iommu/amd: Detect and enable guest vAPIC support
This patch introduces a new IOMMU driver parameter, amd_iommu_guest_ir,
which can be used to specify different interrupt remapping mode for
passthrough devices to VM guest:
* legacy: Legacy interrupt remapping (w/ 32-bit IRTE)
* vapic : Guest vAPIC interrupt remapping (w/ GA mode 128-bit IRTE)
Note that in vapic mode, it can also supports legacy interrupt remapping
for non-passthrough devices with the 128-bit IRTE.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 46c030a..748ef7b 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -460,6 +460,15 @@
driver will print ACPI tables for AMD IOMMU during
IOMMU initialization.
+ amd_iommu_intr= [HW,X86-64]
+ Specifies one of the following AMD IOMMU interrupt
+ remapping modes:
+ legacy - Use legacy interrupt remapping mode.
+ vapic - Use virtual APIC mode, which allows IOMMU
+ to inject interrupts directly into guest.
+ This mode requires kvm-amd.avic=1.
+ (Default when IOMMU HW support is present.)
+
amijoy.map= [HW,JOY] Amiga joystick support
Map of devices attached to JOY0DAT and JOY1DAT
Format: <a>,<b>
