful, negative error code otherwise
*
* If the QH to which the QTD is added is not currently scheduled, it is placed
* into the proper schedule based on its EP type.
*/
int dwc2_hcd_qtd_add(struct dwc2_hsotg *hsotg, struct dwc2_qtd *qtd,
struct dwc2_qh *qh)
{
int retval;
if (unlikely(!qh)) {
dev_err(hsotg->dev, "%s: Invalid QH\n", __func__);
retval = -EINVAL;
goto fail;
}
retval = dwc2_hcd_qh_add(hsotg, qh);
if (retval)
goto fail;
qtd->qh = qh;
list_add_tail(&qtd->qtd_list_entry, &qh->qtd_list);
return 0;
fail:
return retval;
}