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 in the Warm reset domain. On a Warm or Cold reset RW fields in this register reset to architecturally UNKNOWN values.

Attributes

PMOVSCLR_EL0 is a 64-bit register.

Field descriptions

The PMOVSCLR_EL0 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
00000000000000000000000000000000
CP<n>, bit [n]
313029282726252423222120191817161514131211109876543210

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].

On a Warm reset, this field resets to an architecturally UNKNOWN value.

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

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 ARMv8.5-PMU 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].

On a Warm reset, this field resets to an architecturally UNKNOWN value.

Accessing the PMOVSCLR_EL0

Accesses to this register use the following encodings:

MRS <Xt>, PMOVSCLR_EL0

op0CRnop1op2CRm
0b110b10010b0110b0110b1100

if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && PMUSERENR_EL0.EN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else return PMOVSCLR_EL0; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else return PMOVSCLR_EL0; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else return PMOVSCLR_EL0; elsif PSTATE.EL == EL3 then return PMOVSCLR_EL0;

MSR PMOVSCLR_EL0, <Xt>

op0CRnop1op2CRm
0b110b10010b0110b0110b1100

if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && PMUSERENR_EL0.EN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else PMOVSCLR_EL0 = X[t]; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else PMOVSCLR_EL0 = X[t]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && !ELUsingAArch32(EL3) && MDCR_EL3.TPM == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else PMOVSCLR_EL0 = X[t]; elsif PSTATE.EL == EL3 then PMOVSCLR_EL0 = X[t];




13/12/2018 16:42; 6379d01c197f1d40720d32d0f84c419c9187c009

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