[PATCH v2 1/4] thermal: Add driver for Armada 370/XP SoC thermal management

Zhang Rui rui.zhang at intel.com
Wed Mar 27 21:43:37 EDT 2013


On Tue, 2013-03-26 at 07:16 -0300, Ezequiel Garcia wrote:
> This driver supports both Armada 370 and Armada XP SoC
> thermal management controllers.
> 
> Armada 370 has a register to check a valid temperature, whereas
> Armada XP does not. Each has a different initialization (i.e. calibration)
> function. The temperature conversion formula is the same for both.
> 
> The controller present in each SoC have a very similar feature set,
> so it corresponds to have one driver to support both of them.
> 
> Although this driver may present similarities to Dove and Kirkwood
> thermal driver, the exact differences and coincidences are not fully
> known. For this reason, support is given through a separate driver.
> 
> Signed-off-by: Ezequiel Garcia <ezequiel.garcia at free-electrons.com>
> ---
> Changes from v1:
>  * Make armada_get_temp() more readable by reading the register
>    on a separate line, as requested by Durgadoss R.
> 
>  * Reorder Kconfig and Makefile entries, as requested by Andrew Lunn.
> 
>  .../devicetree/bindings/thermal/armada-thermal.txt |   22 ++
>  drivers/thermal/Kconfig                            |    8 +
>  drivers/thermal/Makefile                           |    1 +
>  drivers/thermal/armada_thermal.c                   |  236 ++++++++++++++++++++
>  4 files changed, 267 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/thermal/armada-thermal.txt
>  create mode 100644 drivers/thermal/armada_thermal.c
> 
> diff --git a/Documentation/devicetree/bindings/thermal/armada-thermal.txt b/Documentation/devicetree/bindings/thermal/armada-thermal.txt
> new file mode 100644
> index 0000000..fff93d5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/armada-thermal.txt
> @@ -0,0 +1,22 @@
> +* Marvell Armada 370/XP thermal management
> +
> +Required properties:
> +
> +- compatible:	Should be set to one of the following:
> +		marvell,armada370-thermal
> +		marvell,armadaxp-thermal
> +
> +- reg:		Device's register space.
> +		Two entries are expected, see the examples below.
> +		The first one is required for the sensor register;
> +		the second one is required for the control register
> +		to be used for sensor initialization (a.k.a. calibration).
> +
> +Example:
> +
> +	thermal at d0018300 {
> +		compatible = "marvell,armada370-thermal";
> +                reg = <0xd0018300 0x4
> +		       0xd0018304 0x4>;
> +		status = "okay";
> +	};
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index a764f16..9eddf74 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -144,6 +144,14 @@ config DB8500_THERMAL
