The CNTVOFF characteristics are:
Holds the 64-bit virtual offset. This is the offset between the physical count value visible in CNTPCT and the virtual count value visible in CNTVCT.
AArch32 System register CNTVOFF bits [63:0] are architecturally mapped to AArch64 System register CNTVOFF_EL2[63:0] .
If EL2 is not implemented, this register is RES0 from EL3 and the virtual counter uses a fixed virtual offset of zero.
When EL2 is implemented and is using AArch64, if HCR_EL2.{E2H, TGE} is {1, 1}, the virtual counter uses a fixed virtual offset of zero when CNTVCT is read from Non-secure EL0.
When EL2 is implemented and can use AArch32, on a reset into an Exception level that is using AArch32 this register resets to an IMPLEMENTATION DEFINED value that might be UNKNOWN.
CNTVOFF is a 64-bit register.
The CNTVOFF 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 |
Virtual offset | |||||||||||||||||||||||||||||||
Virtual offset | |||||||||||||||||||||||||||||||
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 |
Virtual offset.
This field resets to an architecturally UNKNOWN value.
Accesses to this register use the following encodings:
coproc | CRm | opc1 |
---|---|---|
0b1111 | 0b1110 | 0b0100 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then return CNTVOFF; elsif PSTATE.EL == EL3 then return CNTVOFF;
coproc | CRm | opc1 |
---|---|---|
0b1111 | 0b1110 | 0b0100 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then CNTVOFF = R[t2]:R[t]; elsif PSTATE.EL == EL3 then CNTVOFF = R[t2]:R[t];
27/03/2019 21:59; e5e4db499bf9867a4b93324c4dbac985d3da9376
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