Re: [PATCH 2/3] thermal: Add Mediatek thermal controller support

Andy Shevchenko
2015-11-09T14:39:42Z

On Mon, Nov 9, 2015 at 12:13 PM, Sascha Hauer <s.hauer@pengutronix.de> wrote:
> This adds support for the Mediatek thermal controller found on MT8173
> and likely other SoCs.
> The controller is a bit special. It does not have its own ADC, instead
> it controls the on-SoC AUXADC via AHB bus accesses. For this reason
> we need the physical address of the AUXADC. Also it controls a mux
> using AHB bus accesses, so we need the APMIXEDSYS physical address aswell.

Few style nitpicks.

> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/io.h>
> +#include <linux/thermal.h>
> +#include <linux/reset.h>
> +#include <linux/types.h>
> +#include <linux/nvmem-consumer.h>
> +
> +/* AUXADC Registers */
> +#define AUXADC_CON0_V 0x000
> +#define AUXADC_CON1_V 0x004
> +#define AUXADC_CON1_SET_V 0x008
> +#define AUXADC_CON1_CLR_V 0x00c
> +#define AUXADC_CON2_V 0x010
> +#define AUXADC_DATA(channel) (0x14 + (channel) * 4)
> +#define AUXADC_MISC_V 0x094
> +
> +#define AUXADC_CON1_CHANNEL(x) BIT(x)
> +
> +#define APMIXED_SYS_TS_CON1 0x604
> +
> +/* Thermal Controller Registers */
> +#define TEMP_MONCTL0 0x000
> +#define TEMP_MONCTL1 0x004
> +#define TEMP_MONCTL2 0x008
> +#define TEMP_MONIDET0 0x014
> +#define TEMP_MONIDET1 0x018
> +#define TEMP_MSRCTL0 0x038
> +#define TEMP_AHBPOLL 0x040
> +#define TEMP_AHBTO 0x044
> +#define TEMP_ADCPNP0 0x048
> +#define TEMP_ADCPNP1 0x04c
> +#define TEMP_ADCPNP2 0x050
> +#define TEMP_ADCPNP3 0x0b4
> +
> +#define TEMP_ADCMUX 0x054
> +#define TEMP_ADCEN 0x060
> +#define TEMP_PNPMUXADDR 0x064
> +#define TEMP_ADCMUXADDR 0x068
> +#define TEMP_ADCENADDR 0x074
> +#define TEMP_ADCVALIDADDR 0x078
> +#define TEMP_ADCVOLTADDR 0x07c
> +#define TEMP_RDCTRL 0x080
> +#define TEMP_ADCVALIDMASK 0x084
> +#define TEMP_ADCVOLTAGESHIFT 0x088
> +#define TEMP_ADCWRITECTRL 0x08c
> +#define TEMP_MSR0 0x090
> +#define TEMP_MSR1 0x094
> +#define TEMP_MSR2 0x098
> +#define TEMP_MSR3 0x0B8
> +
> +#define TEMP_SPARE0 0x0f0
> +
> +#define PTPCORESEL 0x400
> +
> +#define TEMP_MONCTL1_PERIOD_UNIT(x) ((x) & 0x3ff)
> +
> +#define TEMP_MONCTL2_FILTER_INTERVAL(x) (((x) & 0x3ff)) << 16
> +#define TEMP_MONCTL2_SENSOR_INTERVAL(x) ((x) & 0x3ff)
> +
> +#define TEMP_AHBPOLL_ADC_POLL_INTERVAL(x) (x)
> +
> +#define TEMP_ADCWRITECTRL_ADC_PNP_WRITE BIT(0)
