Hi Carlos, On 9 February 2018 at 18:26, Carlos Rafael Giani <d...@pseudoterminal.org> wrote: > thanks, I got it to work - almost. I am running this on the i.MX6 with > etnaviv. I do get some flickering, however.
Flickering shouldn't be seen. It's possible that you're calling things incorrectly, however. For example: /* render frame A */ buf_a = gbm_bo_lock_front_buffer(surface); drmModePageFlip(fd, fb_a, PAGE_FLIP_EVENT); /* render frame B */ buf_b = gbm_bo_lock_front_buffer(surface); drmModePageFlip(fd, fb_b, PAGE_FLIP_EVENT); At this point, you cannot release _either_ fb_b or fb_a since they are still in use by KMS. The first point at which it is safe to release fb_a is when you get the event from the flip to fb_b having completed. Releasing it earlier will likely cause flickering. > To test if something is wrong with the page flipping, I call drmGetCap() > with DRM_CAP_ASYNC_PAGE_FLIP , and it returns me 0, indicating that async > page flipping is not supported. But this is odd - is this really not > implemented yet for the i.MX6? And why does drmModePageFlip() still work > with DRM_MODE_PAGE_FLIP_EVENT ? Ah. Those are asynchronous in different directions. ASYNC_PAGE_FLIP refers to the display engine not waiting until any rendering is complete to display that buffer (i.e. asking for tearing as you display before rendering completes). PAGE_FLIP_EVENT (also known as nonblocking) refers to drmModePageFlip returning immediately, instead of waiting until the display engine has completed the flip. Cheers, Daniel _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
