[PATCH] drm/amd: Forbid suspending into non-default suspend states

[Alex Deucher]

On Tue, Apr 8, 2025 at 2:10 PM Mario Limonciello <superm1 at kernel.org> wrote:
>
> From: Mario Limonciello <mario.limonciello at amd.com>
>
> On systems that default to 'deep' some userspace software likes
> to try to suspend in 'deep' first.  If there is a failure for any
> reason (such as -ENOMEM) the failure is ignored and then it will
> try to use 's2idle' as a fallback. This fails, but more importantly
> it leads to graphical problems.
>
> Forbid this behavior and only allow suspending in the last state
> supported by the system.
>
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4093
> Signed-off-by: Mario Limonciello <mario.limonciello at amd.com>

Acked-by: Alex Deucher <alexander.deucher at amd.com>

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu.h     |  1 +
>  drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 14 +++++++++++++-
>  2 files changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index 6d83ccfa42eeb..d79fd557b2d6c 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -1124,6 +1124,7 @@ struct amdgpu_device {
>         bool                            in_s3;
>         bool                            in_s4;
>         bool                            in_s0ix;
> +       suspend_state_t                 last_suspend_state;
>
>         enum pp_mp1_state               mp1_state;
>         struct amdgpu_doorbell_index doorbell_index;
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index 26bf896f1444e..24ee4710f807f 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -2548,8 +2548,20 @@ static int amdgpu_pmops_suspend(struct device *dev)
>                 adev->in_s0ix = true;
>         else if (amdgpu_acpi_is_s3_active(adev))
>                 adev->in_s3 = true;
> -       if (!adev->in_s0ix && !adev->in_s3)
> +       if (!adev->in_s0ix && !adev->in_s3) {
> +               /* don't allow going deep first time followed by s2idle the next time */
> +               if (adev->last_suspend_state != PM_SUSPEND_ON &&
> +                   adev->last_suspend_state != pm_suspend_target_state) {
> +                       drm_err_once(drm_dev, "Unsupported suspend state %d\n",
> +                                    pm_suspend_target_state);
> +                       return -EINVAL;
> +               }
>                 return 0;
> +       }
> +
> +       /* cache the state last used for suspend */
> +       adev->last_suspend_state = pm_suspend_target_state;
> +
>         return amdgpu_device_suspend(drm_dev, true);
>  }
>
> --
> 2.43.0
>