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PMUSERENR_EL0: Performance Monitors User Enable Register

Purpose

Enables or disables EL0 access to the Performance Monitors.

Configuration

AArch64 System register PMUSERENR_EL0 bits [31:0] are architecturally mapped to AArch32 System register PMUSERENR[31:0].

This register is present only when FEAT_PMUv3 is implemented. Otherwise, direct accesses to PMUSERENR_EL0 are UNDEFINED.

Attributes

PMUSERENR_EL0 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
RES0TIDIRUENERCRSWEN

Bits [63:7]

Reserved, RES0.

TID, bit [6]

When FEAT_PMUv3p9 is implemented:

Trap ID registers. Traps EL0 read access to common event identification registers.

TIDMeaning
0b0

Accesses to PMCEID<n>_EL0 and PMCEID<n> are not trapped by this mechanism.

0b1

EL0 read accesses to PMCEID<n>_EL0 and PMCEID<n> are trapped.

In AArch64 state, the register accesses affected by this control are:

In AArch32 state, the register accesses affected by this control are:

When trapped, reads generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

IR, bit [5]

When FEAT_PMUv3_ICNTR is implemented:

Instruction counter Read-only.

When PMUSERENR_EL0.UEN is 1, EL0 reads of the instruction counter and EL0 writes to PMZR_EL0 are enabled by PMUSERENR_EL0.UEN, unless trapped by another control, and PMUSERENR_EL0.IR controls the behavior of EL0 writes to the instruction counter and PMZR_EL0.

IRMeaning
0b0

Permitted EL0 writes are not affected by this mechanism.

0b1

Permitted EL0 writes to the instruction counter and PMZR_EL0.F0 are ignored.

In AArch64 state, when PMUSERENR_EL0.UEN is 1, MSR writes to PMZR_EL0 and PMICNTR_EL0 are affected by this control.

Ignored writes are not trapped and do not generate an exception.

This field is ignored by the PE when PMUSERENR_EL0.UEN == 0.

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

UEN, bit [4]

When FEAT_PMUv3p9 is implemented:

User Enable, with access controlled by PMUACR_EL1. Enables EL0 read/write access to PMU registers, other than PMCR_EL0.

UENMeaning
0b0

If FEAT_PMUv3_ICNTR is implemented, then EL0 accesses to PMICFILTR_EL0 and PMICNTR_EL0 are trapped.

EL0 accesses to the other specified PMU registers, PMCR_EL0, and PMCR are trapped, unless enabled by PMUSERENR_EL0.{ER,CR,SW,EN}.

0b1

EL0 accesses to the specified PMU registers are enabled, unless trapped by another control. The behavior of permitted accesses is controlled by PMUSERENR_EL0.{IR,ER,CR,SW} and PMUACR_EL1.

EL0 accesses to PMCR_EL0 and PMCR are trapped.

In AArch64 state, the register accesses affected by this control are:

In AArch32 state, the register accesses affected by this control are:

When trapped, reads and writes generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

This field is ignored by the PE and treated as zero when EL1 is using AArch32.

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

ER, bit [3]

When FEAT_PMUv3p9 is implemented:

Event counters Read enable or Read-only.

When PMUSERENR_EL0.{UEN,EN} is {0,0}, PMUSERENR_EL0.ER enables EL0 reads of the event counters and EL0 reads and writes of the select register.

When PMUSERENR_EL0.UEN is 1, EL0 reads of the event counters and EL0 writes to PMZR_EL0 are enabled by PMUSERENR_EL0.UEN, unless trapped by another control, and PMUSERENR_EL0.ER controls the behavior of EL0 writes to the event counters and PMZR_EL0.

ERMeaning
0b0

When PMUSERENR_EL0.UEN == 0, EL0 reads of the event counters and EL0 reads and writes of the select register are disabled, unless enabled by PMUSERENR_EL0.EN.

When PMUSERENR_EL0.UEN == 1, permitted EL0 writes are not affected by this mechanism.

0b1

When PMUSERENR_EL0.UEN == 0, EL0 reads of the event counters and EL0 reads and writes of the select register are enabled, unless trapped by another control.

When PMUSERENR_EL0.UEN == 1, permitted EL0 writes to the event counters and PMZR_EL0.P[30:0] are ignored.

In AArch64 state, the register accesses affected by this control are:

In AArch32 state, the register accesses affected by this control are:

When disabled, reads and writes generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

Ignored writes are not trapped and do not generate an exception.

This field is ignored by the PE when PMUSERENR_EL0.{UEN,EN} == {0,1}.

The reset behavior of this field is:



Otherwise:

Event counters Read enable.

When PMUSERENR_EL0.EN is 0, PMUSERENR_EL0.ER enables EL0 reads of the event counters and EL0 reads and writes of the select register.

ERMeaning
0b0

EL0 reads of the event counters and EL0 reads and writes of the select register are disabled, unless enabled by PMUSERENR_EL0.EN.

0b1

EL0 reads of the event counters and EL0 reads and writes of the select register are enabled, unless trapped by another control.

In AArch64 state, the register accesses affected by this control are:

In AArch32 state, the register accesses affected by this control are:

When disabled, reads and writes generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

This field is ignored by the PE when PMUSERENR_EL0.EN == 1.

The reset behavior of this field is:

CR, bit [2]

When FEAT_PMUv3p9 is implemented:

Cycle counter Read enable or Read-only.

When PMUSERENR_EL0.{UEN,EN} is {0,0}, PMUSERENR_EL0.CR enables EL0 reads of the cycle counter.

