Patch "drm/amdgpu: register a vga_switcheroo client for MacBooks with apple-gmux" has been added to the 6.2-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drm/amdgpu: register a vga_switcheroo client for MacBooks with apple-gmux

to the 6.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-amdgpu-register-a-vga_switcheroo-client-for-macb.patch
and it can be found in the queue-6.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 9e2ad25cb7e899a22a9ae8b1a8c3f1be669d1614
Author: Orlando Chamberlain <orlandoch.dev@xxxxxxxxx>
Date:   Fri Mar 3 22:34:25 2023 +1100

    drm/amdgpu: register a vga_switcheroo client for MacBooks with apple-gmux
    
    [ Upstream commit d37a3929ca0363ed1dce02b2772cd5bc547ca66d ]
    
    Commit 3840c5bcc245 ("drm/amdgpu: disentangle runtime pm and
    vga_switcheroo") made amdgpu only register a vga_switcheroo client for
    GPU's with PX, however AMD GPUs in dual gpu Apple Macbooks do need to
    register, but don't have PX. Instead of AMD's PX, they use apple-gmux.
    
    Use apple_gmux_detect() to identify these gpus, and
    pci_is_thunderbolt_attached() to ensure eGPUs connected to Dual GPU
    Macbooks don't register with vga_switcheroo.
    
    Fixes: 3840c5bcc245 ("drm/amdgpu: disentangle runtime pm and vga_switcheroo")
    Link: https://lore.kernel.org/amd-gfx/20230210044826.9834-10-orlandoch.dev@xxxxxxxxx/
    Signed-off-by: Orlando Chamberlain <orlandoch.dev@xxxxxxxxx>
    Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 3dac1e139c5f3..533263d442657 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -35,6 +35,7 @@
 #include <linux/devcoredump.h>
 #include <generated/utsrelease.h>
 #include <linux/pci-p2pdma.h>
+#include <linux/apple-gmux.h>
 
 #include <drm/drm_aperture.h>
 #include <drm/drm_atomic_helper.h>
@@ -3952,12 +3953,15 @@ int amdgpu_device_init(struct amdgpu_device *adev,
 	if ((adev->pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA)
 		vga_client_register(adev->pdev, amdgpu_device_vga_set_decode);
 
-	if (amdgpu_device_supports_px(ddev)) {
-		px = true;
+	px = amdgpu_device_supports_px(ddev);
+
+	if (px || (!pci_is_thunderbolt_attached(adev->pdev) &&
+				apple_gmux_detect(NULL, NULL)))
 		vga_switcheroo_register_client(adev->pdev,
 					       &amdgpu_switcheroo_ops, px);
+
+	if (px)
 		vga_switcheroo_init_domain_pm_ops(adev->dev, &adev->vga_pm_domain);
-	}
 
 	if (adev->gmc.xgmi.pending_reset)
 		queue_delayed_work(system_wq, &mgpu_info.delayed_reset_work,
@@ -4063,6 +4067,7 @@ void amdgpu_device_fini_hw(struct amdgpu_device *adev)
 void amdgpu_device_fini_sw(struct amdgpu_device *adev)
 {
 	int idx;
+	bool px;
 
 	amdgpu_fence_driver_sw_fini(adev);
 	amdgpu_device_ip_fini(adev);
@@ -4082,10 +4087,16 @@ void amdgpu_device_fini_sw(struct amdgpu_device *adev)
 
 	kfree(adev->bios);
 	adev->bios = NULL;
-	if (amdgpu_device_supports_px(adev_to_drm(adev))) {
+
+	px = amdgpu_device_supports_px(adev_to_drm(adev));
+
+	if (px || (!pci_is_thunderbolt_attached(adev->pdev) &&
+				apple_gmux_detect(NULL, NULL)))
 		vga_switcheroo_unregister_client(adev->pdev);
+
+	if (px)
 		vga_switcheroo_fini_domain_pm_ops(adev->dev);
-	}
+
 	if ((adev->pdev->class >> 8) == PCI_CLASS_DISPLAY_VGA)
 		vga_client_unregister(adev->pdev);