From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 22 May 2001 17:04:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 22 May 2001 17:04:18 -0400 Received: from are.twiddle.net ([64.81.246.98]:34177 "EHLO are.twiddle.net") by vger.kernel.org with ESMTP id ; Tue, 22 May 2001 17:04:04 -0400 Date: Tue, 22 May 2001 14:02:06 -0700 From: Richard Henderson To: Jonathan Lundell Cc: Andrea Arcangeli , Ivan Kokshaysky , linux-kernel@vger.kernel.org, "David S. Miller" Subject: Re: alpha iommu fixes Message-ID: <20010522140206.B4662@twiddle.net> Mail-Followup-To: Jonathan Lundell , Andrea Arcangeli , Ivan Kokshaysky , linux-kernel@vger.kernel.org, "David S. Miller" In-Reply-To: <15112.62766.368436.236478@pizda.ninka.net> <20010521131959.M30738@athlon.random> <20010521155151.A10403@jurassic.park.msu.ru> <20010521105339.A1907@twiddle.net> <20010522025658.A1116@athlon.random> <20010522162916.B15155@athlon.random> <20010522184409.A791@jurassic.park.msu.ru> <20010522170016.D15155@athlon.random> <20010522132815.A4573@twiddle.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: ; from jlundell@pobox.com on Tue, May 22, 2001 at 01:48:23PM -0700 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 22, 2001 at 01:48:23PM -0700, Jonathan Lundell wrote: > 64KB for 8-bit DMA; 128KB for 16-bit DMA. [...] This doesn't > apply to bus-master DMA, just the legacy (8237) stuff. Would this 8237 be something on the ISA card, or something on the old pc mainboards? I'm wondering if we can safely ignore this issue altogether here... > There was also a 24-bit address limitation. Yes, that's in the number of address lines going to the isa card. We work around that one by having an iommu arena from 8M to 16M and forcing all ISA traffic to go through there. r~