From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22555 invoked by alias); 3 Jun 2009 11:52:18 -0000 Received: (qmail 22545 invoked by uid 22791); 3 Jun 2009 11:52:17 -0000 X-SWARE-Spam-Status: No, hits=-1.4 required=5.0 tests=AWL,BAYES_20 X-Spam-Check-By: sourceware.org Received: from mail05.solnet.ch (HELO mail05.solnet.ch) (212.101.4.139) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 03 Jun 2009 11:52:11 +0000 Received: from mail05.solnet.ch ([127.0.0.1]) by localhost (mail05.solnet.ch [127.0.0.1]) (SolNet-Check, port 10024) with LMTP id JR2wxRbJvLPZ; Wed, 3 Jun 2009 11:52:08 +0000 (UTC) Received: from beta.intefo.ch (static-212-101-18-64.adsl.solnet.ch [212.101.18.64]) by mail05.solnet.ch (Postfix) with ESMTP id 1B3A239963; Wed, 3 Jun 2009 11:52:08 +0000 (UTC) Received: from beta.intefo.ch ([127.0.0.1]) by localhost (beta.intefo.ch [127.0.0.1]) (amavisd-new, port 10024) with LMTP id L0emGs06NX7l; Wed, 3 Jun 2009 13:52:07 +0200 (CEST) Received: from [192.168.1.20] (simon.intefo.ch [192.168.1.20]) by beta.intefo.ch (Postfix) with ESMTP id 3142B7700E9; Wed, 3 Jun 2009 13:52:07 +0200 (CEST) Message-ID: <4A2663FB.4010408@intefo.ch> Date: Wed, 03 Jun 2009 11:52:00 -0000 From: Simon Kallweit User-Agent: Thunderbird 2.0.0.21 (X11/20090318) MIME-Version: 1.0 To: Andrew Lunn CC: Ross Younger , "ecos-devel@ecos.sourceware.org" Subject: Re: NAND review References: <4A126D59.7070404@intefo.ch> <20090519162853.GA27459@lunn.ch> <20090603085115.GA27508@lunn.ch> <4A264E85.6030202@ecoscentric.com> <20090603104817.GC27508@lunn.ch> In-Reply-To: <20090603104817.GC27508@lunn.ch> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact ecos-devel-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-devel-owner@ecos.sourceware.org X-SW-Source: 2009-06/txt/msg00008.txt.bz2 Andrew Lunn wrote: >> The philosophical question for us all is whether NAND on its own should be >> allowed to use malloc, given that a NAND array will probably always be used >> in conjunction with a log-structured filesystem which will chew up >> comparatively large amounts of RAM (and, of course, RAM is forever getting >> cheaper). Is this a corner or even N-dimensional vertex case; will it >> necessarily always be the case that a device with NAND flash will have >> enough RAM to support it? Do boards with NAND but not much RAM exist, and if >> so do we care about them? > > The answer is yes. Simon, could you describe your board. From what i > understand you don't have much RAM. Well yes, our current hardware has 512k on-chip flash, 64k on-chip ram and 128k external ram. For additional storage we currently have a 4mb NOR flash, but we're planning on replacing this with a NAND flash so we can run a tiny filesystem like UFFS. The current software does only use static memory with the exception of lwIP, which uses fixed memory pools for dynamic allocation. For upcoming products we were thinking about getting rid of the external ram, which would leave us with only 64k. But this certainly would lead to problems in other areas as well. Simon