Holds the value of the processor Cycle Counter, CCNT, that counts processor clock cycles. See 'Time as measured by the Performance Monitors cycle counter' for more information.
PMCCFILTR determines the modes and states in which the PMCCNTR can increment.
AArch32 System register PMCCNTR bits [63:0] are architecturally mapped to AArch64 System register PMCCNTR_EL0[63:0].
AArch32 System register PMCCNTR bits [63:0] are architecturally mapped to External register PMU.PMCCNTR_EL0[63:0].
This register is present only when AArch32 is supported and FEAT_PMUv3 is implemented. Otherwise, direct accesses to PMCCNTR are UNDEFINED.
PMCCNTR is a 64-bit register that can also be accessed as a 32-bit value. If it is accessed as a 32-bit register, accesses read and write bits [31:0] and do not modify bits [63:32].
All counters are subject to any changes in clock frequency, including clock stopping caused by the WFI and WFE instructions. This means that it is CONSTRAINED UNPREDICTABLE whether or not PMCCNTR continues to increment when clocks are stopped by WFI and WFE instructions.
PMCCNTR 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 |
| CCNT | |||||||||||||||||||||||||||||||
| CCNT | |||||||||||||||||||||||||||||||
Cycle count. Depending on the values of PMCR.{LC,D}, this field increments in one of the following ways:
Writing 1 to PMCR.C sets this field to 0.
The reset behavior of this field is:
Permitted reads and writes of PMCCNTR are RAZ/WI if all of the following are true:
Permitted writes of PMCCNTR are ignored if all of the following are true:
Accesses to this register use the following encodings in the System register encoding space:
MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
| coproc | opc1 | CRn | CRm | opc2 |
|---|---|---|---|---|
| 0b1111 | 0b000 | 0b1001 | 0b1101 | 0b000 |
if PSTATE.EL == EL0 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif !ELUsingAArch32(EL1) && ((IsFeatureImplemented(FEAT_PMUv3p9) && PMUSERENR_EL0.<UEN,CR,EN> == '000') || (!IsFeatureImplemented(FEAT_PMUv3p9) && PMUSERENR_EL0.<CR,EN> == '00')) then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); else AArch64.AArch32SystemAccessTrap(EL1, 0x03); elsif ELUsingAArch32(EL1) && PMUSERENR.<CR,EN> == '00' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && !ELIsInHost(EL0) && HSTR_EL2.T9 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T9 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && !ELUsingAArch32(EL1) && !ELIsInHost(EL0) && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.PMCCNTR_EL0 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.TPM == '1' then AArch32.TakeHypTrapException(0x03); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); else R[t] = PMCCNTR<31:0>; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T9 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T9 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.TPM == '1' then AArch32.TakeHypTrapException(0x03); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); else R[t] = PMCCNTR<31:0>; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); else R[t] = PMCCNTR<31:0>; elsif PSTATE.EL == EL3 then R[t] = PMCCNTR<31:0>;
MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
| coproc | opc1 | CRn | CRm | opc2 |
|---|---|---|---|---|
| 0b1111 | 0b000 | 0b1001 | 0b1101 | 0b000 |
if PSTATE.EL == EL0 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif !ELUsingAArch32(EL1) && (PMUSERENR_EL0.EN == '0' && (!IsFeatureImplemented(FEAT_PMUv3p9) || PMUSERENR_EL0.UEN == '0')) then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); else AArch64.AArch32SystemAccessTrap(EL1, 0x03); elsif ELUsingAArch32(EL1) && PMUSERENR.EN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && !ELIsInHost(EL0) && HSTR_EL2.T9 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T9 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && !ELUsingAArch32(EL1) && !ELIsInHost(EL0) && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGWTR_EL2.PMCCNTR_EL0 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.TPM == '1' then AArch32.TakeHypTrapException(0x03); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); else PMCCNTR<31:0> = R[t]; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T9 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T9 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.TPM == '1' then AArch32.TakeHypTrapException(0x03); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); else PMCCNTR<31:0> = R[t]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); else PMCCNTR<31:0> = R[t]; elsif PSTATE.EL == EL3 then PMCCNTR<31:0> = R[t];
MRRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <Rt2>, <CRm>
| coproc | CRm | opc1 |
|---|---|---|
| 0b1111 | 0b1001 | 0b0000 |
if PSTATE.EL == EL0 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif !ELUsingAArch32(EL1) && ((IsFeatureImplemented(FEAT_PMUv3p9) && PMUSERENR_EL0.<UEN,CR,EN> == '000') || (!IsFeatureImplemented(FEAT_PMUv3p9) && PMUSERENR_EL0.<CR,EN> == '00')) then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); else AArch64.AArch32SystemAccessTrap(EL1, 0x04); elsif ELUsingAArch32(EL1) && PMUSERENR.<CR,EN> == '00' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && !ELIsInHost(EL0) && HSTR_EL2.T9 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T9 == '1' then AArch32.TakeHypTrapException(0x04); elsif EL2Enabled() && !ELUsingAArch32(EL1) && !ELIsInHost(EL0) && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.PMCCNTR_EL0 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.TPM == '1' then AArch32.TakeHypTrapException(0x04); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x04); else (R[t2], R[t]) = (PMCCNTR<63:32>, PMCCNTR<31:0>); elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T9 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T9 == '1' then AArch32.TakeHypTrapException(0x04); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.TPM == '1' then AArch32.TakeHypTrapException(0x04); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x04); else (R[t2], R[t]) = (PMCCNTR<63:32>, PMCCNTR<31:0>); elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x04); else (R[t2], R[t]) = (PMCCNTR<63:32>, PMCCNTR<31:0>); elsif PSTATE.EL == EL3 then (R[t2], R[t]) = (PMCCNTR<63:32>, PMCCNTR<31:0>);
MCRR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <Rt2>, <CRm>
| coproc | CRm | opc1 |
|---|---|---|
| 0b1111 | 0b1001 | 0b0000 |
if PSTATE.EL == EL0 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif !ELUsingAArch32(EL1) && (PMUSERENR_EL0.EN == '0' && (!IsFeatureImplemented(FEAT_PMUv3p9) || PMUSERENR_EL0.UEN == '0')) then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); else AArch64.AArch32SystemAccessTrap(EL1, 0x04); elsif ELUsingAArch32(EL1) && PMUSERENR.EN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && !ELIsInHost(EL0) && HSTR_EL2.T9 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T9 == '1' then AArch32.TakeHypTrapException(0x04); elsif EL2Enabled() && !ELUsingAArch32(EL1) && !ELIsInHost(EL0) && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGWTR_EL2.PMCCNTR_EL0 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.TPM == '1' then AArch32.TakeHypTrapException(0x04); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x04); else PMCCNTR = R[t2]:R[t]; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T9 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T9 == '1' then AArch32.TakeHypTrapException(0x04); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HDCR.TPM == '1' then AArch32.TakeHypTrapException(0x04); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x04); else PMCCNTR = R[t2]:R[t]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x04); else PMCCNTR = R[t2]:R[t]; elsif PSTATE.EL == EL3 then PMCCNTR = R[t2]:R[t];