[PATCH] drm/amdgpu: Add a new module param to disable d3cold

[Ma, Jun]

Hi Alex,

On 11/30/2023 12:39 AM, Alex Deucher wrote:
> On Wed, Nov 29, 2023 at 11:37 AM Ma Jun <Jun.Ma2 at amd.com> wrote:
>>
>> Some platforms can't resume from d3cold state, So add a
>> new module parameter to disable d3cold state for debugging
>> purpose or workaround.
> 
> Doesn't the runpm parameter already handle this?  If you set runpm=0,
> that should disable d3cold.
> 
runpm=0  prevents calls to driver runtime_suspend/resume functions.
While d3cold=0 allows calls to runtime_suspend/resume functions and puts
the device in d3hot state instead of d3cold.

Regards,
Ma Jun

> Alex
> 
>>
>> Signed-off-by: Ma Jun <Jun.Ma2 at amd.com>
>> ---
>>  drivers/gpu/drm/amd/amdgpu/amdgpu.h        | 1 +
>>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 7 +++++++
>>  drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c    | 8 ++++++++
>>  3 files changed, 16 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> index a9f54df9d33e..db9f60790267 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> @@ -166,6 +166,7 @@ extern char amdgpu_lockup_timeout[AMDGPU_MAX_TIMEOUT_PARAM_LENGTH];
>>  extern int amdgpu_dpm;
>>  extern int amdgpu_fw_load_type;
>>  extern int amdgpu_aspm;
>> +extern int amdgpu_d3cold;
>>  extern int amdgpu_runtime_pm;
>>  extern uint amdgpu_ip_block_mask;
>>  extern int amdgpu_bapm;
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>> index 22b6a910b7f2..90501c44e7d0 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>> @@ -264,6 +264,13 @@ bool amdgpu_device_supports_px(struct drm_device *dev)
>>  bool amdgpu_device_supports_boco(struct drm_device *dev)
>>  {
>>         struct amdgpu_device *adev = drm_to_adev(dev);
>> +       struct pci_dev *parent;
>> +
>> +       if (!amdgpu_d3cold) {
>> +               parent = pcie_find_root_port(adev->pdev);
>> +               pci_d3cold_disable(parent);
>> +               return false;
>> +       }
>>
>>         if (adev->has_pr3 ||
>>             ((adev->flags & AMD_IS_PX) && amdgpu_is_atpx_hybrid()))
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> index 5f14f04cb553..c9fbb8bd4169 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> @@ -145,6 +145,7 @@ char amdgpu_lockup_timeout[AMDGPU_MAX_TIMEOUT_PARAM_LENGTH];
>>  int amdgpu_dpm = -1;
>>  int amdgpu_fw_load_type = -1;
>>  int amdgpu_aspm = -1;
>> +int amdgpu_d3cold = -1;
>>  int amdgpu_runtime_pm = -1;
>>  uint amdgpu_ip_block_mask = 0xffffffff;
>>  int amdgpu_bapm = -1;
>> @@ -359,6 +360,13 @@ module_param_named(fw_load_type, amdgpu_fw_load_type, int, 0444);
>>  MODULE_PARM_DESC(aspm, "ASPM support (1 = enable, 0 = disable, -1 = auto)");
>>  module_param_named(aspm, amdgpu_aspm, int, 0444);
>>
>> +/**
>> + * DOC: d3cold (int)
>> + * To disable d3cold (1 = enable, 0 = disable). The default is -1 (auto, enabled).
>> + */
>> +MODULE_PARM_DESC(d3cold, "d3cold support (1 = enable, 0 = disable, -1 = auto)");
>> +module_param_named(d3cold, amdgpu_d3cold, int, 0444);
>> +
>>  /**
>>   * DOC: runpm (int)
>>   * Override for runtime power management control for dGPUs. The amdgpu driver can dynamically power down
>> --
>> 2.34.1
>>