On 7/4/23 19:06, Sebastian Wick wrote: > On Sat, Jul 1, 2023 at 4:09 AM André Almeida <andrealm...@igalia.com> wrote: >> >> @@ -949,6 +949,15 @@ struct hdr_output_metadata { >> * Request that the page-flip is performed as soon as possible, ie. with no >> * delay due to waiting for vblank. This may cause tearing to be visible on >> * the screen. >> + * >> + * When used with atomic uAPI, the driver will return an error if the >> hardware >> + * doesn't support performing an asynchronous page-flip for this update. >> + * User-space should handle this, e.g. by falling back to a regular >> page-flip. >> + * >> + * Note, some hardware might need to perform one last synchronous page-flip >> + * before being able to switch to asynchronous page-flips. As an exception, >> + * the driver will return success even though that first page-flip is not >> + * asynchronous. > > What would happen if one commits another async KMS update before the > first page flip? Does one receive EAGAIN, does it amend the previous > commit?
Should be the former. DRM_MODE_PAGE_FLIP_ASYNC just means the flip may complete outside of vertical blank, it doesn't change anything else. -- Earthling Michel Dänzer | https://redhat.com Libre software enthusiast | Mesa and Xwayland developer