On 18/03/2020 09:30, Keerthy wrote: > The bandgap 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 and creating work to periodically > read temperatures from the zones are supported. > There are no active/passive cooling agent supported. > > Signed-off-by: Keerthy <j-keerthy@xxxxxx> > --- > > Changes in v4: > > * Fixed comments from Daniel to remove trend function. > * Mostly cleaned up all the unused variables. > * Driver from bool to tristate. > > drivers/thermal/Kconfig | 11 ++ > drivers/thermal/Makefile | 1 + > drivers/thermal/k3_bandgap.c | 287 +++++++++++++++++++++++++++++++++++ > 3 files changed, 299 insertions(+) > create mode 100644 drivers/thermal/k3_bandgap.c > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig > index 5a05db5438d6..d848d9a3c4f1 100644 > --- a/drivers/thermal/Kconfig > +++ b/drivers/thermal/Kconfig > @@ -251,6 +251,17 @@ config IMX_THERMAL > cpufreq is used as the cooling device to throttle CPUs when the > passive trip is crossed. > > +config K3_THERMAL > + tristate "Texas Instruments K3 thermal support" > + depends on ARCH_K3 || COMPILE_TEST > + help > + If you say yes here you get thermal support for the Texas Instruments > + K3 SoC family. The current chip supported is: > + - AM654 > + > + This includes temperature reading functionality and also trend > + computation. trend is now removed :) > config MAX77620_THERMAL > tristate "Temperature sensor driver for Maxim MAX77620 PMIC" > depends on MFD_MAX77620 > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile > index 9fb88e26fb10..5ad6535139ae 100644 > --- a/drivers/thermal/Makefile > +++ b/drivers/thermal/Makefile > @@ -28,6 +28,7 @@ thermal_sys-$(CONFIG_CLOCK_THERMAL) += clock_cooling.o > # devfreq cooling > thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o > > +obj-$(CONFIG_K3_THERMAL) += k3_bandgap.o > # platform thermal drivers > obj-y += broadcom/ > obj-$(CONFIG_THERMAL_MMIO) += thermal_mmio.o > diff --git a/drivers/thermal/k3_bandgap.c b/drivers/thermal/k3_bandgap.c > new file mode 100644 > index 000000000000..d16e60335721 > --- /dev/null > +++ b/drivers/thermal/k3_bandgap.c > @@ -0,0 +1,287 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * TI Bandgap temperature sensor driver for K3 SoC Family > + * > + * Copyright (C) 2020 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/workqueue.h> Please check all the headers are needed, AFAICT workqueue.h and spinlock.h are not. > +#include <linux/thermal.h> > +#include <linux/of.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 0x80 > +#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_ADC_BEGIN_VAL 540 > +#define K3_VTM_ADC_END_VAL 944 > + > +static const int k3_adc_to_temp[] = { > + -40000, -40000, -40000, -40000, -39800, -39400, -39000, -38600, -38200, > + -37800, -37400, -37000, -36600, -36200, -35800, -35300, -34700, -34200, > + -33800, -33400, -33000, -32600, -32200, -31800, -31400, -31000, -30600, > + -30200, -29800, -29400, -29000, -28600, -28200, -27700, -27100, -26600, > + -26200, -25800, -25400, -25000, -24600, -24200, -23800, -23400, -23000, > + -22600, -22200, -21800, -21400, -21000, -20500, -19900, -19400, -19000, > + -18600, -18200, -17800, -17400, -17000, -16600, -16200, -15800, -15400, > + -15000, -14600, -14200, -13800, -13400, -13000, -12500, -11900, -11400, > + -11000, -10600, -10200, -9800, -9400, -9000, -8600, -8200, -7800, -7400, > + -7000, -6600, -6200, -5800, -5400, -5000, -4500, -3900, -3400, -3000, > + -2600, -2200, -1800, -1400, -1000, -600, -200, 