Re: [PATCH v3 1/3] thermal: sun8i: add thermal driver for h6

From: Frank Lee
Date: Fri Jun 07 2019 - 09:57:20 EST

On Fri, Jun 7, 2019 at 9:50 PM Frank Lee <tiny.windzz@xxxxxxxxx> wrote:
>
> HI OndÅej,
>
>
> On Mon, May 27, 2019 at 10:25 PM OndÅej Jirman <megous@xxxxxxxxxx> wrote:
> >
> > Hi Yangtao,
> >
> > On Sat, May 25, 2019 at 02:13:27PM -0400, Yangtao Li wrote:
> > > This patch adds the support for allwinner thermal sensor, within
> > > allwinner SoC. It will register sensors for thermal framework
> > > and use device tree to bind cooling device.
> > >
> > > Signed-off-by: Yangtao Li <tiny.windzz@xxxxxxxxx>
> > > ---
> > > MAINTAINERS | 7 +
> > > drivers/thermal/Kconfig | 14 +
> > > drivers/thermal/Makefile | 1 +
> > > drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
> > > 4 files changed, 459 insertions(+)
> > > create mode 100644 drivers/thermal/sun8i_thermal.c
> > >
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index 2336dd26ece4..d312f9eecf0d 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -674,6 +674,13 @@ L: linux-crypto@xxxxxxxxxxxxxxx
> > > S: Maintained
> > > F: drivers/crypto/sunxi-ss/
> > >
> > > +ALLWINNER THERMAL DRIVER
> > > +M: Yangtao Li <tiny.windzz@xxxxxxxxx>
> > > +L: linux-pm@xxxxxxxxxxxxxxx
> > > +S: Maintained
> > > +F: Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> > > +F: drivers/thermal/sun8i_thermal.c
> > > +
> > > ALLWINNER VPU DRIVER
> > > M: Maxime Ripard <maxime.ripard@xxxxxxxxxxx>
> > > M: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx>
> > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > > index 9966364a6deb..e5465053d66f 100644
> > > --- a/drivers/thermal/Kconfig
> > > +++ b/drivers/thermal/Kconfig
> > > @@ -262,6 +262,20 @@ config SPEAR_THERMAL
> > > Enable this to plug the SPEAr thermal sensor driver into the Linux
> > > thermal framework.
> > >
> > > +config SUN8I_THERMAL
> > > + tristate "Allwinner sun8i thermal driver"
> > > + depends on ARCH_SUNXI || COMPILE_TEST
> > > + depends on HAS_IOMEM
> > > + depends on NVMEM_SUNXI_SID
> > > + depends on OF
> > > + depends on RESET_CONTROLLER
> > > + help
> > > + Support for the sun8i thermal sensor driver into the Linux thermal
> > > + framework.
> > > +
> > > + To compile this driver as a module, choose M here: the
> > > + module will be called sun8i-thermal.
> > > +
> > > config ROCKCHIP_THERMAL
> > > tristate "Rockchip thermal driver"
> > > depends on ARCH_ROCKCHIP || COMPILE_TEST
> > > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> > > index 74a37c7f847a..fa6f8b206281 100644
> > > --- a/drivers/thermal/Makefile
> > > +++ b/drivers/thermal/Makefile
> > > @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
> > > obj-y += broadcom/
> > > obj-$(CONFIG_THERMAL_MMIO) += thermal_mmio.o
> > > obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o
> > > +obj-$(CONFIG_SUN8I_THERMAL) += sun8i_thermal.o
> > > obj-$(CONFIG_ROCKCHIP_THERMAL) += rockchip_thermal.o
> > > obj-$(CONFIG_RCAR_THERMAL) += rcar_thermal.o
> > > obj-$(CONFIG_RCAR_GEN3_THERMAL) += rcar_gen3_thermal.o
> > > diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> > > new file mode 100644
> > > index 000000000000..a9cc2197f4cb
> > > --- /dev/null
> > > +++ b/drivers/thermal/sun8i_thermal.c
> > > @@ -0,0 +1,437 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +/*
> > > + * Thermal sensor driver for Allwinner SOC
> > > + * Copyright (C) 2019 Yangtao Li
> > > + *
> > > + * Based on the work of Icenowy Zheng <icenowy@xxxxxxx>
> > > + * Based on the work of Ondrej Jirman <megous@xxxxxxxxxx>
> > > + * Based on the work of Josef Gajdusek <atx@xxxxxxxx>
> > > + */
> > > +
> > > +#include <linux/clk.h>
> > > +#include <linux/device.h>
> > > +#include <linux/interrupt.h>
> > > +#include <linux/wait.h>
> > > +#include <linux/module.h>
> > > +#include <linux/nvmem-consumer.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/regmap.h>
> > > +#include <linux/reset.h>
> > > +#include <linux/slab.h>
> > > +#include <linux/thermal.h>
> > > +
> > > +#define MAX_SENSOR_NUM 4
> > > +
> > > +#define FT_TEMP_MASK GENMASK(11, 0)
> > > +#define TEMP_CALIB_MASK GENMASK(11, 0)
> > > +#define TEMP_TO_REG 672
> > > +#define CALIBRATE_DEFAULT 0x800
> > > +
> > > +#define SUN50I_THS_CTRL0 0x00
> > > +#define SUN50I_H6_THS_ENABLE 0x04
> > > +#define SUN50I_H6_THS_PC 0x08
> > > +#define SUN50I_H6_THS_DIC 0x10
> > > +#define SUN50I_H6_THS_DIS 0x20
> > > +#define SUN50I_H6_THS_MFC 0x30
> > > +#define SUN50I_H6_THS_TEMP_CALIB 0xa0
> > > +#define SUN50I_H6_THS_TEMP_DATA 0xc0
> > > +
> > > +#define SUN50I_THS_CTRL0_T_ACQ(x) ((GENMASK(15, 0) & (x)) << 16)
> > > +#define SUN50I_THS_FILTER_EN BIT(2)
> > > +#define SUN50I_THS_FILTER_TYPE(x) (GENMASK(1, 0) & (x))
> > > +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x) ((GENMASK(19, 0) & (x)) << 12)
> > > +#define SUN50I_H6_THS_DATA_IRQ_STS(x) BIT(x)
> > > +
> > > +/* millidegree celsius */
> > > +#define SUN50I_H6_FT_DEVIATION 7000
> > > +
> > > +struct ths_device;
> > > +
> > > +struct tsensor {
> > > + struct ths_device *tmdev;
> > > + struct thermal_zone_device *tzd;
> > > + int id;
> > > + wait_queue_head_t wait_queue;
> > > +};
> > > +
> > > +struct ths_thermal_chip {
> > > + int sensor_num;
> > > + int offset;
> > > + int scale;
> > > + int ft_deviation;
> > > + int temp_calib_base;
> > > + int temp_data_base;
> > > + int (*calibrate)(struct ths_device *tmdev);
> > > + int (*init)(struct ths_device *tmdev);
> > > + irqreturn_t (*irq_thread)(int irq, void *data);
> > > +};
> > > +
> > > +struct ths_device {
> > > + const struct ths_thermal_chip *chip;
> > > + struct device *dev;
> > > + struct regmap *regmap;
> > > + struct reset_control *reset;
> > > + struct clk *bus_clk;
> > > + struct tsensor sensor[MAX_SENSOR_NUM];
> > > + int data_ready;
> > > +};
> > > +
> > > +/* Temp Unit: millidegree Celsius */
> > > +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> > > + int reg)
> > > +{
> > > + return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> > > +}
> > > +
> > > +static int sun8i_ths_get_temp(void *data, int *temp)
> > > +{
> > > + struct tsensor *s = data;
> > > + struct ths_device *tmdev = s->tmdev;
> > > + int val;
> > > +
> > > + wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> > > + tmdev->data_ready &= ~BIT(s->id);
> >
> > I've looked at thermal_core.c and it looks like that the proper way to handle
> > this situation is just returning -EAGAIN.
