drm/msm/dp: simplify stream clocks handling

There is only a single DP_STREAM_PM clock, stream_pixel. Instead of
using a separate dss_module_power instance for this single clock, handle
this clock directly. This allows us to drop several wrapping functions.
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Tested-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/576102/
Link: https://lore.kernel.org/r/20240126-dp-power-parser-cleanup-v3-6-098d5f581dd3@linaro.org

drivers/gpu/drm/msm/dp/dp_ctrl.c

@@ -79,6 +79,8 @@ struct dp_ctrl_private {
 	struct dp_parser *parser;
 	struct dp_catalog *catalog;
 
+	struct clk *pixel_clk;
+
 	struct completion idle_comp;
 	struct completion psr_op_comp;
 	struct completion video_comp;
@@ -1315,27 +1317,6 @@ static int dp_ctrl_setup_main_link(struct dp_ctrl_private *ctrl,
 	return ret;
 }
 
-static void dp_ctrl_set_clock_rate(struct dp_ctrl_private *ctrl,
-			enum dp_pm_type module, char *name, unsigned long rate)
-{
-	u32 num = ctrl->parser->mp[module].num_clk;
-	struct clk_bulk_data *cfg = ctrl->parser->mp[module].clocks;
-
-	while (num && strcmp(cfg->id, name)) {
-		num--;
-		cfg++;
-	}
-
-	drm_dbg_dp(ctrl->drm_dev, "setting rate=%lu on clk=%s\n",
-						rate, name);
-
-	if (num)
-		clk_set_rate(cfg->clk, rate);
-	else
-		DRM_ERROR("%s clock doesn't exit to set rate %lu\n",
-				name, rate);
-}
-
 int dp_ctrl_clk_enable(struct dp_ctrl *dp_ctrl,
 		       enum dp_pm_type pm_type, bool enable)
 {
@@ -1346,8 +1327,7 @@ int dp_ctrl_clk_enable(struct dp_ctrl *dp_ctrl,
 	ctrl = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
 
 	if (pm_type != DP_CORE_PM &&
-	    pm_type != DP_CTRL_PM &&
-	    pm_type != DP_STREAM_PM) {
+	    pm_type != DP_CTRL_PM) {
 		DRM_ERROR("unsupported ctrl module: %s\n",
 			  dp_parser_pm_name(pm_type));
 		return -EINVAL;
@@ -1366,12 +1346,6 @@ int dp_ctrl_clk_enable(struct dp_ctrl *dp_ctrl,
 			return 0;
 		}
 
-		if (pm_type == DP_STREAM_PM && ctrl->stream_clks_on) {
-			drm_dbg_dp(ctrl->drm_dev,
-				   "pixel clks already enabled\n");
-			return 0;
-		}
-
 		if ((pm_type == DP_CTRL_PM) && (!ctrl->core_clks_on)) {
 			drm_dbg_dp(ctrl->drm_dev,
 				   "Enable core clks before link clks\n");
@@ -1396,8 +1370,6 @@ int dp_ctrl_clk_enable(struct dp_ctrl *dp_ctrl,
 
 	if (pm_type == DP_CORE_PM)
 		ctrl->core_clks_on = enable;
-	else if (pm_type == DP_STREAM_PM)
-		ctrl->stream_clks_on = enable;
 	else
 		ctrl->link_clks_on = enable;
 
@@ -1729,13 +1701,22 @@ static int dp_ctrl_process_phy_test_request(struct dp_ctrl_private *ctrl)
 	}
 
 	pixel_rate = ctrl->panel->dp_mode.drm_mode.clock;
-	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel", pixel_rate * 1000);
+	ret = clk_set_rate(ctrl->pixel_clk, pixel_rate * 1000);
+	if (ret) {
+		DRM_ERROR("Failed to set pixel clock rate. ret=%d\n", ret);
+		return ret;
+	}
 
-	ret = dp_ctrl_clk_enable(&ctrl->dp_ctrl, DP_STREAM_PM, true);
+	if (ctrl->stream_clks_on) {
+		drm_dbg_dp(ctrl->drm_dev, "pixel clks already enabled\n");
+	} else {
+		ret = clk_prepare_enable(ctrl->pixel_clk);
 		if (ret) {
 			DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
 			return ret;
 		}
+		ctrl->stream_clks_on = true;
+	}
 
 	dp_ctrl_send_phy_test_pattern(ctrl);
 
@@ -1972,13 +1953,22 @@ int dp_ctrl_on_stream(struct dp_ctrl *dp_ctrl, bool force_link_train)
 		}
 	}
 
