From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from penguin.netx4.com (embeddededge.com [209.113.146.155]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id AAE7D679F4 for ; Tue, 17 May 2005 06:31:11 +1000 (EST) In-Reply-To: <4288E10A.9030408@mvista.com> References: <1116222720.5095.86.camel@gaston> <7d5cfed0ee1edade8050d2c4da94b3f1@freescale.com> <1116255938.5095.133.camel@gaston> <1116261725.5095.139.camel@gaston> <4288DFCB.2080208@mvista.com> <4288E10A.9030408@mvista.com> Mime-Version: 1.0 (Apple Message framework v622) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <2dd506f0a6d4b03e771c0bc9d80735e6@embeddededge.com> From: Dan Malek Date: Mon, 16 May 2005 16:31:01 -0400 To: "Mark A. Greer" Cc: linuxppc-dev@ozlabs.org, John Reiser Subject: Re: 2GB address space limit on 32-bit PowerPC Macintosh List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On May 16, 2005, at 2:06 PM, Mark A. Greer wrote: > Oops... > /me unintentionally stepped into the middle of a flame war :) Just pee on it :-) > To be clear, "offender" == board that has an io_block_mapping below > the 3 GB line. That is one of the obvious changes. You are likely to find some other assumptions that may need attention. The problem with io_block_mapping is you just can't remove it, you have to fix up all of the code that is based on the assumption these spaces are mapped. You are likely to find yourself in a situation where you need access to some board control registers before VM is set up and you can call ioremap(). So, you will find yourself doing some hack in head.S to map BAT registers to get access to this, which is exactly what io_block_mapping() does, only in a way that is obvious :-) Thanks. -- Dan