linux_dsm_epyc7002/drivers/usb/host/ehci-sched.c

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/*
* Copyright (c) 2001-2004 by David Brownell
* Copyright (c) 2003 Michal Sojka, for high-speed iso transfers
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* this file is part of ehci-hcd.c */
/*-------------------------------------------------------------------------*/
/*
* EHCI scheduled transaction support: interrupt, iso, split iso
* These are called "periodic" transactions in the EHCI spec.
*
* Note that for interrupt transfers, the QH/QTD manipulation is shared
* with the "asynchronous" transaction support (control/bulk transfers).
* The only real difference is in how interrupt transfers are scheduled.
*
* For ISO, we make an "iso_stream" head to serve the same role as a QH.
* It keeps track of every ITD (or SITD) that's linked, and holds enough
* pre-calculated schedule data to make appending to the queue be quick.
*/
static int ehci_get_frame (struct usb_hcd *hcd);
/*
* periodic_next_shadow - return "next" pointer on shadow list
* @periodic: host pointer to qh/itd/sitd
* @tag: hardware tag for type of this record
*/
static union ehci_shadow *
periodic_next_shadow(struct ehci_hcd *ehci, union ehci_shadow *periodic,
__hc32 tag)
{
switch (hc32_to_cpu(ehci, tag)) {
case Q_TYPE_QH:
return &periodic->qh->qh_next;
case Q_TYPE_FSTN:
return &periodic->fstn->fstn_next;
case Q_TYPE_ITD:
return &periodic->itd->itd_next;
// case Q_TYPE_SITD:
default:
return &periodic->sitd->sitd_next;
}
}
static __hc32 *
shadow_next_periodic(struct ehci_hcd *ehci, union ehci_shadow *periodic,
__hc32 tag)
{
switch (hc32_to_cpu(ehci, tag)) {
/* our ehci_shadow.qh is actually software part */
case Q_TYPE_QH:
return &periodic->qh->hw->hw_next;
/* others are hw parts */
default:
return periodic->hw_next;
}
}
/* caller must hold ehci->lock */
static void periodic_unlink (struct ehci_hcd *ehci, unsigned frame, void *ptr)
{
union ehci_shadow *prev_p = &ehci->pshadow[frame];
__hc32 *hw_p = &ehci->periodic[frame];
union ehci_shadow here = *prev_p;
/* find predecessor of "ptr"; hw and shadow lists are in sync */
while (here.ptr && here.ptr != ptr) {
prev_p = periodic_next_shadow(ehci, prev_p,
Q_NEXT_TYPE(ehci, *hw_p));
hw_p = shadow_next_periodic(ehci, &here,
Q_NEXT_TYPE(ehci, *hw_p));
here = *prev_p;
}
/* an interrupt entry (at list end) could have been shared */
if (!here.ptr)
return;
/* update shadow and hardware lists ... the old "next" pointers
* from ptr may still be in use, the caller updates them.
*/
*prev_p = *periodic_next_shadow(ehci, &here,
Q_NEXT_TYPE(ehci, *hw_p));
if (!ehci->use_dummy_qh ||
*shadow_next_periodic(ehci, &here, Q_NEXT_TYPE(ehci, *hw_p))
!= EHCI_LIST_END(ehci))
*hw_p = *shadow_next_periodic(ehci, &here,
Q_NEXT_TYPE(ehci, *hw_p));
else
*hw_p = cpu_to_hc32(ehci, ehci->dummy->qh_dma);
}
/*-------------------------------------------------------------------------*/
/* Bandwidth and TT management */
/* Find the TT data structure for this device; create it if necessary */
static struct ehci_tt *find_tt(struct usb_device *udev)
{
struct usb_tt *utt = udev->tt;
struct ehci_tt *tt, **tt_index, **ptt;
unsigned port;
bool allocated_index = false;
if (!utt)
return NULL; /* Not below a TT */
/*
* Find/create our data structure.
* For hubs with a single TT, we get it directly.
* For hubs with multiple TTs, there's an extra level of pointers.
*/
tt_index = NULL;
if (utt->multi) {
tt_index = utt->hcpriv;
if (!tt_index) { /* Create the index array */
tt_index = kzalloc(utt->hub->maxchild *
sizeof(*tt_index), GFP_ATOMIC);
if (!tt_index)
return ERR_PTR(-ENOMEM);
utt->hcpriv = tt_index;
allocated_index = true;
}
port = udev->ttport - 1;
ptt = &tt_index[port];
} else {
port = 0;
ptt = (struct ehci_tt **) &utt->hcpriv;
}
tt = *ptt;
if (!tt) { /* Create the ehci_tt */
struct ehci_hcd *ehci =
hcd_to_ehci(bus_to_hcd(udev->bus));
tt = kzalloc(sizeof(*tt), GFP_ATOMIC);
if (!tt) {
if (allocated_index) {
utt->hcpriv = NULL;
kfree(tt_index);
}
return ERR_PTR(-ENOMEM);
}
list_add_tail(&tt->tt_list, &ehci->tt_list);
INIT_LIST_HEAD(&tt->ps_list);
tt->usb_tt = utt;
tt->tt_port = port;
*ptt = tt;
}
return tt;
}
/* Release the TT above udev, if it's not in use */
static void drop_tt(struct usb_device *udev)
{
struct usb_tt *utt = udev->tt;
struct ehci_tt *tt, **tt_index, **ptt;
int cnt, i;
if (!utt || !utt->hcpriv)
return; /* Not below a TT, or never allocated */
cnt = 0;
if (utt->multi) {
tt_index = utt->hcpriv;
ptt = &tt_index[udev->ttport - 1];
/* How many entries are left in tt_index? */
for (i = 0; i < utt->hub->maxchild; ++i)
cnt += !!tt_index[i];
} else {
tt_index = NULL;
ptt = (struct ehci_tt **) &utt->hcpriv;
}
tt = *ptt;
if (!tt || !list_empty(&tt->ps_list))
return; /* never allocated, or still in use */
list_del(&tt->tt_list);
*ptt = NULL;
kfree(tt);
if (cnt == 1) {
utt->hcpriv = NULL;
kfree(tt_index);
}
}
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
static void bandwidth_dbg(struct ehci_hcd *ehci, int sign, char *type,
struct ehci_per_sched *ps)
{
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
dev_dbg(&ps->udev->dev,
"ep %02x: %s %s @ %u+%u (%u.%u+%u) [%u/%u us] mask %04x\n",
ps->ep->desc.bEndpointAddress,
(sign >= 0 ? "reserve" : "release"), type,
(ps->bw_phase << 3) + ps->phase_uf, ps->bw_uperiod,
ps->phase, ps->phase_uf, ps->period,
ps->usecs, ps->c_usecs, ps->cs_mask);
}
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
static void reserve_release_intr_bandwidth(struct ehci_hcd *ehci,
struct ehci_qh *qh, int sign)
{
unsigned start_uf;
unsigned i, j, m;
int usecs = qh->ps.usecs;
int c_usecs = qh->ps.c_usecs;
int tt_usecs = qh->ps.tt_usecs;
struct ehci_tt *tt;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (qh->ps.phase == NO_FRAME) /* Bandwidth wasn't reserved */
return;
start_uf = qh->ps.bw_phase << 3;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
bandwidth_dbg(ehci, sign, "intr", &qh->ps);
if (sign < 0) { /* Release bandwidth */
usecs = -usecs;
c_usecs = -c_usecs;
tt_usecs = -tt_usecs;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
}
/* Entire transaction (high speed) or start-split (full/low speed) */
for (i = start_uf + qh->ps.phase_uf; i < EHCI_BANDWIDTH_SIZE;
i += qh->ps.bw_uperiod)
ehci->bandwidth[i] += usecs;
/* Complete-split (full/low speed) */
if (qh->ps.c_usecs) {
/* NOTE: adjustments needed for FSTN */
for (i = start_uf; i < EHCI_BANDWIDTH_SIZE;
i += qh->ps.bw_uperiod) {
for ((j = 2, m = 1 << (j+8)); j < 8; (++j, m <<= 1)) {
if (qh->ps.cs_mask & m)
ehci->bandwidth[i+j] += c_usecs;
}
}
}
/* FS/LS bus bandwidth */
if (tt_usecs) {
tt = find_tt(qh->ps.udev);
if (sign > 0)
list_add_tail(&qh->ps.ps_list, &tt->ps_list);
else
list_del(&qh->ps.ps_list);
for (i = start_uf >> 3; i < EHCI_BANDWIDTH_FRAMES;
i += qh->ps.bw_period)
tt->bandwidth[i] += tt_usecs;
}
}
/*-------------------------------------------------------------------------*/
static void compute_tt_budget(u8 budget_table[EHCI_BANDWIDTH_SIZE],
struct ehci_tt *tt)
{
struct ehci_per_sched *ps;
unsigned uframe, uf, x;
u8 *budget_line;
if (!tt)
return;
memset(budget_table, 0, EHCI_BANDWIDTH_SIZE);
/* Add up the contributions from all the endpoints using this TT */
list_for_each_entry(ps, &tt->ps_list, ps_list) {
for (uframe = ps->bw_phase << 3; uframe < EHCI_BANDWIDTH_SIZE;
uframe += ps->bw_uperiod) {
budget_line = &budget_table[uframe];
x = ps->tt_usecs;
/* propagate the time forward */
for (uf = ps->phase_uf; uf < 8; ++uf) {
x += budget_line[uf];
/* Each microframe lasts 125 us */
if (x <= 125) {
budget_line[uf] = x;
break;
} else {
budget_line[uf] = 125;
x -= 125;
}
}
}
}
}
static int __maybe_unused same_tt(struct usb_device *dev1,
struct usb_device *dev2)
{
if (!dev1->tt || !dev2->tt)
return 0;
if (dev1->tt != dev2->tt)
return 0;
if (dev1->tt->multi)
return dev1->ttport == dev2->ttport;
else
return 1;
}
#ifdef CONFIG_USB_EHCI_TT_NEWSCHED
/* Which uframe does the low/fullspeed transfer start in?
*
* The parameter is the mask of ssplits in "H-frame" terms
* and this returns the transfer start uframe in "B-frame" terms,
* which allows both to match, e.g. a ssplit in "H-frame" uframe 0
* will cause a transfer in "B-frame" uframe 0. "B-frames" lag
* "H-frames" by 1 uframe. See the EHCI spec sec 4.5 and figure 4.7.
*/
static inline unsigned char tt_start_uframe(struct ehci_hcd *ehci, __hc32 mask)
{
unsigned char smask = QH_SMASK & hc32_to_cpu(ehci, mask);
if (!smask) {
ehci_err(ehci, "invalid empty smask!\n");
/* uframe 7 can't have bw so this will indicate failure */
return 7;
}
return ffs(smask) - 1;
}
static const unsigned char
max_tt_usecs[] = { 125, 125, 125, 125, 125, 125, 30, 0 };
/* carryover low/fullspeed bandwidth that crosses uframe boundries */
static inline void carryover_tt_bandwidth(unsigned short tt_usecs[8])
{
int i;
for (i=0; i<7; i++) {
if (max_tt_usecs[i] < tt_usecs[i]) {
tt_usecs[i+1] += tt_usecs[i] - max_tt_usecs[i];
tt_usecs[i] = max_tt_usecs[i];
}
}
}
/*
* Return true if the device's tt's downstream bus is available for a
* periodic transfer of the specified length (usecs), starting at the
* specified frame/uframe. Note that (as summarized in section 11.19
* of the usb 2.0 spec) TTs can buffer multiple transactions for each
* uframe.
*
* The uframe parameter is when the fullspeed/lowspeed transfer
* should be executed in "B-frame" terms, which is the same as the
* highspeed ssplit's uframe (which is in "H-frame" terms). For example
* a ssplit in "H-frame" 0 causes a transfer in "B-frame" 0.
* See the EHCI spec sec 4.5 and fig 4.7.
*
* This checks if the full/lowspeed bus, at the specified starting uframe,
* has the specified bandwidth available, according to rules listed
* in USB 2.0 spec section 11.18.1 fig 11-60.
