blob: d911fa60f100457f360154f2d541431a24fa5955 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Tegra30 SoC Thermal Sensor driver
*
* Based on downstream HWMON driver from NVIDIA.
* Copyright (C) 2011 NVIDIA Corporation
*
* Author: Dmitry Osipenko <digetx@gmail.com>
* Copyright (C) 2021 GRATE-DRIVER project
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/math.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/reset.h>
#include <linux/slab.h>
#include <linux/thermal.h>
#include <linux/types.h>
#include <soc/tegra/fuse.h>
#include "../thermal_hwmon.h"
#define TSENSOR_SENSOR0_CONFIG0 0x0
#define TSENSOR_SENSOR0_CONFIG0_SENSOR_STOP BIT(0)
#define TSENSOR_SENSOR0_CONFIG0_HW_FREQ_DIV_EN BIT(1)
#define TSENSOR_SENSOR0_CONFIG0_THERMAL_RST_EN BIT(2)
#define TSENSOR_SENSOR0_CONFIG0_DVFS_EN BIT(3)
#define TSENSOR_SENSOR0_CONFIG0_INTR_OVERFLOW_EN BIT(4)
#define TSENSOR_SENSOR0_CONFIG0_INTR_HW_FREQ_DIV_EN BIT(5)
#define TSENSOR_SENSOR0_CONFIG0_INTR_THERMAL_RST_EN BIT(6)
#define TSENSOR_SENSOR0_CONFIG0_M GENMASK(23, 8)
#define TSENSOR_SENSOR0_CONFIG0_N GENMASK(31, 24)
#define TSENSOR_SENSOR0_CONFIG1 0x8
#define TSENSOR_SENSOR0_CONFIG1_TH1 GENMASK(15, 0)
#define TSENSOR_SENSOR0_CONFIG1_TH2 GENMASK(31, 16)
#define TSENSOR_SENSOR0_CONFIG2 0xc
#define TSENSOR_SENSOR0_CONFIG2_TH3 GENMASK(15, 0)
#define TSENSOR_SENSOR0_STATUS0 0x18
#define TSENSOR_SENSOR0_STATUS0_STATE GENMASK(2, 0)
#define TSENSOR_SENSOR0_STATUS0_INTR BIT(8)
#define TSENSOR_SENSOR0_STATUS0_CURRENT_VALID BIT(9)
#define TSENSOR_SENSOR0_TS_STATUS1 0x1c
#define TSENSOR_SENSOR0_TS_STATUS1_CURRENT_COUNT GENMASK(31, 16)
#define TEGRA30_FUSE_TEST_PROG_VER 0x28
#define TEGRA30_FUSE_TSENSOR_CALIB 0x98
#define TEGRA30_FUSE_TSENSOR_CALIB_LOW GENMASK(15, 0)
#define TEGRA30_FUSE_TSENSOR_CALIB_HIGH GENMASK(31, 16)
#define TEGRA30_FUSE_SPARE_BIT 0x144
struct tegra_tsensor;
struct tegra_tsensor_calibration_data {
int a, b, m, n, p, r;
};
struct tegra_tsensor_channel {
void __iomem *regs;
unsigned int id;
struct tegra_tsensor *ts;
struct thermal_zone_device *tzd;
};
struct tegra_tsensor {
void __iomem *regs;
bool swap_channels;
struct clk *clk;
struct device *dev;
struct reset_control *rst;
struct tegra_tsensor_channel ch[2];
struct tegra_tsensor_calibration_data calib;
};
static int tegra_tsensor_hw_enable(const struct tegra_tsensor *ts)
{
u32 val;
int err;
err = reset_control_assert(ts->rst);
if (err) {
dev_err(ts->dev, "failed to assert hardware reset: %d\n", err);
return err;
}
err = clk_prepare_enable(ts->clk);
if (err) {
dev_err(ts->dev, "failed to enable clock: %d\n", err);
return err;
}
fsleep(1000);
err = reset_control_deassert(ts->rst);
if (err) {
dev_err(ts->dev, "failed to deassert hardware reset: %d\n", err);
goto disable_clk;
}
/*
* Sensors are enabled after reset by default, but not gauging
* until clock counter is programmed.
