drm/amdgpu: Don't register Thunderbolt eGPU with vga_switcheroo
An external Thunderbolt GPU can neither drive the laptop's panel nor be
powered off by the platform, so there's no point in registering it with
vga_switcheroo. In fact, when the external GPU is runtime suspended,
vga_switcheroo will cut power to the internal discrete GPU, resulting in
a lockup. Moreover AMD's Windows driver special-cases Thunderbolt as
well.
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: http://patchwork.freedesktop.org/patch/msgid/701a8e89ce8ac39734736ab779558b6a4042a19e.1489145162.git.lukas@wunner.de
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index a3a105e..2996549 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -1763,7 +1763,9 @@
runtime = true;
if (amdgpu_device_is_px(ddev))
runtime = true;
- vga_switcheroo_register_client(adev->pdev, &amdgpu_switcheroo_ops, runtime);
+ if (!pci_is_thunderbolt_attached(adev->pdev))
+ vga_switcheroo_register_client(adev->pdev,
+ &amdgpu_switcheroo_ops, runtime);
if (runtime)
vga_switcheroo_init_domain_pm_ops(adev->dev, &adev->vga_pm_domain);
@@ -1926,7 +1928,8 @@
amdgpu_atombios_fini(adev);
kfree(adev->bios);
adev->bios = NULL;
- vga_switcheroo_unregister_client(adev->pdev);
+ if (!pci_is_thunderbolt_attached(adev->pdev))
+ vga_switcheroo_unregister_client(adev->pdev);
if (adev->flags & AMD_IS_PX)
vga_switcheroo_fini_domain_pm_ops(adev->dev);
vga_client_register(adev->pdev, NULL, NULL, NULL);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
index 61d94c7..2f3b236 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -103,7 +103,8 @@
amdgpu_has_atpx() &&
(amdgpu_is_atpx_hybrid() ||
amdgpu_has_atpx_dgpu_power_cntl()) &&
- ((flags & AMD_IS_APU) == 0))
+ ((flags & AMD_IS_APU) == 0) &&
+ !pci_is_thunderbolt_attached(dev->pdev))
flags |= AMD_IS_PX;
/* amdgpu_device_init should report only fatal error