The CNTPCT characteristics are:
Holds the 64-bit physical count value.
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.
CNTPCT is a 64-bit register.
The CNTPCT bit assignments are:
63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Physical count value | |||||||||||||||||||||||||||||||
Physical count value |
Physical count value.
On a Warm reset, this field resets to an architecturally UNKNOWN value.
Accesses to this register use the following encodings:
coproc | CRm | opc1 |
---|---|---|
0b1111 | 0b1110 | 0b0000 |
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 if IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && !ELUsingAArch32(EL2) && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' && HCR_EL2.<E2H,TGE> != '11' then return PhysicalCountInt() - CNTPOFF_EL2; else return PhysicalCountInt(); 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 return PhysicalCountInt() - CNTPOFF_EL2; else return PhysicalCountInt(); elsif PSTATE.EL == EL2 then return PhysicalCountInt(); elsif PSTATE.EL == EL3 then return PhysicalCountInt();
30/03/2021 20:51; e3551d56dc294a4d55296a6c10544191ada08a8e
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