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Plic Mapper

The PLIC Mapper defines the register generation and access for a PLIC (Platform Level Interrupt Controller.

PlicMapper.apply

(bus: BusSlaveFactory, mapping: PlicMapping)(gateways : Seq[PlicGateway], targets : Seq[PlicTarget])

args for PlicMapper:

  • bus: bus to which this ctrl is attached

  • mapping: a mapping configuration (see above)

  • gateways: a sequence of PlicGateway (interrupt sources) to generate the bus access control

  • targets: the sequence of PlicTarget (eg. multiple cores) to generate the bus access control

It follows the interface given by riscv: https://github.com/riscv/riscv-plic-spec/blob/master/riscv-plic.adoc

As of now, two memory mappings are available :

PlicMapping.sifive

Follows the SiFive PLIC mapping (eg. E31 core complex Manual ), basically a full fledged PLIC

PlicMapping.light

This mapping generates a lighter PLIC, at the cost of some missing optional features:

  • no reading the intrerrupt’s priority

  • no reading the interrupts’s pending bit (must use the claim/complete mechanism)

  • no reading the target’s threshold

The rest of the registers & logic is generated.