VBAR_EL3

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VBAR_EL3, Vector Base Address Register (EL3)

Purpose

Configuration

This register is present only when EL3 is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to VBAR_EL3 are UNDEFINED.

Attributes

Field descriptions

VBA, bits [63:11]

Vector Base Address. Base address of the exception vectors for exceptions taken to EL3.

Note

If the implementation supports FEAT_LVA3, then:

If tagged addresses are not being used, bits [63:56] of VBAR_EL3 must be 0 or else the use of the vector address will result in a recursive exception.

Otherwise:

If the implementation supports FEAT_LVA, then:

If tagged addresses are being used, bits [55:52] of VBAR_EL3 must be 0 or else the use of the vector address will result in a recursive exception.
If tagged addresses are not being used, bits [63:52] of VBAR_EL3 must be 0 or else the use of the vector address will result in a recursive exception.

If the implementation does not support FEAT_LVA, then:

If tagged addresses are being used, bits [55:48] of VBAR_EL3 must be 0 or else the use of the vector address will result in a recursive exception.
If tagged addresses are not being used, bits [63:48] of VBAR_EL3 must be 0 or else the use of the vector address will result in a recursive exception.

The reset behavior of this field is:

On a Warm reset, this field resets to an architecturally UNKNOWN value.

Bits [10:0]

Accessing VBAR_EL3

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

MRS <Xt>, VBAR_EL3

op0	op1	CRn	CRm	op2
0b11	0b110	0b1100	0b0000	0b000

MSR VBAR_EL3, <Xt>

op0	op1	CRn	CRm	op2
0b11	0b110	0b1100	0b0000	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{64}(t); end; end;

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VBA
VBA																					RES0