*
* This does not check if the transfer would exceed the max ssplit
* limit of 16, specified in USB 2.0 spec section 11.18.4 requirement #4,
* since proper scheduling limits ssplits to less than 16 per uframe.
*/
static int tt_available (
struct ehci_hcd *ehci,
struct ehci_per_sched *ps,
struct ehci_tt *tt,
unsigned frame,
unsigned uframe
)
{
unsigned period = ps->bw_period;
unsigned usecs = ps->tt_usecs;
if ((period == 0) || (uframe >= 7)) /* error */
return 0;
for (frame &= period - 1; frame < EHCI_BANDWIDTH_FRAMES;
frame += period) {
unsigned i, uf;
unsigned short tt_usecs[8];
if (tt->bandwidth[frame] + usecs > 900)
return 0;
uf = frame << 3;
for (i = 0; i < 8; (++i, ++uf))
tt_usecs[i] = ehci->tt_budget[uf];
if (max_tt_usecs[uframe] <= tt_usecs[uframe])
return 0;
/* special case for isoc transfers larger than 125us:
* the first and each subsequent fully used uframe
* must be empty, so as to not illegally delay
* already scheduled transactions
*/
if (125 < usecs) {
int ufs = (usecs / 125);
for (i = uframe; i < (uframe + ufs) && i < 8; i++)
if (0 < tt_usecs[i])
return 0;
}
tt_usecs[uframe] += usecs;
carryover_tt_bandwidth(tt_usecs);
/* fail if the carryover pushed bw past the last uframe's limit */
if (max_tt_usecs[7] < tt_usecs[7])
return 0;
}
return 1;
}
#else
/* return true iff the device's transaction translator is available
* for a periodic transfer starting at the specified frame, using
* all the uframes in the mask.
*/
static int tt_no_collision (
struct ehci_hcd *ehci,
unsigned period,
struct usb_device *dev,
unsigned frame,
u32 uf_mask
)
{
if (period == 0) /* error */
return 0;
/* note bandwidth wastage: split never follows csplit
* (different dev or endpoint) until the next uframe.
* calling convention doesn't make that distinction.
*/
for (; frame < ehci->periodic_size; frame += period) {
union ehci_shadow here;
__hc32 type;
struct ehci_qh_hw *hw;
here = ehci->pshadow [frame];
type = Q_NEXT_TYPE(ehci, ehci->periodic [frame]);
while (here.ptr) {
switch (hc32_to_cpu(ehci, type)) {
case Q_TYPE_ITD:
type = Q_NEXT_TYPE(ehci, here.itd->hw_next);
here = here.itd->itd_next;
continue;
case Q_TYPE_QH:
hw = here.qh->hw;
if (same_tt(dev, here.qh->ps.udev)) {
u32 mask;
mask = hc32_to_cpu(ehci,
hw->hw_info2);
/* "knows" no gap is needed */
mask |= mask >> 8;
if (mask & uf_mask)
break;
}
type = Q_NEXT_TYPE(ehci, hw->hw_next);
here = here.qh->qh_next;
continue;
case Q_TYPE_SITD:
if (same_tt (dev, here.sitd->urb->dev)) {
u16 mask;
mask = hc32_to_cpu(ehci, here.sitd
->hw_uframe);
/* FIXME assumes no gap for IN! */
mask |= mask >> 8;
if (mask & uf_mask)
break;
}
type = Q_NEXT_TYPE(ehci, here.sitd->hw_next);
here = here.sitd->sitd_next;
continue;
// case Q_TYPE_FSTN:
default:
ehci_dbg (ehci,
"periodic frame %d bogus type %d\n",
frame, type);
}
/* collision or error */
return 0;
}
}
/* no collision */
return 1;
}
#endif /* CONFIG_USB_EHCI_TT_NEWSCHED */
/*-------------------------------------------------------------------------*/
static void enable_periodic(struct ehci_hcd *ehci)
{
if (ehci->periodic_count++)
return;
/* Stop waiting to turn off the periodic schedule */
ehci->enabled_hrtimer_events &= ~BIT(EHCI_HRTIMER_DISABLE_PERIODIC);
/* Don't start the schedule until PSS is 0 */
ehci_poll_PSS(ehci);
turn_on_io_watchdog(ehci);
}
static void disable_periodic(struct ehci_hcd *ehci)
{
if (--ehci->periodic_count)
return;
/* Don't turn off the schedule until PSS is 1 */
ehci_poll_PSS(ehci);
}
/*-------------------------------------------------------------------------*/
/* periodic schedule slots have iso tds (normal or split) first, then a
* sparse tree for active interrupt transfers.
*
* this just links in a qh; caller guarantees uframe masks are set right.
* no FSTN support (yet; ehci 0.96+)
*/
static void qh_link_periodic(struct ehci_hcd *ehci, struct ehci_qh *qh)
{
unsigned i;
unsigned period = qh->ps.period;
dev_dbg(&qh->ps.udev->dev,
"link qh%d-%04x/%p start %d [%d/%d us]\n",
period, hc32_to_cpup(ehci, &qh->hw->hw_info2)
& (QH_CMASK | QH_SMASK),
qh, qh->ps.phase, qh->ps.usecs, qh->ps.c_usecs);
/* high bandwidth, or otherwise every microframe */
if (period == 0)
period = 1;
for (i = qh->ps.phase; i < ehci->periodic_size; i += period) {
union ehci_shadow *prev = &ehci->pshadow[i];
__hc32 *hw_p = &ehci->periodic[i];
union ehci_shadow here = *prev;
__hc32 type = 0;
/* skip the iso nodes at list head */
while (here.ptr) {
type = Q_NEXT_TYPE(ehci, *hw_p);
if (type == cpu_to_hc32(ehci, Q_TYPE_QH))
break;
prev = periodic_next_shadow(ehci, prev, type);
hw_p = shadow_next_periodic(ehci, &here, type);
here = *prev;
}
/* sorting each branch by period (slow-->fast)
* enables sharing interior tree nodes
*/
while (here.ptr && qh != here.qh) {
if (qh->ps.period > here.qh->ps.period)
break;
prev = &here.qh->qh_next;
hw_p = &here.qh->hw->hw_next;
here = *prev;
}
/* link in this qh, unless some earlier pass did that */
if (qh != here.qh) {
qh->qh_next = here;
if (here.qh)
qh->hw->hw_next = *hw_p;
wmb ();
prev->qh = qh;
*hw_p = QH_NEXT (ehci, qh->qh_dma);
}
}
qh->qh_state = QH_STATE_LINKED;
qh->xacterrs = 0;
qh->unlink_reason = 0;
/* update per-qh bandwidth for debugfs */
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
ehci_to_hcd(ehci)->self.bandwidth_allocated += qh->ps.bw_period
? ((qh->ps.usecs + qh->ps.c_usecs) / qh->ps.bw_period)
: (qh->ps.usecs * 8);
list_add(&qh->intr_node, &ehci->intr_qh_list);
/* maybe enable periodic schedule processing */
++ehci->intr_count;
enable_periodic(ehci);
}
static void qh_unlink_periodic(struct ehci_hcd *ehci, struct ehci_qh *qh)
{
unsigned i;
unsigned period;
/*
* If qh is for a low/full-speed device, simply unlinking it
* could interfere with an ongoing split transaction. To unlink
* it safely would require setting the QH_INACTIVATE bit and
* waiting at least one frame, as described in EHCI 4.12.2.5.
*
* We won't bother with any of this. Instead, we assume that the
* only reason for unlinking an interrupt QH while the current URB
* is still active is to dequeue all the URBs (flush the whole
* endpoint queue).
*
* If rebalancing the periodic schedule is ever implemented, this
* approach will no longer be valid.
*/
/* high bandwidth, or otherwise part of every microframe */
period = qh->ps.period ? : 1;
for (i = qh->ps.phase; i < ehci->periodic_size; i += period)
periodic_unlink (ehci, i, qh);
/* update per-qh bandwidth for debugfs */
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
ehci_to_hcd(ehci)->self.bandwidth_allocated -= qh->ps.bw_period
? ((qh->ps.usecs + qh->ps.c_usecs) / qh->ps.bw_period)
: (qh->ps.usecs * 8);
dev_dbg(&qh->ps.udev->dev,
"unlink qh%d-%04x/%p start %d [%d/%d us]\n",
qh->ps.period,
hc32_to_cpup(ehci, &qh->hw->hw_info2) & (QH_CMASK | QH_SMASK),
qh, qh->ps.phase, qh->ps.usecs, qh->ps.c_usecs);
/* qh->qh_next still "live" to HC */
qh->qh_state = QH_STATE_UNLINK;
qh->qh_next.ptr = NULL;
if (ehci->qh_scan_next == qh)
ehci->qh_scan_next = list_entry(qh->intr_node.next,
struct ehci_qh, intr_node);
list_del(&qh->intr_node);
}
static void cancel_unlink_wait_intr(struct ehci_hcd *ehci, struct ehci_qh *qh)
{
if (qh->qh_state != QH_STATE_LINKED ||
list_empty(&qh->unlink_node))
return;
list_del_init(&qh->unlink_node);
/*
* TODO: disable the event of EHCI_HRTIMER_START_UNLINK_INTR for
* avoiding unnecessary CPU wakeup
*/
}
static void start_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh)
{
/* If the QH isn't linked then there's nothing we can do. */
if (qh->qh_state != QH_STATE_LINKED)
return;
/* if the qh is waiting for unlink, cancel it now */
cancel_unlink_wait_intr(ehci, qh);
qh_unlink_periodic (ehci, qh);
/* Make sure the unlinks are visible before starting the timer */
wmb();
/*
* The EHCI spec doesn't say how long it takes the controller to
* stop accessing an unlinked interrupt QH. The timer delay is
* 9 uframes; presumably that will be long enough.
*/
qh->unlink_cycle = ehci->intr_unlink_cycle;
/* New entries go at the end of the intr_unlink list */
list_add_tail(&qh->unlink_node, &ehci->intr_unlink);
if (ehci->intr_unlinking)
; /* Avoid recursive calls */
else if (ehci->rh_state < EHCI_RH_RUNNING)
ehci_handle_intr_unlinks(ehci);
else if (ehci->intr_unlink.next == &qh->unlink_node) {
ehci_enable_event(ehci, EHCI_HRTIMER_UNLINK_INTR, true);
++ehci->intr_unlink_cycle;
}
}
/*
* It is common only one intr URB is scheduled on one qh, and
* given complete() is run in tasklet context, introduce a bit
* delay to avoid unlink qh too early.
*/
static void start_unlink_intr_wait(struct ehci_hcd *ehci,
struct ehci_qh *qh)
{
qh->unlink_cycle = ehci->intr_unlink_wait_cycle;
/* New entries go at the end of the intr_unlink_wait list */
list_add_tail(&qh->unlink_node, &ehci->intr_unlink_wait);
if (ehci->rh_state < EHCI_RH_RUNNING)
ehci_handle_start_intr_unlinks(ehci);
else if (ehci->intr_unlink_wait.next == &qh->unlink_node) {
ehci_enable_event(ehci, EHCI_HRTIMER_START_UNLINK_INTR, true);
++ehci->intr_unlink_wait_cycle;
}
}
static void end_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh)
{
struct ehci_qh_hw *hw = qh->hw;
int rc;
qh->qh_state = QH_STATE_IDLE;
hw->hw_next = EHCI_LIST_END(ehci);
if (!list_empty(&qh->qtd_list))
qh_completions(ehci, qh);
/* reschedule QH iff another request is queued */
if (!list_empty(&qh->qtd_list) && ehci->rh_state == EHCI_RH_RUNNING) {
rc = qh_schedule(ehci, qh);
if (rc == 0) {
qh_refresh(ehci, qh);
qh_link_periodic(ehci, qh);
}
/* An error here likely indicates handshake failure
* or no space left in the schedule. Neither fault
* should happen often ...
