diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2018-01-21 16:42:56 +0000 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2018-04-20 16:32:23 +0100 |
| commit | 85bd0ba1ff9875798fad94218b627ea9f768f3c3 (patch) | |
| tree | 7a1d8741a980a8d8d0a235c1784b2121634a9265 /Documentation/virtual/kvm/api.txt | |
| parent | bf9a41377d14f565764022470e14aae72559589a (diff) | |
arm/arm64: KVM: Add PSCI version selection API
Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1
or 1.0 to a guest, defaulting to the latest version of the PSCI
implementation that is compatible with the requested version. This is
no different from doing a firmware upgrade on KVM.
But in order to give a chance to hypothetical badly implemented guests
that would have a fit by discovering something other than PSCI 0.2,
let's provide a new API that allows userspace to pick one particular
version of the API.
This is implemented as a new class of "firmware" registers, where
we expose the PSCI version. This allows the PSCI version to be
save/restored as part of a guest migration, and also set to
any supported version if the guest requires it.
Cc: stable@vger.kernel.org #4.16
Reviewed-by: Christoffer Dall <cdall@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'Documentation/virtual/kvm/api.txt')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 1c7958b57fe9..758bf403a169 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1960,6 +1960,9 @@ ARM 32-bit VFP control registers have the following id bit patterns: ARM 64-bit FP registers have the following id bit patterns: 0x4030 0000 0012 0 <regno:12> +ARM firmware pseudo-registers have the following bit pattern: + 0x4030 0000 0014 <regno:16> + arm64 registers are mapped using the lower 32 bits. The upper 16 of that is the register group type, or coprocessor number: @@ -1976,6 +1979,9 @@ arm64 CCSIDR registers are demultiplexed by CSSELR value: arm64 system registers have the following id bit patterns: 0x6030 0000 0013 <op0:2> <op1:3> <crn:4> <crm:4> <op2:3> +arm64 firmware pseudo-registers have the following bit pattern: + 0x6030 0000 0014 <regno:16> + MIPS registers are mapped using the lower 32 bits. The upper 16 of that is the register group type: @@ -2510,7 +2516,8 @@ Possible features: and execute guest code when KVM_RUN is called. - KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode. Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only). - - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 for the CPU. + - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 (or a future revision + backward compatible with v0.2) for the CPU. Depends on KVM_CAP_ARM_PSCI_0_2. - KVM_ARM_VCPU_PMU_V3: Emulate PMUv3 for the CPU. Depends on KVM_CAP_ARM_PMU_V3. |