drm/msm/mdp4: cure for the cursor blues (v2)

The hw cursor is relatively adept at triggering underflows, which
manifest as a "blue flash" (since blue is configured as the underflow
color).  Juggle a few things around to tighten up the timing for setting
cursor registers in DONE irq.

And most importantly, don't ever disable the hw cursor.  Instead flip it
to a blank/empty cursor.  This seems far more reliable, as even simply
clearing the cursor-enable bit (with no other updates in previous/
following frames) can in some cases cause underflow.

v1: original
v2: add missing locking spotted by Micah

Cc: Micah Richert <richert@braincorporation.com>
Signed-off-by: Rob Clark <robdclark@gmail.com>
This commit is contained in:
Rob Clark 2014-04-22 12:27:28 -04:00
parent 96673ecbd7
commit 7d8d9f6705
5 changed files with 32 additions and 10 deletions

View File

@ -510,9 +510,8 @@ static void update_cursor(struct drm_crtc *crtc)
MDP4_DMA_CURSOR_BLEND_CONFIG_CURSOR_EN);
} else {
/* disable cursor: */
mdp4_write(mdp4_kms, REG_MDP4_DMA_CURSOR_BASE(dma), 0);
mdp4_write(mdp4_kms, REG_MDP4_DMA_CURSOR_BLEND_CONFIG(dma),
MDP4_DMA_CURSOR_BLEND_CONFIG_FORMAT(CURSOR_ARGB));
mdp4_write(mdp4_kms, REG_MDP4_DMA_CURSOR_BASE(dma),
mdp4_kms->blank_cursor_iova);
}
/* and drop the iova ref + obj rev when done scanning out: */
@ -574,11 +573,9 @@ static int mdp4_crtc_cursor_set(struct drm_crtc *crtc,
if (old_bo) {
/* drop our previous reference: */
msm_gem_put_iova(old_bo, mdp4_kms->id);
drm_gem_object_unreference_unlocked(old_bo);
drm_flip_work_queue(&mdp4_crtc->unref_cursor_work, old_bo);
}
crtc_flush(crtc);
request_pending(crtc, PENDING_CURSOR);
return 0;

View File

@ -70,12 +70,12 @@ irqreturn_t mdp4_irq(struct msm_kms *kms)
VERB("status=%08x", status);
mdp_dispatch_irqs(mdp_kms, status);
for (id = 0; id < priv->num_crtcs; id++)
if (status & mdp4_crtc_vblank(priv->crtcs[id]))
drm_handle_vblank(dev, id);
mdp_dispatch_irqs(mdp_kms, status);
return IRQ_HANDLED;
}

View File

@ -144,6 +144,10 @@ static void mdp4_preclose(struct msm_kms *kms, struct drm_file *file)
static void mdp4_destroy(struct msm_kms *kms)
{
struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
if (mdp4_kms->blank_cursor_iova)
msm_gem_put_iova(mdp4_kms->blank_cursor_bo, mdp4_kms->id);
if (mdp4_kms->blank_cursor_bo)
drm_gem_object_unreference(mdp4_kms->blank_cursor_bo);
kfree(mdp4_kms);
}
@ -372,6 +376,23 @@ struct msm_kms *mdp4_kms_init(struct drm_device *dev)
goto fail;
}
mutex_lock(&dev->struct_mutex);
mdp4_kms->blank_cursor_bo = msm_gem_new(dev, SZ_16K, MSM_BO_WC);
mutex_unlock(&dev->struct_mutex);
if (IS_ERR(mdp4_kms->blank_cursor_bo)) {
ret = PTR_ERR(mdp4_kms->blank_cursor_bo);
dev_err(dev->dev, "could not allocate blank-cursor bo: %d\n", ret);
mdp4_kms->blank_cursor_bo = NULL;
goto fail;
}
ret = msm_gem_get_iova(mdp4_kms->blank_cursor_bo, mdp4_kms->id,
&mdp4_kms->blank_cursor_iova);
if (ret) {
dev_err(dev->dev, "could not pin blank-cursor bo: %d\n", ret);
goto fail;
}
return kms;
fail:

View File

@ -44,6 +44,10 @@ struct mdp4_kms {
struct clk *lut_clk;
struct mdp_irq error_handler;
/* empty/blank cursor bo to use when cursor is "disabled" */
struct drm_gem_object *blank_cursor_bo;
uint32_t blank_cursor_iova;
};
#define to_mdp4_kms(x) container_of(x, struct mdp4_kms, base)

View File

@ -71,11 +71,11 @@ static void mdp5_irq_mdp(struct mdp_kms *mdp_kms)
VERB("status=%08x", status);
mdp_dispatch_irqs(mdp_kms, status);
for (id = 0; id < priv->num_crtcs; id++)
if (status & mdp5_crtc_vblank(priv->crtcs[id]))
drm_handle_vblank(dev, id);
mdp_dispatch_irqs(mdp_kms, status);
}
irqreturn_t mdp5_irq(struct msm_kms *kms)