Re: [PATCH V4 22/30] thermal: exynos: Add support for exynos5440 TMU sensor.

[amit daniel kachhap]

Hi,
On Wed, Jun 5, 2013 at 6:23 PM, Eduardo Valentin
<eduardo.valentin@xxxxxx> wrote:
> On 04-06-2013 23:20, amit daniel kachhap wrote:
>> Hi Eduardo,
>>
>> On Tue, Jun 4, 2013 at 6:25 PM, Eduardo Valentin
>> <eduardo.valentin@xxxxxx> wrote:
>>> On 04-06-2013 00:44, amit daniel kachhap wrote:
>>>> Hi Jonghwa,
>>>>
>>>> Sorry for the late reply as I was on leave.
>>>>
>>>> On Sat, May 18, 2013 at 10:53 AM,  <jonghwa3.lee@xxxxxxxxxxx> wrote:
>>>>> On 2013ë 05ì 14ì 18:58, Amit Daniel Kachhap wrote:
>>>>>
>>>>>> This patch modifies TMU controller to add changes needed to work with
>>>>>> exynos5440 platform. This sensor registers 3 instance of the tmu controller
>>>>>> with the thermal zone and hence reports 3 temperature output. This controller
>>>>>> supports upto five trip points. For critical threshold the driver uses the
>>>>>> core driver thermal framework for shutdown.
>>>>>>
>>>>>> Acked-by: Kukjin Kim <kgene.kim@xxxxxxxxxxx>
>>>>>> Signed-off-by: Amit Daniel Kachhap <amit.daniel@xxxxxxxxxxx>
>>>>>> ---
>>>>>>  .../devicetree/bindings/thermal/exynos-thermal.txt |   28 ++++++++++++-
>>>>>>  drivers/thermal/samsung/exynos_tmu.c               |   43 +++++++++++++++++--
>>>>>>  drivers/thermal/samsung/exynos_tmu.h               |    6 +++
>>>>>>  drivers/thermal/samsung/exynos_tmu_data.h          |    2 +
>>>>>>  4 files changed, 72 insertions(+), 7 deletions(-)
>>>>>>
>>>>>> diff --git a/Documentation/devicetree/bindings/thermal/exynos-thermal.txt b/Documentation/devicetree/bindings/thermal/exynos-thermal.txt
>>>>>> index 535fd0e..970eeba 100644
>>>>>> --- a/Documentation/devicetree/bindings/thermal/exynos-thermal.txt
>>>>>> +++ b/Documentation/devicetree/bindings/thermal/exynos-thermal.txt
>>>>>> @@ -6,13 +6,16 @@
>>>>>>              "samsung,exynos4412-tmu"
>>>>>>              "samsung,exynos4210-tmu"
>>>>>>              "samsung,exynos5250-tmu"
>>>>>> +            "samsung,exynos5440-tmu"
>>>>>>  - interrupt-parent : The phandle for the interrupt controller
>>>>>> -- reg : Address range of the thermal registers
>>>>>> +- reg : Address range of the thermal registers. For exynos5440-tmu which has 3
>>>>>> +     instances of TMU, 2 set of register has to supplied. First set belongs
>>>>>> +     to each instance of TMU and second set belongs to common TMU registers.
>>>>>>  - interrupts : Should contain interrupt for thermal system
>>>>>>  - clocks : The main clock for TMU device
>>>>>>  - clock-names : Thermal system clock name
>>>>>>
>>>>>> -Example:
>>>>>> +Example 1):
>>>>>>
>>>>>>       tmu@100C0000 {
>>>>>>               compatible = "samsung,exynos4412-tmu";
>>>>>> @@ -23,3 +26,24 @@ Example:
>>>>>>               clock-names = "tmu_apbif";
>>>>>>               status = "disabled";
>>>>>>       };
>>>>>> +
>>>>>> +Example 2):
>>>>>> +
>>>>>> +     tmuctrl_0: tmuctrl@160118 {
>>>>>> +             compatible = "samsung,exynos5440-tmu";
>>>>>> +             reg = <0x160118 0x230>, <0x160368 0x10>;
>>>>>> +             interrupts = <0 58 0>;
>>>>>> +             clocks = <&clock 21>;
>>>>>> +             clock-names = "tmu_apbif";
>>>>>> +     };
>>>>>> +
>>>>>> +Note: For multi-instance tmu each instance should have an alias correctly
>>>>>> +numbered in "aliases" node.
