diff mbox

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

Message ID 1447064013-13026-3-git-send-email-s.hauer@pengutronix.de (mailing list archive)
State New, archived
Headers show

Commit Message

Sascha Hauer Nov. 9, 2015, 10:13 a.m. UTC 
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.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 drivers/thermal/Kconfig       |   8 +
 drivers/thermal/Makefile      |   1 +
 drivers/thermal/mtk_thermal.c | 619 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 628 insertions(+)
 create mode 100644 drivers/thermal/mtk_thermal.c

Comments

Andy Shevchenko Nov. 9, 2015, 2:39 p.m. UTC | #1 
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?
Javi Merino Nov. 10, 2015, 12:05 p.m. UTC | #2 
On Mon, Nov 09, 2015 at 11:13:32AM +0100, Sascha Hauer 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.
> 
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> ---
>  drivers/thermal/Kconfig       |   8 +
>  drivers/thermal/Makefile      |   1 +
>  drivers/thermal/mtk_thermal.c | 619 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 628 insertions(+)
>  create mode 100644 drivers/thermal/mtk_thermal.c
> 
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 5aabc4b..503448a 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -348,6 +348,14 @@ config INTEL_PCH_THERMAL
>  	  Thermal reporting device will provide temperature reading,
>  	  programmable trip points and other information.
>  
> +config MTK_THERMAL
> +	tristate "Temperature sensor driver for mediatek SoCs"
> +	depends on ARCH_MEDIATEK || COMPILE_TEST
> +	default y
> +	help
> +	  Enable this option if you want to have support for thermal management
> +	  controller present in Mediatek SoCs
> +
>  menu "Texas Instruments thermal drivers"
>  depends on ARCH_HAS_BANDGAP || COMPILE_TEST
>  source "drivers/thermal/ti-soc-thermal/Kconfig"
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 26f1608..5f979e7 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -45,3 +45,4 @@ obj-$(CONFIG_INTEL_PCH_THERMAL)	+= intel_pch_thermal.o
>  obj-$(CONFIG_ST_THERMAL)	+= st/
>  obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra_soctherm.o
>  obj-$(CONFIG_HISI_THERMAL)     += hisi_thermal.o
> +obj-$(CONFIG_MTK_THERMAL)	+= mtk_thermal.o
> diff --git a/drivers/thermal/mtk_thermal.c b/drivers/thermal/mtk_thermal.c
> new file mode 100644
> index 0000000..2d2e97c
> --- /dev/null
> +++ b/drivers/thermal/mtk_thermal.c
> @@ -0,0 +1,619 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + * Author: Hanyi Wu <hanyi.wu@mediatek.com>
> + *
> + * 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.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#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);

IIUIC, when you had multiple thermal zones
mtk_thermal_bank_temperature() made sense, but now it looks like
you're just doing the maximum of all sensors.  Why bother with the
banks any more?  Aren't you just calculating the maximum of all
sensors?  As TS2 is present in all banks, there's no point in reading
it four times just to get the maximum of all sensors.

> +		mtk_thermal_put_bank(bank);
> +
> +		if (t > tempmax)
> +			tempmax = t;
> +	}
> +
> +	*temperature = tempmax;
> +
> +	return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops mtk_thermal_ops = {
> +	.get_temp = mtk_read_temp,
> +};

Cheers,
Javi
Eduardo Valentin Nov. 10, 2015, 6:26 p.m. UTC | #3 
On Tue, Nov 10, 2015 at 12:05:54PM +0000, Javi Merino wrote:
> On Mon, Nov 09, 2015 at 11:13:32AM +0100, Sascha Hauer wrote:

<cut>

> > +
> > +/*
> > + * 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 },
> > +	},
> > +};

Would it make sense to simply expose all sensors and let the
configuration of their aggregation be done by DT?

There is already ongoing effort to get aggregation functions
generalized.

> > +
> > +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);
> 
> IIUIC, when you had multiple thermal zones
> mtk_thermal_bank_temperature() made sense, but now it looks like
> you're just doing the maximum of all sensors.  Why bother with the
> banks any more?  Aren't you just calculating the maximum of all
> sensors?  As TS2 is present in all banks, there's no point in reading
> it four times just to get the maximum of all sensors.
> 

Yeah, agreed here. If that is your intention, maybe read each sensor one
time, then compute the max of each subset from memory instead.

