diff options
Diffstat (limited to 'drivers/thermal/tegra/tegra30-tsensor.c')
-rw-r--r-- | drivers/thermal/tegra/tegra30-tsensor.c | 673 |
1 files changed, 673 insertions, 0 deletions
diff --git a/drivers/thermal/tegra/tegra30-tsensor.c b/drivers/thermal/tegra/tegra30-tsensor.c new file mode 100644 index 000000000..c34501287 --- /dev/null +++ b/drivers/thermal/tegra/tegra30-tsensor.c @@ -0,0 +1,673 @@ +// 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_device.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_core.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 = tz->devdata; + 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 = tz->devdata; + 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 < tzd->num_trips; i++) { + enum thermal_trip_type type; + int trip_temp; + + tzd->ops->get_trip_temp(tzd, i, &trip_temp); + tzd->ops->get_trip_type(tzd, i, &type); + + if (type == THERMAL_TRIP_HOT) + *hot_trip = trip_temp; + + if (type == THERMAL_TRIP_CRITICAL) + *crit_trip = trip_temp; + } + + /* 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); + + /* prevent potential racing with tegra_tsensor_set_trips() */ + mutex_lock(&tzd->lock); + + 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); + + mutex_unlock(&tzd->lock); + + 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; + } + + if (devm_thermal_add_hwmon_sysfs(tsc->tzd)) + dev_warn(ts->dev, "failed to add hwmon sysfs attributes\n"); + + 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; + } + + 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"); + + for (i = 0; i < ARRAY_SIZE(ts->ch); i++) { + err = tegra_tsensor_enable_hw_channel(ts, i); + if (err) + return err; + } + + 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"); |