*
* M: number of reference clock pulses after which every
* temperature / voltage measurement is made
*
* N: number of reference clock counts for which the counter runs
*/
val = FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_M, 12500);
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_N, 255);
/* apply the same configuration to both channels */
writel_relaxed(val, ts->regs + 0x40 + TSENSOR_SENSOR0_CONFIG0);
writel_relaxed(val, ts->regs + 0x80 + TSENSOR_SENSOR0_CONFIG0);
return 0;
disable_clk:
clk_disable_unprepare(ts->clk);
return err;
}
static int tegra_tsensor_hw_disable(const struct tegra_tsensor *ts)
{
int err;
err = reset_control_assert(ts->rst);
if (err) {
dev_err(ts->dev, "failed to assert hardware reset: %d\n", err);
return err;
}
clk_disable_unprepare(ts->clk);
return 0;
}
static void devm_tegra_tsensor_hw_disable(void *data)
{
const struct tegra_tsensor *ts = data;
tegra_tsensor_hw_disable(ts);
}
static int tegra_tsensor_get_temp(struct thermal_zone_device *tz, int *temp)
{
const struct tegra_tsensor_channel *tsc = thermal_zone_device_priv(tz);
const struct tegra_tsensor *ts = tsc->ts;
int err, c1, c2, c3, c4, counter;
u32 val;
/*
* Counter will be invalid if hardware is misprogrammed or not enough
* time passed since the time when sensor was enabled.
*/
err = readl_relaxed_poll_timeout(tsc->regs + TSENSOR_SENSOR0_STATUS0, val,
val & TSENSOR_SENSOR0_STATUS0_CURRENT_VALID,
21 * USEC_PER_MSEC,
21 * USEC_PER_MSEC * 50);
if (err) {
dev_err_once(ts->dev, "ch%u: counter invalid\n", tsc->id);
return err;
}
val = readl_relaxed(tsc->regs + TSENSOR_SENSOR0_TS_STATUS1);
counter = FIELD_GET(TSENSOR_SENSOR0_TS_STATUS1_CURRENT_COUNT, val);
/*
* This shouldn't happen with a valid counter status, nevertheless
* lets verify the value since it's in a separate (from status)
* register.
*/
if (counter == 0xffff) {
dev_err_once(ts->dev, "ch%u: counter overflow\n", tsc->id);
return -EINVAL;
}
/*
* temperature = a * counter + b
* temperature = m * (temperature ^ 2) + n * temperature + p
*/
c1 = DIV_ROUND_CLOSEST(ts->calib.a * counter + ts->calib.b, 1000000);
c1 = c1 ?: 1;
c2 = DIV_ROUND_CLOSEST(ts->calib.p, c1);
c3 = c1 * ts->calib.m;
c4 = ts->calib.n;
*temp = DIV_ROUND_CLOSEST(c1 * (c2 + c3 + c4), 1000);
return 0;
}
static int tegra_tsensor_temp_to_counter(const struct tegra_tsensor *ts, int temp)
{
int c1, c2;
c1 = DIV_ROUND_CLOSEST(ts->calib.p - temp * 1000, ts->calib.m);
c2 = -ts->calib.r - int_sqrt(ts->calib.r * ts->calib.r - c1);
return DIV_ROUND_CLOSEST(c2 * 1000000 - ts->calib.b, ts->calib.a);
}
static int tegra_tsensor_set_trips(struct thermal_zone_device *tz, int low, int high)
{
const struct tegra_tsensor_channel *tsc = thermal_zone_device_priv(tz);
const struct tegra_tsensor *ts = tsc->ts;
u32 val;
/*
* TSENSOR doesn't trigger interrupt on the "low" temperature breach,
* hence bail out if high temperature is unspecified.