200, 600, 1000, 1400, > + 1800, 2200, 2600, 3000, 3400, 3900, 4500, 5000, 5400, 5800, 6200, 6600, > + 7000, 7400, 7800, 8200, 8600, 9000, 9400, 9800, 10200, 10600, 11000, > + 11400, 11800, 12200, 12700, 13300, 13800, 14200, 14600, 15000, 15400, > + 15800, 16200, 16600, 17000, 17400, 17800, 18200, 18600, 19000, 19400, > + 19800, 20200, 20600, 21000, 21400, 21900, 22500, 23000, 23400, 23800, > + 24200, 24600, 25000, 25400, 25800, 26200, 26600, 27000, 27400, 27800, > + 28200, 28600, 29000, 29400, 29800, 30200, 30600, 31000, 31400, 31900, > + 32500, 33000, 33400, 33800, 34200, 34600, 35000, 35400, 35800, 36200, > + 36600, 37000, 37400, 37800, 38200, 38600, 39000, 39400, 39800, 40200, > + 40600, 41000, 41400, 41800, 42200, 42600, 43100, 43700, 44200, 44600, > + 45000, 45400, 45800, 46200, 46600, 47000, 47400, 47800, 48200, 48600, > + 49000, 49400, 49800, 50200, 50600, 51000, 51400, 51800, 52200, 52600, > + 53000, 53400, 53800, 54200, 54600, 55000, 55400, 55900, 56500, 57000, > + 57400, 57800, 58200, 58600, 59000, 59400, 59800, 60200, 60600, 61000, > + 61400, 61800, 62200, 62600, 63000, 63400, 63800, 64200, 64600, 65000, > + 65400, 65800, 66200, 66600, 67000, 67400, 67800, 68200, 68600, 69000, > + 69400, 69800, 70200, 70600, 71000, 71500, 72100, 72600, 73000, 73400, > + 73800, 74200, 74600, 75000, 75400, 75800, 76200, 76600, 77000, 77400, > + 77800, 78200, 78600, 79000, 79400, 79800, 80200, 80600, 81000, 81400, > + 81800, 82200, 82600, 83000, 83400, 83800, 84200, 84600, 85000, 85400, > + 85800, 86200, 86600, 87000, 87400, 87800, 88200, 88600, 89000, 89400, > + 89800, 90200, 90600, 91000, 91400, 91800, 92200, 92600, 93000, 93400, > + 93800, 94200, 94600, 95000, 95400, 95800, 96200, 96600, 97000, 97500, > + 98100, 98600, 99000, 99400, 99800, 100200, 100600, 101000, 101400, > + 101800, 102200, 102600, 103000, 103400, 103800, 104200, 104600, 105000, > + 105400, 105800, 106200, 106600, 107000, 107400, 107800, 108200, 108600, > + 109000, 109400, 109800, 110200, 110600, 111000, 111400, 111800, 112200, > + 112600, 113000, 113400, 113800, 114200, 114600, 115000, 115400, 115800, > + 116200, 116600, 117000, 117400, 117800, 118200, 118600, 119000, 119400, > + 119800, 120200, 120600, 121000, 121400, 121800, 122200, 122600, 123000, > + 123400, 123800, 124200, 124600, 124900, 125000, > +}; Can be this array replaced by an initialization array with a formula? Why do we have most of the time a step of 400 then suddenly 500 and 400 again? eg. 30600, 31000, 31400, 31900, 32500, 33000, 33400 > +struct k3_thermal_data; forward declaration not needed. > +struct k3_bandgap { > + void __iomem *base; > + const struct k3_bandgap_data *conf; > +}; > + > +/* common data structures */ > +struct k3_thermal_data { > + struct thermal_zone_device *ti_thermal; > + struct k3_bandgap *bgp; > + struct work_struct thermal_wq; > + int sensor_id; > + u32 ctrl_offset; > + u32 stat_offset; > + int prev_temp; prev_temp is assigned but not used. > +}; > + > +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 int k3_bgp_read_temp(struct k3_thermal_data *devdata, > + int *temp) > +{ > + struct k3_bandgap *bgp; > + unsigned int dtemp, s0, s1, s2; > + > + bgp = devdata->bgp; > + > + /* > + * Errata is applicable for am654 pg 