[PATCH 3/3] drm/amdgpu: add new INFO IOCTL query for input power

[Alex Deucher]

On Fri, Nov 10, 2023 at 3:22 AM Lazar, Lijo <lijo.lazar at amd.com> wrote:
>
>
>
> On 11/10/2023 3:44 AM, Alex Deucher wrote:
> > Some chips provide both average and input power.  Previously
> > we just exposed average power, add a new query for input
> > power.
> >
>
> Input looks like a misnomer (not the supply side, but the power
> consumed). Better to rename to instantaneous or current power. I guess
> that will require rename of AMDGPU_PP_SENSOR_GPU_INPUT_POWER too.

It aligns with the sysfs naming.  E.g.,
https://www.kernel.org/doc/Documentation/hwmon/sysfs-interface

power[1-*]_input  Instantaneous power use
                            Unit: microWatt
                            RO

Alex

>
> Thanks,
> Lijo
>
> > Example userspace:
> > https://github.com/Umio-Yasuno/libdrm-amdgpu-sys-rs/tree/input_power
> >
> > Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> > ---
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 9 +++++++++
> >   include/uapi/drm/amdgpu_drm.h           | 2 ++
> >   2 files changed, 11 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> > index bf4f48fe438d..48496bb585c7 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> > @@ -1114,6 +1114,15 @@ int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
> >                       }
> >                       ui32 >>= 8;
> >                       break;
> > +             case AMDGPU_INFO_SENSOR_GPU_INPUT_POWER:
> > +                     /* get input GPU power */
> > +                     if (amdgpu_dpm_read_sensor(adev,
> > +                                                AMDGPU_PP_SENSOR_GPU_INPUT_POWER,
> > +                                                (void *)&ui32, &ui32_size)) {
> > +                             return -EINVAL;
> > +                     }
> > +                     ui32 >>= 8;
> > +                     break;
> >               case AMDGPU_INFO_SENSOR_VDDNB:
> >                       /* get VDDNB in millivolts */
> >                       if (amdgpu_dpm_read_sensor(adev,
> > diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
> > index ad21c613fec8..96e32dafd4f0 100644
> > --- a/include/uapi/drm/amdgpu_drm.h
> > +++ b/include/uapi/drm/amdgpu_drm.h
> > @@ -865,6 +865,8 @@ struct drm_amdgpu_cs_chunk_cp_gfx_shadow {
> >       #define AMDGPU_INFO_SENSOR_PEAK_PSTATE_GFX_SCLK                 0xa
> >       /* Subquery id: Query GPU peak pstate memory clock */
> >       #define AMDGPU_INFO_SENSOR_PEAK_PSTATE_GFX_MCLK                 0xb
> > +     /* Subquery id: Query input GPU power   */
> > +     #define AMDGPU_INFO_SENSOR_GPU_INPUT_POWER      0xc
> >   /* Number of VRAM page faults on CPU access. */
> >   #define AMDGPU_INFO_NUM_VRAM_CPU_PAGE_FAULTS        0x1E
> >   #define AMDGPU_INFO_VRAM_LOST_COUNTER               0x1F