linux_dsm_epyc7002/drivers/gpu/drm/arm/hdlcd_crtc.c
Robin Murphy 1c81073909 drm/arm/hdlcd: Allow a bit of clock tolerance
On the Arm Juno platform, the HDLCD pixel clock is constrained to 250KHz
resolution in order to avoid the tiny System Control Processor spending
aeons trying to calculate exact PLL coefficients. This means that modes
like my oddball 1600x1200 with 130.89MHz clock get rejected since the
rate cannot be matched exactly. In practice, though, this mode works
quite happily with the clock at 131MHz, so let's relax the check to
allow a little bit of slop.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
2019-06-04 15:12:45 +01:00

336 lines
10 KiB
C

/*
* Copyright (C) 2013-2015 ARM Limited
* Author: Liviu Dudau <Liviu.Dudau@arm.com>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*
* Implementation of a CRTC class for the HDLCD driver.
*/
#include <drm/drmP.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc.h>
#include <drm/drm_fb_cma_helper.h>
#include <drm/drm_fb_helper.h>
#include <drm/drm_gem_cma_helper.h>
#include <drm/drm_of.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_probe_helper.h>
#include <linux/clk.h>
#include <linux/of_graph.h>
#include <linux/platform_data/simplefb.h>
#include <video/videomode.h>
#include "hdlcd_drv.h"
#include "hdlcd_regs.h"
/*
* The HDLCD controller is a dumb RGB streamer that gets connected to
* a single HDMI transmitter or in the case of the ARM Models it gets
* emulated by the software that does the actual rendering.
*
*/
static void hdlcd_crtc_cleanup(struct drm_crtc *crtc)
{
struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
/* stop the controller on cleanup */
hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
drm_crtc_cleanup(crtc);
}
static int hdlcd_crtc_enable_vblank(struct drm_crtc *crtc)
{
struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask | HDLCD_INTERRUPT_VSYNC);
return 0;
}
static void hdlcd_crtc_disable_vblank(struct drm_crtc *crtc)
{
struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask & ~HDLCD_INTERRUPT_VSYNC);
}
static const struct drm_crtc_funcs hdlcd_crtc_funcs = {
.destroy = hdlcd_crtc_cleanup,
.set_config = drm_atomic_helper_set_config,
.page_flip = drm_atomic_helper_page_flip,
.reset = drm_atomic_helper_crtc_reset,
.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
.enable_vblank = hdlcd_crtc_enable_vblank,
.disable_vblank = hdlcd_crtc_disable_vblank,
};
static struct simplefb_format supported_formats[] = SIMPLEFB_FORMATS;
/*
* Setup the HDLCD registers for decoding the pixels out of the framebuffer
*/
static int hdlcd_set_pxl_fmt(struct drm_crtc *crtc)
{
unsigned int btpp;
struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
const struct drm_framebuffer *fb = crtc->primary->state->fb;
uint32_t pixel_format;
struct simplefb_format *format = NULL;
int i;
pixel_format = fb->format->format;
for (i = 0; i < ARRAY_SIZE(supported_formats); i++) {
if (supported_formats[i].fourcc == pixel_format)
format = &supported_formats[i];
}
if (WARN_ON(!format))
return 0;
/* HDLCD uses 'bytes per pixel', zero means 1 byte */
btpp = (format->bits_per_pixel + 7) / 8;
hdlcd_write(hdlcd, HDLCD_REG_PIXEL_FORMAT, (btpp - 1) << 3);
/*
* The format of the HDLCD_REG_<color>_SELECT register is:
* - bits[23:16] - default value for that color component
* - bits[11:8] - number of bits to extract for each color component
* - bits[4:0] - index of the lowest bit to extract
*
* The default color value is used when bits[11:8] are zero, when the
* pixel is outside the visible frame area or when there is a
* buffer underrun.
