[RFCv2,6/8] devfreq: Add imx-devfreq driver
diff mbox series

Message ID 5531b22cdcb056c66fc0a51b4c839df5d86049d0.1561707104.git.leonard.crestez@nxp.com
State RFC, archived
Headers show
Series
  • Add imx8mm bus frequency switching
Related show

Commit Message

Leonard Crestez June 28, 2019, 7:39 a.m. UTC
Add initial support for frequency switches on pieces of the imx
interconnect fabric.

Uses clk_set_min_rate so that other subsytems can also impose minimum
rate requests.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
---
 drivers/devfreq/Kconfig       |  10 +++
 drivers/devfreq/Makefile      |   1 +
 drivers/devfreq/imx-devfreq.c | 142 ++++++++++++++++++++++++++++++++++
 3 files changed, 153 insertions(+)
 create mode 100644 drivers/devfreq/imx-devfreq.c

Comments

Chanwoo Choi July 3, 2019, 1:31 a.m. UTC | #1
Hi Leonard,

On 19. 6. 28. 오후 4:39, Leonard Crestez wrote:
> Add initial support for frequency switches on pieces of the imx
> interconnect fabric.
> 
> Uses clk_set_min_rate so that other subsytems can also impose minimum
> rate requests.
> 
> Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
> ---
>  drivers/devfreq/Kconfig       |  10 +++
>  drivers/devfreq/Makefile      |   1 +
>  drivers/devfreq/imx-devfreq.c | 142 ++++++++++++++++++++++++++++++++++
>  3 files changed, 153 insertions(+)
>  create mode 100644 drivers/devfreq/imx-devfreq.c
> 
> diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
> index f3b242987fd9..3a7c6265ca2f 100644
> --- a/drivers/devfreq/Kconfig
> +++ b/drivers/devfreq/Kconfig
> @@ -90,10 +90,20 @@ config ARM_EXYNOS_BUS_DEVFREQ
>  	  Each memory bus group could contain many memoby bus block. It reads
>  	  PPMU counters of memory controllers by using DEVFREQ-event device
>  	  and adjusts the operating frequencies and voltages with OPP support.
>  	  This does not yet operate with optimal voltages.
>  
> +config ARM_IMX_DEVFREQ
> +	tristate "i.MX DEVFREQ Driver"
> +	depends on ARCH_MXC

You don't need to add 'COMPILE_TEST' as following?
	depends on ARCH_MXC || COMPILE_TEST

> +	select DEVFREQ_GOV_USERSPACE
> +	select PM_OPP
> +	help
> +	  This adds the DEVFREQ driver for the Tegra family of SoCs.
> +	  It reads ACTMON counters of memory controllers and adjusts the
> +	  operating frequencies and voltages with OPP support.

Maybe, you referred to the description of ARM_TEGRA_DEVFREQ.
You have to modify it according to the role of IMX_DEVFREQ.

