Re: [PATCH v2] drm/amdgpu/sdma_v4_0: turn off SDMA ring buffer in the s2idle suspend

["Limonciello, Mario" <mario.limonciello@amd.com>]

On 12/1/2022 07:39, Alex Deucher wrote:
> On Thu, Dec 1, 2022 at 2:56 AM Prike Liang <Prike.Liang@amd.com> wrote:
>>
>> In the SDMA s0ix save process requires to turn off SDMA ring buffer for
>> avoiding the SDMA in-flight request, otherwise will suffer from SDMA page
>> fault which causes by page request from in-flight SDMA ring accessing at
>> SDMA restore phase.
>>
>> Link: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitlab.freedesktop.org%2Fdrm%2Famd%2F-%2Fissues%2F2248&amp;data=05%7C01%7CMario.Limonciello%40amd.com%7Cf85681a1e6704044f60708dad3a17d61%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C638054987793833283%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=mUTB99mZYEenu1iBYJSuNRIVClonl5bXtS7jhMJJj30%3D&amp;reserved=0
>> Cc: stable@vger.kernel.org # 6.0 >> Fixes: f8f4e2a51834 ("drm/amdgpu: skipping SDMA hw_init and hw_fini 
for S0ix.")

I double checked and f8f4e2a51834 got backported to 5.15.y too as 
960c8a55016b.

So this should be:

Cc: stable@vger.kernel.org # 5.15

>>
>> Signed-off-by: Prike Liang <Prike.Liang@amd.com>
> 
> Reviewed-by: Alex Deucher <alexander.deucher@amd.com>

Tested-by: Mario Limonciello <mario.limonciello@amd.com>

> 
>> ---
>> -v2: change the name sdma_v4_0_gfx_stop() to sdma_v4_0_gfx_enable() (Lijo)
>> ---
>>   drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c | 24 +++++++++++++++---------
>>   1 file changed, 15 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c b/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
>> index 1122bd4eae98..4d780e4430e7 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
>> @@ -907,13 +907,13 @@ static void sdma_v4_0_ring_emit_fence(struct amdgpu_ring *ring, u64 addr, u64 se
>>
>>
>>   /**
>> - * sdma_v4_0_gfx_stop - stop the gfx async dma engines
>> + * sdma_v4_0_gfx_enable - enable the gfx async dma engines
>>    *
>>    * @adev: amdgpu_device pointer
>> - *
>> - * Stop the gfx async dma ring buffers (VEGA10).
>> + * @enable: enable SDMA RB/IB
>> + * control the gfx async dma ring buffers (VEGA10).
>>    */
>> -static void sdma_v4_0_gfx_stop(struct amdgpu_device *adev)
>> +static void sdma_v4_0_gfx_enable(struct amdgpu_device *adev, bool enable)
>>   {
>>          u32 rb_cntl, ib_cntl;
>>          int i;
>> @@ -922,10 +922,10 @@ static void sdma_v4_0_gfx_stop(struct amdgpu_device *adev)
>>
>>          for (i = 0; i < adev->sdma.num_instances; i++) {
>>                  rb_cntl = RREG32_SDMA(i, mmSDMA0_GFX_RB_CNTL);
>> -               rb_cntl = REG_SET_FIELD(rb_cntl, SDMA0_GFX_RB_CNTL, RB_ENABLE, 0);
>> +               rb_cntl = REG_SET_FIELD(rb_cntl, SDMA0_GFX_RB_CNTL, RB_ENABLE, enable ? 1 : 0);
>>                  WREG32_SDMA(i, mmSDMA0_GFX_RB_CNTL, rb_cntl);
>>                  ib_cntl = RREG32_SDMA(i, mmSDMA0_GFX_IB_CNTL);
>> -               ib_cntl = REG_SET_FIELD(ib_cntl, SDMA0_GFX_IB_CNTL, IB_ENABLE, 0);
>> +               ib_cntl = REG_SET_FIELD(ib_cntl, SDMA0_GFX_IB_CNTL, IB_ENABLE, enable ? 1 : 0);
>>                  WREG32_SDMA(i, mmSDMA0_GFX_IB_CNTL, ib_cntl);
>>          }
>>   }
>> @@ -1044,7 +1044,7 @@ static void sdma_v4_0_enable(struct amdgpu_device *adev, bool enable)
>>          int i;
>>
>>          if (!enable) {
>> -               sdma_v4_0_gfx_stop(adev);
>> +               sdma_v4_0_gfx_enable(adev, enable);
>>                  sdma_v4_0_rlc_stop(adev);
>>                  if (adev->sdma.has_page_queue)
>>                          sdma_v4_0_page_stop(adev);
>> @@ -1960,8 +1960,10 @@ static int sdma_v4_0_suspend(void *handle)
>>          struct amdgpu_device *adev = (struct amdgpu_device *)handle;
>>
>>          /* SMU saves SDMA state for us */
>> -       if (adev->in_s0ix)
>> +       if (adev->in_s0ix) {
>> +               sdma_v4_0_gfx_enable(adev, false);
>>                  return 0;
>> +       }
>>
>>          return sdma_v4_0_hw_fini(adev);
>>   }
>> @@ -1971,8 +1973,12 @@ static int sdma_v4_0_resume(void *handle)
>>          struct amdgpu_device *adev = (struct amdgpu_device *)handle;
>>
>>          /* SMU restores SDMA state for us */
>> -       if (adev->in_s0ix)
>> +       if (adev->in_s0ix) {
>> +               sdma_v4_0_enable(adev, true);
>> +               sdma_v4_0_gfx_enable(adev, true);
>> +               amdgpu_ttm_set_buffer_funcs_status(adev, true);
>>                  return 0;
>> +       }
>>
>>          return sdma_v4_0_hw_init(adev);
>>   }
>> --
>> 2.25.1
>>