Re: [PATCH 3/3] thermal: exynos: Handle the misplaced TRIMINFO register

From: Naveen Krishna Ch
Date: Wed Aug 28 2013 - 02:20:23 EST

On 28 August 2013 11:33, amit daniel kachhap <amit.daniel@xxxxxxxxxxx> wrote:
> Hi Naveen
>
> On Wed, Aug 28, 2013 at 11:15 AM, Naveen Krishna Chatradhi
> <ch.naveen@xxxxxxxxxxx> wrote:
>> This patch adds code to handle the misplaced TRIMINFO register
>> incase of Exynos5420.
>>
>> On Exynos5420 we have a TRIMINFO register being misplaced for
>> TMU channels 2, 3 and 4
>>
>> TRIMINFO at 0x1006c000 contains data for TMU channel 3
>> TRIMINFO at 0x100a0000 contains data for TMU channel 4
>> TRIMINFO at 0x10068000 contains data for TMU channel 2
>>
>> The misplaced register address is passed through devicetree and
>> map it seperately during probe.
>> Also, adds the documentation under devicetree/bindings/thermal/
>>
>> Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@xxxxxxxxxxx>
>> ---
>> .../devicetree/bindings/thermal/exynos-thermal.txt | 21 +++++++++++++
>> drivers/thermal/samsung/exynos_tmu.c | 32 +++++++++++++++++---
>> 2 files changed, 49 insertions(+), 4 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/thermal/exynos-thermal.txt b/Documentation/devicetree/bindings/thermal/exynos-thermal.txt
>> index 284f530..e818473 100644
>> --- a/Documentation/devicetree/bindings/thermal/exynos-thermal.txt
>> +++ b/Documentation/devicetree/bindings/thermal/exynos-thermal.txt
>> @@ -7,12 +7,21 @@
>> "samsung,exynos4210-tmu"
>> "samsung,exynos5250-tmu"
>> "samsung,exynos5440-tmu"
>> + "samsung,exynos5420-tmu"
>> - interrupt-parent : The phandle for the interrupt controller
>> - reg : Address range of the thermal registers. For soc's which has multiple
>> instances of TMU and some registers are shared across all TMU's like
>> interrupt related then 2 set of register has to supplied. First set
>> belongs to each instance of TMU and second set belongs to common TMU
>> registers.
>> +
>> + ** NOTE FOR EXYNOS5420 **
>> + TRIMINFO register is being misplaced for TMU channels 2, 3 and 4
>> +
>> + TERMINFO for TMU channel 2 is present in address space of TMU channel 3
>> + TERMINFO for TMU channel 3 is present in address space of TMU channel 4
>> + TERMINFO for TMU channel 4 is present in address space of TMU channel 2
>> +
>> - interrupts : Should contain interrupt for thermal system
>> - clocks : The main clock for TMU device
>> - clock-names : Thermal system clock name
>> @@ -43,6 +52,18 @@ Example 2):
>> clock-names = "tmu_apbif";
>> };
>>
>> +Example 3): In case of Exynos5420 TMU channel 3
>> +
>> + /* tmu for CPU3 */
>> + tmu@1006c000 {
>> + compatible = "samsung,exynos5420-tmu";
>> + /* 2nd reg is for the misplaced TRIMINFO register */
>> + reg = <0x1006c000 0x100>, <0x100a0000 0x4>;
>> + interrupts = <0 185 0>;
>> + clocks = <&clock 318>;
>> + clock-names = "tmu_apbif";
>> + };
>> +
>> Note: For multi-instance tmu each instance should have an alias correctly
>> numbered in "aliases" node.
>>
>> diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
>> index bfdfbd6..f95844e 100644
>> --- a/drivers/thermal/samsung/exynos_tmu.c
>> +++ b/drivers/thermal/samsung/exynos_tmu.c
>> @@ -42,6 +42,7 @@
>> * @pdata: pointer to the tmu platform/configuration data
>> * @base: base address of the single instance of the TMU controller.
>> * @base_common: base address of the common registers of the TMU controller.
>> + * @triminfo_base: misplaced register base for TRIMINFO on Exynos5420 only
>
> Instead of creating this new field you can re-use base_common for
> accessing the second set of register for misplaced triminfo address.
> Also you can rename this variable as base_second.

