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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-04-10 15:21:55 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-04-10 15:21:55 +0200
commitf78a8236c6502760705399dfa42e22ab11aa1e6b (patch)
treed965f09daff0d531c63e35c764e7061f9c43afe7 /Documentation/virtual/kvm/devices/arm-vgic.txt
parent6cb3d05f3030deed157c9bbada5c58e7ee0f5172 (diff)
parent39da7c509acff13fc8cb12ec1bb20337c988ed36 (diff)
Merge 4.11-rc6 into staging-next
We want the staging and iio fixes in here to handle merging easier. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/virtual/kvm/devices/arm-vgic.txt')
-rw-r--r--Documentation/virtual/kvm/devices/arm-vgic.txt6
1 files changed, 6 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt
index 76e61c883347..b2f60ca8b60c 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic.txt
@@ -83,6 +83,12 @@ Groups:
Bits for undefined preemption levels are RAZ/WI.
+ For historical reasons and to provide ABI compatibility with userspace we
+ export the GICC_PMR register in the format of the GICH_VMCR.VMPriMask
+ field in the lower 5 bits of a word, meaning that userspace must always
+ use the lower 5 bits to communicate with the KVM device and must shift the
+ value left by 3 places to obtain the actual priority mask level.
+
Limitations:
- Priorities are not implemented, and registers are RAZ/WI
- Currently only implemented for KVM_DEV_TYPE_ARM_VGIC_V2.