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| author | Marc Zyngier <maz@kernel.org> | 2021-04-13 16:41:22 +0200 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-04-13 16:41:22 +0200 |
| commit | d8f37d291cd764ee966014ea2768709268d04abb (patch) | |
| tree | 2b6098d67359e8ca053d56f43f7cc12cfa0638f1 /Documentation/virt | |
| parent | Merge branch 'kvm-arm64/nvhe-wxn' into kvmarm-master/next (diff) | |
| parent | KVM: arm64: Fix table format for PTP documentation (diff) | |
| download | linux-d8f37d291cd764ee966014ea2768709268d04abb.tar.xz linux-d8f37d291cd764ee966014ea2768709268d04abb.zip | |
Merge branch 'kvm-arm64/ptp' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'Documentation/virt')
| -rw-r--r-- | Documentation/virt/kvm/api.rst | 10 | ||||
| -rw-r--r-- | Documentation/virt/kvm/arm/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/virt/kvm/arm/ptp_kvm.rst | 25 |
3 files changed, 36 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index b38f77bb74ae..3f210953c135 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -6737,3 +6737,13 @@ vcpu_info is set. The KVM_XEN_HVM_CONFIG_RUNSTATE flag indicates that the runstate-related features KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR/_CURRENT/_DATA/_ADJUST are supported by the KVM_XEN_VCPU_SET_ATTR/KVM_XEN_VCPU_GET_ATTR ioctls. + +8.31 KVM_CAP_PTP_KVM +-------------------- + +:Architectures: arm64 + +This capability indicates that the KVM virtual PTP service is +supported in the host. A VMM can check whether the service is +available to the guest on migration. + diff --git a/Documentation/virt/kvm/arm/index.rst b/Documentation/virt/kvm/arm/index.rst index 3e2b2aba90fc..78a9b670aafe 100644 --- a/Documentation/virt/kvm/arm/index.rst +++ b/Documentation/virt/kvm/arm/index.rst @@ -10,3 +10,4 @@ ARM hyp-abi psci pvtime + ptp_kvm diff --git a/Documentation/virt/kvm/arm/ptp_kvm.rst b/Documentation/virt/kvm/arm/ptp_kvm.rst new file mode 100644 index 000000000000..5d2bc4558b9d --- /dev/null +++ b/Documentation/virt/kvm/arm/ptp_kvm.rst @@ -0,0 +1,25 @@ +.. SPDX-License-Identifier: GPL-2.0 + +PTP_KVM support for arm/arm64 +============================= + +PTP_KVM is used for high precision time sync between host and guests. +It relies on transferring the wall clock and counter value from the +host to the guest using a KVM-specific hypercall. + +* ARM_SMCCC_HYP_KVM_PTP_FUNC_ID: 0x86000001 + +This hypercall uses the SMC32/HVC32 calling convention: + +ARM_SMCCC_HYP_KVM_PTP_FUNC_ID + ============== ======== ===================================== + Function ID: (uint32) 0x86000001 + Arguments: (uint32) KVM_PTP_VIRT_COUNTER(0) + KVM_PTP_PHYS_COUNTER(1) + Return Values: (int32) NOT_SUPPORTED(-1) on error, or + (uint32) Upper 32 bits of wall clock time (r0) + (uint32) Lower 32 bits of wall clock time (r1) + (uint32) Upper 32 bits of counter (r2) + (uint32) Lower 32 bits of counter (r3) + Endianness: No Restrictions. + ============== ======== ===================================== |