CNTVCTSS

Holds the 64-bit virtual count value. The virtual count value is equal to the physical count value visible in CNTPCT minus the virtual offset visible in CNTVOFF.

Configuration

AArch32 System register CNTVCTSS bits [63:0] are architecturally mapped to AArch64 System register CNTVCTSS_EL0[63:0].

This register is present only when AArch32 is supported and FEAT_ECV is implemented. Otherwise, direct accesses to CNTVCTSS are UNDEFINED.

All reads to the CNTVCTSS occur in program order relative to reads to CNTVCT or CNTVCTSS.

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

Attributes

Field descriptions

Bits [63:0]

Accessing CNTVCTSS

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

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

coproc	CRm	opc1
0b1111	0b1110	0b1001

if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && !ELIsInHost(EL0) && CNTKCTL_EL1.EL0VCTEN == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); else AArch64.AArch32SystemAccessTrap(EL1, 0x04); elsif ELUsingAArch32(EL1) && CNTKCTL.PL0VCTEN == '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 ELIsInHost(EL0) && CNTHCTL_EL2.EL0VCTEN == '0' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); elsif EL2Enabled() && !ELUsingAArch32(EL2) && !ELIsInHost(EL0) && CNTHCTL_EL2.EL1TVCT == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); else if HaveEL(EL2) && !ELUsingAArch32(EL2) && (!EL2Enabled() || !ELIsInHost(EL0)) then (R[t2], R[t]) = Split(PhysicalCountInt() - CNTVOFF_EL2, 32); elsif HaveEL(EL2) && ELUsingAArch32(EL2) then (R[t2], R[t]) = Split(PhysicalCountInt() - CNTVOFF, 32); else (R[t2], R[t]) = Split(PhysicalCountInt(), 32); elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && CNTHCTL_EL2.EL1TVCT == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x04); else if HaveEL(EL2) && !ELUsingAArch32(EL2) then (R[t2], R[t]) = Split(PhysicalCountInt() - CNTVOFF_EL2, 32); elsif HaveEL(EL2) && ELUsingAArch32(EL2) then (R[t2], R[t]) = Split(PhysicalCountInt() - CNTVOFF, 32); else (R[t2], R[t]) = Split(PhysicalCountInt(), 32); elsif PSTATE.EL == EL2 then (R[t2], R[t]) = Split(PhysicalCountInt() - CNTVOFF, 32); elsif PSTATE.EL == EL3 then if HaveEL(EL2) then (R[t2], R[t]) = Split(PhysicalCountInt() - CNTVOFF, 32); else (R[t2], R[t]) = Split(PhysicalCountInt(), 32);

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
Self-Synchronized Virtual count value
Self-Synchronized Virtual count value