[PATCH v4 05/12] ARM: EXYNOS: add support uart for EXYNOS4 and EXYNOS5

Kukjin Kim kgene.kim at samsung.com
Wed Mar 28 22:05:53 EDT 2012


Thomas Abraham wrote:
> 2012/3/22 Kukjin Kim<kgene.kim at samsung.com>:
>> On 03/21/12 03:45, Marek Szyprowski wrote:
>>>
>>> Hello,
>>>
>>> On Wednesday, March 21, 2012 10:14 AM Thomas Abraham wrote:
>>>
>>>> On 14 March 2012 20:12, Kukjin Kim<kgene.kim at samsung.com>    wrote:
>>>>>
>>>>> Actually, the base address of uart is different between EXYNOS4
>>>>> and EXYNOS5 and this patch enables to support uart for EXYNOS4
>>>>> and EXYNOS5 SoCs at runtime.
>>>>>
>>>>> Signed-off-by: Kukjin Kim<kgene.kim at samsung.com>
>>>>> ---
>>>>
>>>>
>>>> [...]
>>>>
>>>>> diff --git a/arch/arm/mach-exynos/include/mach/debug-macro.S
>>>>> b/arch/arm/mach-
>>>>
>>>> exynos/include/mach/debug-macro.S
>>>>>
>>>>> index 6cacf16..6c857ff 100644
>>>>> --- a/arch/arm/mach-exynos/include/mach/debug-macro.S
>>>>> +++ b/arch/arm/mach-exynos/include/mach/debug-macro.S
>>>>> @@ -21,8 +21,13 @@
>>>>>          */
>>>>>
>>>>>         .macro addruart, rp, rv, tmp
>>>>> -               ldr     \rp, = S3C_PA_UART
>>>>> -               ldr     \rv, = S3C_VA_UART
>>>>> +               mov     \rp, #0x10000000
>>>>
>>>>
>>>> This is physical address of Exynos4/5 CPUID register which cannot be
>>>> used here. And virtual address S5P_VA_CPUID also cannot be used here
>>>> since this will be called before paging_init when earlyprintk boot
>>>> param is used. So, with this change, earlyprintk does not work for
>>>> both Exynos4 and Exynos5.
>>>
>>>
>>> I confirm, printascii freeze the system on EXYNOS4 after that patch,
>>> tested on Exynos4210 Nuri board.
>>>
>> Hi,
>>
>> I think, it can be solved with following and if no problems, it will be
>> fixed during v3.4-rcX.
>>
>> diff --git a/arch/arm/mach-exynos/include/mach/debug-macro.S
>> b/arch/arm/mach-exynos/in
>> index 6c857ff..a865417 100644
>> --- a/arch/arm/mach-exynos/include/mach/debug-macro.S
>> +++ b/arch/arm/mach-exynos/include/mach/debug-macro.S
>> @@ -21,10 +21,10 @@
>>
>>          */
>>
>>         .macro addruart, rp, rv, tmp
>> -               mov     \rp, #0x10000000
>> -               ldr     \rp, [\rp, #0x0]
>> -               and     \rp, \rp, #0xf00000
>> -               teq     \rp, #0x500000          @@ EXYNOS5
>> +               mrc     p15, 0, \tmp, c0, c0, 0
>> +               and     \tmp, \tmp, #0xf0
>> +               teq     \tmp, #0xf0             @@ A15
>> +
>>                 ldreq   \rp, =EXYNOS5_PA_UART
>>
>>                 movne   \rp, #EXYNOS4_PA_UART   @@ EXYNOS4
>>                 ldr     \rv, =S3C_VA_UART
>>
>
> Dear Mr. Kim,
>
> I have tested the above patch on Exynos5. Thanks.
>
> Tested-by: Thomas Abraham<thomas.abraham at linaro.org>

Hi Marek, Thomas,

Thanks for your test.
I will apply above patch with your 'Tested-by:...'

Thanks.

Best regards,
Kgene.
--
Kukjin Kim <kgene.kim at samsung.com>, Senior Engineer,
SW Solution Development Team, Samsung Electronics Co., Ltd.



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