From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Figa Subject: Re: [PATCH 4/5] ARM: S3C24XX: convert boards to use common restart function Date: Fri, 24 Jan 2014 11:08:58 +0100 Message-ID: <52E23BBA.7020804@gmail.com> References: <3105326.uFdOVLyXH8@phil> <3955130.WSqWacB8SI@phil> <52E19931.80803@gmail.com> <1873916.c2IkPH5hCW@phil> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-ea0-f174.google.com ([209.85.215.174]:52289 "EHLO mail-ea0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751053AbaAXKJE (ORCPT ); Fri, 24 Jan 2014 05:09:04 -0500 Received: by mail-ea0-f174.google.com with SMTP id b10so887381eae.33 for ; Fri, 24 Jan 2014 02:09:02 -0800 (PST) In-Reply-To: <1873916.c2IkPH5hCW@phil> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: =?ISO-8859-1?Q?Heiko_St=FCbner?= Cc: Tomasz Figa , linux-samsung-soc@vger.kernel.org, kgene.kim@samsung.com, linux-arm-kernel@lists.infradead.org On 24.01.2014 09:03, Heiko St=FCbner wrote: > On Thursday 23 January 2014 23:35:29 Tomasz Figa wrote: >> On 23.01.2014 20:02, Heiko St=FCbner wrote: >>> Am Donnerstag, 23. Januar 2014, 19:51:34 schrieb Tomasz Figa: >>>> On 23.01.2014 19:36, Heiko St=FCbner 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 a= ll >>> s3c24xx soc variants. >> >> If you make SAMSUNG_WDT_RESET always selected on S3C24XX then I gues= s >> it's fine. >> >>>> Note that you can make the restart field NULL in mach_desc in boar= d >>>> files. >>> >>> As I said above, this is mainly meant for the dt-case. The legacy-b= oard >>> 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 an= d no >> special handling of those with swrst would be needed. > > According to the manuals I looked at, all S3C24XX SoCs seem to suppor= t the > watchdog reset - I'm not sure why the swrst variant was choosen for t= he newer > ones when they were added initially. So yes in theory all of them see= m to be > able to use the watchdog reset. > > But in any case the s3c2412 will need its own handling, due to the ap= parent > 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 SWRS= T=20 in clock driver if available should work. Best regards, Tomasz