DISR

AArch32 System register DISR bits [31:0] are architecturally mapped to AArch64 System register DISR_EL1[31:0].

This register is present only when FEAT_RAS is implemented and EL1 is capable of using AArch32. Otherwise, direct accesses to DISR are UNDEFINED.

Attributes

Field descriptions

When the ESB instruction is executed at EL2:

A, bit [31]

Bits [30:12]

AET, bits [11:10]

EA, bit [9]

Bits [8:6]

DFSC, bits [5:0]

When the ESB instruction is executed at EL0 or EL1 and where TTBCR.EAE == 0:

A, bit [31]

Bits [30:16]

AET, bits [15:14]

Bit [13]

ExT, bit [12]

Bit [11]

FS, bits [10, 3:0]

LPAE, bit [9]

Bits [8:4]

When the ESB instruction is executed at EL0 or EL1 and where TTBCR.EAE == 1:

A, bit [31]

Bits [30:16]

AET, bits [15:14]

Bit [13]

ExT, bit [12]

Bits [11:10]

LPAE, bit [9]

Bits [8:6]

STATUS, bits [5:0]

LPAE	Meaning
0b0	Using the Short-descriptor translation table format.

LPAE	Meaning
0b1	Using the Long-descriptor translation table format.

Accessing DISR

An indirect write to DISR made by an ESB instruction does not require an explicit synchronization operation for the value that is written to be observed by a direct read of DISR occurring in program order after the ESB instruction.

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	0b000	0b1100	0b0001	0b001

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); elsif EL2Enabled() && !ELUsingAArch32(EL2) && (HCR_EL2.AMO == '1' || (IsFeatureImplemented(FEAT_DoubleFault2) && IsHCRXEL2Enabled() && HCRX_EL2.TMEA == '1')) then R[t] = VDISR_EL2<31:0>; elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.AMO == '1' then R[t] = VDISR; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && !Halted() && SCR_EL3.EA == '1' then R[t] = Zeros(32); elsif HaveEL(EL3) && ELUsingAArch32(EL3) && !Halted() && SCR.EA == '1' then R[t] = Zeros(32); else R[t] = DISR; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && !ELUsingAArch32(EL3) && !Halted() && SCR_EL3.EA == '1' then R[t] = Zeros(32); elsif HaveEL(EL3) && ELUsingAArch32(EL3) && !Halted() && SCR.EA == '1' then R[t] = Zeros(32); else R[t] = DISR; elsif PSTATE.EL == EL3 then R[t] = DISR;

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

coproc	opc1	CRn	CRm	opc2
0b1111	0b000	0b1100	0b0001	0b001

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); elsif EL2Enabled() && !ELUsingAArch32(EL2) && (HCR_EL2.AMO == '1' || (IsFeatureImplemented(FEAT_DoubleFault2) && IsHCRXEL2Enabled() && HCRX_EL2.TMEA == '1')) then VDISR_EL2 = R[t]; elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.AMO == '1' then VDISR = R[t]; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && !Halted() && SCR_EL3.EA == '1' then return; elsif HaveEL(EL3) && ELUsingAArch32(EL3) && !Halted() && SCR.EA == '1' then return; else DISR = R[t]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && !ELUsingAArch32(EL3) && !Halted() && SCR_EL3.EA == '1' then return; elsif HaveEL(EL3) && ELUsingAArch32(EL3) && !Halted() && SCR.EA == '1' then return; else DISR = R[t]; elsif PSTATE.EL == EL3 then DISR = 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
A	RES0																			AET		EA	RES0			DFSC

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
A	RES0															AET		RES0	ExT	RES0	FS[4]	LPAE	RES0					FS[3:0]

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
A	RES0															AET		RES0	ExT	RES0		LPAE	RES0			STATUS

DISR, Deferred Interrupt Status Register

Purpose

Configuration

Attributes

Field descriptions

When the ESB instruction is executed at EL2:

A, bit [31]

Bits [30:12]

AET, bits [11:10]

EA, bit [9]

Bits [8:6]

DFSC, bits [5:0]

When the ESB instruction is executed at EL0 or EL1 and where TTBCR.EAE == 0:

A, bit [31]

Bits [30:16]

AET, bits [15:14]

Bit [13]

ExT, bit [12]

Bit [11]

FS, bits [10, 3:0]

LPAE, bit [9]

Bits [8:4]

When the ESB instruction is executed at EL0 or EL1 and where TTBCR.EAE == 1:

A, bit [31]

Bits [30:16]

AET, bits [15:14]

Bit [13]

ExT, bit [12]

Bits [11:10]

LPAE, bit [9]

Bits [8:6]

STATUS, bits [5:0]

Accessing DISR

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

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