From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753758AbZENVsc (ORCPT ); Thu, 14 May 2009 17:48:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753016AbZENVsX (ORCPT ); Thu, 14 May 2009 17:48:23 -0400 Received: from az33egw02.freescale.net ([192.88.158.103]:38967 "EHLO az33egw02.freescale.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752831AbZENVsW (ORCPT ); Thu, 14 May 2009 17:48:22 -0400 Date: Thu, 14 May 2009 16:48:19 -0500 From: Scott Wood To: Heiko Schocher Cc: Wolfgang Denk , linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [PowerPC] MPC8272ADS: fix device tree for 8 MB flash, size Message-ID: <20090514214819.GA15549@b07421-ec1.am.freescale.net> References: <4A0A683B.5010209@denx.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A0A683B.5010209@denx.de> User-Agent: Mutt/1.4.1i X-Brightmail-Tracker: AAAAAQAAAWE= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 13, 2009 at 08:27:07AM +0200, Heiko Schocher wrote: > Hello Wolfgang, > > > The current device tree for the MPC8272ADS assumes a mapping of 32 MB > > of NOR flash at 0xFE00.0000, while there are actually only 8 MB on > > the boards, mapped at 0xFF80.0000. When booting an uImage with such a > > device tree, the kernel crashes because 0xFE00.0000 is not mapped. > > Wouldn;t it be better, if u-boot fixes the device tree entries? We should proabbly leave out the ranges altogether, and have u-boot populate it from the mappings it establishes. > I think, u-boot should know, where the flash begins and ends, and > because this is maybe a dynamic variable for this board, it should > be better, if u-boot fixes this, so no need for adding a device tree > for every board variant. Flash is on a SIMM on this board, and the board manual says it's expandable to 32 MiB. However, I suspect that the current DTS was just an error as I based it on a board that had not had its flash SIMM modified. That specific flash SIMM is no longer working (or perhaps just got its contents corrupted -- one of these days I may hook up a BDI and try to reflash), so I can't go back and check. I don't see how current u-boot would accomodate more than 8MiB flash on this board (there's some detection in board/freescale/mpc8260ads/flash.c, but I don't see any setting of BR0 besides the preliminary value at 0xff800000). -Scott From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw02.freescale.net (az33egw02.freescale.net [192.88.158.103]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw02.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 04EB6DE01F for ; Fri, 15 May 2009 07:48:24 +1000 (EST) Received: from de01smr02.am.mot.com (de01smr02.freescale.net [10.208.0.151]) by az33egw02.freescale.net (8.14.3/az33egw02) with ESMTP id n4ELmKlW017236 for ; Thu, 14 May 2009 14:48:21 -0700 (MST) Received: from b07421-ec1.am.freescale.net (b07421-ec1.am.freescale.net [10.82.121.43]) by de01smr02.am.mot.com (8.13.1/8.13.0) with ESMTP id n4ELmJpd015146 for ; Thu, 14 May 2009 16:48:20 -0500 (CDT) Date: Thu, 14 May 2009 16:48:19 -0500 From: Scott Wood To: Heiko Schocher Subject: Re: [PATCH] [PowerPC] MPC8272ADS: fix device tree for 8 MB flash, size Message-ID: <20090514214819.GA15549@b07421-ec1.am.freescale.net> References: <4A0A683B.5010209@denx.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <4A0A683B.5010209@denx.de> Cc: linuxppc-dev@ozlabs.org, Wolfgang Denk , linux-kernel@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, May 13, 2009 at 08:27:07AM +0200, Heiko Schocher wrote: > Hello Wolfgang, > > > The current device tree for the MPC8272ADS assumes a mapping of 32 MB > > of NOR flash at 0xFE00.0000, while there are actually only 8 MB on > > the boards, mapped at 0xFF80.0000. When booting an uImage with such a > > device tree, the kernel crashes because 0xFE00.0000 is not mapped. > > Wouldn;t it be better, if u-boot fixes the device tree entries? We should proabbly leave out the ranges altogether, and have u-boot populate it from the mappings it establishes. > I think, u-boot should know, where the flash begins and ends, and > because this is maybe a dynamic variable for this board, it should > be better, if u-boot fixes this, so no need for adding a device tree > for every board variant. Flash is on a SIMM on this board, and the board manual says it's expandable to 32 MiB. However, I suspect that the current DTS was just an error as I based it on a board that had not had its flash SIMM modified. That specific flash SIMM is no longer working (or perhaps just got its contents corrupted -- one of these days I may hook up a BDI and try to reflash), so I can't go back and check. I don't see how current u-boot would accomodate more than 8MiB flash on this board (there's some detection in board/freescale/mpc8260ads/flash.c, but I don't see any setting of BR0 besides the preliminary value at 0xff800000). -Scott