[PATCH 4/5] drm/radeon: Don't register Thunderbolt eGPU with vga_switcheroo

Lukas Wunner lukas at wunner.de
Fri Feb 24 19:19:45 UTC 2017


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.

Cc: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Lukas Wunner <lukas at wunner.de>
---
 drivers/gpu/drm/radeon/radeon_device.c | 7 +++++--
 drivers/gpu/drm/radeon/radeon_kms.c    | 3 ++-
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 4b0c388be3f5..27be17f0b227 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -1471,7 +1471,9 @@ int radeon_device_init(struct radeon_device *rdev,
 
 	if (rdev->flags & RADEON_IS_PX)
 		runtime = true;
-	vga_switcheroo_register_client(rdev->pdev, &radeon_switcheroo_ops, runtime);
+	if (!pci_is_thunderbolt_attached(rdev->pdev))
+		vga_switcheroo_register_client(rdev->pdev,
+					       &radeon_switcheroo_ops, runtime);
 	if (runtime)
 		vga_switcheroo_init_domain_pm_ops(rdev->dev, &rdev->vga_pm_domain);
 
@@ -1564,7 +1566,8 @@ void radeon_device_fini(struct radeon_device *rdev)
 	/* evict vram memory */
 	radeon_bo_evict_vram(rdev);
 	radeon_fini(rdev);
-	vga_switcheroo_unregister_client(rdev->pdev);
+	if (!pci_is_thunderbolt_attached(rdev->pdev))
+		vga_switcheroo_unregister_client(rdev->pdev);
 	if (rdev->flags & RADEON_IS_PX)
 		vga_switcheroo_fini_domain_pm_ops(rdev->dev);
 	vga_client_register(rdev->pdev, NULL, NULL, NULL);
diff --git a/drivers/gpu/drm/radeon/radeon_kms.c b/drivers/gpu/drm/radeon/radeon_kms.c
index 56f35c06742c..e95ceec1c97a 100644
--- a/drivers/gpu/drm/radeon/radeon_kms.c
+++ b/drivers/gpu/drm/radeon/radeon_kms.c
@@ -115,7 +115,8 @@ int radeon_driver_load_kms(struct drm_device *dev, unsigned long flags)
 
 	if ((radeon_runtime_pm != 0) &&
 	    radeon_has_atpx() &&
-	    ((flags & RADEON_IS_IGP) == 0))
+	    ((flags & RADEON_IS_IGP) == 0) &&
+	    !pci_is_thunderbolt_attached(rdev->pdev))
 		flags |= RADEON_IS_PX;
 
 	/* radeon_device_init should report only fatal error
-- 
2.11.0



More information about the amd-gfx mailing list