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TRCIDR4: Trace ID Register 4

Purpose

Returns the tracing capabilities of the trace unit.

Configuration

External register TRCIDR4 bits [31:0] are architecturally mapped to AArch64 System register TRCIDR4[31:0].

This register is present only when FEAT_ETE is implemented and FEAT_TRC_EXT is implemented. Otherwise, direct accesses to TRCIDR4 are RES0.

Attributes

TRCIDR4 is a 32-bit register.

Field descriptions

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NUMVMIDCNUMCIDCNUMSSCCNUMRSPAIRNUMPCRES0SUPPDACNUMDVCNUMACPAIRS

NUMVMIDC, bits [31:28]

Indicates the number of Virtual Context Identifier Comparators that are available for tracing.

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

NUMVMIDCMeaning
0b0000..0b1000

The number of Virtual Context Identifier Comparators in this implementation.

All other values are reserved.

Access to this field is RO.

NUMCIDC, bits [27:24]

Indicates the number of Context Identifier Comparators that are available for tracing.

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

NUMCIDCMeaning
0b0000..0b1000

The number of Context Identifier Comparators in this implementation.

All other values are reserved.

Access to this field is RO.

NUMSSCC, bits [23:20]

Indicates the number of Single-shot Comparator Controls that are available for tracing.

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

NUMSSCCMeaning
0b0000..0b1000

The number of Single-shot Comparator Controls in this implementation.

All other values are reserved.

Access to this field is RO.

NUMRSPAIR, bits [19:16]

Indicates the number of resource selector pairs that are available for tracing.

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

NUMRSPAIRMeaning
0b0000

This implementation has zero resource selector pairs.

0b0001..0b1111

The number of resource selector pairs in this implementation, minus one.

All other values are reserved.

Access to this field is RO.

NUMPC, bits [15:12]

Indicates the number of PE Comparator Inputs that are available for tracing.

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

NUMPCMeaning
0b0000..0b1000

The number of PE Comparator Inputs in this implementation.

All other values are reserved.

Access to this field is RO.

Bits [11:9]

Reserved, RES0.

SUPPDAC, bit [8]

When TRCIDR4.NUMACPAIRS != 0b0000:

Indicates whether data address comparisons are implemented. Data address comparisons are not implemented in ETE and are reserved for other trace architectures. Allocated in other trace architectures.

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

SUPPDACMeaning
0b0

Data address comparisons not implemented.

0b1

Data address comparisons implemented.

This field reads as 0b0.

Access to this field is RO.



Otherwise:

Reserved, RES0.

NUMDVC, bits [7:4]

Indicates the number of data value comparators. Data value comparators are not implemented in ETE and are reserved for other trace architectures. Allocated in other trace architectures.

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

NUMDVCMeaning
0b0000..0b1000

The number of data value comparators in this implementation.

All other values are reserved.

This field reads as 0b0000.

Access to this field is RO.

NUMACPAIRS, bits [3:0]

Indicates the number of Address Comparator pairs that are available for tracing.

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

NUMACPAIRSMeaning
0b0000..0b1000

The number of Address Comparator pairs in this implementation.

All other values are reserved.

Access to this field is RO.

Accessing TRCIDR4

TRCIDR4 can be accessed through the external debug interface:

ComponentOffsetInstance
ETE0x1F0TRCIDR4

This interface is accessible as follows: