RE: [PATCH] drm/amd/pm: avoid duplicate powergate/ungate setting

["Quan, Evan" <Evan.Quan@amd.com>]

[AMD Official Use Only]



> -----Original Message-----
> From: Paul Menzel <pmenzel@molgen.mpg.de>
> Sent: Monday, November 8, 2021 4:51 PM
> To: Quan, Evan <Evan.Quan@amd.com>
> Cc: Deucher, Alexander <Alexander.Deucher@amd.com>; Lazar, Lijo
> <Lijo.Lazar@amd.com>; Borislav Petkov <bp@suse.de>; amd-
> gfx@lists.freedesktop.org
> Subject: Re: [PATCH] drm/amd/pm: avoid duplicate powergate/ungate
> setting
> 
> Dear Evan,
> 
> 
> Am 08.11.21 um 05:47 schrieb Evan Quan:
> > Just bail out if the target IP block is already in the desired
> > powergate/ungate state. This can avoid some duplicate settings which
> > sometime may cause unexpected issues.
> 
> sometime*s*
> 
> Please elaborate the kind of issues.
> 
> On what systems did you test this? Also, there is a new debug log message.
[Quan, Evan] Locally I verified this on my Polaris12 card and Boris helped to verify on his Carrizo platform. Both show positive results.
The log message was left intentionally. But I downgraded the log level from INFO to DEBUG to avoid confusing.
> 
> > Change-Id: I66346c69f121df0f5ee20182451313ae4fda2d04
> > Signed-off-by: Evan Quan <evan.quan@amd.com>
> > Tested-by: Borislav Petkov <bp@suse.de>
> > ---
> >   drivers/gpu/drm/amd/amdgpu/amdgpu.h              |  7 +++++++
> >   drivers/gpu/drm/amd/include/amd_shared.h         |  3 ++-
> >   drivers/gpu/drm/amd/pm/amdgpu_dpm.c              | 13 ++++++++++++-
> >   drivers/gpu/drm/amd/pm/powerplay/amd_powerplay.c |  3 +++
> >   drivers/gpu/drm/amd/pm/powerplay/kv_dpm.c        |  3 +++
> >   drivers/gpu/drm/amd/pm/powerplay/si_dpm.c        |  3 +++
> >   drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c        |  3 +++
> >   7 files changed, 33 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > index b85b67a88a3d..19fa21ad8a44 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> > @@ -767,9 +767,16 @@ enum amd_hw_ip_block_type {
> >   #define HW_ID_MAX		300
> >   #define IP_VERSION(mj, mn, rv) (((mj) << 16) | ((mn) << 8) | (rv))
> >
> > +enum amd_ip_powergate_state {
> > +	POWERGATE_STATE_INITIAL,
> > +	POWERGATE_STATE_GATE,
> > +	POWERGATE_STATE_UNGATE,
> > +};
> > +
> >   struct amd_powerplay {
> >   	void *pp_handle;
> >   	const struct amd_pm_funcs *pp_funcs;
> > +	atomic_t pg_state[AMD_IP_BLOCK_TYPE_NUM];
> >   };
> >
> >   /* polaris10 kickers */
> > diff --git a/drivers/gpu/drm/amd/include/amd_shared.h
> > b/drivers/gpu/drm/amd/include/amd_shared.h
> > index f1a46d16f7ea..4b9e68a79f06 100644
> > --- a/drivers/gpu/drm/amd/include/amd_shared.h
> > +++ b/drivers/gpu/drm/amd/include/amd_shared.h
> > @@ -98,7 +98,8 @@ enum amd_ip_block_type {
> >   	AMD_IP_BLOCK_TYPE_ACP,
> >   	AMD_IP_BLOCK_TYPE_VCN,
> >   	AMD_IP_BLOCK_TYPE_MES,
> > -	AMD_IP_BLOCK_TYPE_JPEG
> > +	AMD_IP_BLOCK_TYPE_JPEG,
> > +	AMD_IP_BLOCK_TYPE_NUM,
> >   };
> >
> >   enum amd_clockgating_state {
> > diff --git a/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> > b/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> > index 03581d5b1836..a6b337b6f4a9 100644
> > --- a/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> > +++ b/drivers/gpu/drm/amd/pm/amdgpu_dpm.c
> > @@ -927,6 +927,14 @@ int
> amdgpu_dpm_set_powergating_by_smu(struct amdgpu_device *adev,
> uint32_t block
> >   {
> >   	int ret = 0;
> >   	const struct amd_pm_funcs *pp_funcs = adev->powerplay.pp_funcs;
> > +	enum amd_ip_powergate_state pg_state =
> > +		gate ? POWERGATE_STATE_GATE :
> POWERGATE_STATE_UNGATE;
> > +
> > +	if (atomic_read(&adev->powerplay.pg_state[block_type]) ==
> pg_state) {
> > +		dev_dbg(adev->dev, "IP block%d already in the target %s
> state!",
> > +				block_type, gate ? "gate" : "ungate");
> > +		return 0;
> > +	}
> >
> >   	switch (block_type) {
> >   	case AMD_IP_BLOCK_TYPE_UVD:
> > @@ -976,9 +984,12 @@ int
> amdgpu_dpm_set_powergating_by_smu(struct amdgpu_device *adev,
> uint32_t block
> >   		}
> >   		break;
> >   	default:
> > -		break;
> > +		return -EINVAL;
> >   	}
> >
> > +	if (!ret)
> > +		atomic_set(&adev->powerplay.pg_state[block_type],
> pg_state);
> > +
> >   	return ret;
> >   }
> >
> > diff --git a/drivers/gpu/drm/amd/pm/powerplay/amd_powerplay.c
> > b/drivers/gpu/drm/amd/pm/powerplay/amd_powerplay.c
> > index bba7479f6265..8d8a7cf615eb 100644
> > --- a/drivers/gpu/drm/amd/pm/powerplay/amd_powerplay.c
> > +++ b/drivers/gpu/drm/amd/pm/powerplay/amd_powerplay.c
> > @@ -38,6 +38,7 @@ static const struct amd_pm_funcs pp_dpm_funcs;
> >   static int amd_powerplay_create(struct amdgpu_device *adev)
> >   {
> >   	struct pp_hwmgr *hwmgr;
> > +	int i;
> 
> I’d use `unsigned int` or `size_t` to make it clear, that they cannot get
> negative.
[Quan, Evan] Sure, I can do that.

