Interrupt Controller Virtual End Of Interrupt Register 0
A PE writes to this register to inform the CPU interface that it has completed the processing of the specified virtual Group 0 interrupt.
AArch32 System register ICV_EOIR0 bits [31:0] performs the same function as AArch64 System register ICV_EOIR0_EL1[31:0].
This register is present only when FEAT_AA32EL1 is implemented, GICv3 is implemented, and EL2 is implemented. Otherwise, direct accesses to ICV_EOIR0 are UNDEFINED.
ICV_EOIR0 is a 32-bit register.
| 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 |
| RES0 | INTID | ||||||||||||||||||||||||||||||
Reserved, RES0.
The INTID from the corresponding ICV_IAR0 access.
This field has either 16 or 24 bits implemented. The number of implemented bits can be found in ICV_CTLR.IDbits. If only 16 bits are implemented, bits [23:16] of this register are RES0.
If the ICV_CTLR.EOImode bit is 0, a write to this register drops the priority for the virtual interrupt, and also deactivates the virtual interrupt.
If the ICV_CTLR.EOImode bit is 1, a write to this register only drops the priority for the virtual interrupt. Software must write to ICV_DIR to deactivate the virtual interrupt.
A write to this register must correspond to the most recent valid read by this vPE from a Virtual Interrupt Acknowledge Register, and must correspond to the INTID that was read from ICV_IAR0, otherwise the system behavior is UNPREDICTABLE. A valid read is a read that returns a valid INTID that is not a special INTID.
Accesses to this register use the following encodings in the System register encoding space:
MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1111, opc1 = 0b000, CRn = 0b1100, CRm = 0b1000, opc2 = 0b001)
if !(IsFeatureImplemented(FEAT_AA32EL1) && IsFeatureImplemented(FEAT_GICv3)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then UNDEFINED; elsif HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR.FIQ == '1' then UNDEFINED; 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 ICC_SRE.SRE == '0' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && ICH_HCR_EL2.TALL0 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && ICH_HCR.TALL0 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2.FMO == '1' then ICV_EOIR0 = R[t]; elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR.FMO == '1' then ICV_EOIR0 = R[t]; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR.FIQ == '1' then if EL3SDDUndef() then UNDEFINED; else AArch32.TakeMonitorTrapException(); else ICC_EOIR0 = R[t]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then UNDEFINED; elsif HaveEL(EL3) && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR.FIQ == '1' then UNDEFINED; elsif ICC_HSRE.SRE == '0' then UNDEFINED; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR.FIQ == '1' then if EL3SDDUndef() then UNDEFINED; else AArch32.TakeMonitorTrapException(); else ICC_EOIR0 = R[t]; elsif PSTATE.EL == EL3 then if ICC_MSRE.SRE == '0' then UNDEFINED; else ICC_EOIR0 = R[t];
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