> > +		mtk_thermal_put_bank(bank);
> > +
> > +		if (t > tempmax)
> > +			tempmax = t;
> > +	}
> > +
> > +	*temperature = tempmax;
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct thermal_zone_of_device_ops mtk_thermal_ops = {
> > +	.get_temp = mtk_read_temp,
> > +};
> 
> Cheers,
> Javi
>
Sascha Hauer Nov. 11, 2015, 7:27 a.m. UTC | #4 
On Tue, Nov 10, 2015 at 10:26:30AM -0800, Eduardo Valentin wrote:
> On Tue, Nov 10, 2015 at 12:05:54PM +0000, Javi Merino wrote:
> > On Mon, Nov 09, 2015 at 11:13:32AM +0100, Sascha Hauer wrote:
> 
> <cut>
> 
> > > +
> > > +/*
> > > + * 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 },
> > > +	},
> > > +};
> 
> Would it make sense to simply expose all sensors and let the
> configuration of their aggregation be done by DT?

This particular layout has been chosen because there's also the Smart
Voltage Scaler (SVS) in the SoC. The SVS uses the same banks for
measuring temperatures. I don't know the details yet, I just asked the
Mediatek guys.

> 
> There is already ongoing effort to get aggregation functions
> generalized.

Do you have any pointers? I haven't seen these efforts yet.

> > > +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);
> > 
> > IIUIC, when you had multiple thermal zones
> > mtk_thermal_bank_temperature() made sense, but now it looks like
> > you're just doing the maximum of all sensors.  Why bother with the
> > banks any more?  Aren't you just calculating the maximum of all
> > sensors?  As TS2 is present in all banks, there's no point in reading
> > it four times just to get the maximum of all sensors.
> > 
> 
> Yeah, agreed here. If that is your intention, maybe read each sensor one
> time, then compute the max of each subset from memory instead.

I would have done that if there wasn't this SVS engine. I'll ask
internally what the constraint of this SVS engine actually are and let
you know.

Sascha
Javi Merino Nov. 11, 2015, 9:40 a.m. UTC | #5 
On Wed, Nov 11, 2015 at 08:27:47AM +0100, Sascha Hauer wrote:
> On Tue, Nov 10, 2015 at 10:26:30AM -0800, Eduardo Valentin wrote:
> > On Tue, Nov 10, 2015 at 12:05:54PM +0000, Javi Merino wrote:
> > > On Mon, Nov 09, 2015 at 11:13:32AM +0100, Sascha Hauer wrote:
> > 
> > <cut>
> > 
> > > > +
> > > > +/*
> > > > + * 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 },
> > > > +	},
> > > > +};
> > 
> > Would it make sense to simply expose all sensors and let the
> > configuration of their aggregation be done by DT?
> 
> This particular layout has been chosen because there's also the Smart
> Voltage Scaler (SVS) in the SoC. The SVS uses the same banks for
> measuring temperatures. I don't know the details yet, I just asked the
> Mediatek guys.
> 
> > 
> > There is already ongoing effort to get aggregation functions
> > generalized.
> 
> Do you have any pointers? I haven't seen these efforts yet.

Hierarchical thermal zones
http://thread.gmane.org/gmane.linux.power-management.general/67785

You could keep your thermal zones per bank and then use the
hierarchical thermal zone to create a thermal zone that calculates the
maximum of all banks.  You can put the trip points in this thermal
zone.

