Arm GIC version 2 systems that support Message Signalled Interrupts
implement GICv2m MSI frame(s). Each GICv2m MSI frame consists of a
4k page which includes registers to generate message signalled
interrupts to an associated GIC distributor. The frame also includes
registers to discover the set of distributor lines which may be
signalled by MSIs from that frame. A system may have multiple MSI
frames, and separate frames may be defined for secure and non-secure
access.
A MSI Frame structure is part of the Multiple APIC Description Table
(MADT) and must only be used to describe non-secure MSI frames.
The MSI Frame information is described in the platform Device Tree,
the bindings for which can be found at:
- linux/Documentation/devicetree/bindings/interrupt-controller/
arm,gic.yaml
- linux/Documentation/devicetree/bindings/interrupt-controller/
arm,gic-v3.yaml
The FdtHwInfoParser implements a MSI Frame Parser that parses
the platform Device Tree to create CM_ARM_GIC_MSI_FRAME_INFO
objects which are encapsulated in a Configuration Manager
descriptor object and added to the platform information
repository.
The platform Configuration Manager can then utilise this
information when generating the MADT table.
Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Pierre Gondois