linux_dsm_epyc7002/drivers/gpu/drm/meson/meson_crtc.c
Neil Armstrong 2bcd3ecab7 drm/meson: Fixes for drm_crtc_vblank_on/off support
Since Linux 4.17, calls to drm_crtc_vblank_on/off are mandatory, and we get
a warning when ctrc is disabled :
" driver forgot to call drm_crtc_vblank_off()"

But, the vsync IRQ was not totally disabled due the transient hardware
state and specific interrupt line, thus adding proper IRQ masking from
the HHI system control registers.

The last change fixes a race condition introduced by calling the added
drm_crtc_vblank_on/off when an HPD event occurs from the HDMI connector,
triggering a WARN_ON() in the _atomic_begin() callback when the CRTC
is disabled, thus also triggering a WARN_ON() in drm_vblank_put() :

WARNING: CPU: 0 PID: 1185 at drivers/gpu/drm/meson/meson_crtc.c:157 meson_crtc_atomic_begin+0x78/0x80
[...]
Call trace:
  meson_crtc_atomic_begin+0x78/0x80
  drm_atomic_helper_commit_planes+0x140/0x218
  drm_atomic_helper_commit_tail+0x38/0x80
  commit_tail+0x7c/0x80
  drm_atomic_helper_commit+0xdc/0x150
  drm_atomic_commit+0x54/0x60
  restore_fbdev_mode_atomic+0x198/0x238
  restore_fbdev_mode+0x6c/0x1c0
  drm_fb_helper_restore_fbdev_mode_unlocked+0x7c/0xf0
  drm_fb_helper_set_par+0x34/0x60
  drm_fb_helper_hotplug_event.part.28+0xb8/0xc8
  drm_fbdev_client_hotplug+0xa4/0xe0
  drm_client_dev_hotplug+0x90/0xe0
  drm_kms_helper_hotplug_event+0x3c/0x48
  drm_helper_hpd_irq_event+0x134/0x168
  dw_hdmi_top_thread_irq+0x3c/0x50
[...]
WARNING: CPU: 0 PID: 1185 at drivers/gpu/drm/drm_vblank.c:1026 drm_vblank_put+0xb4/0xc8
[...]
 Call trace:
  drm_vblank_put+0xb4/0xc8
  drm_crtc_vblank_put+0x24/0x30
  drm_atomic_helper_wait_for_vblanks.part.9+0x130/0x2b8
  drm_atomic_helper_commit_tail+0x68/0x80
[...]

The issue is that vblank need to be enabled in any occurrence of :
- atomic_enable()
- atomic_begin() and state->enable == true, which was not the case

Moving the CRTC enable code to a common function and calling in one of
these occurrence solves this race condition and makes sure vblank is
enabled in each call to _atomic_begin() from the HPD event leading to
drm_atomic_helper_commit_planes().

To Summarize :
- Make sure that the CRTC code will call the drm_crtc_vblank_on()/off()
- *Really* mask the Vsync IRQ
- Initialize and enable vblank at the first
  atomic_begin()/_atomic_enable()

Cc: stable@vger.kernel.org # 4.17+
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
[fixed typos+added cc for stable]
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181122160103.10993-1-narmstrong@baylibre.com
Signed-off-by: Sean Paul <seanpaul@chromium.org>
2018-11-26 16:14:27 -05:00

