[PATCH v2 1/4] thermal: Add driver for Armada 370/XP SoC thermal management
Ezequiel Garcia
ezequiel.garcia at free-electrons.com
Wed Mar 27 23:43:34 EDT 2013
On Thu, Mar 28, 2013 at 09:43:37AM +0800, Zhang Rui wrote:
> 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?
>
It means I'm not sure entirely sure what the below code does.
Maybe I should remove it?
> > + reg = readl_relaxed(priv->control);
> > + reg |= PMU_TDC0_OTF_CAL_MASK;
> > + writel(reg, priv->control);
> > +
Thanks for the review,
--
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com
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