- 根目录:
- drivers
- thermal
- imx_thermal.c
/*
* Copyright 2013 Freescale Semiconductor, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/clk.h>
#include <linux/cpu_cooling.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/thermal.h>
#include <linux/types.h>
#define REG_SET 0x4
#define REG_CLR 0x8
#define REG_TOG 0xc
#define MISC0 0x0150
#define MISC0_REFTOP_SELBIASOFF (1 << 3)
#define MISC1 0x0160
#define MISC1_IRQ_TEMPHIGH (1 << 29)
/* Below LOW and PANIC bits are only for TEMPMON_IMX6SX */
#define MISC1_IRQ_TEMPLOW (1 << 28)
#define MISC1_IRQ_TEMPPANIC (1 << 27)
#define TEMPSENSE0 0x0180
#define TEMPSENSE0_ALARM_VALUE_SHIFT 20
#define TEMPSENSE0_ALARM_VALUE_MASK (0xfff << TEMPSENSE0_ALARM_VALUE_SHIFT)
#define TEMPSENSE0_TEMP_CNT_SHIFT 8
#define TEMPSENSE0_TEMP_CNT_MASK (0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
#define TEMPSENSE0_FINISHED (1 << 2)
#define TEMPSENSE0_MEASURE_TEMP (1 << 1)
#define TEMPSENSE0_POWER_DOWN (1 << 0)
#define TEMPSENSE1 0x0190
#define TEMPSENSE1_MEASURE_FREQ 0xffff
/* Below TEMPSENSE2 is only for TEMPMON_IMX6SX */
#define TEMPSENSE2 0x0290
#define TEMPSENSE2_LOW_VALUE_SHIFT 0
#define TEMPSENSE2_LOW_VALUE_MASK 0xfff
#define TEMPSENSE2_PANIC_VALUE_SHIFT 16
#define TEMPSENSE2_PANIC_VALUE_MASK 0xfff0000
#define OCOTP_MEM0 0x0480
#define OCOTP_ANA1 0x04e0
/* The driver supports 1 passive trip point and 1 critical trip point */
enum imx_thermal_trip {
IMX_TRIP_PASSIVE,
IMX_TRIP_CRITICAL,
IMX_TRIP_NUM,
};
#define IMX_POLLING_DELAY 2000 /* millisecond */
#define IMX_PASSIVE_DELAY 1000
#define FACTOR0 10000000
#define FACTOR1 15976
#define FACTOR2 4297157
#define TEMPMON_IMX6Q 1
#define TEMPMON_IMX6SX 2
struct thermal_soc_data {
u32 version;
};
static struct thermal_soc_data thermal_imx6q_data = {
.version = TEMPMON_IMX6Q,
};
static struct thermal_soc_data thermal_imx6sx_data = {
.version = TEMPMON_IMX6SX,
};
struct imx_thermal_data {
struct thermal_zone_device *tz;
struct thermal_cooling_device *cdev;
enum thermal_device_mode mode;
struct regmap *tempmon;
u32 c1, c2; /* See formula in imx_get_sensor_data() */
int temp_passive;
int temp_critical;
int temp_max;
int alarm_temp;
int last_temp;
bool irq_enabled;
int irq;
struct clk *thermal_clk;
const struct thermal_soc_data *socdata;
const char *temp_grade;
};
static void imx_set_panic_temp(struct imx_thermal_data *data,
int panic_temp)
{
struct regmap *map = data->tempmon;
int critical_value;
critical_value = (data->c2 - panic_temp) / data->c1;
regmap_write(map, TEMPSENSE2 + REG_CLR, TEMPSENSE2_PANIC_VALUE_MASK);
regmap_write(map, TEMPSENSE2 + REG_SET, critical_value <<
TEMPSENSE2_PANIC_VALUE_SHIFT);
}
static void imx_set_alarm_temp(struct imx_thermal_data *data,
int alarm_temp)
{
struct regmap *map = data->tempmon;
int alarm_value;
data->alarm_temp = alarm_temp;
alarm_value = (data->c2 - alarm_temp) / data->c1;
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_ALARM_VALUE_MASK);
regmap_write(map, TEMPSENSE0 + REG_SET, alarm_value <<
TEMPSENSE0_ALARM_VALUE_SHIFT);
}
static int imx_get_temp(struct thermal_zone_device *tz, int *temp)
{
struct imx_thermal_data *data = tz->devdata;
struct regmap *map = data->tempmon;
unsigned int n_meas;
bool wait;
u32 val;
if (data->mode == THERMAL_DEVICE_ENABLED) {
/* Check if a measurement is currently in progress */
regmap_read(map, TEMPSENSE0, &val);
wait = !(val & TEMPSENSE0_FINISHED);
} else {
/*
* 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.
