The EDDFR characteristics are:
Provides top level information about the debug system.
Debuggers must use EDDEVARCH to determine the Debug architecture version.
For general information about the interpretation of the ID registers, see 'Principles of the ID scheme for fields in ID registers'.
It is IMPLEMENTATION DEFINED whether EDDFR is implemented in the Core power domain or in the Debug power domain.
EDDFR is a 64-bit register.
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 |
UNKNOWN | ExtTrcBuff | UNKNOWN | TraceFilt | UNKNOWN | |||||||||||||||||||||||||||
CTX_CMPs | SEBEP | WRPs | PMSS | BRPs | PMUVer | TraceVer | UNKNOWN |
Reserved, UNKNOWN.
Trace Buffer External Mode Extension.
ExtTrcBuff | Meaning |
---|---|
0b0000 |
Trace Buffer Extension not implemented or Trace Buffer External Mode not implemented. |
0b0001 |
Trace Buffer Extension implemented and Trace Buffer External Mode implemented. |
All other values are reserved.
FEAT_TRBE_EXT implements the functionality identified by the value 0b0001.
Reserved, UNKNOWN.
Armv8.4 Self-hosted Trace Extension version. Defined values are:
TraceFilt | Meaning |
---|---|
0b0000 |
Armv8.4 Self-hosted Trace Extension is not implemented. |
0b0001 |
Armv8.4 Self-hosted Trace Extension is implemented. |
All other values are reserved.
FEAT_TRF implements the functionality added by 0b0001.
From Armv8.4, the permitted values are 0b0000 and 0b0001.
Reserved, UNKNOWN.
Number of breakpoints that are context-aware, minus 1.
If FEAT_Debugv8p9 is implemented and 16 or more breakpoints that are context-aware are implemented, this field reads as 0b1111.
This field either has the same value as ID_AA64DFR0_EL1.SEBEP or reads as zero.
Number of watchpoints, minus 1.
If FEAT_Debugv8p9 is implemented and 16 or more watchpoints are implemented, this field reads as 0b1111.
The value of 0b0000 is reserved.
This field either has the same value as ID_AA64DFR0_EL1.PMSS or reads as zero.
Number of breakpoints, minus 1.
If FEAT_Debugv8p9 is implemented and 16 or more breakpoints are implemented, this field reads as 0b1111.
The value of 0b0000 is reserved.
Performance Monitors Extension version.
This field does not follow the standard ID scheme, but uses the alternative ID scheme described in 'Alternative ID scheme used for the Performance Monitors Extension version'
Defined values are:
PMUVer | Meaning |
---|---|
0b0000 |
Performance Monitors Extension not implemented. |
0b0001 |
Performance Monitors Extension, PMUv3 implemented. |
0b0100 | PMUv3 for Armv8.1. As 0b0001, and adds support for:
|
0b0101 |
PMUv3 for Armv8.4. As 0b0100, and adds support for the PMMIR_EL1 register. |
0b0110 | PMUv3 for Armv8.5. As 0b0101, and adds support for: |
0b0111 | PMUv3 for Armv8.7. As 0b0110, and adds support for: |
0b1000 | PMUv3 for Armv8.8. As 0b0111, and:
|
0b1001 | PMUv3 for Armv8.9. As 0b1000, and:
|
0b1111 |
IMPLEMENTATION DEFINED form of performance monitors supported, PMUv3 not supported. Arm does not recommend this value for new implementations. |
All other values are reserved.
FEAT_PMUv3 implements the functionality identified by the value 0b0001.
FEAT_PMUv3p1 implements the functionality identified by the value 0b0100.
FEAT_PMUv3p4 implements the functionality identified by the value 0b0101.
FEAT_PMUv3p5 implements the functionality identified by the value 0b0110.
FEAT_PMUv3p7 implements the functionality identified by the value 0b0111.
FEAT_PMUv3p8 implements the functionality identified by the value 0b1000.
FEAT_PMUv3p9 implements the functionality identified by the value 0b1001.
From Armv8.1, if FEAT_PMUv3 is implemented, the value 0b0001 is not permitted.
From Armv8.4, if FEAT_PMUv3 is implemented, the value 0b0100 is not permitted.
From Armv8.5, if FEAT_PMUv3 is implemented, the value 0b0101 is not permitted.
From Armv8.7, if FEAT_PMUv3 is implemented, the value 0b0110 is not permitted.
From Armv8.8, if FEAT_PMUv3 is implemented, the value 0b0111 is not permitted.
From Armv8.9, if FEAT_PMUv3 is implemented, the value 0b1000 is not permitted.
Trace support. Indicates whether System register interface to a trace unit is implemented. Defined values are:
TraceVer | Meaning |
---|---|
0b0000 |
Trace unit System registers not implemented. |
0b0001 |
Trace unit System registers implemented. |
All other values are reserved.
A value of 0b0000 only indicates that no System register interface to a trace unit is implemented. A trace unit might nevertheless be implemented without a System register interface.
In an Armv8-A implementation that supports AArch64, this field returns the value of ID_AA64DFR0_EL1.TraceVer.
Reserved, UNKNOWN.
Component | Offset | Instance | Range |
---|---|---|---|
Debug | 0xD28 | EDDFR | 31:0 |
This interface is accessible as follows:
Component | Offset | Instance | Range |
---|---|---|---|
Debug | 0xD2C | EDDFR | 63:32 |
This interface is accessible as follows:
30/09/2022 15:58; 21c5a6dd0fdaf10a712e2f2d6fffbdbd66d4d96f
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