The CNTP_TVAL characteristics are:
Holds the timer value for the EL1 physical timer.
AArch32 System register CNTP_TVAL bits [31:0] are architecturally mapped to AArch64 System register CNTP_TVAL_EL0[31:0].
This register is present only when AArch32 is supported. Otherwise, direct accesses to CNTP_TVAL are UNDEFINED.
CNTP_TVAL is a 32-bit register.
| 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 |
| TimerValue | |||||||||||||||||||||||||||||||
The TimerValue view of the EL1 physical timer.
On a read of this register:
On a write of this register, CNTP_CVAL is set to (CNTPCT + TimerValue), where TimerValue is treated as a signed 32-bit integer.
When CNTP_CTL.ENABLE is 1, the timer condition is met when (CNTPCT - CNTP_CVAL) is greater than or equal to zero. This means that TimerValue acts like a 32-bit downcounter timer. When the timer condition is met:
When CNTP_CTL.ENABLE is 0, the timer condition is not met, but CNTPCT continues to count, so the TimerValue view appears to continue to count down.
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
| coproc | opc1 | CRn | CRm | opc2 |
|---|---|---|---|---|
| 0b1111 | 0b000 | 0b1110 | 0b0010 | 0b000 |
if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && !(EL2Enabled() && HCR_EL2.<E2H,TGE> == '11') && CNTKCTL_EL1.EL0PTEN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); else AArch64.AArch32SystemAccessTrap(EL1, 0x03); elsif ELUsingAArch32(EL1) && CNTKCTL.PL0PTEN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '0' && CNTHCTL_EL2.EL1PCEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '10' && CNTHCTL_EL2.EL1PTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && CNTHCTL_EL2.EL0PTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && CNTHCTL.PL1PCEN == '0' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && SCR_EL3.NS == '0' && IsFeatureImplemented(FEAT_SEL2) then if CNTHPS_CTL_EL2.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTHPS_CVAL_EL2 - PhysicalCountInt())<31:0>; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && SCR_EL3.NS == '1' then if CNTHP_CTL_EL2.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTHP_CVAL_EL2 - PhysicalCountInt())<31:0>; elsif IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && !ELUsingAArch32(EL2) && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' && HCR_EL2.<E2H,TGE> != '11' then if CNTP_CTL.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL - (PhysicalCountInt() - CNTPOFF_EL2))<31:0>; elsif HaveEL(EL3) && ELUsingAArch32(EL3) then if SCR.NS == '1' then if CNTP_CTL_NS.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL_NS - PhysicalCountInt())<31:0>; else if CNTP_CTL_S.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL_S - PhysicalCountInt())<31:0>; else if CNTP_CTL.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL - PhysicalCountInt())<31:0>; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '0' && CNTHCTL_EL2.EL1PCEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' && CNTHCTL_EL2.EL1PTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && CNTHCTL.PL1PCEN == '0' then AArch32.TakeHypTrapException(0x03); elsif IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && !ELUsingAArch32(EL2) && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' then if CNTP_CTL.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL - (PhysicalCountInt() - CNTPOFF_EL2))<31:0>; elsif HaveEL(EL3) && ELUsingAArch32(EL3) then if CNTP_CTL_NS.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL_NS - PhysicalCountInt())<31:0>; else if CNTP_CTL.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL - PhysicalCountInt())<31:0>; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && ELUsingAArch32(EL3) then if CNTP_CTL_NS.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL_NS - PhysicalCountInt())<31:0>; else if CNTP_CTL.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL - PhysicalCountInt())<31:0>; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then if CNTP_CTL_S.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL_S - PhysicalCountInt())<31:0>; else if CNTP_CTL_NS.ENABLE == '0' then R[t] = bits(32) UNKNOWN; else R[t] = (CNTP_CVAL_NS - PhysicalCountInt())<31:0>;
| coproc | opc1 | CRn | CRm | opc2 |
|---|---|---|---|---|
| 0b1111 | 0b000 | 0b1110 | 0b0010 | 0b000 |
if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && !(EL2Enabled() && HCR_EL2.<E2H,TGE> == '11') && CNTKCTL_EL1.EL0PTEN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); else AArch64.AArch32SystemAccessTrap(EL1, 0x03); elsif ELUsingAArch32(EL1) && CNTKCTL.PL0PTEN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.TGE == '1' then AArch32.TakeHypTrapException(0x00); else UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '0' && CNTHCTL_EL2.EL1PCEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '10' && CNTHCTL_EL2.EL1PTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && CNTHCTL_EL2.EL0PTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && CNTHCTL.PL1PCEN == '0' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && SCR_EL3.NS == '0' && IsFeatureImplemented(FEAT_SEL2) then CNTHPS_CVAL_EL2 = SignExtend(R[t], 64) + PhysicalCountInt(); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && SCR_EL3.NS == '1' then CNTHP_CVAL_EL2 = SignExtend(R[t], 64) + PhysicalCountInt(); elsif IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && !ELUsingAArch32(EL2) && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' && HCR_EL2.<E2H,TGE> != '11' then CNTP_CVAL = (SignExtend(R[t], 64) + PhysicalCountInt()) - CNTPOFF_EL2; elsif HaveEL(EL3) && ELUsingAArch32(EL3) then if SCR.NS == '1' then CNTP_CVAL_NS = SignExtend(R[t], 64) + PhysicalCountInt(); else CNTP_CVAL_S = SignExtend(R[t], 64) + PhysicalCountInt(); else CNTP_CVAL = SignExtend(R[t], 64) + PhysicalCountInt(); elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '0' && CNTHCTL_EL2.EL1PCEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' && CNTHCTL_EL2.EL1PTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && CNTHCTL.PL1PCEN == '0' then AArch32.TakeHypTrapException(0x03); elsif IsFeatureImplemented(FEAT_ECV) && EL2Enabled() && !ELUsingAArch32(EL2) && SCR_EL3.ECVEn == '1' && CNTHCTL_EL2.ECV == '1' then CNTP_CVAL = (SignExtend(R[t], 64) + PhysicalCountInt()) - CNTPOFF_EL2; elsif HaveEL(EL3) && ELUsingAArch32(EL3) then CNTP_CVAL_NS = SignExtend(R[t], 64) + PhysicalCountInt(); else CNTP_CVAL = SignExtend(R[t], 64) + PhysicalCountInt(); elsif PSTATE.EL == EL2 then if HaveEL(EL3) && ELUsingAArch32(EL3) then CNTP_CVAL_NS = SignExtend(R[t], 64) + PhysicalCountInt(); else CNTP_CVAL = SignExtend(R[t], 64) + PhysicalCountInt(); elsif PSTATE.EL == EL3 then if SCR.NS == '0' then CNTP_CVAL_S = SignExtend(R[t], 64) + PhysicalCountInt(); else CNTP_CVAL_NS = SignExtend(R[t], 64) + PhysicalCountInt();
04/07/2023 11:25; 1b994cb0b8c6d1ae5a9a15edbc8bd6ce3b5c7d68
Copyright © 2010-2023 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.