Vector Base Address Register (EL3)
Holds the vector base address for any exception that is taken to EL3.
This register is present only when EL3 is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to VBAR_EL3 are UNDEFINED.
VBAR_EL3 is a 64-bit register.
| 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 |
| VBA | |||||||||||||||||||||||||||||||
| VBA | RES0 | ||||||||||||||||||||||||||||||
Vector Base Address. Base address of the exception vectors for exceptions taken to EL3.
If the implementation supports FEAT_LVA3, then:
Otherwise:
If the implementation supports FEAT_LVA, then:
If the implementation does not support FEAT_LVA, then:
The reset behavior of this field is:
Reserved, RES0.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, VBAR_EL3
(op0 = 0b11, op1 = 0b110, CRn = 0b1100, CRm = 0b0000, op2 = 0b000)
if !(HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then X[t, 64] = VBAR_EL3;
MSR VBAR_EL3, <Xt>
(op0 = 0b11, op1 = 0b110, CRn = 0b1100, CRm = 0b0000, op2 = 0b000)
if !(HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then if IsFeatureImplemented(FEAT_FGWTE3) && FGWTE3_EL3.VBAR_EL3 == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else VBAR_EL3 = X[t, 64];
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