Add VTM thermal support. In the Voltage Thermal Management Module(VTM), K3 J72XX supplies a voltage reference and a temperature sensor feature that are gathered in the band gap voltage and temperature sensor (VBGAPTS) module. The band gap provides current and voltage reference for its internal circuits and other analog IP blocks. The analog-to-digital converter (ADC) produces an output value that is proportional to the silicon temperature. Currently reading temperatures only is supported. There are no active/passive cooling agent supported. J721e SoCs have errata i2128: https://www.ti.com/lit/pdf/sprz455 The VTM Temperature Monitors (TEMPSENSORs) are trimmed during production, with the resulting values stored in software-readable registers. Software should use these register values when translating the Temperature Monitor output codes to temperature values. It has an involved workaround. Software needs to read the error codes for -40C, 30C, 125C from the efuse for each device & derive a new look up table for adc to temperature conversion. Involved calculating slopes & constants using 3 different straight line equations with adc refernce codes as the y-axis & error codes in the x-axis. -40C to 30C 30C to 125C 125C to 150C With the above 2 line equations we derive the full look-up table to workaround the errata i2128 for j721e SoC. Tested temperature reading on J721e SoC & J7200 SoC. [daniel.lezcano@xxxxxxxxxx: Generate look-up tables run-time] Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> Signed-off-by: Keerthy <j-keerthy@xxxxxx> --- Changes in v3: * Removed static look up tables & added functions to dynamically generate them. Thanks Daniel! Saved 12KB of static data & almost 200 lines of driver code. drivers/thermal/Makefile | 2 +- drivers/thermal/k3_j72xx_bandgap.c | 635 +++++++++++++++++++++++++++++ 2 files changed, 636 insertions(+), 1 deletion(-) create mode 100644 drivers/thermal/k3_j72xx_bandgap.c diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 82fc3e616e54..6dcaf2028ddc 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -28,7 +28,7 @@ thermal_sys-$(CONFIG_CPU_IDLE_THERMAL) += cpuidle_cooling.o # devfreq cooling thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o -obj-$(CONFIG_K3_THERMAL) += k3_bandgap.o +obj-$(CONFIG_K3_THERMAL) += k3_bandgap.o k3_j72xx_bandgap.o # platform thermal drivers obj-y += broadcom/ obj-$(CONFIG_THERMAL_MMIO) += thermal_mmio.o diff --git a/drivers/thermal/k3_j72xx_bandgap.c b/drivers/thermal/k3_j72xx_bandgap.c new file mode 100644 index 000000000000..a871aa619e58 --- /dev/null +++ b/drivers/thermal/k3_j72xx_bandgap.c @@ -0,0 +1,635 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * TI Bandgap temperature sensor driver for J72XX SoC Family + * + * Copyright (C) 2021 Texas Instruments Incorporated - http://www.ti.com/ + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/pm_runtime.h> +#include <linux/err.h> +#include <linux/types.h> +#include <linux/spinlock.h> +#include <linux/of_platform.h> +#include <linux/io.h> +#include <linux/thermal.h> +#include <linux/of.h> +#include <linux/delay.h> +#include <linux/math.h> +#include <linux/slab.h> + +#define K3_VTM_DEVINFO_PWR0_OFFSET 0x4 +#define K3_VTM_DEVINFO_PWR0_CVD_CT_MASK 0xf +#define K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK 0xf0 +#define K3_VTM_TMPSENS0_CTRL_OFFSET 0x300 +#define K3_VTM_MISC_CTRL_OFFSET 0xc +#define K3_VTM_TMPSENS_STAT_OFFSET 0x8 +#define K3_VTM_ANYMAXT_OUTRG_ALERT_EN 0x1 +#define K3_VTM_MISC_CTRL2_OFFSET 0x10 +#define K3_VTM_REGS_PER_TS 0x10 +#define K3_VTM_TS_STAT_DTEMP_MASK 0x3ff +#define K3_VTM_MAX_NUM_TS 8 +#define K3_VTM_TMPSENS_CTRL_CBIASSEL BIT(0) +#define K3_VTM_TMPSENS_CTRL_SOC