*
* FIXME kill the now-dysfunctional queued urbs
*/
else {
ehci_err(ehci, "can't reschedule qh %p, err %d\n",
qh, rc);
}
}
/* maybe turn off periodic schedule */
--ehci->intr_count;
disable_periodic(ehci);
}
/*-------------------------------------------------------------------------*/
static int check_period (
struct ehci_hcd *ehci,
unsigned frame,
unsigned uframe,
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
unsigned uperiod,
unsigned usecs
) {
/* complete split running into next frame?
* given FSTN support, we could sometimes check...
*/
if (uframe >= 8)
return 0;
USB: EHCI: Allow users to override 80% max periodic bandwidth There are cases, when 80% max isochronous bandwidth is too limiting. For example I have two USB video capture cards which stream uncompressed video, and to stream full NTSC + PAL videos we'd need NTSC 640x480 YUV422 @30fps ~17.6 MB/s PAL 720x576 YUV422 @25fps ~19.7 MB/s isoc bandwidth. Now, due to limited alt settings in capture devices NTSC one ends up streaming with max_pkt_size=2688 and PAL with max_pkt_size=2892, both with interval=1. In terms of microframe time allocation this gives NTSC ~53us PAL ~57us and together ~110us > 100us == 80% of 125us uframe time. So those two devices can't work together simultaneously because the'd over allocate isochronous bandwidth. 80% seemed a bit arbitrary to me, and I've tried to raise it to 90% and both devices started to work together, so I though sometimes it would be a good idea for users to override hardcoded default of max 80% isoc bandwidth. After all, isn't it a user who should decide how to load the bus? If I can live with 10% or even 5% bulk bandwidth that should be ok. I'm a USB newcomer, but that 80% set in stone by USB 2.0 specification seems to be chosen pretty arbitrary to me, just to serve as a reasonable default. NOTE 1 ~~~~~~ for two streams with max_pkt_size=3072 (worst case) both time allocation would be 60us+60us=120us which is 96% periodic bandwidth leaving 4% for bulk and control. Alan Stern suggested that bulk then would be problematic (less than 300*8 bittimes left per microframe), but I think that is still enough for control traffic. NOTE 2 ~~~~~~ Sarah Sharp expressed concern that maxing out periodic bandwidth could lead to vendor-specific hardware bugs on host controllers, because > It's entirely possible that you'll run into > vendor-specific bugs if you try to pack the schedule with isochronous > transfers. I don't think any hardware designer would seriously test or > validate their hardware with a schedule that is basically a violation of > the USB bus spec (more than 80% for periodic transfers). So far I've only tested this patch on my HP Mini 5103 with N10 chipset kirr@mini:~$ lspci 00:00.0 Host bridge: Intel Corporation N10 Family DMI Bridge 00:02.0 VGA compatible controller: Intel Corporation N10 Family Integrated Graphics Controller 00:02.1 Display controller: Intel Corporation N10 Family Integrated Graphics Controller 00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 02) 00:1c.0 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 1 (rev 02) 00:1c.3 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 4 (rev 02) 00:1d.0 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #1 (rev 02) 00:1d.1 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #2 (rev 02) 00:1d.2 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #3 (rev 02) 00:1d.3 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #4 (rev 02) 00:1d.7 USB Controller: Intel Corporation N10/ICH 7 Family USB2 EHCI Controller (rev 02) 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev e2) 00:1f.0 ISA bridge: Intel Corporation NM10 Family LPC Controller (rev 02) 00:1f.2 SATA controller: Intel Corporation N10/ICH7 Family SATA AHCI Controller (rev 02) 01:00.0 Network controller: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller (rev 01) 02:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8059 PCI-E Gigabit Ethernet Controller (rev 11) and the system works stable with 110us/uframe (~88%) isoc bandwith allocated for above-mentioned isochronous transfers. NOTE 3 ~~~~~~ This feature is off by default. I mean max periodic bandwidth is set to 100us/uframe by default exactly as it was before the patch. So only those of us who need the extreme settings are taking the risk - normal users who do not alter uframe_periodic_max sysfs attribute should not see any change at all. NOTE 4 ~~~~~~ I've tried to update documentation in Documentation/ABI/ thoroughly, but only "TBD" was put into Documentation/usb/ehci.txt -- the text there seems to be outdated and much needing refreshing, before it could be amended. Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-07-03 23:36:57 +07:00
/* convert "usecs we need" to "max already claimed" */
usecs = ehci->uframe_periodic_max - usecs;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
for (uframe += frame << 3; uframe < EHCI_BANDWIDTH_SIZE;
uframe += uperiod) {
if (ehci->bandwidth[uframe] > usecs)
return 0;
}
// success!
return 1;
}
static int check_intr_schedule (
struct ehci_hcd *ehci,
unsigned frame,
unsigned uframe,
struct ehci_qh *qh,
unsigned *c_maskp,
struct ehci_tt *tt
)
{
int retval = -ENOSPC;
u8 mask = 0;
if (qh->ps.c_usecs && uframe >= 6) /* FSTN territory? */
goto done;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (!check_period(ehci, frame, uframe, qh->ps.bw_uperiod, qh->ps.usecs))
goto done;
if (!qh->ps.c_usecs) {
retval = 0;
*c_maskp = 0;
goto done;
}
#ifdef CONFIG_USB_EHCI_TT_NEWSCHED
if (tt_available(ehci, &qh->ps, tt, frame, uframe)) {
unsigned i;
/* TODO : this may need FSTN for SSPLIT in uframe 5. */
for (i = uframe+2; i < 8 && i <= uframe+4; i++)
if (!check_period(ehci, frame, i,
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
qh->ps.bw_uperiod, qh->ps.c_usecs))
goto done;
else
mask |= 1 << i;
retval = 0;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
*c_maskp = mask;
}
#else
/* Make sure this tt's buffer is also available for CSPLITs.
* We pessimize a bit; probably the typical full speed case
* doesn't need the second CSPLIT.
*
* NOTE: both SPLIT and CSPLIT could be checked in just
* one smart pass...
*/
mask = 0x03 << (uframe + qh->gap_uf);
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
*c_maskp = mask;
mask |= 1 << uframe;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (tt_no_collision(ehci, qh->ps.bw_period, qh->ps.udev, frame, mask)) {
if (!check_period(ehci, frame, uframe + qh->gap_uf + 1,
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
qh->ps.bw_uperiod, qh->ps.c_usecs))
goto done;
if (!check_period(ehci, frame, uframe + qh->gap_uf,
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
qh->ps.bw_uperiod, qh->ps.c_usecs))
goto done;
retval = 0;
}
#endif
done:
return retval;
}
/* "first fit" scheduling policy used the first time through,
* or when the previous schedule slot can't be re-used.
*/
static int qh_schedule(struct ehci_hcd *ehci, struct ehci_qh *qh)
{
int status = 0;
unsigned uframe;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
unsigned c_mask;
struct ehci_qh_hw *hw = qh->hw;
struct ehci_tt *tt;
hw->hw_next = EHCI_LIST_END(ehci);
/* reuse the previous schedule slots, if we can */
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (qh->ps.phase != NO_FRAME) {
ehci_dbg(ehci, "reused qh %p schedule\n", qh);
return 0;
}
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
uframe = 0;
c_mask = 0;
tt = find_tt(qh->ps.udev);
if (IS_ERR(tt)) {
status = PTR_ERR(tt);
goto done;
}
compute_tt_budget(ehci->tt_budget, tt);
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* else scan the schedule to find a group of slots such that all
* uframes have enough periodic bandwidth available.
*/
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* "normal" case, uframing flexible except with splits */
if (qh->ps.bw_period) {
int i;
unsigned frame;
for (i = qh->ps.bw_period; i > 0; --i) {
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
frame = ++ehci->random_frame & (qh->ps.bw_period - 1);
for (uframe = 0; uframe < 8; uframe++) {
status = check_intr_schedule(ehci,
frame, uframe, qh, &c_mask, tt);
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (status == 0)
goto got_it;
}
}
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* qh->ps.bw_period == 0 means every uframe */
} else {
status = check_intr_schedule(ehci, 0, 0, qh, &c_mask, tt);
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
}
if (status)
goto done;
got_it:
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
qh->ps.phase = (qh->ps.period ? ehci->random_frame &
(qh->ps.period - 1) : 0);
qh->ps.bw_phase = qh->ps.phase & (qh->ps.bw_period - 1);
qh->ps.phase_uf = uframe;
qh->ps.cs_mask = qh->ps.period ?
(c_mask << 8) | (1 << uframe) :
QH_SMASK;
/* reset S-frame and (maybe) C-frame masks */
hw->hw_info2 &= cpu_to_hc32(ehci, ~(QH_CMASK | QH_SMASK));
hw->hw_info2 |= cpu_to_hc32(ehci, qh->ps.cs_mask);
reserve_release_intr_bandwidth(ehci, qh, 1);
done:
return status;
}
static int intr_submit (
struct ehci_hcd *ehci,
struct urb *urb,
struct list_head *qtd_list,
gfp_t mem_flags
) {
unsigned epnum;
unsigned long flags;
struct ehci_qh *qh;
int status;
struct list_head empty;
/* get endpoint and transfer/schedule data */
epnum = urb->ep->desc.bEndpointAddress;
spin_lock_irqsave (&ehci->lock, flags);
if (unlikely(!HCD_HW_ACCESSIBLE(ehci_to_hcd(ehci)))) {
status = -ESHUTDOWN;
goto done_not_linked;
}
status = usb_hcd_link_urb_to_ep(ehci_to_hcd(ehci), urb);
if (unlikely(status))
goto done_not_linked;
/* get qh and force any scheduling errors */
INIT_LIST_HEAD (&empty);
qh = qh_append_tds(ehci, urb, &empty, epnum, &urb->ep->hcpriv);
if (qh == NULL) {
status = -ENOMEM;
goto done;
}
if (qh->qh_state == QH_STATE_IDLE) {
if ((status = qh_schedule (ehci, qh)) != 0)
goto done;
}
/* then queue the urb's tds to the qh */
qh = qh_append_tds(ehci, urb, qtd_list, epnum, &urb->ep->hcpriv);
BUG_ON (qh == NULL);
/* stuff into the periodic schedule */
if (qh->qh_state == QH_STATE_IDLE) {
qh_refresh(ehci, qh);
qh_link_periodic(ehci, qh);
} else {
/* cancel unlink wait for the qh */
cancel_unlink_wait_intr(ehci, qh);
}
/* ... update usbfs periodic stats */
ehci_to_hcd(ehci)->self.bandwidth_int_reqs++;
done:
if (unlikely(status))
usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
done_not_linked:
spin_unlock_irqrestore (&ehci->lock, flags);
if (status)
qtd_list_free (ehci, urb, qtd_list);
return status;
}
static void scan_intr(struct ehci_hcd *ehci)
{
struct ehci_qh *qh;
list_for_each_entry_safe(qh, ehci->qh_scan_next, &ehci->intr_qh_list,
intr_node) {
/* clean any finished work for this qh */
if (!list_empty(&qh->qtd_list)) {
int temp;
/*
* Unlinks could happen here; completion reporting
* drops the lock. That's why ehci->qh_scan_next
* always holds the next qh to scan; if the next qh
* gets unlinked then ehci->qh_scan_next is adjusted
* in qh_unlink_periodic().
