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CNTPCTSS_EL0: Counter-timer Self-Synchronized Physical Count Register

Purpose

Holds the self-synchronized view of the 64-bit physical count value.

Configuration

AArch64 System register CNTPCTSS_EL0 bits [63:0] are architecturally mapped to AArch32 System register CNTPCTSS[63:0].

This register is present only when FEAT_ECV is implemented. Otherwise, direct accesses to CNTPCTSS_EL0 are UNDEFINED.

All reads to the CNTPCTSS_EL0 occur in program order relative to reads to CNTPCT_EL0 or CNTPCTSS_EL0.

This register is a self-synchronised view of the CNTPCT_EL0 counter, and cannot be read speculatively.

Attributes

CNTPCTSS_EL0 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
Self-synchronized physical count value
Self-synchronized physical count value

Bits [63:0]

Self-synchronized physical count value.

The reset behavior of this field is:

Accessing CNTPCTSS_EL0

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

MRS <Xt>, CNTPCTSS_EL0

op0op1CRnCRmop2
0b110b0110b11100b00000b101

if PSTATE.EL == EL0 then if !ELIsInHost(EL0) && CNTKCTL_EL1.EL0PCTEN == '0' then if EL2Enabled() && HCR_EL2.TGE == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && !ELIsInHost(EL2) && CNTHCTL_EL2.EL1PCTEN == '0' then AArch64.SystemAccessTrap(EL2, 0x18); elsif ELIsInHost(EL2) && HCR_EL2.TGE == '0' && CNTHCTL_EL2.EL1PCTEN == '0' then AArch64.SystemAccessTrap(EL2, 0x18); elsif ELIsInHost(EL0) && CNTHCTL_EL2.EL0PCTEN == '0' then AArch64.SystemAccessTrap(EL2, 0x18); else if IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' && !ELIsInHost(EL0) then X[t, 64] = PhysicalCountInt() - CNTPOFF_EL2; else X[t, 64] = PhysicalCountInt(); elsif PSTATE.EL == EL1 then if EL2Enabled() && CNTHCTL_EL2.EL1PCTEN == '0' then AArch64.SystemAccessTrap(EL2, 0x18); else if IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' then X[t, 64] = PhysicalCountInt() - CNTPOFF_EL2; else X[t, 64] = PhysicalCountInt(); elsif PSTATE.EL == EL2 then X[t, 64] = PhysicalCountInt(); elsif PSTATE.EL == EL3 then X[t, 64] = PhysicalCountInt();