Re: [PATCH v6] ARM: imx: Add basic imx6q thermal driver

From: Rob Lee
Date: Wed Jun 27 2012 - 09:35:50 EST

On Tue, Jun 26, 2012 at 11:51 PM, Robert Lee <rob.lee@xxxxxxxxxx> wrote:
> Add imx anatop peripheral thermal driver and use it for imx6q builds.
> This driver hooks into the linux thermal framework which provides a
> sysfs interface for temperature readings and other information and
> a mechanism to shutdown the system upon crossing a critical
> temperature trip point.
>
> Only the sysfs interface and a critcial trip are supported by this
> patch and not any active trip points or cooling devices.
>
> The thermal driver is defaulted to be enabled which required the
> anatopmfd driver to be defaulted to enabled.
>
> Signed-off-by: Robert Lee <rob.lee@xxxxxxxxxx>
> ---
> arch/arm/boot/dts/imx6q.dtsi | 5 +
> drivers/mfd/Kconfig | 1 +
> drivers/thermal/Kconfig | 9 +
> drivers/thermal/Makefile | 1 +
> drivers/thermal/imx_anatop_thermal.c | 465 ++++++++++++++++++++++++++++++++++
> 5 files changed, 481 insertions(+)
> create mode 100644 drivers/thermal/imx_anatop_thermal.c
>
> diff --git a/arch/arm/boot/dts/imx6q.dtsi b/arch/arm/boot/dts/imx6q.dtsi
> index d026f30..b53a16a 100644
> --- a/arch/arm/boot/dts/imx6q.dtsi
> +++ b/arch/arm/boot/dts/imx6q.dtsi
> @@ -449,6 +449,10 @@
> anatop-min-voltage = <725000>;
> anatop-max-voltage = <1450000>;
> };
> +
> + thermal {
> + compatible ="fsl,anatop-thermal";
> + };
> };
>
> usbphy@020c9000 { /* USBPHY1 */
> @@ -666,6 +670,7 @@
> };
>
> ocotp@021bc000 {
> + compatible = "fsl,imx6q-ocotp";
> reg = <0x021bc000 0x4000>;
> };
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index e129c82..552fae3 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -915,6 +915,7 @@ config MFD_STA2X11
> config MFD_ANATOP
> bool "Support for Freescale i.MX on-chip ANATOP controller"
> depends on SOC_IMX6Q
> + default y
> help
> Select this option to enable Freescale i.MX on-chip ANATOP
> MFD controller. This controller embeds regulator and
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 04c6796..a35a35e 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -30,6 +30,15 @@ config CPU_THERMAL
> and not the ACPI interface.
> If you want this support, you should say Y or M here.
>
> +config IMX_ANATOP_THERMAL
> + bool "imx anatop soc thermal driver"
> + depends on MFD_ANATOP && CPU_THERMAL

I forgot to replace "CPU_THERMAL" with "THERMAL"

> + default y
> + help
> + Enable the on-chip temperature sensor and register the linux thermal
> + framework to provide SoC temperature data to sysfs and a basic
> + shutdown mechanism to prevent the SoC from overheating.
> +
> config SPEAR_THERMAL
> bool "SPEAr thermal sensor driver"
> depends on THERMAL
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 4636e35..4dd4570 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_THERMAL) += thermal_sys.o
> obj-$(CONFIG_CPU_THERMAL) += cpu_cooling.o
> obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o
> obj-$(CONFIG_EXYNOS_THERMAL) += exynos_thermal.o
> +obj-$(CONFIG_IMX_ANATOP_THERMAL) += imx_anatop_thermal.o
> diff --git a/drivers/thermal/imx_anatop_thermal.c b/drivers/thermal/imx_anatop_thermal.c
> new file mode 100644
> index 0000000..a932fe8
> --- /dev/null
> +++ b/drivers/thermal/imx_anatop_thermal.c
> @@ -0,0 +1,465 @@
> +/*
> + * Copyright 2012 Freescale Semiconductor, Inc.
> + * Copyright 2012 Linaro Ltd.
> + *
> + * The code contained herein is licensed under the GNU General Public
> + * License. You may obtain a copy of the GNU General Public License
> + * Version 2 or later at the following locations:
> + *
> + * http://www.opensource.org/licenses/gpl-license.html
> + * http://www.gnu.org/copyleft/gpl.html
> + */
> +
> +/*
> + * Thermal driver for i.MX anatop systems. Implented by hooking in to the
> + * linux thermal framework.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dmi.h>
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/anatop.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/smp.h>
> +#include <linux/slab.h>
> +#include <linux/syscalls.h>
> +#include <linux/thermal.h>
> +#include <linux/types.h>
> +
> +/* register define of anatop */
> +#define HW_ANADIG_ANA_MISC0 0x00000150
> +#define HW_ANADIG_ANA_MISC0_SET 0x00000154
> +#define HW_ANADIG_ANA_MISC0_CLR 0x00000158
> +#define HW_ANADIG_ANA_MISC0_TOG 0x0000015c
> +#define BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF 0x00000008
> +
> +#define HW_ANADIG_TEMPSENSE0 0x00000180
> +#define HW_ANADIG_TEMPSENSE0_SET 0x00000184
> +#define HW_ANADIG_TEMPSENSE0_CLR 0x00000188
> +#define HW_ANADIG_TEMPSENSE0_TOG 0x0000018c
> +
> +#define BP_ANADIG_TEMPSENSE0_TEMP_VALUE 8
> +#define BM_ANADIG_TEMPSENSE0_TEMP_VALUE 0x000FFF00
> +#define BM_ANADIG_TEMPSENSE0_FINISHED 0x00000004
> +#define BM_ANADIG_TEMPSENSE0_MEASURE_TEMP 0x00000002
> +#define BM_ANADIG_TEMPSENSE0_POWER_DOWN 0x00000001
> +
> +#define HW_ANADIG_TEMPSENSE1 0x00000190
> +#define HW_ANADIG_TEMPSENSE1_SET 0x00000194
> +#define HW_ANADIG_TEMPSENSE1_CLR 0x00000198
> +#define BP_ANADIG_TEMPSENSE1_MEASURE_FREQ 0
> +#define BM_ANADIG_TEMPSENSE1_MEASURE_FREQ 0x0000FFFF
> +
> +#define HW_OCOTP_ANA1 0x000004E0
> +
> +#define IMX_THERMAL_POLLING_FREQUENCY_MS 1000
> +
> +#define IMX_ANATOP_TS_NOISE_MARGIN 3000 /* in millicelsius */
> +#define IMX_ANATOP_TS_NOISE_COUNT 3
> +
> +/* anatop temperature sensor data */
> +struct imx_anatop_tsdata {
> + int c1, c2;
> + u32 noise_margin; /* in millicelsius */
> + int last_temp; /* in millicelsius */
> + /*
> + * When filtering noise, if consecutive measurements are each higher
> + * up to consec_high_limit times, assume changing temperature readings
> + * to be valid and not noise.
> + */
> + u32 consec_high_limit;
> + bool handle_suspend;
> + struct anatop *anatopmfd;
> +
> +};
> +
> +struct imx_anatop_thdata {
> + struct thermal_zone_device *tzdev;
> + struct imx_anatop_tsdata sensor_data;
> + struct thermal_zone_device_ops dev_ops;
> + unsigned int crit_temp_level;
> + void __iomem *ocotp_base;
> +};
> +
> +static inline int anatop_get_temp(int *temp, struct thermal_zone_device *tzdev)
> +{
> + unsigned int n_meas;
> + unsigned int reg;
> + struct imx_anatop_tsdata *sd;
> +
> + sd = &((struct imx_anatop_thdata *)tzdev->devdata)->sensor_data;
> +
> +
> + do {
> + /*
> + * Every time we measure the temperature, we will power on the
> + * temperature sensor, enable measurements, take a reading,
> + * disable measurements, power off the temperature sensor.
> + */
> + sd->handle_suspend = false;
> +
> + anatop_write_reg(sd->anatopmfd, HW_ANADIG_TEMPSENSE0, 0,
> + BM_ANADIG_TEMPSENSE0_POWER_DOWN);
> + anatop_write_reg(sd->anatopmfd, HW_ANADIG_TEMPSENSE0,
> + BM_ANADIG_TEMPSENSE0_MEASURE_TEMP,
> + BM_ANADIG_TEMPSENSE0_MEASURE_TEMP);
> + /*
> + * According to the anatop temp sensor designers, it may require
> + * up to ~17us to complete a measurement (imx6q).
