drm/tilcdc: Recover from sync lost error flood by resetting the LCDC

Recover from sync lost error flood by resetting the LCDC instead of
turning off the SYNC_LOST error IRQ. When LCDC starves on limited
memory bandwidth it may sometimes result an error situation when the
picture may have shifted couple of pixels to right and SYNC_LOST
interrupt is generated on every frame. LCDC main reset recovers from
this situation and causes a brief blanking on the screen.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Tested-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
This commit is contained in:
Jyri Sarha 2016-04-06 14:02:38 +03:00
parent 2d53a18098
commit 13b3d72705

View File

@ -55,6 +55,7 @@ struct tilcdc_crtc {
int sync_lost_count;
bool frame_intact;
struct work_struct recover_work;
};
#define to_tilcdc_crtc(x) container_of(x, struct tilcdc_crtc, base)
@ -252,6 +253,25 @@ static bool tilcdc_crtc_is_on(struct drm_crtc *crtc)
return crtc->state && crtc->state->enable && crtc->state->active;
}
static void tilcdc_crtc_recover_work(struct work_struct *work)
{
struct tilcdc_crtc *tilcdc_crtc =
container_of(work, struct tilcdc_crtc, recover_work);
struct drm_crtc *crtc = &tilcdc_crtc->base;
dev_info(crtc->dev->dev, "%s: Reset CRTC", __func__);
drm_modeset_lock_crtc(crtc, NULL);
if (!tilcdc_crtc_is_on(crtc))
goto out;
tilcdc_crtc_disable(crtc);
tilcdc_crtc_enable(crtc);
out:
drm_modeset_unlock_crtc(crtc);
}
static void tilcdc_crtc_destroy(struct drm_crtc *crtc)
{
struct tilcdc_crtc *tilcdc_crtc = to_tilcdc_crtc(crtc);
@ -838,9 +858,12 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
tilcdc_crtc->frame_intact = false;
if (tilcdc_crtc->sync_lost_count++ >
SYNC_LOST_COUNT_LIMIT) {
dev_err(dev->dev, "%s(0x%08x): Sync lost flood detected, disabling the interrupt", __func__, stat);
dev_err(dev->dev, "%s(0x%08x): Sync lost flood detected, recovering", __func__, stat);
queue_work(system_wq,
&tilcdc_crtc->recover_work);
tilcdc_write(dev, LCDC_INT_ENABLE_CLR_REG,
LCDC_SYNC_LOST);
tilcdc_crtc->sync_lost_count = 0;
}
}
@ -880,6 +903,7 @@ struct drm_crtc *tilcdc_crtc_create(struct drm_device *dev)
"unref", unref_worker);
spin_lock_init(&tilcdc_crtc->irq_lock);
INIT_WORK(&tilcdc_crtc->recover_work, tilcdc_crtc_recover_work);
ret = drm_crtc_init_with_planes(dev, crtc,
&tilcdc_crtc->primary,