On Tue, May 23, 2023 at 12:23 PM Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> wrote: > > > > On 5/23/2023 8:24 AM, Johan Hovold wrote: > > On Fri, May 12, 2023 at 09:13:04PM +0300, Dmitry Baryshkov wrote: > >> On 28/04/2023 02:28, Abhinav Kumar wrote: > >>> On sc7280 where eDP is the primary display, PSR is causing > >>> IGT breakage even for basic test cases like kms_atomic and > >>> kms_atomic_transition. Most often the issue starts with below > >>> stack so providing that as reference > >>> > >>> Call trace: > >>> dpu_encoder_assign_crtc+0x64/0x6c > >>> dpu_crtc_enable+0x188/0x204 > >>> drm_atomic_helper_commit_modeset_enables+0xc0/0x274 > >>> msm_atomic_commit_tail+0x1a8/0x68c > >>> commit_tail+0xb0/0x160 > >>> drm_atomic_helper_commit+0x11c/0x124 > >>> drm_atomic_commit+0xb0/0xdc > >>> drm_atomic_connector_commit_dpms+0xf4/0x110 > >>> drm_mode_obj_set_property_ioctl+0x16c/0x3b0 > >>> drm_connector_property_set_ioctl+0x4c/0x74 > >>> drm_ioctl_kernel+0xec/0x15c > >>> drm_ioctl+0x264/0x408 > >>> __arm64_sys_ioctl+0x9c/0xd4 > >>> invoke_syscall+0x4c/0x110 > >>> el0_svc_common+0x94/0xfc > >>> do_el0_svc+0x3c/0xb0 > >>> el0_svc+0x2c/0x7c > >>> el0t_64_sync_handler+0x48/0x114 > >>> el0t_64_sync+0x190/0x194 > >>> ---[ end trace 0000000000000000 ]--- > >>> [drm-dp] dp_ctrl_push_idle: PUSH_IDLE pattern timedout > >>> > >>> Other basic use-cases still seem to work fine hence add a > >>> a module parameter to allow toggling psr enable/disable till > >>> PSR related issues are hashed out with IGT. > >> > >> For the reference: Bjorn reported that he has issues with VT on a > >> PSR-enabled laptops. This patch fixes the issue for him > > > > Module parameters are almost never warranted, and it is definitely not > > the right way to handle a broken implementation. > > > > I've just sent a revert that unconditionally disables PSR support until > > the implementation has been fixed: > > > > https://lore.kernel.org/lkml/20230523151646.28366-1-johan+linaro@xxxxxxxxxx/ > > > > Johan > > I dont completely agree with this. Even the virtual terminal case was > reported to be fixed by one user but not the other. So it was probably > something missed out either in validation or reproduction steps of the > user who reported it to be fixed OR the user who reported it not fixed. > That needs to be investigated now. > > We should have ideally gone with the modparam with the feature patches > itself knowing that it gets enabled for all sinks if PSR is supported. > > I had discussed with Rob that till we have some more confidence with the > reported issues we would go with the modparam so as to not do the full > revert. > > In this particular case, the one line revert is not really a deal > breaker. In some other implementations, it might not really be so > trivial to revert the feature with a one line change. > > So I would like to understand what is the concern with the mod param if > the maintainers are onboard with it. Tbf, I'd go further in the modparam direction, ie. add a default disabled modparam, but then _also_ enable the modparam in CI and add the failing tests to xfails. I'd rather have xfails in CI than skips. Acked-by: Rob Clark <robdclark@xxxxxxxxx> BR, -R