*/
temp = qh_completions(ehci, qh);
if (unlikely(temp))
start_unlink_intr(ehci, qh);
else if (unlikely(list_empty(&qh->qtd_list) &&
qh->qh_state == QH_STATE_LINKED))
start_unlink_intr_wait(ehci, qh);
}
}
}
/*-------------------------------------------------------------------------*/
/* ehci_iso_stream ops work with both ITD and SITD */
static struct ehci_iso_stream *
iso_stream_alloc (gfp_t mem_flags)
{
struct ehci_iso_stream *stream;
stream = kzalloc(sizeof *stream, mem_flags);
if (likely (stream != NULL)) {
INIT_LIST_HEAD(&stream->td_list);
INIT_LIST_HEAD(&stream->free_list);
stream->next_uframe = NO_FRAME;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
stream->ps.phase = NO_FRAME;
}
return stream;
}
static void
iso_stream_init (
struct ehci_hcd *ehci,
struct ehci_iso_stream *stream,
struct urb *urb
)
{
static const u8 smask_out [] = { 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f };
struct usb_device *dev = urb->dev;
u32 buf1;
unsigned epnum, maxp;
int is_input;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
unsigned tmp;
/*
* this might be a "high bandwidth" highspeed endpoint,
* as encoded in the ep descriptor's wMaxPacket field
*/
epnum = usb_pipeendpoint(urb->pipe);
is_input = usb_pipein(urb->pipe) ? USB_DIR_IN : 0;
maxp = usb_endpoint_maxp(&urb->ep->desc);
if (is_input) {
buf1 = (1 << 11);
} else {
buf1 = 0;
}
/* knows about ITD vs SITD */
if (dev->speed == USB_SPEED_HIGH) {
unsigned multi = hb_mult(maxp);
stream->highspeed = 1;
maxp = max_packet(maxp);
buf1 |= maxp;
maxp *= multi;
stream->buf0 = cpu_to_hc32(ehci, (epnum << 8) | dev->devnum);
stream->buf1 = cpu_to_hc32(ehci, buf1);
stream->buf2 = cpu_to_hc32(ehci, multi);
/* usbfs wants to report the average usecs per frame tied up
* when transfers on this endpoint are scheduled ...
*/
stream->ps.usecs = HS_USECS_ISO(maxp);
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* period for bandwidth allocation */
tmp = min_t(unsigned, EHCI_BANDWIDTH_SIZE,
1 << (urb->ep->desc.bInterval - 1));
/* Allow urb->interval to override */
stream->ps.bw_uperiod = min_t(unsigned, tmp, urb->interval);
stream->uperiod = urb->interval;
stream->ps.period = urb->interval >> 3;
stream->bandwidth = stream->ps.usecs * 8 /
stream->ps.bw_uperiod;
} else {
u32 addr;
int think_time;
int hs_transfers;
addr = dev->ttport << 24;
if (!ehci_is_TDI(ehci)
|| (dev->tt->hub !=
ehci_to_hcd(ehci)->self.root_hub))
addr |= dev->tt->hub->devnum << 16;
addr |= epnum << 8;
addr |= dev->devnum;
stream->ps.usecs = HS_USECS_ISO(maxp);
think_time = dev->tt ? dev->tt->think_time : 0;
stream->ps.tt_usecs = NS_TO_US(think_time + usb_calc_bus_time(
dev->speed, is_input, 1, maxp));
hs_transfers = max (1u, (maxp + 187) / 188);
if (is_input) {
u32 tmp;
addr |= 1 << 31;
stream->ps.c_usecs = stream->ps.usecs;
stream->ps.usecs = HS_USECS_ISO(1);
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
stream->ps.cs_mask = 1;
/* c-mask as specified in USB 2.0 11.18.4 3.c */
tmp = (1 << (hs_transfers + 2)) - 1;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
stream->ps.cs_mask |= tmp << (8 + 2);
} else
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
stream->ps.cs_mask = smask_out[hs_transfers - 1];
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* period for bandwidth allocation */
tmp = min_t(unsigned, EHCI_BANDWIDTH_FRAMES,
1 << (urb->ep->desc.bInterval - 1));
/* Allow urb->interval to override */
stream->ps.bw_period = min_t(unsigned, tmp, urb->interval);
stream->ps.bw_uperiod = stream->ps.bw_period << 3;
stream->ps.period = urb->interval;
stream->uperiod = urb->interval << 3;
stream->bandwidth = (stream->ps.usecs + stream->ps.c_usecs) /
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
stream->ps.bw_period;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* stream->splits gets created from cs_mask later */
stream->address = cpu_to_hc32(ehci, addr);
}
stream->ps.udev = dev;
stream->ps.ep = urb->ep;
stream->bEndpointAddress = is_input | epnum;
stream->maxp = maxp;
}
static struct ehci_iso_stream *
iso_stream_find (struct ehci_hcd *ehci, struct urb *urb)
{
unsigned epnum;
struct ehci_iso_stream *stream;
struct usb_host_endpoint *ep;
unsigned long flags;
epnum = usb_pipeendpoint (urb->pipe);
if (usb_pipein(urb->pipe))
ep = urb->dev->ep_in[epnum];
else
ep = urb->dev->ep_out[epnum];
spin_lock_irqsave (&ehci->lock, flags);
stream = ep->hcpriv;
if (unlikely (stream == NULL)) {
stream = iso_stream_alloc(GFP_ATOMIC);
if (likely (stream != NULL)) {
ep->hcpriv = stream;
iso_stream_init(ehci, stream, urb);
}
/* if dev->ep [epnum] is a QH, hw is set */
} else if (unlikely (stream->hw != NULL)) {
ehci_dbg (ehci, "dev %s ep%d%s, not iso??\n",
urb->dev->devpath, epnum,
usb_pipein(urb->pipe) ? "in" : "out");
stream = NULL;
}
spin_unlock_irqrestore (&ehci->lock, flags);
return stream;
}
/*-------------------------------------------------------------------------*/
/* ehci_iso_sched ops can be ITD-only or SITD-only */
static struct ehci_iso_sched *
iso_sched_alloc (unsigned packets, gfp_t mem_flags)
{
struct ehci_iso_sched *iso_sched;
int size = sizeof *iso_sched;
size += packets * sizeof (struct ehci_iso_packet);
iso_sched = kzalloc(size, mem_flags);
if (likely (iso_sched != NULL)) {
INIT_LIST_HEAD (&iso_sched->td_list);
}
return iso_sched;
}
static inline void
itd_sched_init(
struct ehci_hcd *ehci,
struct ehci_iso_sched *iso_sched,
struct ehci_iso_stream *stream,
struct urb *urb
)
{
unsigned i;
dma_addr_t dma = urb->transfer_dma;
/* how many uframes are needed for these transfers */
iso_sched->span = urb->number_of_packets * stream->uperiod;
/* figure out per-uframe itd fields that we'll need later
* when we fit new itds into the schedule.
*/
for (i = 0; i < urb->number_of_packets; i++) {
struct ehci_iso_packet *uframe = &iso_sched->packet [i];
unsigned length;
dma_addr_t buf;
u32 trans;
length = urb->iso_frame_desc [i].length;
buf = dma + urb->iso_frame_desc [i].offset;
trans = EHCI_ISOC_ACTIVE;
trans |= buf & 0x0fff;
if (unlikely (((i + 1) == urb->number_of_packets))
&& !(urb->transfer_flags & URB_NO_INTERRUPT))
trans |= EHCI_ITD_IOC;
trans |= length << 16;
uframe->transaction = cpu_to_hc32(ehci, trans);
/* might need to cross a buffer page within a uframe */
uframe->bufp = (buf & ~(u64)0x0fff);
buf += length;
if (unlikely ((uframe->bufp != (buf & ~(u64)0x0fff))))
uframe->cross = 1;
}
}
static void
iso_sched_free (
struct ehci_iso_stream *stream,
struct ehci_iso_sched *iso_sched
)
{
if (!iso_sched)
return;
// caller must hold ehci->lock!
list_splice (&iso_sched->td_list, &stream->free_list);
kfree (iso_sched);
}
static int
itd_urb_transaction (
struct ehci_iso_stream *stream,
struct ehci_hcd *ehci,
struct urb *urb,
gfp_t mem_flags
)
{
struct ehci_itd *itd;
dma_addr_t itd_dma;
int i;
unsigned num_itds;
struct ehci_iso_sched *sched;
unsigned long flags;
sched = iso_sched_alloc (urb->number_of_packets, mem_flags);
if (unlikely (sched == NULL))
return -ENOMEM;
itd_sched_init(ehci, sched, stream, urb);
if (urb->interval < 8)
num_itds = 1 + (sched->span + 7) / 8;
else
num_itds = urb->number_of_packets;
/* allocate/init ITDs */
spin_lock_irqsave (&ehci->lock, flags);
for (i = 0; i < num_itds; i++) {
/*
* Use iTDs from the free list, but not iTDs that may
* still be in use by the hardware.
*/
if (likely(!list_empty(&stream->free_list))) {
itd = list_first_entry(&stream->free_list,
struct ehci_itd, itd_list);
if (itd->frame == ehci->now_frame)
goto alloc_itd;
list_del (&itd->itd_list);
itd_dma = itd->itd_dma;
} else {
alloc_itd:
spin_unlock_irqrestore (&ehci->lock, flags);
itd = dma_pool_alloc (ehci->itd_pool, mem_flags,
&itd_dma);
spin_lock_irqsave (&ehci->lock, flags);
if (!itd) {
iso_sched_free(stream, sched);
spin_unlock_irqrestore(&ehci->lock, flags);
return -ENOMEM;
}
}
memset (itd, 0, sizeof *itd);
itd->itd_dma = itd_dma;
itd->frame = NO_FRAME;
list_add (&itd->itd_list, &sched->td_list);
}
spin_unlock_irqrestore (&ehci->lock, flags);
/* temporarily store schedule info in hcpriv */
urb->hcpriv = sched;
urb->error_count = 0;
return 0;
}
/*-------------------------------------------------------------------------*/
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
static void reserve_release_iso_bandwidth(struct ehci_hcd *ehci,
struct ehci_iso_stream *stream, int sign)
{
unsigned uframe;
unsigned i, j;
unsigned s_mask, c_mask, m;
int usecs = stream->ps.usecs;
int c_usecs = stream->ps.c_usecs;
int tt_usecs = stream->ps.tt_usecs;
struct ehci_tt *tt;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (stream->ps.phase == NO_FRAME) /* Bandwidth wasn't reserved */
return;
uframe = stream->ps.bw_phase << 3;
bandwidth_dbg(ehci, sign, "iso", &stream->ps);
if (sign < 0) { /* Release bandwidth */
usecs = -usecs;
c_usecs = -c_usecs;
tt_usecs = -tt_usecs;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
}
if (!stream->splits) { /* High speed */
for (i = uframe + stream->ps.phase_uf; i < EHCI_BANDWIDTH_SIZE;
i += stream->ps.bw_uperiod)
ehci->bandwidth[i] += usecs;
} else { /* Full speed */
s_mask = stream->ps.cs_mask;
c_mask = s_mask >> 8;
/* NOTE: adjustment needed for frame overflow */
for (i = uframe; i < EHCI_BANDWIDTH_SIZE;
i += stream->ps.bw_uperiod) {
for ((j = stream->ps.phase_uf, m = 1 << j); j < 8;
(++j, m <<= 1)) {
if (s_mask & m)
ehci->bandwidth[i+j] += usecs;
else if (c_mask & m)
ehci->bandwidth[i+j] += c_usecs;
}
}
tt = find_tt(stream->ps.udev);
if (sign > 0)
list_add_tail(&stream->ps.ps_list, &tt->ps_list);
else
list_del(&stream->ps.ps_list);
for (i = uframe >> 3; i < EHCI_BANDWIDTH_FRAMES;
i += stream->ps.bw_period)
tt->bandwidth[i] += tt_usecs;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
}
}
static inline int
itd_slot_ok (
struct ehci_hcd *ehci,
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
struct ehci_iso_stream *stream,
unsigned uframe
)
{
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
unsigned usecs;
/* convert "usecs we need" to "max already claimed" */
usecs = ehci->uframe_periodic_max - stream->ps.usecs;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
for (uframe &= stream->ps.bw_uperiod - 1; uframe < EHCI_BANDWIDTH_SIZE;
uframe += stream->ps.bw_uperiod) {
if (ehci->bandwidth[uframe] > usecs)
return 0;
}
return 1;
}
static inline int
sitd_slot_ok (
struct ehci_hcd *ehci,
struct ehci_iso_stream *stream,
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
unsigned uframe,
struct ehci_iso_sched *sched,
struct ehci_tt *tt
)
{
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
unsigned mask, tmp;
unsigned frame, uf;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
mask = stream->ps.cs_mask << (uframe & 7);
/* for OUT, don't wrap SSPLIT into H-microframe 7 */
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (((stream->ps.cs_mask & 0xff) << (uframe & 7)) >= (1 << 7))
return 0;
/* for IN, don't wrap CSPLIT into the next frame */
if (mask & ~0xffff)
return 0;
/* check bandwidth */
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
uframe &= stream->ps.bw_uperiod - 1;
frame = uframe >> 3;
#ifdef CONFIG_USB_EHCI_TT_NEWSCHED
/* The tt's fullspeed bus bandwidth must be available.