>
> What we are doing now is to turn it into an interrupt-based program.
> Every time we use temperature data, we need to wait until new data is collected.
>
> >
> > See update_temperature() function in thermal_core.c.
> >
> > That will suppress the warning about failure to read thermal zone. Also
> > it's much simpler than this wait_queue stuff. No other thermal driver uses this
> > either. Also get_temp is called under thermal_list_lock mutex and that would
> > block cooling device registrations and god knows what else.
>
> Since there is no valid temperature data, it cannot be blocked.

Since there is no valid temperature data, why can't it be blocked?

>
> MBR,
> Yangtao
>
> >
> > Other than that, and what Maxime said, I don't see any more issues.
> >
> > thank you,
> > o.
> >
> > > + regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> > > + 0x4 * s->id, &val);
> > > +
> > > + *temp = sun8i_ths_reg2temp(tmdev, val);
> > > + /*
> > > + * XX - According to the original sdk, there are some platforms(rarely)
> > > + * that add a fixed offset value after calculating the temperature
> > > + * value. We can't simply put it on the formula for calculating the
> > > + * temperature above, because the formula for calculating the
> > > + * temperature above is also used when the sensor is calibrated. If
> > > + * do this, the correct calibration formula is hard to know.
> > > + */
> > > + if (tmdev->chip->ft_deviation)
> > > + *temp += tmdev->chip->ft_deviation;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static const struct thermal_zone_of_device_ops ths_ops = {
> > > + .get_temp = sun8i_ths_get_temp,
> > > +};
> > > +
> > > +static const struct regmap_config config = {
> > > + .reg_bits = 32,
> > > + .val_bits = 32,
> > > + .reg_stride = 4,
> > > + .fast_io = true,
> > > +};
> > > +
> > > +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> > > +{
> > > + wait_queue_head_t *data_wait;
> > > + struct ths_device *tmdev = data;
> > > + int i, state;
> > > +
> > > + regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> > > +
> > > + for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > + data_wait = &tmdev->sensor[i].wait_queue;
> > > +
> > > + if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> > > + /* clear data irq pending */
> > > + regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> > > + SUN50I_H6_THS_DATA_IRQ_STS(i));
> > > +
> > > + tmdev->data_ready |= BIT(i);
> > > + wake_up(data_wait);
> > > + }
> > > + }
> > > +
> > > + return IRQ_HANDLED;
> > > +}
> > > +
> > > +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> > > +{
> > > + struct device *dev = tmdev->dev;
> > > + struct platform_device *pdev = to_platform_device(dev);
> > > + struct resource *mem;
> > > + void __iomem *base;
> > > + int ret, irq;
> > > +
> > > + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > + base = devm_ioremap_resource(dev, mem);
> > > + if (IS_ERR(base))
> > > + return PTR_ERR(base);
> > > +
> > > + tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> > > + if (IS_ERR(tmdev->regmap))
> > > + return PTR_ERR(tmdev->regmap);
> > > +
> > > + tmdev->reset = devm_reset_control_get(dev, 0);
> > > + if (IS_ERR(tmdev->reset))
> > > + return PTR_ERR(tmdev->reset);
> > > +
> > > + tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> > > + if (IS_ERR(tmdev->bus_clk))
> > > + return PTR_ERR(tmdev->bus_clk);
> > > +
> > > + irq = platform_get_irq(pdev, 0);
> > > + if (irq < 0)
> > > + return irq;
> > > +
> > > + ret = devm_request_threaded_irq(dev, irq, NULL,
> > > + tmdev->chip->irq_thread,
> > > + IRQF_ONESHOT, "ths", tmdev);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + ret = reset_control_deassert(tmdev->reset);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + ret = clk_prepare_enable(tmdev->bus_clk);
> > > + if (ret)
> > > + goto assert_reset;
> > > +
> > > + ret = tmdev->chip->calibrate(tmdev);
> > > + if (ret)
> > > + goto bus_disable;
> > > +
> > > + return 0;
> > > +
> > > +bus_disable:
> > > + clk_disable_unprepare(tmdev->bus_clk);
> > > +assert_reset:
> > > + reset_control_assert(tmdev->reset);
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> > > +{
> > > + struct nvmem_cell *calcell;
> > > + struct device *dev = tmdev->dev;
> > > + u16 *caldata;
> > > + size_t callen;
> > > + int ft_temp;
> > > + int i, ret = 0;
> > > +
> > > + calcell = devm_nvmem_cell_get(dev, "calib");
> > > + if (IS_ERR(calcell)) {
> > > + if (PTR_ERR(calcell) == -EPROBE_DEFER)
> > > + return -EPROBE_DEFER;
> > > + /*
> > > + * Even if the external calibration data stored in sid is
> > > + * not accessible, the THS hardware can still work, although
> > > + * the data won't be so accurate.
