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drm/vc4: Fix VBLANK handling in crtc->enable() path

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When we are enabling a CRTC, drm_crtc_vblank_get() is called before
drm_crtc_vblank_on(), which is not supposed to happen (hence the
WARN_ON() in the code). To solve the problem, we delay the 'update
display list' operation after the CRTC is actually enabled.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: http://patchwork.freedesktop.org/patch/msgid/1498163126-26678-1-git-send-email-boris.brezillon@free-electrons.com
Fixes: 34c8ea400f ("drm/vc4: Mimic drm_atomic_helper_commit() behavior")
This commit is contained in:
Boris Brezillon 2017-06-22 22:25:26 +02:00 committed by Eric Anholt
parent 6f6e0b217a
commit 1ed134e652
1 changed files with 43 additions and 23 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

66
drivers/gpu/drm/vc4/vc4_crtc.c
View file

@ -520,6 +520,34 @@ static void vc4_crtc_disable(struct drm_crtc *crtc)
SCALER_DISPSTATX_EMPTY);
}
static void vc4_crtc_update_dlist(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
struct vc4_dev *vc4 = to_vc4_dev(dev);
struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
if (crtc->state->event) {
unsigned long flags;
crtc->state->event->pipe = drm_crtc_index(crtc);
WARN_ON(drm_crtc_vblank_get(crtc) != 0);
spin_lock_irqsave(&dev->event_lock, flags);
vc4_crtc->event = crtc->state->event;
crtc->state->event = NULL;
HVS_WRITE(SCALER_DISPLISTX(vc4_crtc->channel),
vc4_state->mm.start);
spin_unlock_irqrestore(&dev->event_lock, flags);
} else {
HVS_WRITE(SCALER_DISPLISTX(vc4_crtc->channel),
vc4_state->mm.start);
}
}
static void vc4_crtc_enable(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
@ -530,6 +558,12 @@ static void vc4_crtc_enable(struct drm_crtc *crtc)
require_hvs_enabled(dev);
/* Enable vblank irq handling before crtc is started otherwise
* drm_crtc_get_vblank() fails in vc4_crtc_update_dlist().
*/
drm_crtc_vblank_on(crtc);
vc4_crtc_update_dlist(crtc);
/* Turn on the scaler, which will wait for vstart to start
* compositing.
*/
@ -541,9 +575,6 @@ static void vc4_crtc_enable(struct drm_crtc *crtc)
/* Turn on the pixel valve, which will emit the vstart signal. */
CRTC_WRITE(PV_V_CONTROL,
CRTC_READ(PV_V_CONTROL) | PV_VCONTROL_VIDEN);
/* Enable vblank irq handling after crtc is started. */
drm_crtc_vblank_on(crtc);
}
static bool vc4_crtc_mode_fixup(struct drm_crtc *crtc,
@ -598,7 +629,6 @@ static void vc4_crtc_atomic_flush(struct drm_crtc *crtc,
{
struct drm_device *dev = crtc->dev;
struct vc4_dev *vc4 = to_vc4_dev(dev);
struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
struct drm_plane *plane;
bool debug_dump_regs = false;
@ -620,25 +650,15 @@ static void vc4_crtc_atomic_flush(struct drm_crtc *crtc,
WARN_ON_ONCE(dlist_next - dlist_start != vc4_state->mm.size);
if (crtc->state->event) {
unsigned long flags;
crtc->state->event->pipe = drm_crtc_index(crtc);
WARN_ON(drm_crtc_vblank_get(crtc) != 0);
spin_lock_irqsave(&dev->event_lock, flags);
vc4_crtc->event = crtc->state->event;
crtc->state->event = NULL;
HVS_WRITE(SCALER_DISPLISTX(vc4_crtc->channel),
vc4_state->mm.start);
spin_unlock_irqrestore(&dev->event_lock, flags);
} else {
HVS_WRITE(SCALER_DISPLISTX(vc4_crtc->channel),
vc4_state->mm.start);
}
/* Only update DISPLIST if the CRTC was already running and is not
* being disabled.
* vc4_crtc_enable() takes care of updating the dlist just after
* re-enabling VBLANK interrupts and before enabling the engine.
* If the CRTC is being disabled, there's no point in updating this
* information.
*/
if (crtc->state->active && old_state->active)
vc4_crtc_update_dlist(crtc);
if (debug_dump_regs) {
DRM_INFO("CRTC %d HVS after:\n", drm_crtc_index(crtc));