*/
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
wait = true;
}
/*
* According to the temp sensor designers, it may require up to ~17us
* to complete a measurement.
*/
if (wait)
usleep_range(20, 50);
regmap_read(map, TEMPSENSE0, &val);
if (data->mode != THERMAL_DEVICE_ENABLED) {
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
}
if ((val & TEMPSENSE0_FINISHED) == 0) {
dev_dbg(&tz->device, "temp measurement never finished\n");
return -EAGAIN;
}
n_meas = (val & TEMPSENSE0_TEMP_CNT_MASK) >> TEMPSENSE0_TEMP_CNT_SHIFT;
/* See imx_get_sensor_data() for formula derivation */
*temp = data->c2 - n_meas * data->c1;
/* Update alarm value to next higher trip point for TEMPMON_IMX6Q */
if (data->socdata->version == TEMPMON_IMX6Q) {
if (data->alarm_temp == data->temp_passive &&
*temp >= data->temp_passive)
imx_set_alarm_temp(data, data->temp_critical);
if (data->alarm_temp == data->temp_critical &&
*temp < data->temp_passive) {
imx_set_alarm_temp(data, data->temp_passive);
dev_dbg(&tz->device, "thermal alarm off: T < %d\n",
data->alarm_temp / 1000);
}
}
if (*temp != data->last_temp) {
dev_dbg(&tz->device, "millicelsius: %d\n", *temp);
data->last_temp = *temp;
}
/* Reenable alarm IRQ if temperature below alarm temperature */
if (!data->irq_enabled && *temp < data->alarm_temp) {
data->irq_enabled = true;
enable_irq(data->irq);
}
return 0;
}
static int imx_get_mode(struct thermal_zone_device *tz,
enum thermal_device_mode *mode)
{
struct imx_thermal_data *data = tz->devdata;
*mode = data->mode;
return 0;
}
static int imx_set_mode(struct thermal_zone_device *tz,
enum thermal_device_mode mode)
{
struct imx_thermal_data *data = tz->devdata;
struct regmap *map = data->tempmon;
if (mode == THERMAL_DEVICE_ENABLED) {
tz->polling_delay = IMX_POLLING_DELAY;
tz->passive_delay = IMX_PASSIVE_DELAY;
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
if (!data->irq_enabled) {
data->irq_enabled = true;
enable_irq(data->irq);
}
} else {
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
tz->polling_delay = 0;
tz->passive_delay = 0;
if (data->irq_enabled) {
disable_irq(data->irq);
data->irq_enabled = false;
}
}
data->mode = mode;
thermal_zone_device_update(tz);
return 0;
}
static int imx_get_trip_type(struct thermal_zone_device *tz, int trip,
enum thermal_trip_type *type)
{
*type = (trip == IMX_TRIP_PASSIVE) ? THERMAL_TRIP_PASSIVE :
THERMAL_TRIP_CRITICAL;
return 0;
}
static int imx_get_crit_temp(struct thermal_zone_device *tz, int *temp)
{
struct imx_thermal_data *data = tz->devdata;
*temp = data->temp_critical;
return 0;
}
static int imx_get_trip_temp(struct thermal_zone_device *tz, int trip,
