drm/amdkfd: Optimize out sdma doorbell array in kgd2kfd_shared_resources

We can directly calculate sdma doorbell indexes in the process doorbell
pages through the doorbell_index structure in amdgpu_device, so no need
to cache them in kgd2kfd_shared_resources any more. This alleviates the
adaptation needs when new SDMA configurations are introduced.
Signed-off-by: Yong Zhao <Yong.Zhao@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -131,7 +131,7 @@ static void amdgpu_doorbell_get_kfd_info(struct amdgpu_device *adev,
 
 void amdgpu_amdkfd_device_init(struct amdgpu_device *adev)
 {
-	int i, n;
+	int i;
 	int last_valid_bit;
 
 	if (adev->kfd.dev) {
@@ -142,7 +142,9 @@ void amdgpu_amdkfd_device_init(struct amdgpu_device *adev)
 			.gpuvm_size = min(adev->vm_manager.max_pfn
 					  << AMDGPU_GPU_PAGE_SHIFT,
 					  AMDGPU_GMC_HOLE_START),
-			.drm_render_minor = adev->ddev->render->index
+			.drm_render_minor = adev->ddev->render->index,
+			.sdma_doorbell_idx = adev->doorbell_index.sdma_engine,
+
 		};
 
 		/* this is going to have a few of the MSBs set that we need to
@@ -172,31 +174,6 @@ void amdgpu_amdkfd_device_init(struct amdgpu_device *adev)
 				&gpu_resources.doorbell_aperture_size,
 				&gpu_resources.doorbell_start_offset);
 
-		if (adev->asic_type < CHIP_VEGA10) {
-			kgd2kfd_device_init(adev->kfd.dev, &gpu_resources);
-			return;
-		}
-
-		n = (adev->asic_type < CHIP_VEGA20) ? 2 : 8;
-
-		for (i = 0; i < n; i += 2) {
-			/* On SOC15 the BIF is involved in routing
-			 * doorbells using the low 12 bits of the
-			 * address. Communicate the assignments to
-			 * KFD. KFD uses two doorbell pages per
-			 * process in case of 64-bit doorbells so we
-			 * can use each doorbell assignment twice.
-			 */
-			gpu_resources.sdma_doorbell[0][i] =
-				adev->doorbell_index.sdma_engine[0] + (i >> 1);
-			gpu_resources.sdma_doorbell[0][i+1] =
-				adev->doorbell_index.sdma_engine[0] + 0x200 + (i >> 1);
-			gpu_resources.sdma_doorbell[1][i] =
-				adev->doorbell_index.sdma_engine[1] + (i >> 1);
-			gpu_resources.sdma_doorbell[1][i+1] =
-				adev->doorbell_index.sdma_engine[1] + 0x200 + (i >> 1);
-		}
-
 		/* Since SOC15, BIF starts to statically use the
 		 * lower 12 bits of doorbell addresses for routing
 		 * based on settings in registers like
@@ -205,10 +182,12 @@ void amdgpu_amdkfd_device_init(struct amdgpu_device *adev)
 		 * 12 bits of its address has to be outside the range
 		 * set for SDMA, VCN, and IH blocks.
 		 */
+		if (adev->asic_type >= CHIP_VEGA10) {
 			gpu_resources.non_cp_doorbells_start =
 					adev->doorbell_index.first_non_cp;
 			gpu_resources.non_cp_doorbells_end =
 					adev->doorbell_index.last_non_cp;
+		}
 
 		kgd2kfd_device_init(adev->kfd.dev, &gpu_resources);
 	}

drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c

@@ -134,12 +134,18 @@ static int allocate_doorbell(struct qcm_process_device *qpd, struct queue *q)
 		 */
 		q->doorbell_id = q->properties.queue_id;
 	} else if (q->properties.type == KFD_QUEUE_TYPE_SDMA) {
-		/* For SDMA queues on SOC15, use static doorbell
-		 * assignments based on the engine and queue.
+		/* For SDMA queues on SOC15 with 8-byte doorbell, use static
+		 * doorbell assignments based on the engine and queue id.
+		 * The doobell index distance between RLC (2*i) and (2*i+1)
+		 * for a SDMA engine is 512.
 		 */
-		q->doorbell_id = dev->shared_resources.sdma_doorbell
-			[q->properties.sdma_engine_id]
-			[q->properties.sdma_queue_id];
+		uint32_t *idx_offset =
+				dev->shared_resources.sdma_doorbell_idx;
+
+		q->doorbell_id = idx_offset[q->properties.sdma_engine_id]
+			+ (q->properties.sdma_queue_id & 1)
+			* KFD_QUEUE_DOORBELL_MIRROR_OFFSET
+			+ (q->properties.sdma_queue_id >> 1);
 	} else {
 		/* For CP queues on SOC15 reserve a free doorbell ID */
 		unsigned int found;

drivers/gpu/drm/amd/include/kgd_kfd_interface.h

@@ -137,11 +137,11 @@ struct kgd2kfd_shared_resources {
 	/* Bit n == 1 means Queue n is available for KFD */
 	DECLARE_BITMAP(queue_bitmap, KGD_MAX_QUEUES);
 
-	/* Doorbell assignments (SOC15 and later chips only). Only
+	/* SDMA doorbell assignments (SOC15 and later chips only). Only
 	 * specific doorbells are routed to each SDMA engine. Others
 	 * are routed to IH and VCN. They are not usable by the CP.
 	 */
-	unsigned int sdma_doorbell[2][8];
+	uint32_t *sdma_doorbell_idx;
 
 	/* From SOC15 onward, the doorbell index range not usable for CP
 	 * queues.