diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 8 | ||||
| -rw-r--r-- | Documentation/virtual/kvm/devices/mpic.txt | 3 | ||||
| -rw-r--r-- | Documentation/virtual/kvm/devices/xics.txt | 66 |
3 files changed, 74 insertions, 3 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 59fd9e6a5366..5f91eda91647 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2772,3 +2772,11 @@ Parameters: args[0] is the MPIC device fd args[1] is the MPIC CPU number for this vcpu This capability connects the vcpu to an in-kernel MPIC device. + +6.7 KVM_CAP_IRQ_XICS + +Architectures: ppc +Parameters: args[0] is the XICS device fd + args[1] is the XICS CPU number (server ID) for this vcpu + +This capability connects the vcpu to an in-kernel XICS device. diff --git a/Documentation/virtual/kvm/devices/mpic.txt b/Documentation/virtual/kvm/devices/mpic.txt index ad0ac778f20a..8257397adc3c 100644 --- a/Documentation/virtual/kvm/devices/mpic.txt +++ b/Documentation/virtual/kvm/devices/mpic.txt @@ -50,7 +50,4 @@ IRQ Routing: regard to any subdivisions in chip documentation such as "internal" or "external" interrupts. - Default routes are established for these pins, with the GSI being equal - to the pin number. - Access to non-SRC interrupts is not implemented through IRQ routing mechanisms. diff --git a/Documentation/virtual/kvm/devices/xics.txt b/Documentation/virtual/kvm/devices/xics.txt new file mode 100644 index 000000000000..42864935ac5d --- /dev/null +++ b/Documentation/virtual/kvm/devices/xics.txt @@ -0,0 +1,66 @@ +XICS interrupt controller + +Device type supported: KVM_DEV_TYPE_XICS + +Groups: + KVM_DEV_XICS_SOURCES + Attributes: One per interrupt source, indexed by the source number. + +This device emulates the XICS (eXternal Interrupt Controller +Specification) defined in PAPR. The XICS has a set of interrupt +sources, each identified by a 20-bit source number, and a set of +Interrupt Control Presentation (ICP) entities, also called "servers", +each associated with a virtual CPU. + +The ICP entities are created by enabling the KVM_CAP_IRQ_ARCH +capability for each vcpu, specifying KVM_CAP_IRQ_XICS in args[0] and +the interrupt server number (i.e. the vcpu number from the XICS's +point of view) in args[1] of the kvm_enable_cap struct. Each ICP has +64 bits of state which can be read and written using the +KVM_GET_ONE_REG and KVM_SET_ONE_REG ioctls on the vcpu. The 64 bit +state word has the following bitfields, starting at the +least-significant end of the word: + +* Unused, 16 bits + +* Pending interrupt priority, 8 bits + Zero is the highest priority, 255 means no interrupt is pending. + +* Pending IPI (inter-processor interrupt) priority, 8 bits + Zero is the highest priority, 255 means no IPI is pending. + +* Pending interrupt source number, 24 bits + Zero means no interrupt pending, 2 means an IPI is pending + +* Current processor priority, 8 bits + Zero is the highest priority, meaning no interrupts can be + delivered, and 255 is the lowest priority. + +Each source has 64 bits of state that can be read and written using +the KVM_GET_DEVICE_ATTR and KVM_SET_DEVICE_ATTR ioctls, specifying the +KVM_DEV_XICS_SOURCES attribute group, with the attribute number being +the interrupt source number. The 64 bit state word has the following +bitfields, starting from the least-significant end of the word: + +* Destination (server number), 32 bits + This specifies where the interrupt should be sent, and is the + interrupt server number specified for the destination vcpu. + +* Priority, 8 bits + This is the priority specified for this interrupt source, where 0 is + the highest priority and 255 is the lowest. An interrupt with a + priority of 255 will never be delivered. + +* Level sensitive flag, 1 bit + This bit is 1 for a level-sensitive interrupt source, or 0 for + edge-sensitive (or MSI). + +* Masked flag, 1 bit + This bit is set to 1 if the interrupt is masked (cannot be delivered + regardless of its priority), for example by the ibm,int-off RTAS + call, or 0 if it is not masked. + +* Pending flag, 1 bit + This bit is 1 if the source has a pending interrupt, otherwise 0. + +Only one XICS instance may be created per VM. |