AMD General Reviewed-by: Kenneth Feng <[email protected]>
-----Original Message----- From: Wang, Yang(Kevin) <[email protected]> Sent: Wednesday, August 12, 2026 4:09 PM To: [email protected] Cc: Deucher, Alexander <[email protected]>; Zhang, Hawking <[email protected]>; Feng, Kenneth <[email protected]>; Li, Candice <[email protected]> Subject: [PATCH] drm/amdgpu: Disable runtime PM for externally attached dGPUs pci_is_thunderbolt_attached() requires an upstream PCI bridge with is_thunderbolt set from an Intel Thunderbolt VSEC. This does not cover the affected ASM4242 USB4 PCI hierarchy: 00:02.2 \- 0f:00.0 [1b21:2421] +- 10:01.0 [1b21:2423] -> 45:00.0 -> 46:00.0 | -> 47:00.0 -> 48:00.0 -> 49:00.0 [1002:7590] \- 10:03.0 -> 76:00.0 [1b21:2425] USB4 Host Router The host router is outside the GPU upstream bridge chain, leaving no ancestor with is_thunderbolt set. PCI core propagates DEVICE_REMOVABLE below the external-facing PCIe tunnel. Disable Runtime PM when either pci_is_thunderbolt_attached() or dev_is_removable() is true. Signed-off-by: Yang Wang <[email protected]> --- drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c index 8ebe24d59ab6..a4b4f9645c84 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -609,6 +609,13 @@ void amdgpu_device_detect_runtime_pm_mode(struct amdgpu_device *adev) int bamaco_support; adev->pm.rpm_mode = AMDGPU_RUNPM_NONE; + if (pci_is_thunderbolt_attached(adev->pdev) || + dev_is_removable(&adev->pdev->dev)) { + dev_info(adev->dev, + "Runtime PM disabled for externally attached device\n"); + return; + } + bamaco_support = amdgpu_device_supports_baco(adev); switch (amdgpu_runtime_pm) { -- 2.54.0