> > > > +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);
> > > 
> > > IIUIC, when you had multiple thermal zones
> > > mtk_thermal_bank_temperature() made sense, but now it looks like
> > > you're just doing the maximum of all sensors.  Why bother with the
> > > banks any more?  Aren't you just calculating the maximum of all
> > > sensors?  As TS2 is present in all banks, there's no point in reading
> > > it four times just to get the maximum of all sensors.
> > > 
> > 
> > Yeah, agreed here. If that is your intention, maybe read each sensor one
> > time, then compute the max of each subset from memory instead.
> 
> I would have done that if there wasn't this SVS engine. I'll ask
> internally what the constraint of this SVS engine actually are and let
> you know.
> 
> Sascha
> 
> 
> -- 
> Pengutronix e.K.                           |                             |
> Industrial Linux Solutions                 | http://www.pengutronix.de/  |
> Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |
>
Sascha Hauer Nov. 13, 2015, 10:09 a.m. UTC | #6 
On Wed, Nov 11, 2015 at 08:27:47AM +0100, Sascha Hauer wrote:
> On Tue, Nov 10, 2015 at 10:26:30AM -0800, Eduardo Valentin wrote:
> > On Tue, Nov 10, 2015 at 12:05:54PM +0000, Javi Merino wrote:
> > > On Mon, Nov 09, 2015 at 11:13:32AM +0100, Sascha Hauer wrote:
> > 
> > <cut>
> > 
> > > > +
> > > > +/*
> > > > + * 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 },
> > > > +	},
> > > > +};
> > 
> > Would it make sense to simply expose all sensors and let the
> > configuration of their aggregation be done by DT?
> 
> This particular layout has been chosen because there's also the Smart
> Voltage Scaler (SVS) in the SoC. The SVS uses the same banks for
> measuring temperatures. I don't know the details yet, I just asked the
> Mediatek guys.

Ok, the job of the SVS is to always pick the best voltage for a given
CPU frequency based on the temperature of the CPU cluster. How I
understand it the SVS engine automatically reads temperatures from bank0
for the first CPU cluster and from bank1 for the second CPU cluster. For
this to work we are not free to assign the sensors to the banks
arbitrarily.

I was told that controlling the CPU frequency the performance is better
if we use the maximum temperature of the whole die rather than the
temperature of individual clusters.

I would prefer to keep the sensor/bank association like it currently is
as it allows for easy SVS engine integration. Also I would prefer to
expose a single thermal zone for now, it will be easier to add
additional zones later than it is to remove them later once we have
exposed them to the device tree.

Is that ok with you?

Sascha
Javi Merino Nov. 13, 2015, 11:26 a.m. UTC | #7 
On Fri, Nov 13, 2015 at 11:09:12AM +0100, Sascha Hauer wrote:
> On Wed, Nov 11, 2015 at 08:27:47AM +0100, Sascha Hauer wrote:
> > On Tue, Nov 10, 2015 at 10:26:30AM -0800, Eduardo Valentin wrote:
> > > On Tue, Nov 10, 2015 at 12:05:54PM +0000, Javi Merino wrote:
> > > > On Mon, Nov 09, 2015 at 11:13:32AM +0100, Sascha Hauer wrote:
> > > 
> > > <cut>
> > > 
> > > > > +
> > > > > +/*
> > > > > + * 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 },
> > > > > +	},
> > > > > +};
> > > 
> > > Would it make sense to simply expose all sensors and let the
> > > configuration of their aggregation be done by DT?
> > 
> > This particular layout has been chosen because there's also the Smart
> > Voltage Scaler (SVS) in the SoC. The SVS uses the same banks for
> > measuring temperatures. I don't know the details yet, I just asked the
> > Mediatek guys.
> 
> Ok, the job of the SVS is to always pick the best voltage for a given
> CPU frequency based on the temperature of the CPU cluster. How I
> understand it the SVS engine automatically reads temperatures from bank0
> for the first CPU cluster and from bank1 for the second CPU cluster. For
> this to work we are not free to assign the sensors to the banks
> arbitrarily.
> 
> I was told that controlling the CPU frequency the performance is better
> if we use the maximum temperature of the whole die rather than the
> temperature of individual clusters.
> 
> I would prefer to keep the sensor/bank association like it currently is
> as it allows for easy SVS engine integration. Also I would prefer to
> expose a single thermal zone for now, it will be easier to add
> additional zones later than it is to remove them later once we have
> exposed them to the device tree.
> 
> Is that ok with you?

Fair enough.  I agree that it's easier to add thermal zones in the
future than to remove it.  Thanks for the explanation.

Cheers,
Javi
Sascha Hauer Nov. 18, 2015, 8:11 a.m. UTC | #8 
On Mon, Nov 09, 2015 at 04:39:37PM +0200, Andy Shevchenko wrote:
> 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));
> ?

Yes, even max() works here. Fixed.

> > +
> > +       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 ?

Ok.

> > +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?

Added.