*/
if (high == INT_MAX)
return 0;
val = readl_relaxed(tsc->regs + TSENSOR_SENSOR0_CONFIG1);
val &= ~TSENSOR_SENSOR0_CONFIG1_TH1;
high = tegra_tsensor_temp_to_counter(ts, high);
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG1_TH1, high);
writel_relaxed(val, tsc->regs + TSENSOR_SENSOR0_CONFIG1);
return 0;
}
static const struct thermal_zone_device_ops ops = {
.get_temp = tegra_tsensor_get_temp,
.set_trips = tegra_tsensor_set_trips,
};
static bool
tegra_tsensor_handle_channel_interrupt(const struct tegra_tsensor *ts,
unsigned int id)
{
const struct tegra_tsensor_channel *tsc = &ts->ch[id];
u32 val;
val = readl_relaxed(tsc->regs + TSENSOR_SENSOR0_STATUS0);
writel_relaxed(val, tsc->regs + TSENSOR_SENSOR0_STATUS0);
if (FIELD_GET(TSENSOR_SENSOR0_STATUS0_STATE, val) == 5)
dev_err_ratelimited(ts->dev, "ch%u: counter overflowed\n", id);
if (!FIELD_GET(TSENSOR_SENSOR0_STATUS0_INTR, val))
return false;
thermal_zone_device_update(tsc->tzd, THERMAL_EVENT_UNSPECIFIED);
return true;
}
static irqreturn_t tegra_tsensor_isr(int irq, void *data)
{
const struct tegra_tsensor *ts = data;
bool handled = false;
unsigned int i;
for (i = 0; i < ARRAY_SIZE(ts->ch); i++)
handled |= tegra_tsensor_handle_channel_interrupt(ts, i);
return handled ? IRQ_HANDLED : IRQ_NONE;
}
static int tegra_tsensor_disable_hw_channel(const struct tegra_tsensor *ts,
unsigned int id)
{
const struct tegra_tsensor_channel *tsc = &ts->ch[id];
struct thermal_zone_device *tzd = tsc->tzd;
u32 val;
int err;
if (!tzd)
goto stop_channel;
err = thermal_zone_device_disable(tzd);
if (err) {
dev_err(ts->dev, "ch%u: failed to disable zone: %d\n", id, err);
return err;
}
stop_channel:
/* stop channel gracefully */
val = readl_relaxed(tsc->regs + TSENSOR_SENSOR0_CONFIG0);
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_SENSOR_STOP, 1);
writel_relaxed(val, tsc->regs + TSENSOR_SENSOR0_CONFIG0);
return 0;
}
static void tegra_tsensor_get_hw_channel_trips(struct thermal_zone_device *tzd,
int *hot_trip, int *crit_trip)
{
unsigned int i;
/*
* 90C is the maximal critical temperature of all Tegra30 SoC variants,
* use it for the default trip if unspecified in a device-tree.
*/
*hot_trip = 85000;
*crit_trip = 90000;
for (i = 0; i < thermal_zone_get_num_trips(tzd); i++) {
struct thermal_trip trip;
thermal_zone_get_trip(tzd, i, &trip);
if (trip.type == THERMAL_TRIP_HOT)
*hot_trip = trip.temperature;
if (trip.type == THERMAL_TRIP_CRITICAL)
*crit_trip = trip.temperature;
}
/* clamp hardware trips to the calibration limits */
*hot_trip = clamp(*hot_trip, 25000, 90000);
/*
* Kernel will perform a normal system shut down if it will
* see that critical temperature is breached, hence set the
* hardware limit by 5C higher in order to allow system to
* shut down gracefully before sending signal to the Power
* Management controller.
*/
*crit_trip = clamp(*crit_trip + 5000, 25000, 90000);
}
static int tegra_tsensor_enable_hw_channel(const struct tegra_tsensor *ts,
unsigned int id)
{
const struct tegra_tsensor_channel *tsc = &ts->ch[id];
struct thermal_zone_device *tzd = tsc->tzd;
int err, hot_trip = 0, crit_trip = 0;
u32 val;
if (!tzd) {
val = readl_relaxed(tsc->regs + TSENSOR_SENSOR0_CONFIG0);
val &= ~TSENSOR_SENSOR0_CONFIG0_SENSOR_STOP;
writel_relaxed(val, tsc->regs + TSENSOR_SENSOR0_CONFIG0);
return 0;
}
tegra_tsensor_get_hw_channel_trips(tzd, &hot_trip, &crit_trip);
dev_info_once(ts->dev, "ch%u: PMC emergency shutdown trip set to %dC\n",
id, DIV_ROUND_CLOSEST(crit_trip, 1000));
hot_trip = tegra_tsensor_temp_to_counter(ts, hot_trip);
crit_trip = tegra_tsensor_temp_to_counter(ts, crit_trip);
/* program LEVEL2 counter threshold */
val = readl_relaxed(tsc->regs + TSENSOR_SENSOR0_CONFIG1);
val &= ~TSENSOR_SENSOR0_CONFIG1_TH2;
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG1_TH2, hot_trip);
writel_relaxed(val, tsc->regs + TSENSOR_SENSOR0_CONFIG1);
/* program LEVEL3 counter threshold */
val = readl_relaxed(tsc->regs + TSENSOR_SENSOR0_CONFIG2);
val &= ~TSENSOR_SENSOR0_CONFIG2_TH3;
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG2_TH3, crit_trip);
writel_relaxed(val, tsc->regs + TSENSOR_SENSOR0_CONFIG2);
/*
* Enable sensor, emergency shutdown, interrupts for level 1/2/3
* breaches and counter overflow condition.
*
* Disable DIV2 throttle for now since we need to figure out how
* to integrate it properly with the thermal framework.
