drm/msm/dsi: use DRM DSC helpers for DSC setup

Use new DRM DSC helpers to setup DSI DSC configuration. The
initial_scale_value needs to be adjusted according to the standard, but
this is a separate change.

Signed-off-by: Dmitry Baryshkov <[e-mail]>
Reviewed-by: Abhinav Kumar <[e-mail]>
Reviewed-by: Marijn Suijten <[e-mail]>
Signed-off-by: Jessica Zhang <[e-mail]>
Patchwork: https://patchwork.freedesktop.org/patch/539276/
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Dmitry Baryshkov <[e-mail]>

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

···
 	return -EINVAL;
 }
 
-static u32 dsi_dsc_rc_buf_thresh[DSC_NUM_BUF_RANGES - 1] = {
-	0x0e, 0x1c, 0x2a, 0x38, 0x46, 0x54, 0x62,
-	0x69, 0x70, 0x77, 0x79, 0x7b, 0x7d, 0x7e
-};
-
-/* only 8bpc, 8bpp added */
-static char min_qp[DSC_NUM_BUF_RANGES] = {
-	0, 0, 1, 1, 3, 3, 3, 3, 3, 3, 5, 5, 5, 7, 13
-};
-
-static char max_qp[DSC_NUM_BUF_RANGES] = {
-	4, 4, 5, 6, 7, 7, 7, 8, 9, 10, 11, 12, 13, 13, 15
-};
-
-static char bpg_offset[DSC_NUM_BUF_RANGES] = {
-	2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
-};
-
 static int dsi_populate_dsc_params(struct msm_dsi_host *msm_host, struct drm_dsc_config *dsc)
 {
-	int i;
-	u16 bpp = dsc->bits_per_pixel >> 4;
+	int ret;
 
 	if (dsc->bits_per_pixel & 0xf) {
 		DRM_DEV_ERROR(&msm_host->pdev->dev, "DSI does not support fractional bits_per_pixel\n");
···
 		return -EOPNOTSUPP;
 	}
 
-	dsc->rc_model_size = 8192;
-	dsc->first_line_bpg_offset = 12;
-	dsc->rc_edge_factor = 6;
-	dsc->rc_tgt_offset_high = 3;
-	dsc->rc_tgt_offset_low = 3;
 	dsc->simple_422 = 0;
 	dsc->convert_rgb = 1;
 	dsc->vbr_enable = 0;
 
-	/* handle only bpp = bpc = 8 */
-	for (i = 0; i < DSC_NUM_BUF_RANGES - 1 ; i++)
-		dsc->rc_buf_thresh[i] = dsi_dsc_rc_buf_thresh[i];
+	drm_dsc_set_const_params(dsc);
+	drm_dsc_set_rc_buf_thresh(dsc);
 
-	for (i = 0; i < DSC_NUM_BUF_RANGES; i++) {
-		dsc->rc_range_params[i].range_min_qp = min_qp[i];
-		dsc->rc_range_params[i].range_max_qp = max_qp[i];
-		/*
-		 * Range BPG Offset contains two's-complement signed values that fill
-		 * 8 bits, yet the registers and DCS PPS field are only 6 bits wide.
-		 */
-		dsc->rc_range_params[i].range_bpg_offset = bpg_offset[i] & DSC_RANGE_BPG_OFFSET_MASK;
+	/* handle only bpp = bpc = 8, pre-SCR panels */
+	ret = drm_dsc_setup_rc_params(dsc, DRM_DSC_1_1_PRE_SCR);
+	if (ret) {
+		DRM_DEV_ERROR(&msm_host->pdev->dev, "could not find DSC RC parameters\n");
+		return ret;
 	}
 
-	dsc->initial_offset = 6144;		/* Not bpp 12 */
-	if (bpp != 8)
-		dsc->initial_offset = 2048;	/* bpp = 12 */
-
-	if (dsc->bits_per_component <= 10)
-		dsc->mux_word_size = DSC_MUX_WORD_SIZE_8_10_BPC;
-	else
-		dsc->mux_word_size = DSC_MUX_WORD_SIZE_12_BPC;
-
-	dsc->initial_xmit_delay = 512;
 	dsc->initial_scale_value = 32;
-	dsc->first_line_bpg_offset = 12;
 	dsc->line_buf_depth = dsc->bits_per_component + 1;
-
-	/* bpc 8 */
-	dsc->flatness_min_qp = 3;
-	dsc->flatness_max_qp = 12;
-	dsc->rc_quant_incr_limit0 = 11;
-	dsc->rc_quant_incr_limit1 = 11;
 
 	return drm_dsc_compute_rc_parameters(dsc);
 }