Hi Chun-Kuang, Missatge de Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> del dia dt., 21 de set. 2021 a les 15:15: > > Hi, Enric: > > Enric Balletbo Serra <eballetbo@xxxxxxxxx> 於 2021年9月21日 週二 下午4:36寫道： > > > > Hi Chun-Kuang, > > > > (again without html format, sorry for the noise) > > > > Missatge de Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> del dia dj., 12 > > d’ag. 2021 a les 2:13: > > > > > > Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> 於 2021年8月9日 週一 上午7:47寫道： > > > > > > > > These refinements include using standard mailbox callback interface, > > > > timeout detection, and a fixed cmdq_handle. > > > > > > For this series, applied to mediatek-drm-next [1]. > > > > > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-next > > > > > > > These patches seem to break the display on the Acer Chromebook R 13 > > (MT8173) in the current mainline. After running a bisection it pointed > > me to the following commit > > > > commit f4be17cd5b14dd73545b0e014a63ebe9ab5ef837 > > Author: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx> > > Date: Sun Jul 4 15:36:48 2021 +0800 > > > > drm/mediatek: Remove struct cmdq_client > > > > Reverting this patch alone is not trivial, so I ended up reverting the > > full series, and I can confirm that reverting the full series makes > > the display work again. > > I think you could not just revert "drm/mediatek: Remove struct > cmdq_client", you should also revert the patches after it, such as > > "drm/mediatek: Clear pending flag when cmdq packet is done" > "drm/mediatek: Add cmdq_handle in mtk_crtc" > "drm/mediatek: Detect CMDQ execution timeout" > Yes, in fact I reverted: 9efb16c2fdd6 drm/mediatek: Clear pending flag when cmdq packet is done bc9241be73d9 drm/mediatek: Add cmdq_handle in mtk_crtc 8cdcb3653424 drm/mediatek: Detect CMDQ execution timeout f4be17cd5b14 drm/mediatek: Remove struct cmdq_client c1ec54b7b5af drm/mediatek: Use mailbox rx_callback instead of cmdq_task_cb Without these patches 5.15-rc2 works again on my platform. The commit 'c1ec54b7b5af drm/mediatek: Use mailbox rx_callback instead of cmdq_task_cb' alone introduces lots of warnings in the kernel WARNING: CPU: 0 PID: 0 at drivers/mailbox/mtk-cmdq-mailbox.c:198 cmdq_task_exec_done+0xb8/0xe0 I think is just a leftover or the mentioned warning, but that confused me a bit doing the bisection. Then, after commit 'f4be17cd5b14 drm/mediatek: Remove struct cmdq_client' my system simply gets stuck. For now I don't see any obvious mistake but will dig further. Can I ask you in which platform did you test? And if you can double check if your platform is broken too in current mainline? Thanks, Enric > If "drm/mediatek: Remove struct cmdq_client" is the patch cause > display abnormal, I think you could compare code w/ and w/o this > patch. Focus on the value accuracy, such as cmdq_cl and cmdq_chan. And > focus on the flow accuracy, such as mtk_drm_crtc_update_config() and > ddp_cmdq_cb(). If this could not find the problem, I think the latest > way is to break this patch into small patches, changes little in each > small patches and we could finally find out the problem. > > Regards, > Chun-Kuang. > > > > > Unfortunately, after the merge window, different things broke for this > > device, and I didn't finish isolating them, and it is not clear to me > > yet whether the logs I'm getting are useful for this specific issue or > > not. Basically with this series merged the kernel seems to be stuck, > > and the display is not working. Latest message is > > > > [ 12.329173] mtk-iommu 10205000.iommu: Partial TLB flush timed out, > > falling back to full flush > > > > Without the series, the kernel goes far and display works, however > > there are other issues affecting the cros-ec, but I think that's > > another issue. > > > > I'll try to dig a bit more, but, meanwhile, if you have any idea > > please let me know. > > > > Thanks, > > Enric > > > > > > > Regards, > > > Chun-Kuang. > > > > > > > > > > > Changes in v2: > > > > 1. Define mtk_drm_cmdq_pkt_create() and mtk_drm_cmdq_pkt_destroy() > > > > when CONFIG_MTK_CMDQ is reachable. > > > > > > > > Chun-Kuang Hu (4): > > > > drm/mediatek: Use mailbox rx_callback instead of cmdq_task_cb > > > > drm/mediatek: Remove struct cmdq_client > > > > drm/mediatek: Detect CMDQ execution timeout > > > > drm/mediatek: Add cmdq_handle in mtk_crtc > > > > > > > > drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 110 ++++++++++++++++++++---- > > > > 1 file changed, 91 insertions(+), 19 deletions(-) > > > > > > > > -- > > > > 2.25.1 > > > >