*
* Thermal levels supported by hardware:
*
* Level 0 = cold
* Level 1 = passive cooling (cpufreq DVFS)
* Level 2 = passive cooling assisted by hardware (DIV2)
* Level 3 = emergency shutdown assisted by hardware (PMC)
*/
val = readl_relaxed(tsc->regs + TSENSOR_SENSOR0_CONFIG0);
val &= ~TSENSOR_SENSOR0_CONFIG0_SENSOR_STOP;
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_DVFS_EN, 1);
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_HW_FREQ_DIV_EN, 0);
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_THERMAL_RST_EN, 1);
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_INTR_OVERFLOW_EN, 1);
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_INTR_HW_FREQ_DIV_EN, 1);
val |= FIELD_PREP(TSENSOR_SENSOR0_CONFIG0_INTR_THERMAL_RST_EN, 1);
writel_relaxed(val, tsc->regs + TSENSOR_SENSOR0_CONFIG0);
err = thermal_zone_device_enable(tzd);
if (err) {
dev_err(ts->dev, "ch%u: failed to enable zone: %d\n", id, err);
return err;
}
return 0;
}
static bool tegra_tsensor_fuse_read_spare(unsigned int spare)
{
u32 val = 0;
tegra_fuse_readl(TEGRA30_FUSE_SPARE_BIT + spare * 4, &val);
return !!val;
}
static int tegra_tsensor_nvmem_setup(struct tegra_tsensor *ts)
{
u32 i, ate_ver = 0, cal = 0, t1_25C = 0, t2_90C = 0;
int err, c1_25C, c2_90C;
err = tegra_fuse_readl(TEGRA30_FUSE_TEST_PROG_VER, &ate_ver);
if (err) {
dev_err_probe(ts->dev, err, "failed to get ATE version\n");
return err;
}
if (ate_ver < 8) {
dev_info(ts->dev, "unsupported ATE version: %u\n", ate_ver);
return -ENODEV;
}
/*
* We have two TSENSOR channels in a two different spots on SoC.
* Second channel provides more accurate data on older SoC versions,
* use it as a primary channel.
*/
if (ate_ver <= 21) {
dev_info_once(ts->dev,
"older ATE version detected, channels remapped\n");
ts->swap_channels = true;
}
err = tegra_fuse_readl(TEGRA30_FUSE_TSENSOR_CALIB, &cal);
if (err) {
dev_err(ts->dev, "failed to get calibration data: %d\n", err);
return err;
}
/* get calibrated counter values for 25C/90C thresholds */
c1_25C = FIELD_GET(TEGRA30_FUSE_TSENSOR_CALIB_LOW, cal);
c2_90C = FIELD_GET(TEGRA30_FUSE_TSENSOR_CALIB_HIGH, cal);
/* and calibrated temperatures corresponding to the counter values */
for (i = 0; i < 7; i++) {
t1_25C |= tegra_tsensor_fuse_read_spare(14 + i) << i;
t1_25C |= tegra_tsensor_fuse_read_spare(21 + i) << i;
t2_90C |= tegra_tsensor_fuse_read_spare(0 + i) << i;
t2_90C |= tegra_tsensor_fuse_read_spare(7 + i) << i;
}
if (c2_90C - c1_25C <= t2_90C - t1_25C) {
dev_err(ts->dev, "invalid calibration data: %d %d %u %u\n",
c2_90C, c1_25C, t2_90C, t1_25C);
return -EINVAL;
}
/* all calibration coefficients are premultiplied by 1000000 */
ts->calib.a = DIV_ROUND_CLOSEST((t2_90C - t1_25C) * 1000000,
(c2_90C - c1_25C));
ts->calib.b = t1_25C * 1000000 - ts->calib.a * c1_25C;
if (tegra_sku_info.revision == TEGRA_REVISION_A01) {
ts->calib.m = -2775;
ts->calib.n = 1338811;
ts->calib.p = -7300000;
} else {
ts->calib.m = -3512;
ts->calib.n = 1528943;
ts->calib.p = -11100000;
}
/* except the coefficient of a reduced quadratic equation */
ts->calib.r = DIV_ROUND_CLOSEST(ts->calib.n, ts->calib.m * 2);
dev_info_once(ts->dev,
"calibration: %d %d %u %u ATE ver: %u SoC rev: %u\n",
c2_90C, c1_25C, t2_90C, t1_25C, ate_ver,
tegra_sku_info.revision);
return 0;
}
static int tegra_tsensor_register_channel(struct tegra_tsensor *ts,
unsigned int id)
{
struct tegra_tsensor_channel *tsc = &ts->ch[id];
unsigned int hw_id = ts->swap_channels ? !id : id;
tsc->ts = ts;
tsc->id = id;
tsc->regs = ts->regs + 0x40 * (hw_id + 1);
tsc->tzd = devm_thermal_of_zone_register(ts->dev, id, tsc, &ops);
if (IS_ERR(tsc->tzd)) {
if (PTR_ERR(tsc->tzd) != -ENODEV)
return dev_err_probe(ts->dev, PTR_ERR(tsc->tzd),
"failed to register thermal zone\n");
/*
* It's okay if sensor isn't assigned to any thermal zone
* in a device-tree.