* tt_available scheduling guarantees 10+% for control/bulk.
*/
uf = uframe & 7;
if (!tt_available(ehci, &stream->ps, tt, frame, uf))
return 0;
#else
/* tt must be idle for start(s), any gap, and csplit.
* assume scheduling slop leaves 10+% for control/bulk.
*/
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (!tt_no_collision(ehci, stream->ps.bw_period,
stream->ps.udev, frame, mask))
return 0;
#endif
do {
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
unsigned max_used;
unsigned i;
/* check starts (OUT uses more than one) */
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
uf = uframe;
max_used = ehci->uframe_periodic_max - stream->ps.usecs;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
for (tmp = stream->ps.cs_mask & 0xff; tmp; tmp >>= 1, uf++) {
if (ehci->bandwidth[uf] > max_used)
return 0;
}
/* for IN, check CSPLIT */
if (stream->ps.c_usecs) {
max_used = ehci->uframe_periodic_max -
stream->ps.c_usecs;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
uf = uframe & ~7;
tmp = 1 << (2+8);
for (i = (uframe & 7) + 2; i < 8; (++i, tmp <<= 1)) {
if ((stream->ps.cs_mask & tmp) == 0)
continue;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (ehci->bandwidth[uf+i] > max_used)
return 0;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
}
}
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
uframe += stream->ps.bw_uperiod;
} while (uframe < EHCI_BANDWIDTH_SIZE);
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
stream->ps.cs_mask <<= uframe & 7;
stream->splits = cpu_to_hc32(ehci, stream->ps.cs_mask);
return 1;
}
/*
* This scheduler plans almost as far into the future as it has actual
* periodic schedule slots. (Affected by TUNE_FLS, which defaults to
* "as small as possible" to be cache-friendlier.) That limits the size
* transfers you can stream reliably; avoid more than 64 msec per urb.
* Also avoid queue depths of less than ehci's worst irq latency (affected
* by the per-urb URB_NO_INTERRUPT hint, the log2_irq_thresh module parameter,
* and other factors); or more than about 230 msec total (for portability,
* given EHCI_TUNE_FLS and the slop). Or, write a smarter scheduler!
*/
static int
iso_stream_schedule (
struct ehci_hcd *ehci,
struct urb *urb,
struct ehci_iso_stream *stream
)
{
u32 now, base, next, start, period, span, now2;
u32 wrap = 0, skip = 0;
int status = 0;
unsigned mod = ehci->periodic_size << 3;
struct ehci_iso_sched *sched = urb->hcpriv;
bool empty = list_empty(&stream->td_list);
bool new_stream = false;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
period = stream->uperiod;
span = sched->span;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
if (!stream->highspeed)
span <<= 3;
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* Start a new isochronous stream? */
if (unlikely(empty && !hcd_periodic_completion_in_progress(
ehci_to_hcd(ehci), urb->ep))) {
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* Schedule the endpoint */
if (stream->ps.phase == NO_FRAME) {
int done = 0;
struct ehci_tt *tt = find_tt(stream->ps.udev);
if (IS_ERR(tt)) {
status = PTR_ERR(tt);
goto fail;
}
compute_tt_budget(ehci->tt_budget, tt);
start = ((-(++ehci->random_frame)) << 3) & (period - 1);
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* find a uframe slot with enough bandwidth.
* Early uframes are more precious because full-speed
* iso IN transfers can't use late uframes,
* and therefore they should be allocated last.
*/
next = start;
start += period;
do {
start--;
/* check schedule: enough space? */
if (stream->highspeed) {
if (itd_slot_ok(ehci, stream, start))
done = 1;
} else {
if ((start % 8) >= 6)
continue;
if (sitd_slot_ok(ehci, stream, start,
sched, tt))
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
done = 1;
}
} while (start > next && !done);
/* no room in the schedule */
if (!done) {
ehci_dbg(ehci, "iso sched full %p", urb);
status = -ENOSPC;
goto fail;
}
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
stream->ps.phase = (start >> 3) &
(stream->ps.period - 1);
stream->ps.bw_phase = stream->ps.phase &
(stream->ps.bw_period - 1);
stream->ps.phase_uf = start & 7;
reserve_release_iso_bandwidth(ehci, stream, 1);
}
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
/* New stream is already scheduled; use the upcoming slot */
else {
start = (stream->ps.phase << 3) + stream->ps.phase_uf;
}
stream->next_uframe = start;
new_stream = true;
}
now = ehci_read_frame_index(ehci) & (mod - 1);
/* Take the isochronous scheduling threshold into account */
if (ehci->i_thresh)
next = now + ehci->i_thresh; /* uframe cache */
else
next = (now + 2 + 7) & ~0x07; /* full frame cache */
/* If needed, initialize last_iso_frame so that this URB will be seen */
if (ehci->isoc_count == 0)
ehci->last_iso_frame = now >> 3;
/*
* Use ehci->last_iso_frame as the base. There can't be any
* TDs scheduled for earlier than that.
*/
base = ehci->last_iso_frame << 3;
next = (next - base) & (mod - 1);
start = (stream->next_uframe - base) & (mod - 1);
if (unlikely(new_stream))
goto do_ASAP;
/*
USB: EHCI: use a bandwidth-allocation table This patch significantly changes the scheduling code in ehci-hcd. Instead of calculating the current bandwidth utilization by trudging through the schedule and adding up the times used by the existing transfers, we will now maintain a table holding the time used for each of 64 microframes. This will drastically speed up the bandwidth computations. In addition, it eliminates a theoretical bug. An isochronous endpoint may have bandwidth reserved even at times when it has no transfers listed in the schedule. The table will keep track of the reserved bandwidth, whereas adding up entries in the schedule would miss it. As a corollary, we can keep bandwidth reserved for endpoints even when they aren't in active use. Eventually the bandwidth will be reserved when a new alternate setting is installed; for now the endpoint's reservation takes place when its first URB is submitted. A drawback of this approach is that transfers with an interval larger than 64 microframes will have to be charged for bandwidth as though the interval was 64. In practice this shouldn't matter much; transfers with longer intervals tend to be rather short anyway (things like hubs or HID devices). Another minor drawback is that we will keep track of two different period and phase values: the actual ones and the ones used for bandwidth allocation (which are limited to 64). This adds only a small amount of overhead: 3 bytes for each endpoint. The patch also adds a new debugfs file named "bandwidth" to display the information stored in the new table. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 22:29:13 +07:00
* Typical case: reuse current schedule, stream may still be active.
* Hopefully there are no gaps from the host falling behind
* (irq delays etc). If there are, the behavior depends on
* whether URB_ISO_ASAP is set.
*/
now2 = (now - base) & (mod - 1);
USB: ehci: Respect IST when scheduling new split iTDs. The EHCI specification says that an EHCI host controller may cache part of the isochronous schedule. The EHCI controller must advertise how much it caches in the schedule through the HCCPARAMS register isochronous scheduling threshold (IST) bits. In theory, adding new iTDs within the IST should be harmless. The HW will follow the old cached linked list and miss the new iTD. SW will notice HW missed the iTD and return 0 for the transfer length. However, Intel ICH9 chipsets (and some later chipsets) have issues when SW attempts to schedule a split transaction within the IST. All transfers will cease being sent out that port, and the drivers will see isochronous packets complete with a length of zero. Start of frames may or may not also disappear, causing the device to go into auto-suspend. This "bus stall" will continue until a control or bulk transfer is queued to a device under that roothub. Most drivers will never cause this behavior, because they use multiple URBs with multiple packets to keep the bus busy. If you limit the number of URBs to one, you may be able to hit this bug. Make sure the EHCI driver does not schedule full-speed transfers within the IST under an Intel chipset. Make sure that when we fall behind the current microframe plus IST, we schedule the new transfer at the next periodic interval after the IST. Don't change the scheduling for new transfers, since the schedule slop will always be greater than the IST. Allow high speed isochronous transfers to be scheduled within the IST, since this doesn't trigger the Intel chipset bug. Make sure that if the host caches the full frame, the EHCI driver's internal isochronous threshold (ehci->i_thresh) is set to 8 microframes + 2 microframes wiggle room. This is similar to what is done in the case where the host caches less than the full frame. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-28 00:55:05 +07:00
/* Is the schedule about to wrap around? */
if (unlikely(!empty && start < period)) {
ehci_dbg(ehci, "request %p would overflow (%u-%u < %u mod %u)\n",
urb, stream->next_uframe, base, period, mod);
status = -EFBIG;
goto fail;
}
/* Is the next packet scheduled after the base time? */
if (likely(!empty || start <= now2 + period)) {
EHCI: improved logic for isochronous scheduling This patch (as1608) reworks the logic used by ehci-hcd for scheduling isochronous transfers. Now the modular calculations are all based on a window that starts at the last frame scanned for isochronous completions. No transfer descriptors for any earlier frames can possibly remain on the schedule, so there can be no confusion from schedule wrap-around. This removes the need for a "slop" region of arbitrary size. There's no need to check for URBs that are longer than the schedule length. With the old code they could throw things off by wrapping around and appearing to end in the near future rather than the distant future. Now such confusion isn't possible, and the existing test for submissions that extend too far into the future will also catch those that exceed the schedule length. (But there still has to be an initial test to handle the case where the schedule already extends as far into the future as possible.) Delays caused by IRQ latency won't confuse the algorithm unless they are ridiculously long (over 250 ms); they will merely reduce how far into the future new transfers can be scheduled. A few people have reported problems caused by delays of 50 ms or so. Now instead of failing completely, isochronous transfers will experience a brief glitch and then continue normally. (Whether this is truly a good thing is debatable. A latency as large as 50 ms generally indicates a bug is present, and complete failure of audio or video transfers draws people's attention pretty vividly. Making the transfers more robust also makes it easier for such bugs to remain undetected.) Finally, ehci->next_frame is renamed to ehci->last_iso_frame, because that better describes what it is: the last frame to have been scanned for isochronous completions. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-29 03:01:23 +07:00