> +
>  config ARM_TEGRA_DEVFREQ
>  	tristate "NVIDIA Tegra30/114/124/210 DEVFREQ Driver"
>  	depends on ARCH_TEGRA_3x_SOC || ARCH_TEGRA_114_SOC || \
>  		ARCH_TEGRA_132_SOC || ARCH_TEGRA_124_SOC || \
>  		ARCH_TEGRA_210_SOC || \
> diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
> index 338ae8440db6..c2463ed4c934 100644
> --- a/drivers/devfreq/Makefile
> +++ b/drivers/devfreq/Makefile
> @@ -7,10 +7,11 @@ obj-$(CONFIG_DEVFREQ_GOV_POWERSAVE)	+= governor_powersave.o
>  obj-$(CONFIG_DEVFREQ_GOV_USERSPACE)	+= governor_userspace.o
>  obj-$(CONFIG_DEVFREQ_GOV_PASSIVE)	+= governor_passive.o
>  
>  # DEVFREQ Drivers
>  obj-$(CONFIG_ARM_EXYNOS_BUS_DEVFREQ)	+= exynos-bus.o
> +obj-$(CONFIG_ARM_IMX_DEVFREQ)		+= imx-devfreq.o
>  obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ)	+= rk3399_dmc.o
>  obj-$(CONFIG_ARM_TEGRA_DEVFREQ)		+= tegra30-devfreq.o
>  obj-$(CONFIG_ARM_TEGRA20_DEVFREQ)	+= tegra20-devfreq.o
>  
>  # DEVFREQ Event Drivers
> diff --git a/drivers/devfreq/imx-devfreq.c b/drivers/devfreq/imx-devfreq.c
> new file mode 100644
> index 000000000000..aa8868d32f22
> --- /dev/null
> +++ b/drivers/devfreq/imx-devfreq.c
> @@ -0,0 +1,142 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2019 NXP
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/devfreq.h>
> +#include <linux/devfreq-event.h>
> +#include <linux/device.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/pm_opp.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +struct imx_devfreq {
> +	struct devfreq_dev_profile profile;
> +	struct devfreq *devfreq;
> +	struct clk *clk;
> +};
> +
> +static int imx_devfreq_target(struct device *dev, unsigned long *freq, u32 flags)
> +{
> +	struct imx_devfreq *priv = dev_get_drvdata(dev);
> +	struct dev_pm_opp *new_opp;
> +	unsigned long new_freq;
> +	int ret;
> +
> +	new_opp = devfreq_recommended_opp(dev, freq, flags);
> +	if (IS_ERR(new_opp)) {
> +		ret = PTR_ERR(new_opp);
> +		dev_err(dev, "failed to get recommended opp: %d\n", ret);
> +		return ret;
> +	}
> +	new_freq = dev_pm_opp_get_freq(new_opp);
> +	dev_pm_opp_put(new_opp);
> +
> +	ret = clk_set_min_rate(priv->clk, new_freq);
> +        if (ret)

Fix the indentation.

> +		return ret;
> +
> +	ret = clk_set_rate(priv->clk, 0);
> +	if (ret) {
> +		clk_set_min_rate(priv->clk, priv->devfreq->previous_freq);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int imx_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
> +{
> +	struct imx_devfreq *priv = dev_get_drvdata(dev);
> +
> +	*freq = clk_get_rate(priv->clk);
> +
> +	return 0;
> +}
> +
> +static int imx_devfreq_get_dev_status(struct device *dev,
> +		struct devfreq_dev_status *stat)
> +{
> +	struct imx_devfreq *priv = dev_get_drvdata(dev);
> +
> +	stat->busy_time = 0;
> +	stat->total_time = 0;
> +	stat->current_frequency = clk_get_rate(priv->clk);
> +
> +	return 0;
> +}
> +
> +static void imx_devfreq_exit(struct device *dev)
> +{
> +	return dev_pm_opp_of_remove_table(dev);
> +}
> +
> +static int imx_devfreq_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct imx_devfreq *priv;
> +	int ret;
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->clk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(priv->devfreq)) {
> +		ret = PTR_ERR(priv->devfreq);
> +		dev_err(dev, "failed to fetch clk: %d\n", ret);
> +		return ret;
> +	}
> +	platform_set_drvdata(pdev, priv);
> +
> +	ret = dev_pm_opp_of_add_table(dev);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to get OPP table\n");
> +		return ret;
> +	}
> +
> +	priv->profile.polling_ms = 1000;
> +	priv->profile.target = imx_devfreq_target;
> +	priv->profile.get_dev_status = imx_devfreq_get_dev_status;
> +	priv->profile.exit = imx_devfreq_exit;
> +	priv->profile.get_cur_freq = imx_devfreq_get_cur_freq;
> +	priv->profile.initial_freq = clk_get_rate(priv->clk);
> +
> +	priv->devfreq = devm_devfreq_add_device(dev, &priv->profile,
> +						DEVFREQ_GOV_USERSPACE,
> +						NULL);
> +	if (IS_ERR(priv->devfreq)) {
> +		ret = PTR_ERR(priv->devfreq);
> +		dev_err(dev, "failed to add devfreq device: %d\n", ret);
> +		goto err_remove_table;
> +	}
> +
> +	return 0;
> +
> +err_remove_table:
> +	dev_pm_opp_of_remove_table(dev);
> +	return ret;
> +}
> +
> +static const struct of_device_id imx_devfreq_of_match[] = {
> +	{ .compatible = "fsl,imx8mm-ddrc", },
> +	{ .compatible = "fsl,imx8mm-noc", },
> +	{ .compatible = "fsl,imx8mm-nic", },
> +	{ /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, imx_devfreq_of_match);
> +
> +static struct platform_driver imx_devfreq_platdrv = {
> +	.probe		= imx_devfreq_probe,
> +	.driver = {
> +		.name	= "devfreq-imx",
> +		.of_match_table = of_match_ptr(imx_devfreq_of_match),
> +	},
> +};
> +module_platform_driver(imx_devfreq_platdrv);
> +
> +MODULE_DESCRIPTION("Generic i.MX bus frequency driver");
> +MODULE_LICENSE("GPL v2");
> 

