On Wed, Feb 7, 2024 at 3:48 PM Mario Limonciello
<mario.limonciello@xxxxxxx> wrote:
>
> commit 5095d5418193 ("drm/amd: Evict resources during PM ops prepare() callback")
> intentionally moved the eviction of resources to earlier in the suspend
> process, but this introduced a subtle change that it occurs before adev->in_s0ix
> or adev->in_s3 are set. This meant that APUs actually started to evict
> resources at suspend time as well.
>
> Add a new `in_prepare` flag that is set for the life of the prepare() callback
> to return the old code flow. Drop the existing call to return 1 in this case because
> the suspend() callback looks for the flags too.
>
> Also, introduce a new amdgpu_device_freeze() function to call at S4 and evict
> resources in this callback so that APUs will still get resources evicted.
>
> Reported-by: Jürg Billeter <j@xxxxxxxxx>
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3132#note_2271038
> Fixes: 5095d5418193 ("drm/amd: Evict resources during PM ops prepare() callback")
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> ---
> v1->v2:
> * Add and use new in_prepare member
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu.h | 4 +-
> drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 46 ++++++++++++++++++++--
> drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 21 ++--------
> 3 files changed, 48 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index 5d5be3e20687..f9db09a9017a 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -1075,7 +1075,8 @@ struct amdgpu_device {
> u8 reset_magic[AMDGPU_RESET_MAGIC_NUM];
>
> /* s3/s4 mask */
> - bool in_suspend;
> + bool in_prepare;
> + bool in_suspend;
> bool in_s3;
> bool in_s4;
> bool in_s0ix;
> @@ -1462,6 +1463,7 @@ int amdgpu_device_ip_suspend(struct amdgpu_device *adev);
> int amdgpu_device_prepare(struct drm_device *dev);
> int amdgpu_device_suspend(struct drm_device *dev, bool fbcon);
> int amdgpu_device_resume(struct drm_device *dev, bool fbcon);
> +int amdgpu_device_freeze(struct drm_device *drm_dev);
> u32 amdgpu_get_vblank_counter_kms(struct drm_crtc *crtc);
> int amdgpu_enable_vblank_kms(struct drm_crtc *crtc);
> void amdgpu_disable_vblank_kms(struct drm_crtc *crtc);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 2bc460cb993d..0a337fcd89b4 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -4492,7 +4492,7 @@ static int amdgpu_device_evict_resources(struct amdgpu_device *adev)
> int ret;
>
> /* No need to evict vram on APUs for suspend to ram or s2idle */
> - if ((adev->in_s3 || adev->in_s0ix) && (adev->flags & AMD_IS_APU))
> + if ((adev->in_prepare) && (adev->flags & AMD_IS_APU))
Could probably simplify this to:
if ((!adev->in_s4) && (adev->flags & AMD_IS_APU))
Then you could drop the in_prepare variable.
> return 0;
>
> ret = amdgpu_ttm_evict_resources(adev, TTM_PL_VRAM);
> @@ -4521,10 +4521,12 @@ int amdgpu_device_prepare(struct drm_device *dev)
> if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
> return 0;
>
> + adev->in_prepare = true;
> +
> /* Evict the majority of BOs before starting suspend sequence */
> r = amdgpu_device_evict_resources(adev);
> if (r)
> - return r;
> + goto unprepare;
>
> for (i = 0; i < adev->num_ip_blocks; i++) {
> if (!adev->ip_blocks[i].status.valid)
> @@ -4533,10 +4535,46 @@ int amdgpu_device_prepare(struct drm_device *dev)
> continue;
> r = adev->ip_blocks[i].version->funcs->prepare_suspend((void *)adev);
> if (r)
> - return r;
> + goto unprepare;
> }
>
> - return 0;
> +unprepare:
> + adev->in_prepare = FALSE;
> +
> + return r;
> +}
> +
> +/**
> + * amdgpu_device_freeze - run S4 sequence
> + *
> + * @dev: drm dev pointer
> + *
> + * Prepare to put the hw in the S4 state (all asics).
> + * Returns 0 for success or an error on failure.
> + * Called at driver freeze.
> + */
> +int amdgpu_device_freeze(struct drm_device *drm_dev)
> +{
> + struct amdgpu_device *adev = drm_to_adev(drm_dev);
> + int r;
> +
> + adev->in_s4 = true;
> +
> + r = amdgpu_device_evict_resources(adev);
Won't this be too late to allocate memory? Doesn't this need to
happen in prepare() even for S4?
Alex
> + if (r)
> + goto cleanup;
> +
> + r = amdgpu_device_suspend(drm_dev, true);
> + if (r)
> + goto cleanup;
> +
> + if (amdgpu_acpi_should_gpu_reset(adev))
> + r = amdgpu_asic_reset(adev);
> +
> +cleanup:
> + adev->in_s4 = false;
> +
> + return r;
> }
>
> /**
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index b74f68a15802..fc9caa14c9d6 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -2456,6 +2456,7 @@ static int amdgpu_pmops_prepare(struct device *dev)
> {
> struct drm_device *drm_dev = dev_get_drvdata(dev);
> struct amdgpu_device *adev = drm_to_adev(drm_dev);
> + int r;
>
> /* Return a positive number here so
> * DPM_FLAG_SMART_SUSPEND works properly
> @@ -2464,13 +2465,6 @@ static int amdgpu_pmops_prepare(struct device *dev)
> pm_runtime_suspended(dev))
> return 1;
>
> - /* if we will not support s3 or s2i for the device
> - * then skip suspend
> - */
> - if (!amdgpu_acpi_is_s0ix_active(adev) &&
> - !amdgpu_acpi_is_s3_active(adev))
> - return 1;
> -
> return amdgpu_device_prepare(drm_dev);
> }
>
> @@ -2488,6 +2482,7 @@ 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)
> return 0;
> return amdgpu_device_suspend(drm_dev, true);
> @@ -2528,18 +2523,8 @@ static int amdgpu_pmops_resume(struct device *dev)
> static int amdgpu_pmops_freeze(struct device *dev)
> {
> struct drm_device *drm_dev = dev_get_drvdata(dev);
> - struct amdgpu_device *adev = drm_to_adev(drm_dev);
> - int r;
> -
> - adev->in_s4 = true;
> - r = amdgpu_device_suspend(drm_dev, true);
> - adev->in_s4 = false;
> - if (r)
> - return r;
>
> - if (amdgpu_acpi_should_gpu_reset(adev))
> - return amdgpu_asic_reset(adev);
> - return 0;
> + return amdgpu_device_freeze(drm_dev);
> }
>
> static int amdgpu_pmops_thaw(struct device *dev)
> --
> 2.34.1
>
