From cd647796ac1334acec0468fae49a0dacbba2a34c Mon Sep 17 00:00:00 2001 From: Pierre-Eric Pelloux-Prayer Date: Thu, 24 Sep 2026 09:37:28 +0200 Subject: [PATCH] drm/amdgpu: implement workaround for sdma dcc corruption MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit For unknown reasons, on gfx12 using multiple entities can causes random corruption of BOs with DCC. This workaround seems to prevent the issue until the root cause is understood and fixed. Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/5663 Fixes: 3a6f6eeb3db5 ("drm/amdgpu: give ttm entities access to all the sdma scheds") Signed-off-by: Pierre-Eric Pelloux-Prayer Reviewed-by: Alex Deucher Reviewed-by: Christian König Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index c509dc45ba19..a3777ceb638f 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -2367,7 +2367,7 @@ void amdgpu_ttm_fini(struct amdgpu_device *adev) void amdgpu_ttm_enable_buffer_funcs(struct amdgpu_device *adev) { struct ttm_resource_manager *man = ttm_manager_type(&adev->mman.bdev, TTM_PL_VRAM); - u32 num_clear_entities, num_move_entities; + u32 num_clear_entities, num_move_entities, sdma_ip_version; int r, i, j; if (!adev->mman.initialized || amdgpu_in_reset(adev) || @@ -2392,6 +2392,12 @@ void amdgpu_ttm_enable_buffer_funcs(struct amdgpu_device *adev) num_clear_entities = MIN(adev->mman.num_buffer_funcs_scheds, TTM_NUM_MOVE_FENCES); num_move_entities = MIN(adev->mman.num_buffer_funcs_scheds, TTM_NUM_MOVE_FENCES); + /* TODO: workaround for DCC corruption when moving BOs from multiple queues at + * the same time: use a single queue until the root cause is identified and fixed. + */ + sdma_ip_version = amdgpu_ip_version(adev, SDMA0_HWIP, 0); + if (sdma_ip_version == IP_VERSION(7, 0, 0) || sdma_ip_version == IP_VERSION(7, 0, 1)) + num_move_entities = 1; adev->mman.clear_entities = kzalloc_objs(struct amdgpu_ttm_buffer_entity, num_clear_entities);