int *temp)
{
struct imx_thermal_data *data = tz->devdata;
*temp = (trip == IMX_TRIP_PASSIVE) ? data->temp_passive :
data->temp_critical;
return 0;
}
static int imx_set_trip_temp(struct thermal_zone_device *tz, int trip,
int temp)
{
struct imx_thermal_data *data = tz->devdata;
/* do not allow changing critical threshold */
if (trip == IMX_TRIP_CRITICAL)
return -EPERM;
/* do not allow passive to be set higher than critical */
if (temp < 0 || temp > data->temp_critical)
return -EINVAL;
data->temp_passive = temp;
imx_set_alarm_temp(data, temp);
return 0;
}
static int imx_bind(struct thermal_zone_device *tz,
struct thermal_cooling_device *cdev)
{
int ret;
ret = thermal_zone_bind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev,
THERMAL_NO_LIMIT,
THERMAL_NO_LIMIT,
THERMAL_WEIGHT_DEFAULT);
if (ret) {
dev_err(&tz->device,
"binding zone %s with cdev %s failed:%d\n",
tz->type, cdev->type, ret);
return ret;
}
return 0;
}
static int imx_unbind(struct thermal_zone_device *tz,
struct thermal_cooling_device *cdev)
{
int ret;
ret = thermal_zone_unbind_cooling_device(tz, IMX_TRIP_PASSIVE, cdev);
if (ret) {
dev_err(&tz->device,
"unbinding zone %s with cdev %s failed:%d\n",
tz->type, cdev->type, ret);
return ret;
}
return 0;
}
static struct thermal_zone_device_ops imx_tz_ops = {
.bind = imx_bind,
.unbind = imx_unbind,
.get_temp = imx_get_temp,
.get_mode = imx_get_mode,
.set_mode = imx_set_mode,
.get_trip_type = imx_get_trip_type,
.get_trip_temp = imx_get_trip_temp,
.get_crit_temp = imx_get_crit_temp,
.set_trip_temp = imx_set_trip_temp,
};
static int imx_get_sensor_data(struct platform_device *pdev)
{
struct imx_thermal_data *data = platform_get_drvdata(pdev);
struct regmap *map;
int t1, n1;
int ret;
u32 val;
u64 temp64;
map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
"fsl,tempmon-data");
if (IS_ERR(map)) {
ret = PTR_ERR(map);
dev_err(&pdev->dev, "failed to get sensor regmap: %d\n", ret);
return ret;
}
ret = regmap_read(map, OCOTP_ANA1, &val);
if (ret) {
dev_err(&pdev->dev, "failed to read sensor data: %d\n", ret);
return ret;
}
if (val == 0 || val == ~0) {
dev_err(&pdev->dev, "invalid sensor calibration data\n");
return -EINVAL;
}
/*
* Sensor data layout:
* [31:20] - sensor value @ 25C
* Use universal formula now and only need sensor value @ 25C
* slope = 0.4297157 - (0.0015976 * 25C fuse)
*/
n1 = val >> 20;
t1 = 25; /* t1 always 25C */
/*
* Derived from linear interpolation:
* slope = 0.4297157 - (0.0015976 * 25C fuse)
* slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
* (Nmeas - n1) / (Tmeas - t1) = slope
* 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...
