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# ICV_EOIR0_EL1, Interrupt Controller Virtual End Of Interrupt Register 0

The ICV_EOIR0_EL1 characteristics are:

## Purpose

A PE writes to this register to inform the CPU interface that it has completed the processing of the specified virtual Group 0 interrupt.

## Configuration

AArch64 System register ICV_EOIR0_EL1 performs the same function as AArch32 System register ICV_EOIR0.

## Attributes

ICV_EOIR0_EL1 is a 64-bit register.

## Field descriptions

The ICV_EOIR0_EL1 bit assignments are:

63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32
RES0
RES0 | INTID
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

#### Bits [63:24]

Reserved, RES0.

#### INTID, bits [23:0]

The INTID from the corresponding ICV_IAR0_EL1 access.

This field has either 16 or 24 bits implemented. The number of implemented bits can be found in ICV_CTLR_EL1.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_EL1 to deactivate the virtual interrupt.

## Accessing the ICV_EOIR0_EL1

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_EL1, 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:

#### MSR ICC_EOIR0_EL1, <Xt>

op0 | op1 | CRn | CRm | op2
--- | --- | --- | --- | ---
0b11 | 0b000 | 0b1100 | 0b1000 | 0b001

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if ICC_SRE_EL1.SRE == '0' then AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && ICH_HCR_EL2.TALL0 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.FMO == '1' then ICV_EOIR0_EL1 = X[t]; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else ICC_EOIR0_EL1 = X[t]; elsif PSTATE.EL == EL2 then if ICC_SRE_EL2.SRE == '0' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else ICC_EOIR0_EL1 = X[t]; elsif PSTATE.EL == EL3 then if ICC_SRE_EL3.SRE == '0' then AArch64.SystemAccessTrap(EL3, 0x18); else ICC_EOIR0_EL1 = X[t];

AArch32 Registers | AArch64 Registers | AArch32 Instructions | AArch64 Instructions | Index by Encoding | External Registers | External Registers by Offset | Registers by Functional Group | Proprietary Notice

27/03/2019 21:59; e5e4db499bf9867a4b93324c4dbac985d3da9376

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