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TRFCR

Trace Filter Control Register

Provides EL1 controls for Trace.

Configuration

AArch32 System register TRFCR bits [31:0] are architecturally mapped to AArch64 System register TRFCR_EL1[31:0].

This register is present only when FEAT_AA32EL1 is implemented and FEAT_TRF is implemented. Otherwise, direct accesses to TRFCR are UNDEFINED.

Attributes

TRFCR is a 32-bit register.

Field descriptions

313029282726252423222120191817161514131211109876543210
RES0TSRES0E1TREE0TRE

Bits [31:7]:

Reserved, RES0.

TS, bits [6:5]:

Timestamp Control. Controls which timebase is used for trace timestamps.

TSMeaningApplies when
0b01

Virtual timestamp. The traced timestamp is the physical counter value minus the value of CNTVOFF.

0b10

Guest physical timestamp. The traced timestamp is the physical counter value minus a physical offset. If any of the following are true, the physical offset is zero, otherwise the physical offset is the value of CNTPOFF_EL2:

  • EL3 is implemented and is using AArch32.
  • EL3 is implemented, using AArch64, and SCR_EL3.ECVEn == 0b0.
  • EL2 is using AArch32.
  • EL2 is using AArch64 and CNTHCTL_EL2.ECV == 0b0.
  • FEAT_ECV_POFF is not implemented.
When FEAT_ECV is implemented
0b11

Physical timestamp. The traced timestamp is the physical counter value.

All other values are reserved.

This field is ignored by the PE when any of the following are true:

The reset behavior of this field is:

Bits [4:2]:

Reserved, RES0.

E1TRE, bit [1]:

EL1 Trace Enable.

E1TREMeaning
0b0

Tracing is prohibited in PL1 modes.

0b1

Tracing is allowed in PL1 modes.

This field is ignored if SelfHostedTraceEnabled() == FALSE.

The reset behavior of this field is:

E0TRE, bit [0]:

EL0 Trace Enable.

E0TREMeaning
0b0

Tracing is prohibited at EL0.

0b1

Tracing is allowed at EL0.

This field is ignored if any of the following are true:

The reset behavior of this field is:

Access Instructions

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

MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}

(coproc = 0b1111, opc1 = 0b000, CRn = 0b0001, CRm = 0b0010, opc2 = 0b001)

if !(IsFeatureImplemented(FEAT_AA32EL1) && IsFeatureImplemented(FEAT_TRF)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TTRF == '1' then UNDEFINED; elsif HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SDCR.TTRF == '1' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2.T1 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR.T1 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && MDCR_EL2.TTRF == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR.TTRF == '1' then AArch32.TakeHypTrapException(0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TTRF == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SDCR.TTRF == '1' then if EL3SDDUndef() then UNDEFINED; else AArch32.TakeMonitorTrapException(); else R[t] = TRFCR; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TTRF == '1' then UNDEFINED; elsif HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR.TTRF == '1' then UNDEFINED; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TTRF == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR.TTRF == '1' then if EL3SDDUndef() then UNDEFINED; else AArch32.TakeMonitorTrapException(); else R[t] = TRFCR; elsif PSTATE.EL == EL3 then if PSTATE.M != M32_Monitor && SDCR.TTRF == '1' then AArch32.TakeMonitorTrapException(); else R[t] = TRFCR;

MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}

(coproc = 0b1111, opc1 = 0b000, CRn = 0b0001, CRm = 0b0010, opc2 = 0b001)

if !(IsFeatureImplemented(FEAT_AA32EL1) && IsFeatureImplemented(FEAT_TRF)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TTRF == '1' then UNDEFINED; elsif HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SDCR.TTRF == '1' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2.T1 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR.T1 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && MDCR_EL2.TTRF == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HDCR.TTRF == '1' then AArch32.TakeHypTrapException(0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TTRF == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SDCR.TTRF == '1' then if EL3SDDUndef() then UNDEFINED; else AArch32.TakeMonitorTrapException(); else TRFCR = R[t]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TTRF == '1' then UNDEFINED; elsif HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR.TTRF == '1' then UNDEFINED; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TTRF == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SDCR.TTRF == '1' then if EL3SDDUndef() then UNDEFINED; else AArch32.TakeMonitorTrapException(); else TRFCR = R[t]; elsif PSTATE.EL == EL3 then if PSTATE.M != M32_Monitor && SDCR.TTRF == '1' then AArch32.TakeMonitorTrapException(); else TRFCR = R[t];

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