* Tmeas = (Nmeas - n1) / slope + t1
* milli_Tmeas = 1000 * (Nmeas - n1) / slope + 1000 * t1
* milli_Tmeas = -1000 * (n1 - Nmeas) / slope + 1000 * t1
* Let constant c1 = (-1000 / slope)
* milli_Tmeas = (n1 - Nmeas) * c1 + 1000 * t1
* Let constant c2 = n1 *c1 + 1000 * t1
* milli_Tmeas = c2 - Nmeas * c1
*/
temp64 = FACTOR0;
temp64 *= 1000;
do_div(temp64, FACTOR1 * n1 - FACTOR2);
data->c1 = temp64;
data->c2 = n1 * data->c1 + 1000 * t1;
/* use OTP for thermal grade */
ret = regmap_read(map, OCOTP_MEM0, &val);
if (ret) {
dev_err(&pdev->dev, "failed to read temp grade: %d\n", ret);
return ret;
}
/* The maximum die temp is specified by the Temperature Grade */
switch ((val >> 6) & 0x3) {
case 0: /* Commercial (0 to 95C) */
data->temp_grade = "Commercial";
data->temp_max = 95000;
break;
case 1: /* Extended Commercial (-20 to 105C) */
data->temp_grade = "Extended Commercial";
data->temp_max = 105000;
break;
case 2: /* Industrial (-40 to 105C) */
data->temp_grade = "Industrial";
data->temp_max = 105000;
break;
case 3: /* Automotive (-40 to 125C) */
data->temp_grade = "Automotive";
data->temp_max = 125000;
break;
}
/*
* Set the critical trip point at 5C under max
* Set the passive trip point at 10C under max (can change via sysfs)
*/
data->temp_critical = data->temp_max - (1000 * 5);
data->temp_passive = data->temp_max - (1000 * 10);
return 0;
}
static irqreturn_t imx_thermal_alarm_irq(int irq, void *dev)
{
struct imx_thermal_data *data = dev;
disable_irq_nosync(irq);
data->irq_enabled = false;
return IRQ_WAKE_THREAD;
}
static irqreturn_t imx_thermal_alarm_irq_thread(int irq, void *dev)
{
struct imx_thermal_data *data = dev;
dev_dbg(&data->tz->device, "THERMAL ALARM: T > %d\n",
data->alarm_temp / 1000);
thermal_zone_device_update(data->tz);
return IRQ_HANDLED;
}
static const struct of_device_id of_imx_thermal_match[] = {
{ .compatible = "fsl,imx6q-tempmon", .data = &thermal_imx6q_data, },
{ .compatible = "fsl,imx6sx-tempmon", .data = &thermal_imx6sx_data, },
{ /* end */ }
};
MODULE_DEVICE_TABLE(of, of_imx_thermal_match);
static int imx_thermal_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id =
of_match_device(of_imx_thermal_match, &pdev->dev);
struct imx_thermal_data *data;
struct regmap *map;
int measure_freq;
int ret;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "fsl,tempmon");
if (IS_ERR(map)) {
ret = PTR_ERR(map);
dev_err(&pdev->dev, "failed to get tempmon regmap: %d\n", ret);
return ret;
}
data->tempmon = map;
data->socdata = of_id->data;
/* make sure the IRQ flag is clear before enabling irq on i.MX6SX */
if (data->socdata->version == TEMPMON_IMX6SX) {
regmap_write(map, MISC1 + REG_CLR, MISC1_IRQ_TEMPHIGH |
MISC1_IRQ_TEMPLOW | MISC1_IRQ_TEMPPANIC);
/*
* reset value of LOW ALARM is incorrect, set it to lowest
* value to avoid false trigger of low alarm.
*/
regmap_write(map, TEMPSENSE2 + REG_SET,
TEMPSENSE2_LOW_VALUE_MASK);
}
data->irq = platform_get_irq(pdev, 0);
if (data->irq < 0)
return data->irq;
platform_set_drvdata(pdev, data);
ret = imx_get_sensor_data(pdev);
if (ret) {
dev_err(&pdev->dev, "failed to get sensor data\n");
return ret;
}
/* Make sure sensor is in known good state for measurements */
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
regmap_write(map, MISC0 + REG_SET, MISC0_REFTOP_SELBIASOFF);
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
data->cdev = cpufreq_cooling_register(cpu_present_mask);
if (IS_ERR(data->cdev)) {
ret = PTR_ERR(data->cdev);
if (ret != -EPROBE_DEFER)
dev_err(&pdev->dev,
"failed to register cpufreq cooling device: %d\n",
ret);
return ret;
}
data->thermal_clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(data->thermal_clk)) {
ret = PTR_ERR(data->thermal_clk);
if (ret != -EPROBE_DEFER)
dev_err(&pdev->dev,
"failed to get thermal clk: %d\n", ret);
cpufreq_cooling_unregister(data->cdev);
return ret;
}
/*
* Thermal sensor needs clk on to get correct value, normally
* we should enable its clk before taking measurement and disable
* clk after measurement is done, but if alarm function is enabled,
* hardware will auto measure the temperature periodically, so we
* need to keep the clk always on for alarm function.