269 lines
7.3 KiB
C

/*
* Copyright (C) 2016 BayLibre, SAS
* Author: Neil Armstrong <narmstrong@baylibre.com>
* Copyright (C) 2015 Amlogic, Inc. All rights reserved.
* Copyright (C) 2014 Endless Mobile
*
* 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, see <http://www.gnu.org/licenses/>.
*
* Written by:
* Jasper St. Pierre <jstpierre@mecheye.net>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <drm/drmP.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_flip_work.h>
#include <drm/drm_crtc_helper.h>
#include "meson_crtc.h"
#include "meson_plane.h"
#include "meson_venc.h"
#include "meson_vpp.h"
#include "meson_viu.h"
#include "meson_canvas.h"
#include "meson_registers.h"
/* CRTC definition */
struct meson_crtc {
struct drm_crtc base;
struct drm_pending_vblank_event *event;
struct meson_drm *priv;
bool enabled;
};
#define to_meson_crtc(x) container_of(x, struct meson_crtc, base)
/* CRTC */
static int meson_crtc_enable_vblank(struct drm_crtc *crtc)
{
struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
struct meson_drm *priv = meson_crtc->priv;
meson_venc_enable_vsync(priv);
return 0;
}
static void meson_crtc_disable_vblank(struct drm_crtc *crtc)
{
struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
struct meson_drm *priv = meson_crtc->priv;
meson_venc_disable_vsync(priv);
}
static const struct drm_crtc_funcs meson_crtc_funcs = {
.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
.destroy = drm_crtc_cleanup,
.page_flip = drm_atomic_helper_page_flip,
.reset = drm_atomic_helper_crtc_reset,
.set_config = drm_atomic_helper_set_config,
.enable_vblank = meson_crtc_enable_vblank,
.disable_vblank = meson_crtc_disable_vblank,
};
static void meson_crtc_enable(struct drm_crtc *crtc)
{
struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
struct drm_crtc_state *crtc_state = crtc->state;
struct meson_drm *priv = meson_crtc->priv;
DRM_DEBUG_DRIVER("\n");
if (!crtc_state) {
DRM_ERROR("Invalid crtc_state\n");
return;
}
/* Enable VPP Postblend */
writel(crtc_state->mode.hdisplay,
priv->io_base + _REG(VPP_POSTBLEND_H_SIZE));
writel_bits_relaxed(VPP_POSTBLEND_ENABLE, VPP_POSTBLEND_ENABLE,
priv->io_base + _REG(VPP_MISC));
drm_crtc_vblank_on(crtc);
meson_crtc->enabled = true;
}
static void meson_crtc_atomic_enable(struct drm_crtc *crtc,
struct drm_crtc_state *old_state)
{
struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
struct meson_drm *priv = meson_crtc->priv;
DRM_DEBUG_DRIVER("\n");
if (!meson_crtc->enabled)
meson_crtc_enable(crtc);
priv->viu.osd1_enabled = true;
}
static void meson_crtc_atomic_disable(struct drm_crtc *crtc,
struct drm_crtc_state *old_state)
{
struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
struct meson_drm *priv = meson_crtc->priv;
drm_crtc_vblank_off(crtc);
priv->viu.osd1_enabled = false;
priv->viu.osd1_commit = false;
/* Disable VPP Postblend */
writel_bits_relaxed(VPP_POSTBLEND_ENABLE, 0,
priv->io_base + _REG(VPP_MISC));
if (crtc->state->event && !crtc->state->active) {
spin_lock_irq(&crtc->dev->event_lock);
drm_crtc_send_vblank_event(crtc, crtc->state->event);
spin_unlock_irq(&crtc->dev->event_lock);
crtc->state->event = NULL;
}
meson_crtc->enabled = false;
}
static void meson_crtc_atomic_begin(struct drm_crtc *crtc,
