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| author | Steven Price <steven.price@arm.com> | 2019-10-21 16:28:14 +0100 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2019-10-21 19:20:25 +0100 |
| commit | 6a7458485b390f48e481fcd4a0b20e6c5c843d2e (patch) | |
| tree | ec921843fb5a9d544d7dbecbd34bb28f9807a135 /Documentation/virt/kvm/devices | |
| parent | dcac930e9901d765234bc15004db4f7d4416db71 (diff) | |
KVM: arm64: Document PV-time interface
Introduce a paravirtualization interface for KVM/arm64 based on the
"Arm Paravirtualized Time for Arm-Base Systems" specification DEN 0057A.
This only adds the details about "Stolen Time" as the details of "Live
Physical Time" have not been fully agreed.
User space can specify a reserved area of memory for the guest and
inform KVM to populate the memory with information on time that the host
kernel has stolen from the guest.
A hypercall interface is provided for the guest to interrogate the
hypervisor's support for this interface and the location of the shared
memory structures.
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'Documentation/virt/kvm/devices')
| -rw-r--r-- | Documentation/virt/kvm/devices/vcpu.txt | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/devices/vcpu.txt b/Documentation/virt/kvm/devices/vcpu.txt index 2b5dab16c4f2..6f3bd64a05b0 100644 --- a/Documentation/virt/kvm/devices/vcpu.txt +++ b/Documentation/virt/kvm/devices/vcpu.txt @@ -60,3 +60,17 @@ time to use the number provided for a given timer, overwriting any previously configured values on other VCPUs. Userspace should configure the interrupt numbers on at least one VCPU after creating all VCPUs and before running any VCPUs. + +3. GROUP: KVM_ARM_VCPU_PVTIME_CTRL +Architectures: ARM64 + +3.1 ATTRIBUTE: KVM_ARM_VCPU_PVTIME_IPA +Parameters: 64-bit base address +Returns: -ENXIO: Stolen time not implemented + -EEXIST: Base address already set for this VCPU + -EINVAL: Base address not 64 byte aligned + +Specifies the base address of the stolen time structure for this VCPU. The +base address must be 64 byte aligned and exist within a valid guest memory +region. See Documentation/virt/kvm/arm/pvtime.txt for more information +including the layout of the stolen time structure. |