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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spamd-Result: default: False [-3.30 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_SHORT(-0.20)[-0.999]; MIME_GOOD(-0.10)[text/plain]; RCVD_VIA_SMTP_AUTH(0.00)[]; FREEMAIL_TO(0.00)[gmail.com,igalia.com]; ARC_NA(0.00)[]; TO_DN_SOME(0.00)[]; MIME_TRACE(0.00)[0:+]; MID_RHS_MATCH_FROM(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_FIVE(0.00)[5]; RCVD_TLS_ALL(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:mid, imap1.dmz-prg2.suse.org:helo, suse.com:url] X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" (cc'ing v3d maintainers Maira and Melissa) Hi Am 23.09.26 um 18:00 schrieb Fabio Piparo: > Hi Thomas, > > Thanks for taking a look. > > On 14.09.26 10:43, Thomas Zimmermann wrote: >> I assume you write these frames quickly one after the other? As i2c is >> really slow, you might write to buffers that are still being transferred >> in the background. >> >> Do you read back the status of the page flips? DRM should tell you when >> it has completed transferring a frame. See [1] > The test renders with the GPU: two dumb buffers allocated on the > ssd130x device and shared with v3d over PRIME. It runs at 10 fps. > Before each flip it calls glFinish(), then flips with > DRM_MODE_PAGE_FLIP_EVENT and waits for the event before drawing into > the other buffer. The same test drawing with the CPU instead comes out > clean. A number of things come to my mind. - Dumb buffers (from ssd130x) are not meant for HW rendering. They are generally for software rendering only. - Hence, the ideomatic use for sharing graphics buffers is to model a producer-consumer relationship. Export the buffer from the device that generates the frame and import it to the buffer that displays it. - Since you're compositor's sharing happens in the opposite direction, ssd130x might not sync correctly. (I'm not sure of v3d requires a dedicated flush.) - Or maybe v3d needs to do a final cache flush after drawing to imported buffers. If nothing else helpers, we could use map_wc for shared buffers in ssd130x, but it seems like papering over something else. Best regards Thomas > > I'm happy to send the test program if it would help. > > Best regards, > Fabio -- -- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com GF: Stefan Gaiser, Jochen Jaser, Abhinav Puri, (HRB 36809, AG Nürnberg)