[PATCH] x86_64: Improve CONFIG_GART_IOMMU description and make it default y

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 4b8326177c52..660a03a89e66 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -329,12 +329,15 @@ config HPET_EMULATE_RTC
 
 config GART_IOMMU
         bool "IOMMU support"
+        default y
         depends on PCI
         help
-          Support the K8 IOMMU. Needed to run systems with more than 4GB of memory
+          Support the IOMMU. Needed to run systems with more than 3GB of memory
           properly with 32-bit PCI devices that do not support DAC (Double Address
           Cycle). The IOMMU can be turned off at runtime with the iommu=off parameter.
           Normally the kernel will take the right choice by itself.
+          This option includes a driver for the AMD Opteron/Athlon64 IOMMU
+          and a software emulation used on some other systems.
           If unsure, say Y.
 
 # need this always enabled with GART_IOMMU for the VIA workaround