-	dp_ctrl_set_clock_rate(ctrl, DP_STREAM_PM, "stream_pixel", pixel_rate * 1000);
+	ret = clk_set_rate(ctrl->pixel_clk, pixel_rate * 1000);
+	if (ret) {
+		DRM_ERROR("Failed to set pixel clock rate. ret=%d\n", ret);
+		goto end;
+	}
 
-	ret = dp_ctrl_clk_enable(&ctrl->dp_ctrl, DP_STREAM_PM, true);
+	if (ctrl->stream_clks_on) {
+		drm_dbg_dp(ctrl->drm_dev, "pixel clks already enabled\n");
+	} else {
+		ret = clk_prepare_enable(ctrl->pixel_clk);
 		if (ret) {
-		DRM_ERROR("Unable to start pixel clocks. ret=%d\n", ret);
+			DRM_ERROR("Failed to start pixel clocks. ret=%d\n", ret);
 			goto end;
 		}
+		ctrl->stream_clks_on = true;
+	}
 
 	if (force_link_train || !dp_ctrl_channel_eq_ok(ctrl))
 		dp_ctrl_link_retrain(ctrl);
@@ -2031,11 +2021,8 @@ int dp_ctrl_off_link_stream(struct dp_ctrl *dp_ctrl)
 	dp_catalog_ctrl_mainlink_ctrl(ctrl->catalog, false);
 
 	if (ctrl->stream_clks_on) {
-		ret = dp_ctrl_clk_enable(&ctrl->dp_ctrl, DP_STREAM_PM, false);
-		if (ret) {
-			DRM_ERROR("Failed to disable pclk. ret=%d\n", ret);
-			return ret;
-		}
+		clk_disable_unprepare(ctrl->pixel_clk);
+		ctrl->stream_clks_on = false;
 	}
 
 	dev_pm_opp_set_rate(ctrl->dev, 0);
@@ -2103,9 +2090,10 @@ int dp_ctrl_off(struct dp_ctrl *dp_ctrl)
 
 	dp_catalog_ctrl_reset(ctrl->catalog);
 
-	ret = dp_ctrl_clk_enable(&ctrl->dp_ctrl, DP_STREAM_PM, false);
-	if (ret)
-		DRM_ERROR("Failed to disable pixel clocks. ret=%d\n", ret);
+	if (ctrl->stream_clks_on) {
+		clk_disable_unprepare(ctrl->pixel_clk);
+		ctrl->stream_clks_on = false;
+	}
 
 	dev_pm_opp_set_rate(ctrl->dev, 0);
 	ret = dp_ctrl_clk_enable(&ctrl->dp_ctrl, DP_CTRL_PM, false);
@@ -2169,7 +2157,7 @@ static int dp_ctrl_clk_init(struct dp_ctrl *dp_ctrl)
 {
 	struct dp_ctrl_private *ctrl_private;
 	int rc = 0;
-	struct dss_module_power *core, *ctrl, *stream;
+	struct dss_module_power *core, *ctrl;
 	struct device *dev;
 
 	ctrl_private = container_of(dp_ctrl, struct dp_ctrl_private, dp_ctrl);
@@ -2177,7 +2165,6 @@ static int dp_ctrl_clk_init(struct dp_ctrl *dp_ctrl)
 
 	core = &ctrl_private->parser->mp[DP_CORE_PM];
 	ctrl = &ctrl_private->parser->mp[DP_CTRL_PM];
-	stream = &ctrl_private->parser->mp[DP_STREAM_PM];
 
 	rc = devm_clk_bulk_get(dev, core->num_clk, core->clocks);
 	if (rc)
@@ -2187,9 +2174,9 @@ static int dp_ctrl_clk_init(struct dp_ctrl *dp_ctrl)
 	if (rc)
 		return -ENODEV;
 
-	rc = devm_clk_bulk_get(dev, stream->num_clk, stream->clocks);
-	if (rc)
-		return -ENODEV;
+	ctrl_private->pixel_clk = devm_clk_get(dev, "stream_pixel");
+	if (IS_ERR(ctrl_private->pixel_clk))
+		return PTR_ERR(ctrl_private->pixel_clk);
 
 	return 0;
 }

drivers/gpu/drm/msm/dp/dp_parser.c

@@ -150,12 +150,11 @@ static inline bool dp_parser_check_prefix(const char *clk_prefix,
 static int dp_parser_init_clk_data(struct dp_parser *parser)
 {
 	int num_clk, i, rc;
-	int core_clk_count = 0, ctrl_clk_count = 0, stream_clk_count = 0;
+	int core_clk_count = 0, ctrl_clk_count = 0;
 	const char *clk_name;
 	struct device *dev = &parser->pdev->dev;
 	struct dss_module_power *core_power = &parser->mp[DP_CORE_PM];
 	struct dss_module_power *ctrl_power = &parser->mp[DP_CTRL_PM];
-	struct dss_module_power *stream_power = &parser->mp[DP_STREAM_PM];
 
