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# TRCIDR1, Trace ID Register 1

The TRCIDR1 characteristics are:

## Purpose

Returns the tracing capabilities of the trace unit.

## Configuration

AArch64 System register TRCIDR1 bits [31:0] are architecturally mapped to External register TRCIDR1[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 TRCIDR1 are UNDEFINED.

## Attributes

TRCIDR1 is a 64-bit register.

## Field descriptions

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
DESIGNER | RES0 | RES1 | TRCARCHMAJ | TRCARCHMIN | REVISION

#### Bits [63:32]

Reserved, RES0.

#### DESIGNER, bits [31:24]

Indicates which company designed the trace unit. The permitted values of this field are the same as MIDR_EL1.Implementer.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

#### Bits [23:16]

Reserved, RES0.

#### Bits [15:12]

Reserved, RES1.

#### TRCARCHMAJ, bits [11:8]

Major architecture version.

TRCARCHMAJ | Meaning
--- | ---
0b1111 | If both TRCIDR1.TRCARCHMAJ and TRCIDR1.TRCARCHMIN == 0xF then refer to TRCDEVARCH.

All other values are reserved.

This field reads as 0b1111.

Access to this field is RO.

#### TRCARCHMIN, bits [7:4]

Minor architecture version.

TRCARCHMIN | Meaning
--- | ---
0b1111 | If both TRCIDR1.TRCARCHMAJ and TRCIDR1.TRCARCHMIN == 0xF then refer to TRCDEVARCH.

All other values are reserved.

This field reads as 0b1111.

Access to this field is RO.

#### REVISION, bits [3:0]

Implementation revision.

Returns an IMPLEMENTATION DEFINED value that identifies the revision of the trace unit.

Arm deprecates any use of this field and recommends that implementations set this field to zero.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

## Accessing TRCIDR1

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

#### MRS <Xt>, TRCIDR1

op0 | op1 | CRn | CRm | op2
--- | --- | --- | --- | ---
0b10 | 0b001 | 0b0000 | 0b1001 | 0b111

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] = TRCIDR1; 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] = TRCIDR1; 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] = TRCIDR1;

AArch32 Registers | AArch64 Registers | AArch32 Instructions | AArch64 Instructions | Index by Encoding | External Registers | External Registers by Offset | Registers by Functional Group | Proprietary Notice

26/03/2024 09:49; 67c0ae5282a7629ba0ea0ba7267b43cd4f7939f6

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