drm/amdgpu/vcn: add shared memory restore after wake up from sleep.

VCN shared memory needs restore after wake up during S3 test.

v2: Allocate shared memory saved_bo at sw_init and free it in sw_fini.
Signed-off-by: James Zhu <James.Zhu@amd.com>
Reviewed-by: Feifei Xu <Feifei.Xu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -56,7 +56,7 @@ static void amdgpu_vcn_idle_work_handler(struct work_struct *work);
 
 int amdgpu_vcn_sw_init(struct amdgpu_device *adev)
 {
-	unsigned long bo_size;
+	unsigned long bo_size, fw_shared_bo_size;
 	const char *fw_name;
 	const struct common_firmware_header *hdr;
 	unsigned char fw_check;
@@ -190,6 +190,9 @@ int amdgpu_vcn_sw_init(struct amdgpu_device *adev)
 			dev_err(adev->dev, "VCN %d (%d) failed to allocate firmware shared bo\n", i, r);
 			return r;
 		}
+
+		fw_shared_bo_size = amdgpu_bo_size(adev->vcn.inst[i].fw_shared_bo);
+		adev->vcn.inst[i].saved_shm_bo = kvmalloc(fw_shared_bo_size, GFP_KERNEL);
 	}
 
 	return 0;
@@ -205,6 +208,7 @@ int amdgpu_vcn_sw_fini(struct amdgpu_device *adev)
 		if (adev->vcn.harvest_config & (1 << j))
 			continue;
 
+		kvfree(adev->vcn.inst[j].saved_shm_bo);
 		amdgpu_bo_free_kernel(&adev->vcn.inst[j].fw_shared_bo,
 					  &adev->vcn.inst[j].fw_shared_gpu_addr,
 					  (void **)&adev->vcn.inst[j].fw_shared_cpu_addr);
@@ -254,6 +258,17 @@ int amdgpu_vcn_suspend(struct amdgpu_device *adev)
 			return -ENOMEM;
 
 		memcpy_fromio(adev->vcn.inst[i].saved_bo, ptr, size);
+
+		if (adev->vcn.inst[i].fw_shared_bo == NULL)
+			return 0;
+
+		if (!adev->vcn.inst[i].saved_shm_bo)
+			return -ENOMEM;
+
+		size = amdgpu_bo_size(adev->vcn.inst[i].fw_shared_bo);
+		ptr = adev->vcn.inst[i].fw_shared_cpu_addr;
+
+		memcpy_fromio(adev->vcn.inst[i].saved_shm_bo, ptr, size);
 	}
 	return 0;
 }
@@ -291,6 +306,17 @@ int amdgpu_vcn_resume(struct amdgpu_device *adev)
 			}
 			memset_io(ptr, 0, size);
 		}
+
+		if (adev->vcn.inst[i].fw_shared_bo == NULL)
+			return -EINVAL;
+
+		size = amdgpu_bo_size(adev->vcn.inst[i].fw_shared_bo);
+		ptr = adev->vcn.inst[i].fw_shared_cpu_addr;
+
+		if (adev->vcn.inst[i].saved_shm_bo != NULL)
+			memcpy_toio(ptr, adev->vcn.inst[i].saved_shm_bo, size);
+		else
+			memset_io(ptr, 0, size);
 	}
 	return 0;
 }

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

@@ -194,6 +194,7 @@ struct amdgpu_vcn_inst {
 	atomic_t		dpg_enc_submission_cnt;
 	void			*fw_shared_cpu_addr;
 	uint64_t		fw_shared_gpu_addr;
+	void			*saved_shm_bo;
 };
 
 struct amdgpu_vcn {