>  	  created. Cooling devices can be bound to the trip points to cool this
>  	  thermal zone if trip points reached.
>  
> +config ARMADA_THERMAL
> +	tristate "Armada 370/XP thermal management"
> +	depends on ARCH_MVEBU
> +	depends on OF
> +	help
> +	  Enable this option if you want to have support for thermal management
> +	  controller present in Armada 370 and Armada XP SoC.
> +
>  config DB8500_CPUFREQ_COOLING
>  	tristate "DB8500 cpufreq cooling"
>  	depends on ARCH_U8500
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index d3a2b38..7f6509a 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -19,6 +19,7 @@ obj-$(CONFIG_KIRKWOOD_THERMAL)  += kirkwood_thermal.o
>  obj-$(CONFIG_EXYNOS_THERMAL)	+= exynos_thermal.o
>  obj-$(CONFIG_DOVE_THERMAL)  	+= dove_thermal.o
>  obj-$(CONFIG_DB8500_THERMAL)	+= db8500_thermal.o
> +obj-$(CONFIG_ARMADA_THERMAL)	+= armada_thermal.o
>  obj-$(CONFIG_DB8500_CPUFREQ_COOLING)	+= db8500_cpufreq_cooling.o
>  obj-$(CONFIG_INTEL_POWERCLAMP)	+= intel_powerclamp.o
>  
> diff --git a/drivers/thermal/armada_thermal.c b/drivers/thermal/armada_thermal.c
> new file mode 100644
> index 0000000..6743ec2
> --- /dev/null
> +++ b/drivers/thermal/armada_thermal.c
> @@ -0,0 +1,236 @@
> +/*
> + * Marvell Armada 370/XP thermal sensor driver
> + *
> + * Copyright (C) 2013 Marvell
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + */
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/of.h>
> +#include <linux/module.h>
> +#include <linux/delay.h>
> +#include <linux/platform_device.h>
> +#include <linux/of_device.h>
> +#include <linux/thermal.h>
> +
> +#define THERMAL_VALID_OFFSET		9
> +#define THERMAL_VALID_MASK		0x1
> +#define THERMAL_TEMP_OFFSET		10
> +#define THERMAL_TEMP_MASK		0x1ff
> +
> +/* Thermal Manager Control and Status Register */
> +#define PMU_TDC0_SW_RST_MASK		(0x1 << 1)
> +#define PMU_TM_DISABLE_OFFS		0
> +#define PMU_TM_DISABLE_MASK		(0x1 << PMU_TM_DISABLE_OFFS)
> +#define PMU_TDC0_REF_CAL_CNT_OFFS	11
> +#define PMU_TDC0_REF_CAL_CNT_MASK	(0x1ff << PMU_TDC0_REF_CAL_CNT_OFFS)
> +#define PMU_TDC0_OTF_CAL_MASK		(0x1 << 30)
> +#define PMU_TDC0_START_CAL_MASK		(0x1 << 25)
> +
> +struct armada_thermal_ops;
> +
> +/* Marvell EBU Thermal Sensor Dev Structure */
> +struct armada_thermal_priv {
> +	void __iomem *sensor;
> +	void __iomem *control;
> +	struct armada_thermal_ops *ops;
> +};
> +
> +struct armada_thermal_ops {
> +	/* Initialize the sensor */
> +	void (*init_sensor)(struct armada_thermal_priv *);
> +
> +	/* Test for a valid sensor value (optional) */
> +	bool (*is_valid)(struct armada_thermal_priv *);
> +};
> +
> +static void armadaxp_init_sensor(struct armada_thermal_priv *priv)
> +{
> +	unsigned long reg;
> +
> +	/* ??? */

