On Tue Apr 22, 2025 at 2:00 PM BST, Alex Deucher wrote: > On Mon, Apr 21, 2025 at 10:21 PM Alexey Klimov <alexey.kli...@linaro.org> > wrote: >> >> On Thu Apr 17, 2025 at 2:08 PM BST, Alex Deucher wrote: >> > On Wed, Apr 16, 2025 at 8:43 PM Fugang Duan <fugang.d...@cixtech.com> >> > wrote: >> >> >> >> 发件人: Alex Deucher <alexdeuc...@gmail.com> 发送时间: 2025年4月16日 22:49 >> >> >收件人: Alexey Klimov <alexey.kli...@linaro.org> >> >> >On Wed, Apr 16, 2025 at 9:48 AM Alexey Klimov <alexey.kli...@linaro.org> >> >> >wrote: >> >> >> >> >> >> On Wed Apr 16, 2025 at 4:12 AM BST, Fugang Duan wrote: >> >> >> > 发件人: Alexey Klimov <alexey.kli...@linaro.org> 发送时间: 2025年4月16 >> >> >日 2:28 >> >> >> >>#regzbot introduced: v6.12..v6.13 >> >> >> >>The only change related to hdp_v5_0_flush_hdp() was >> >> >> >>cf424020e040 drm/amdgpu/hdp5.0: do a posting read when flushing HDP >> >> >> >> >> >> >> >>Reverting that commit ^^ did help and resolved that problem. Before
[..] >> > OK. that patch won't change anything then. Can you try this patch >> > instead? >> >> Config I am using is basically defconfig wrt memory parameters, yeah, i use >> 4k. >> >> So I tested that patch, thank you, and some other different configurations -- >> nothing helped. Exactly the same behaviour with the same backtrace. > > Did you test the first (4k check) or the second (don't remap on ARM) patch? The second one. I think you mentioned that first one won't help for 4k pages. >> So it seems that it is firmware problem after all? > > There is no GPU firmware involved in this operation. It's just a > posted write. E.g., we write to a register to flush the HDP write > queue and then read the register back to make sure the write posted. > If the second patch didn't help, then perhaps there is some issue with > MMIO access on your platform? I didn't mean GPU firmware at all. I only had uefi/EL3 firmwares in mind. Completely out of the blue, based on nothing, do you think that adding delay/some mem barrier between write and read might help? I wonder if host data path code should be executed during common desktop usage as a common user then why it doesn't break later. But yeah, I also think this is this motherboard problem. Thank you. Thanks, Alexey
