[PATCH] drm/amd: Add debug mask for subviewport mclk switch

[Alex Deucher]

On Tue, Jun 28, 2022 at 5:26 PM Aurabindo Pillai
<aurabindo.pillai at amd.com> wrote:
>
> [Why&How]
> Expose a new debugfs enum to force a subviewport memory clock switch
> to facilitate easy testing.
>

Is the debugfs support already plumbed in and this just enables you to
use it?  If it's in debugfs, do we really need a module parameter to
enable it or can it just be enabled by default and used via debugfs
when needed?

Alex

> Signed-off-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 +++
>  drivers/gpu/drm/amd/include/amd_shared.h          | 1 +
>  2 files changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index c9145864ed2b..7a034ca95be2 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -1559,6 +1559,9 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
>         if (amdgpu_dc_debug_mask & DC_DISABLE_CLOCK_GATING)
>                 adev->dm.dc->debug.disable_clock_gate = true;
>
> +       if (amdgpu_dc_debug_mask & DC_FORCE_SUBVP_MCLK_SWITCH)
> +               adev->dm.dc->debug.force_subvp_mclk_switch = true;
> +
>         r = dm_dmub_hw_init(adev);
>         if (r) {
>                 DRM_ERROR("DMUB interface failed to initialize: status=%d\n", r);
> diff --git a/drivers/gpu/drm/amd/include/amd_shared.h b/drivers/gpu/drm/amd/include/amd_shared.h
> index bcdf7453a403..b1c55dd7b498 100644
> --- a/drivers/gpu/drm/amd/include/amd_shared.h
> +++ b/drivers/gpu/drm/amd/include/amd_shared.h
> @@ -247,6 +247,7 @@ enum DC_DEBUG_MASK {
>         DC_DISABLE_DSC = 0x4,
>         DC_DISABLE_CLOCK_GATING = 0x8,
>         DC_DISABLE_PSR = 0x10,
> +       DC_FORCE_SUBVP_MCLK_SWITCH = 0x20,
>  };
>
>  enum amd_dpm_forced_level;
> --
> 2.36.1
>