From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753714Ab3JFOFK (ORCPT ); Sun, 6 Oct 2013 10:05:10 -0400 Received: from terminus.zytor.com ([198.137.202.10]:46671 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753635Ab3JFOFF (ORCPT ); Sun, 6 Oct 2013 10:05:05 -0400 Date: Sun, 6 Oct 2013 07:04:48 -0700 From: tip-bot for Ingo Molnar Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, ak@linux.intel.com, tglx@linutronix.de, borislav.petkov@amd.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, ak@linux.intel.com, tglx@linutronix.de, borislav.petkov@amd.com To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/iommu] x86/iommu: Clean up the CONFIG_GART_IOMMU config option a bit Git-Commit-ID: ced3c42c9fcba049ec9c76c8461ac194cafb20ba X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (terminus.zytor.com [127.0.0.1]); Sun, 06 Oct 2013 07:04:55 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: ced3c42c9fcba049ec9c76c8461ac194cafb20ba Gitweb: http://git.kernel.org/tip/ced3c42c9fcba049ec9c76c8461ac194cafb20ba Author: Ingo Molnar AuthorDate: Sun, 6 Oct 2013 11:45:20 +0200 Committer: Ingo Molnar CommitDate: Sun, 6 Oct 2013 15:58:41 +0200 x86/iommu: Clean up the CONFIG_GART_IOMMU config option a bit Improve the explanation of this config option. Cc: Andi Kleen Cc: Borislav Petkov Link: http://lkml.kernel.org/n/tip-gUMmysvsbl3mccbyf6olmxqg@git.kernel.org Signed-off-by: Ingo Molnar --- arch/x86/Kconfig | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index c9d2b81..7081958 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -760,15 +760,21 @@ config GART_IOMMU select SWIOTLB depends on X86_64 && PCI && AMD_NB ---help--- - Support for full DMA access of devices with 32bit memory access only - on systems with more than 3GB. This is usually needed for USB, - sound, many IDE/SATA chipsets and some other devices. - Provides a driver for the older AMD Athlon64/Opteron/Turion/Sempron GART - based hardware IOMMU. - Newer systems typically have a better AMD IOMMU. - The code is only active when needed (enough memory and limited - device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified - too. + Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron + GART based hardware IOMMUs. + + The GART supports full DMA access for devices with 32-bit access + limitations, on systems with more than 3 GB. This is usually needed + for USB, sound, many IDE/SATA chipsets and some other devices. + + Newer systems typically have a modern AMD IOMMU, supported via + the CONFIG_AMD_IOMMU=y config option. + + In normal configurations this driver is only active when needed: + there's more than 3 GB of memory and the system contains a + 32-bit limited device. + + If unsure, say Y. config CALGARY_IOMMU bool "IBM Calgary IOMMU support"