The ERRDEVAFF characteristics are:
For a group that has affinity with a single PE or cluster of PEs, ERRDEVAFF is a copy of MPIDR_EL1 or part of MPIDR_EL1:
For example, if the affinity level is 2 then all of the following are true:
Implementation of this register is OPTIONAL.
This register is present only when RAS is implemented. Otherwise, direct accesses to ERRDEVAFF are RES0.
Present only if a group has affinity with a PE or cluster of PEs, and otherwise RES0.
ERRDEVAFF is a 64-bit register.
The ERRDEVAFF bit assignments are:
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 |
RES0 | Aff3 | ||||||||||||||||||||||||||||||
F0V | U | RES0 | MT | Aff2 | Aff1 | Aff0 | |||||||||||||||||||||||||
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 |
Reserved, RES0.
Affinity level 3. The MPIDR_EL1.Aff3 field, viewed from the highest Exception level of the associated PE or PEs.
Indicates that the ERRDEVAFF.Aff0 field is valid.
F0V | Meaning |
---|---|
0b0 |
ERRDEVAFF.Aff0 is not valid, and the PE affinity level is 1, 2 or 3. |
0b1 |
ERRDEVAFF.Aff0 is valid, and the PE affinity level is 0. |
Uniprocessor. The MPIDR_EL1.U bit viewed from the highest Exception level of the associated PE.
U | Meaning |
---|---|
0b0 |
The PE is part of a multiprocessor system. |
0b1 |
The PE is part of a uniprocessor system. |
If ERRDEVAFF.Aff0 is not valid, this bit is not valid and reads as UNKNOWN.
Reserved, RES0.
Multithreaded. The MPIDR_EL1.MT bit viewed from the highest Exception level of the associated PE.
MT | Meaning |
---|---|
0b0 |
Performance of PEs at the lowest affinity level is largely independent. |
0b1 |
Performance of PEs at the lowest affinity level is very interdependent. |
If ERRDEVAFF.Aff0 is not valid, this bit is not valid and reads as UNKNOWN.
Affinity level 2.
When the PE affinity level is 0, 1, or 2, this field is the MPIDR_EL1.Aff2 field viewed from the highest Exception level of the associated PE or PEs.
When the PE affinity level is 3, this field indicates that ERRDEVAFF.Aff3 field is valid, and the following values are defined:
Aff2 | Meaning |
---|---|
0x80 |
ERRDEVAFF.Aff3 is valid, and the PE affinity level is 3. |
This field reads as 0x80.
All other values are reserved.
Affinity level 1.
When the PE affinity level is 0 or 1, this field is the MPIDR_EL1.Aff1 field viewed from the highest Exception level of the associated PE or PEs.
When the PE affinity level is 2 or 3, this field indicates that ERRDEVAFF.Aff2 is valid, and the following values are defined:
Aff1 | Meaning |
---|---|
0x00 |
ERRDEVAFF.Aff2 is not valid, and the PE affinity level is 3. |
0x80 |
ERRDEVAFF.Aff2 is valid, and the PE affinity level is 2. |
All other values are reserved.
Affinity level 0.
When the PE affinity level is 0, this field is the MPIDR_EL1.Aff0 field viewed from the highest Exception level of the associated PE or PEs.
When the PE affinity level is 1, 2 or 3, this field indicates that ERRDEVAFF.Aff1 is valid, and the following values are defined:
Aff0 | Meaning |
---|---|
0x00 |
ERRDEVAFF.Aff1 is not valid, and the PE affinity level is 2 or 3. |
0x80 |
ERRDEVAFF.Aff1 is valid, and the PE affinity level is 1. |
All other values are reserved.
Component | Offset | Instance |
---|---|---|
RAS | 0xFA8 | ERRDEVAFF |
Access on this interface is RO.
27/03/2019 21:59; e5e4db499bf9867a4b93324c4dbac985d3da9376
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