Advanced Configuration and Power Interface Specification

Advanced Configuration and Power Interface Specification
to the same number of contiguous GSIVs. Therefore, each used interrupt input must be mapped to
the global system interrupt value used by ACPI for that input. This mapping is provided by the GIC
Distributor structure, by setting the base GSIV for the GIC Distributor.
The format of the GIC Distributor structure is listed in Table 5-63.
Table 5-63 GIC Distributor Structure
Field
Byte
Length
Byte
Offset
Description
Type 1 0 0xC GIC Distributor structure
Length 1 1 24
Reserved 2 2 Reserved - Must be zero
GIC ID 4 4 This GIC Distributor’s hardware ID
Physical Base
Address
8 8 The 64-bit physical address for this Distributor
System Vector
Base
4 16 The global system interrupt number where this GIC Distributor’s
interrupt inputs start.
GIC version 1 20 0x00: No GIC version is specified, fall back to hardware discovery
for GIC version
0x01: GICv1
0x02: GICv2
0x03: GICv3
0x04: GICv4
0x05-0xFF, Reserved for future use.
Reserved 3 21 Must be zero
5.2.12.16 GIC MSI Frame Structure
Each GICv2m MSI frame consists of a 4k page which includes registers to generate message
signaled interrupts to an associated GIC distributor. The frame also includes registers to discover the
set of distributor lines which may be signaled by MSIs from that frame. A system may have multiple
MSI frames, and separate frames may be defined for secure and non-secure access. This structure
must only be used to describe non-secure MSI frames.
The format of the GIC MSI Frame Structure is listed in Table 5-64.
Table 5-64 GIC MSI Structure
Field
Byte
Length
Byte
Offset
Description
Type 1 0 0xD GIC MSI structure
Length 1 1 24
Reserved 2 2 Reserved - Must be zero
GIC MSI Frame ID 4 4 GIC MSI Frame ID. In a system with multiple GIC MSI frames, this
value must be unique to each one.
Physical Base
Address
8 8 The 64-bit physical address for this MSI Frame
152 April, 2015 Version 6.0