From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 9CAC8DE1B2 for ; Thu, 10 Jul 2008 06:43:56 +1000 (EST) Subject: Re: [PATCH] powerpc: Fix problems with 32bit PPC's running with more than 2GB of RAM From: Benjamin Herrenschmidt To: Josh Boyer In-Reply-To: <20080709162219.4c07a67e@zod.rchland.ibm.com> References: <1215611076-13518-1-git-send-email-sr@denx.de> <1215633758.8970.372.camel@pasglop> <20080709162219.4c07a67e@zod.rchland.ibm.com> Content-Type: text/plain Date: Thu, 10 Jul 2008 06:39:39 +1000 Message-Id: <1215635979.8970.385.camel@pasglop> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, Stefan Roese Reply-To: benh@kernel.crashing.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2008-07-09 at 16:22 -0400, Josh Boyer wrote: > On Thu, 10 Jul 2008 06:02:38 +1000 > Benjamin Herrenschmidt wrote: > > > On Wed, 2008-07-09 at 15:44 +0200, Stefan Roese wrote: > > > This patch enables 32bit PPC's (with 36bit physical address space, e.g. > > > IBM/AMCC PPC44x) to run with more than 2GB of RAM. Mostly its just > > > replacing types (unsigned long -> phys_addr_t). > > > > > > Tested on an AMCC Katmai with 4GB of DDR2. > > > > > > Signed-off-by: Stefan Roese > > > > But DMAs will break no ? > > How? Hrm... forget it. It's fine up to 4G of RAM... (ie. as long as DMA is below 32 bits). Ben.