1.0 silicon. There > + * is a variation of the order for 8-10 degree centigrade. > + * 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 < K3_VTM_ADC_BEGIN_VAL || dtemp > K3_VTM_ADC_END_VAL) > + return -EINVAL; > + > + *temp = k3_adc_to_temp[dtemp - K3_VTM_ADC_BEGIN_VAL]; To be sure there is not a subtle memory corruption, I would recommend to check the consistency between K3_VTM_ADC_END_VAL - K3_VTM_ADC_BEGIN_VAL and the array size at init time. For example: if (ARRAY_SIZE(k3_adc_to_temp) != (K3_VTM_ADC_END_VAL - K3_VTM_ADC_BEGIN_VAL)) > + return 0; > +} > + > +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 void k3_thermal_work(struct work_struct *work) > +{ > + struct k3_thermal_data *data = container_of(work, > + struct k3_thermal_data, thermal_wq); > + > + thermal_zone_device_update(data->ti_thermal, THERMAL_EVENT_UNSPECIFIED); > + > + dev_dbg(&data->ti_thermal->device, "updated thermal zone %s\n", > + data->ti_thermal->type); > +} > + > +static const struct of_device_id of_k3_bandgap_match[]; > + > +static int k3_bandgap_probe(struct platform_device *pdev) > +{ > + int ret = 0, cnt, val, id, reg_cnt = 0; > + struct resource *res; > + struct device *dev = &pdev->dev; > + struct k3_bandgap *bgp; > + struct k3_thermal_data *data; > + > + bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL); > + if (!bgp) > + return -ENOMEM; > + > + 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); > + > + 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); > + > + data = devm_kcalloc(dev, cnt, sizeof(*data), GFP_KERNEL); > + if (!data) { > + ret = -ENOMEM; > + goto err_alloc; > + } > + > + /* 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 * K3_VTM_REGS_PER_TS; > + data[id].stat_offset = data[id].ctrl_offset + 0x8; > + INIT_WORK(&data[id].thermal_wq, k3_thermal_work); What is supposed to do ? > + val = readl(data[id].bgp->base + data[id].ctrl_offset); > + val |= (K3_VTM_TMPSENS_CTRL_SOC | > + K3_VTM_TMPSENS_CTRL_CLRZ | > + K3_VTM_TMPSENS_CTRL_CLKON_REQ); > + val &= ~K3_VTM_TMPSENS_CTRL_CBIASSEL; > + writel(val, data[id].bgp->base + data[id].ctrl_offset); > + > + data[id].ti_thermal = > + devm_thermal_zone_of_sensor_register(dev, id, > + &data[id], > + &k3_of_thermal_ops); > + if (IS_ERR(data[id].ti_thermal)) { > + dev_err(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); > + } > + > + platform_set_drvdata(pdev, bgp); > + > + return 0; > + > +err_alloc: > + pm_runtime_put_sync(&pdev->dev); > + pm_runtime_disable(&pdev->dev); > + > + return ret; > +} > + > +static int k3_bandgap_remove(struct platform_device *pdev) > +{ > + pm_runtime_put_sync(&pdev->dev); > + pm_runtime_disable(&pdev->dev); > + > + return 0; > +} > + > +static const struct of_device_id of_k3_bandgap_match[] = { > + { > + .compatible = "ti,am654-vtm", > + }, > + { /* sentinel */ }, > +}; > +MODULE_DEVICE_TABLE(of, of_k3_bandgap_match); > + > +static struct platform_driver k3_bandgap_sensor_driver = { > + .probe = k3_bandgap_probe, > + .remove = k3_bandgap_remove, > + .driver = { > + .name = "k3-soc-thermal", > + .of_match_table = of_k3_bandgap_match, > + }, > +}; > + > +module_platform_driver(k3_bandgap_sensor_driver); > + > +MODULE_DESCRIPTION("K3 bandgap temperature sensor driver"); > +MODULE_LICENSE("GPL v2"); > +MODULE_AUTHOR("J Keerthy <j-keerthy@xxxxxx>"); > -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog
