drm/msm/dsi: Add support for DSC configuration

When DSC is enabled, we need to configure DSI registers accordingly and
configure the respective stream compression registers.

Add support to calculate the register setting based on DSC params and
timing information and configure these registers.
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Patchwork: https://patchwork.freedesktop.org/patch/480934/
Link: https://lore.kernel.org/r/20220406094031.1027376-15-vkoul@kernel.orgSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

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

@@ -912,6 +912,65 @@ static void dsi_ctrl_config(struct msm_dsi_host *msm_host, bool enable,
 		dsi_write(msm_host, REG_DSI_CPHY_MODE_CTRL, BIT(0));
 }
 
+static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mode, u32 hdisplay)
+{
+	struct msm_display_dsc_config *dsc = msm_host->dsc;
+	u32 reg, intf_width, reg_ctrl, reg_ctrl2;
+	u32 slice_per_intf, total_bytes_per_intf;
+	u32 pkt_per_line;
+	u32 bytes_in_slice;
+	u32 eol_byte_num;
+
+	/* first calculate dsc parameters and then program
+	 * compress mode registers
+	 */
+	intf_width = hdisplay;
+	slice_per_intf = DIV_ROUND_UP(intf_width, dsc->drm->slice_width);
+
+	/* If slice_per_pkt is greater than slice_per_intf
+	 * then default to 1. This can happen during partial
+	 * update.
+	 */
+	if (slice_per_intf > dsc->drm->slice_count)
+		dsc->drm->slice_count = 1;
+
+	slice_per_intf = DIV_ROUND_UP(hdisplay, dsc->drm->slice_width);
+	bytes_in_slice = DIV_ROUND_UP(dsc->drm->slice_width * dsc->drm->bits_per_pixel, 8);
+
+	dsc->drm->slice_chunk_size = bytes_in_slice;
+
+	total_bytes_per_intf = bytes_in_slice * slice_per_intf;
+
+	eol_byte_num = total_bytes_per_intf % 3;
+	pkt_per_line = slice_per_intf / dsc->drm->slice_count;
+
+	if (is_cmd_mode) /* packet data type */
+		reg = DSI_COMMAND_COMPRESSION_MODE_CTRL_STREAM0_DATATYPE(MIPI_DSI_DCS_LONG_WRITE);
+	else
+		reg = DSI_VIDEO_COMPRESSION_MODE_CTRL_DATATYPE(MIPI_DSI_COMPRESSED_PIXEL_STREAM);
+
+	/* DSI_VIDEO_COMPRESSION_MODE & DSI_COMMAND_COMPRESSION_MODE
+	 * registers have similar offsets, so for below common code use
+	 * DSI_VIDEO_COMPRESSION_MODE_XXXX for setting bits
+	 */
+	reg |= DSI_VIDEO_COMPRESSION_MODE_CTRL_PKT_PER_LINE(pkt_per_line >> 1);
+	reg |= DSI_VIDEO_COMPRESSION_MODE_CTRL_EOL_BYTE_NUM(eol_byte_num);
+	reg |= DSI_VIDEO_COMPRESSION_MODE_CTRL_EN;
+
+	if (is_cmd_mode) {
+		reg_ctrl = dsi_read(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL);
+		reg_ctrl2 = dsi_read(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL2);
+
+		reg_ctrl |= reg;
+		reg_ctrl2 |= DSI_COMMAND_COMPRESSION_MODE_CTRL2_STREAM0_SLICE_WIDTH(bytes_in_slice);
+
+		dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL, reg);
+		dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL2, reg_ctrl2);
+	} else {
+		dsi_write(msm_host, REG_DSI_VIDEO_COMPRESSION_MODE_CTRL, reg);
+	}
+}
+
 static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
 {
 	struct drm_display_mode *mode = msm_host->mode;
@@ -944,7 +1003,38 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
 		hdisplay /= 2;
 	}
 
+	if (msm_host->dsc) {
+		struct msm_display_dsc_config *dsc = msm_host->dsc;
+
+		/* update dsc params with timing params */
+		if (!dsc || !mode->hdisplay || !mode->vdisplay) {
+			pr_err("DSI: invalid input: pic_width: %d pic_height: %d\n",
+			       mode->hdisplay, mode->vdisplay);
+			return;
+		}
+
+		dsc->drm->pic_width = mode->hdisplay;
+		dsc->drm->pic_height = mode->vdisplay;
+		DBG("Mode %dx%d\n", dsc->drm->pic_width, dsc->drm->pic_height);
+
+		/* we do the calculations for dsc parameters here so that
+		 * panel can use these parameters
+		 */
+		dsi_populate_dsc_params(dsc);
+
+		/* Divide the display by 3 but keep back/font porch and
+		 * pulse width same
+		 */
+		h_total -= hdisplay;
+		hdisplay /= 3;
+		h_total += hdisplay;
+		ha_end = ha_start + hdisplay;
+	}
+
 	if (msm_host->mode_flags & MIPI_DSI_MODE_VIDEO) {
+		if (msm_host->dsc)
+			dsi_update_dsc_timing(msm_host, false, mode->hdisplay);
+
 		dsi_write(msm_host, REG_DSI_ACTIVE_H,
 			DSI_ACTIVE_H_START(ha_start) |
 			DSI_ACTIVE_H_END(ha_end));
@@ -963,8 +1053,14 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
 			DSI_ACTIVE_VSYNC_VPOS_START(vs_start) |
 			DSI_ACTIVE_VSYNC_VPOS_END(vs_end));
 	} else {		/* command mode */
+		if (msm_host->dsc)
+			dsi_update_dsc_timing(msm_host, true, mode->hdisplay);
+
 		/* image data and 1 byte write_memory_start cmd */
+		if (!msm_host->dsc)
 			wc = hdisplay * dsi_get_bpp(msm_host->format) / 8 + 1;
+		else
+			wc = mode->hdisplay / 2 + 1;
 
 		dsi_write(msm_host, REG_DSI_CMD_MDP_STREAM0_CTRL,
 			DSI_CMD_MDP_STREAM0_CTRL_WORD_COUNT(wc) |