BIT(5) +#define K3_VTM_TMPSENS_CTRL_CLRZ BIT(6) +#define K3_VTM_TMPSENS_CTRL_CLKON_REQ BIT(7) +#define K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN BIT(11) + +#define K3_VTM_CORRECTION_TEMP_CNT 3 + +#define K3_VTM_ADC_BEGIN_VAL 6 +#define K3_VTM_ADC_END_VAL 944 + +#define MINUS40CREF 5 +#define PLUS30CREF 253 +#define PLUS125CREF 730 +#define PLUS150CREF 940 + +#define MAX_TEMP 123000 +#define COOL_DOWN_TEMP 105000 + +//#define DEBUG_VTM + +static int *ref_table; +static int *derived_table; + +s64 golden_factors[] = { + -490019999999999936, + 3251200000000000, + -1705800000000, + 603730000, + -92627, +}; + +s64 pvt_wa_factors[] = { + -415230000000000000, + 3126600000000000, + -1157800000000, +}; + +static s64 int_power(unsigned long long base, unsigned int exp) +{ + s64 result = 1; + + while (exp) { + if (exp & 1) + result *= base; + exp >>= 1; + base *= base; + } + + return result; +} + +static int compute_value(int index, s64 *factors, int nr_factors, int reduction) +{ + s64 value = 0; + int i; + + for (i = 0; i < nr_factors; i++) + value += factors[i] * int_power(index, i); + + return (int)(value / int_power(10, reduction)); +} + +void init_table(bool wa, int *mytable) +{ + s64 *factors; + const int size = 1024; + int factors_size; + int i; + + if (wa) { + factors_size = 3; + factors = pvt_wa_factors; + } else { + factors_size = 5; + factors = golden_factors; + } + + for (i = 0; i < size; i++) + mytable[i] = compute_value(i, factors, factors_size, 13); +} + +static void fill_table(int err1, int err2, int ref1, int ref2, int idx1, + int idx2) +{ + int m, c, num, den, i, err; + + /** + * Calculate the slope with adc values read from the register + * as the y-axis param and err in adc value as x-axis param + */ + if (err1 != err2) { + num = ref2 - ref1; + den = err2 - err1; + m = num / den; + c = ref2 - m * err2; + for (i = idx1; i <= idx2; i++) { + err = (i - c) / m; + if (((i + err1) < 0) || ((i + err1) > 1023)) + continue; + derived_table[i] = ref_table[i + err]; + } + } else { /* Constant error take care of divide by zero */ + for (i = idx1; i < idx2; i++) { + if (((i + err1) < 0) || ((i + err1) > 1023)) + continue; + derived_table[i] = ref_table[i + err1]; + } + } +} + +static int prep_lookup_table(int minus40cerr, int plus30cerr, int plus125cerr, + int plus150cerr) +{ + int start_temp, inc, i; + + /* Fill up the lookup table region -40C to +30C */ + fill_table(minus40cerr, plus30cerr, MINUS40CREF, PLUS30CREF, 0, + PLUS30CREF); + /* Fill up the lookup table region +30C to +125C */ + fill_table(plus30cerr, plus125cerr, PLUS30CREF, PLUS125CREF, PLUS30CREF, + PLUS125CREF); + /* Fill up the lookup table region +125C to +150C */ + fill_table(plus125cerr, plus150cerr, PLUS125CREF, PLUS150CREF, PLUS125CREF, + PLUS150CREF); + + /* Get to the first valid temperature */ + i = 0; + while (!derived_table[i]) + i++; + + start_temp = i; + /* + * Get to the last zero index and back fill the temperature for + * sake of continuity + */ + if (i) { + /* 300 milli celsius steps */ + while (i--) + derived_table[i] = derived_table[i + 1] - 300; + /* case 0 */ + derived_table[i] = derived_table[i + 1] - 300; + } + + /* + * Fill the last trailing 0s which are unfilled with increments of + * 100 milli celsius till 1023 code + */ + i = 1023; + while (!derived_table[i]) + i--; + + i++; + inc = 1; + while (i < 1024) { + derived_table[i] = derived_table[i - 1] + inc * 100; + i++; + } + + return 0; +} + +struct k3_thermal_data; + +struct k3_j72xx_bandgap { + struct device *dev; + void __iomem *base; + void __iomem *cfg2_base; + void __iomem *fuse_base; + const struct k3_j72xx_bandgap_data *conf; + spinlock_t lock; /* shields this