>>>>>> +
>>>>>> +Example:
>>>>>> +
>>>>>> +aliases {
>>>>>> +     tmuctrl0 = &tmuctrl_0;
>>>>>> +     tmuctrl1 = &tmuctrl_1;
>>>>>> +     tmuctrl2 = &tmuctrl_2;
>>>>>> +};
>>>>>> diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
>>>>>> index 7f7b1cf..7ca9c4d 100644
>>>>>> --- a/drivers/thermal/samsung/exynos_tmu.c
>>>>>> +++ b/drivers/thermal/samsung/exynos_tmu.c
>>>>>> @@ -185,9 +185,11 @@ static int exynos_tmu_initialize(struct platform_device *pdev)
>>>>>>                       reg->threshold_th0 + i * sizeof(reg->threshold_th0));
>>>>>>
>>>>>>               writel(reg->inten_rise_mask, data->base + reg->tmu_intclear);
>>>>>> -     } else if (data->soc == SOC_ARCH_EXYNOS) {
>>>>>> +     } else if (data->soc == SOC_ARCH_EXYNOS ||
>>>>>> +                     data->soc == SOC_ARCH_EXYNOS5440) {
>>>>>>               /* Write temperature code for rising and falling threshold */
>>>>>> -             for (i = 0; i < trigger_levs; i++) {
>>>>>> +             for (i = 0;
>>>>>> +             i < trigger_levs && i < EXYNOS_MAX_TRIGGER_PER_REG; i++) {
>>>>>>                       threshold_code = temp_to_code(data,
>>>>>>                                               pdata->trigger_levels[i]);
>>>>>>                       if (threshold_code < 0) {
>>>>>> @@ -218,7 +220,30 @@ static int exynos_tmu_initialize(struct platform_device *pdev)
>>>>>>               writel((reg->inten_rise_mask << reg->inten_rise_shift) |
>>>>>>                       (reg->inten_fall_mask << reg->inten_fall_shift),
>>>>>>                               data->base + reg->tmu_intclear);
>>>>>> +
>>>>>> +             /* if 5th threshold limit is also present, use TH2 register */
>>>>>> +             i = EXYNOS_MAX_TRIGGER_PER_REG;
>>>>>> +             if (pdata->trigger_levels[i]) {
>>>>>> +                     threshold_code = temp_to_code(data,
>>>>>> +                                             pdata->trigger_levels[i]);
>>>>>> +                     if (threshold_code < 0) {
>>>>>> +                             ret = threshold_code;
>>>>>> +                             goto out;
>>>>>> +                     }
>>>>>> +                     rising_threshold =
>>>>>> +                             threshold_code << reg->threshold_th3_l0_shift;
>>>>>> +                     writel(rising_threshold,
>>>>>> +                             data->base + reg->threshold_th2);
>>>>>> +                     if (pdata->trigger_type[i] == HW_TRIP) {
>>>>>> +                             con = readl(data->base + reg->tmu_ctrl);
>>>>>> +                             con |= (1 << reg->therm_trip_en_shift);
>>>>>> +                             writel(con, data->base + reg->tmu_ctrl);
>>>>>> +                     }
>>>>>> +             }
>>>>>>       }
>>>>>> +     /*Clear the PMIN in the common TMU register*/
>>>>>> +     if (reg->tmu_pmin && !data->id)
>>>>>> +             writel(0, data->base_common + reg->tmu_pmin);
>>>>>>  out:
>>>>>>       clk_disable(data->clk);
>>>>>>       mutex_unlock(&data->lock);
>>>>>> @@ -345,7 +370,14 @@ static void exynos_tmu_work(struct work_struct *work)
>>>>>>                       struct exynos_tmu_data, irq_work);
>>>>>>       struct exynos_tmu_platform_data *pdata = data->pdata;
>>>>>>       const struct exynos_tmu_registers *reg = pdata->registers;
>>>>>> -     unsigned int val_irq;
>>>>>> +     unsigned int val_irq, val_type;
>>>>>> +
>>>>>> +     /* Find which sensor generated this interrupt */
>>>>>> +     if (reg->tmu_irqstatus) {
>>>>>> +             val_type = readl(data->base_common + reg->tmu_irqstatus);
>>>>>> +             if (!((val_type >> data->id) & 0x1))
>>>>>> +                     goto out;
>>>>>
>>>>>
>>>>> I have a question about your implementation for supporting EXYNOS5440.