> > > + *
> > > + * The default value of calibration register is 0x800 for
> > > + * every sensor, and the calibration value is usually 0x7xx
> > > + * or 0x8xx, so they won't be away from the default value
> > > + * for a lot.
> > > + *
> > > + * So here we do not return error if the calibartion data is
> > > + * not available, except the probe needs deferring.
> > > + */
> > > + goto out;
> > > + }
> > > +
> > > + caldata = nvmem_cell_read(calcell, &callen);
> > > + if (IS_ERR(caldata)) {
> > > + ret = PTR_ERR(caldata);
> > > + goto out;
> > > + }
> > > +
> > > + if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> > > + ret = -EINVAL;
> > > + goto out_free;
> > > + }
> > > +
> > > + /*
> > > + * efuse layout:
> > > + *
> > > + * 0 11 16 32
> > > + * +-------+-------+-------+
> > > + * |temp| |sensor0|sensor1|
> > > + * +-------+-------+-------+
> > > + *
> > > + * The calibration data on the H6 is the ambient temperature and
> > > + * sensor values that are filled during the factory test stage.
> > > + *
> > > + * The unit of stored FT temperature is 0.1 degreee celusis.
> > > + * Through the stored ambient temperature and the data read
> > > + * by the sensor, after a certain calculation, the calibration
> > > + * value to be compensated can be obtained.
> > > + */
> > > + ft_temp = caldata[0] & FT_TEMP_MASK;
> > > +
> > > + for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > + int reg = (int)caldata[i + 1];
> > > + int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> > > + int delta, cdata, calib_offest;
> > > +
> > > + /*
> > > + * To calculate the calibration value:
> > > + *
> > > + * X(in Celsius) = Ts - ft_temp
> > > + * delta = X * 10000 / TEMP_TO_REG
> > > + * cdata = CALIBRATE_DEFAULT - delta
> > > + *
> > > + * cdata: calibration value
> > > + */
> > > + delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> > > + cdata = CALIBRATE_DEFAULT - delta;
> > > + if (cdata & ~TEMP_CALIB_MASK) {
> > > + /*
> > > + * Calibration value more than 12-bit, but calibration
> > > + * register is 12-bit. In this case, ths hardware can
> > > + * still work without calibration, although the data
> > > + * won't be so accurate.
