On Fri, May 21, 2021 at 4:14 PM Andrey Grodzovsky andrey.grodzovsky@amd.com wrote:
Problem: When device goes into sleep state due to prolonged innactivity (e.g. BACO sleep) and then hot unplugged, PCI core will try to wake up the device as part of unplug process. Since the device is gone all HW programming during rpm resume fails leading to a bad SW state later during pci remove handling.
Fix: Use a flag we use for PCIe error recovery to avoid accessing registres. This allows to succefully complete rpm resume sequence and finish pci remove.
Might make sense to create a preliminary patch to change the name of this flag to something like no_hw_access since it's not specific to pci error handling.
Alex
P.S Must use pci_device_is_present and not drm_dev_enter/exit here since rpm resume happens before PCI remove and so the unplug flag is not set yet.
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1081 Signed-off-by: Andrey Grodzovsky andrey.grodzovsky@amd.com
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c index d8db5929cdd9..ab95ebf56636 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -1555,6 +1555,11 @@ static int amdgpu_pmops_runtime_resume(struct device *dev) if (!adev->runpm) return -EINVAL;
/* Avoids registers access if device is physically gone */if (!pci_device_is_present(adev->pdev))adev->in_pci_err_recovery = true;if (amdgpu_device_supports_px(drm_dev)) { drm_dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;-- 2.25.1