>>>>> I don't know exactly how EXYNO5440's tmu is working, but just guess it would be
>>>>> similar with other EXYNOS series's without number of thermal sensors. (exclusive
>>>>> register map and threshold level). Due to the multiple number of thermal sensor
>>>>> in EXYNOS5440, it have multiple thermal zone devices and that's why it just
>>>>> leave interrupt pin in pending if interrupt is not its, right?
>>>> Yes in 5440 the interrupt line is shared so pending bit is left uncleared.
>>>>>
>>>>> So, my curious is, why we make all platform devices for each of thermal zone
>>>>> devices? Why don't you just handle all thermal zone devices with one platform
>>>>> device?
>>>> Your doubt is genuine. Let me justify my design decision.
>>>> Initially I also thought of making a single platform device but since
>>>> there are 3 different TMU controllers and register maps for 4 more so
>>>> I followed this design as the driver looks clean and can be scalable
>>>> easily. Also I agree that some resources like IRQ line is shared but
>>>> it is due to h/w limitation.
>>>> Also it is easy to cleanly control each TMU instance with the device
>>>> tree data similar to I2C/SPI/MMC instance based device driver. Say I
>>>> do not want to use 2nd sensor then just pass device tree data for 1st
>>>> and 3rd sensor.
>>>>>
>>>>> Yes, It's probably right to make multiple devices node to support them, because
>>>>> it has different physical hardware(sensors). But we have one TMU , don't we?
>>>>> (Maybe my assumption is wrong, I assume that it has one TMU because it looks
>>>>> like it has only one irq line.). If I'm right, I think it is better to manage
>>>>> all thermal zone devices with one platform device. Then, we don't need to leave
>>>>> irq handler with leaving it pendded like above and also we may not need other
>>>>> your patches like adding base_common iomem variable.
>>>> Agreed that base_common variables is extra and present to handle the
>>>> common part. I will further analyse your suggestion.
>>>>
>>>
>>> What is the relation TMU <--> temperature sensor? Is it one to one or
>>> one to many?
>> 1 TMU --- > 1 temp sensor.(one to one)
>>
>
>
> OK. Then it is different to TI bandgap, which has one to many relation.
> Does every TMU has its own resources, like a register map and IRQ?
Yes register maps are different but some registers are common like ISR
related registers. IRQ line is common. However all TMU's are totally
independent devices.
>
>> Thanks,
>> Amit Daniel
>>>
>>>> Thanks,
>>>> Amit Daniel
>>>>>
>>>>> I'd like to listen your opinion about this.
