diff options
Diffstat (limited to 'Documentation/virt/kvm/devices/vcpu.txt')
| -rw-r--r-- | Documentation/virt/kvm/devices/vcpu.txt | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/devices/vcpu.txt b/Documentation/virt/kvm/devices/vcpu.txt new file mode 100644 index 000000000000..2b5dab16c4f2 --- /dev/null +++ b/Documentation/virt/kvm/devices/vcpu.txt @@ -0,0 +1,62 @@ +Generic vcpu interface +==================================== + +The virtual cpu "device" also accepts the ioctls KVM_SET_DEVICE_ATTR, +KVM_GET_DEVICE_ATTR, and KVM_HAS_DEVICE_ATTR. The interface uses the same struct +kvm_device_attr as other devices, but targets VCPU-wide settings and controls. + +The groups and attributes per virtual cpu, if any, are architecture specific. + +1. GROUP: KVM_ARM_VCPU_PMU_V3_CTRL +Architectures: ARM64 + +1.1. ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_IRQ +Parameters: in kvm_device_attr.addr the address for PMU overflow interrupt is a + pointer to an int +Returns: -EBUSY: The PMU overflow interrupt is already set + -ENXIO: The overflow interrupt not set when attempting to get it + -ENODEV: PMUv3 not supported + -EINVAL: Invalid PMU overflow interrupt number supplied or + trying to set the IRQ number without using an in-kernel + irqchip. + +A value describing the PMUv3 (Performance Monitor Unit v3) overflow interrupt +number for this vcpu. This interrupt could be a PPI or SPI, but the interrupt +type must be same for each vcpu. As a PPI, the interrupt number is the same for +all vcpus, while as an SPI it must be a separate number per vcpu. + +1.2 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_INIT +Parameters: no additional parameter in kvm_device_attr.addr +Returns: -ENODEV: PMUv3 not supported or GIC not initialized + -ENXIO: PMUv3 not properly configured or in-kernel irqchip not + configured as required prior to calling this attribute + -EBUSY: PMUv3 already initialized + +Request the initialization of the PMUv3. If using the PMUv3 with an in-kernel +virtual GIC implementation, this must be done after initializing the in-kernel +irqchip. + + +2. GROUP: KVM_ARM_VCPU_TIMER_CTRL +Architectures: ARM,ARM64 + +2.1. ATTRIBUTE: KVM_ARM_VCPU_TIMER_IRQ_VTIMER +2.2. ATTRIBUTE: KVM_ARM_VCPU_TIMER_IRQ_PTIMER +Parameters: in kvm_device_attr.addr the address for the timer interrupt is a + pointer to an int +Returns: -EINVAL: Invalid timer interrupt number + -EBUSY: One or more VCPUs has already run + +A value describing the architected timer interrupt number when connected to an +in-kernel virtual GIC. These must be a PPI (16 <= intid < 32). Setting the +attribute overrides the default values (see below). + +KVM_ARM_VCPU_TIMER_IRQ_VTIMER: The EL1 virtual timer intid (default: 27) +KVM_ARM_VCPU_TIMER_IRQ_PTIMER: The EL1 physical timer intid (default: 30) + +Setting the same PPI for different timers will prevent the VCPUs from running. +Setting the interrupt number on a VCPU configures all VCPUs created at that +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. |