Documentation/virt/kvm/devices/vcpu.rst

   1 .. SPDX-License-Identifier: GPL-2.0
   2
   3 ======================
   4 Generic vcpu interface
   5 ======================
   6
   7 The virtual cpu "device" also accepts the ioctls KVM_SET_DEVICE_ATTR,
   8 KVM_GET_DEVICE_ATTR, and KVM_HAS_DEVICE_ATTR. The interface uses the same struct
   9 kvm_device_attr as other devices, but targets VCPU-wide settings and controls.
  10
  11 The groups and attributes per virtual cpu, if any, are architecture specific.
  12
  13 1. GROUP: KVM_ARM_VCPU_PMU_V3_CTRL
  14 ==================================
  15
  16 :Architectures: ARM64
  17
  18 1.1. ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_IRQ
  19 ---------------------------------------
  20
  21 :Parameters: in kvm_device_attr.addr the address for PMU overflow interrupt is a
  22              pointer to an int
  23
  24 Returns:
  25
  26          =======  ========================================================
  27          -EBUSY   The PMU overflow interrupt is already set
  28          -ENXIO   The overflow interrupt not set when attempting to get it
  29          -ENODEV  PMUv3 not supported
  30          -EINVAL  Invalid PMU overflow interrupt number supplied or
  31                   trying to set the IRQ number without using an in-kernel
  32                   irqchip.
  33          =======  ========================================================
  34
  35 A value describing the PMUv3 (Performance Monitor Unit v3) overflow interrupt
  36 number for this vcpu. This interrupt could be a PPI or SPI, but the interrupt
  37 type must be same for each vcpu. As a PPI, the interrupt number is the same for
  38 all vcpus, while as an SPI it must be a separate number per vcpu.
  39
  40 1.2 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_INIT
  41 ---------------------------------------
  42
  43 :Parameters: no additional parameter in kvm_device_attr.addr
  44
  45 Returns:
  46
  47          =======  ======================================================
  48          -ENODEV  PMUv3 not supported or GIC not initialized
  49          -ENXIO   PMUv3 not properly configured or in-kernel irqchip not
  50                   configured as required prior to calling this attribute
  51          -EBUSY   PMUv3 already initialized
  52          =======  ======================================================
  53
  54 Request the initialization of the PMUv3.  If using the PMUv3 with an in-kernel
  55 virtual GIC implementation, this must be done after initializing the in-kernel
  56 irqchip.
  57
  58
  59 2. GROUP: KVM_ARM_VCPU_TIMER_CTRL
  60 =================================
  61
  62 :Architectures: ARM, ARM64
  63
  64 2.1. ATTRIBUTES: KVM_ARM_VCPU_TIMER_IRQ_VTIMER, KVM_ARM_VCPU_TIMER_IRQ_PTIMER
  65 -----------------------------------------------------------------------------
  66
  67 :Parameters: in kvm_device_attr.addr the address for the timer interrupt is a
  68              pointer to an int
  69
  70 Returns:
  71
  72          =======  =================================
  73          -EINVAL  Invalid timer interrupt number
  74          -EBUSY   One or more VCPUs has already run
  75          =======  =================================
  76
  77 A value describing the architected timer interrupt number when connected to an
  78 in-kernel virtual GIC.  These must be a PPI (16 <= intid < 32).  Setting the
  79 attribute overrides the default values (see below).
  80
  81 =============================  ==========================================
  82 KVM_ARM_VCPU_TIMER_IRQ_VTIMER  The EL1 virtual timer intid (default: 27)
  83 KVM_ARM_VCPU_TIMER_IRQ_PTIMER  The EL1 physical timer intid (default: 30)
  84 =============================  ==========================================
  85
  86 Setting the same PPI for different timers will prevent the VCPUs from running.
  87 Setting the interrupt number on a VCPU configures all VCPUs created at that
  88 time to use the number provided for a given timer, overwriting any previously
  89 configured values on other VCPUs.  Userspace should configure the interrupt
  90 numbers on at least one VCPU after creating all VCPUs and before running any
  91 VCPUs.
  92
  93 3. GROUP: KVM_ARM_VCPU_PVTIME_CTRL
  94 ==================================
  95
  96 :Architectures: ARM64
  97
  98 3.1 ATTRIBUTE: KVM_ARM_VCPU_PVTIME_IPA
  99 --------------------------------------
 100
 101 :Parameters: 64-bit base address
 102
 103 Returns:
 104
 105          =======  ======================================
 106          -ENXIO   Stolen time not implemented
 107          -EEXIST  Base address already set for this VCPU
 108          -EINVAL  Base address not 64 byte aligned
 109          =======  ======================================
 110
 111 Specifies the base address of the stolen time structure for this VCPU. The
 112 base address must be 64 byte aligned and exist within a valid guest memory
 113 region. See Documentation/virt/kvm/arm/pvtime.txt for more information
 114 including the layout of the stolen time structure.