> + * But this timing isn't checked on every part nor is it
> + * specified in the datasheet, so sleeping at least 1ms should
> + * provide plenty of time. Sleeping longer than 1ms is ok so no
> + * need for usleep_range */
> + msleep(1);
> +
> + reg = anatop_read_reg(sd->anatopmfd, HW_ANADIG_TEMPSENSE0);
> +
> + anatop_write_reg(sd->anatopmfd, HW_ANADIG_TEMPSENSE0, 0,
> + BM_ANADIG_TEMPSENSE0_MEASURE_TEMP);
> + anatop_write_reg(sd->anatopmfd, HW_ANADIG_TEMPSENSE0,
> + BM_ANADIG_TEMPSENSE0_POWER_DOWN,
> + BM_ANADIG_TEMPSENSE0_POWER_DOWN);
> +
> + /* if we had a suspend and resume event, we will re-take the reading */
> + } while (sd->handle_suspend);
> +
> + if (!(reg & BM_ANADIG_TEMPSENSE0_FINISHED) &&
> + (reg & BM_ANADIG_TEMPSENSE0_TEMP_VALUE)) {
> + dev_dbg(&tzdev->device,
> + "Temp sensor error: reading never finished");
> + return -EAGAIN;
> + }
> +
> + n_meas = (reg & BM_ANADIG_TEMPSENSE0_TEMP_VALUE)
> + >> BP_ANADIG_TEMPSENSE0_TEMP_VALUE;
> +
> + /* See anatop_process_ts_fuse_data() for forumla derivation. */
> + *temp = sd->c2 + (sd->c1 * n_meas);
> +
> + dev_dbg(&tzdev->device, "Temperature: %d\n", *temp / 1000);
> + return 0;
> +}
> +
> +static int th_sys_get_temp(struct thermal_zone_device *tzdev,
> + unsigned long *temp)
> +{
> + int i, total = 0, tmp = 0;
> + const u8 loop = 5;
> + u32 consec_high = 0;
> +
> + struct imx_anatop_tsdata *sd;
> +
> + sd = &((struct imx_anatop_thdata *)tzdev->devdata)->sensor_data;
> +
> + /*
> + * Measure temperature and handle noise
> + *
> + * While the anatop temperature sensor is designed to minimize being
> + * affected by system noise, it's safest to run sanity checks and
> + * perform any necessary filtering, if a noise_margin has been defined.
> + */
> + for (i = 0; (sd->noise_margin) && (i < loop); i++) {
> + /*
> + * We expect the sensor reading to be successful, but if for
> + * unknow reason it is not, use the data from the last
> + * successful reading
> + */
> + if (anatop_get_temp(&tmp, tzdev)) {
> + tmp = sd->last_temp;
> + continue;
> + }
> +
> + if ((abs(tmp - sd->last_temp) <= sd->noise_margin) ||
> + (consec_high >= sd->consec_high_limit)) {
> + sd->last_temp = tmp;
> + i = 0;
> + break;
> + }
> + if (tmp > sd->last_temp)
> + consec_high++;
> +
> + /*
> + * ignore first measurement as the previous measurement was
> + * a long time ago.
> + */
> + if (i)
> + total += tmp;
> +
> + sd->last_temp = tmp;
> + }
> +
> + if (sd->noise_margin && i)
> + tmp = total / (loop - 1);
> +
> + /*
> + * The thermal framework code stores temperature in unsigned long. Also,
> + * it has references to "millicelsius" which limits the lowest
> + * temperature possible (compared to Kelvin).
> + */
> + if (tmp > 0)
> + *temp = tmp;
> + else
> + *temp = 0;
> + return 0;
> +}
> +
> +static int th_sys_get_mode(struct thermal_zone_device *tzdev,
> + enum thermal_device_mode *mode)
> +{
> + *mode = THERMAL_DEVICE_ENABLED;
> + return 0;
> +}
> +
> +static int th_sys_get_trip_type(struct thermal_zone_device *tzdev, int trip,
> + enum thermal_trip_type *type)
> +{
> + *type = THERMAL_TRIP_CRITICAL;
> + return 0;
> +}
> +
> +static int th_sys_get_crit_temp(struct thermal_zone_device *tzdev,
> + unsigned long *temp)
> +{
> + struct imx_anatop_thdata *p;
> +
> + p = (struct imx_anatop_thdata *)tzdev->devdata;
> + *temp = p->crit_temp_level;
> + return 0;
> +}
> +
> +static int th_sys_get_trip_temp(struct thermal_zone_device *tzdev, int trip,
> + unsigned long *temp)
> +{
> + /* only a critical trip point is supported, for now. */
> + return th_sys_get_crit_temp(tzdev, temp);
> +}
> +
> +static int __devinit anatop_process_ts_fuse_data(unsigned int fuse_data,
> + struct imx_anatop_thdata *thermal_data)
> +{
> + int t1, t2, n1, n2;
> + struct imx_anatop_tsdata *sd = &thermal_data->sensor_data;
> + struct thermal_zone_device *tzdev = thermal_data->tzdev;
> +
> +
> + if (fuse_data == 0 || fuse_data == 0xffffffff) {
> + dev_warn(&tzdev->device, "WARNING: Disabling CPU thermal "
> + "protection (invalid calibration value of %x detected\n"
> + , fuse_data);
> + return -EINVAL;
> + }
> +
> + /*
> + * Fuse data layout:
> + * [31:20] sensor value @ 25C
> + * [19:8] sensor value of hot
> + * [7:0] hot temperature value
> + */
> + n1 = fuse_data >> 20;
> + n2 = (fuse_data & 0xfff00) >> 8;
> + t2 = fuse_data & 0xff;
> + t1 = 25; /* t1 always 25C */
> +
> + dev_dbg(&tzdev->device, " -- temperature sensor calibration data --\n");
> + dev_dbg(&tzdev->device, "HW_OCOTP_ANA1: %x\n", fuse_data);
> + dev_dbg(&tzdev->device, "n1: %d\nn2: %d\nt1: %d\nt2: %d\n", n1, n2, t1,
> + t2);
> +
> + /*
> + * Derived from linear interpolation,
> + * Tmeas = T2 + (Nmeas - N2) * (T1 - T2) / (N1 - N2)
> + * We want to reduce this down to the minimum computation necessary
> + * for each temperature read. Also, we want Tmeas in millicelsius
> + * and we don't want to lose precision from integer division. So...
