CNTPCT, Counter-timer Physical Count register

The CNTPCT characteristics are:

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 at any Exception level. 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

The CNTPCT bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
Physical count value
Physical count value
313029282726252423222120191817161514131211109876543210

Bits [63:0]

Physical count value.

Accessing the CNTPCT

Accesses to this register use the following encodings:

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

coprocCRmopc1
0b11110b11100b0000

if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && !(EL2Enabled() && HCR_EL2.<E2H,TGE> == '11') && 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) && HCR_EL2.E2H == '0' && CNTHCTL_EL2.EL1PCTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '10' && CNTHCTL_EL2.EL1PCTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && CNTHCTL_EL2.EL0PCTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && ELUsingAArch32(EL2) && CNTHCTL.PL1PCTEN == '0' then AArch32.TakeHypTrapException(0x04); else return CNTPCT; 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 return CNTPCT; elsif PSTATE.EL == EL2 then return CNTPCT; elsif PSTATE.EL == EL3 then return CNTPCT;




01/07/2020 15:57; 80324f0b9997bede489cc15ad1565345720bcd2a

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