*/
ret = clk_prepare_enable(data->thermal_clk);
if (ret) {
dev_err(&pdev->dev, "failed to enable thermal clk: %d\n", ret);
cpufreq_cooling_unregister(data->cdev);
return ret;
}
data->tz = thermal_zone_device_register("imx_thermal_zone",
IMX_TRIP_NUM,
BIT(IMX_TRIP_PASSIVE), data,
&imx_tz_ops, NULL,
IMX_PASSIVE_DELAY,
IMX_POLLING_DELAY);
if (IS_ERR(data->tz)) {
ret = PTR_ERR(data->tz);
dev_err(&pdev->dev,
"failed to register thermal zone device %d\n", ret);
clk_disable_unprepare(data->thermal_clk);
cpufreq_cooling_unregister(data->cdev);
return ret;
}
dev_info(&pdev->dev, "%s CPU temperature grade - max:%dC"
" critical:%dC passive:%dC\n", data->temp_grade,
data->temp_max / 1000, data->temp_critical / 1000,
data->temp_passive / 1000);
/* Enable measurements at ~ 10 Hz */
regmap_write(map, TEMPSENSE1 + REG_CLR, TEMPSENSE1_MEASURE_FREQ);
measure_freq = DIV_ROUND_UP(32768, 10); /* 10 Hz */
regmap_write(map, TEMPSENSE1 + REG_SET, measure_freq);
imx_set_alarm_temp(data, data->temp_passive);
if (data->socdata->version == TEMPMON_IMX6SX)
imx_set_panic_temp(data, data->temp_critical);
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
ret = devm_request_threaded_irq(&pdev->dev, data->irq,
imx_thermal_alarm_irq, imx_thermal_alarm_irq_thread,
0, "imx_thermal", data);
if (ret < 0) {
dev_err(&pdev->dev, "failed to request alarm irq: %d\n", ret);
clk_disable_unprepare(data->thermal_clk);
thermal_zone_device_unregister(data->tz);
cpufreq_cooling_unregister(data->cdev);
return ret;
}
data->irq_enabled = true;
data->mode = THERMAL_DEVICE_ENABLED;
return 0;
}
static int imx_thermal_remove(struct platform_device *pdev)
{
struct imx_thermal_data *data = platform_get_drvdata(pdev);
struct regmap *map = data->tempmon;
/* Disable measurements */
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
if (!IS_ERR(data->thermal_clk))
clk_disable_unprepare(data->thermal_clk);
thermal_zone_device_unregister(data->tz);
cpufreq_cooling_unregister(data->cdev);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int imx_thermal_suspend(struct device *dev)
{
struct imx_thermal_data *data = dev_get_drvdata(dev);
struct regmap *map = data->tempmon;
/*
* Need to disable thermal sensor, otherwise, when thermal core
* try to get temperature before thermal sensor resume, a wrong
* temperature will be read as the thermal sensor is powered
* down.
*/
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_MEASURE_TEMP);
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_POWER_DOWN);
data->mode = THERMAL_DEVICE_DISABLED;
clk_disable_unprepare(data->thermal_clk);
return 0;
}
static int imx_thermal_resume(struct device *dev)
{
struct imx_thermal_data *data = dev_get_drvdata(dev);
struct regmap *map = data->tempmon;
clk_prepare_enable(data->thermal_clk);
/* Enabled thermal sensor after resume */
regmap_write(map, TEMPSENSE0 + REG_CLR, TEMPSENSE0_POWER_DOWN);
regmap_write(map, TEMPSENSE0 + REG_SET, TEMPSENSE0_MEASURE_TEMP);
data->mode = THERMAL_DEVICE_ENABLED;
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(imx_thermal_pm_ops,
imx_thermal_suspend, imx_thermal_resume);
static struct platform_driver imx_thermal = {
.driver = {
.name = "imx_thermal",
.pm = &imx_thermal_pm_ops,
.of_match_table = of_imx_thermal_match,
},
.probe = imx_thermal_probe,
.remove = imx_thermal_remove,
};
module_platform_driver(imx_thermal);
MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("Thermal driver for Freescale i.MX SoCs");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:imx-thermal");