Why don't you add the author information?

And when you are sending the patch, you better
to use get_maintainer.pl script to contain
the related all maintainers/reviewers.

Patch
diff mbox series

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index f3b242987fd9..3a7c6265ca2f 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -90,10 +90,20 @@  config ARM_EXYNOS_BUS_DEVFREQ
 	  Each memory bus group could contain many memoby bus block. It reads
 	  PPMU counters of memory controllers by using DEVFREQ-event device
 	  and adjusts the operating frequencies and voltages with OPP support.
 	  This does not yet operate with optimal voltages.
 
+config ARM_IMX_DEVFREQ
+	tristate "i.MX DEVFREQ Driver"
+	depends on ARCH_MXC
+	select DEVFREQ_GOV_USERSPACE
+	select PM_OPP
+	help
+	  This adds the DEVFREQ driver for the Tegra family of SoCs.
+	  It reads ACTMON counters of memory controllers and adjusts the
+	  operating frequencies and voltages with OPP support.
+
 config ARM_TEGRA_DEVFREQ
 	tristate "NVIDIA Tegra30/114/124/210 DEVFREQ Driver"
 	depends on ARCH_TEGRA_3x_SOC || ARCH_TEGRA_114_SOC || \
 		ARCH_TEGRA_132_SOC || ARCH_TEGRA_124_SOC || \
 		ARCH_TEGRA_210_SOC || \
diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
index 338ae8440db6..c2463ed4c934 100644
--- a/drivers/devfreq/Makefile
+++ b/drivers/devfreq/Makefile
@@ -7,10 +7,11 @@  obj-$(CONFIG_DEVFREQ_GOV_POWERSAVE)	+= governor_powersave.o
 obj-$(CONFIG_DEVFREQ_GOV_USERSPACE)	+= governor_userspace.o
 obj-$(CONFIG_DEVFREQ_GOV_PASSIVE)	+= governor_passive.o
 
 # DEVFREQ Drivers
 obj-$(CONFIG_ARM_EXYNOS_BUS_DEVFREQ)	+= exynos-bus.o
+obj-$(CONFIG_ARM_IMX_DEVFREQ)		+= imx-devfreq.o
 obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ)	+= rk3399_dmc.o
 obj-$(CONFIG_ARM_TEGRA_DEVFREQ)		+= tegra30-devfreq.o
 obj-$(CONFIG_ARM_TEGRA20_DEVFREQ)	+= tegra20-devfreq.o
 
