From: Rob Clark <robdclark@xxxxxxxxxxxx>
refcount_t complains about 0->1 transitions, which isn't *quite* what we
wanted. So use dirtyfb==1 to mean that the fb is not connected to any
output that requires dirtyfb flushing, so that we can keep the underflow
and overflow checking.
Fixes: 9e4dde28e9cd ("drm/msm: Avoid dirtyfb stalls on video mode displays (v2)")
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_fb.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/msm_fb.c b/drivers/gpu/drm/msm/msm_fb.c
index 96b379a08327..7137492fe78e 100644
--- a/drivers/gpu/drm/msm/msm_fb.c
+++ b/drivers/gpu/drm/msm/msm_fb.c
@@ -37,7 +37,7 @@ static int msm_framebuffer_dirtyfb(struct drm_framebuffer *fb,
/* If this fb is not used on any display requiring pixel data to be
* flushed, then skip dirtyfb
*/
- if (refcount_read(&msm_fb->dirtyfb) == 0)
+ if (refcount_read(&msm_fb->dirtyfb) == 1)
return 0;
return drm_atomic_helper_dirtyfb(fb, file_priv, flags, color,
@@ -221,6 +221,8 @@ static struct drm_framebuffer *msm_framebuffer_init(struct drm_device *dev,
goto fail;
}
+ refcount_set(&msm_fb->dirtyfb, 1);
+
drm_dbg_state(dev, "create: FB ID: %d (%p)", fb->base.id, fb);
return fb;
--
2.35.1
