Multi-Processor Interrupt Controller (MPIC)
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Multi-Processor Interrupt Controller (MPIC)
The MPIC is a multi-processor structured intelligent interrupt controller.

MPIC Features:

MPIC programming model
Supports two processors
Supports 16 external interrupts
Supports 15 programmable Interrupt & Processor Task priority
levels
Supports the connection of an external 8259 for ISA/AT
compatibility
Distributed interrupt delivery for external I/O interrupts
Direct/Multicast interrupt delivery for Interp rocessor and timer
interrupts
Four Interprocessor Interrupt sources
Four timers
Processor initialization control

Architecture

The PCI Slave of the PHB implements two address decoders for placing
the MPIC registers in PCI IO or PCI Memory space. Access to these
registers requires PPC and PCI bus mastership. These accesses include
interrupt and timer initialization and interrupt vector reads.
The MPIC receives interrupt inputs from 16 external sources, four
interprocessor sources, four timer sources, and one Hawk internal error
interrupt source. The externally sourced interrupts 1 through 15 have two
modes of activation; low level or active high positive edge. External
interrupt 0 can be either level or edge activated with either polarity. The
Hawk internal error interrupt request is an ac ti ve low level sensitive
interrupt. The Interprocessor and timers in terrupts are event activated.