summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/vc4
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpu/drm/vc4')
-rw-r--r--drivers/gpu/drm/vc4/vc4_crtc.c46
1 files changed, 45 insertions, 1 deletions
diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 83d3b7912fc2..c8650bbcbcb3 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -741,6 +741,7 @@ static irqreturn_t vc4_crtc_irq_handler(int irq, void *data)
struct vc4_async_flip_state {
struct drm_crtc *crtc;
struct drm_framebuffer *fb;
+ struct drm_framebuffer *old_fb;
struct drm_pending_vblank_event *event;
struct vc4_seqno_cb cb;
@@ -770,6 +771,23 @@ vc4_async_page_flip_complete(struct vc4_seqno_cb *cb)
drm_crtc_vblank_put(crtc);
drm_framebuffer_put(flip_state->fb);
+
+ /* Decrement the BO usecnt in order to keep the inc/dec calls balanced
+ * when the planes are updated through the async update path.
+ * FIXME: we should move to generic async-page-flip when it's
+ * available, so that we can get rid of this hand-made cleanup_fb()
+ * logic.
+ */
+ if (flip_state->old_fb) {
+ struct drm_gem_cma_object *cma_bo;
+ struct vc4_bo *bo;
+
+ cma_bo = drm_fb_cma_get_gem_obj(flip_state->old_fb, 0);
+ bo = to_vc4_bo(&cma_bo->base);
+ vc4_bo_dec_usecnt(bo);
+ drm_framebuffer_put(flip_state->old_fb);
+ }
+
kfree(flip_state);
up(&vc4->async_modeset);
@@ -794,9 +812,22 @@ static int vc4_async_page_flip(struct drm_crtc *crtc,
struct drm_gem_cma_object *cma_bo = drm_fb_cma_get_gem_obj(fb, 0);
struct vc4_bo *bo = to_vc4_bo(&cma_bo->base);
+ /* Increment the BO usecnt here, so that we never end up with an
+ * unbalanced number of vc4_bo_{dec,inc}_usecnt() calls when the
+ * plane is later updated through the non-async path.
+ * FIXME: we should move to generic async-page-flip when it's
+ * available, so that we can get rid of this hand-made prepare_fb()
+ * logic.
+ */
+ ret = vc4_bo_inc_usecnt(bo);
+ if (ret)
+ return ret;
+
flip_state = kzalloc(sizeof(*flip_state), GFP_KERNEL);
- if (!flip_state)
+ if (!flip_state) {
+ vc4_bo_dec_usecnt(bo);
return -ENOMEM;
+ }
drm_framebuffer_get(fb);
flip_state->fb = fb;
@@ -807,10 +838,23 @@ static int vc4_async_page_flip(struct drm_crtc *crtc,
ret = down_interruptible(&vc4->async_modeset);
if (ret) {
drm_framebuffer_put(fb);
+ vc4_bo_dec_usecnt(bo);
kfree(flip_state);
return ret;
}
+ /* Save the current FB before it's replaced by the new one in
+ * drm_atomic_set_fb_for_plane(). We'll need the old FB in
+ * vc4_async_page_flip_complete() to decrement the BO usecnt and keep
+ * it consistent.
+ * FIXME: we should move to generic async-page-flip when it's
+ * available, so that we can get rid of this hand-made cleanup_fb()
+ * logic.
+ */
+ flip_state->old_fb = plane->state->fb;
+ if (flip_state->old_fb)
+ drm_framebuffer_get(flip_state->old_fb);
+
WARN_ON(drm_crtc_vblank_get(crtc) != 0);
/* Immediately update the plane's legacy fb pointer, so that later