/* URB_ISO_ASAP: make sure that start >= next */
if (unlikely(start < next &&
(urb->transfer_flags & URB_ISO_ASAP)))
goto do_ASAP;
/* Otherwise use start, if it's not in the past */
if (likely(start >= now2))
goto use_start;
/* Otherwise we got an underrun while the queue was empty */
} else {
if (urb->transfer_flags & URB_ISO_ASAP)
goto do_ASAP;
wrap = mod;
now2 += mod;
}
EHCI: improved logic for isochronous scheduling This patch (as1608) reworks the logic used by ehci-hcd for scheduling isochronous transfers. Now the modular calculations are all based on a window that starts at the last frame scanned for isochronous completions. No transfer descriptors for any earlier frames can possibly remain on the schedule, so there can be no confusion from schedule wrap-around. This removes the need for a "slop" region of arbitrary size. There's no need to check for URBs that are longer than the schedule length. With the old code they could throw things off by wrapping around and appearing to end in the near future rather than the distant future. Now such confusion isn't possible, and the existing test for submissions that extend too far into the future will also catch those that exceed the schedule length. (But there still has to be an initial test to handle the case where the schedule already extends as far into the future as possible.) Delays caused by IRQ latency won't confuse the algorithm unless they are ridiculously long (over 250 ms); they will merely reduce how far into the future new transfers can be scheduled. A few people have reported problems caused by delays of 50 ms or so. Now instead of failing completely, isochronous transfers will experience a brief glitch and then continue normally. (Whether this is truly a good thing is debatable. A latency as large as 50 ms generally indicates a bug is present, and complete failure of audio or video transfers draws people's attention pretty vividly. Making the transfers more robust also makes it easier for such bugs to remain undetected.) Finally, ehci->next_frame is renamed to ehci->last_iso_frame, because that better describes what it is: the last frame to have been scanned for isochronous completions. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-29 03:01:23 +07:00
/* How many uframes and packets do we need to skip? */
skip = (now2 - start + period - 1) & -period;
if (skip >= span) { /* Entirely in the past? */
ehci_dbg(ehci, "iso underrun %p (%u+%u < %u) [%u]\n",
urb, start + base, span - period, now2 + base,
base);
/* Try to keep the last TD intact for scanning later */
skip = span - period;
/* Will it come before the current scan position? */
if (empty) {
skip = span; /* Skip the entire URB */
status = 1; /* and give it back immediately */
iso_sched_free(stream, sched);
sched = NULL;
}
}
urb->error_count = skip / period;
if (sched)
sched->first_packet = urb->error_count;
goto use_start;
do_ASAP:
/* Use the first slot after "next" */
start = next + ((start - next) & (period - 1));
use_start:
/* Tried to schedule too far into the future? */
if (unlikely(start + span - period >= mod + wrap)) {
EHCI: improved logic for isochronous scheduling This patch (as1608) reworks the logic used by ehci-hcd for scheduling isochronous transfers. Now the modular calculations are all based on a window that starts at the last frame scanned for isochronous completions. No transfer descriptors for any earlier frames can possibly remain on the schedule, so there can be no confusion from schedule wrap-around. This removes the need for a "slop" region of arbitrary size. There's no need to check for URBs that are longer than the schedule length. With the old code they could throw things off by wrapping around and appearing to end in the near future rather than the distant future. Now such confusion isn't possible, and the existing test for submissions that extend too far into the future will also catch those that exceed the schedule length. (But there still has to be an initial test to handle the case where the schedule already extends as far into the future as possible.) Delays caused by IRQ latency won't confuse the algorithm unless they are ridiculously long (over 250 ms); they will merely reduce how far into the future new transfers can be scheduled. A few people have reported problems caused by delays of 50 ms or so. Now instead of failing completely, isochronous transfers will experience a brief glitch and then continue normally. (Whether this is truly a good thing is debatable. A latency as large as 50 ms generally indicates a bug is present, and complete failure of audio or video transfers draws people's attention pretty vividly. Making the transfers more robust also makes it easier for such bugs to remain undetected.) Finally, ehci->next_frame is renamed to ehci->last_iso_frame, because that better describes what it is: the last frame to have been scanned for isochronous completions. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-29 03:01:23 +07:00
ehci_dbg(ehci, "request %p would overflow (%u+%u >= %u)\n",
urb, start, span - period, mod + wrap);
status = -EFBIG;
goto fail;
}
start += base;
stream->next_uframe = (start + skip) & (mod - 1);
/* report high speed start in uframes; full speed, in frames */
urb->start_frame = start & (mod - 1);
if (!stream->highspeed)
urb->start_frame >>= 3;
return status;
fail:
iso_sched_free(stream, sched);
urb->hcpriv = NULL;
return status;
}
/*-------------------------------------------------------------------------*/
static inline void
itd_init(struct ehci_hcd *ehci, struct ehci_iso_stream *stream,
struct ehci_itd *itd)
{
int i;
/* it's been recently zeroed */
itd->hw_next = EHCI_LIST_END(ehci);
itd->hw_bufp [0] = stream->buf0;
itd->hw_bufp [1] = stream->buf1;
itd->hw_bufp [2] = stream->buf2;
for (i = 0; i < 8; i++)
itd->index[i] = -1;
/* All other fields are filled when scheduling */
}
static inline void
itd_patch(
struct ehci_hcd *ehci,
struct ehci_itd *itd,
struct ehci_iso_sched *iso_sched,
unsigned index,
u16 uframe
)
{
struct ehci_iso_packet *uf = &iso_sched->packet [index];
unsigned pg = itd->pg;
// BUG_ON (pg == 6 && uf->cross);
uframe &= 0x07;
itd->index [uframe] = index;
itd->hw_transaction[uframe] = uf->transaction;
itd->hw_transaction[uframe] |= cpu_to_hc32(ehci, pg << 12);
itd->hw_bufp[pg] |= cpu_to_hc32(ehci, uf->bufp & ~(u32)0);
itd->hw_bufp_hi[pg] |= cpu_to_hc32(ehci, (u32)(uf->bufp >> 32));
/* iso_frame_desc[].offset must be strictly increasing */
if (unlikely (uf->cross)) {
u64 bufp = uf->bufp + 4096;
itd->pg = ++pg;
itd->hw_bufp[pg] |= cpu_to_hc32(ehci, bufp & ~(u32)0);
itd->hw_bufp_hi[pg] |= cpu_to_hc32(ehci, (u32)(bufp >> 32));
}
}
static inline void
itd_link (struct ehci_hcd *ehci, unsigned frame, struct ehci_itd *itd)
{
union ehci_shadow *prev = &ehci->pshadow[frame];
__hc32 *hw_p = &ehci->periodic[frame];
union ehci_shadow here = *prev;
__hc32 type = 0;
/* skip any iso nodes which might belong to previous microframes */
while (here.ptr) {
type = Q_NEXT_TYPE(ehci, *hw_p);
if (type == cpu_to_hc32(ehci, Q_TYPE_QH))
break;
prev = periodic_next_shadow(ehci, prev, type);
hw_p = shadow_next_periodic(ehci, &here, type);
here = *prev;
}
itd->itd_next = here;
itd->hw_next = *hw_p;
prev->itd = itd;
itd->frame = frame;
wmb ();
*hw_p = cpu_to_hc32(ehci, itd->itd_dma | Q_TYPE_ITD);
}
/* fit urb's itds into the selected schedule slot; activate as needed */
static void itd_link_urb(
struct ehci_hcd *ehci,
struct urb *urb,
unsigned mod,
struct ehci_iso_stream *stream
)
{
int packet;
unsigned next_uframe, uframe, frame;
struct ehci_iso_sched *iso_sched = urb->hcpriv;
struct ehci_itd *itd;
next_uframe = stream->next_uframe & (mod - 1);
if (unlikely (list_empty(&stream->td_list)))
ehci_to_hcd(ehci)->self.bandwidth_allocated
+= stream->bandwidth;
if (ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs == 0) {
USB host: Move AMD PLL quirk to pci-quirks.c This patch moves the AMD PLL quirk code in OHCI/EHCI driver to pci-quirks.c, and exports the functions to be used by xHCI driver later. AMD PLL quirk disable the optional PM feature inside specific SB700/SB800/Hudson-2/3 platforms under the following conditions: 1. If an isochronous device is connected to OHCI/EHCI/xHCI port and is active; 2. Optional PM feature that powers down the internal Bus PLL when the link is in low power state is enabled. Without AMD PLL quirk, USB isochronous stream may stutter or have breaks occasionally, which greatly impair the performance of audio/video streams. Currently AMD PLL quirk is implemented in OHCI and EHCI driver, and will be added to xHCI driver too. They are doing similar things actually, so move the quirk code to pci-quirks.c, which has several advantages: 1. Remove duplicate defines and functions in OHCI/EHCI (and xHCI) driver and make them cleaner; 2. AMD chipset information will be probed only once and then stored. Currently they're probed during every OHCI/EHCI initialization, move the detect code to pci-quirks.c saves the repeat detect cost; 3. Build up synchronization among OHCI/EHCI/xHCI driver. In current code, every host controller enable/disable PLL only according to its own status, and may enable PLL while there is still isoc transfer on other HCs. Move the quirk to pci-quirks.c prevents this issue. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Alex He <alex.he@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-01 13:57:05 +07:00
if (ehci->amd_pll_fix == 1)
usb_amd_quirk_pll_disable();
}
ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs++;
/* fill iTDs uframe by uframe */
for (packet = iso_sched->first_packet, itd = NULL;
packet < urb->number_of_packets;) {
if (itd == NULL) {
/* ASSERT: we have all necessary itds */
// BUG_ON (list_empty (&iso_sched->td_list));
/* ASSERT: no itds for this endpoint in this uframe */
itd = list_entry (iso_sched->td_list.next,
struct ehci_itd, itd_list);
list_move_tail (&itd->itd_list, &stream->td_list);
itd->stream = stream;
itd->urb = urb;
itd_init (ehci, stream, itd);
}
uframe = next_uframe & 0x07;
frame = next_uframe >> 3;
itd_patch(ehci, itd, iso_sched, packet, uframe);
next_uframe += stream->uperiod;
next_uframe &= mod - 1;
packet++;
/* link completed itds into the schedule */
if (((next_uframe >> 3) != frame)
|| packet == urb->number_of_packets) {
itd_link(ehci, frame & (ehci->periodic_size - 1), itd);
itd = NULL;
}
}
stream->next_uframe = next_uframe;
/* don't need that schedule data any more */
iso_sched_free (stream, iso_sched);
urb->hcpriv = stream;
++ehci->isoc_count;
enable_periodic(ehci);
}
#define ISO_ERRS (EHCI_ISOC_BUF_ERR | EHCI_ISOC_BABBLE | EHCI_ISOC_XACTERR)
/* Process and recycle a completed ITD. Return true iff its urb completed,
* and hence its completion callback probably added things to the hardware
* schedule.
*
* Note that we carefully avoid recycling this descriptor until after any
* completion callback runs, so that it won't be reused quickly. That is,
* assuming (a) no more than two urbs per frame on this endpoint, and also
* (b) only this endpoint's completions submit URBs. It seems some silicon
* corrupts things if you reuse completed descriptors very quickly...
