[PATCH 4.9 12/86] drm/amdgpu: Notify sbios device ready before send request

Greg Kroah-Hartman
2018-03-16T15:31:38Z

From: Rex Zhu <Rex.Zhu@amd.com>

commit 1bced75f4ab04bec55aecb57d99435dc6d0ae5a0 upstream.

it is required if a platform supports PCIe root complex
core voltage reduction. After receiving this notification,
SBIOS can apply default PCIe root complex power policy.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_acpi.c
@@ -540,6 +540,9 @@ int amdgpu_acpi_pcie_performance_request
size_t size;
u32 retry = 3;

+ if (amdgpu_acpi_pcie_notify_device_ready(adev))
+ return -EINVAL;
+
/* Get the device handle */
handle = ACPI_HANDLE(&adev->pdev->dev);
if (!handle)