drm/amdgpu/vcn:Set VCPU busy after gate power during vcn SPG start

Set VCPU busy after gate power during vcn Static Power Gate start
Signed-off-by: James Zhu <James.Zhu@amd.com>
Acked-by: Leo Liu <leo.liu@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/vcn_v1_0.c

@@ -777,6 +777,10 @@ static int vcn_v1_0_start_spg_mode(struct amdgpu_device *adev)
 	lmi_swap_cntl = 0;
 
 	vcn_1_0_disable_static_power_gating(adev);
+
+	tmp = RREG32_SOC15(UVD, 0, mmUVD_STATUS) | UVD_STATUS__UVD_BUSY;
+	WREG32_SOC15(UVD, 0, mmUVD_STATUS, tmp);
+
 	/* disable clock gating */
 	vcn_v1_0_disable_clock_gating(adev);