struct drm_crtc_state *state)
{
struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
unsigned long flags;
if (crtc->state->enable && !meson_crtc->enabled)
meson_crtc_enable(crtc);
if (crtc->state->event) {
WARN_ON(drm_crtc_vblank_get(crtc) != 0);
spin_lock_irqsave(&crtc->dev->event_lock, flags);
meson_crtc->event = crtc->state->event;
spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
crtc->state->event = NULL;
}
}
static void meson_crtc_atomic_flush(struct drm_crtc *crtc,
struct drm_crtc_state *old_crtc_state)
{
struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
struct meson_drm *priv = meson_crtc->priv;
priv->viu.osd1_commit = true;
}
static const struct drm_crtc_helper_funcs meson_crtc_helper_funcs = {
.atomic_begin = meson_crtc_atomic_begin,
.atomic_flush = meson_crtc_atomic_flush,
.atomic_enable = meson_crtc_atomic_enable,
.atomic_disable = meson_crtc_atomic_disable,
};
void meson_crtc_irq(struct meson_drm *priv)
{
struct meson_crtc *meson_crtc = to_meson_crtc(priv->crtc);
unsigned long flags;
/* Update the OSD registers */
if (priv->viu.osd1_enabled && priv->viu.osd1_commit) {
writel_relaxed(priv->viu.osd1_ctrl_stat,
priv->io_base + _REG(VIU_OSD1_CTRL_STAT));
writel_relaxed(priv->viu.osd1_blk0_cfg[0],
priv->io_base + _REG(VIU_OSD1_BLK0_CFG_W0));
writel_relaxed(priv->viu.osd1_blk0_cfg[1],
priv->io_base + _REG(VIU_OSD1_BLK0_CFG_W1));
writel_relaxed(priv->viu.osd1_blk0_cfg[2],
priv->io_base + _REG(VIU_OSD1_BLK0_CFG_W2));
writel_relaxed(priv->viu.osd1_blk0_cfg[3],
priv->io_base + _REG(VIU_OSD1_BLK0_CFG_W3));
writel_relaxed(priv->viu.osd1_blk0_cfg[4],
priv->io_base + _REG(VIU_OSD1_BLK0_CFG_W4));
/* If output is interlace, make use of the Scaler */
if (priv->viu.osd1_interlace) {
struct drm_plane *plane = priv->primary_plane;
struct drm_plane_state *state = plane->state;
struct drm_rect dest = {
.x1 = state->crtc_x,
.y1 = state->crtc_y,
.x2 = state->crtc_x + state->crtc_w,
.y2 = state->crtc_y + state->crtc_h,
};
meson_vpp_setup_interlace_vscaler_osd1(priv, &dest);
} else
meson_vpp_disable_interlace_vscaler_osd1(priv);
meson_canvas_setup(priv, MESON_CANVAS_ID_OSD1,
priv->viu.osd1_addr, priv->viu.osd1_stride,
priv->viu.osd1_height, MESON_CANVAS_WRAP_NONE,
MESON_CANVAS_BLKMODE_LINEAR);
/* Enable OSD1 */
writel_bits_relaxed(VPP_OSD1_POSTBLEND, VPP_OSD1_POSTBLEND,
priv->io_base + _REG(VPP_MISC));
priv->viu.osd1_commit = false;
}
drm_crtc_handle_vblank(priv->crtc);
spin_lock_irqsave(&priv->drm->event_lock, flags);
if (meson_crtc->event) {
drm_crtc_send_vblank_event(priv->crtc, meson_crtc->event);
drm_crtc_vblank_put(priv->crtc);
meson_crtc->event = NULL;
}
spin_unlock_irqrestore(&priv->drm->event_lock, flags);
}
int meson_crtc_create(struct meson_drm *priv)
{
struct meson_crtc *meson_crtc;
struct drm_crtc *crtc;
int ret;
meson_crtc = devm_kzalloc(priv->drm->dev, sizeof(*meson_crtc),
GFP_KERNEL);
if (!meson_crtc)
return -ENOMEM;
meson_crtc->priv = priv;
crtc = &meson_crtc->base;
ret = drm_crtc_init_with_planes(priv->drm, crtc,
priv->primary_plane, NULL,
&meson_crtc_funcs, "meson_crtc");
if (ret) {
dev_err(priv->drm->dev, "Failed to init CRTC\n");
return ret;
}
drm_crtc_helper_add(crtc, &meson_crtc_helper_funcs);
priv->crtc = crtc;
return 0;
}