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 652F0DDE23 for ; Thu, 23 Oct 2008 09:49:05 +1100 (EST) Subject: Re: Extended Addressing Mode From: Benjamin Herrenschmidt To: Matt Sealey In-Reply-To: <48FFA755.5050808@genesi-usa.com> References: <48FEEB88.6050505@kontron.com> <83735324-C37B-4C57-A50F-FFF0D133E4E3@kernel.crashing.org> <48FF23C4.5030408@kontron.com> <88C8EDEB-C9A5-4876-AF7D-55CBABBE111D@kernel.crashing.org> <1224713506.7654.353.camel@pasglop> <48FFA755.5050808@genesi-usa.com> Content-Type: text/plain Date: Thu, 23 Oct 2008 09:48:35 +1100 Message-Id: <1224715715.7654.355.camel@pasglop> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, =?ISO-8859-1?Q?R=E9gis_Odey=E9?= 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, 2008-10-22 at 17:21 -0500, Matt Sealey wrote: > > Because we're Genesi! And we have a firmware solution that > kind of has to keep 32-bit pointers in the unlikely event that > someone actually uses the client interface (besides yaboot!). > > Having I/O in the 36-bit range could cause all sorts of > explosions, and we're running real-mode so trapping and faking > I/O accesses is REALLy difficult :} how so ? we have plethora of 32-bit firmwares including OF implementations that can perfectly address 36 bit physical address space. Nothing to do with having 32-bit pointers. Cheers, Ben.