[AMD Official Use Only] +Leo to share his insights
> -----Original Message----- > From: Lazar, Lijo <lijo.la...@amd.com> > Sent: Tuesday, August 17, 2021 3:28 PM > To: Quan, Evan <evan.q...@amd.com>; amd-gfx@lists.freedesktop.org > Cc: Deucher, Alexander <alexander.deuc...@amd.com>; Chen, Guchun > <guchun.c...@amd.com>; Pan, Xinhui <xinhui....@amd.com> > Subject: Re: [PATCH] drm/amdgpu: properly powergate Polaris12 UVD/VCE > on suspend > > > > On 8/17/2021 12:10 PM, Evan Quan wrote: > > If the powergating of UVD/VCE is in process, wait for its completion > > before proceeding(suspending). This can fix some hangs observed on > > suspending when UVD/VCE still using(e.g. issue "pm-suspend" when video > > is still playing). > > > > Change-Id: I36f39d9731e0a9638b52d5d92558b0ee9c23a9ed > > Signed-off-by: Evan Quan <evan.q...@amd.com> > > Signed-off-by: xinhui pan <xinhui....@amd.com> > > --- > > drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c | 5 +++++ > > drivers/gpu/drm/amd/amdgpu/vce_v3_0.c | 5 +++++ > > 2 files changed, 10 insertions(+) > > > > diff --git a/drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c > > b/drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c > > index 4eebf973a065..2fdce572baeb 100644 > > --- a/drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c > > +++ b/drivers/gpu/drm/amd/amdgpu/uvd_v6_0.c > > @@ -554,6 +554,11 @@ static int uvd_v6_0_suspend(void *handle) > > int r; > > struct amdgpu_device *adev = (struct amdgpu_device *)handle; > > > > + /* > > + * If the powergating is in process, wait for its completion. > > + */ > > + flush_delayed_work(&adev->uvd.idle_work); > > + > If running idle is a prerequisite before going to suspend, then something else > is missing here. > > Otherwise, the hang looks more like a pending work launched after > hardware is suspended and trying to access hardware. As the hardware is > going to be suspended anyway, doesn't it work with > cancel_delayed_work_sync - making sure that nothing is going to be > launched later to access hardware? [Quan, Evan] The reason we chose flush_delayed_work instead of cancel_delayed_work_sync is we think those operations performed in idle_work(dpm disablement, powergating) seems needed considering the action is 'suspend'. So, instead of "cancel", maybe waiting for them completion is more proper. > > Then this may be a potential issue for other suspend calls also where work is > pending to be launched when hardware is suspended. [Quan, Evan] Do you mean we need to check whether there is similar issue for other IPs? BR Evan > > Thanks, > Lijo > > > r = uvd_v6_0_hw_fini(adev); > > if (r) > > return r; > > diff --git a/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c > > b/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c > > index 6d9108fa22e0..f0adecd5ec0b 100644 > > --- a/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c > > +++ b/drivers/gpu/drm/amd/amdgpu/vce_v3_0.c > > @@ -503,6 +503,11 @@ static int vce_v3_0_suspend(void *handle) > > int r; > > struct amdgpu_device *adev = (struct amdgpu_device *)handle; > > > > + /* > > + * If the powergating is in process, wait for its completion. > > + */ > > + flush_delayed_work(&adev->vce.idle_work); > > + > > r = vce_v3_0_hw_fini(adev); > > if (r) > > return r; > >
