On 2025-03-06 13:51, Mario Limonciello wrote:
> When userspace invokes S4 the flow is:
>
> 1) amdgpu_pmops_prepare()
> 2) amdgpu_pmops_freeze()
> 3) Create hibernation image
> 4) amdgpu_pmops_thaw()
> 5) Write out image to disk
> 6) Turn off system
>
> Then on resume amdgpu_pmops_restore() is called.
>
> This flow has a problem that because amdgpu_pmops_thaw() is called
> it will call amdgpu_device_resume() which will resume all of the GPU.
>
> This includes turning the display hardware back on and discovering
> connectors again.
>
> This is an unexpected experience for the display to turn back on.
> Adjust the flow so that during the S4 sequence display hardware is
> not turned back on.
>
> Reported-by: Xaver Hugl <xaver.h...@gmail.com>
> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/2038
> Cc: Muhammad Usama Anjum <usama.an...@collabora.com>
> Signed-off-by: Mario Limonciello <mario.limoncie...@amd.com>
Acked-by: Harry Wentland <harry.wentl...@amd.com>
Harry
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 11 +++++++++--
> drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 +++++
> 2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index b161daa90019..b54c4b2f3f7f 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -2565,7 +2565,6 @@ static int amdgpu_pmops_freeze(struct device *dev)
> int r;
>
> r = amdgpu_device_suspend(drm_dev, true);
> - adev->in_s4 = false;
> if (r)
> return r;
>
> @@ -2577,8 +2576,13 @@ static int amdgpu_pmops_freeze(struct device *dev)
> static int amdgpu_pmops_thaw(struct device *dev)
> {
> struct drm_device *drm_dev = dev_get_drvdata(dev);
> + struct amdgpu_device *adev = drm_to_adev(drm_dev);
> + int r;
>
> - return amdgpu_device_resume(drm_dev, true);
> + r = amdgpu_device_resume(drm_dev, true);
> + adev->in_s4 = false;
> +
> + return r;
> }
>
> static int amdgpu_pmops_poweroff(struct device *dev)
> @@ -2591,6 +2595,9 @@ static int amdgpu_pmops_poweroff(struct device *dev)
> static int amdgpu_pmops_restore(struct device *dev)
> {
> struct drm_device *drm_dev = dev_get_drvdata(dev);
> + struct amdgpu_device *adev = drm_to_adev(drm_dev);
> +
> + adev->in_s4 = false;
>
> return amdgpu_device_resume(drm_dev, true);
> }
> 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 6f9331fe91c3..5939796db74c 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -3431,6 +3431,11 @@ static int dm_resume(struct amdgpu_ip_block *ip_block)
>
> return 0;
> }
> +
> + /* leave display off for S4 sequence */
> + if (adev->in_s4)
> + return 0;
> +
> /* Recreate dc_state - DC invalidates it when setting power state to
> S3. */
> dc_state_release(dm_state->context);
> dm_state->context = dc_state_create(dm->dc, NULL);
