From: Tomi Valkeinen tomi.valkeinen@ti.com
Do not update the next frame buffer close to vertical blank. This is to avoid situation when the frame changes between writing of LCDC_DMA_FB_BASE_ADDR_0_REG and LCDC_DMA_FB_CEILING_ADDR_0_REG.
Signed-off-by: Tomi Valkeinen tomi.valkeinen@ti.com [Added description to the patch] Signed-off-by: Jyri Sarha jsarha@ti.com --- drivers/gpu/drm/tilcdc/tilcdc_crtc.c | 61 +++++++++++++++++++++++++++++++----- 1 file changed, 53 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c index 32572285..b1df046 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c @@ -21,6 +21,8 @@ #include "tilcdc_drv.h" #include "tilcdc_regs.h"
+#define TILCDC_VBLANK_SAFETY_THRESHOLD_US 1000 + struct tilcdc_crtc { struct drm_crtc base;
@@ -29,8 +31,12 @@ struct tilcdc_crtc { int dpms; wait_queue_head_t frame_done_wq; bool frame_done; + spinlock_t irq_lock; + + ktime_t last_vblank;
struct drm_framebuffer *curr_fb; + struct drm_framebuffer *next_fb;
/* for deferred fb unref's: */ struct drm_flip_work unref_work; @@ -146,6 +152,8 @@ static int tilcdc_crtc_page_flip(struct drm_crtc *crtc, struct drm_device *dev = crtc->dev; int r; unsigned long flags; + s64 tdiff; + ktime_t next_vblank;
r = tilcdc_verify_fb(crtc, fb); if (r) @@ -162,12 +170,21 @@ static int tilcdc_crtc_page_flip(struct drm_crtc *crtc,
pm_runtime_get_sync(dev->dev);
+ spin_lock_irqsave(&tilcdc_crtc->irq_lock, flags); + + next_vblank = ktime_add_us(tilcdc_crtc->last_vblank, + 1000000 / crtc->hwmode.vrefresh);
- set_scanout(crtc, fb); + tdiff = ktime_to_us(ktime_sub(next_vblank, ktime_get())); + + if (tdiff >= TILCDC_VBLANK_SAFETY_THRESHOLD_US) + set_scanout(crtc, fb); + else + tilcdc_crtc->next_fb = fb;
- spin_lock_irqsave(&dev->event_lock, flags); tilcdc_crtc->event = event; - spin_unlock_irqrestore(&dev->event_lock, flags); + + spin_unlock_irqrestore(&tilcdc_crtc->irq_lock, flags);
pm_runtime_put_sync(dev->dev);
@@ -211,6 +228,12 @@ void tilcdc_crtc_dpms(struct drm_crtc *crtc, int mode)
pm_runtime_put_sync(dev->dev);
+ if (tilcdc_crtc->next_fb) { + drm_flip_work_queue(&tilcdc_crtc->unref_work, + tilcdc_crtc->next_fb); + tilcdc_crtc->next_fb = NULL; + } + if (tilcdc_crtc->curr_fb) { drm_flip_work_queue(&tilcdc_crtc->unref_work, tilcdc_crtc->curr_fb); @@ -651,19 +674,39 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
if (stat & LCDC_END_OF_FRAME0) { unsigned long flags; + bool skip_event = false; + ktime_t now; + + now = ktime_get();
drm_flip_work_commit(&tilcdc_crtc->unref_work, priv->wq);
+ spin_lock_irqsave(&tilcdc_crtc->irq_lock, flags); + + tilcdc_crtc->last_vblank = now; + + if (tilcdc_crtc->next_fb) { + set_scanout(crtc, tilcdc_crtc->next_fb); + tilcdc_crtc->next_fb = NULL; + skip_event = true; + } + + spin_unlock_irqrestore(&tilcdc_crtc->irq_lock, flags); + drm_handle_vblank(dev, 0);
- spin_lock_irqsave(&dev->event_lock, flags); + if (!skip_event) { + struct drm_pending_vblank_event *event;
- if (tilcdc_crtc->event) { - drm_send_vblank_event(dev, 0, tilcdc_crtc->event); + spin_lock_irqsave(&dev->event_lock, flags); + + event = tilcdc_crtc->event; tilcdc_crtc->event = NULL; - } + if (event) + drm_send_vblank_event(dev, 0, event);
- spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irqrestore(&dev->event_lock, flags); + } }
if (priv->rev == 2) { @@ -697,6 +740,8 @@ struct drm_crtc *tilcdc_crtc_create(struct drm_device *dev) drm_flip_work_init(&tilcdc_crtc->unref_work, "unref", unref_worker);
+ spin_lock_init(&tilcdc_crtc->irq_lock); + ret = drm_crtc_init(dev, crtc, &tilcdc_crtc_funcs); if (ret < 0) goto fail;