> + * milli_Tmeas = 1000 * T2 + 1000 * (Nmeas - N2) * (T1 - T2) / (N1 - N2)
> + * Let constant c1 = 1000 * (T1 - T2) / (N1 - N2)
> + * milli_Tmeas = (1000 * T2) + c1 * (Nmeas - N2)
> + * milli_Tmeas = (1000 * T2) + (c1 * Nmeas) - (c1 * N2)
> + * Let constant c2 = (1000 * T2) - (c1 * N2)
> + * milli_Tmeas = c2 + (c1 * Nmeas)
> + */
> + sd->c1 = (1000 * (t1 - t2)) / (n1 - n2);
> + sd->c2 = (1000 * t2) - (sd->c1 * n2);
> +
> + dev_dbg(&tzdev->device, "c1: %i\n", sd->c1);
> + dev_dbg(&tzdev->device, "c2: %i\n", sd->c2);
> + return 0;
> +}
> +
> +static int anatop_thermal_suspend(struct platform_device *pdev,
> + pm_message_t state)
> +{
> + struct imx_anatop_thdata *dd = platform_get_drvdata(pdev);
> + struct imx_anatop_tsdata *sd = &dd->sensor_data;
> +
> + /* power off the sensor during suspend */
> + anatop_write_reg(sd->anatopmfd, HW_ANADIG_TEMPSENSE0, 0,
> + BM_ANADIG_TEMPSENSE0_MEASURE_TEMP);
> +
> + anatop_write_reg(sd->anatopmfd, HW_ANADIG_TEMPSENSE0,
> + BM_ANADIG_TEMPSENSE0_POWER_DOWN,
> + BM_ANADIG_TEMPSENSE0_POWER_DOWN);
> + return 0;
> +}
> +
> +static int anatop_thermal_resume(struct platform_device *pdev)
> +{
> + struct imx_anatop_thdata *dd = platform_get_drvdata(pdev);
> + struct imx_anatop_tsdata *sd = &dd->sensor_data;
> +
> + sd->handle_suspend = true;
> + return 0;
> +}
> +
> +static int __devexit anatop_thermal_remove(struct platform_device *pdev)
> +{
> + struct imx_anatop_thdata *dd = platform_get_drvdata(pdev);
> +
> + if (dd && dd->tzdev)
> + thermal_zone_device_unregister(dd->tzdev);
> +
> + if (dd->ocotp_base)
> + iounmap(dd->ocotp_base);
> +
> + dev_info(&pdev->dev, "imx thermal management unregistered\n");
> + return 0;
> +}
> +
> +static int __devinit anatop_thermal_probe(struct platform_device *pdev)
> +{
> + unsigned int fuse_data;
> + void __iomem *ocotp_base;
> + struct device_node *np_ocotp, *np_thermal;
> + static struct imx_anatop_thdata *therm_data;
> + struct anatop *anatopmfd = dev_get_drvdata(pdev->dev.parent);
> +
> + struct imx_anatop_tsdata *sd;
> + int ret;
> +
> + np_ocotp = of_find_compatible_node(NULL, NULL, "fsl,imx6q-ocotp");
> + np_thermal = pdev->dev.of_node;
> +
> + if (!(np_ocotp && np_thermal && anatopmfd))
> + return 0;
> +
> + ocotp_base = of_iomap(np_ocotp, 0);
> +
> + if (!ocotp_base) {
> + dev_err(&pdev->dev, "Could not retrieve ocotp-base\n");
> + ret = -ENXIO;
> + goto err_unregister;
> + }
> +
> + fuse_data = readl_relaxed(ocotp_base + HW_OCOTP_ANA1);
> +
> + therm_data = devm_kzalloc(&pdev->dev, sizeof(struct imx_anatop_thdata),
> + GFP_KERNEL);
> +
> +
> + if (!therm_data) {
> + ret = -ENOMEM;
> + goto err_unregister;
> + }
> +
> + therm_data->dev_ops.get_temp = th_sys_get_temp;
> + therm_data->dev_ops.get_mode = th_sys_get_mode;
> + therm_data->dev_ops.get_trip_type = th_sys_get_trip_type;
> + therm_data->dev_ops.get_trip_temp = th_sys_get_trip_temp;
> + therm_data->dev_ops.get_crit_temp = th_sys_get_crit_temp;
> +
> + /*
> + * max die temp on imx parts using anatop is 105C, let's give some
> + * cushion for noise and possible temperature rise between measurements.