struct */ + int ts_cnt; + struct k3_thermal_data *ts_data[K3_VTM_MAX_NUM_TS]; +}; + +/* common data structures */ +struct k3_thermal_data { + struct thermal_zone_device *ti_thermal; + struct thermal_cooling_device *cool_dev; + struct k3_j72xx_bandgap *bgp; + enum thermal_device_mode mode; + int sensor_id; + u32 ctrl_offset; + u32 stat_offset; + int prev_temp; + int ct_offsets[K3_VTM_CORRECTION_TEMP_CNT]; + int ct_bm[K3_VTM_CORRECTION_TEMP_CNT]; + int ref_adc_val[3]; + int act_adc_val[3]; + int slope[2]; + int coeff[2]; +}; + +int two_cmp(int tmp, int mask) +{ + tmp = ~(tmp); + tmp &= mask; + tmp += 1; + + /* Return negative value */ + return (0 - tmp); +} + +static unsigned int vtm_get_best_value(unsigned int s0, unsigned int s1, + unsigned int s2) +{ + int d01 = abs(s0 - s1); + int d02 = abs(s0 - s2); + int d12 = abs(s1 - s2); + + if (d01 <= d02 && d01 <= d12) + return (s0 + s1) / 2; + + if (d02 <= d01 && d02 <= d12) + return (s0 + s2) / 2; + + return (s1 + s2) / 2; +} + +static inline int k3_bgp_read_temp(struct k3_thermal_data *devdata, + int *temp) +{ + struct k3_j72xx_bandgap *bgp; + unsigned int dtemp, s0, s1, s2; + + bgp = devdata->bgp; + /* + * Errata is applicable for am654 pg 1.0 silicon/J7ES. There + * is a variation of the order for certain degree centigrade on AM654. + * Work around that by getting the average of two closest + * readings out of three readings everytime we want to + * report temperatures. + * + * Errata workaround. + */ + s0 = readl(bgp->base + devdata->stat_offset) & + K3_VTM_TS_STAT_DTEMP_MASK; + s1 = readl(bgp->base + devdata->stat_offset) & + K3_VTM_TS_STAT_DTEMP_MASK; + s2 = readl(bgp->base + devdata->stat_offset) & + K3_VTM_TS_STAT_DTEMP_MASK; + dtemp = vtm_get_best_value(s0, s1, s2); + + if (dtemp < 0 || dtemp > 1023) + return -EINVAL; + + *temp = derived_table[dtemp]; + + return 0; +} + +/* Get temperature callback function for thermal zone */ +static int k3_thermal_get_temp(void *devdata, int *temp) +{ + struct k3_thermal_data *data = devdata; + int ret = 0; + + ret = k3_bgp_read_temp(data, temp); + if (ret) + return ret; + + data->prev_temp = *temp; + + return ret; +} + +static const struct thermal_zone_of_device_ops k3_of_thermal_ops = { + .get_temp = k3_thermal_get_temp, +}; + +static int k3_j72xx_bandgap_temp_to_adc_code(int temp) +{ + int low = 0, high = 1023, mid; + + if (temp > 160000 || temp < -50000) + return -EINVAL; + + /* Binary search to find the adc code */ + while (low < (high - 1)) { + mid = (low + high) / 2; + if (temp <= derived_table[mid]) + high = mid; + else + low = mid; + } + + return mid; +} + +static void get_efuse_values(int id, struct k3_thermal_data *data, int *err, + struct k3_j72xx_bandgap *bgp) +{ + int i, tmp, pow; + + /* Populate efuse reg offsets & Bit masks for -40C, 30C, 125C */ + switch (id) { + case 0: + data->ct_offsets[0] = 0x0; + data->ct_offsets[1] = 0x8; + data->ct_offsets[2] = 0x4; + data->ct_bm[0] = 0x3f; + data->ct_bm[1] = 0x1fe000; + data->ct_bm[2] = 0x1ff; + break; + + case 1: + data->ct_offsets[0] = 0x0; + data->ct_offsets[1] = 0x8; + data->ct_offsets[2] = 0x4; + data->ct_bm[0] = 0xfc0; + data->ct_bm[1] = 0x1fe00000; + data->ct_bm[2] = 0x3fe00; + break; + + case 2: + data->ct_offsets[0] = 0x0; + data->ct_offsets[1] = -1; + data->ct_offsets[2] = 0x4; + data->ct_bm[0] = 0x3f000; + data->ct_bm[1] = 0x7f800000; + data->ct_bm[2] = 0x7fc0000; + break; + + case 3: + data->ct_offsets[0] = 0x0; + data->ct_offsets[1] = 0xC; + data->ct_offsets[2] = -1; /* Spread across 2 registers */ + data->ct_bm[0] = 0xfc0000; + data->ct_bm[1] = 0x1fe0; + data->ct_bm[2] = 0x1f800000; + break; + + case 4: + data->ct_offsets[0] = 0x0; + data->ct_offsets[1] = 