On Thu, Mar 05, 2015 at 05:52:50PM -0800, Haixia Shi wrote:
On Thu, Mar 5, 2015 at 2:33 AM, Chris Wilson chris@chris-wilson.co.uk wrote:
On Wed, Mar 04, 2015 at 06:26:23PM -0800, Haixia Shi wrote:
This also limits the maximum frequency of page flips by the vrefresh rate.
Signed-off-by: Haixia Shi hshi@chromium.org Reviewed-by: Stéphane Marchesin marcheu@chromium.org Tested-by: Haixia Shi hshi@chromium.org
I think the better approach would have been to push the task down to udl_handle_damage(). Almost all of the callers would prefer deferred updates (with the notable exception of modesetting). -Chris
I'm not sure this is correct. While there's reasonable expectation for page flips to be asynchronous (when flip completes it would send the vblank event), my understanding is that fb_fillrect, fb_copyarea and fb_imageblit are synchronous.
No, they are not synchronous with monitor refresh. Conceptually running the usb xfer from a timer is the equivalent of the monitor reading from the scanout at a distinct point in time from when we write into the framebuffer. -Chris