 # DEVFREQ Event Drivers
diff --git a/drivers/devfreq/imx-devfreq.c b/drivers/devfreq/imx-devfreq.c
new file mode 100644
index 000000000000..aa8868d32f22
--- /dev/null
+++ b/drivers/devfreq/imx-devfreq.c
@@ -0,0 +1,142 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 NXP
+ */
+
+#include <linux/clk.h>
+#include <linux/devfreq.h>
+#include <linux/devfreq-event.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+struct imx_devfreq {
+	struct devfreq_dev_profile profile;
+	struct devfreq *devfreq;
+	struct clk *clk;
+};
+
+static int imx_devfreq_target(struct device *dev, unsigned long *freq, u32 flags)
+{
+	struct imx_devfreq *priv = dev_get_drvdata(dev);
+	struct dev_pm_opp *new_opp;
+	unsigned long new_freq;
+	int ret;
+
+	new_opp = devfreq_recommended_opp(dev, freq, flags);
+	if (IS_ERR(new_opp)) {
+		ret = PTR_ERR(new_opp);
+		dev_err(dev, "failed to get recommended opp: %d\n", ret);
+		return ret;
+	}
+	new_freq = dev_pm_opp_get_freq(new_opp);
+	dev_pm_opp_put(new_opp);
+
+	ret = clk_set_min_rate(priv->clk, new_freq);
+        if (ret)
+		return ret;
+
+	ret = clk_set_rate(priv->clk, 0);
+	if (ret) {
+		clk_set_min_rate(priv->clk, priv->devfreq->previous_freq);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int imx_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+	struct imx_devfreq *priv = dev_get_drvdata(dev);
+
+	*freq = clk_get_rate(priv->clk);
+
+	return 0;
+}
+
+static int imx_devfreq_get_dev_status(struct device *dev,
+		struct devfreq_dev_status *stat)
+{
+	struct imx_devfreq *priv = dev_get_drvdata(dev);
+
+	stat->busy_time = 0;
+	stat->total_time = 0;
+	stat->current_frequency = clk_get_rate(priv->clk);
+
+	return 0;
+}
+
+static void imx_devfreq_exit(struct device *dev)
+{
+	return dev_pm_opp_of_remove_table(dev);
+}
+
+static int imx_devfreq_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct imx_devfreq *priv;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(priv->devfreq)) {
+		ret = PTR_ERR(priv->devfreq);
+		dev_err(dev, "failed to fetch clk: %d\n", ret);
+		return ret;
+	}
+	platform_set_drvdata(pdev, priv);
+
+	ret = dev_pm_opp_of_add_table(dev);
+	if (ret < 0) {
+		dev_err(dev, "failed to get OPP table\n");
+		return ret;
+	}
+
+	priv->profile.polling_ms = 1000;
+	priv->profile.target = imx_devfreq_target;
+	priv->profile.get_dev_status = imx_devfreq_get_dev_status;
+	priv->profile.exit = imx_devfreq_exit;
+	priv->profile.get_cur_freq = imx_devfreq_get_cur_freq;
+	priv->profile.initial_freq = clk_get_rate(priv->clk);
+
+	priv->devfreq = devm_devfreq_add_device(dev, &priv->profile,
+						DEVFREQ_GOV_USERSPACE,
+						NULL);
+	if (IS_ERR(priv->devfreq)) {
+		ret = PTR_ERR(priv->devfreq);
+		dev_err(dev, "failed to add devfreq device: %d\n", ret);
+		goto err_remove_table;
+	}
+
+	return 0;
+
+err_remove_table:
+	dev_pm_opp_of_remove_table(dev);
+	return ret;
+}
+
+static const struct of_device_id imx_devfreq_of_match[] = {
+	{ .compatible = "fsl,imx8mm-ddrc", },
+	{ .compatible = "fsl,imx8mm-noc", },
+	{ .compatible = "fsl,imx8mm-nic", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, imx_devfreq_of_match);
+
+static struct platform_driver imx_devfreq_platdrv = {
+	.probe		= imx_devfreq_probe,
+	.driver = {
+		.name	= "devfreq-imx",
+		.of_match_table = of_match_ptr(imx_devfreq_of_match),
+	},
+};
+module_platform_driver(imx_devfreq_platdrv);
+
+MODULE_DESCRIPTION("Generic i.MX bus frequency driver");
+MODULE_LICENSE("GPL v2");