> +#define TEMP_ADCWRITECTRL_ADC_MUX_WRITE BIT(1)
> +
> +#define TEMP_ADCVALIDMASK_VALID_HIGH BIT(5)
> +#define TEMP_ADCVALIDMASK_VALID_POS(bit) (bit)
> +
> +#define MT8173_TS1 0
> +#define MT8173_TS2 1
> +#define MT8173_TS3 2
> +#define MT8173_TS4 3
> +#define MT8173_TSABB 4
> +
> +/* AUXADC channel 11 is used for the temperature sensors */
> +#define MT8173_TEMP_AUXADC_CHANNEL 11
> +
> +/* The total number of temperature sensors in the MT8173 */
> +#define MT8173_NUM_SENSORS 5
> +
> +/* The number of banks in the MT8173 */
> +#define MT8173_NUM_ZONES 4
> +
> +/* The number of sensing points per bank */
> +#define MT8173_NUM_SENSORS_PER_ZONE 4
> +
> +/* Layout of the fuses providing the calibration data */
> +#define MT8173_CALIB_BUF0_VALID (1 << 0)
> +#define MT8173_CALIB_BUF1_ADC_GE(x) (((x) >> 22 ) & 0x3ff)
> +#define MT8173_CALIB_BUF0_VTS_TS1(x) (((x) >> 17 ) & 0x1ff)
> +#define MT8173_CALIB_BUF0_VTS_TS2(x) (((x) >> 8 ) & 0x1ff)
> +#define MT8173_CALIB_BUF1_VTS_TS3(x) (((x) >> 0 ) & 0x1ff)
> +#define MT8173_CALIB_BUF2_VTS_TS4(x) (((x) >> 23 ) & 0x1ff)
> +#define MT8173_CALIB_BUF2_VTS_TSABB(x) (((x) >> 14 ) & 0x1ff)
> +#define MT8173_CALIB_BUF0_DEGC_CALI(x) (((x) >> 1 ) & 0x3f)
> +#define MT8173_CALIB_BUF0_O_SLOPE(x) (((x) >> 26 ) & 0x3f)
> +
> +#define THERMAL_NAME "mtk-thermal"
> +
> +struct mtk_thermal;
> +
> +struct mtk_thermal_bank {
> + struct mtk_thermal *mt;
> + int id;
> +};
> +
> +struct mtk_thermal {
> + struct device *dev;
> + void __iomem *thermal_base;
> +
> + struct clk *clk_peri_therm;
> + struct clk *clk_auxadc;
> +
> + struct mtk_thermal_bank banks[MT8173_NUM_ZONES];
> +
> + struct mutex lock;
> +
> + /* Calibration values */
> + s32 adc_ge;
> + s32 degc_cali;
> + s32 o_slope;
> + s32 vts[MT8173_NUM_SENSORS];
> +
> + struct thermal_zone_device *tzd;
> +};
> +
> +struct mtk_thermal_bank_cfg {
> + unsigned int num_sensors;
> + unsigned int sensors[MT8173_NUM_SENSORS_PER_ZONE];
> +};
> +
> +static const int sensor_mux_values[MT8173_NUM_SENSORS] = { 0, 1, 2, 3, 16 };
> +
> +/*
> + * The MT8173 thermal controller has four banks. Each bank can read up to
> + * four temperature sensors simultaneously. The MT8173 has a total of 5
> + * temperature sensors. We use each bank to measure a certain area of the
> + * SoC. Since TS2 is located centrally in the SoC it is influenced by multiple
> + * areas, hence is used in different banks.
