VBAR_EL1, Vector Base Address Register (EL1)

The VBAR_EL1 characteristics are:

Purpose

Holds the vector base address for any exception that is taken to EL1.

Configuration

AArch64 System register VBAR_EL1 bits [31:0] are architecturally mapped to AArch32 System register VBAR[31:0] .

RW fields in this register reset to architecturally UNKNOWN values.

Attributes

VBAR_EL1 is a 129-bit register.

Field descriptions

The VBAR_EL1 bit assignments are:

When Morello is implemented and Capability access at EL1 is not trapped:

Bits [128:0]

Vector Base Address. Base address of the exception vectors for exceptions taken to EL1.

If the implementation does not support ARMv8.2-LVA, then:

If the implementation supports ARMv8.2-LVA, then:

Bits [10:0] are treated as 0 for the purpose of calculating the exception vector address.

This field resets to an architecturally UNKNOWN value.

When Morello is implemented and Capability access at EL1 is trapped:

Bits [128:64]

Reserved, RES0.

Bits [63:11]

Vector Base Address. Base address of the exception vectors for exceptions taken to EL1.

If the implementation does not support ARMv8.2-LVA, then:

If the implementation supports ARMv8.2-LVA, then:

This field resets to an architecturally UNKNOWN value.

Bits [10:0]

Reserved, RES0.

When Morello is not implemented:

6362616059585756555453525150494847464544434241403938373635343332
Vector Base Address
Vector Base AddressRES0
313029282726252423222120191817161514131211109876543210

Bits [63:11]

Vector Base Address. Base address of the exception vectors for exceptions taken to EL1.

If the implementation does not support ARMv8.2-LVA, then:

If the implementation supports ARMv8.2-LVA, then:

This field resets to an architecturally UNKNOWN value.

Bits [10:0]

Reserved, RES0.

Accessing the VBAR_EL1

When HCR_EL2.E2H is 1, without explicit synchronization, access from EL3 using a mnemonic ending in _EL1 or _EL12 are not guaranteed to be ordered with respect to accesses using a mnemonic with the other ending.

Accesses to this register use the following encodings:

MRS <Xt>, VBAR_EL1

op0op1CRnCRmop2
0b110b0000b11000b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL1 then AArch64.SystemAccessTrap(EL1, 0x18); elsif TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL3, 0x18); else return VBAR_EL1<63:0>; elsif PSTATE.EL == EL2 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL3, 0x18); elsif HCR_EL2.E2H == '1' then return VBAR_EL2<63:0>; else return VBAR_EL1<63:0>; elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x18); else return VBAR_EL1<63:0>;

MSR VBAR_EL1, <Xt>

op0op1CRnCRmop2
0b110b0000b11000b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL1 then AArch64.SystemAccessTrap(EL1, 0x18); elsif TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL3, 0x18); else VBAR_EL1 = ZeroExtend(X[t]); elsif PSTATE.EL == EL2 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL3, 0x18); elsif HCR_EL2.E2H == '1' then VBAR_EL2 = ZeroExtend(X[t]); else VBAR_EL1 = ZeroExtend(X[t]); elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x18); else VBAR_EL1 = ZeroExtend(X[t]);

MRS <Xt>, VBAR_EL12

op0op1CRnCRmop2
0b110b1010b11000b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL3, 0x18); else return VBAR_EL1<63:0>; else UNDEFINED; elsif PSTATE.EL == EL3 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x18); else return VBAR_EL1<63:0>; else UNDEFINED;

MSR VBAR_EL12, <Xt>

op0op1CRnCRmop2
0b110b1010b11000b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL3, 0x18); else VBAR_EL1 = ZeroExtend(X[t]); else UNDEFINED; elsif PSTATE.EL == EL3 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x18); else VBAR_EL1 = ZeroExtend(X[t]); else UNDEFINED;

MRS <Ct>, CVBAR_EL1

op0op1CRnCRmop2
0b110b0000b11000b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL1 then AArch64.SystemAccessTrap(EL1, 0x2A); elsif TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x2A); else AArch64.SystemAccessTrap(EL3, 0x2A); elsif CPACR_EL1.CEN == 'x0' then AArch64.SystemAccessTrap(EL1, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H != '1' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return VBAR_EL1; elsif PSTATE.EL == EL2 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x2A); else AArch64.SystemAccessTrap(EL3, 0x2A); elsif HCR_EL2.E2H == '0' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); elsif HCR_EL2.E2H == '1' then return VBAR_EL2; else return VBAR_EL1; elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x2A); elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return VBAR_EL1;

MSR CVBAR_EL1, <Ct>

op0op1CRnCRmop2
0b110b0000b11000b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL1 then AArch64.SystemAccessTrap(EL1, 0x2A); elsif TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x2A); else AArch64.SystemAccessTrap(EL3, 0x2A); elsif CPACR_EL1.CEN == 'x0' then AArch64.SystemAccessTrap(EL1, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H != '1' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else VBAR_EL1 = C[t]; elsif PSTATE.EL == EL2 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x2A); else AArch64.SystemAccessTrap(EL3, 0x2A); elsif HCR_EL2.E2H == '0' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); elsif HCR_EL2.E2H == '1' then VBAR_EL2 = C[t]; else VBAR_EL1 = C[t]; elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x2A); elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else VBAR_EL1 = C[t];

MRS <Ct>, CVBAR_EL12

op0op1CRnCRmop2
0b110b1010b11000b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x2A); else AArch64.SystemAccessTrap(EL3, 0x2A); elsif HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return VBAR_EL1; else UNDEFINED; elsif PSTATE.EL == EL3 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x2A); elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return VBAR_EL1; else UNDEFINED;

MSR CVBAR_EL12, <Ct>

op0op1CRnCRmop2
0b110b1010b11000b00000b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then if TargetELForCapabilityExceptions() == EL2 then AArch64.SystemAccessTrap(EL2, 0x2A); else AArch64.SystemAccessTrap(EL3, 0x2A); elsif HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else VBAR_EL1 = C[t]; else UNDEFINED; elsif PSTATE.EL == EL3 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x2A); elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else VBAR_EL1 = C[t]; else UNDEFINED;




12/01/2022 09:56; 05a4944b4b04e7ab50def8c126b479d22136f35b

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