[linux-2.6-block.git] / Documentation / virtual / kvm / devices / arm-vgic-its.txt

ARM Virtual Interrupt Translation Service (ITS)
===============================================

Device types supported:
  KVM_DEV_TYPE_ARM_VGIC_ITS    ARM Interrupt Translation Service Controller

The ITS allows MSI(-X) interrupts to be injected into guests. This extension is
optional.  Creating a virtual ITS controller also requires a host GICv3 (see
arm-vgic-v3.txt), but does not depend on having physical ITS controllers.

There can be multiple ITS controllers per guest, each of them has to have
a separate, non-overlapping MMIO region.


Groups:
  KVM_DEV_ARM_VGIC_GRP_ADDR
  Attributes:
    KVM_VGIC_ITS_ADDR_TYPE (rw, 64-bit)
      Base address in the guest physical address space of the GICv3 ITS
      control register frame.
      This address needs to be 64K aligned and the region covers 128K.
  Errors:
    -E2BIG:  Address outside of addressable IPA range
    -EINVAL: Incorrectly aligned address
    -EEXIST: Address already configured
    -EFAULT: Invalid user pointer for attr->addr.
    -ENODEV: Incorrect attribute or the ITS is not supported.


  KVM_DEV_ARM_VGIC_GRP_CTRL
  Attributes:
    KVM_DEV_ARM_VGIC_CTRL_INIT
      request the initialization of the ITS, no additional parameter in
      kvm_device_attr.addr.
  Errors:
    -ENXIO:  ITS not properly configured as required prior to setting
             this attribute
    -ENOMEM: Memory shortage when allocating ITS internal data
Commit	Line	Data
71484802 CD	1	ARM Virtual Interrupt Translation Service (ITS)
	2	===============================================
	3
	4	Device types supported:
	5	KVM_DEV_TYPE_ARM_VGIC_ITS ARM Interrupt Translation Service Controller
	6
	7	The ITS allows MSI(-X) interrupts to be injected into guests. This extension is
	8	optional. Creating a virtual ITS controller also requires a host GICv3 (see
	9	arm-vgic-v3.txt), but does not depend on having physical ITS controllers.
	10
	11	There can be multiple ITS controllers per guest, each of them has to have
	12	a separate, non-overlapping MMIO region.
	13
	14
	15	Groups:
	16	KVM_DEV_ARM_VGIC_GRP_ADDR
	17	Attributes:
	18	KVM_VGIC_ITS_ADDR_TYPE (rw, 64-bit)
	19	Base address in the guest physical address space of the GICv3 ITS
	20	control register frame.
	21	This address needs to be 64K aligned and the region covers 128K.
	22	Errors:
	23	-E2BIG: Address outside of addressable IPA range
	24	-EINVAL: Incorrectly aligned address
	25	-EEXIST: Address already configured
	26	-EFAULT: Invalid user pointer for attr->addr.
	27	-ENODEV: Incorrect attribute or the ITS is not supported.
	28
	29
	30	KVM_DEV_ARM_VGIC_GRP_CTRL
	31	Attributes:
	32	KVM_DEV_ARM_VGIC_CTRL_INIT
	33	request the initialization of the ITS, no additional parameter in
	34	kvm_device_attr.addr.
	35	Errors:
	36	-ENXIO: ITS not properly configured as required prior to setting
	37	this attribute
	38	-ENOMEM: Memory shortage when allocating ITS internal data