> + */
> + therm_data->crit_temp_level = 100000; /* in millicelsius */
> +
> + sd = &therm_data->sensor_data;
> + sd->noise_margin = IMX_ANATOP_TS_NOISE_MARGIN;
> + sd->consec_high_limit = IMX_ANATOP_TS_NOISE_COUNT;
> + sd->anatopmfd = anatopmfd;
> +
> + platform_set_drvdata(pdev, therm_data);
> +
> + ret = anatop_process_ts_fuse_data(fuse_data, therm_data);
> +
> + if (ret) {
> + dev_err(&pdev->dev, "Invalid temperature calibration data.\n");
> + goto err_unregister;
> + }
> +
> + /* Make sure sensor is in known good state for measurements */
> + anatop_write_reg(anatopmfd, HW_ANADIG_TEMPSENSE0, 0,
> + BM_ANADIG_TEMPSENSE0_POWER_DOWN);
> +
> + anatop_write_reg(anatopmfd, HW_ANADIG_TEMPSENSE0, 0,
> + BM_ANADIG_TEMPSENSE0_MEASURE_TEMP);
> +
> + anatop_write_reg(anatopmfd, HW_ANADIG_TEMPSENSE1, 0,
> + BM_ANADIG_TEMPSENSE1_MEASURE_FREQ);
> +
> + anatop_write_reg(anatopmfd, HW_ANADIG_ANA_MISC0_SET,
> + BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF,
> + BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF);
> +
> + anatop_write_reg(anatopmfd, HW_ANADIG_TEMPSENSE0,
> + BM_ANADIG_TEMPSENSE0_POWER_DOWN,
> + BM_ANADIG_TEMPSENSE0_POWER_DOWN);
> +
> + therm_data->tzdev = thermal_zone_device_register(
> + "Processor", 1, therm_data, &therm_data->dev_ops, 0, 0, 0,
> + IMX_THERMAL_POLLING_FREQUENCY_MS);
> +
> + if (IS_ERR(therm_data->tzdev)) {
> + dev_err(&pdev->dev,
> + "Failed to register thermal zone device\n");
> + ret = -EINVAL;
> + goto err_unregister;
> + }
> +
> + dev_info(&pdev->dev, "imx thermal management registered\n");
> + return 0;
> +
> +err_unregister:
> + anatop_thermal_remove(pdev);
> + return ret;
> +}
> +
> +static struct of_device_id __devinitdata of_anatop_thermal_match_tbl[] = {
> + { .compatible = "fsl,anatop-thermal", },
> + { /* end */ }
> +};
> +
> +static struct platform_driver anatop_thermal = {
> + .driver = {
> + .name = "anatop_thermal",
> + .owner = THIS_MODULE,
> + .of_match_table = of_anatop_thermal_match_tbl,
> + },
> + .probe = anatop_thermal_probe,
> + .remove = anatop_thermal_remove,
> + .suspend = anatop_thermal_suspend,
> + .resume = anatop_thermal_resume,
> +};
> +
> +static int __devinit anatop_thermal_init(void)
> +{
> + return platform_driver_register(&anatop_thermal);
> +}
> +device_initcall(anatop_thermal_init);
> +
> +static void __exit anatop_thermal_exit(void)
> +{
> + platform_driver_unregister(&anatop_thermal);
> +}
> +module_exit(anatop_thermal_exit);
> +
> +MODULE_AUTHOR("Freescale Semiconductor");
> +MODULE_DESCRIPTION("i.MX anatop thermal driver");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:imx-anatop-thermal");
> --
> 1.7.10
>
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