0xc; + data->ct_offsets[2] = 0x8; + data->ct_bm[0] = 0x3f000000; + data->ct_bm[1] = 0x1fe000; + data->ct_bm[2] = 0x1ff0; + break; + } + + for (i = 0; i < 3; i++) { + /* Extract the offset value using bit-mask */ + if (data->ct_offsets[i] == -1 && i == 1) { + /* 25C offset Case of Sensor 2 split between 2 regs */ + tmp = (readl(bgp->fuse_base + 0x8) & 0xE0000000) >> (29); + tmp |= ((readl(bgp->fuse_base + 0xC) & 0x1F) << 3); + pow = tmp & 0x80; + } else if (data->ct_offsets[i] == -1 && i == 2) { + /* 125C Case of Sensor 3 split between 2 regs */ + tmp = (readl(bgp->fuse_base + 0x4) & 0xF8000000) >> (27); + tmp |= ((readl(bgp->fuse_base + 0x8) & 0xF) << 5); + pow = tmp & 0x100; + } else { + tmp = readl(bgp->fuse_base + data->ct_offsets[i]); + tmp &= data->ct_bm[i]; + tmp = tmp >> __ffs(data->ct_bm[i]); + + /* Obtain the sign bit pow*/ + pow = data->ct_bm[i] >> __ffs(data->ct_bm[i]); + pow += 1; + pow /= 2; + } + + /* Check for negative value */ + if (tmp & pow) { + /* 2's complement value */ + tmp = two_cmp(tmp, data->ct_bm[i] >> __ffs(data->ct_bm[i])); + } + err[i] = tmp; + } +} + +#ifdef DEBUG_VTM +static void print_look_up_table(struct device *dev) +{ + int i; + + dev_info(dev, "The contents of derived array\n"); + dev_info(dev, "Code Temperaturei\n"); + for (i = 0; i <= 1023; i++) + dev_info(dev, "%d %d\n", i, derived_table[i]); +} +#endif + +static const struct of_device_id of_k3_j72xx_bandgap_match[]; + +struct k3_j72xx_bandgap_j72xx_data { + unsigned int workaround; +}; + +static int k3_j72xx_bandgap_probe(struct platform_device *pdev) +{ + int ret = 0, cnt, val, id, reg_cnt = 0, j, table_size = 1024; + int err[3], high_max, low_max; + struct resource *res; + struct device *dev = &pdev->dev; + struct k3_j72xx_bandgap *bgp; + struct k3_thermal_data *data; + int workaround_needed = 0; + const struct of_device_id *of_id; + const struct k3_j72xx_bandgap_j72xx_data *driver_data; + + bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL); + if (!bgp) + return -ENOMEM; + + bgp->dev = dev; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + bgp->base = devm_ioremap_resource(dev, res); + if (IS_ERR(bgp->base)) + return PTR_ERR(bgp->base); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + bgp->cfg2_base = devm_ioremap_resource(dev, res); + if (IS_ERR(bgp->cfg2_base)) + return PTR_ERR(bgp->cfg2_base); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 2); + bgp->fuse_base = devm_ioremap_resource(dev, res); + if (IS_ERR(bgp->fuse_base)) + return PTR_ERR(bgp->fuse_base); + + of_id = of_match_device(of_k3_j72xx_bandgap_match, &pdev->dev); + if (of_id) { + driver_data = of_id->data; + workaround_needed = driver_data->workaround; + } + + pm_runtime_enable(dev); + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + pm_runtime_put_noidle(dev); + pm_runtime_disable(dev); + return ret; + } + + /* Get the sensor count in the VTM */ + val = readl(bgp->base + K3_VTM_DEVINFO_PWR0_OFFSET); + cnt = val & K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK; + cnt >>= __ffs(K3_VTM_DEVINFO_PWR0_TEMPSENS_CT_MASK); + bgp->ts_cnt = cnt; + + data = devm_kcalloc(bgp->dev, cnt, sizeof(*data), GFP_KERNEL); + if (!data) { + ret = -ENOMEM; + goto err_alloc; + } + + ref_table = devm_kzalloc(bgp->dev, sizeof(*ref_table) * table_size, + GFP_KERNEL); + if (!ref_table) { + ret = -ENOMEM; + goto err_alloc; + } + + derived_table = devm_kzalloc(bgp->dev, sizeof(*derived_table) * table_size, + GFP_KERNEL); + if (!derived_table) { + ret = -ENOMEM; + goto err_alloc; + } + + /* Workaround not needed if bit30/bit31 is set even for J721e */ + if (workaround_needed && (readl(bgp->fuse_base + 0x0) & 0xc0000000) == 0xc0000000) + workaround_needed = false; + + if (!workaround_needed) { + dev_info(bgp->dev, "work around NOT needed!!