diff mbox series

[v7,45/47] PM / devfreq: tegra30: Support interconnect and OPPs from device-tree

Message ID 20201104164923.21238-46-digetx@gmail.com (mailing list archive)
State Not Applicable, archived
Delegated to: Chanwoo Choi
Headers show
Series Introduce memory interconnect for NVIDIA Tegra SoCs | expand

Commit Message

Dmitry Osipenko Nov. 4, 2020, 4:49 p.m. UTC 
This patch moves ACTMON driver away from generating OPP table by itself,
transitioning it to use the table which comes from device-tree. This
change breaks compatibility with older device-trees in order to bring
support for the interconnect framework to the driver. This is a mandatory
change which needs to be done in order to implement interconnect-based
memory DVFS. Users of legacy device-trees will get a message telling that
theirs DT needs to be upgraded. Now ACTMON issues memory bandwidth request
using dev_pm_opp_set_bw(), instead of driving EMC clock rate directly.

Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Nicolas Chauvet <kwizart@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/devfreq/tegra30-devfreq.c | 96 +++++++++++++++++--------------
 1 file changed, 54 insertions(+), 42 deletions(-)

Comments

Chanwoo Choi Nov. 5, 2020, 2:22 a.m. UTC | #1 
Hi Dmitry,

On 11/5/20 1:49 AM, Dmitry Osipenko wrote:
> This patch moves ACTMON driver away from generating OPP table by itself,
> transitioning it to use the table which comes from device-tree. This
> change breaks compatibility with older device-trees in order to bring
> support for the interconnect framework to the driver. This is a mandatory
> change which needs to be done in order to implement interconnect-based
> memory DVFS. Users of legacy device-trees will get a message telling that
> theirs DT needs to be upgraded. Now ACTMON issues memory bandwidth request
> using dev_pm_opp_set_bw(), instead of driving EMC clock rate directly.
> 
> Tested-by: Peter Geis <pgwipeout@gmail.com>
> Tested-by: Nicolas Chauvet <kwizart@gmail.com>
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
>  drivers/devfreq/tegra30-devfreq.c | 96 +++++++++++++++++--------------
>  1 file changed, 54 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c
> index 38cc0d014738..4db027ca17e1 100644
> --- a/drivers/devfreq/tegra30-devfreq.c
> +++ b/drivers/devfreq/tegra30-devfreq.c
> @@ -19,6 +19,8 @@
>  #include <linux/reset.h>
>  #include <linux/workqueue.h>
>  
> +#include <soc/tegra/fuse.h>
> +
>  #include "governor.h"
>  
>  #define ACTMON_GLB_STATUS					0x0
> @@ -155,6 +157,7 @@ struct tegra_devfreq_device {
>  
>  struct tegra_devfreq {
>  	struct devfreq		*devfreq;
> +	struct opp_table	*opp_table;
>  
>  	struct reset_control	*reset;
>  	struct clk		*clock;
> @@ -612,34 +615,19 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra)
>  static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
>  				u32 flags)
>  {
> -	struct tegra_devfreq *tegra = dev_get_drvdata(dev);
> -	struct devfreq *devfreq = tegra->devfreq;
>  	struct dev_pm_opp *opp;
> -	unsigned long rate;
> -	int err;
> +	int ret;
>  
>  	opp = devfreq_recommended_opp(dev, freq, flags);
>  	if (IS_ERR(opp)) {
>  		dev_err(dev, "Failed to find opp for %lu Hz\n", *freq);
>  		return PTR_ERR(opp);
>  	}
> -	rate = dev_pm_opp_get_freq(opp);
> -	dev_pm_opp_put(opp);
> -
> -	err = clk_set_min_rate(tegra->emc_clock, rate * KHZ);
> -	if (err)
> -		return err;
> -
> -	err = clk_set_rate(tegra->emc_clock, 0);
> -	if (err)
> -		goto restore_min_rate;
> -
> -	return 0;
>  
> -restore_min_rate:
> -	clk_set_min_rate(tegra->emc_clock, devfreq->previous_freq);
> +	ret = dev_pm_opp_set_bw(dev, opp);
> +	dev_pm_opp_put(opp);
>  
> -	return err;
> +	return ret;
>  }
>  
>  static int tegra_devfreq_get_dev_status(struct device *dev,
> @@ -655,7 +643,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev,
>  	stat->private_data = tegra;
>  
>  	/* The below are to be used by the other governors */
> -	stat->current_frequency = cur_freq;
> +	stat->current_frequency = cur_freq * KHZ;
