On 2025/7/10 12:18, Lazar, Lijo wrote:
On 7/10/2025 1:20 AM, Mario Limonciello wrote:
On 7/9/2025 6:05 AM, Samuel Zhang wrote:
For normal hibernation, GPU do not need to be resumed in thaw since it is
not involved in writing the hibernation image. Skip resume in this case
can reduce the hibernation time.
On VM with 8 * 192GB VRAM dGPUs, 98% VRAM usage and 1.7TB system memory,
this can save 50 minutes.
Signed-off-by: Samuel Zhang <guoqing.zh...@amd.com>
I hand modified the patches for other changes missing from linux-next in
your base.
I checked on an APU with an eDP display connected and from a VT
hibernate does keep the display off now so this is definitely an
improvement there too.
Tested-by: Mario Limonciello <mario.limoncie...@amd.com>
Thank you, Mario!
---
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/
drm/amd/amdgpu/amdgpu_drv.c
index 4f8632737574..b24c420983ef 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -2541,6 +2541,10 @@ amdgpu_pci_shutdown(struct pci_dev *pdev)
if (amdgpu_ras_intr_triggered())
return;
+ /* device maybe not resumed here, return immediately in this
case */
+ if (adev->in_s4 && adev->in_suspend)
+ return;
+
/* if we are running in a VM, make sure the device
* torn down properly on reboot/shutdown.
* unfortunately we can't detect certain
@@ -2557,6 +2561,10 @@ 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);
+ /* device maybe not resumed here, return immediately in this
case */
+ if (adev->in_s4 && adev->in_suspend)
+ return 0;
+
Is this one right? Don't we still want to call prepare() for all the HW
IP blocks? The eviction call that happens in prepare() is a no-op but
there are other IP blocks with an prepare_suspend() callback like DCN.
That is I think you're destroying the optimization from commit
50e0bae34fa6b ("drm/amd/display: Add and use new dm_prepare_suspend()
callback") by adding this code here.
I guess this takes care of the prepare() before a power_off(). For the
hibernate prepare() call, in_suspend flag will remain false and it
should get executed. If the device is runtime-suspended already, then
the path won't be taken. Assuming that's fine.
Thanks,
Lijo
That's right. Thank you for the clarification, Lijo.
Rafael reminded me yesterday that there are 2 hibernation mode, controlled by
`/sys/power/disk`.
The 2 mode will call different callbacks after saving the image:
shutdown mode, hibernate will go through following steps:
1. amdgpu_pmops_prepare
2. amdgpu_pmops_freeze
3. create image
4. amdgpu_pmops_thaw
5. amdgpu_pmops_complete
6. save image
7. amdgpu_pci_shutdown
platform mode, hibernate will go through following steps:
1. amdgpu_pmops_prepare
2. amdgpu_pmops_freeze
3. create image
4. amdgpu_pmops_thaw
5. amdgpu_pmops_complete
6. save image
7. amdgpu_pmops_prepare
8. amdgpu_pmops_poweroff
This code is just to skip the step 7 of platform mode hibernation,
prepare to power off.
adev->in_suspend is false in step 2, so it will not return in new the check.
adev->in_suspend is true in step 7, it will return in new the check.
Regards
Sam
/* Return a positive number here so
* DPM_FLAG_SMART_SUSPEND works properly
*/
@@ -2655,12 +2663,21 @@ static int amdgpu_pmops_thaw(struct device *dev)
{
struct drm_device *drm_dev = dev_get_drvdata(dev);
+ /* do not resume device if it's normal hibernation */
+ if (!pm_hibernate_is_recovering())
+ return 0;
+
return amdgpu_device_resume(drm_dev, true);
}
static int amdgpu_pmops_poweroff(struct device *dev)
{
struct drm_device *drm_dev = dev_get_drvdata(dev);
+ struct amdgpu_device *adev = drm_to_adev(drm_dev);
+
+ /* device maybe not resumed here, return immediately in this case */
+ if (adev->in_s4 && adev->in_suspend)
+ return 0;
return amdgpu_device_suspend(drm_dev, true);
}