 	num_clk = of_property_count_strings(dev->of_node, "clock-names");
 	if (num_clk <= 0) {
@@ -174,9 +173,6 @@ static int dp_parser_init_clk_data(struct dp_parser *parser)
 
 		if (dp_parser_check_prefix("ctrl", clk_name))
 			ctrl_clk_count++;
-
-		if (dp_parser_check_prefix("stream", clk_name))
-			stream_clk_count++;
 	}
 
 	/* Initialize the CORE power module */
@@ -207,47 +203,30 @@ static int dp_parser_init_clk_data(struct dp_parser *parser)
 		return -ENOMEM;
 	}
 
-	/* Initialize the STREAM power module */
-	if (stream_clk_count == 0) {
-		DRM_ERROR("no stream (pixel) clocks are defined\n");
-		return -EINVAL;
-	}
-
-	stream_power->num_clk = stream_clk_count;
-	stream_power->clocks = devm_kcalloc(dev,
-			stream_power->num_clk, sizeof(struct clk_bulk_data),
-			GFP_KERNEL);
-	if (!stream_power->clocks) {
-		stream_power->num_clk = 0;
-		return -ENOMEM;
-	}
-
-	return 0;
+	return num_clk;
 }
 
 static int dp_parser_clock(struct dp_parser *parser)
 {
 	int rc = 0, i = 0;
 	int num_clk = 0;
-	int core_clk_index = 0, ctrl_clk_index = 0, stream_clk_index = 0;
-	int core_clk_count = 0, ctrl_clk_count = 0, stream_clk_count = 0;
+	int core_clk_index = 0, ctrl_clk_index = 0;
+	int core_clk_count = 0, ctrl_clk_count = 0;
 	const char *clk_name;
 	struct device *dev = &parser->pdev->dev;
 	struct dss_module_power *core_power = &parser->mp[DP_CORE_PM];
 	struct dss_module_power *ctrl_power = &parser->mp[DP_CTRL_PM];
-	struct dss_module_power *stream_power = &parser->mp[DP_STREAM_PM];
 
 	rc =  dp_parser_init_clk_data(parser);
-	if (rc) {
+	if (rc < 0) {
 		DRM_ERROR("failed to initialize power data %d\n", rc);
-		return -EINVAL;
+		return rc;
 	}
 
+	num_clk = rc;
+
 	core_clk_count = core_power->num_clk;
 	ctrl_clk_count = ctrl_power->num_clk;
-	stream_clk_count = stream_power->num_clk;
-
-	num_clk = core_clk_count + ctrl_clk_count + stream_clk_count;
 
 	for (i = 0; i < num_clk; i++) {
 		rc = of_property_read_string_index(dev->of_node, "clock-names",
@@ -260,10 +239,6 @@ static int dp_parser_clock(struct dp_parser *parser)
 				core_clk_index < core_clk_count) {
 			core_power->clocks[core_clk_index].id = devm_kstrdup(dev, clk_name, GFP_KERNEL);
 			core_clk_index++;
-		} else if (dp_parser_check_prefix("stream", clk_name) &&
-				stream_clk_index < stream_clk_count) {
-			stream_power->clocks[stream_clk_index].id = devm_kstrdup(dev, clk_name, GFP_KERNEL);
-			stream_clk_index++;
 		} else if (dp_parser_check_prefix("ctrl", clk_name) &&
 			   ctrl_clk_index < ctrl_clk_count) {
 			ctrl_power->clocks[ctrl_clk_index].id = devm_kstrdup(dev, clk_name, GFP_KERNEL);

drivers/gpu/drm/msm/dp/dp_parser.h

@@ -19,7 +19,6 @@
 enum dp_pm_type {
 	DP_CORE_PM,
 	DP_CTRL_PM,
-	DP_STREAM_PM,
 	DP_MAX_PM
 };
 
@@ -40,7 +39,6 @@ static inline const char *dp_parser_pm_name(enum dp_pm_type module)
 	switch (module) {
 	case DP_CORE_PM:	return "DP_CORE_PM";
 	case DP_CTRL_PM:	return "DP_CTRL_PM";
-	case DP_STREAM_PM:	return "DP_STREAM_PM";
 	default:		return "???";
 	}
 }