On Wed, Dec 11, 2024 at 04:46:22PM +0100, Marco Felsch wrote:
> On 24-12-10, Frank Li wrote:
> > From: Pengfei Li <pengfei.li_1@xxxxxxx>
> >
> > Introduce support for the i.MX91 thermal monitoring unit, which features a
> > single sensor for the CPU. The register layout differs from other chips,
> > necessitating the creation of a dedicated file for this.
> >
> > Signed-off-by: Pengfei Li <pengfei.li_1@xxxxxxx>
> > Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> > Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> > ---
> > change from v1 to v2
> > - use low case for hexvalue
> > - combine struct imx91_tmu and tmu_sensor
> > - simplify imx91_tmu_start() and imx91_tmu_enable()
> > - use s16 for imx91_tmu_get_temp(), which may negative value
> > - use reverse christmas tree style
> > - use run time pm
> > - use oneshot to sample temp
> > - register thermal zone after hardware init
> > ---
> > drivers/thermal/Kconfig | 10 ++
> > drivers/thermal/Makefile | 1 +
> > drivers/thermal/imx91_thermal.c | 265 ++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 276 insertions(+)
> >
> > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > index d3f9686e26e71..da403ed86aeb1 100644
> > --- a/drivers/thermal/Kconfig
> > +++ b/drivers/thermal/Kconfig
> > @@ -296,6 +296,16 @@ config IMX8MM_THERMAL
> > cpufreq is used as the cooling device to throttle CPUs when the passive
> > trip is crossed.
> >
> > +config IMX91_THERMAL
> > + tristate "Temperature sensor driver for NXP i.MX91 SoC"
> > + depends on ARCH_MXC || COMPILE_TEST
> > + depends on OF
> > + help
> > + Support for Temperature sensor found on NXP i.MX91 SoC.
> > + It supports one critical trip point and one passive trip point. The
> > + 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
> > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> > index 9abf43a74f2bb..08da241e6a598 100644
> > --- a/drivers/thermal/Makefile
> > +++ b/drivers/thermal/Makefile
> > @@ -50,6 +50,7 @@ obj-$(CONFIG_ARMADA_THERMAL) += armada_thermal.o
> > obj-$(CONFIG_IMX_THERMAL) += imx_thermal.o
> > obj-$(CONFIG_IMX_SC_THERMAL) += imx_sc_thermal.o
> > obj-$(CONFIG_IMX8MM_THERMAL) += imx8mm_thermal.o
> > +obj-$(CONFIG_IMX91_THERMAL) += imx91_thermal.o
> > obj-$(CONFIG_MAX77620_THERMAL) += max77620_thermal.o
> > obj-$(CONFIG_QORIQ_THERMAL) += qoriq_thermal.o
> > obj-$(CONFIG_DA9062_THERMAL) += da9062-thermal.o
> > diff --git a/drivers/thermal/imx91_thermal.c b/drivers/thermal/imx91_thermal.c
> > new file mode 100644
> > index 0000000000000..ebb59eda92951
> > --- /dev/null
> > +++ b/drivers/thermal/imx91_thermal.c
> > @@ -0,0 +1,265 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright 2024 NXP.
