HVBAR, Hyp Vector Base Address Register
The HVBAR characteristics are:
Purpose
Holds the vector base address for any exception that is taken to Hyp mode.
Configuration
AArch32 System register HVBAR bits [31:0] are architecturally mapped to AArch64 System register VBAR_EL2[31:0] .
This register is present only when AArch32 is supported at any Exception level. Otherwise, direct accesses to HVBAR are UNDEFINED.
If EL2 is not implemented, this register is RES0 from EL3.
Attributes
HVBAR is a 32-bit register.
Field descriptions
The HVBAR bit assignments are:
| 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 |
| Vector Base Address | RES0 | ||||||||||||||||||||||||||||||
Bits [31:5]
Vector Base Address. Bits[31:5] of the base address of the exception vectors for exceptions taken to this Exception level. Bits[4:0] of an exception vector are the exception offset.
This field resets to an architecturally UNKNOWN value.
Bits [4:0]
Reserved, RES0.
Accessing the HVBAR
Accesses to this register use the following encodings:
MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
| coproc | opc1 | CRn | CRm | opc2 |
|---|---|---|---|---|
| 0b1111 | 0b100 | 0b1100 | 0b0000 | 0b000 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T12 == '1' then
AArch64.AArch32SystemAccessTrap(EL2, 0x03);
elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T12 == '1' then
AArch32.TakeHypTrapException(0x03);
else
UNDEFINED;
elsif PSTATE.EL == EL2 then
return HVBAR;
elsif PSTATE.EL == EL3 then
if SCR.NS == '0' then
UNDEFINED;
else
return HVBAR;
MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
| coproc | opc1 | CRn | CRm | opc2 |
|---|---|---|---|---|
| 0b1111 | 0b100 | 0b1100 | 0b0000 | 0b000 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T12 == '1' then
AArch64.AArch32SystemAccessTrap(EL2, 0x03);
elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T12 == '1' then
AArch32.TakeHypTrapException(0x03);
else
UNDEFINED;
elsif PSTATE.EL == EL2 then
HVBAR = R[t];
elsif PSTATE.EL == EL3 then
if SCR.NS == '0' then
UNDEFINED;
else
HVBAR = R[t];