BR
Evan
> 
> >
> >   	if (adev == NULL)
> >   		return -EINVAL;
> > @@ -57,6 +58,8 @@ static int amd_powerplay_create(struct
> amdgpu_device *adev)
> >   	hwmgr->display_config = &adev->pm.pm_display_cfg;
> >   	adev->powerplay.pp_handle = hwmgr;
> >   	adev->powerplay.pp_funcs = &pp_dpm_funcs;
> > +	for (i = 0; i < AMD_IP_BLOCK_TYPE_NUM; i++)
> > +		atomic_set(&adev->powerplay.pg_state[i],
> POWERGATE_STATE_INITIAL);
> >   	return 0;
> >   }
> >
> > diff --git a/drivers/gpu/drm/amd/pm/powerplay/kv_dpm.c
> > b/drivers/gpu/drm/amd/pm/powerplay/kv_dpm.c
> > index bcae42cef374..f84f56552fd0 100644
> > --- a/drivers/gpu/drm/amd/pm/powerplay/kv_dpm.c
> > +++ b/drivers/gpu/drm/amd/pm/powerplay/kv_dpm.c
> > @@ -2965,9 +2965,12 @@ static int kv_dpm_get_temp(void *handle)
> >   static int kv_dpm_early_init(void *handle)
> >   {
> >   	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
> > +	int i;
> >
> >   	adev->powerplay.pp_funcs = &kv_dpm_funcs;
> >   	adev->powerplay.pp_handle = adev;
> > +	for (i = 0; i < AMD_IP_BLOCK_TYPE_NUM; i++)
> > +		atomic_set(&adev->powerplay.pg_state[i],
> POWERGATE_STATE_INITIAL);
> >   	kv_dpm_set_irq_funcs(adev);
> >
> >   	return 0;
> > diff --git a/drivers/gpu/drm/amd/pm/powerplay/si_dpm.c
> > b/drivers/gpu/drm/amd/pm/powerplay/si_dpm.c
> > index 81f82aa05ec2..f1eb22c9bb59 100644
> > --- a/drivers/gpu/drm/amd/pm/powerplay/si_dpm.c
> > +++ b/drivers/gpu/drm/amd/pm/powerplay/si_dpm.c
> > @@ -7916,9 +7916,12 @@ static int si_dpm_early_init(void *handle)
> >   {
> >
> >   	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
> > +	int i;
> >
> >   	adev->powerplay.pp_funcs = &si_dpm_funcs;
> >   	adev->powerplay.pp_handle = adev;
> > +	for (i = 0; i < AMD_IP_BLOCK_TYPE_NUM; i++)
> > +		atomic_set(&adev->powerplay.pg_state[i],
> POWERGATE_STATE_INITIAL);
> >   	si_dpm_set_irq_funcs(adev);
> >   	return 0;
> >   }
> > diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > index 01168b8955bf..fdc25bae8237 100644
> > --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
> > @@ -627,6 +627,7 @@ static int smu_early_init(void *handle)
> >   {
> >   	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
> >   	struct smu_context *smu = &adev->smu;
> > +	int i;
> >
> >   	smu->adev = adev;
> >   	smu->pm_enabled = !!amdgpu_dpm;
> > @@ -639,6 +640,8 @@ static int smu_early_init(void *handle)
> >
> >   	adev->powerplay.pp_handle = smu;
> >   	adev->powerplay.pp_funcs = &swsmu_pm_funcs;
> > +	for (i = 0; i < AMD_IP_BLOCK_TYPE_NUM; i++)
> > +		atomic_set(&adev->powerplay.pg_state[i],
> POWERGATE_STATE_INITIAL);
> >
> >   	return smu_set_funcs(adev);
> >   }
> >