Trace ID Register 1
Returns the tracing capabilities of the trace unit.
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.
TRCIDR1 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 |
| RES0 | |||||||||||||||||||||||||||||||
| DESIGNER | RES0 | RES1 | TRCARCHMAJ | TRCARCHMIN | REVISION | ||||||||||||||||||||||||||
Reserved, RES0.
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.
Reserved, RES0.
Reserved, RES1.
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.
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.
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.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, TRCIDR1
(op0 = 0b10, op1 = 0b001, CRn = 0b0000, CRm = 0b1001, op2 = 0b111)
if !(IsFeatureImplemented(FEAT_ETE) && IsFeatureImplemented(FEAT_TRC_SR)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && CPTR_EL3().TTA == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if 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); end; elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X{64}(t) = TRCIDR1(); end; elsif PSTATE.EL == EL2 then if 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); end; elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X{64}(t) = TRCIDR1(); end; elsif PSTATE.EL == EL3 then if CPTR_EL3().TTA == '1' then AArch64_SystemAccessTrap(EL3, 0x18); elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X{64}(t) = TRCIDR1(); end; end;
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