drm/amdgpu/sdma: allocate CSA per sdma ring

Allocate CSA for the given sdma ring.
Acked-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Jack Xiao <Jack.Xiao@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c

@@ -24,6 +24,10 @@
 #include "amdgpu.h"
 #include "amdgpu_sdma.h"
 
+#define AMDGPU_CSA_SDMA_SIZE 64
+/* SDMA CSA reside in the 3rd page of CSA */
+#define AMDGPU_CSA_SDMA_OFFSET (4096 * 2)
+
 /*
  * GPU SDMA IP block helpers function.
  */
@@ -56,3 +60,26 @@ int amdgpu_sdma_get_index_from_ring(struct amdgpu_ring *ring, uint32_t *index)
 
 	return -EINVAL;
 }
+
+uint64_t amdgpu_sdma_get_csa_mc_addr(struct amdgpu_ring *ring,
+				     unsigned vmid)
+{
+	struct amdgpu_device *adev = ring->adev;
+	uint64_t csa_mc_addr;
+	uint32_t index = 0;
+	int r;
+
+	if (vmid == 0 || !amdgpu_mcbp)
+		return 0;
+
+	r = amdgpu_sdma_get_index_from_ring(ring, &index);
+
+	if (r || index > 31)
+		csa_mc_addr = 0;
+	else
+		csa_mc_addr = amdgpu_csa_vaddr(adev) +
+			AMDGPU_CSA_SDMA_OFFSET +
+			index * AMDGPU_CSA_SDMA_SIZE;
+
+	return csa_mc_addr;
+}

drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.h

@@ -97,5 +97,5 @@ struct amdgpu_buffer_funcs {
 struct amdgpu_sdma_instance *
 amdgpu_sdma_get_instance_from_ring(struct amdgpu_ring *ring);
 int amdgpu_sdma_get_index_from_ring(struct amdgpu_ring *ring, uint32_t *index);
-
+uint64_t amdgpu_sdma_get_csa_mc_addr(struct amdgpu_ring *ring, unsigned vmid);
 #endif