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PMUACR_EL1

Performance Monitors User Access Control Register

Enables or disables EL0 access to specific Performance Monitors.

Configuration

This register is present only when FEAT_PMUv3p9 is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to PMUACR_EL1 are UNDEFINED.

Attributes

PMUACR_EL1 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0F0
CP30P29P28P27P26P25P24P23P22P21P20P19P18P17P16P15P14P13P12P11P10P9P8P7P6P5P4P3P2P1P0

Bits [63:33]:

Reserved, RES0.

F0, bit [32] when FEAT_PMUv3_ICNTR is implemented:

EL0 accesses to PMICNTR_EL0 enable. With PMUSERENR_EL0.UEN and PMUSERENR_EL0.IR, controls EL0 accesses to PMICNTR_EL0.

F0Meaning
0b0

If the Effective value of PMUSERENR_EL0.UEN is 1, then EL0 accesses to PMICNTR_EL0 and associated controls are RAZ/WI, and permitted EL0 writes to PMZR_EL0.F0 are ignored.

0b1

If the Effective value of PMUSERENR_EL0.UEN is 1, then EL0 accesses to PMICNTR_EL0 and associated controls are either read-only or read/write, depending on the value of PMUSERENR_EL0.IR.

The controls associated with PMICNTR_EL0 that are accessible at EL0 are PMCNTENSET_EL0.F0, PMCNTENCLR_EL0.F0, PMOVSSET_EL0.F0, and PMOVSCLR_EL0.F0.

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

The reset behavior of this field is:

Otherwise:

Reserved, RES0.

C, bit [31]:

EL0 accesses to PMCCNTR_EL0 enable. With PMUSERENR_EL0.EN, PMUSERENR_EL0.UEN, and PMUSERENR_EL0.CR, controls EL0 accesses to PMCCNTR_EL0.

CMeaning
0b0

If the Effective value of PMUSERENR_EL0.UEN is 1, then EL0 accesses to PMCCNTR_EL0 and associated controls are RAZ/WI, and permitted EL0 writes to PMZR_EL0.C are ignored.

0b1

If the Effective value of PMUSERENR_EL0.UEN is 1, then EL0 accesses to PMCCNTR_EL0 and associated controls are either read-only or read/write, depending on the value of PMUSERENR_EL0.CR.

The controls associated with PMCCNTR_EL0 that are accessible at EL0 are PMCNTENSET_EL0.C, PMCNTENCLR_EL0.C, PMOVSSET_EL0.C, and PMOVSCLR_EL0.C.

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

The reset behavior of this field is:

P<m>, bit [m], for m = 30 to 0:

EL0 accesses to PMEVCNTR<m>_EL0 enable. With PMUSERENR_EL0.EN, PMUSERENR_EL0.UEN, and PMUSERENR_EL0.ER, controls EL0 accesses to PMEVCNTR<m>_EL0.

P<m>Meaning
0b0

If the Effective value of PMUSERENR_EL0.UEN is 1, then EL0 accesses to PMEVCNTR<m>_EL0 and associated controls are RAZ/WI, and permitted EL0 writes to PMZR_EL0.P<m> are ignored.

0b1

If the Effective value of PMUSERENR_EL0.UEN is 1, then EL0 accesses to PMEVCNTR<m>_EL0 and associated controls are either read-only or read/write, depending on the value of PMUSERENR_EL0.ER.

The controls associated with PMEVCNTR<m>_EL0 that are accessible at EL0 are PMCNTENSET_EL0.P<m>, PMCNTENCLR_EL0.P<m>, PMOVSSET_EL0.P<m>, and PMOVSCLR_EL0.P<m>.

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

The reset behavior of this field is:

Accessing this field has the following behavior:

Access Instructions

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

MRS <Xt>, PMUACR_EL1

(op0 = 0b11, op1 = 0b000, CRn = 0b1001, CRm = 0b1110, op2 = 0b100)

if !(IsFeatureImplemented(FEAT_PMUv3p9) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && MDCR_EL3().EnPM2 == '0' then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && MDCR_EL3().TPM == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_FGT2) && ((HaveEL(EL3) && SCR_EL3().FGTEn2 == '0') || HDFGRTR2_EL2().nPMUACR_EL1 == '0') then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2().TPM == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3().EnPM2 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif HaveEL(EL3) && MDCR_EL3().TPM == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = PMUACR_EL1(); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && MDCR_EL3().EnPM2 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif HaveEL(EL3) && MDCR_EL3().TPM == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = PMUACR_EL1(); end; elsif PSTATE.EL == EL3 then X{64}(t) = PMUACR_EL1(); end;

MSR PMUACR_EL1, <Xt>

(op0 = 0b11, op1 = 0b000, CRn = 0b1001, CRm = 0b1110, op2 = 0b100)

if !(IsFeatureImplemented(FEAT_PMUv3p9) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && MDCR_EL3().EnPM2 == '0' then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && MDCR_EL3().TPM == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_FGT2) && ((HaveEL(EL3) && SCR_EL3().FGTEn2 == '0') || HDFGWTR2_EL2().nPMUACR_EL1 == '0') then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2().TPM == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3().EnPM2 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif HaveEL(EL3) && MDCR_EL3().TPM == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else PMUACR_EL1() = X{64}(t); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && MDCR_EL3().EnPM2 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif HaveEL(EL3) && MDCR_EL3().TPM == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else PMUACR_EL1() = X{64}(t); end; elsif PSTATE.EL == EL3 then PMUACR_EL1() = X{64}(t); end;


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