*/
tsc->tzd = NULL;
return 0;
}
devm_thermal_add_hwmon_sysfs(ts->dev, tsc->tzd);
return 0;
}
static int tegra_tsensor_probe(struct platform_device *pdev)
{
struct tegra_tsensor *ts;
unsigned int i;
int err, irq;
ts = devm_kzalloc(&pdev->dev, sizeof(*ts), GFP_KERNEL);
if (!ts)
return -ENOMEM;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
ts->dev = &pdev->dev;
platform_set_drvdata(pdev, ts);
ts->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(ts->regs))
return PTR_ERR(ts->regs);
ts->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(ts->clk))
return dev_err_probe(&pdev->dev, PTR_ERR(ts->clk),
"failed to get clock\n");
ts->rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
if (IS_ERR(ts->rst))
return dev_err_probe(&pdev->dev, PTR_ERR(ts->rst),
"failed to get reset control\n");
err = tegra_tsensor_nvmem_setup(ts);
if (err)
return err;
err = tegra_tsensor_hw_enable(ts);
if (err)
return err;
err = devm_add_action_or_reset(&pdev->dev,
devm_tegra_tsensor_hw_disable,
ts);
if (err)
return err;
for (i = 0; i < ARRAY_SIZE(ts->ch); i++) {
err = tegra_tsensor_register_channel(ts, i);
if (err)
return err;
}
/*
* Enable the channels before setting the interrupt so
* set_trips() can not be called while we are setting up the
* register TSENSOR_SENSOR0_CONFIG1. With this we close a
* potential race window where we are setting up the TH2 and
* the temperature hits TH1 resulting to an update of the
* TSENSOR_SENSOR0_CONFIG1 register in the ISR.
*/
for (i = 0; i < ARRAY_SIZE(ts->ch); i++) {
err = tegra_tsensor_enable_hw_channel(ts, i);
if (err)
return err;
}
err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
tegra_tsensor_isr, IRQF_ONESHOT,
"tegra_tsensor", ts);
if (err)
return dev_err_probe(&pdev->dev, err,
"failed to request interrupt\n");
return 0;
}
static int __maybe_unused tegra_tsensor_suspend(struct device *dev)
{
struct tegra_tsensor *ts = dev_get_drvdata(dev);
unsigned int i;
int err;
for (i = 0; i < ARRAY_SIZE(ts->ch); i++) {
err = tegra_tsensor_disable_hw_channel(ts, i);
if (err)
goto enable_channel;
}
err = tegra_tsensor_hw_disable(ts);
if (err)
goto enable_channel;
return 0;
enable_channel:
while (i--)
tegra_tsensor_enable_hw_channel(ts, i);
return err;
}
static int __maybe_unused tegra_tsensor_resume(struct device *dev)
{
struct tegra_tsensor *ts = dev_get_drvdata(dev);
unsigned int i;
int err;
err = tegra_tsensor_hw_enable(ts);
if (err)
return err;
for (i = 0; i < ARRAY_SIZE(ts->ch); i++) {
err = tegra_tsensor_enable_hw_channel(ts, i);
if (err)
return err;
}
return 0;
}
static const struct dev_pm_ops tegra_tsensor_pm_ops = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_tsensor_suspend,
tegra_tsensor_resume)
};
static const struct of_device_id tegra_tsensor_of_match[] = {
{ .compatible = "nvidia,tegra30-tsensor", },
{},
};
MODULE_DEVICE_TABLE(of, tegra_tsensor_of_match);
static struct platform_driver tegra_tsensor_driver = {
.probe = tegra_tsensor_probe,
.driver = {
.name = "tegra30-tsensor",
.of_match_table = tegra_tsensor_of_match,
.pm = &tegra_tsensor_pm_ops,
},
};
module_platform_driver(tegra_tsensor_driver);
MODULE_DESCRIPTION("NVIDIA Tegra30 Thermal Sensor driver");
MODULE_AUTHOR("Dmitry Osipenko <digetx@gmail.com>");
MODULE_LICENSE("GPL");