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/clk.h>
> > +#include <linux/err.h>
> > +#include <linux/iopoll.h>
> > +#include <linux/nvmem-consumer.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/thermal.h>
> > +
> > +#define CTRL0 0x0
>
> Unused
>
> > +
> > +#define STAT0 0x10
> > +#define STAT0_DRDY0_IF_MASK BIT(16)
> > +
> > +#define DATA0 0x20
> > +
> > +#define THR_CTRL01 0x30
> > +#define THR_CTRL23 0x40
>
> Both are unused too
>
> > +#define CTRL1 0x200
>
> Unused
>
> > +#define CTRL1_SET 0x204
> > +#define CTRL1_CLR 0x208
> > +#define CTRL1_EN BIT(31)
> > +#define CTRL1_START BIT(30)
> > +#define CTRL1_STOP BIT(29)
> > +#define CTRL1_RES_MASK GENMASK(19, 18)
> > +#define CTRL1_MEAS_MODE_MASK GENMASK(25, 24)
> > +#define CTRL1_MEAS_MODE_SINGLE 0
> > +#define CTRL1_MEAS_MODE_CONTINUES 1
> > +#define CTRL1_MEAS_MODE_PERIODIC 2
> > +
> > +#define REF_DIV 0x280
> > +#define DIV_EN BIT(31)
> > +#define DIV_MASK GENMASK(23, 16)
> > +
> > +#define PUD_ST_CTRL 0x2B0
> > +#define PUDL_MASK GENMASK(23, 16)
> > +
> > +#define TRIM1 0x2E0
> > +#define TRIM2 0x2F0
> ^
> still upper-case
>
> > +#define TMU_TEMP_LOW_LIMIT -40000
> > +#define TMU_TEMP_HIGH_LIMIT 125000
> > +
> > +#define DEFAULT_TRIM1_CONFIG 0xb561bc2d
> > +#define DEFAULT_TRIM2_CONFIG 0x65d4
> > +
> > +struct imx91_tmu {
> > + void __iomem *base;
> > + struct clk *clk;
> > + struct device *dev;
> > + struct thermal_zone_device *tzd;
> > +};
> > +
> > +static void imx91_tmu_start(struct imx91_tmu *tmu, bool start)
> > +{
> > + u32 val = start ? CTRL1_START : CTRL1_STOP;
> > +
> > + writel_relaxed(val, tmu->base + CTRL1_SET);
> > +}
> > +
> > +static void imx91_tmu_enable(struct imx91_tmu *tmu, bool enable)
> > +{
> > + u32 reg = enable ? CTRL1_SET : CTRL1_CLR;
> > +
> > + writel_relaxed(CTRL1_EN, tmu->base + reg);
> > +}
> > +
> > +static int imx91_tmu_get_temp(struct thermal_zone_device *tz, int *temp)
> > +{
> > + struct imx91_tmu *tmu = thermal_zone_device_priv(tz);
> > + s16 data;
> > + int ret;
> > + u32 val;
> > +
> > + ret = pm_runtime_resume_and_get(tmu->dev);
> > + if (ret < 0)
> > + return ret;
> > +
> > + ret = readl_relaxed_poll_timeout(tmu->base + STAT0, val,
> > + val & STAT0_DRDY0_IF_MASK, 1000,
> > + 40000);
> > + if (ret)
> > + return -EAGAIN;
> ^
> Missing pm_runtime_put(). Instead goto out;
>
> > +
> > + /* DATA0 is 16bit signed number */
> > + data = readw_relaxed(tmu->base + DATA0);
> > + *temp = data * 1000 / 64;
> > + if (*temp < TMU_TEMP_LOW_LIMIT || *temp > TMU_TEMP_HIGH_LIMIT)
> > + return -EAGAIN;
> ^
> ret = -EAGAIN;
> goto out;
>
> out:
> > +
> > + pm_runtime_put(tmu->dev);
> > +
> > + return 0;
>
> return ret;
> > +}
> > +
> > +static struct thermal_zone_device_ops tmu_tz_ops = {
> > + .get_temp = imx91_tmu_get_temp,
> > +};
> > +
> > +static int imx91_init_from_nvmem_cells(struct imx91_tmu *tmu)
> > +{
> > + struct device *dev = tmu->dev;
> > + u32 trim1, trim2;
> > + int ret;
> > +
> > + ret = nvmem_cell_read_u32(dev, "trim1", &trim1);
> > + if (ret)
> > + return ret;
> > +
> > + ret = nvmem_cell_read_u32(dev, "trim2", &trim2);
> > + if (ret)
> > + return ret;
> > +
> > + if (trim1 == 0 || trim2 == 0)
> > + return -EINVAL;
> > +
> > + writel_relaxed(trim1, tmu->base + TRIM1);
> > + writel_relaxed(trim2, tmu->base + TRIM2);
> > +
> > + return 0;
> > +}
> > +
> > +static int imx91_tmu_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
>
> Since you already have the dev pointer, you can make use of it...