>  
>  	actmon_dev = &tegra->devices[MCALL];
>  
> @@ -705,7 +693,12 @@ static int tegra_governor_get_target(struct devfreq *devfreq,
>  		target_freq = max(target_freq, dev->target_freq);
>  	}
>  
> -	*freq = target_freq;
> +	/*
> +	 * tegra-devfreq driver operates with KHz units, while OPP table
> +	 * entries use Hz units. Hence we need to convert the units for the
> +	 * devfreq core.
> +	 */
> +	*freq = target_freq * KHZ;
>  
>  	return 0;
>  }
> @@ -774,13 +767,22 @@ static struct devfreq_governor tegra_devfreq_governor = {
>  
>  static int tegra_devfreq_probe(struct platform_device *pdev)
>  {
> +	u32 hw_version = BIT(tegra_sku_info.soc_speedo_id);
>  	struct tegra_devfreq_device *dev;
>  	struct tegra_devfreq *tegra;
> +	struct opp_table *opp_table;
>  	struct devfreq *devfreq;
>  	unsigned int i;
>  	long rate;
>  	int err;
>  
> +	/* legacy device-trees don't have OPP table and must be updated */
> +	if (!device_property_present(&pdev->dev, "operating-points-v2")) {
> +		dev_err(&pdev->dev,
> +			"OPP table not found, please update your device tree\n");
> +		return -ENODEV;
> +	}
> +
>  	tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
>  	if (!tegra)
>  		return -ENOMEM;
> @@ -822,11 +824,31 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
>  		return err;
>  	}
>  
> +	tegra->opp_table = dev_pm_opp_get_opp_table(&pdev->dev);
> +	err = PTR_ERR_OR_ZERO(tegra->opp_table);
> +	if (err) {
> +		dev_err(&pdev->dev, "Failed to prepare OPP table: %d\n", err);
> +		return err;
> +	}
> +
> +	opp_table = dev_pm_opp_set_supported_hw(&pdev->dev, &hw_version, 1);
> +	err = PTR_ERR_OR_ZERO(opp_table);
> +	if (err) {
> +		dev_err(&pdev->dev, "Failed to set supported HW: %d\n", err);
> +		goto put_table;
> +	}
> +
> +	err = dev_pm_opp_of_add_table(&pdev->dev);
> +	if (err) {
> +		dev_err(&pdev->dev, "Failed to add OPP table: %d\n", err);
> +		goto put_hw;
> +	}
> +
>  	err = clk_prepare_enable(tegra->clock);
>  	if (err) {
>  		dev_err(&pdev->dev,
>  			"Failed to prepare and enable ACTMON clock\n");
> -		return err;
> +		goto remove_table;
>  	}
>  
>  	err = reset_control_reset(tegra->reset);
> @@ -850,23 +872,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
>  		dev->regs = tegra->regs + dev->config->offset;
>  	}
>  
> -	for (rate = 0; rate <= tegra->max_freq * KHZ; rate++) {
> -		rate = clk_round_rate(tegra->emc_clock, rate);
> -
> -		if (rate < 0) {
> -			dev_err(&pdev->dev,
> -				"Failed to round clock rate: %ld\n", rate);
> -			err = rate;
> -			goto remove_opps;
> -		}
> -
> -		err = dev_pm_opp_add(&pdev->dev, rate / KHZ, 0);
> -		if (err) {
> -			dev_err(&pdev->dev, "Failed to add OPP: %d\n", err);
> -			goto remove_opps;
> -		}
> -	}
> -
>  	platform_set_drvdata(pdev, tegra);
>  
>  	tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb;
> @@ -882,7 +887,6 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
>  	}
>  
>  	tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock);
> -	tegra_devfreq_profile.initial_freq /= KHZ;
>  
>  	devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile,
>  				     "tegra_actmon", NULL);
> @@ -902,6 +906,12 @@ static int tegra_devfreq_probe(struct platform_device *pdev)
>  	reset_control_reset(tegra->reset);
>  disable_clk:
>  	clk_disable_unprepare(tegra->clock);
> +remove_table:
> +	dev_pm_opp_of_remove_table(&pdev->dev);
> +put_hw:
> +	dev_pm_opp_put_supported_hw(tegra->opp_table);
> +put_table:
> +	dev_pm_opp_put_opp_table(tegra->opp_table);
>  
>  	return err;
>  }
> @@ -913,11 +923,13 @@ static int tegra_devfreq_remove(struct platform_device *pdev)
>  	devfreq_remove_device(tegra->devfreq);
>  	devfreq_remove_governor(&tegra_devfreq_governor);
>  
> -	dev_pm_opp_remove_all_dynamic(&pdev->dev);
> -
>  	reset_control_reset(tegra->reset);
>  	clk_disable_unprepare(tegra->clock);
>  
> +	dev_pm_opp_of_remove_table(&pdev->dev);
> +	dev_pm_opp_put_supported_hw(tegra->opp_table);
> +	dev_pm_opp_put_opp_table(tegra->opp_table);
> +
>  	return 0;
>  }
>  
> 

Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
diff mbox series

Patch

diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c
index 38cc0d014738..4db027ca17e1 100644
--- a/drivers/devfreq/tegra30-devfreq.c
+++ b/drivers/devfreq/tegra30-devfreq.c
@@ -19,6 +19,8 @@ 
 #include <linux/reset.h>
 #include <linux/workqueue.h>
 
+#include <soc/tegra/fuse.h>
+
 #include "governor.h"
 
 #define ACTMON_GLB_STATUS					0x0
@@ -155,6 +157,7 @@  struct tegra_devfreq_device {
 
 struct tegra_devfreq {
 	struct devfreq		*devfreq;
+	struct opp_table	*opp_table;
 
 	struct reset_control	*reset;
 	struct clk		*clock;
@@ -612,34 +615,19 @@  static void tegra_actmon_stop(struct tegra_devfreq *tegra)
 static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
 				u32 flags)
 {
-	struct tegra_devfreq *tegra = dev_get_drvdata(dev);
-	struct devfreq *devfreq = tegra->devfreq;
 	struct dev_pm_opp *opp;
-	unsigned long rate;
-	int err;
+	int ret;
 
 	opp = devfreq_recommended_opp(dev, freq, flags);
 	if (IS_ERR(opp)) {
 		dev_err(dev, "Failed to find opp for %lu Hz\n", *freq);
 		return PTR_ERR(opp);
 	}
-	rate = dev_pm_opp_get_freq(opp);
-	dev_pm_opp_put(opp);
-
-	err = clk_set_min_rate(tegra->emc_clock, rate * KHZ);
-	if (err)
-		return err;
-
-	err = clk_set_rate(tegra->emc_clock, 0);
-	if (err)
-		goto restore_min_rate;
-
-	return 0;
 
-restore_min_rate:
-	clk_set_min_rate(tegra->emc_clock, devfreq->previous_freq);
+	ret = dev_pm_opp_set_bw(dev, opp);
+	dev_pm_opp_put(opp);
 
-	return err;
+	return ret;
 }
 
 static int tegra_devfreq_get_dev_status(struct device *dev,
@@ -655,7 +643,7 @@  static int tegra_devfreq_get_dev_status(struct device *dev,
 	stat->private_data = tegra;
 
 	/* The below are to be used by the other governors */
-	stat->current_frequency = cur_freq;
+	stat->current_frequency = cur_freq * KHZ;
 
 	actmon_dev = &tegra->devices[MCALL];
 
@@ -705,7 +693,12 @@  static int tegra_governor_get_target(struct devfreq *devfreq,
 		target_freq = max(target_freq, dev->target_freq);
 	}
 
