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| author |  Will Deacon <will@kernel.org>
| 2024-04-23 16:05:35 +0100 |
|---|---|---|
| committer |  Marc Zyngier <maz@kernel.org>
| 2024-05-01 16:48:14 +0100 |
| commit | 4dc8c9de384fb99692d35d2acdfedd5660930dfc (patch) | |
| tree | 8ba9a4bbf96c63143cee714d8fc4decac82dc4db /Documentation/virt | |
| parent | KVM: arm64: Rename firmware pseudo-register documentation file (diff) | |
| download | linux-4dc8c9de384fb99692d35d2acdfedd5660930dfc.tar.gz linux-4dc8c9de384fb99692d35d2acdfedd5660930dfc.tar.bz2 linux-4dc8c9de384fb99692d35d2acdfedd5660930dfc.zip | |
KVM: arm64: Document the KVM/arm64-specific calls in hypercalls.rst
KVM/arm64 makes use of the SMCCC "Vendor Specific Hypervisor Service
Call Range" to expose KVM-specific hypercalls to guests in a
discoverable and extensible fashion.
Document the existence of this interface and the discovery hypercall.
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240423150538.2103045-28-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'Documentation/virt')
| -rw-r--r-- | Documentation/virt/kvm/arm/hypercalls.rst | 46 | ||||
| -rw-r--r-- | Documentation/virt/kvm/arm/index.rst | 1 |
2 files changed, 47 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/arm/hypercalls.rst b/Documentation/virt/kvm/arm/hypercalls.rst new file mode 100644 index 000000000000..17be111f493f --- /dev/null +++ b/Documentation/virt/kvm/arm/hypercalls.rst @@ -0,0 +1,46 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=============================================== +KVM/arm64-specific hypercalls exposed to guests +=============================================== + +This file documents the KVM/arm64-specific hypercalls which may be +exposed by KVM/arm64 to guest operating systems. These hypercalls are +issued using the HVC instruction according to version 1.1 of the Arm SMC +Calling Convention (DEN0028/C): + +https://developer.arm.com/docs/den0028/c + +All KVM/arm64-specific hypercalls are allocated within the "Vendor +Specific Hypervisor Service Call" range with a UID of +``28b46fb6-2ec5-11e9-a9ca-4b564d003a74``. This UID should be queried by the +guest using the standard "Call UID" function for the service range in +order to determine that the KVM/arm64-specific hypercalls are available. + +``ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID`` +--------------------------------------------- + +Provides a discovery mechanism for other KVM/arm64 hypercalls. + ++---------------------+-------------------------------------------------------------+ +| Presence: | Mandatory for the KVM/arm64 UID | ++---------------------+-------------------------------------------------------------+ +| Calling convention: | HVC32 | ++---------------------+----------+--------------------------------------------------+ +| Function ID: | (uint32) | 0x86000000 | ++---------------------+----------+--------------------------------------------------+ +| Arguments: | None | ++---------------------+----------+----+---------------------------------------------+ +| Return Values: | (uint32) | R0 | Bitmap of available function numbers 0-31 | +| +----------+----+---------------------------------------------+ +| | (uint32) | R1 | Bitmap of available function numbers 32-63 | +| +----------+----+---------------------------------------------+ +| | (uint32) | R2 | Bitmap of available function numbers 64-95 | +| +----------+----+---------------------------------------------+ +| | (uint32) | R3 | Bitmap of available function numbers 96-127 | ++---------------------+----------+----+---------------------------------------------+ + +``ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID`` +---------------------------------------- + +See ptp_kvm.rst diff --git a/Documentation/virt/kvm/arm/index.rst b/Documentation/virt/kvm/arm/index.rst index d28d65122290..ec09881de4cf 100644 --- a/Documentation/virt/kvm/arm/index.rst +++ b/Documentation/virt/kvm/arm/index.rst @@ -9,6 +9,7 @@ ARM fw-pseudo-registers hyp-abi + hypercalls pvtime ptp_kvm vcpu-features |