From: Shameer Kolothum Date: Fri, 21 Feb 2025 14:02:25 +0000 (+0000) Subject: KVM: arm64: Specify hypercall ABI for retrieving target implementations X-Git-Tag: v6.15-rc1~195^2~2^2~4^2~5 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=57e5cc9b8a399f85c95b6249ecb423553aad209c;p=thirdparty%2Fkernel%2Flinux.git KVM: arm64: Specify hypercall ABI for retrieving target implementations If the Guest requires migration to multiple targets, these hypercalls will provide a way to retrieve the target CPU implementations from the user space VMM. Subsequent patch will use this to enable the associated errata. Suggested-by: Oliver Upton Suggested-by: Marc Zyngier Reviewed-by: Cornelia Huck Reviewed-by: Sebastian Ott Signed-off-by: Shameer Kolothum Link: https://lore.kernel.org/r/20250221140229.12588-3-shameerali.kolothum.thodi@huawei.com Signed-off-by: Oliver Upton --- diff --git a/Documentation/virt/kvm/arm/hypercalls.rst b/Documentation/virt/kvm/arm/hypercalls.rst index af7bc2c2e0cb4..7400a89aabf88 100644 --- a/Documentation/virt/kvm/arm/hypercalls.rst +++ b/Documentation/virt/kvm/arm/hypercalls.rst @@ -142,3 +142,62 @@ region is equal to the memory protection granule advertised by | | | +---------------------------------------------+ | | | | ``INVALID_PARAMETER (-3)`` | +---------------------+----------+----+---------------------------------------------+ + +``ARM_SMCCC_VENDOR_HYP_KVM_DISCOVER_IMPL_VER_FUNC_ID`` +------------------------------------------------------- +Request the target CPU implementation version information and the number of target +implementations for the Guest VM. + ++---------------------+-------------------------------------------------------------+ +| Presence: | Optional; KVM/ARM64 Guests only | ++---------------------+-------------------------------------------------------------+ +| Calling convention: | HVC64 | ++---------------------+----------+--------------------------------------------------+ +| Function ID: | (uint32) | 0xC6000040 | ++---------------------+----------+--------------------------------------------------+ +| Arguments: | None | ++---------------------+----------+----+---------------------------------------------+ +| Return Values: | (int64) | R0 | ``SUCCESS (0)`` | +| | | +---------------------------------------------+ +| | | | ``NOT_SUPPORTED (-1)`` | +| +----------+----+---------------------------------------------+ +| | (uint64) | R1 | Bits [63:32] Reserved/Must be zero | +| | | +---------------------------------------------+ +| | | | Bits [31:16] Major version | +| | | +---------------------------------------------+ +| | | | Bits [15:0] Minor version | +| +----------+----+---------------------------------------------+ +| | (uint64) | R2 | Number of target implementations | +| +----------+----+---------------------------------------------+ +| | (uint64) | R3 | Reserved / Must be zero | ++---------------------+----------+----+---------------------------------------------+ + +``ARM_SMCCC_VENDOR_HYP_KVM_DISCOVER_IMPL_CPUS_FUNC_ID`` +------------------------------------------------------- + +Request the target CPU implementation information for the Guest VM. The Guest kernel +will use this information to enable the associated errata. + ++---------------------+-------------------------------------------------------------+ +| Presence: | Optional; KVM/ARM64 Guests only | ++---------------------+-------------------------------------------------------------+ +| Calling convention: | HVC64 | ++---------------------+----------+--------------------------------------------------+ +| Function ID: | (uint32) | 0xC6000041 | ++---------------------+----------+----+---------------------------------------------+ +| Arguments: | (uint64) | R1 | selected implementation index | +| +----------+----+---------------------------------------------+ +| | (uint64) | R2 | Reserved / Must be zero | +| +----------+----+---------------------------------------------+ +| | (uint64) | R3 | Reserved / Must be zero | ++---------------------+----------+----+---------------------------------------------+ +| Return Values: | (int64) | R0 | ``SUCCESS (0)`` | +| | | +---------------------------------------------+ +| | | | ``INVALID_PARAMETER (-3)`` | +| +----------+----+---------------------------------------------+ +| | (uint64) | R1 | MIDR_EL1 of the selected implementation | +| +----------+----+---------------------------------------------+ +| | (uint64) | R2 | REVIDR_EL1 of the selected implementation | +| +----------+----+---------------------------------------------+ +| | (uint64) | R3 | AIDR_EL1 of the selected implementation | ++---------------------+----------+----+---------------------------------------------+ diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index 67f6fdf2e7cd8..f19be57540905 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -179,6 +179,9 @@ #define ARM_SMCCC_KVM_FUNC_PKVM_RESV_62 62 #define ARM_SMCCC_KVM_FUNC_PKVM_RESV_63 63 /* End of pKVM hypercall range */ +#define ARM_SMCCC_KVM_FUNC_DISCOVER_IMPL_VER 64 +#define ARM_SMCCC_KVM_FUNC_DISCOVER_IMPL_CPUS 65 + #define ARM_SMCCC_KVM_FUNC_FEATURES_2 127 #define ARM_SMCCC_KVM_NUM_FUNCS 128 @@ -225,6 +228,18 @@ ARM_SMCCC_OWNER_VENDOR_HYP, \ ARM_SMCCC_KVM_FUNC_MMIO_GUARD) +#define ARM_SMCCC_VENDOR_HYP_KVM_DISCOVER_IMPL_VER_FUNC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_64, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + ARM_SMCCC_KVM_FUNC_DISCOVER_IMPL_VER) + +#define ARM_SMCCC_VENDOR_HYP_KVM_DISCOVER_IMPL_CPUS_FUNC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_64, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + ARM_SMCCC_KVM_FUNC_DISCOVER_IMPL_CPUS) + /* ptp_kvm counter type ID */ #define KVM_PTP_VIRT_COUNTER 0 #define KVM_PTP_PHYS_COUNTER 1