drm/msm/dsi: set VIDEO_COMPRESSION_MODE_CTRL_WC

Video mode DSC won't work if this field is not set correctly. Set it to fix
video mode DSC (for slice_per_pkt==1 cases at least).

Fixes: 08802f51 ("drm/msm/dsi: Add support for DSC configuration")
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Jun Nie <jun.nie@linaro.org>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8550-QRD
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8650-QRD
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8650-HDK
Reviewed-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/596234/
Link: https://lore.kernel.org/r/20240530-msm-drm-dsc-dsi-video-upstream-4-v6-5-2ab1d334c657@linaro.orgSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

drivers/gpu/drm/msm/dsi/dsi_host.c

@@ -857,6 +857,7 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
 	u32 slice_per_intf, total_bytes_per_intf;
 	u32 pkt_per_line;
 	u32 eol_byte_num;
+	u32 bytes_per_pkt;
 
 	/* first calculate dsc parameters and then program
 	 * compress mode registers
@@ -864,6 +865,7 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
 	slice_per_intf = msm_dsc_get_slices_per_intf(dsc, hdisplay);
 
 	total_bytes_per_intf = dsc->slice_chunk_size * slice_per_intf;
+	bytes_per_pkt = dsc->slice_chunk_size; /* * slice_per_pkt; */
 
 	eol_byte_num = total_bytes_per_intf % 3;
 
@@ -901,6 +903,7 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
 		dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL, reg_ctrl);
 		dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL2, reg_ctrl2);
 	} else {
+		reg |= DSI_VIDEO_COMPRESSION_MODE_CTRL_WC(bytes_per_pkt);
 		dsi_write(msm_host, REG_DSI_VIDEO_COMPRESSION_MODE_CTRL, reg);
 	}
 }