From mboxrd@z Thu Jan  1 00:00:00 1970
From: tomasz.figa@gmail.com (Tomasz Figa)
Date: Fri, 24 Jan 2014 11:08:58 +0100
Subject: [PATCH 4/5] ARM: S3C24XX: convert boards to use common restart
 function
In-Reply-To: <1873916.c2IkPH5hCW@phil>
References: <3105326.uFdOVLyXH8@phil> <3955130.WSqWacB8SI@phil>
 <52E19931.80803@gmail.com> <1873916.c2IkPH5hCW@phil>
Message-ID: <52E23BBA.7020804@gmail.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org



On 24.01.2014 09:03, Heiko St?bner wrote:
> On Thursday 23 January 2014 23:35:29 Tomasz Figa wrote:
>> On 23.01.2014 20:02, Heiko St?bner wrote:
>>> Am Donnerstag, 23. Januar 2014, 19:51:34 schrieb Tomasz Figa:
>>>> On 23.01.2014 19:36, Heiko St?bner wrote:
>>> In general, I want to try establishing some sort of general restart way,
>>> as in the future one dt-board should hopefully be enough to cover all
>>> s3c24xx soc variants.
>>
>> If you make SAMSUNG_WDT_RESET always selected on S3C24XX then I guess
>> it's fine.
>>
>>>> Note that you can make the restart field NULL in mach_desc in board
>>>> files.
>>>
>>> As I said above, this is mainly meant for the dt-case. The legacy-board
>>> files are more or less only secondary, and the affected boards can of
>>> course then have a NULL restart handle :-) .
>>>
>>> So for this the dt-board could simply use the wdt-reset, which then gets
>>> replaced by the ccf-based reset if appropriate.
>>
>> OK. By the way, are there any benefits of using this software reset over
>> watchdog reset? Maybe all S3C24xx could simply use watchdog reset and no
>> special handling of those with swrst would be needed.
>
> According to the manuals I looked at, all S3C24XX SoCs seem to support the
> watchdog reset - I'm not sure why the swrst variant was choosen for the newer
> ones when they were added initially. So yes in theory all of them seem to be
> able to use the watchdog reset.
>
> But in any case the s3c2412 will need its own handling, due to the apparent
> clock problem during resets (mentioned in the code and the manuals of
> s3c2412/s3c2413).

OK. So WDT by default (always selected in Kconfig) and override to SWRST 
in clock driver if available should work.

Best regards,
Tomasz