From 869cedef57bb5c0e345222e23927bf421a0ed251 Mon Sep 17 00:00:00 2001 From: Jay Cornwall Date: Fri, 28 Aug 2015 11:25:39 -0500 Subject: [PATCH 0820/4131] drm/amdgpu: Enable BIF 5.0 atomic promotion to PCIe 3.0 AtomicOps Atomic operations to system memory are normally dropped by the BIF. Some PCIe 3.0 platforms support atomic routing to the host for execution by the CPU. To use this feature, atomic requests must be enabled in the GPU's PCIe configuration space. This is a no-op on platforms which cannot route the atomic request to the host. In this instance, atomics would be dropped with or without this change. Signed-off-by: Jay Cornwall Reviewed-by: Alex Deucher Acked-by: John Bridgman Conflicts: drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c Change-Id: I69f0b9b616ce4b1e7e09f069cc10a110d49d7c64 --- drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c index 3b3326d..7a29674 100644 --- a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c @@ -1136,6 +1136,10 @@ static int gmc_v8_0_sw_init(void *handle) adev->vm_manager.vram_base_offset = 0; } + /* Allow BIF to recode atomics to PCIe 3.0 AtomicOps. + */ + pci_enable_atomic_request(adev->pdev); + return 0; } -- 2.7.4