From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 21 May 2001 07:03:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 21 May 2001 07:03:33 -0400 Received: from penguin.e-mind.com ([195.223.140.120]:42364 "EHLO penguin.e-mind.com") by vger.kernel.org with ESMTP id ; Mon, 21 May 2001 07:03:18 -0400 Date: Mon, 21 May 2001 13:00:34 +0200 From: Andrea Arcangeli To: "David S. Miller" Cc: Andrew Morton , Ivan Kokshaysky , Richard Henderson , linux-kernel@vger.kernel.org Subject: Re: alpha iommu fixes Message-ID: <20010521130034.L30738@athlon.random> In-Reply-To: <3B07CF20.2ABB5468@uow.edu.au> <20010520163323.G18119@athlon.random> <15112.26868.5999.368209@pizda.ninka.net> <20010521034726.G30738@athlon.random> <15112.48708.639090.348990@pizda.ninka.net> <20010521105944.H30738@athlon.random> <15112.55709.565823.676709@pizda.ninka.net> <20010521115631.I30738@athlon.random> <15112.59880.127047.315855@pizda.ninka.net> <15112.60362.447922.780857@pizda.ninka.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <15112.60362.447922.780857@pizda.ninka.net>; from davem@redhat.com on Mon, May 21, 2001 at 03:19:54AM -0700 X-GnuPG-Key-URL: http://e-mind.com/~andrea/aa.gnupg.asc X-PGP-Key-URL: http://e-mind.com/~andrea/aa.asc Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 21, 2001 at 03:19:54AM -0700, David S. Miller wrote: > max bytes per bttv: max_gbuffers * max_gbufsize > 64 * 0x208000 == 133.12MB > > 133.12MB * 8 PCI slots == ~1.06 GB > > Which is still only half of the total IOMMU space available per > controller. and it is the double of the iommu space that I am going to reserve for pci dynamic mappings on the tsunami (right now it is 128Mbyte... and I'll change to 512mbyte) also bttv is not doing that a large dma and by default it only uses 2 buffers in the ring. bttv is not a good example of what can really overflow the pci virtual address space in real life (when I mentioned it it was only to point out it still uses virt_to_bus), filling a pci bus with bttv cards sounds quite silly anyways ;) Andrea