From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752324Ab0CJMPb (ORCPT ); Wed, 10 Mar 2010 07:15:31 -0500 Received: from mail-ww0-f46.google.com ([74.125.82.46]:51989 "EHLO mail-ww0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751090Ab0CJMP1 (ORCPT ); Wed, 10 Mar 2010 07:15:27 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=lovU7QDj3F82KH7RExZZC4NO2MxOicu5Kf5ROsLVzRuQe2iKW6Wv3gDQCCIgR8x9+y 91ZFpss2tTGF7tOq+PMyM9KRPcts2kzYEBLFjGUpyRM/uq61Oa9d+ipbPZupJTdBCU8/ oBTNIkLSTqmEfp/mJ3Mq06T2D8EMkGH36zdNM= MIME-Version: 1.0 In-Reply-To: <21eaeb5a1003100120x6cd3f69ak598954af3c9fe955@mail.gmail.com> References: <4B968834.3040609@gmail.com> <21eaeb5a1003091808s2d7638cxd524952a7d84b378@mail.gmail.com> <2ea1731b1003100002w104633ffy1ae46ef3d245e5b5@mail.gmail.com> <21eaeb5a1003100120x6cd3f69ak598954af3c9fe955@mail.gmail.com> Date: Wed, 10 Mar 2010 13:15:25 +0100 Message-ID: <2ea1731b1003100415i46dd8fcem85b85f49fb1a479@mail.gmail.com> Subject: Re: [PATCH v2] char drivers: Ram oops/panic logger From: Marco Stornelli To: Yuasa Yoichi Cc: Linux Kernel , Linux Embedded Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2010/3/10 Yuasa Yoichi : > 2010/3/10 Marco Stornelli : >> 2010/3/10 Yuasa Yoichi : >>> Hi, >>> >>> 2010/3/10 Marco Stornelli : >>>> Ramoops, like mtdoops, can log oops/panic information but in RAM. >>> >>> What is different from mtdoops + mtd-ram? >>> >>> Yoichi >>> >> >> It can be used in a very easy way with persistent RAM for systems >> without flash support. For this systems, with this driver, it's no >> more needed add to the kernel the mtd subsystem with advantage in >> footprint as I said in the description. > > right. > But, > >> In addition, you can save >> flash space and store this information only in RAM. I think it's very >> useful for embedded systems. > > CONFIG_MTD_RAM uses only RAM. > I think there's no big difference about this point. > I meant with the "classic" use of mtdoops, therefore with a flash partition without use MTD_RAM. Using MTD_RAM, it's more or less the same thing, with the exception of "where" you want deploy the log. For example: if in your system you have got a nvram you can use it without problem, you need to specify the address of the nvram to the module. Very simple. I think it's a small driver but very useful, feedback from other embedded guys are welcome. Marco