> + */
> +static const struct mtk_thermal_bank_cfg bank_data[] = {
> + {
> + .num_sensors = 2,
> + .sensors = { MT8173_TS2, MT8173_TS3 },
> + }, {
> + .num_sensors = 2,
> + .sensors = { MT8173_TS2, MT8173_TS4 },
> + }, {
> + .num_sensors = 3,
> + .sensors = { MT8173_TS1, MT8173_TS2, MT8173_TSABB },
> + }, {
> + .num_sensors = 1,
> + .sensors = { MT8173_TS2 },
> + },
> +};
> +
> +struct mtk_thermal_sense_point {
> + int msr;
> + int adcpnp;
> +};
> +
> +static const struct mtk_thermal_sense_point
> + sensing_points[MT8173_NUM_SENSORS_PER_ZONE] = {
> + {
> + .msr = TEMP_MSR0,
> + .adcpnp = TEMP_ADCPNP0,
> + }, {
> + .msr = TEMP_MSR1,
> + .adcpnp = TEMP_ADCPNP1,
> + }, {
> + .msr = TEMP_MSR2,
> + .adcpnp = TEMP_ADCPNP2,
> + }, {
> + .msr = TEMP_MSR3,
> + .adcpnp = TEMP_ADCPNP3,
> + },
> +};
> +
> +/**
> + * raw_to_mcelsius - convert a raw ADC value to mcelsius
> + * @mt: The thermal controller
> + * @raw: raw ADC value
> + *
> + * This converts the raw ADC value to mcelsius using the SoC specific
> + * calibration constants
> + */
> +static int raw_to_mcelsius(struct mtk_thermal *mt, int sensno, s32 raw)
> +{
> + s32 tmp;
> +
> + raw &= 0xfff;
> +
> + tmp = 203450520 << 3;
> + tmp /= 165 + mt->o_slope;
> + tmp /= 10000 + mt->adc_ge;
> + tmp *= raw - mt->vts[sensno] - 3350;
> + tmp >>= 3;
> +
> + return mt->degc_cali * 500 - tmp;
> +}
> +
> +/**
> + * mtk_thermal_get_bank - get bank
> + * @bank: The bank
> + *
> + * The bank registers are banked, we have to select a bank in the
> + * PTPCORESEL register to access it.
> + */
> +static void mtk_thermal_get_bank(struct mtk_thermal_bank *bank)
> +{
> + struct mtk_thermal *mt = bank->mt;
> + u32 val;
> +
> + mutex_lock(&mt->lock);
> +
> + val = readl(mt->thermal_base + PTPCORESEL);
> + val &= ~0xf;
> + val |= bank->id;
> + writel(val, mt->thermal_base + PTPCORESEL);
> +}
> +
> +/**
> + * mtk_thermal_put_bank - release bank
> + * @bank: The bank
> + *
> + * release a bank previously taken with mtk_thermal_get_bank,
> + */
> +static void mtk_thermal_put_bank(struct mtk_thermal_bank *bank)
> +{
> + struct mtk_thermal *mt = bank->mt;
> +
> + mutex_unlock(&mt->lock);
> +}
> +
> +/**
> + * mtk_thermal_bank_temperature - get the temperature of a bank
> + * @bank: The bank
> + *
> + * The temperature of a bank is considered the maximum temperature of
> + * the sensors associated to the bank.
> + */
> +static int mtk_thermal_bank_temperature(struct mtk_thermal_bank *bank)
> +{
> + struct mtk_thermal *mt = bank->mt;
> + int temp, i, max;
> + u32 raw;
> +
> + temp = max = INT_MIN;
> +
> + for (i = 0; i < bank_data[bank->id].num_sensors; i++) {
> + raw = readl(mt->thermal_base + sensing_points[i].msr);
> +
> + temp = raw_to_mcelsius(mt, bank_data[bank->id].sensors[i], raw);
> +
> + /*
> + * The first read of a sensor often contains very high bogus
> + * temperature value. Filter these out so that the system does
> + * not immediately shut down.
> + */
> + if (temp > 200000)
> + temp = 0;
> +
> + if (temp > max)
> + max = temp;
> + }
> +
> + return max;
> +}
> +
> +static int mtk_read_temp(void *data, int *temperature)
> +{
> + struct mtk_thermal *mt = data;
> + int i;
> + int tempmax = INT_MIN;
> +
> + for (i = 0; i < MT8173_NUM_ZONES; i++) {
> + struct mtk_thermal_bank *bank = &mt->banks[i];
> + int t;
> +
> + mtk_thermal_get_bank(bank);
> +
> + t = mtk_thermal_bank_temperature(bank);
> +
> + mtk_thermal_put_bank(bank);
> +
> + if (t > tempmax)
> + tempmax = t;

Would it be
tempmax = max_t(int, tempmax, mtk_thermal_bank_temperature(bank));
?

