HVBAR

AArch32 System register HVBAR bits [31:0] are architecturally mapped to AArch64 System register VBAR_EL2[31:0].

This register is present only when EL2 is capable of using AArch32. Otherwise, direct accesses to HVBAR are UNDEFINED.

Attributes

Field descriptions

VBA, 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.

The reset behavior of this field is:

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

Bits [4:0]

Accessing HVBAR

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

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 R[t] = HVBAR; elsif PSTATE.EL == EL3 then if SCR.NS == '0' then UNDEFINED; else R[t] = 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];

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																											RES0

HVBAR, Hyp Vector Base Address Register

Purpose