Re: [PATCH v4] Thermal: exynos: Add sysfs node supporting exynos'semulation mode.
From: Zhang Rui
Date: Tue Nov 20 2012 - 21:00:39 EST
On Thu, 2012-11-08 at 14:54 +0530, Amit Kachhap wrote:
> Hi Jonghwa Lee,
>
> I tested this patch and it looks good. I have some minor comments below,
>
> Reviewed-by: Amit Daniel Kachhap <amit.kachhap@xxxxxxxxxx>
>
Hi, Lee,
I suppose there should be an updated version being sent out soon, right?
Thanks,
rui
> Thanks,
> Amit Daniel
> On 2 November 2012 07:54, Jonghwa Lee <jonghwa3.lee@xxxxxxxxxxx> wrote:
> > This patch supports exynos's emulation mode with newly created sysfs node.
> > Exynos 4x12 (4212, 4412) and 5 series provide emulation mode for thermal
> > management unit. Thermal emulation mode supports software debug for TMU's
> > operation. User can set temperature manually with software code and TMU
> > will read current temperature from user value not from sensor's value.
> > This patch includes also documentary placed under Documentation/thermal/.
> >
> > Signed-off-by: Jonghwa Lee <jonghwa3.lee@xxxxxxxxxxx>
> > ---
> > v4
> > - Fix Typo.
> > - Remove unnecessary codes.
> > - Add comments about feature of exynos emulation operation to the document.
> >
> > v3
> > - Remove unnecessay variables.
> > - Do some code clean in exynos_tmu_emulation_store().
> > - Make wrapping function of sysfs node creation function to use
> > #ifdefs in minimum.
> >
> > v2
> > exynos_thermal.c
> > - Fix build error occured by wrong emulation control register name.
> > - Remove exynos5410 dependent codes.
> > exynos_thermal_emulation
> > - Align indentation.
> >
> > Documentation/thermal/exynos_thermal_emulation | 56 +++++++++++++++
> > drivers/thermal/Kconfig | 9 +++
> > drivers/thermal/exynos_thermal.c | 91 ++++++++++++++++++++++++
> > 3 files changed, 156 insertions(+), 0 deletions(-)
> > create mode 100644 Documentation/thermal/exynos_thermal_emulation
> >
> > diff --git a/Documentation/thermal/exynos_thermal_emulation b/Documentation/thermal/exynos_thermal_emulation
> > new file mode 100644
> > index 0000000..a6ea06f
> > --- /dev/null
> > +++ b/Documentation/thermal/exynos_thermal_emulation
> > @@ -0,0 +1,56 @@
> > +EXYNOS EMULATION MODE
> > +========================
> > +
> > +Copyright (C) 2012 Samsung Electronics
> > +
> > +Written by Jonghwa Lee <jonghwa3.lee@xxxxxxxxxxx>
> > +
> > +Description
> > +-----------
> > +
> > +Exynos 4x12 (4212, 4412) and 5 series provide emulation mode for thermal management unit.
> > +Thermal emulation mode supports software debug for TMU's operation. User can set temperature
> > +manually with software code and TMU will read current temperature from user value not from
> > +sensor's value.
> > +
> > +Enabling CONFIG_EXYNOS_THERMAL_EMUL option will make this support in available.
> > +When it's enabled, sysfs node will be created under
> > +/sys/bus/platform/devices/'exynos device name'/ with name of 'emulation'.
> > +
> > +The sysfs node, 'emulation', will contain value 0 for the initial state. When you input any
> > +temperature you want to update to sysfs node, it automatically enable emulation mode and
> > +current temperature will be changed into it.
> > +(Exynos also supports user changable delay time which would be used to delay of
> > + changing temperature. However, this node only uses same delay of real sensing time, 938us.)
> > +
> > +Exynos emulation mode requires synchronous of value changing and enabling. It means when you
> > +want to update the any value of delay or next temperature, then you have to enable emulation
> > +mode at the same time. (Or you have to keep the mode enabling.) If you don't, it fails to
> > +change the value to updated one and just use last succeessful value repeatedly. That's why
> > +this node gives users the right to change termerpature only. Just one interface makes it more
> > +simply to use.
> > +
> > +Disabling emulation mode only requires writing value 0 to sysfs node.
> > +
> > +
> > +TEMP 120 |
> > + |
> > + 100 |
> > + |
> > + 80 |
> > + | +-----------
> > + 60 | | |
> > + | +-------------| |
> > + 40 | | | |
> > + | | | |
> > + 20 | | | +----------
> > + | | | | |
> > + 0 |______________|_____________|__________|__________|_________
> > + A A A A TIME
> > + |<----->| |<----->| |<----->| |
> > + | 938us | | | | | |
> > +emulation : 0 50 | 70 | 20 | 0
> > +current temp : sensor 50 70 20 sensor
> > +
> > +
> > +
> > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > index e1cb6bd..c02a66c 100644
> > --- a/drivers/thermal/Kconfig
> > +++ b/drivers/thermal/Kconfig
> > @@ -55,3 +55,12 @@ config EXYNOS_THERMAL
> > help
> > If you say yes here you get support for TMU (Thermal Managment
> > Unit) on SAMSUNG EXYNOS series of SoC.
> > +
> > +config EXYNOS_THERMAL_EMUL
> > + bool "EXYNOS TMU emulation mode support"
> > + depends on !CPU_EXYNOS4210 && EXYNOS_THERMAL
> Instead of using CPU_EXYNOS4210 here it is better to use data->soc ==
> SOC_ARCH_EXYNOS4210 inside the emulation show/store functions.
> > + help
> > + Exynos 4412 and 4414 and 5 series has emulation mode on TMU.
