Trace Resources Status Register
Use this to set, or read, the status of the resources.
AArch64 System register TRCRSR bits [31:0] are architecturally mapped to External register TRCRSR[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 TRCRSR are UNDEFINED.
TRCRSR 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 | |||||||||||||||||||||||||||||||
| RES0 | TA | EVENT[3] | EVENT[2] | EVENT[1] | EVENT[0] | RES0 | EXTIN[3] | EXTIN[2] | EXTIN[1] | EXTIN[0] | |||||||||||||||||||||
Reserved, RES0.
Tracing active.
| TA | Meaning |
|---|---|
| 0b0 |
Tracing is not active. |
| 0b1 |
Tracing is active. |
The reset behavior of this field is:
Untraced status of ETEEvents.
| EVENT[<m>] | Meaning |
|---|---|
| 0b0 |
An ETEEvent <m> has not occurred. |
| 0b1 |
An ETEEvent <m> has occurred while the resources were in the Paused state. |
The reset behavior of this field is:
Accessing this field has the following behavior:
Reserved, RES0.
The sticky status of the External Input Selectors.
| EXTIN[<m>] | Meaning |
|---|---|
| 0b0 |
An event selected by External Input Selector <m> has not occurred. |
| 0b1 |
At least one event selected by External Input Selector <m> has occurred while the resources were in the Paused state. |
The reset behavior of this field is:
Accessing this field has the following behavior:
Must always be programmed.
If the trace unit is not in the Idle state it is CONSTRAINED UNPREDICTABLE whether writes to this register are ignored.
Reads from this register might return an UNKNOWN value if the trace unit is not in either of the Idle or Stable states.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, TRCRSR
(op0 = 0b10, op1 = 0b001, CRn = 0b0000, CRm = 0b1010, op2 = 0b000)
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().TRC == '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) = TRCRSR(); 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) = TRCRSR(); 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) = TRCRSR(); end; end;
MSR TRCRSR, <Xt>
(op0 = 0b10, op1 = 0b001, CRn = 0b0000, CRm = 0b1010, op2 = 0b000)
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') && HDFGWTR_EL2().TRC == '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 TRCRSR() = X{64}(t); 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 TRCRSR() = X{64}(t); 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 TRCRSR() = X{64}(t); end; end;
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