> > > + */
> > > + dev_warn(dev, "sensor%d is not calibrated.\n", i);
> > > +
> > > + continue;
> > > + }
> > > +
> > > + calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> > > +
> > > + if (i % 2) {
> > > + int val;
> > > +
> > > + regmap_read(tmdev->regmap, calib_offest, &val);
> > > + val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> > > + regmap_write(tmdev->regmap, calib_offest, val);
> > > + } else {
> > > + regmap_write(tmdev->regmap, calib_offest, cdata);
> > > + }
> > > + }
> > > +
> > > +out_free:
> > > + kfree(caldata);
> > > +out:
> > > + return ret;
> > > +}
> > > +
> > > +static int sun8i_ths_register(struct ths_device *tmdev)
> > > +{
> > > + struct thermal_zone_device *tzd;
> > > + int i;
> > > +
> > > + for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > + tmdev->sensor[i].tmdev = tmdev;
> > > + tmdev->sensor[i].id = i;
> > > + tmdev->sensor[i].tzd =
> > > + devm_thermal_zone_of_sensor_register(tmdev->dev,
> > > + i,
> > > + &tmdev->sensor[i],
> > > + &ths_ops);
> > > + if (IS_ERR(tmdev->sensor[i].tzd))
> > > + return PTR_ERR(tzd);
> > > + }
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int sun8i_ths_probe(struct platform_device *pdev)
> > > +{
> > > + struct ths_device *tmdev;
> > > + struct device *dev = &pdev->dev;
> > > + int i, ret;
> > > +
> > > + tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> > > + if (!tmdev)
> > > + return -ENOMEM;
> > > +
> > > + tmdev->dev = dev;
> > > + tmdev->chip = of_device_get_match_data(&pdev->dev);
> > > + if (!tmdev->chip)
> > > + return -EINVAL;
> > > +
> > > + /*
> > > + * Initialize wait_queue in advance, to avoid calling wake_up
> > > + * before ths is registered in isr.
> > > + */
> > > + for (i = 0; i < tmdev->chip->sensor_num; i++)
> > > + init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> > > +
> > > + platform_set_drvdata(pdev, tmdev);
> > > +
> > > + ret = sun8i_ths_resource_init(tmdev);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + ret = tmdev->chip->init(tmdev);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + ret = sun8i_ths_register(tmdev);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static int sun8i_ths_remove(struct platform_device *pdev)
> > > +{
> > > + struct ths_device *tmdev = platform_get_drvdata(pdev);
> > > +
> > > + clk_disable_unprepare(tmdev->bus_clk);
> > > + reset_control_assert(tmdev->reset);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int sun50i_thermal_init(struct ths_device *tmdev)
> > > +{
> > > + int val;
> > > +
> > > + /*
> > > + * clkin = 24MHz
> > > + * T acquire = clkin / (x + 1)
> > > + * = 20us
> > > + */
> > > + regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
> > > + SUN50I_THS_CTRL0_T_ACQ(479));
> > > + /* average over 4 samples */
> > > + regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
> > > + SUN50I_THS_FILTER_EN |
> > > + SUN50I_THS_FILTER_TYPE(1));
> > > + /* period = (x + 1) * 4096 / clkin; ~10ms */
> > > + regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
> > > + SUN50I_H6_THS_PC_TEMP_PERIOD(58));
> > > + /* enable sensor */
> > > + val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > > + regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
> > > + /* thermal data interrupt enable */
> > > + val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > > + regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static const struct ths_thermal_chip sun50i_h6_ths = {
> > > + .sensor_num = 2,
> > > + .offset = -2794,
> > > + .scale = -67,
> > > + .ft_deviation = SUN50I_H6_FT_DEVIATION,
> > > + .temp_calib_base = SUN50I_H6_THS_TEMP_CALIB,
> > > + .temp_data_base = SUN50I_H6_THS_TEMP_DATA,
> > > + .calibrate = sun50i_ths_calibrate,
> > > + .init = sun50i_thermal_init,
> > > + .irq_thread = sun50i_h6_irq_thread,
> > > +};
> > > +
> > > +static const struct of_device_id of_ths_match[] = {
> > > + { .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
> > > + { /* sentinel */ },
> > > +};
> > > +MODULE_DEVICE_TABLE(of, of_ths_match);
> > > +
> > > +static struct platform_driver ths_driver = {
> > > + .probe = sun8i_ths_probe,
> > > + .remove = sun8i_ths_remove,
> > > + .driver = {
> > > + .name = "sun8i-thermal",
> > > + .of_match_table = of_ths_match,
> > > + },
> > > +};
> > > +module_platform_driver(ths_driver);
> > > +
> > > +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
> > > +MODULE_LICENSE("GPL v2");
> > > --
> > > 2.17.0
> > >
> > >
> > > _______________________________________________
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> > > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
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