>>>>>
>>>>> Thanks,
>>>>> Jonghwa
>>>>>
>>>>>> +     }
>>>>>>
>>>>>>       exynos_report_trigger(data->reg_conf);
>>>>>>       mutex_lock(&data->lock);
>>>>>> @@ -358,7 +390,7 @@ static void exynos_tmu_work(struct work_struct *work)
>>>>>>
>>>>>>       clk_disable(data->clk);
>>>>>>       mutex_unlock(&data->lock);
>>>>>> -
>>>>>> +out:
>>>>>>       enable_irq(data->irq);
>>>>>>  }
>>>>>>
>>>>>> @@ -520,7 +552,8 @@ static int exynos_tmu_probe(struct platform_device *pdev)
>>>>>>               return ret;
>>>>>>
>>>>>>       if (pdata->type == SOC_ARCH_EXYNOS ||
>>>>>> -                             pdata->type == SOC_ARCH_EXYNOS4210)
>>>>>> +             pdata->type == SOC_ARCH_EXYNOS4210 ||
>>>>>> +                             pdata->type == SOC_ARCH_EXYNOS5440)
>>>>>>               data->soc = pdata->type;
>>>>>>       else {
>>>>>>               ret = -EINVAL;
>>>>>> diff --git a/drivers/thermal/samsung/exynos_tmu.h b/drivers/thermal/samsung/exynos_tmu.h
>>>>>> index 65443d7..9151a30 100644
>>>>>> --- a/drivers/thermal/samsung/exynos_tmu.h
>>>>>> +++ b/drivers/thermal/samsung/exynos_tmu.h
>>>>>> @@ -44,6 +44,7 @@ enum trigger_type {
>>>>>>  enum soc_type {
>>>>>>       SOC_ARCH_EXYNOS4210 = 1,
>>>>>>       SOC_ARCH_EXYNOS,
>>>>>> +     SOC_ARCH_EXYNOS5440,
>>>>>>  };
>>>>>>
>>>>>>  /**
>>>>>> @@ -132,6 +133,8 @@ enum soc_type {
>>>>>>   * @emul_temp_shift: shift bits of emulation temperature.
>>>>>>   * @emul_time_shift: shift bits of emulation time.
>>>>>>   * @emul_time_mask: mask bits of emulation time.
>>>>>> + * @tmu_irqstatus: register to find which TMU generated interrupts.
>>>>>> + * @tmu_pmin: register to get/set the Pmin value.
>>>>>>   */
>>>>>>  struct exynos_tmu_registers {
>>>>>>       u32     triminfo_data;
>>>>>> @@ -199,6 +202,9 @@ struct exynos_tmu_registers {
>>>>>>       u32     emul_temp_shift;
>>>>>>       u32     emul_time_shift;
>>>>>>       u32     emul_time_mask;
>>>>>> +
>>>>>> +     u32     tmu_irqstatus;
>>>>>> +     u32     tmu_pmin;
>>>>>>  };
>>>>>>
>>>>>>  /**
>>>>>> diff --git a/drivers/thermal/samsung/exynos_tmu_data.h b/drivers/thermal/samsung/exynos_tmu_data.h
>>>>>> index 0e2244f..4acf070 100644
>>>>>> --- a/drivers/thermal/samsung/exynos_tmu_data.h
>>>>>> +++ b/drivers/thermal/samsung/exynos_tmu_data.h
>>>>>> @@ -91,6 +91,8 @@
>>>>>>  #define EXYNOS_EMUL_DATA_MASK        0xFF
>>>>>>  #define EXYNOS_EMUL_ENABLE   0x1
>>>>>>
>>>>>> +#define EXYNOS_MAX_TRIGGER_PER_REG   4
>>>>>> +
>>>>>>  #if defined(CONFIG_CPU_EXYNOS4210)
>>>>>>  extern struct exynos_tmu_platform_data const exynos4210_default_tmu_data;
>>>>>>  #define EXYNOS4210_TMU_DRV_DATA (&exynos4210_default_tmu_data)
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>> --
>>> You have got to be excited about what you are doing. (L. Lamport)
>>>
>>> Eduardo Valentin
>>>
>>
>>
>
>
> --
> You have got to be excited about what you are doing. (L. Lamport)
>
> Eduardo Valentin
>
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