Interrupt Controller Interrupt Group 1 Enable Register (EL3)
Controls whether Group 1 interrupts are enabled or not.
This register is present only when GICv3 is implemented, EL3 is implemented, and FEAT_AA64 is implemented. Otherwise, direct accesses to ICC_IGRPEN1_EL3 are UNDEFINED.
ICC_IGRPEN1_EL3 is a 64-bit register.
| 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 |
| 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 | |||||||||||||||||||||||||||||||
| RES0 | EnableGrp1S | EnableGrp1NS | |||||||||||||||||||||||||||||
Reserved, RES0.
Enables Group 1 interrupts for the Secure state.
| EnableGrp1S | Meaning |
|---|---|
| 0b0 |
Secure Group 1 interrupts are disabled. |
| 0b1 |
Secure Group 1 interrupts are enabled. |
The Secure ICC_IGRPEN1_EL1.Enable bit is a read/write alias of the ICC_IGRPEN1_EL3.EnableGrp1S bit.
If the highest priority pending interrupt for that PE is a Group 1 interrupt using 1 of N model, then the interrupt will target another PE as a result of the Enable bit changing from 1 to 0.
The reset behavior of this field is:
Enables Group 1 interrupts for the Non-secure state.
| EnableGrp1NS | Meaning |
|---|---|
| 0b0 |
Non-secure Group 1 interrupts are disabled. |
| 0b1 |
Non-secure Group 1 interrupts are enabled. |
The Non-secure ICC_IGRPEN1_EL1.Enable bit is a read/write alias of the ICC_IGRPEN1_EL3.EnableGrp1NS bit.
If the highest priority pending interrupt for that PE is a Group 1 interrupt using 1 of N model, then the interrupt will target another PE as a result of the Enable bit changing from 1 to 0.
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, ICC_IGRPEN1_EL3
(op0 = 0b11, op1 = 0b110, CRn = 0b1100, CRm = 0b1100, op2 = 0b111)
if !(IsFeatureImplemented(FEAT_GICv3) && HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then if ICC_SRE_EL3.SRE == '0' then AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = ICC_IGRPEN1_EL3;
MSR ICC_IGRPEN1_EL3, <Xt>
(op0 = 0b11, op1 = 0b110, CRn = 0b1100, CRm = 0b1100, op2 = 0b111)
if !(IsFeatureImplemented(FEAT_GICv3) && HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then if ICC_SRE_EL3.SRE == '0' then AArch64.SystemAccessTrap(EL3, 0x18); else ICC_IGRPEN1_EL3 = X[t, 64];
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