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EDDEVAFF1

EDDEVAFF1, External Debug Device Affinity register 1

The EDDEVAFF1 characteristics are:

Purpose

Copy of the high half of the PE MPIDR_EL1 register that allows a debugger to determine which PE in a multiprocessor system the external debug component relates to.

Configuration

When FEAT_DoPD is implemented, EDDEVAFF1 is in the Core power domain. Otherwise, EDDEVAFF1 is in the Debug power domain.

Attributes

EDDEVAFF1 is a 32-bit register.

Field descriptions

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
RES0																								Aff3

Bits [31:8]

Reserved, RES0.

Aff3, bits [7:0]

Affinity level 3. See the description of EDDEVAFF0.Aff0 for more information.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Accessing EDDEVAFF1

EDDEVAFF1 can be accessed through the external debug interface:

Component	Offset	Instance
Debug	0xFAC	EDDEVAFF1

Accessible as follows:

When FEAT_DoPD is implemented and !IsCorePowered(), accesses to this register generate an error response.
Otherwise, accesses to this register are RO.

2026-03-26 20:27:25, 2026-03_rel