> + }
> +
> + *temperature = tempmax;
> +
> + return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops mtk_thermal_ops = {
> + .get_temp = mtk_read_temp,
> +};
> +
> +static void mtk_thermal_init_bank(struct mtk_thermal *mt, int num,
> + u32 apmixed_phys_base, u32 auxadc_phys_base)
> +{
> + struct mtk_thermal_bank *bank = &mt->banks[num];
> + const struct mtk_thermal_bank_cfg *cfg = &bank_data[num];
> + int i;
> +
> + bank->id = num;
> + bank->mt = mt;
> +
> + mtk_thermal_get_bank(bank);
> +
> + /* bus clock 66M counting unit is 12 * 15.15ns * 256 = 46.540us */
> + writel(TEMP_MONCTL1_PERIOD_UNIT(12), mt->thermal_base + TEMP_MONCTL1);
> +
> + /*
> + * filt interval is 1 * 46.540us = 46.54us,
> + * sen interval is 429 * 46.540us = 19.96ms
> + */
> + writel(TEMP_MONCTL2_FILTER_INTERVAL(1) |
> + TEMP_MONCTL2_SENSOR_INTERVAL(429),
> + mt->thermal_base + TEMP_MONCTL2);
> +
> + /* poll is set to 10u */
> + writel(TEMP_AHBPOLL_ADC_POLL_INTERVAL(768),
> + mt->thermal_base + TEMP_AHBPOLL);
> +
> + /* temperature sampling control, 1 sample */
> + writel(0x00000000, mt->thermal_base + TEMP_MSRCTL0);

0x0 like below ?

> +
> + /* exceed this polling time, IRQ would be inserted */
> + writel(0xffffffff, mt->thermal_base + TEMP_AHBTO);
> +
> + /* number of interrupts per event, 1 is enough */
> + writel(0x0, mt->thermal_base + TEMP_MONIDET0);
> + writel(0x0, mt->thermal_base + TEMP_MONIDET1);
> +
> + /*
> + * The MT8173 thermal controller does not have its own ADC. Instead it
> + * uses AHB bus accesses to control the AUXADC. To do this the thermal
> + * controller has to be programmed with the physical addresses of the
> + * AUXADC registers and with the various bit positions in the AUXADC.
> + * Also the thermal controller controls a mux in the APMIXEDSYS register
> + * space.
> + */
> +
> + /*
> + * this value will be stored to TEMP_PNPMUXADDR (TEMP_SPARE0)
> + * automatically by hw
> + */
> + writel(BIT(MT8173_TEMP_AUXADC_CHANNEL), mt->thermal_base + TEMP_ADCMUX);
> +
> + /* AHB address for auxadc mux selection */
> + writel(auxadc_phys_base + AUXADC_CON1_CLR_V,
> + mt->thermal_base + TEMP_ADCMUXADDR);
> +
> + /* AHB address for pnp sensor mux selection */
> + writel(apmixed_phys_base + APMIXED_SYS_TS_CON1,
> + mt->thermal_base + TEMP_PNPMUXADDR);
> +
> + /* AHB value for auxadc enable */
> + writel(BIT(MT8173_TEMP_AUXADC_CHANNEL), mt->thermal_base + TEMP_ADCEN);
> +
> + /* AHB address for auxadc enable (channel 0 immediate mode selected) */
> + writel(auxadc_phys_base + AUXADC_CON1_SET_V,
> + mt->thermal_base + TEMP_ADCENADDR);
> +
> + /* AHB address for auxadc valid bit */
> + writel(auxadc_phys_base + AUXADC_DATA(MT8173_TEMP_AUXADC_CHANNEL),
> + mt->thermal_base + TEMP_ADCVALIDADDR);
> +
> + /* AHB address for auxadc voltage output */
> + writel(auxadc_phys_base + AUXADC_DATA(MT8173_TEMP_AUXADC_CHANNEL),
> + mt->thermal_base + TEMP_ADCVOLTADDR);
> +
> + /* read valid & voltage are at the same register */
> + writel(0x0, mt->thermal_base + TEMP_RDCTRL);