The purpose and the meaning of the fields are entirely different.
The triminfo is a hardware bug present only in Exynos5420
and the common registers are available only on Exynos5440 i guess.

IMHO, reusing is not a nice idea.
I'm willing to modify the code if there is a better idea.
>
>> * @irq: irq number of the TMU controller.
>> * @soc: id of the SOC type.
>> * @irq_work: pointer to the irq work structure.
>> @@ -57,6 +58,7 @@ struct exynos_tmu_data {
>> struct exynos_tmu_platform_data *pdata;
>> void __iomem *base;
>> void __iomem *base_common;
>> + void __iomem *triminfo_base; /* Needed only Exynos5420 */
>> int irq;
>> enum soc_type soc;
>> struct work_struct irq_work;
>> @@ -186,7 +188,12 @@ static int exynos_tmu_initialize(struct platform_device *pdev)
>> EXYNOS5440_EFUSE_SWAP_OFFSET + reg->triminfo_data);
>> }
>> } else {
>> - trim_info = readl(data->base + reg->triminfo_data);
>> + /* On exynos5420 TRIMINFO is misplaced for some channels */
>> + if (data->triminfo_base)
>> + trim_info = readl(data->triminfo_base +
>> + reg->triminfo_data);
>> + else
>> + trim_info = readl(data->base + reg->triminfo_data);
>> }
>> data->temp_error1 = trim_info & EXYNOS_TMU_TEMP_MASK;
>> data->temp_error2 = ((trim_info >> reg->triminfo_85_shift) &
>> @@ -586,8 +593,17 @@ static int exynos_map_dt_data(struct platform_device *pdev)
>> * Check if the TMU shares some registers and then try to map the
>> * memory of common registers.
>> */
>> - if (!TMU_SUPPORTS(pdata, SHARED_MEMORY))
>> + if (!TMU_SUPPORTS(pdata, SHARED_MEMORY)) {
>> + /* For Exynos5420 The misplaced TERMINFO register address will
>> + * be passed from device tree node.
>> + *
>> + * We cannot use devm_request_and_ioremap, as the base address
>> + * over laps with the address space of the other TMU channel.
>> + * Check Documentation for details
>> + */
>> + data->triminfo_base = of_iomap(pdev->dev.of_node, 1);
>> return 0;
>> + }
> In the below code, remove the request resource API for common_base and
> use simple of_iomap API.

That will be a separate fix patch. Will submit separately,
This patchset is to add exynos5420 support

Is the res_size for the common registers fixed ?

>
> Thanks,
> Amit Daniel
>>
>> if (of_address_to_resource(pdev->dev.of_node, 1, &res)) {
>> dev_err(&pdev->dev, "failed to get Resource 1\n");
>> @@ -632,12 +648,13 @@ static int exynos_tmu_probe(struct platform_device *pdev)
>> data->clk = devm_clk_get(&pdev->dev, "tmu_apbif");
>> if (IS_ERR(data->clk)) {
>> dev_err(&pdev->dev, "Failed to get clock\n");
>> - return PTR_ERR(data->clk);
>> + ret = PTR_ERR(data->clk);
>> + goto err_triminfo_base;
>> }
>>
>> ret = clk_prepare(data->clk);
>> if (ret)
>> - return ret;
>> + goto err_triminfo_base;
>>
>> if (pdata->type == SOC_ARCH_EXYNOS ||
>> pdata->type == SOC_ARCH_EXYNOS4210 ||
>> @@ -707,9 +724,13 @@ static int exynos_tmu_probe(struct platform_device *pdev)
>> }
>>
>> return 0;
>> +
>> err_clk:
>> clk_unprepare(data->clk);
>> return ret;
>> +err_triminfo_base:
>> + if (data->triminfo_base)
>> + iounmap(data->triminfo_base);
>> }
>>
>> static int exynos_tmu_remove(struct platform_device *pdev)
>> @@ -720,6 +741,9 @@ static int exynos_tmu_remove(struct platform_device *pdev)
>>
>> exynos_unregister_thermal(data->reg_conf);
>>
>> + if (data->triminfo_base)
>> + iounmap(data->triminfo_base);
>> +
>> clk_unprepare(data->clk);
>>
>> if (!IS_ERR(data->regulator))
>> --
>> 1.7.9.5
>>
>> --
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