*/
static bool itd_complete(struct ehci_hcd *ehci, struct ehci_itd *itd)
{
struct urb *urb = itd->urb;
struct usb_iso_packet_descriptor *desc;
u32 t;
unsigned uframe;
int urb_index = -1;
struct ehci_iso_stream *stream = itd->stream;
struct usb_device *dev;
bool retval = false;
/* for each uframe with a packet */
for (uframe = 0; uframe < 8; uframe++) {
if (likely (itd->index[uframe] == -1))
continue;
urb_index = itd->index[uframe];
desc = &urb->iso_frame_desc [urb_index];
t = hc32_to_cpup(ehci, &itd->hw_transaction [uframe]);
itd->hw_transaction [uframe] = 0;
/* report transfer status */
if (unlikely (t & ISO_ERRS)) {
urb->error_count++;
if (t & EHCI_ISOC_BUF_ERR)
desc->status = usb_pipein (urb->pipe)
? -ENOSR /* hc couldn't read */
: -ECOMM; /* hc couldn't write */
else if (t & EHCI_ISOC_BABBLE)
desc->status = -EOVERFLOW;
else /* (t & EHCI_ISOC_XACTERR) */
desc->status = -EPROTO;
/* HC need not update length with this error */
if (!(t & EHCI_ISOC_BABBLE)) {
desc->actual_length = EHCI_ITD_LENGTH(t);
urb->actual_length += desc->actual_length;
}
} else if (likely ((t & EHCI_ISOC_ACTIVE) == 0)) {
desc->status = 0;
desc->actual_length = EHCI_ITD_LENGTH(t);
urb->actual_length += desc->actual_length;
} else {
/* URB was too late */
urb->error_count++;
}
}
/* handle completion now? */
if (likely ((urb_index + 1) != urb->number_of_packets))
goto done;
/* ASSERT: it's really the last itd for this urb
list_for_each_entry (itd, &stream->td_list, itd_list)
BUG_ON (itd->urb == urb);
*/
/* give urb back to the driver; completion often (re)submits */
dev = urb->dev;
ehci_urb_done(ehci, urb, 0);
retval = true;
urb = NULL;
--ehci->isoc_count;
disable_periodic(ehci);
ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--;
if (ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs == 0) {
USB host: Move AMD PLL quirk to pci-quirks.c This patch moves the AMD PLL quirk code in OHCI/EHCI driver to pci-quirks.c, and exports the functions to be used by xHCI driver later. AMD PLL quirk disable the optional PM feature inside specific SB700/SB800/Hudson-2/3 platforms under the following conditions: 1. If an isochronous device is connected to OHCI/EHCI/xHCI port and is active; 2. Optional PM feature that powers down the internal Bus PLL when the link is in low power state is enabled. Without AMD PLL quirk, USB isochronous stream may stutter or have breaks occasionally, which greatly impair the performance of audio/video streams. Currently AMD PLL quirk is implemented in OHCI and EHCI driver, and will be added to xHCI driver too. They are doing similar things actually, so move the quirk code to pci-quirks.c, which has several advantages: 1. Remove duplicate defines and functions in OHCI/EHCI (and xHCI) driver and make them cleaner; 2. AMD chipset information will be probed only once and then stored. Currently they're probed during every OHCI/EHCI initialization, move the detect code to pci-quirks.c saves the repeat detect cost; 3. Build up synchronization among OHCI/EHCI/xHCI driver. In current code, every host controller enable/disable PLL only according to its own status, and may enable PLL while there is still isoc transfer on other HCs. Move the quirk to pci-quirks.c prevents this issue. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Alex He <alex.he@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-01 13:57:05 +07:00
if (ehci->amd_pll_fix == 1)
usb_amd_quirk_pll_enable();
}
if (unlikely(list_is_singular(&stream->td_list)))
ehci_to_hcd(ehci)->self.bandwidth_allocated
-= stream->bandwidth;
done:
itd->urb = NULL;
/* Add to the end of the free list for later reuse */
list_move_tail(&itd->itd_list, &stream->free_list);
/* Recycle the iTDs when the pipeline is empty (ep no longer in use) */
if (list_empty(&stream->td_list)) {
list_splice_tail_init(&stream->free_list,
&ehci->cached_itd_list);
start_free_itds(ehci);
}
return retval;
}
/*-------------------------------------------------------------------------*/
static int itd_submit (struct ehci_hcd *ehci, struct urb *urb,
gfp_t mem_flags)
{
int status = -EINVAL;
unsigned long flags;
struct ehci_iso_stream *stream;
/* Get iso_stream head */
stream = iso_stream_find (ehci, urb);
if (unlikely (stream == NULL)) {
ehci_dbg (ehci, "can't get iso stream\n");
return -ENOMEM;
}
if (unlikely(urb->interval != stream->uperiod)) {
ehci_dbg (ehci, "can't change iso interval %d --> %d\n",
stream->uperiod, urb->interval);
goto done;
}
#ifdef EHCI_URB_TRACE
ehci_dbg (ehci,
"%s %s urb %p ep%d%s len %d, %d pkts %d uframes [%p]\n",
__func__, urb->dev->devpath, urb,
usb_pipeendpoint (urb->pipe),
usb_pipein (urb->pipe) ? "in" : "out",
urb->transfer_buffer_length,
urb->number_of_packets, urb->interval,
stream);
#endif
/* allocate ITDs w/o locking anything */
status = itd_urb_transaction (stream, ehci, urb, mem_flags);
if (unlikely (status < 0)) {
ehci_dbg (ehci, "can't init itds\n");
goto done;
}
/* schedule ... need to lock */
spin_lock_irqsave (&ehci->lock, flags);
if (unlikely(!HCD_HW_ACCESSIBLE(ehci_to_hcd(ehci)))) {
status = -ESHUTDOWN;
goto done_not_linked;
}
status = usb_hcd_link_urb_to_ep(ehci_to_hcd(ehci), urb);
if (unlikely(status))
goto done_not_linked;
status = iso_stream_schedule(ehci, urb, stream);
if (likely(status == 0)) {
itd_link_urb (ehci, urb, ehci->periodic_size << 3, stream);
} else if (status > 0) {
status = 0;
ehci_urb_done(ehci, urb, 0);
} else {
usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
}
done_not_linked:
spin_unlock_irqrestore (&ehci->lock, flags);
done:
return status;
}
/*-------------------------------------------------------------------------*/
/*
* "Split ISO TDs" ... used for USB 1.1 devices going through the
* TTs in USB 2.0 hubs. These need microframe scheduling.
*/
static inline void
sitd_sched_init(
struct ehci_hcd *ehci,
struct ehci_iso_sched *iso_sched,
struct ehci_iso_stream *stream,
struct urb *urb
)
{
unsigned i;
dma_addr_t dma = urb->transfer_dma;
/* how many frames are needed for these transfers */
iso_sched->span = urb->number_of_packets * stream->ps.period;
/* figure out per-frame sitd fields that we'll need later
* when we fit new sitds into the schedule.
*/
for (i = 0; i < urb->number_of_packets; i++) {
struct ehci_iso_packet *packet = &iso_sched->packet [i];
unsigned length;
dma_addr_t buf;
u32 trans;
length = urb->iso_frame_desc [i].length & 0x03ff;
buf = dma + urb->iso_frame_desc [i].offset;
trans = SITD_STS_ACTIVE;
if (((i + 1) == urb->number_of_packets)
&& !(urb->transfer_flags & URB_NO_INTERRUPT))
trans |= SITD_IOC;
trans |= length << 16;
packet->transaction = cpu_to_hc32(ehci, trans);
/* might need to cross a buffer page within a td */
packet->bufp = buf;
packet->buf1 = (buf + length) & ~0x0fff;
if (packet->buf1 != (buf & ~(u64)0x0fff))
packet->cross = 1;
/* OUT uses multiple start-splits */
if (stream->bEndpointAddress & USB_DIR_IN)
continue;
length = (length + 187) / 188;
if (length > 1) /* BEGIN vs ALL */
length |= 1 << 3;
packet->buf1 |= length;
}
}
static int
sitd_urb_transaction (
struct ehci_iso_stream *stream,
struct ehci_hcd *ehci,
struct urb *urb,
gfp_t mem_flags
)
{
struct ehci_sitd *sitd;
dma_addr_t sitd_dma;
int i;
struct ehci_iso_sched *iso_sched;
unsigned long flags;
iso_sched = iso_sched_alloc (urb->number_of_packets, mem_flags);
if (iso_sched == NULL)
return -ENOMEM;
sitd_sched_init(ehci, iso_sched, stream, urb);
/* allocate/init sITDs */
spin_lock_irqsave (&ehci->lock, flags);
for (i = 0; i < urb->number_of_packets; i++) {
/* NOTE: for now, we don't try to handle wraparound cases
* for IN (using sitd->hw_backpointer, like a FSTN), which
* means we never need two sitds for full speed packets.
*/
/*
* Use siTDs from the free list, but not siTDs that may
* still be in use by the hardware.
*/
if (likely(!list_empty(&stream->free_list))) {
sitd = list_first_entry(&stream->free_list,
struct ehci_sitd, sitd_list);
if (sitd->frame == ehci->now_frame)
goto alloc_sitd;
list_del (&sitd->sitd_list);
sitd_dma = sitd->sitd_dma;
} else {
alloc_sitd:
spin_unlock_irqrestore (&ehci->lock, flags);
sitd = dma_pool_alloc (ehci->sitd_pool, mem_flags,
&sitd_dma);
spin_lock_irqsave (&ehci->lock, flags);
if (!sitd) {
iso_sched_free(stream, iso_sched);
spin_unlock_irqrestore(&ehci->lock, flags);
return -ENOMEM;
}
}
memset (sitd, 0, sizeof *sitd);
sitd->sitd_dma = sitd_dma;
sitd->frame = NO_FRAME;
list_add (&sitd->sitd_list, &iso_sched->td_list);
}
/* temporarily store schedule info in hcpriv */
urb->hcpriv = iso_sched;
urb->error_count = 0;
spin_unlock_irqrestore (&ehci->lock, flags);
return 0;
}
/*-------------------------------------------------------------------------*/
static inline void
sitd_patch(
struct ehci_hcd *ehci,
struct ehci_iso_stream *stream,
struct ehci_sitd *sitd,
struct ehci_iso_sched *iso_sched,
unsigned index
)
{
struct ehci_iso_packet *uf = &iso_sched->packet [index];
u64 bufp = uf->bufp;
sitd->hw_next = EHCI_LIST_END(ehci);
sitd->hw_fullspeed_ep = stream->address;
sitd->hw_uframe = stream->splits;
sitd->hw_results = uf->transaction;
sitd->hw_backpointer = EHCI_LIST_END(ehci);
bufp = uf->bufp;
sitd->hw_buf[0] = cpu_to_hc32(ehci, bufp);
sitd->hw_buf_hi[0] = cpu_to_hc32(ehci, bufp >> 32);
sitd->hw_buf[1] = cpu_to_hc32(ehci, uf->buf1);
if (uf->cross)
bufp += 4096;
sitd->hw_buf_hi[1] = cpu_to_hc32(ehci, bufp >> 32);
sitd->index = index;
}
static inline void
sitd_link (struct ehci_hcd *ehci, unsigned frame, struct ehci_sitd *sitd)
{
/* note: sitd ordering could matter (CSPLIT then SSPLIT) */
sitd->sitd_next = ehci->pshadow [frame];
sitd->hw_next = ehci->periodic [frame];
ehci->pshadow [frame].sitd = sitd;
sitd->frame = frame;
wmb ();
ehci->periodic[frame] = cpu_to_hc32(ehci, sitd->sitd_dma | Q_TYPE_SITD);
}
/* fit urb's sitds into the selected schedule slot; activate as needed */
static void sitd_link_urb(
struct ehci_hcd *ehci,
struct urb *urb,
unsigned mod,
struct ehci_iso_stream *stream
)
{
int packet;
unsigned next_uframe;
struct ehci_iso_sched *sched = urb->hcpriv;
struct ehci_sitd *sitd;
next_uframe = stream->next_uframe;
if (list_empty(&stream->td_list))
/* usbfs ignores TT bandwidth */
ehci_to_hcd(ehci)->self.bandwidth_allocated
+= stream->bandwidth;
if (ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs == 0) {
USB host: Move AMD PLL quirk to pci-quirks.c This patch moves the AMD PLL quirk code in OHCI/EHCI driver to pci-quirks.c, and exports the functions to be used by xHCI driver later. AMD PLL quirk disable the optional PM feature inside specific SB700/SB800/Hudson-2/3 platforms under the following conditions: 1. If an isochronous device is connected to OHCI/EHCI/xHCI port and is active; 2. Optional PM feature that powers down the internal Bus PLL when the link is in low power state is enabled. Without AMD PLL quirk, USB isochronous stream may stutter or have breaks occasionally, which greatly impair the performance of audio/video streams. Currently AMD PLL quirk is implemented in OHCI and EHCI driver, and will be added to xHCI driver too. They are doing similar things actually, so move the quirk code to pci-quirks.c, which has several advantages: 1. Remove duplicate defines and functions in OHCI/EHCI (and xHCI) driver and make them cleaner; 2. AMD chipset information will be probed only once and then stored. Currently they're probed during every OHCI/EHCI initialization, move the detect code to pci-quirks.c saves the repeat detect cost; 3. Build up synchronization among OHCI/EHCI/xHCI driver. In current code, every host controller enable/disable PLL only according to its own status, and may enable PLL while there is still isoc transfer on other HCs. Move the quirk to pci-quirks.c prevents this issue. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Alex He <alex.he@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-01 13:57:05 +07:00
if (ehci->amd_pll_fix == 1)
usb_amd_quirk_pll_disable();
}
ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs++;
/* fill sITDs frame by frame */
for (packet = sched->first_packet, sitd = NULL;
packet < urb->number_of_packets;
packet++) {
/* ASSERT: we have all necessary sitds */
BUG_ON (list_empty (&sched->td_list));
/* ASSERT: no itds for this endpoint in this frame */
sitd = list_entry (sched->td_list.next,
struct ehci_sitd, sitd_list);
list_move_tail (&sitd->sitd_list, &stream->td_list);
sitd->stream = stream;
sitd->urb = urb;
sitd_patch(ehci, stream, sitd, sched, packet);
sitd_link(ehci, (next_uframe >> 3) & (ehci->periodic_size - 1),
sitd);
next_uframe += stream->uperiod;
}
stream->next_uframe = next_uframe & (mod - 1);
/* don't need that schedule data any more */
iso_sched_free (stream, sched);
urb->hcpriv = stream;
++ehci->isoc_count;
enable_periodic(ehci);
}
/*-------------------------------------------------------------------------*/
#define SITD_ERRS (SITD_STS_ERR | SITD_STS_DBE | SITD_STS_BABBLE \
| SITD_STS_XACT | SITD_STS_MMF)
/* Process and recycle a completed SITD. Return true iff its urb completed,
* and hence its completion callback probably added things to the hardware
* schedule.