\n"); + init_table(false, ref_table); + } else { + dev_info(bgp->dev, "work around needed!!\n"); + init_table(true, ref_table); + } + + /* Register the thermal sensors */ + for (id = 0; id < cnt; id++) { + data[id].sensor_id = id; + data[id].bgp = bgp; + data[id].ctrl_offset = K3_VTM_TMPSENS0_CTRL_OFFSET + id * 0x20; + data[id].stat_offset = data[id].ctrl_offset + + K3_VTM_TMPSENS_STAT_OFFSET; + + if (!workaround_needed) + goto prepare_lookup; + /* ref adc values for -40C, 30C & 125C respectively */ + data[id].ref_adc_val[0] = MINUS40CREF; + data[id].ref_adc_val[1] = PLUS30CREF; + data[id].ref_adc_val[2] = PLUS125CREF; + get_efuse_values(id, &data[id], err, bgp); + +prepare_lookup: + if (id == 0 && workaround_needed) { + prep_lookup_table(err[0], err[1], err[2], 0); + } else if (id == 0 && !workaround_needed) { + for (j = 0; j < table_size; j++) + derived_table[j] = ref_table[j]; + } + + val = readl(data[id].bgp->cfg2_base + data[id].ctrl_offset); + val |= (K3_VTM_TMPSENS_CTRL_MAXT_OUTRG_EN | + K3_VTM_TMPSENS_CTRL_SOC | + K3_VTM_TMPSENS_CTRL_CLRZ | BIT(4)); + writel(val, data[id].bgp->cfg2_base + data[id].ctrl_offset); + + bgp->ts_data[id] = &data[id]; + data[id].ti_thermal = + devm_thermal_zone_of_sensor_register(bgp->dev, id, + &data[id], + &k3_of_thermal_ops); + if (IS_ERR(data[id].ti_thermal)) { + dev_err(bgp->dev, "thermal zone device is NULL\n"); + ret = PTR_ERR(data[id].ti_thermal); + goto err_alloc; + } + + reg_cnt++; + + /* Initialize Previous temp */ + k3_thermal_get_temp(&data[id], &data[id].prev_temp); + } + + /* + * Program TSHUT thresholds + * Step 1: set the thresholds to ~123C and 105C WKUP_VTM_MISC_CTRL2 + * Step 2: WKUP_VTM_TMPSENS_CTRL_j set the MAXT_OUTRG_EN bit + * This is already taken care as per of init + * Step 3: WKUP_VTM_MISC_CTRL set the ANYMAXT_OUTRG_ALERT_EN bit + */ + high_max = k3_j72xx_bandgap_temp_to_adc_code(MAX_TEMP); + low_max = k3_j72xx_bandgap_temp_to_adc_code(COOL_DOWN_TEMP); + + writel((low_max << 16) | high_max, data[0].bgp->cfg2_base + + K3_VTM_MISC_CTRL2_OFFSET); + mdelay(100); + writel(K3_VTM_ANYMAXT_OUTRG_ALERT_EN, data[0].bgp->cfg2_base + + K3_VTM_MISC_CTRL_OFFSET); + + platform_set_drvdata(pdev, bgp); + +#ifdef DEBUG_VTM + print_look_up_table(dev); +#endif + /* + * Now that the derived_table has the appropriate look up values + * Free up the ref_table + */ + kfree(ref_table); + + return 0; + +err_alloc: + pm_runtime_put_sync(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + return ret; +} + +static int k3_j72xx_bandgap_remove(struct platform_device *pdev) +{ + pm_runtime_put_sync(&pdev->dev); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +const struct k3_j72xx_bandgap_j72xx_data k3_j72xx_bandgap_j721e_data = { + .workaround = 1, +}; + +const struct k3_j72xx_bandgap_j72xx_data k3_j72xx_bandgap_j7200_data = { + .workaround = 0, +}; + +static const struct of_device_id of_k3_j72xx_bandgap_match[] = { + { + .compatible = "ti,j721e-vtm", + .data = (void *)&k3_j72xx_bandgap_j721e_data, + }, + { + .compatible = "ti,j7200-vtm", + .data = (void *)&k3_j72xx_bandgap_j7200_data, + }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, of_k3_j72xx_bandgap_match); + +static struct platform_driver k3_j72xx_bandgap_sensor_driver = { + .probe = k3_j72xx_bandgap_probe, + .remove = k3_j72xx_bandgap_remove, + .driver = { + .name = "k3-j72xx-soc-thermal", + .of_match_table = of_k3_j72xx_bandgap_match, + }, +}; + +module_platform_driver(k3_j72xx_bandgap_sensor_driver); + +MODULE_DESCRIPTION("K3 bandgap temperature sensor driver"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("J Keerthy <j-keerthy@xxxxxx>"); -- 2.17.1
