PMOVSCLR_EL0, Performance Monitors Overflow Flag Status Clear Register

The PMOVSCLR_EL0 characteristics are:

Purpose

Contains the state of the overflow bit for the Cycle Count Register, PMCCNTR_EL0, and each of the implemented event counters PMEVCNTR<n>. Writing to this register clears these bits.

Configuration

AArch64 System register PMOVSCLR_EL0 bits [31:0] are architecturally mapped to AArch32 System register PMOVSR[31:0].

AArch64 System register PMOVSCLR_EL0 bits [31:0] are architecturally mapped to External register PMOVSCLR_EL0[31:0].

This register is present only when FEAT_PMUv3 is implemented. Otherwise, direct accesses to PMOVSCLR_EL0 are UNDEFINED.

Attributes

PMOVSCLR_EL0 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
CP30P29P28P27P26P25P24P23P22P21P20P19P18P17P16P15P14P13P12P11P10P9P8P7P6P5P4P3P2P1P0

Bits [63:32]

Reserved, RES0.

C, bit [31]

Cycle counter overflow clear bit.

CMeaning
0b0

When read, means the cycle counter has not overflowed since this bit was last cleared. When written, has no effect.

0b1

When read, means the cycle counter has overflowed since this bit was last cleared. When written, clears the cycle counter overflow bit to 0.

PMCR_EL0.LC controls whether an overflow is detected from unsigned overflow of PMCCNTR_EL0[31:0] or unsigned overflow of PMCCNTR_EL0[63:0].

The reset behaviour of this field is:

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

Event counter overflow clear bit for PMEVCNTR<n>_EL0.

If N is less than 31, then bits [30:N] are RAZ/WI. When EL2 is implemented and enabled in the current Security state, in EL1 and EL0, N is the value in MDCR_EL2.HPMN. Otherwise, N is the value in PMCR_EL0.N.

P<n>Meaning
0b0

When read, means that PMEVCNTR<n>_EL0 has not overflowed since this bit was last cleared. When written, has no effect.

0b1

When read, means that PMEVCNTR<n>_EL0 has overflowed since this bit was last cleared. When written, clears the PMEVCNTR<n>_EL0 overflow bit to 0.

If FEAT_PMUv3p5 is implemented, MDCR_EL2.HLP and PMCR_EL0.LP control whether an overflow is detected from unsigned overflow of PMEVCNTR<n>_EL0[31:0] or unsigned overflow of PMEVCNTR<n>_EL0[63:0].

The reset behaviour of this field is:

Accessing PMOVSCLR_EL0

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

MRS <Xt>, PMOVSCLR_EL0

op0op1CRnCRmop2
0b110b0110b10010b11000b011

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() && HCR_EL2.<E2H,TGE> != '11' && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.PMOVS == '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 Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return PMOVSCLR_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() && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.PMOVS == '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 Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else return PMOVSCLR_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 PMOVSCLR_EL0; elsif PSTATE.EL == EL3 then return PMOVSCLR_EL0;

MSR PMOVSCLR_EL0, <Xt>

op0op1CRnCRmop2
0b110b0110b10010b11000b011

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() && HCR_EL2.<E2H,TGE> != '11' && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGWTR_EL2.PMOVS == '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 Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else PMOVSCLR_EL0 = X[t]; 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() && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGWTR_EL2.PMOVS == '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 Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else PMOVSCLR_EL0 = X[t]; 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 PMOVSCLR_EL0 = X[t]; elsif PSTATE.EL == EL3 then PMOVSCLR_EL0 = X[t];


30/06/2021 15:21; 2a17f7750cfd1ab239f20f6cf29877ba8041794f

Copyright © 2010-2021 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.