[PATCH v5 4/6] drm/msm: dsi: Use OPP API to set clk/perf state

[Rajendra Nayak]

On SDM845 DSI needs to express a perforamnce state
requirement on a power domain depending on the clock rates.
Use OPP table from DT to register with OPP framework and use
dev_pm_opp_set_rate() to set the clk/perf state.

Signed-off-by: Rajendra Nayak <rnayak at codeaurora.org>
Cc: Rob Clark <robdclark at gmail.com>
Cc: Sean Paul <sean at poorly.run>
Cc: dri-devel at lists.freedesktop.org
---
 drivers/gpu/drm/msm/dsi/dsi.h      |  2 ++
 drivers/gpu/drm/msm/dsi/dsi_cfg.c  |  4 +--
 drivers/gpu/drm/msm/dsi/dsi_host.c | 58 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
index 4de771d..ba7583c 100644
--- a/drivers/gpu/drm/msm/dsi/dsi.h
+++ b/drivers/gpu/drm/msm/dsi/dsi.h
@@ -180,10 +180,12 @@ int msm_dsi_runtime_suspend(struct device *dev);
 int msm_dsi_runtime_resume(struct device *dev);
 int dsi_link_clk_set_rate_6g(struct msm_dsi_host *msm_host);
 int dsi_link_clk_set_rate_v2(struct msm_dsi_host *msm_host);
+int dsi_link_clk_set_rate_6g_v2(struct msm_dsi_host *msm_host);
 int dsi_link_clk_enable_6g(struct msm_dsi_host *msm_host);
 int dsi_link_clk_enable_v2(struct msm_dsi_host *msm_host);
 void dsi_link_clk_disable_6g(struct msm_dsi_host *msm_host);
 void dsi_link_clk_disable_v2(struct msm_dsi_host *msm_host);
+void dsi_link_clk_disable_6g_v2(struct msm_dsi_host *msm_host);
 int dsi_tx_buf_alloc_6g(struct msm_dsi_host *msm_host, int size);
 int dsi_tx_buf_alloc_v2(struct msm_dsi_host *msm_host, int size);
 void *dsi_tx_buf_get_6g(struct msm_dsi_host *msm_host);
diff --git a/drivers/gpu/drm/msm/dsi/dsi_cfg.c b/drivers/gpu/drm/msm/dsi/dsi_cfg.c
index 813d69d..773c4fe 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_cfg.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_cfg.c
@@ -210,9 +210,9 @@ static const struct msm_dsi_host_cfg_ops msm_dsi_6g_host_ops = {
 };
 
 static const struct msm_dsi_host_cfg_ops msm_dsi_6g_v2_host_ops = {
-	.link_clk_set_rate = dsi_link_clk_set_rate_6g,
+	.link_clk_set_rate = dsi_link_clk_set_rate_6g_v2,
 	.link_clk_enable = dsi_link_clk_enable_6g,
-	.link_clk_disable = dsi_link_clk_disable_6g,
+	.link_clk_disable = dsi_link_clk_disable_6g_v2,
 	.clk_init_ver = dsi_clk_init_6g_v2,
 	.tx_buf_alloc = dsi_tx_buf_alloc_6g,
 	.tx_buf_get = dsi_tx_buf_get_6g,
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 11ae5b8..890531c 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -14,6 +14,7 @@
 #include <linux/of_graph.h>
 #include <linux/of_irq.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/pm_opp.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/spinlock.h>
@@ -111,6 +112,9 @@ struct msm_dsi_host {
 	struct clk *pixel_clk_src;
 	struct clk *byte_intf_clk;
 
+	struct opp_table *opp_table;
+	bool has_opp_table;
+
 	u32 byte_clk_rate;
 	u32 pixel_clk_rate;
 	u32 esc_clk_rate;
@@ -537,6 +541,38 @@ int dsi_link_clk_set_rate_6g(struct msm_dsi_host *msm_host)
 	return 0;
 }
 
+int dsi_link_clk_set_rate_6g_v2(struct msm_dsi_host *msm_host)
+{
+	int ret;
+	struct device *dev = &msm_host->pdev->dev;
+
+	DBG("Set clk rates: pclk=%d, byteclk=%d",
+		msm_host->mode->clock, msm_host->byte_clk_rate);
+
+	ret = dev_pm_opp_set_rate(dev, msm_host->byte_clk_rate);
+	if (ret) {
+		pr_err("%s: dev_pm_opp_set_rate failed %d\n", __func__, ret);
+		return ret;
+	}
+
+	ret = clk_set_rate(msm_host->pixel_clk, msm_host->pixel_clk_rate);
+	if (ret) {
+		pr_err("%s: Failed to set rate pixel clk, %d\n", __func__, ret);
+		return ret;
+	}
+
+	if (msm_host->byte_intf_clk) {
+		ret = clk_set_rate(msm_host->byte_intf_clk,
+				   msm_host->byte_clk_rate / 2);
+		if (ret) {
+			pr_err("%s: Failed to set rate byte intf clk, %d\n",
+			       __func__, ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
 
 int dsi_link_clk_enable_6g(struct msm_dsi_host *msm_host)
 {
@@ -665,6 +701,13 @@ void dsi_link_clk_disable_6g(struct msm_dsi_host *msm_host)
 	clk_disable_unprepare(msm_host->byte_clk);
 }
 
+void dsi_link_clk_disable_6g_v2(struct msm_dsi_host *msm_host)
+{
+	/* Drop the performance state vote */
+	dev_pm_opp_set_rate(&msm_host->pdev->dev, 0);
+	dsi_link_clk_disable_6g(msm_host);
+}
+
 void dsi_link_clk_disable_v2(struct msm_dsi_host *msm_host)
 {
 	clk_disable_unprepare(msm_host->pixel_clk);
@@ -1879,6 +1922,18 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
 		goto fail;
 	}
 
+	msm_host->opp_table = dev_pm_opp_set_clkname(&pdev->dev, "byte");
+	if (IS_ERR(msm_host->opp_table))
+		return PTR_ERR(msm_host->opp_table);
+	/* OPP table is optional */
+	ret = dev_pm_opp_of_add_table(&pdev->dev);
+	if (!ret) {
+		msm_host->has_opp_table = true;
+	} else if (ret != -ENODEV) {
+		dev_err(&pdev->dev, "invalid OPP table in device tree\n");
+		return ret;
+	}
+
 	init_completion(&msm_host->dma_comp);
 	init_completion(&msm_host->video_comp);
 	mutex_init(&msm_host->dev_mutex);
@@ -1914,6 +1969,9 @@ void msm_dsi_host_destroy(struct mipi_dsi_host *host)
 	mutex_destroy(&msm_host->cmd_mutex);
 	mutex_destroy(&msm_host->dev_mutex);
 
+	if (msm_host->has_opp_table)
+		dev_pm_opp_of_remove_table(&msm_host->pdev->dev);
+	dev_pm_opp_put_clkname(msm_host->opp_table);
 	pm_runtime_disable(&msm_host->pdev->dev);
 }
 
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