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TRCIDR3: Trace ID Register 3

Purpose

Returns the base architecture of the trace unit.

Configuration

AArch64 System register TRCIDR3 bits [31:0] are architecturally mapped to External register TRCIDR3[31:0].

This register is present only when FEAT_ETE is implemented and System register access to the trace unit registers is implemented. Otherwise, direct accesses to TRCIDR3 are UNDEFINED.

Attributes

TRCIDR3 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
NOOVERFLOWNUMPROC[2:0]SYSSTALLSTALLCTLSYNCPRTRCERRRES0EXLEVEL_NS_EL2EXLEVEL_NS_EL1EXLEVEL_NS_EL0EXLEVEL_S_EL3EXLEVEL_S_EL2EXLEVEL_S_EL1EXLEVEL_S_EL0RES0NUMPROC[4:3]CCITMIN

Bits [63:32]

Reserved, RES0.

NOOVERFLOW, bit [31]

Indicates if overflow prevention is implemented.

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

NOOVERFLOWMeaning
0b0

Overflow prevention is not implemented.

0b1

Overflow prevention is implemented.

If TRCIDR3.STALLCTL == 0 then this field is 0.

Access to this field is RO.

NUMPROC, bits [13:12, 30:28]

Indicates the number of PEs available for tracing.

NUMPROCMeaning
0b00000

The trace unit can trace one PE.

This field reads as 0b00000.

The NUMPROC field is split as follows:

Access to this field is RO.

SYSSTALL, bit [27]

Indicates if stalling of the PE is permitted.

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

SYSSTALLMeaning
0b0

Stalling of the PE is not permitted.

0b1

Stalling of the PE is permitted.

The value of this field might be dynamic and change based on system conditions.

If TRCIDR3.STALLCTL == 0 then this field is 0.

Access to this field is RO.

STALLCTL, bit [26]

Indicates if trace unit implements stalling of the PE.

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

STALLCTLMeaning
0b0

Stalling of the PE is not implemented.

0b1

Stalling of the PE is implemented.

Access to this field is RO.

SYNCPR, bit [25]

Indicates if an implementation has a fixed synchronization period.

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

SYNCPRMeaning
0b0

TRCSYNCPR is read/write so software can change the synchronization period.

0b1

TRCSYNCPR is read-only so the synchronization period is fixed.

This field reads as 0.

Access to this field is RO.

TRCERR, bit [24]

Indicates forced tracing of System Error exceptions is implemented.

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

TRCERRMeaning
0b0

Forced tracing of System Error exceptions is not implemented.

0b1

Forced tracing of System Error exceptions is implemented.

This field reads as 1.

Access to this field is RO.

Bit [23]

Reserved, RES0.

EXLEVEL_NS_EL2, bit [22]

Indicates if Non-secure EL2 is implemented.

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

EXLEVEL_NS_EL2Meaning
0b0

Non-secure EL2 is not implemented.

0b1

Non-secure EL2 is implemented.

Access to this field is RO.

EXLEVEL_NS_EL1, bit [21]

Indicates if Non-secure EL1 is implemented.

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

EXLEVEL_NS_EL1Meaning
0b0

Non-secure EL1 is not implemented.

0b1

Non-secure EL1 is implemented.

Access to this field is RO.

EXLEVEL_NS_EL0, bit [20]

Indicates if Non-secure EL0 is implemented.

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

EXLEVEL_NS_EL0Meaning
0b0

Non-secure EL0 is not implemented.

0b1

Non-secure EL0 is implemented.

Access to this field is RO.

EXLEVEL_S_EL3, bit [19]

Indicates if EL3 is implemented.

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

EXLEVEL_S_EL3Meaning
0b0

EL3 is not implemented.

0b1

EL3 is implemented.

Access to this field is RO.

EXLEVEL_S_EL2, bit [18]

Indicates if Secure EL2 is implemented.

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

EXLEVEL_S_EL2Meaning
0b0

Secure EL2 is not implemented.

0b1

Secure EL2 is implemented.

Access to this field is RO.

EXLEVEL_S_EL1, bit [17]

Indicates if Secure EL1 is implemented.

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

EXLEVEL_S_EL1Meaning
0b0

Secure EL1 is not implemented.

0b1

Secure EL1 is implemented.

Access to this field is RO.

EXLEVEL_S_EL0, bit [16]

Indicates if Secure EL0 is implemented.

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

EXLEVEL_S_EL0Meaning
0b0

Secure EL0 is not implemented.

0b1

Secure EL0 is implemented.

Access to this field is RO.

Bits [15:14]

Reserved, RES0.

CCITMIN, bits [11:0]

When TRCIDR0.TRCCCI == 0:

Indicates the minimum value that can be programmed in TRCCCCTLR.THRESHOLD.

Reads as 0x000.

Access to this field is RO.



When TRCIDR0.TRCCCI == 1:

Indicates the minimum value that can be programmed in TRCCCCTLR.THRESHOLD.

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

CCITMINMeaning
0x001..0xFFF

The minimum value that can be programmed in TRCCCCTLR.THRESHOLD.

The minimum value of this field is 0x001.

Access to this field is RO.



Otherwise:

Reserved, RES0.

Accessing TRCIDR3

Accesses to this register use the following encodings in the System register encoding space:

MRS <Xt>, TRCIDR3

op0op1CRnCRmop2
0b100b0010b00000b10110b111

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && CPTR_EL3.TTA == '1' then UNDEFINED; elsif CPACR_EL1.TTA == '1' then AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && CPTR_EL2.TTA == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.TRCID == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3.TTA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X[t, 64] = TRCIDR3; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && CPTR_EL3.TTA == '1' then UNDEFINED; elsif CPTR_EL2.TTA == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3.TTA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif !ELUsingAArch32(EL1) && IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X[t, 64] = TRCIDR3; elsif PSTATE.EL == EL3 then if CPTR_EL3.TTA == '1' then AArch64.SystemAccessTrap(EL3, 0x18); elsif !ELUsingAArch32(EL1) && IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X[t, 64] = TRCIDR3;