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CNTPCT: Counter-timer Physical Count register

Purpose

Holds the 64-bit physical count value.

Configuration

AArch32 System register CNTPCT bits [63:0] are architecturally mapped to AArch64 System register CNTPCT_EL0[63:0].

This register is present only when AArch32 is supported. Otherwise, direct accesses to CNTPCT are UNDEFINED.

All reads to the CNTPCT occur in program order relative to reads to CNTPCTSS or CNTPCT.

Attributes

CNTPCT is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
Physical count value
Physical count value

Bits [63:0]

Physical count value.

The reset behavior of this field is:

Accessing CNTPCT

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

MRRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <Rt2>, <CRm>

coprocCRmopc1
0b11110b11100b0000

if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && !ELIsInHost(EL0) && CNTKCTL_EL1.EL0PCTEN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); else AArch64.AArch32SystemAccessTrap(EL1, 0x04); elsif ELUsingAArch32(EL1) && CNTKCTL.PL0PCTEN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && !ELIsInHost(EL2) && CNTHCTL_EL2.EL1PCTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif ELIsInHost(EL2) && HCR_EL2.TGE == '0' && CNTHCTL_EL2.EL1PCTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif ELIsInHost(EL0) && CNTHCTL_EL2.EL0PCTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && CNTHCTL.PL1PCTEN == '0' then AArch32.TakeHypTrapException(0x04); else if IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && !ELUsingAArch32(EL2) && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' && !ELIsInHost(EL0) then (R[t2], R[t]) = Split(PhysicalCountInt() - CNTPOFF_EL2, 32); else (R[t2], R[t]) = Split(PhysicalCountInt(), 32); elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && CNTHCTL_EL2.EL1PCTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && CNTHCTL.PL1PCTEN == '0' then AArch32.TakeHypTrapException(0x04); else if IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && !ELUsingAArch32(EL2) && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' then (R[t2], R[t]) = Split(PhysicalCountInt() - CNTPOFF_EL2, 32); else (R[t2], R[t]) = Split(PhysicalCountInt(), 32); elsif PSTATE.EL == EL2 then (R[t2], R[t]) = Split(PhysicalCountInt(), 32); elsif PSTATE.EL == EL3 then (R[t2], R[t]) = Split(PhysicalCountInt(), 32);