*
* Note that we carefully avoid recycling this descriptor until after any
* completion callback runs, so that it won't be reused quickly. That is,
* assuming (a) no more than two urbs per frame on this endpoint, and also
* (b) only this endpoint's completions submit URBs. It seems some silicon
* corrupts things if you reuse completed descriptors very quickly...
*/
static bool sitd_complete(struct ehci_hcd *ehci, struct ehci_sitd *sitd)
{
struct urb *urb = sitd->urb;
struct usb_iso_packet_descriptor *desc;
u32 t;
int urb_index = -1;
struct ehci_iso_stream *stream = sitd->stream;
struct usb_device *dev;
bool retval = false;
urb_index = sitd->index;
desc = &urb->iso_frame_desc [urb_index];
t = hc32_to_cpup(ehci, &sitd->hw_results);
/* report transfer status */
if (unlikely(t & SITD_ERRS)) {
urb->error_count++;
if (t & SITD_STS_DBE)
desc->status = usb_pipein (urb->pipe)
? -ENOSR /* hc couldn't read */
: -ECOMM; /* hc couldn't write */
else if (t & SITD_STS_BABBLE)
desc->status = -EOVERFLOW;
else /* XACT, MMF, etc */
desc->status = -EPROTO;
} else if (unlikely(t & SITD_STS_ACTIVE)) {
/* URB was too late */
urb->error_count++;
} else {
desc->status = 0;
desc->actual_length = desc->length - SITD_LENGTH(t);
urb->actual_length += desc->actual_length;
}
/* handle completion now? */
if ((urb_index + 1) != urb->number_of_packets)
goto done;
/* ASSERT: it's really the last sitd for this urb
list_for_each_entry (sitd, &stream->td_list, sitd_list)
BUG_ON (sitd->urb == urb);
*/
/* give urb back to the driver; completion often (re)submits */
dev = urb->dev;
ehci_urb_done(ehci, urb, 0);
retval = true;
urb = NULL;
--ehci->isoc_count;
disable_periodic(ehci);
ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs--;
if (ehci_to_hcd(ehci)->self.bandwidth_isoc_reqs == 0) {
USB host: Move AMD PLL quirk to pci-quirks.c This patch moves the AMD PLL quirk code in OHCI/EHCI driver to pci-quirks.c, and exports the functions to be used by xHCI driver later. AMD PLL quirk disable the optional PM feature inside specific SB700/SB800/Hudson-2/3 platforms under the following conditions: 1. If an isochronous device is connected to OHCI/EHCI/xHCI port and is active; 2. Optional PM feature that powers down the internal Bus PLL when the link is in low power state is enabled. Without AMD PLL quirk, USB isochronous stream may stutter or have breaks occasionally, which greatly impair the performance of audio/video streams. Currently AMD PLL quirk is implemented in OHCI and EHCI driver, and will be added to xHCI driver too. They are doing similar things actually, so move the quirk code to pci-quirks.c, which has several advantages: 1. Remove duplicate defines and functions in OHCI/EHCI (and xHCI) driver and make them cleaner; 2. AMD chipset information will be probed only once and then stored. Currently they're probed during every OHCI/EHCI initialization, move the detect code to pci-quirks.c saves the repeat detect cost; 3. Build up synchronization among OHCI/EHCI/xHCI driver. In current code, every host controller enable/disable PLL only according to its own status, and may enable PLL while there is still isoc transfer on other HCs. Move the quirk to pci-quirks.c prevents this issue. Signed-off-by: Andiry Xu <andiry.xu@amd.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Alex He <alex.he@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-01 13:57:05 +07:00
if (ehci->amd_pll_fix == 1)
usb_amd_quirk_pll_enable();
}
if (list_is_singular(&stream->td_list))
ehci_to_hcd(ehci)->self.bandwidth_allocated
-= stream->bandwidth;
done:
sitd->urb = NULL;
/* Add to the end of the free list for later reuse */
list_move_tail(&sitd->sitd_list, &stream->free_list);
/* Recycle the siTDs when the pipeline is empty (ep no longer in use) */
if (list_empty(&stream->td_list)) {
list_splice_tail_init(&stream->free_list,
&ehci->cached_sitd_list);
start_free_itds(ehci);
}
return retval;
}
static int sitd_submit (struct ehci_hcd *ehci, struct urb *urb,
gfp_t mem_flags)
{
int status = -EINVAL;
unsigned long flags;
struct ehci_iso_stream *stream;
/* Get iso_stream head */
stream = iso_stream_find (ehci, urb);
if (stream == NULL) {
ehci_dbg (ehci, "can't get iso stream\n");
return -ENOMEM;
}
if (urb->interval != stream->ps.period) {
ehci_dbg (ehci, "can't change iso interval %d --> %d\n",
stream->ps.period, urb->interval);
goto done;
}
#ifdef EHCI_URB_TRACE
ehci_dbg (ehci,
"submit %p dev%s ep%d%s-iso len %d\n",
urb, urb->dev->devpath,
usb_pipeendpoint (urb->pipe),
usb_pipein (urb->pipe) ? "in" : "out",
urb->transfer_buffer_length);
#endif
/* allocate SITDs */
status = sitd_urb_transaction (stream, ehci, urb, mem_flags);
if (status < 0) {
ehci_dbg (ehci, "can't init sitds\n");
goto done;
}
/* schedule ... need to lock */
spin_lock_irqsave (&ehci->lock, flags);
if (unlikely(!HCD_HW_ACCESSIBLE(ehci_to_hcd(ehci)))) {
status = -ESHUTDOWN;
goto done_not_linked;
}
status = usb_hcd_link_urb_to_ep(ehci_to_hcd(ehci), urb);
if (unlikely(status))
goto done_not_linked;
status = iso_stream_schedule(ehci, urb, stream);
if (likely(status == 0)) {
sitd_link_urb (ehci, urb, ehci->periodic_size << 3, stream);
} else if (status > 0) {
status = 0;
ehci_urb_done(ehci, urb, 0);
} else {
usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
}
done_not_linked:
spin_unlock_irqrestore (&ehci->lock, flags);
done:
return status;
}
/*-------------------------------------------------------------------------*/
static void scan_isoc(struct ehci_hcd *ehci)
{
unsigned uf, now_frame, frame;
unsigned fmask = ehci->periodic_size - 1;
bool modified, live;
/*
* When running, scan from last scan point up to "now"
* else clean up by scanning everything that's left.
* Touches as few pages as possible: cache-friendly.
*/
if (ehci->rh_state >= EHCI_RH_RUNNING) {
uf = ehci_read_frame_index(ehci);
now_frame = (uf >> 3) & fmask;
live = true;
} else {
EHCI: improved logic for isochronous scheduling This patch (as1608) reworks the logic used by ehci-hcd for scheduling isochronous transfers. Now the modular calculations are all based on a window that starts at the last frame scanned for isochronous completions. No transfer descriptors for any earlier frames can possibly remain on the schedule, so there can be no confusion from schedule wrap-around. This removes the need for a "slop" region of arbitrary size. There's no need to check for URBs that are longer than the schedule length. With the old code they could throw things off by wrapping around and appearing to end in the near future rather than the distant future. Now such confusion isn't possible, and the existing test for submissions that extend too far into the future will also catch those that exceed the schedule length. (But there still has to be an initial test to handle the case where the schedule already extends as far into the future as possible.) Delays caused by IRQ latency won't confuse the algorithm unless they are ridiculously long (over 250 ms); they will merely reduce how far into the future new transfers can be scheduled. A few people have reported problems caused by delays of 50 ms or so. Now instead of failing completely, isochronous transfers will experience a brief glitch and then continue normally. (Whether this is truly a good thing is debatable. A latency as large as 50 ms generally indicates a bug is present, and complete failure of audio or video transfers draws people's attention pretty vividly. Making the transfers more robust also makes it easier for such bugs to remain undetected.) Finally, ehci->next_frame is renamed to ehci->last_iso_frame, because that better describes what it is: the last frame to have been scanned for isochronous completions. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-29 03:01:23 +07:00
now_frame = (ehci->last_iso_frame - 1) & fmask;
live = false;
}
ehci->now_frame = now_frame;
frame = ehci->last_iso_frame;
for (;;) {
union ehci_shadow q, *q_p;
__hc32 type, *hw_p;
restart:
/* scan each element in frame's queue for completions */
q_p = &ehci->pshadow [frame];
hw_p = &ehci->periodic [frame];
q.ptr = q_p->ptr;
type = Q_NEXT_TYPE(ehci, *hw_p);
modified = false;
while (q.ptr != NULL) {
switch (hc32_to_cpu(ehci, type)) {
case Q_TYPE_ITD:
/* If this ITD is still active, leave it for
* later processing ... check the next entry.
* No need to check for activity unless the
* frame is current.
*/
if (frame == now_frame && live) {
rmb();
for (uf = 0; uf < 8; uf++) {
if (q.itd->hw_transaction[uf] &
ITD_ACTIVE(ehci))
break;
}
if (uf < 8) {
q_p = &q.itd->itd_next;
hw_p = &q.itd->hw_next;
type = Q_NEXT_TYPE(ehci,
q.itd->hw_next);
q = *q_p;
break;
}
}
/* Take finished ITDs out of the schedule
* and process them: recycle, maybe report
* URB completion. HC won't cache the
* pointer for much longer, if at all.
*/
*q_p = q.itd->itd_next;
if (!ehci->use_dummy_qh ||
q.itd->hw_next != EHCI_LIST_END(ehci))
*hw_p = q.itd->hw_next;
else
*hw_p = cpu_to_hc32(ehci,
ehci->dummy->qh_dma);
type = Q_NEXT_TYPE(ehci, q.itd->hw_next);
wmb();
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 20:55:46 +07:00
modified = itd_complete (ehci, q.itd);
q = *q_p;
break;
case Q_TYPE_SITD:
/* If this SITD is still active, leave it for
* later processing ... check the next entry.
* No need to check for activity unless the
* frame is current.
*/
if (((frame == now_frame) ||
(((frame + 1) & fmask) == now_frame))
&& live
&& (q.sitd->hw_results &
SITD_ACTIVE(ehci))) {
q_p = &q.sitd->sitd_next;
hw_p = &q.sitd->hw_next;
type = Q_NEXT_TYPE(ehci,
q.sitd->hw_next);
q = *q_p;
break;
}
/* Take finished SITDs out of the schedule
* and process them: recycle, maybe report
* URB completion.
*/
*q_p = q.sitd->sitd_next;
if (!ehci->use_dummy_qh ||
q.sitd->hw_next != EHCI_LIST_END(ehci))
*hw_p = q.sitd->hw_next;
else
*hw_p = cpu_to_hc32(ehci,
ehci->dummy->qh_dma);
type = Q_NEXT_TYPE(ehci, q.sitd->hw_next);
wmb();
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 20:55:46 +07:00
modified = sitd_complete (ehci, q.sitd);
q = *q_p;
break;
default:
ehci_dbg(ehci, "corrupt type %d frame %d shadow %p\n",
type, frame, q.ptr);
// BUG ();
/* FALL THROUGH */
case Q_TYPE_QH:
case Q_TYPE_FSTN:
/* End of the iTDs and siTDs */
q.ptr = NULL;
break;
}
/* assume completion callbacks modify the queue */
if (unlikely(modified && ehci->isoc_count > 0))
goto restart;
}
/* Stop when we have reached the current frame */
if (frame == now_frame)
break;
/* The last frame may still have active siTDs */
ehci->last_iso_frame = frame;
frame = (frame + 1) & fmask;
}
}