>
> > + struct imx91_tmu *tmu;
> > + unsigned long rate;
> > + u32 div;
> > + int ret;
> > +
> > + tmu = devm_kzalloc(&pdev->dev, sizeof(struct imx91_tmu), GFP_KERNEL);
> ^
> here
> > + if (!tmu)
> > + return -ENOMEM;
> > +
> > + tmu->dev = &pdev->dev;
>
> and here
>
> > +
> > + tmu->base = devm_platform_ioremap_resource(pdev, 0);
> > + if (IS_ERR(tmu->base))
> > + return PTR_ERR(tmu->base);
> ^
> dev_err_probe();
>
> > +
> > + tmu->clk = devm_clk_get_enabled(dev, NULL);
> > + if (IS_ERR(tmu->clk))
> > + return dev_err_probe(dev, PTR_ERR(tmu->clk), "failed to get tmu clock\n");
> > +
> > + platform_set_drvdata(pdev, tmu);
> > +
> > + /* disable the monitor during initialization */
> > + imx91_tmu_enable(tmu, false);
> > + imx91_tmu_start(tmu, false);
>
> No need to disable it here since both bits (ENABLE and START) are 0
> after a reset.
Maybe uboot enable it. We can't depend on reset value without really set
hardware reset bit.
>
> > + ret = imx91_init_from_nvmem_cells(tmu);
> > + if (ret) {
> > + writel_relaxed(DEFAULT_TRIM1_CONFIG, tmu->base + TRIM1);
> > + writel_relaxed(DEFAULT_TRIM2_CONFIG, tmu->base + TRIM2);
> ^
> Can you please anwer if _relaxed API is sufficient? I don't know why you
> making use of the _relaxed API here anyway. We have only a few MMIO
> accesses here, so why can't we use the writel() instead? This applies to
> the whole driver.
There are not big difference writel_relaxed() or writel() for this driver.
Just original owner pick one.
>
> > + }
> > +
> > + /* The typical conv clk is 4MHz, the output freq is 'rate / (div + 1)' */
> > + rate = clk_get_rate(tmu->clk);
> > + div = (rate / 4000000) - 1;
> > + if (div > FIELD_GET(DIV_MASK, DIV_MASK))
> ^
> This misuse the FIELD_GET() API. Instead please add a define e.g. DIV_MAX.
I don't think so, It avoid define another macro DIV_MAX, which may miss
defined, the related marco should come from one source.
For example:
DIV_MASK is GENMASK(23, 16), DIV_MAX is 256. But if hardware upgrade,
DIV_MASK to GENMASK(24, 16), DIV_MAX is quite easy to forget update it and
hard to find such mis-match when div value < 256.
>
> > + return -EINVAL;
> ^
> dev_err_probe()
> > +
> > + /* Set divider value and enable divider */
> > + writel_relaxed(DIV_EN | FIELD_PREP(DIV_MASK, div), tmu->base + REF_DIV);
> > +
> > + /* Set max power up delay: 'Tpud(ms) = 0xFF * 1000 / 4000000' */
> > + writel_relaxed(FIELD_PREP(PUDL_MASK, 100U), tmu->base + PUD_ST_CTRL);
> ^
> You dont need to repeat the default value, so this line can be dropped.
>
> > +
> > + /*
> > + * Set resolution mode
> > + * 00b - Conversion time = 0.59325 ms
> > + * 01b - Conversion time = 1.10525 ms
> > + * 10b - Conversion time = 2.12925 ms
> > + * 11b - Conversion time = 4.17725 ms
> > + */
> > + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x3), tmu->base + CTRL1_CLR);
> > + writel_relaxed(FIELD_PREP(CTRL1_RES_MASK, 0x1), tmu->base + CTRL1_SET);
>
> Same here, you repeat the module default after reset, so please drop it.
>
> > + writel_relaxed(CTRL1_MEAS_MODE_MASK, tmu->base + CTRL1_CLR);
> > + writel_relaxed(FIELD_PREP(CTRL1_MEAS_MODE_MASK, CTRL1_MEAS_MODE_SINGLE),
> > + tmu->base + CTRL1_SET);
> > +
> > + clk_disable_unprepare(tmu->clk);
>
> Drop this, and
>
> > + pm_runtime_set_suspended(dev);
>
> replace this with: pm_runtime_set_active();
No big difference, if set_active, we need add Enable TMU here. I can
change to set_active.
Frank
>
> > + pm_runtime_enable(dev);
> ^
> devm_pm_runtime_enable()
>
> > + tmu->tzd = devm_thermal_of_zone_register(dev, 0, tmu, &tmu_tz_ops);
> > + if (IS_ERR(tmu->tzd))
> > + return dev_err_probe(dev, PTR_ERR(tmu->tzd),
> > + "failed to register thermal zone sensor\n");
>
>
> pm_runtime_put()
>
>
> > +
> > + return 0;
> > +}
> > +
> > +static void imx91_tmu_remove(struct platform_device *pdev)
> > +{
> > + struct imx91_tmu *tmu = platform_get_drvdata(pdev);
> > +
> > + /* disable tmu */
> > + imx91_tmu_start(tmu, false);
>
> No need to clear the START bit since we are running in
> single-shot-measurements now.
>
> > + imx91_tmu_enable(tmu, false);
> > +}
> > +
> > +static int imx91_tmu_runtime_suspend(struct device *dev)
> > +{
> > + struct imx91_tmu *tmu = dev_get_drvdata(dev);
> > +
> > + /* disable tmu */
> > + imx91_tmu_start(tmu, false);
>
> Can be dropped.
>
> > + imx91_tmu_enable(tmu, false);
> > +
> > + clk_disable_unprepare(tmu->clk);
> > +
> > + return 0;
> > +}
> > +
> > +static int imx91_tmu_runtime_resume(struct device *dev)
> > +{
> > + struct imx91_tmu *tmu = dev_get_drvdata(dev);
> > + int ret;
> > +
> > + ret = clk_prepare_enable(tmu->clk);
> > + if (ret)
> > + return ret;
> > +
> > + imx91_tmu_enable(tmu, true);
> > + imx91_tmu_start(tmu, true);
>
> Drop imx91_tmu_start() from the resume since this isn't related to the
> runtime-pm. Instead the function needs to be called within
> imx91_tmu_get_temp().
>
> > + return 0;
> > +}
> > +
> > +static const struct dev_pm_ops imx91_tmu_pm_ops = {
> > + SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
> > + RUNTIME_PM_OPS(imx91_tmu_runtime_suspend, imx91_tmu_runtime_resume, NULL)
> > +};
>
> DEFINE_RUNTIME_DEV_PM_OPS()
>
> > +
> > +static const struct of_device_id imx91_tmu_table[] = {
> > + { .compatible = "fsl,imx91-tmu", },
> > + { },
> > +};
> > +MODULE_DEVICE_TABLE(of, imx91_tmu_table);
> > +
> > +static struct platform_driver imx91_tmu = {
> > + .driver = {
> > + .name = "i.MX91_thermal",
> ^
> Please don't use such names, instead use imx91_thermal.
>
> Regards,
> Marco
>
> > + .pm = pm_ptr(&imx91_tmu_pm_ops),
> > + .of_match_table = imx91_tmu_table,
> > + },
> > + .probe = imx91_tmu_probe,
> > + .remove = imx91_tmu_remove,
> > +};
> > +module_platform_driver(imx91_tmu);
> > +
> > +MODULE_AUTHOR("Peng Fan <peng.fan@xxxxxxx>");
> > +MODULE_DESCRIPTION("i.MX91 Thermal Monitor Unit driver");
> > +MODULE_LICENSE("GPL");
> >
> > --
> > 2.34.1
> >
> >
