PMCEID0_EL0, Performance Monitors Common Event Identification register 0

The PMCEID0_EL0 characteristics are:

Purpose

Defines which common architectural events and common microarchitectural events are implemented, or counted, using PMU events in the ranges 0x0000 to 0x001F and 0x4000 to 0x401F.

When the value of a bit in the register is 1 the corresponding common event is implemented and counted.

Note

Arm recommends that, if a common event is never counted, the value of the corresponding register bit is 0.

For more information about the common events and the use of the PMCEID<n>_EL0 registers see 'The PMU event number space and common events'.

Configuration

AArch64 System register PMCEID0_EL0 bits [31:0] are architecturally mapped to AArch32 System register PMCEID0[31:0] .

AArch64 System register PMCEID0_EL0 bits [63:32] are architecturally mapped to AArch32 System register PMCEID2[31:0] .

AArch64 System register PMCEID0_EL0 bits [31:0] are architecturally mapped to External register PMCEID0[31:0] .

AArch64 System register PMCEID0_EL0 bits [63:32] are architecturally mapped to External register PMCEID2[31:0] .

This register is present only when FEAT_PMUv3 is implemented. Otherwise, direct accesses to PMCEID0_EL0 are UNDEFINED.

Attributes

PMCEID0_EL0 is a 64-bit register.

Field descriptions

The PMCEID0_EL0 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
IDhi<n>, bit [n+32], for n = 0 to 31
ID31ID30ID29ID28ID27ID26ID25ID24ID23ID22ID21ID20ID19ID18ID17ID16ID15ID14ID13ID12ID11ID10ID9ID8ID7ID6ID5ID4ID3ID2ID1ID0
313029282726252423222120191817161514131211109876543210

IDhi<n>, bit [n+32], for n = 0 to 31

When FEAT_PMUv3p1 is implemented:

IDhi[n] corresponds to common event (0x4000 + n).

For each bit:

IDhi<n>Meaning
0b0

The common event is not implemented, or not counted.

0b1

The common event is implemented.

A bit that corresponds to a reserved event number is reserved. The value might be used in a future revision of the architecture to identify an additional common event.

Note

Such an event might be added retrospectively to an earlier version of the PMU architecture, provided the event does not require any additional PMU features and has an event number that can be represented in the PMCEID<n>_EL0 registers of that earlier version of the PMU architecture.


Otherwise:

Reserved, RES0.

ID<n>, bit [n], for n = 0 to 31

ID[n] corresponds to common event n.

For each bit:

ID<n>Meaning
0b0

The common event is not implemented, or not counted.

0b1

The common event is implemented.

A bit that corresponds to a reserved event number is reserved. The value might be used in a future revision of the architecture to identify an additional common event.

Note

Such an event might be added retrospectively to an earlier version of the PMU architecture, provided the event does not require any additional PMU features and has an event number that can be represented in the PMCEID<n>_EL0 registers of that earlier version of the PMU architecture.

Accessing the PMCEID0_EL0

Accesses to this register use the following encodings:

MRS <Xt>, PMCEID0_EL0

op0op1CRnCRmop2
0b110b0110b10010b11000b110

if PSTATE.EL == EL0 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TPM == '1' then UNDEFINED; elsif PMUSERENR_EL0.EN == '0' then if EL2Enabled() && HCR_EL2.TGE == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TPM == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return PMCEID0_EL0; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TPM == '1' then UNDEFINED; elsif EL2Enabled() && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TPM == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return PMCEID0_EL0; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && MDCR_EL3.TPM == '1' then UNDEFINED; elsif HaveEL(EL3) && MDCR_EL3.TPM == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return PMCEID0_EL0; elsif PSTATE.EL == EL3 then return PMCEID0_EL0;




01/07/2020 15:57; 80324f0b9997bede489cc15ad1565345720bcd2a

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