drm/amdgpu: introduce a stolen reserved buffer to protect specific buffer region (v2)

Some ASICs such as Yellow Carp needs to reserve a region of video memory
to avoid access from driver. So this patch is to introduce a stolen
reserved buffer to protect specific buffer region.

v2: free this buffer in amdgpu_ttm_fini.

Signed-off-by: Huang Rui <ray.huang@amd.com>
Acked-and-Tested-by: Aaron Liu <aaron.liu@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
index 7061c4a0e421..86d28dca4f1d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
@@ -785,3 +785,19 @@ uint64_t amdgpu_gmc_vram_cpu_pa(struct amdgpu_device *adev, struct amdgpu_bo *bo
 {
 	return amdgpu_bo_gpu_offset(bo) - adev->gmc.vram_start + adev->gmc.aper_base;
 }
+
+void amdgpu_gmc_get_reserved_allocation(struct amdgpu_device *adev)
+{
+	/* Some ASICs need to reserve a region of video memory to avoid access
+	 * from driver */
+	switch (adev->asic_type) {
+	case CHIP_YELLOW_CARP:
+		adev->mman.stolen_reserved_offset = 0x1ffb0000;
+		adev->mman.stolen_reserved_size = 64 * PAGE_SIZE;
+		break;
+	default:
+		adev->mman.stolen_reserved_offset = 0;
+		adev->mman.stolen_reserved_size = 0;
+		break;
+	}
+}