From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757278AbXJCCXo (ORCPT ); Tue, 2 Oct 2007 22:23:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754911AbXJCCXh (ORCPT ); Tue, 2 Oct 2007 22:23:37 -0400 Received: from agminet01.oracle.com ([141.146.126.228]:36277 "EHLO agminet01.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753951AbXJCCXg (ORCPT ); Tue, 2 Oct 2007 22:23:36 -0400 Date: Tue, 2 Oct 2007 19:22:09 -0700 From: Randy Dunlap To: Jeff Garzik Cc: ak@suse.de, LKML , Andrew Morton Subject: Re: [PATCH] Document x86-64 iommu kernel parameters Message-Id: <20071002192209.09b2fbda.randy.dunlap@oracle.com> In-Reply-To: <20071003013413.GA17717@havoc.gtf.org> References: <20071003013413.GA17717@havoc.gtf.org> Organization: Oracle Linux Eng. X-Mailer: Sylpheed 2.4.6 (GTK+ 2.8.10; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAQAAAAI= X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2 Oct 2007 21:34:13 -0400 Jeff Garzik wrote: > > Signed-off-by: Jeff Garzik > --- > After having to go figure out what some of these means, I figured I > would save others the trouble. > > Some of these are "best guess" based on a quick scan of the code, so it > certainly needs a sanity review before going upstream. "iommu" is listed in Documentation/x86_64/boot-options.txt along with more x86_64-specific boot options. A few other arches do something similar... > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 4d175c7..8afea9b 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -763,6 +763,30 @@ and is between 256 and 4096 characters. It is defined in the file > > inttest= [IA64] > > + iommu=option[,option..] [X86-64] > + off Disable IOMMU. > + force Unconditionally enable IOMMU. > + noforce Disable IOMMU and IOMMU merging, by default. > + biomerge Unconditionally enable IOMMU, IOMMU merging, > + and set BIO IOMMU vmerge boundary to 4096. > + panic Panic on IOMMU overflow. > + nopanic Do not panic on IOMMU overflow. > + merge Unconditionally enable IOMMU, IOMMU merging. > + nomerge Disable IOMMU merging. > + forcesac Force single address cycle (SAC, 32-bit). > + allowdac Permit dual address cycle (DAC, 64-bit). > + nodac Forbid dual address cycle (DAC, 64-bit). > + soft Enable swiotlb. > + calgary Use Calgary IOMMU. > + > + (GART-only options follow...) > + Specify size of remapping area. > + fullflush Disable optimizing flushing strategy. > + nofullflush Enable optimizing flushing strategy. > + noagp Use entire aperture, AGP isn't using it. > + noaperture Disable aperture fixups / hole init. > + memaper= malloc an aperture of order N. > + > io7= [HW] IO7 for Marvel based alpha systems > See comment before marvel_specify_io7 in > arch/alpha/kernel/core_marvel.c. > - --- ~Randy