[PATCH v2] drm/amd: Add pre-zen AMD hardware to PCIe dynamic switching exclusions

[Mario Limonciello]

From: Mario Limonciello <mario.limonciello at amd.com>

AMD RX580 when added AMD Phenom 2 has problems with overheating. This is due to
changes with PCIe dynamic switching introduced by commit 466a7d115326e
("drm/amd: Use the first non-dGPU PCI device for BW limits").

To avoid risks of other issues with old hardware require at least Zen hardware
for AMD side to enable PCIe dynamic switching.

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4098
Fixes: 466a7d115326e ("drm/amd: Use the first non-dGPU PCI device for BW limits")
Signed-off-by: Mario Limonciello <mario.limonciello at amd.com>
---
v2:
 * Cover more hardware
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index a30111d2c3ea0..caa44ee788c8f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -1854,6 +1854,9 @@ bool amdgpu_device_seamless_boot_supported(struct amdgpu_device *adev)
  *
  * https://edc.intel.com/content/www/us/en/design/products/platforms/details/raptor-lake-s/13th-generation-core-processors-datasheet-volume-1-of-2/005/pci-express-support/
  * https://gitlab.freedesktop.org/drm/amd/-/issues/2663
+ *
+ * AMD Phenom II X6 1090T has a similar issue
+ * https://gitlab.freedesktop.org/drm/amd/-/issues/4098
  */
 static bool amdgpu_device_pcie_dynamic_switching_supported(struct amdgpu_device *adev)
 {
@@ -1866,6 +1869,8 @@ static bool amdgpu_device_pcie_dynamic_switching_supported(struct amdgpu_device
 
 	if (c->x86_vendor == X86_VENDOR_INTEL)
 		return false;
+	if (c->x86_vendor == X86_VENDOR_AMD && !cpu_feature_enabled(X86_FEATURE_ZEN))
+		return false;
 #endif
 	return true;
 }
-- 
2.43.0