[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>

diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 4b8326177c52fba07bc4d9399d186da6609b946a..660a03a89e6663bf7f04bd83c163c441210e8dc1 100644 (file)
--- 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