*/
hdlcd_write(hdlcd, HDLCD_REG_RED_SELECT, format->red.offset |
#ifdef CONFIG_DRM_HDLCD_SHOW_UNDERRUN
0x00ff0000 | /* show underruns in red */
#endif
((format->red.length & 0xf) << 8));
hdlcd_write(hdlcd, HDLCD_REG_GREEN_SELECT, format->green.offset |
((format->green.length & 0xf) << 8));
hdlcd_write(hdlcd, HDLCD_REG_BLUE_SELECT, format->blue.offset |
((format->blue.length & 0xf) << 8));
return 0;
}
static void hdlcd_crtc_mode_set_nofb(struct drm_crtc *crtc)
{
struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
struct drm_display_mode *m = &crtc->state->adjusted_mode;
struct videomode vm;
unsigned int polarities, err;
vm.vfront_porch = m->crtc_vsync_start - m->crtc_vdisplay;
vm.vback_porch = m->crtc_vtotal - m->crtc_vsync_end;
vm.vsync_len = m->crtc_vsync_end - m->crtc_vsync_start;
vm.hfront_porch = m->crtc_hsync_start - m->crtc_hdisplay;
vm.hback_porch = m->crtc_htotal - m->crtc_hsync_end;
vm.hsync_len = m->crtc_hsync_end - m->crtc_hsync_start;
polarities = HDLCD_POLARITY_DATAEN | HDLCD_POLARITY_DATA;
if (m->flags & DRM_MODE_FLAG_PHSYNC)
polarities |= HDLCD_POLARITY_HSYNC;
if (m->flags & DRM_MODE_FLAG_PVSYNC)
polarities |= HDLCD_POLARITY_VSYNC;
/* Allow max number of outstanding requests and largest burst size */
hdlcd_write(hdlcd, HDLCD_REG_BUS_OPTIONS,
HDLCD_BUS_MAX_OUTSTAND | HDLCD_BUS_BURST_16);
hdlcd_write(hdlcd, HDLCD_REG_V_DATA, m->crtc_vdisplay - 1);
hdlcd_write(hdlcd, HDLCD_REG_V_BACK_PORCH, vm.vback_porch - 1);
hdlcd_write(hdlcd, HDLCD_REG_V_FRONT_PORCH, vm.vfront_porch - 1);
hdlcd_write(hdlcd, HDLCD_REG_V_SYNC, vm.vsync_len - 1);
hdlcd_write(hdlcd, HDLCD_REG_H_DATA, m->crtc_hdisplay - 1);
hdlcd_write(hdlcd, HDLCD_REG_H_BACK_PORCH, vm.hback_porch - 1);
hdlcd_write(hdlcd, HDLCD_REG_H_FRONT_PORCH, vm.hfront_porch - 1);
hdlcd_write(hdlcd, HDLCD_REG_H_SYNC, vm.hsync_len - 1);
hdlcd_write(hdlcd, HDLCD_REG_POLARITIES, polarities);
err = hdlcd_set_pxl_fmt(crtc);
if (err)
return;
clk_set_rate(hdlcd->clk, m->crtc_clock * 1000);
}
static void hdlcd_crtc_atomic_enable(struct drm_crtc *crtc,
struct drm_crtc_state *old_state)
{
struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
clk_prepare_enable(hdlcd->clk);
hdlcd_crtc_mode_set_nofb(crtc);
hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 1);
drm_crtc_vblank_on(crtc);
}
static void hdlcd_crtc_atomic_disable(struct drm_crtc *crtc,
struct drm_crtc_state *old_state)
{
struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
drm_crtc_vblank_off(crtc);
hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
clk_disable_unprepare(hdlcd->clk);
}
static enum drm_mode_status hdlcd_crtc_mode_valid(struct drm_crtc *crtc,
const struct drm_display_mode *mode)
{
struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc);
long rate, clk_rate = mode->clock * 1000;
rate = clk_round_rate(hdlcd->clk, clk_rate);
/* 0.1% seems a close enough tolerance for the TDA19988 on Juno */
if (abs(rate - clk_rate) * 1000 > clk_rate) {
/* clock required by mode not supported by hardware */
return MODE_NOCLOCK;
}
return MODE_OK;
}
static void hdlcd_crtc_atomic_begin(struct drm_crtc *crtc,
struct drm_crtc_state *state)
{
struct drm_pending_vblank_event *event = crtc->state->event;
if (event) {
crtc->state->event = NULL;
spin_lock_irq(&crtc->dev->event_lock);
