Ariel D'Alessandro <[email protected]> 於 2025年10月24日 週五 下午8:28寫道： > > Commit c410fa9b07c32 ("drm/mediatek: Add AFBC support to Mediatek DRM > driver") added AFBC support to Mediatek DRM and enabled the > 32x8/split/sparse modifier. > > However, this is currently broken on Mediatek MT8188 (Genio 700 EVK > platform); tested using upstream Kernel and Mesa (v25.2.1), AFBC is used by > default since Mesa v25.0. > > Kernel trace reports vblank timeouts constantly, and the render is garbled: > > ``` > [CRTC:62:crtc-0] vblank wait timed out > WARNING: CPU: 7 PID: 70 at drivers/gpu/drm/drm_atomic_helper.c:1835 > drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c > [...] > Hardware name: MediaTek Genio-700 EVK (DT) > Workqueue: events_unbound commit_work > pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c > lr : drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c > sp : ffff80008337bca0 > x29: ffff80008337bcd0 x28: 0000000000000061 x27: 0000000000000000 > x26: 0000000000000001 x25: 0000000000000000 x24: ffff0000c9dcc000 > x23: 0000000000000001 x22: 0000000000000000 x21: ffff0000c66f2f80 > x20: ffff0000c0d7d880 x19: 0000000000000000 x18: 000000000000000a > x17: 000000040044ffff x16: 005000f2b5503510 x15: 0000000000000000 > x14: 0000000000000000 x13: 74756f2064656d69 x12: 742074696177206b > x11: 0000000000000058 x10: 0000000000000018 x9 : ffff800082396a70 > x8 : 0000000000057fa8 x7 : 0000000000000cce x6 : ffff8000823eea70 > x5 : ffff0001fef5f408 x4 : ffff80017ccee000 x3 : ffff0000c12cb480 > x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000c12cb480 > Call trace: > drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c (P) > drm_atomic_helper_commit_tail_rpm+0x64/0x80 > commit_tail+0xa4/0x1a4 > commit_work+0x14/0x20 > process_one_work+0x150/0x290 > worker_thread+0x2d0/0x3ec > kthread+0x12c/0x210 > ret_from_fork+0x10/0x20 > ---[ end trace 0000000000000000 ]--- > ``` > > Until this gets fixed upstream, disable AFBC support on this platform, as > it's currently broken with upstream Mesa.
Applied to mediatek-drm-fixes [1], thanks. [1] https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-fixes Regards, Chun-Kuang. > > Signed-off-by: Ariel D'Alessandro <[email protected]> > ---