> +
> + /* indicate where the valid bit is */
> + writel(TEMP_ADCVALIDMASK_VALID_HIGH | TEMP_ADCVALIDMASK_VALID_POS(12),
> + mt->thermal_base + TEMP_ADCVALIDMASK);
> +
> + /* no shift */
> + writel(0x0, mt->thermal_base + TEMP_ADCVOLTAGESHIFT);
> +
> + /* enable auxadc mux write transaction */
> + writel(TEMP_ADCWRITECTRL_ADC_MUX_WRITE,
> + mt->thermal_base + TEMP_ADCWRITECTRL);
> +
> + for (i = 0; i < cfg->num_sensors; i++)
> + writel(sensor_mux_values[cfg->sensors[i]],
> + mt->thermal_base + sensing_points[i].adcpnp);
> +
> + writel((1 << cfg->num_sensors) - 1, mt->thermal_base + TEMP_MONCTL0);
> +
> + writel(TEMP_ADCWRITECTRL_ADC_PNP_WRITE | TEMP_ADCWRITECTRL_ADC_MUX_WRITE,
> + mt->thermal_base + TEMP_ADCWRITECTRL);
> +
> + mtk_thermal_put_bank(bank);
> +}
> +
> +static u64 of_get_phys_base(struct device_node *np)
> +{
> + u64 size64;
> + const __be32 *regaddr_p;
> +
> + regaddr_p = of_get_address(np, 0, &size64, NULL);
> + if (!regaddr_p)
> + return OF_BAD_ADDR;
> +
> + return of_translate_address(np, regaddr_p);
> +}
> +
> +static int mtk_thermal_get_calibration_data(struct device *dev, struct mtk_thermal *mt)
> +{
> + struct nvmem_cell *cell;
> + u32 *buf;
> + size_t len;
> + int i, ret;
> +
> + /* Start with default values */
> + mt->adc_ge = 512;
> + for (i = 0; i < MT8173_NUM_SENSORS; i++)
> + mt->vts[i] = 260;
> + mt->degc_cali = 40;
> + mt->o_slope = 0;
> +
> + cell = nvmem_cell_get(dev, "calibration-data");
> + if (IS_ERR(cell)) {
> + if (PTR_ERR(cell) == -EPROBE_DEFER)
> + return PTR_ERR(cell);
> + return 0;
> + }
> +
> + buf = (u32 *)nvmem_cell_read(cell, &len);
> +
> + nvmem_cell_put(cell);
> +
> + if (IS_ERR(buf))
> + return PTR_ERR(buf);
> +
> + if (len < 3 * sizeof(u32)) {
> + dev_warn(dev, "invalid calibration data\n");
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + if (buf[0] & MT8173_CALIB_BUF0_VALID) {
> + mt->adc_ge = MT8173_CALIB_BUF1_ADC_GE(buf[1]);
> + mt->vts[MT8173_TS1] = MT8173_CALIB_BUF0_VTS_TS1(buf[0]);
> + mt->vts[MT8173_TS2] = MT8173_CALIB_BUF0_VTS_TS2(buf[0]);
> + mt->vts[MT8173_TS3] = MT8173_CALIB_BUF1_VTS_TS3(buf[1]);
> + mt->vts[MT8173_TS4] = MT8173_CALIB_BUF2_VTS_TS4(buf[2]);
> + mt->vts[MT8173_TSABB] = MT8173_CALIB_BUF2_VTS_TSABB(buf[2]);
> + mt->degc_cali = MT8173_CALIB_BUF0_DEGC_CALI(buf[0]);
> + mt->o_slope = MT8173_CALIB_BUF0_O_SLOPE(buf[0]);
> + } else {
> + dev_info(dev, "Device not calibrated, using default calibration values\n");
> + }
> +
> +out:
> + kfree(buf);
> +
> + return ret;
> +}
> +
> +static int mtk_thermal_probe(struct platform_device *pdev)
> +{
> + int ret, i;
> + struct device_node *auxadc, *apmixedsys, *np = pdev->dev.of_node;
> + struct mtk_thermal *mt;
> + struct resource *res;
> + u64 auxadc_phys_base, apmixed_phys_base;
> +
> + mt = devm_kzalloc(&pdev->dev, sizeof(*mt), GFP_KERNEL);
> + if (!mt)
> + return -ENOMEM;
> +
> + mt->clk_peri_therm = devm_clk_get(&pdev->dev, "therm");
> + if (IS_ERR(mt->clk_peri_therm))
> + return PTR_ERR(mt->clk_peri_therm);
> +
> + mt->clk_auxadc = devm_clk_get(&pdev->dev, "auxadc");
> + if (IS_ERR(mt->clk_auxadc))
> + return PTR_ERR(mt->clk_auxadc);
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + mt->thermal_base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(mt->thermal_base))
> + return PTR_ERR(mt->thermal_base);
> +
> + ret = mtk_thermal_get_calibration_data(&pdev->dev, mt);
> + if (ret)
> + return ret;
> +
> + mutex_init(&mt->lock);
> +
> + mt->dev = &pdev->dev;
> +
> + auxadc = of_parse_phandle(np, "mediatek,auxadc", 0);
> + if (!auxadc) {
> + dev_err(&pdev->dev, "missing auxadc node\n");
> + return -ENODEV;
> + }
> +
> + auxadc_phys_base = of_get_phys_base(auxadc);
> +
> + of_node_put(auxadc);
> +
> + if (auxadc_phys_base == OF_BAD_ADDR) {
> + dev_err(&pdev->dev, "Can't get auxadc phys address\n");
> + return -EINVAL;
> + }
> +
> + apmixedsys = of_parse_phandle(np, "mediatek,apmixedsys", 0);
> + if (!apmixedsys) {
> + dev_err(&pdev->dev, "missing apmixedsys node\n");
> + return -ENODEV;
> + }
> +
> + apmixed_phys_base = of_get_phys_base(apmixedsys);
> +
> + of_node_put(apmixedsys);
> +
> + if (apmixed_phys_base == OF_BAD_ADDR) {
> + dev_err(&pdev->dev, "Can't get auxadc phys address\n");
> + return -EINVAL;
> + }
> +
> + ret = clk_prepare_enable(mt->clk_auxadc);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't enable auxadc clk: %d\n", ret);
> + return ret;
> + }
> +
> + ret = device_reset(&pdev->dev);
> + if (ret)
> + goto err_disable_clk_auxadc;
> +
> + ret = clk_prepare_enable(mt->clk_peri_therm);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't enable peri clk: %d\n", ret);
> + goto err_disable_clk_auxadc;
> + }
> +
> + for (i = 0; i < MT8173_NUM_ZONES; i++)
> + mtk_thermal_init_bank(mt, i, apmixed_phys_base, auxadc_phys_base);
> +
> + platform_set_drvdata(pdev, mt);
> +
> + mt->tzd = thermal_zone_of_sensor_register(&pdev->dev, 0, mt,
> + &mtk_thermal_ops);
> + if (IS_ERR(mt->tzd))
> + goto err_register;
> +
> + return 0;
> +
> +err_register:
> + clk_disable_unprepare(mt->clk_peri_therm);
> +
> +err_disable_clk_auxadc:
> + clk_disable_unprepare(mt->clk_auxadc);
> +
> + return ret;
> +}
> +
> +static int mtk_thermal_remove(struct platform_device *pdev)
> +{
> + struct mtk_thermal *mt = platform_get_drvdata(pdev);
> +
> + thermal_zone_of_sensor_unregister(&pdev->dev, mt->tzd);
> +
> + clk_disable_unprepare(mt->clk_peri_therm);
> + clk_disable_unprepare(mt->clk_auxadc);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id mtk_thermal_of_match[] = {
> + {
> + .compatible = "mediatek,mt8173-thermal",
> + }, {
> + },
> +};
> +
> +static struct platform_driver mtk_thermal_driver = {
> + .probe = mtk_thermal_probe,
> + .remove = mtk_thermal_remove,
> + .driver = {
> + .name = THERMAL_NAME,
> + .of_match_table = mtk_thermal_of_match,
> + },
> +};
> +
> +module_platform_driver(mtk_thermal_driver);
> +
> +MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de");

And Author in the head?

--
With Best Regards,
Andy Shevchenko