PMSIRR_EL1, Sampling Interval Reload Register

The PMSIRR_EL1 characteristics are:

Purpose

Defines the interval between samples

Configuration

This register is present only when SPE is implemented. Otherwise, direct accesses to PMSIRR_EL1 are UNDEFINED.

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

PMSIRR_EL1 is a 64-bit register.

Field descriptions

The PMSIRR_EL1 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
00000000000000000000000000000000
INTERVAL0000000RND
313029282726252423222120191817161514131211109876543210

Bits [63:32]

Reserved, RES0.

INTERVAL, bits [31:8]

Bits [31:8] of the PMSICR_EL1 interval counter reload value. Software must set this to a non-zero value. If software sets this to zero, an UNKNOWN sampling interval is used. Software should set this to a value greater than the minimum indicated by PMSIDR_EL1.Interval

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

Bits [7:1]

Reserved, RES0.

RND, bit [0]

Controls randomization of the sampling interval

RNDMeaning
0b0

Disable randomization of sampling interval

0b1

Add (pseudo-)random jitter to sampling interval

The random number generator is not architected.

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

Accessing the PMSIRR_EL1

Accesses to this register use the following encodings:

MRS <Xt>, PMSIRR_EL1

op0CRnop1op2CRm
0b110b10010b0000b0110b1001

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPMS == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_ELR.NS == '0' && MDCR_EL3.NSPB != '01' then AArch64.SystemAccessTrap(EL3, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_ELR.NS == '1' && MDCR_EL3.NSPB != '11' then AArch64.SystemAccessTrap(EL3, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<NV2,NV1,NV> == '1x1' then return NVMem[0x840]; else return PMSIRR_EL1; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_ELR.NS == '0' && MDCR_EL3.NSPB != '01' then AArch64.SystemAccessTrap(EL3, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_ELR.NS == '1' && MDCR_EL3.NSPB != '11' then AArch64.SystemAccessTrap(EL3, 0x18); else return PMSIRR_EL1; elsif PSTATE.EL == EL3 then return PMSIRR_EL1;

MSR PMSIRR_EL1, <Xt>

op0CRnop1op2CRm
0b110b10010b0000b0110b1001

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && MDCR_EL2.TPMS == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_ELR.NS == '0' && MDCR_EL3.NSPB != '01' then AArch64.SystemAccessTrap(EL3, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_ELR.NS == '1' && MDCR_EL3.NSPB != '11' then AArch64.SystemAccessTrap(EL3, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<NV2,NV1,NV> == '1x1' then NVMem[0x840] = X[t]; else PMSIRR_EL1 = X[t]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_ELR.NS == '0' && MDCR_EL3.NSPB != '01' then AArch64.SystemAccessTrap(EL3, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_ELR.NS == '1' && MDCR_EL3.NSPB != '11' then AArch64.SystemAccessTrap(EL3, 0x18); else PMSIRR_EL1 = X[t]; elsif PSTATE.EL == EL3 then PMSIRR_EL1 = X[t];




13/12/2018 16:42; 6379d01c197f1d40720d32d0f84c419c9187c009

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