if (drm_crtc_vblank_get(crtc) == 0)
drm_crtc_arm_vblank_event(crtc, event);
else
drm_crtc_send_vblank_event(crtc, event);
spin_unlock_irq(&crtc->dev->event_lock);
}
}
static const struct drm_crtc_helper_funcs hdlcd_crtc_helper_funcs = {
.mode_valid = hdlcd_crtc_mode_valid,
.atomic_begin = hdlcd_crtc_atomic_begin,
.atomic_enable = hdlcd_crtc_atomic_enable,
.atomic_disable = hdlcd_crtc_atomic_disable,
};
static int hdlcd_plane_atomic_check(struct drm_plane *plane,
struct drm_plane_state *state)
{
int i;
struct drm_crtc *crtc;
struct drm_crtc_state *crtc_state;
u32 src_h = state->src_h >> 16;
/* only the HDLCD_REG_FB_LINE_COUNT register has a limit */
if (src_h >= HDLCD_MAX_YRES) {
DRM_DEBUG_KMS("Invalid source width: %d\n", src_h);
return -EINVAL;
}
for_each_new_crtc_in_state(state->state, crtc, crtc_state, i) {
/* we cannot disable the plane while the CRTC is active */
if (!state->fb && crtc_state->active)
return -EINVAL;
return drm_atomic_helper_check_plane_state(state, crtc_state,
DRM_PLANE_HELPER_NO_SCALING,
DRM_PLANE_HELPER_NO_SCALING,
false, true);
}
return 0;
}
static void hdlcd_plane_atomic_update(struct drm_plane *plane,
struct drm_plane_state *state)
{
struct drm_framebuffer *fb = plane->state->fb;
struct hdlcd_drm_private *hdlcd;
u32 dest_h;
dma_addr_t scanout_start;
if (!fb)
return;
dest_h = drm_rect_height(&plane->state->dst);
scanout_start = drm_fb_cma_get_gem_addr(fb, plane->state, 0);
hdlcd = plane->dev->dev_private;
hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_LENGTH, fb->pitches[0]);
hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_PITCH, fb->pitches[0]);
hdlcd_write(hdlcd, HDLCD_REG_FB_LINE_COUNT, dest_h - 1);
hdlcd_write(hdlcd, HDLCD_REG_FB_BASE, scanout_start);
}
static const struct drm_plane_helper_funcs hdlcd_plane_helper_funcs = {
.atomic_check = hdlcd_plane_atomic_check,
.atomic_update = hdlcd_plane_atomic_update,
};
static const struct drm_plane_funcs hdlcd_plane_funcs = {
.update_plane = drm_atomic_helper_update_plane,
.disable_plane = drm_atomic_helper_disable_plane,
.destroy = drm_plane_cleanup,
.reset = drm_atomic_helper_plane_reset,
.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
};
static struct drm_plane *hdlcd_plane_init(struct drm_device *drm)
{
struct hdlcd_drm_private *hdlcd = drm->dev_private;
struct drm_plane *plane = NULL;
u32 formats[ARRAY_SIZE(supported_formats)], i;
int ret;
plane = devm_kzalloc(drm->dev, sizeof(*plane), GFP_KERNEL);
if (!plane)
return ERR_PTR(-ENOMEM);
for (i = 0; i < ARRAY_SIZE(supported_formats); i++)
formats[i] = supported_formats[i].fourcc;
ret = drm_universal_plane_init(drm, plane, 0xff, &hdlcd_plane_funcs,
formats, ARRAY_SIZE(formats),
NULL,
DRM_PLANE_TYPE_PRIMARY, NULL);
if (ret)
return ERR_PTR(ret);
drm_plane_helper_add(plane, &hdlcd_plane_helper_funcs);
hdlcd->plane = plane;
return plane;
}
int hdlcd_setup_crtc(struct drm_device *drm)
{
struct hdlcd_drm_private *hdlcd = drm->dev_private;
struct drm_plane *primary;
int ret;
primary = hdlcd_plane_init(drm);
if (IS_ERR(primary))
return PTR_ERR(primary);
ret = drm_crtc_init_with_planes(drm, &hdlcd->crtc, primary, NULL,
&hdlcd_crtc_funcs, NULL);
if (ret)
return ret;
drm_crtc_helper_add(&hdlcd->crtc, &hdlcd_crtc_helper_funcs);
return 0;
}