[PATCH 6.9 345/374] drm/amdgpu: Adjust logic in amdgpu_device_partner_bandwidth()

Greg Kroah-Hartman
2024-06-06T14:11:17Z

From: Alex Deucher <alexander.deucher@amd.com>

[ Upstream commit ba46b3bda296c4f82b061ac40b90f49d2a00a380 ]

Use current speed/width on devices which don't support
dynamic PCIe switching.

Fixes: 466a7d115326 ("drm/amd: Use the first non-dGPU PCI device for BW limits")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3289
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 7753a2e64d411..941d6e379b8a6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -5809,13 +5809,18 @@ static void amdgpu_device_partner_bandwidth(struct amdgpu_device *adev,
*speed = PCI_SPEED_UNKNOWN;
*width = PCIE_LNK_WIDTH_UNKNOWN;

- while ((parent = pci_upstream_bridge(parent))) {
- /* skip upstream/downstream switches internal to dGPU*/
- if (parent->vendor == PCI_VENDOR_ID_ATI)
- continue;
- *speed = pcie_get_speed_cap(parent);
- *width = pcie_get_width_cap(parent);
- break;
+ if (amdgpu_device_pcie_dynamic_switching_supported(adev)) {
+ while ((parent = pci_upstream_bridge(parent))) {
+ /* skip upstream/downstream switches internal to dGPU*/
+ if (parent->vendor == PCI_VENDOR_ID_ATI)
+ continue;
+ *speed = pcie_get_speed_cap(parent);
+ *width = pcie_get_width_cap(parent);
+ break;
+ }
+ } else {
+ /* use the current speeds rather than max if switching is not supported */
+ pcie_bandwidth_available(adev->pdev, NULL, speed, width);
}
}

--
2.43.0