From: Rob Clark robdclark@chromium.org
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@chromium.org --- 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;