When PMUSERENR_EL0.UEN is 1, EL0 reads of the cycle counter and EL0 writes to PMZR_EL0 are enabled by PMUSERENR_EL0.UEN, unless trapped by another control, and PMUSERENR_EL0.CR controls the behavior of EL0 writes to the cycle counter and PMZR_EL0.

CRMeaning
0b0

When PMUSERENR_EL0.UEN == 0, EL0 reads of the cycle counter are disabled, unless enabled by PMUSERENR_EL0.EN.

When PMUSERENR_EL0.UEN == 1, permitted EL0 writes are not affected by this mechanism.

0b1

When PMUSERENR_EL0.UEN == 0, EL0 reads of the cycle counter are enabled, unless trapped by another control.

When PMUSERENR_EL0.UEN == 1, permitted EL0 writes to the cycle counter and PMZR_EL0.C are ignored.

In AArch64 state, the register accesses affected by this control are:

In AArch32 state, the register accesses affected by this control are:

When disabled, reads generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

Ignored writes are not trapped and do not generate an exception.

This field is ignored by the PE when PMUSERENR_EL0.{UEN,EN} == {0,1}.

The reset behavior of this field is:



Otherwise:

Cycle counter Read enable.

When PMUSERENR_EL0.EN is 0, PMUSERENR_EL0.CR enables EL0 reads of the cycle counter.

CRMeaning
0b0

EL0 reads of the cycle counter are disabled, unless enabled by PMUSERENR_EL0.EN.

0b1

EL0 reads of the cycle counter are enabled, unless trapped by another control.

In AArch64 state, the register accesses affected by this control are:

In AArch32 state, the register accesses affected by this control are:

When disabled, reads generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

This field is ignored by the PE when PMUSERENR_EL0.EN == 1.

The reset behavior of this field is:

SW, bit [1]

When FEAT_PMUv3p9 is implemented:

Software increment register Write enable.

When PMUSERENR_EL0.UEN is 0, PMUSERENR_EL0.SW enables EL0 writes to the Software increment register.

When PMUSERENR_EL0.UEN is 1, EL0 writes to the Software increment register are enabled by PMUSERENR_EL0.UEN, unless trapped by another control, and PMUSERENR_EL0.SW controls the behavior of EL0 writes to the Software increment register.

SWMeaning
0b0

When PMUSERENR_EL0.UEN == 0, EL0 writes to the Software increment register are disabled, unless enabled by PMUSERENR_EL0.EN.

When PMUSERENR_EL0.UEN == 1, permitted EL0 writes are not affected by this mechanism.

0b1

When PMUSERENR_EL0.UEN == 0, EL0 writes to the Software increment register are enabled, unless trapped by another control.

When PMUSERENR_EL0.UEN == 1, permitted EL0 writes to the Software increment register ignore the value of PMUACR_EL1.

In AArch64 state, the register accesses affected by this control are:

In AArch32 state, the register accesses affected by this control are:

When disabled, writes generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

This field is ignored by the PE when PMUSERENR_EL0.{UEN,EN} == {0,1}.

The reset behavior of this field is:



Otherwise:

Software increment register Write enable.

When PMUSERENR_EL0.EN is 0, PMUSERENR_EL0.SW enables EL0 writes to the Software increment register.

SWMeaning
0b0

EL0 writes to the Software increment register are disabled, unless enabled by PMUSERENR_EL0.EN.

0b1

EL0 writes to the Software increment register are enabled, unless trapped by another control.

In AArch64 state, the register accesses affected by this control are:

In AArch32 state, the register accesses affected by this control are:

When disabled, writes generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

This field is ignored by the PE when PMUSERENR_EL0.EN == 1.

The reset behavior of this field is:

EN, bit [0]

Enable.

Enables EL0 read/write access to PMU registers, other than the instruction counter.

ENMeaning
0b0

EL0 accesses to the specified PMU System registers are trapped, unless enabled by PMUSERENR_EL0.{UEN,ER,CR,SW}.

0b1

EL0 accesses to the specified PMU System registers are enabled, unless trapped by another control.

In AArch64 state, the register accesses affected by this control are:

Note

When FEAT_PMUv3_ICNTR is implemented, this field does not affect MRS and MSR accesses to PMICNTR_EL0 and PMICFILTR_EL0.

In AArch32 state, the register accesses affected by this control are:

When trapped, reads and writes generate an exception to EL1, or to EL2 when EL2 is implemented and enabled for the current Security state and HCR_EL2.TGE is 1, and:

This field is ignored by the PE when FEAT_PMUv3p9 is implemented and PMUSERENR_EL0.UEN == 1.

The reset behavior of this field is:

Accessing PMUSERENR_EL0

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

MRS <Xt>, PMUSERENR_EL0

op0op1CRnCRmop2
0b110b0110b10010b11100b000

if PSTATE.EL == EL0 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TPM == '1' then UNDEFINED; elsif EL2Enabled() && !ELIsInHost(EL0) && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.PMUSERENR_EL0 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = PMUSERENR_EL0; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TPM == '1' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.PMUSERENR_EL0 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = PMUSERENR_EL0; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TPM == '1' then UNDEFINED; elsif HaveEL(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = PMUSERENR_EL0; elsif PSTATE.EL == EL3 then X[t, 64] = PMUSERENR_EL0;

MSR PMUSERENR_EL0, <Xt>

op0op1CRnCRmop2
0b110b0110b10010b11100b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TPM == '1' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGWTR_EL2.PMUSERENR_EL0 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else PMUSERENR_EL0 = X[t, 64]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TPM == '1' then UNDEFINED; elsif HaveEL(EL3) && MDCR_EL3.TPM == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else PMUSERENR_EL0 = X[t, 64]; elsif PSTATE.EL == EL3 then PMUSERENR_EL0 = X[t, 64];