what does this comment mean?

> +	reg = readl_relaxed(priv->control);
> +	reg |= PMU_TDC0_OTF_CAL_MASK;
> +	writel(reg, priv->control);
> +
> +	/* Reference calibration value */
> +	reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
> +	reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
> +	writel(reg, priv->control);
> +
> +	/* Reset the sensor */
> +	reg = readl_relaxed(priv->control);
> +	writel((reg | PMU_TDC0_SW_RST_MASK), priv->control);
> +
> +	writel(reg, priv->control);
> +
> +	/* Enable the sensor */
> +	reg = readl_relaxed(priv->sensor);
> +	reg &= ~PMU_TM_DISABLE_MASK;
> +	writel(reg, priv->sensor);
> +}
> +
> +static void armada370_init_sensor(struct armada_thermal_priv *priv)
> +{
> +	unsigned long reg;
> +
> +	/* ??? */

ditto.

thanks,
rui
> +	reg = readl_relaxed(priv->control);
> +	reg |= PMU_TDC0_OTF_CAL_MASK;
> +	writel(reg, priv->control);
> +
> +	/* Reference calibration value */
> +	reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
> +	reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
> +	writel(reg, priv->control);
> +
> +	/* ??? */
> +	reg &= ~PMU_TDC0_START_CAL_MASK;
> +	writel(reg, priv->control);
> +
> +	/* FIXME: Why do we need this delay? */
> +	mdelay(10);
> +}
> +
> +static bool armada_is_valid(struct armada_thermal_priv *priv)
> +{
> +	unsigned long reg = readl_relaxed(priv->sensor);
> +
> +	return (reg >> THERMAL_VALID_OFFSET) & THERMAL_VALID_MASK;
> +}
> +
> +static int armada_get_temp(struct thermal_zone_device *thermal,
> +			  unsigned long *temp)
> +{
> +	struct armada_thermal_priv *priv = thermal->devdata;
> +	unsigned long reg;
> +
> +	/* Valid check */
> +	if (priv->ops->is_valid && !priv->ops->is_valid(priv)) {
> +		dev_err(&thermal->device,
> +			"Temperature sensor reading not valid\n");
> +		return -EIO;
> +	}
> +
> +	reg = readl_relaxed(priv->sensor);
> +	reg = (reg >> THERMAL_TEMP_OFFSET) & THERMAL_TEMP_MASK;
> +	*temp = (3153000000UL - (10000000UL*reg)) / 13825;
> +	return 0;
> +}
> +
> +static struct thermal_zone_device_ops ops = {
> +	.get_temp = armada_get_temp,
> +};
> +
> +static const struct armada_thermal_ops armadaxp_ops = {
> +	.init_sensor = armadaxp_init_sensor,
> +};
> +
> +static const struct armada_thermal_ops armada370_ops = {
> +	.is_valid = armada_is_valid,
> +	.init_sensor = armada370_init_sensor,
> +};
> +
> +static const struct of_device_id armada_thermal_id_table[] = {
> +	{
> +		.compatible = "marvell,armadaxp-thermal",
> +		.data       = &armadaxp_ops,
> +	},
> +	{
> +		.compatible = "marvell,armada370-thermal",
> +		.data       = &armada370_ops,
> +	},
> +	{
> +		/* sentinel */
> +	},
> +};
> +MODULE_DEVICE_TABLE(of, armada_thermal_id_table);
> +
> +static int armada_thermal_probe(struct platform_device *pdev)
> +{
> +	struct thermal_zone_device *thermal;
> +	const struct of_device_id *match;
> +	struct armada_thermal_priv *priv;
> +	struct resource *res;
> +
> +	match = of_match_device(armada_thermal_id_table, &pdev->dev);
> +	if (!match)
> +		return -ENODEV;
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev, "Failed to get platform resource\n");
> +		return -ENODEV;
> +	}
> +
> +	priv->sensor = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(priv->sensor))
> +		return PTR_ERR(priv->sensor);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +	if (!res) {
> +		dev_err(&pdev->dev, "Failed to get platform resource\n");
> +		return -ENODEV;
> +	}
> +
> +	priv->control = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(priv->control))
> +		return PTR_ERR(priv->control);
> +
> +	priv->ops = (struct armada_thermal_ops *)match->data;
> +	priv->ops->init_sensor(priv);
> +
> +	thermal = thermal_zone_device_register("armada_thermal", 0, 0,
> +					       priv, &ops, NULL, 0, 0);
> +	if (IS_ERR(thermal)) {
> +		dev_err(&pdev->dev,
> +			"Failed to register thermal zone device\n");
> +		return PTR_ERR(thermal);
> +	}
> +
> +	platform_set_drvdata(pdev, thermal);
> +
> +	return 0;
> +}
> +
> +static int armada_thermal_exit(struct platform_device *pdev)
> +{
> +	struct thermal_zone_device *armada_thermal =
> +		platform_get_drvdata(pdev);
> +
> +	thermal_zone_device_unregister(armada_thermal);
> +	platform_set_drvdata(pdev, NULL);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver armada_thermal_driver = {
> +	.probe = armada_thermal_probe,
> +	.remove = armada_thermal_exit,
> +	.driver = {
> +		.name = "armada_thermal",
> +		.owner = THIS_MODULE,
> +		.of_match_table = of_match_ptr(armada_thermal_id_table),
> +	},
> +};
> +
> +module_platform_driver(armada_thermal_driver);
> +
> +MODULE_AUTHOR("Ezequiel Garcia <ezequiel.garcia at free-electrons.com>");
> +MODULE_DESCRIPTION("Armada 370/XP thermal driver");
> +MODULE_LICENSE("GPL v2");





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