From 5558870bfbcca10cfc7b13ab866687012ea3c9af Mon Sep 17 00:00:00 2001 From: Karsten Weiss Date: Tue, 13 Feb 2007 13:26:21 +0100 Subject: [PATCH] x86-64: improved iommu documentation - add SWIOTLB config help text - mention Documentation/x86_64/boot-options.txt in Documentation/kernel-parameters.txt - remove the duplication of the iommu kernel parameter documentation. - Better explanation of some of the iommu kernel parameter options. - "32MB< Signed-off-by: Andi Kleen Acked-by: Muli Ben-Yehuda Cc: Andi Kleen Signed-off-by: Andrew Morton --- arch/x86_64/Kconfig | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch/x86_64/Kconfig') diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig index 02dd39457bc..a55382a1bb4 100644 --- a/arch/x86_64/Kconfig +++ b/arch/x86_64/Kconfig @@ -458,8 +458,8 @@ config IOMMU 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 AMD Athlon64/Opteron/Turion/Sempron GART - based IOMMU and a software bounce buffer based IOMMU used on Intel - systems and as fallback. + based hardware IOMMU and a software bounce buffer based IOMMU used + on Intel systems and as fallback. The code is only active when needed (enough memory and limited device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified too. @@ -496,6 +496,12 @@ config CALGARY_IOMMU_ENABLED_BY_DEFAULT # need this always selected by IOMMU for the VIA workaround config SWIOTLB bool + help + Support for software bounce buffers used on x86-64 systems + which don't have a hardware IOMMU (e.g. the current generation + of Intel's x86-64 CPUs). Using this PCI devices which can only + access 32-bits of memory can be used on systems with more than + 3 GB of memory. If unsure, say Y. config X86_MCE bool "Machine check support" if EMBEDDED -- cgit