Intel IOMMU: Intel IOMMU driver

Actual intel IOMMU driver.  Hardware spec can be found at:
http://www.intel.com/technology/virtualization

This driver sets X86_64 'dma_ops', so hook into standard DMA APIs.  In this
way, PCI driver will get virtual DMA address.  This change is transparent to
PCI drivers.

[akpm@linux-foundation.org: remove unneeded cast]
[akpm@linux-foundation.org: build fix]
[bunk@stusta.de: fix duplicate CONFIG_DMAR Makefile line]
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 6accd360da73..8157417724a8 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -772,6 +772,16 @@ and is between 256 and 4096 characters. It is defined in the file
 
         inttest=        [IA64]
 
+        intel_iommu=    [DMAR] Intel IOMMU driver (DMAR) option
+                off
+                        Disable intel iommu driver.
+                igfx_off [Default Off]
+                        By default, gfx is mapped as normal device. If a gfx
+                        device has a dedicated DMAR unit, the DMAR unit is
+                        bypassed by not enabling DMAR with this option. In
+                        this case, gfx device will use physical address for
+                        DMA.
+
         io7=            [HW] IO7 for Marvel based alpha systems
                         See comment before marvel_specify_io7 in
                         arch/alpha/kernel/core_marvel.c.