drm/msm/dpu: add writeback support for sc7280

Add writeback support for sc7280. This was validated with kms_writeback
test case in IGT.
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/535244/
Link: https://lore.kernel.org/r/20230503223905.24754-1-quic_abhinavk@quicinc.comSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_7_2_sc7280.h

@@ -31,6 +31,7 @@ static const struct dpu_mdp_cfg sc7280_mdp[] = {
 	.clk_ctrls[DPU_CLK_CTRL_DMA0] = { .reg_off = 0x2ac, .bit_off = 8 },
 	.clk_ctrls[DPU_CLK_CTRL_DMA1] = { .reg_off = 0x2b4, .bit_off = 8 },
 	.clk_ctrls[DPU_CLK_CTRL_DMA2] = { .reg_off = 0x2c4, .bit_off = 8 },
+	.clk_ctrls[DPU_CLK_CTRL_WB2] = { .reg_off = 0x3b8, .bit_off = 24 },
 	},
 };
 
@@ -93,6 +94,11 @@ static const struct dpu_pingpong_cfg sc7280_pp[] = {
 	PP_BLK_DITHER("pingpong_3", PINGPONG_3, 0x6c000, 0, sc7280_pp_sblk, -1, -1),
 };
 
+static const struct dpu_wb_cfg sc7280_wb[] = {
+	WB_BLK("wb_2", WB_2, 0x65000, WB_SM8250_MASK, DPU_CLK_CTRL_WB2, 6,
+			VBIF_RT, MDP_SSPP_TOP0_INTR, 4096, 4),
+};
+
 static const struct dpu_intf_cfg sc7280_intf[] = {
 	INTF_BLK("intf_0", INTF_0, 0x34000, 0x280, INTF_DP, MSM_DP_CONTROLLER_0, 24, INTF_SC7280_MASK, MDP_SSPP_TOP0_INTR, 24, 25),
 	INTF_BLK("intf_1", INTF_1, 0x35000, 0x2c4, INTF_DSI, 0, 24, INTF_SC7280_MASK, MDP_SSPP_TOP0_INTR, 26, 27),
@@ -142,6 +148,8 @@ const struct dpu_mdss_cfg dpu_sc7280_cfg = {
 	.mixer = sc7280_lm,
 	.pingpong_count = ARRAY_SIZE(sc7280_pp),
 	.pingpong = sc7280_pp,
+	.wb_count = ARRAY_SIZE(sc7280_wb),
+	.wb = sc7280_wb,
 	.intf_count = ARRAY_SIZE(sc7280_intf),
 	.intf = sc7280_intf,
 	.vbif_count = ARRAY_SIZE(sdm845_vbif),