PMDEVAFF

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PMDEVAFF, Performance Monitors Device Affinity register

Purpose

Copy of the PE MPIDR_EL1 register that allows a debugger to determine which PE in a multiprocessor system the Performance Monitor component relates to.

Configuration

If FEAT_DoPD is implemented, this register is in the Core power domain. If FEAT_DoPD is not implemented, this register is in the Debug power domain.

Attributes

Field descriptions

Bits [63:40]

Aff3, bits [39:32]

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

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Bit [31]

U, bit [30]

Indicates a Uniprocessor system, as distinct from PE 0 in a multiprocessor system.

The value of this field is an IMPLEMENTATION DEFINED choice of:

U	Meaning
0b0	Processor is part of a multiprocessor system.
0b1	Processor is part of a uniprocessor system.

Access to this field is RO.

Bits [29:25]

MT, bit [24]

Indicates whether the lowest level of affinity consists of logical PEs that are implemented using an interdependent approach, such as multithreading. See the description of Aff0 for more information about affinity levels.

The value of this field is an IMPLEMENTATION DEFINED choice of:

MT	Meaning
0b0	Performance of PEs with different affinity level 0 values, and the same values for affinity level 1 and higher, is largely independent.
0b1	Performance of PEs with different affinity level 0 values, and the same values for affinity level 1 and higher, is very interdependent.

Note

This field does not indicate that multithreading is implemented and does not indicate that PEs with different affinity level 0 values, and the same values for affinity level 1 and higher are implemented.

Access to this field is RO.

Aff2, bits [23:16]

Affinity level 2. See the description of Aff0 for more information.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Aff1, bits [15:8]

Affinity level 1. See the description of Aff0 for more information.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Aff0, bits [7:0]

Affinity level 0. The value of the MPIDR.{Aff2, Aff1, Aff0} or MPIDR_EL1.{Aff3, Aff2, Aff1, Aff0} set of fields of each PE must be unique within the system as a whole.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Accessing PMDEVAFF

If FEAT_PMUv3_EXT32 is implemented, then the same content is present in the same locations, and can be accessed using PMDEVAFF0[31:0] and PMDEVAFF1[31:0].

Accesses to this register use the following encodings:

Accessible at offset 0xFA8 from PMU

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

63	62	61	60	59	58	57	56	55	54	53	52	51	50	49	48	47	46	45	44	43	42	41	40	39	38	37	36	35	34	33	32
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
RAO/WI	U	RES0					MT	Aff2								Aff1								Aff0