drm/amdgpu: add VCN function in NBIO v7.7

Add function to support VCN_4_0_2 doorbell
Signed-off-by: Sonny Jiang <sonny.jiang@amd.com>
Reviewed-by: James Zhu <James.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/nbio_v7_7.c

@@ -83,6 +83,26 @@ static void nbio_v7_7_sdma_doorbell_range(struct amdgpu_device *adev, int instan
 	WREG32_PCIE_PORT(reg, doorbell_range);
 }
 
+static void nbio_v7_7_vcn_doorbell_range(struct amdgpu_device *adev, bool use_doorbell,
+					int doorbell_index, int instance)
+{
+	u32 reg = SOC15_REG_OFFSET(NBIO, 0, regGDC0_BIF_VCN0_DOORBELL_RANGE);
+	u32 doorbell_range = RREG32_PCIE_PORT(reg);
+
+	if (use_doorbell) {
+		doorbell_range = REG_SET_FIELD(doorbell_range,
+					       GDC0_BIF_VCN0_DOORBELL_RANGE, OFFSET,
+					       doorbell_index);
+		doorbell_range = REG_SET_FIELD(doorbell_range,
+					       GDC0_BIF_VCN0_DOORBELL_RANGE, SIZE, 8);
+	} else {
+		doorbell_range = REG_SET_FIELD(doorbell_range,
+					       GDC0_BIF_VCN0_DOORBELL_RANGE, SIZE, 0);
+	}
+
+	WREG32_PCIE_PORT(reg, doorbell_range);
+}
+
 static void nbio_v7_7_enable_doorbell_aperture(struct amdgpu_device *adev,
 					       bool enable)
 {
@@ -238,6 +258,7 @@ const struct amdgpu_nbio_funcs nbio_v7_7_funcs = {
 	.mc_access_enable = nbio_v7_7_mc_access_enable,
 	.get_memsize = nbio_v7_7_get_memsize,
 	.sdma_doorbell_range = nbio_v7_7_sdma_doorbell_range,
+	.vcn_doorbell_range = nbio_v7_7_vcn_doorbell_range,
 	.enable_doorbell_aperture = nbio_v7_7_enable_doorbell_aperture,
 	.enable_doorbell_selfring_aperture = nbio_v7_7_enable_doorbell_selfring_aperture,
 	.ih_doorbell_range = nbio_v7_7_ih_doorbell_range,