> > + Enable this option will be make sysfs node in exynos thermal platform
> > + device directory to support emulation mode. With emulation mode sysfs
> > + node, you can manually input temperature to TMU for simulation purpose.
> > diff --git a/drivers/thermal/exynos_thermal.c b/drivers/thermal/exynos_thermal.c
> > index fd03e85..eebd4e5 100644
> > --- a/drivers/thermal/exynos_thermal.c
> > +++ b/drivers/thermal/exynos_thermal.c
> > @@ -99,6 +99,14 @@
> > #define IDLE_INTERVAL 10000
> > #define MCELSIUS 1000
> >
> > +#ifdef CONFIG_EXYNOS_THERMAL_EMUL
> > +#define EXYNOS_EMUL_TIME 0x57F0
> > +#define EXYNOS_EMUL_TIME_SHIFT 16
> > +#define EXYNOS_EMUL_DATA_SHIFT 8
> > +#define EXYNOS_EMUL_DATA_MASK 0xFF
> > +#define EXYNOS_EMUL_ENABLE 0x1
> > +#endif /* CONFIG_EXYNOS_THERMAL_EMUL */
> > +
> > /* CPU Zone information */
> > #define PANIC_ZONE 4
> > #define WARN_ZONE 3
> > @@ -832,6 +840,82 @@ static inline struct exynos_tmu_platform_data *exynos_get_driver_data(
> > return (struct exynos_tmu_platform_data *)
> > platform_get_device_id(pdev)->driver_data;
> > }
> > +
> > +#ifdef CONFIG_EXYNOS_THERMAL_EMUL
> > +static ssize_t exynos_tmu_emulation_show(struct device *dev,
> > + struct device_attribute *attr,
> > + char *buf)
> > +{
> > + struct platform_device *pdev = container_of(dev,
> > + struct platform_device, dev);
> > + struct exynos_tmu_data *data = platform_get_drvdata(pdev);
> > + unsigned int reg;
> > + u8 temp_code;
> > + int temp = 0;
> > +
> > + mutex_lock(&data->lock);
> > + clk_enable(data->clk);
> > + reg = readl(data->base + EXYNOS_EMUL_CON);
> > + clk_disable(data->clk);
> > + mutex_unlock(&data->lock);
> > +
> > + if (reg & EXYNOS_EMUL_ENABLE) {
> > + reg >>= EXYNOS_EMUL_DATA_SHIFT;
> > + temp_code = reg & EXYNOS_EMUL_DATA_MASK;
> > + temp = code_to_temp(data, temp_code);
> > + }
> > +
> > + return sprintf(buf, "%d\n", temp);
> Currently in /sys/devices/virtual/thermal/thermal_zone0/ all
> temperatures are shown in millicelsius so it is better show this in
> millicelsius also.
> > +}
> > +
> > +static ssize_t exynos_tmu_emulation_store(struct device *dev,
> > + struct device_attribute *attr,
> > + const char *buf, size_t count)
> > +{
> > + struct platform_device *pdev = container_of(dev,
> > + struct platform_device, dev);
> > + struct exynos_tmu_data *data = platform_get_drvdata(pdev);
> > + unsigned int reg;
> > + int temp;
> > +
> > + if (!sscanf(buf, "%d\n", &temp) || temp < 0)
> > + return -EINVAL;
> > +
> > + mutex_lock(&data->lock);
> > + clk_enable(data->clk);
> > +
> > + reg = readl(data->base + EXYNOS_EMUL_CON);
> > +
> > + if (temp)
> > + reg = (EXYNOS_EMUL_TIME << EXYNOS_EMUL_TIME_SHIFT) |
> > + (temp_to_code(data, temp) << EXYNOS_EMUL_DATA_SHIFT) |
> Same as above.
> > + EXYNOS_EMUL_ENABLE;
> > + else
> > + reg &= ~EXYNOS_EMUL_ENABLE;
> > +
> > + writel(reg, data->base + EXYNOS_EMUL_CON);
> > +
> > + clk_disable(data->clk);
> > + mutex_unlock(&data->lock);
> > +
> > + return count;
> > +}
> > +
> > +static DEVICE_ATTR(emulation, 0644, exynos_tmu_emulation_show,
> > + exynos_tmu_emulation_store);
> > +static int create_emulation_sysfs(struct device *dev)
> > +{
> > + return device_create_file(dev, &dev_attr_emulation);
> > +}
> > +static void remove_emulation_sysfs(struct device *dev)
> > +{
> > + device_remove_file(dev, &dev_attr_emulation);
> > +}
> > +#else
> > +static inline int create_emulation_sysfs(struct device *dev) {return 0;}
> > +static inline void remove_emulation_sysfs(struct device *dev){}
> > +#endif
> > +
> > static int __devinit exynos_tmu_probe(struct platform_device *pdev)
> > {
> > struct exynos_tmu_data *data;
> > @@ -930,6 +1014,11 @@ static int __devinit exynos_tmu_probe(struct platform_device *pdev)
> > dev_err(&pdev->dev, "Failed to register thermal interface\n");
> > goto err_clk;
> > }
> > +
> > + ret = create_emulation_sysfs(&pdev->dev);
> > + if (ret)
> > + dev_err(&pdev->dev, "Failed to create emulation mode sysfs node\n");
> > +
> > return 0;
> > err_clk:
> > platform_set_drvdata(pdev, NULL);
> > @@ -941,6 +1030,8 @@ static int __devexit exynos_tmu_remove(struct platform_device *pdev)
> > {
> > struct exynos_tmu_data *data = platform_get_drvdata(pdev);
> >
> > + remove_emulation_sysfs(&pdev->dev);
> > +
> > exynos_tmu_control(pdev, false);
> >
> > exynos_unregister_thermal();
> > --
> > 1.7.4.1
> >
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