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RVBAR
AArch32 Registers
AArch64 Registers
AArch32 Instructions
AArch64 Instructions
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External Registers
External Registers by Offset
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Proprietary Notice

RVBAR, Reset Vector Base Address Register

The RVBAR characteristics are:

Purpose

If EL3 is not implemented, contains the IMPLEMENTATION DEFINED address that execution starts from after reset when executing in AArch32 state.

Configuration

This register is present only when FEAT_AA32EL1 is implemented. Otherwise, direct accesses to RVBAR are UNDEFINED.

This register is implemented only if the highest Exception level implemented is capable of using AArch32, and is not EL3.

Attributes

RVBAR is a 32-bit register.

Field descriptions

313029282726252423222120191817161514131211109876543210
ResetAddressRES1

ResetAddress, bits [31:1]

Bits [31:1] of the IMPLEMENTATION DEFINED address that execution starts from after reset when executing in 32-bit state.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Bit [0]

Reserved, RES1.

Accessing RVBAR

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

MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}

coprocopc1CRnCRmopc2
0b11110b0000b11000b00000b001

if !IsFeatureImplemented(FEAT_AA32EL1) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if IsHighestEL(EL1) then R(t) = RVBAR(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HSTR_EL2().T12 == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HSTR().T12 == '1' then AArch32_TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && IsCurrentSecurityState(SS_Secure) then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && IsCurrentSecurityState(SS_Secure) then AArch64_AArch32SystemAccessTrap(EL3, 0x03); else Undefined(); end; elsif PSTATE.EL == EL2 then if IsHighestEL(EL2) then R(t) = RVBAR(); else Undefined(); end; elsif PSTATE.EL == EL3 then R(t) = MVBAR(); end;

AArch32 Registers
AArch64 Registers
AArch32 Instructions
AArch64 Instructions
Index by Encoding
External Registers
External Registers by Offset
Registers by Functional Group
Proprietary Notice

2026-03-12 12:23:09, 2025-09_rel_asl1

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