-	*freq = target_freq;
+	/*
+	 * tegra-devfreq driver operates with KHz units, while OPP table
+	 * entries use Hz units. Hence we need to convert the units for the
+	 * devfreq core.
+	 */
+	*freq = target_freq * KHZ;
 
 	return 0;
 }
@@ -774,13 +767,22 @@  static struct devfreq_governor tegra_devfreq_governor = {
 
 static int tegra_devfreq_probe(struct platform_device *pdev)
 {
+	u32 hw_version = BIT(tegra_sku_info.soc_speedo_id);
 	struct tegra_devfreq_device *dev;
 	struct tegra_devfreq *tegra;
+	struct opp_table *opp_table;
 	struct devfreq *devfreq;
 	unsigned int i;
 	long rate;
 	int err;
 
+	/* legacy device-trees don't have OPP table and must be updated */
+	if (!device_property_present(&pdev->dev, "operating-points-v2")) {
+		dev_err(&pdev->dev,
+			"OPP table not found, please update your device tree\n");
+		return -ENODEV;
+	}
+
 	tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
 	if (!tegra)
 		return -ENOMEM;
@@ -822,11 +824,31 @@  static int tegra_devfreq_probe(struct platform_device *pdev)
 		return err;
 	}
 
+	tegra->opp_table = dev_pm_opp_get_opp_table(&pdev->dev);
+	err = PTR_ERR_OR_ZERO(tegra->opp_table);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to prepare OPP table: %d\n", err);
+		return err;
+	}
+
+	opp_table = dev_pm_opp_set_supported_hw(&pdev->dev, &hw_version, 1);
+	err = PTR_ERR_OR_ZERO(opp_table);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to set supported HW: %d\n", err);
+		goto put_table;
+	}
+
+	err = dev_pm_opp_of_add_table(&pdev->dev);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to add OPP table: %d\n", err);
+		goto put_hw;
+	}
+
 	err = clk_prepare_enable(tegra->clock);
 	if (err) {
 		dev_err(&pdev->dev,
 			"Failed to prepare and enable ACTMON clock\n");
-		return err;
+		goto remove_table;
 	}
 
 	err = reset_control_reset(tegra->reset);
@@ -850,23 +872,6 @@  static int tegra_devfreq_probe(struct platform_device *pdev)
 		dev->regs = tegra->regs + dev->config->offset;
 	}
 
-	for (rate = 0; rate <= tegra->max_freq * KHZ; rate++) {
-		rate = clk_round_rate(tegra->emc_clock, rate);
-
-		if (rate < 0) {
-			dev_err(&pdev->dev,
-				"Failed to round clock rate: %ld\n", rate);
-			err = rate;
-			goto remove_opps;
-		}
-
-		err = dev_pm_opp_add(&pdev->dev, rate / KHZ, 0);
-		if (err) {
-			dev_err(&pdev->dev, "Failed to add OPP: %d\n", err);
-			goto remove_opps;
-		}
-	}
-
 	platform_set_drvdata(pdev, tegra);
 
 	tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb;
@@ -882,7 +887,6 @@  static int tegra_devfreq_probe(struct platform_device *pdev)
 	}
 
 	tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock);
-	tegra_devfreq_profile.initial_freq /= KHZ;
 
 	devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile,
 				     "tegra_actmon", NULL);
@@ -902,6 +906,12 @@  static int tegra_devfreq_probe(struct platform_device *pdev)
 	reset_control_reset(tegra->reset);
 disable_clk:
 	clk_disable_unprepare(tegra->clock);
+remove_table:
+	dev_pm_opp_of_remove_table(&pdev->dev);
+put_hw:
+	dev_pm_opp_put_supported_hw(tegra->opp_table);
+put_table:
+	dev_pm_opp_put_opp_table(tegra->opp_table);
 
 	return err;
 }
@@ -913,11 +923,13 @@  static int tegra_devfreq_remove(struct platform_device *pdev)
 	devfreq_remove_device(tegra->devfreq);
 	devfreq_remove_governor(&tegra_devfreq_governor);
 
-	dev_pm_opp_remove_all_dynamic(&pdev->dev);
-
 	reset_control_reset(tegra->reset);
 	clk_disable_unprepare(tegra->clock);
 
+	dev_pm_opp_of_remove_table(&pdev->dev);
+	dev_pm_opp_put_supported_hw(tegra->opp_table);
+	dev_pm_opp_put_opp_table(tegra->opp_table);
+
 	return 0;
 }