Trace Event Control 1 Register
Controls the behavior of the ETEEvents that TRCEVENTCTL0R selects.
AArch64 System register TRCEVENTCTL1R bits [31:0] are architecturally mapped to External register TRCEVENTCTL1R[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 TRCEVENTCTL1R are UNDEFINED.
TRCEVENTCTL1R 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 | OE | LPOVERRIDE | ATB | RES0 | INSTEN[3] | INSTEN[2] | INSTEN[1] | INSTEN[0] | |||||||||||||||||||||||
Reserved, RES0.
ETE Trace Output Enable control.
| OE | Meaning |
|---|---|
| 0b0 |
Trace output to any IMPLEMENTATION DEFINED trace output interface is disabled. |
| 0b1 |
Trace output to any IMPLEMENTATION DEFINED trace output interface is enabled. |
The reset behavior of this field is:
Reserved, RES0.
Low-power Override Mode select.
| LPOVERRIDE | Meaning |
|---|---|
| 0b0 |
Trace unit Low-power Override Mode is not enabled. That is, the trace unit is permitted to enter low-power state. |
| 0b1 |
Trace unit Low-power Override Mode is enabled. That is, entry to a low-power state does not affect the trace unit resources or trace generation. |
Reserved, RES0.
AMBA Trace Bus (ATB) trigger enable.
If a CoreSight ATB interface is implemented then when ETEEvent 0 occurs the trace unit sets:
If the width of ATDATA is greater than the width of TRCTRACEIDR.TRACEID then the trace unit zeroes the upper ATDATA bits.
If ETEEvent 0 is programmed to occur based on program execution, such as an Address Comparator, the ATB trigger might not be inserted into the ATB stream at the same time as any trace generated by that program execution is output by the trace unit. Typically, the generated trace might be buffered in a trace unit which means that the ATB trigger would be output before the associated trace is output.
If ETEEvent 0 is asserted multiple times in close succession, the trace unit is required to generate an ATB trigger for the first assertion, but might ignore one or more of the subsequent assertions. Arm recommends that the window in which ETEEvent 0 is ignored is limited only by the time taken to output an ATB trigger.
| ATB | Meaning |
|---|---|
| 0b0 |
ATB trigger is disabled. |
| 0b1 |
ATB trigger is enabled. |
Reserved, RES0.
Reserved, RES0.
Event element control.
| INSTEN[<m>] | Meaning |
|---|---|
| 0b0 |
The trace unit does not generate an Event element <m>. |
| 0b1 |
The trace unit generates an Event element <m> when ETEEvent <m> occurs. |
Accessing this field has the following behavior:
Must be programmed.
If the trace unit is not in the Idle state it is CONSTRAINED UNPREDICTABLE whether writes to this register are ignored.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, TRCEVENTCTL1R
(op0 = 0b10, op1 = 0b001, CRn = 0b0000, CRm = 0b1001, 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) = TRCEVENTCTL1R(); 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) = TRCEVENTCTL1R(); 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) = TRCEVENTCTL1R(); end; end;
MSR TRCEVENTCTL1R, <Xt>
(op0 = 0b10, op1 = 0b001, CRn = 0b0000, CRm = 0b1001, 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 TRCEVENTCTL1R() = 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 TRCEVENTCTL1R() = 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 TRCEVENTCTL1R() = X{64}(t); end; end;
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