Thanks for reviewing.

Sascha
Sascha Hauer Nov. 18, 2015, 8:18 a.m. UTC | #9 
On Fri, Nov 13, 2015 at 11:26:37AM +0000, Javi Merino wrote:
> On Fri, Nov 13, 2015 at 11:09:12AM +0100, Sascha Hauer wrote:
> > On Wed, Nov 11, 2015 at 08:27:47AM +0100, Sascha Hauer wrote:
> > > On Tue, Nov 10, 2015 at 10:26:30AM -0800, Eduardo Valentin wrote:
> > > > On Tue, Nov 10, 2015 at 12:05:54PM +0000, Javi Merino wrote:
> > > > > On Mon, Nov 09, 2015 at 11:13:32AM +0100, Sascha Hauer wrote:
> > > > 
> > > > <cut>
> > > > 
> > > > > > +
> > > > > > +/*
> > > > > > + * 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 },
> > > > > > +	},
> > > > > > +};
> > > > 
> > > > Would it make sense to simply expose all sensors and let the
> > > > configuration of their aggregation be done by DT?
> > > 
> > > This particular layout has been chosen because there's also the Smart
> > > Voltage Scaler (SVS) in the SoC. The SVS uses the same banks for
> > > measuring temperatures. I don't know the details yet, I just asked the
> > > Mediatek guys.
> > 
> > Ok, the job of the SVS is to always pick the best voltage for a given
> > CPU frequency based on the temperature of the CPU cluster. How I
> > understand it the SVS engine automatically reads temperatures from bank0
> > for the first CPU cluster and from bank1 for the second CPU cluster. For
> > this to work we are not free to assign the sensors to the banks
> > arbitrarily.
> > 
> > I was told that controlling the CPU frequency the performance is better
> > if we use the maximum temperature of the whole die rather than the
> > temperature of individual clusters.
> > 
> > I would prefer to keep the sensor/bank association like it currently is
> > as it allows for easy SVS engine integration. Also I would prefer to
> > expose a single thermal zone for now, it will be easier to add
> > additional zones later than it is to remove them later once we have
> > exposed them to the device tree.
> > 
> > Is that ok with you?
> 
> Fair enough.  I agree that it's easier to add thermal zones in the
> future than to remove it.  Thanks for the explanation.

I added this comment to make this a bit clearer for the next version:

/*
 * The thermal core only gets the maximum temperature of all banks, so
 * the bank concept wouldn't be necessary here. However, the SVS (Smart
 * Voltage Scaling) unit makes its decisions based on the same bank
 * data, and this indeed needs the temperatures of the individual
 * banks
 * for making better decisions.
 */
diff mbox

Patch

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 5aabc4b..503448a 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -348,6 +348,14 @@  config INTEL_PCH_THERMAL
 	  Thermal reporting device will provide temperature reading,
 	  programmable trip points and other information.
 
+config MTK_THERMAL
+	tristate "Temperature sensor driver for mediatek SoCs"
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	default y
+	help
+	  Enable this option if you want to have support for thermal management
+	  controller present in Mediatek SoCs
+
 menu "Texas Instruments thermal drivers"
 depends on ARCH_HAS_BANDGAP || COMPILE_TEST
 source "drivers/thermal/ti-soc-thermal/Kconfig"
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 26f1608..5f979e7 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -45,3 +45,4 @@  obj-$(CONFIG_INTEL_PCH_THERMAL)	+= intel_pch_thermal.o
 obj-$(CONFIG_ST_THERMAL)	+= st/
 obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra_soctherm.o
 obj-$(CONFIG_HISI_THERMAL)     += hisi_thermal.o
+obj-$(CONFIG_MTK_THERMAL)	+= mtk_thermal.o
diff --git a/drivers/thermal/mtk_thermal.c b/drivers/thermal/mtk_thermal.c
new file mode 100644
index 0000000..2d2e97c
--- /dev/null
+++ b/drivers/thermal/mtk_thermal.c
@@ -0,0 +1,619 @@ 
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ * Author: Hanyi Wu <hanyi.wu@mediatek.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#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;
+	}
+
+	*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);
+
+	/* 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");
+MODULE_DESCRIPTION("Mediatek thermal driver");
+MODULE_LICENSE("GPL v2");