1 files changed, 14 insertions, 8 deletions

diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 02dd39457bcf..7982cbc3bc94 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -152,18 +152,18 @@ config MPSC
           Optimize for Intel Pentium 4 and older Nocona/Dempsey Xeon CPUs
           with Intel Extended Memory 64 Technology(EM64T). For details see
           <http://www.intel.com/technology/64bitextensions/>.
-          Note the the latest Xeons (Xeon 51xx and 53xx) are not based on the
-          Netburst core and shouldn't use this option. You can distingush them
+          Note that the latest Xeons (Xeon 51xx and 53xx) are not based on the
+          Netburst core and shouldn't use this option. You can distinguish them
           using the cpu family field
-          in /proc/cpuinfo. Family 15 is a older Xeon, Family 6 a newer one
-          (this rule only applies to system that support EM64T)
+          in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one
+          (this rule only applies to systems that support EM64T)
 
 config MCORE2
         bool "Intel Core2 / newer Xeon"
         help
           Optimize for Intel Core2 and newer Xeons (51xx)
-          You can distingush the newer Xeons from the older ones using
-          the cpu family field in /proc/cpuinfo. 15 is a older Xeon
+          You can distinguish the newer Xeons from the older ones using
+          the cpu family field in /proc/cpuinfo. 15 is an older Xeon
           (use CONFIG_MPSC then), 6 is a newer one. This rule only
           applies to CPUs that support EM64T.
 
@@ -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