GICR_IIDR, Redistributor Implementer Identification Register
The GICR_IIDR characteristics are:
Provides information about the implementer and revision of the Redistributor.
This register is available in all configurations of the GIC. If the GIC implementation supports two Security states, this register is Common.
GICR_IIDR is a 32-bit register.
The GICR_IIDR bit assignments are:
ProductID, bits [31:24]
An IMPLEMENTATION DEFINED product identifier.
Variant, bits [19:16]
An IMPLEMENTATION DEFINED variant number. Typically, this field is used to distinguish product variants, or major revisions of a product.
Revision, bits [15:12]
An IMPLEMENTATION DEFINED revision number. Typically, this field is used to distinguish minor revisions of a product.
Implementer, bits [11:0]
Contains the JEP106 code of the company that implemented the Redistributor:
- Bits [11:8] are the JEP106 continuation code of the implementer. For an Arm implementation, this field is 0x4.
- Bit  is always 0.
- Bits [6:0] are the JEP106 identity code of the implementer. For an Arm implementation, bits [7:0] are therefore 0x3B.
Accessing the GICR_IIDR
GICR_IIDR can be accessed through the memory-mapped interfaces:
This interface is accessible as follows:
- When GICD_CTLR.DS == 0b0 access to this register is RO.
- When IsAccessSecure() access to this register is RO.
- When !IsAccessSecure() access to this register is RO.