Interrupt Controller Virtual CPU interface Control Register
Controls behavior of the Virtual CPU interface.
This register is present only when FEAT_GCIE is implemented, (EL2 is implemented or EL3 is implemented), and FEAT_AA64 is implemented. Otherwise, direct accesses to ICH_VCTLR_EL2 are UNDEFINED.
If EL2 is not implemented, this register is RES0 from EL3.
ICH_VCTLR_EL2 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 | V3 | EN | |||||||||||||||||||||||||||||
Reserved, RES0.
Enable bit for Legacy operation.
If EL2 is not enabled in the Security state identified by SCR_EL3.{NSE,NS}, the Effective value of this field is 0.
When the Effective value of this field is 0, the Effective value of ICH_HCR_EL2.En is 0.
See 'Legacy virtual CPU interface' for more information.
| V3 | Meaning |
|---|---|
| 0b0 |
Legacy operation disabled. |
| 0b1 |
Legacy operation enabled. |
The reset behavior of this field is:
Reserved, RES0.
Enable interrupts for the Virtual Interrupt Domain.
If EL2 is not enabled in the Security state identified by SCR_EL3.{NSE,NS}, the Effective value of this field is 0.
| EN | Meaning |
|---|---|
| 0b0 |
Disabled. |
| 0b1 |
Enabled. |
When this field is 0, there is no HPPI of Sufficient priority for the Virtual Interrupt Domain.
The reset behavior of this field is:
Reserved, RES0.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, ICH_VCTLR_EL2
(op0 = 0b11, op1 = 0b100, CRn = 0b1100, CRm = 0b1011, op2 = 0b100)
if !(IsFeatureImplemented(FEAT_GCIE) && (HaveEL(EL2) || HaveEL(EL3)) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EffectiveHCR_EL2_NVx() IN {'1x1'} && (!IsFeatureImplemented(FEAT_GCIE_LEGACY) || (IsFeatureImplemented(FEAT_GCIE_LEGACY) && ICH_VCTLR_EL2().V3 == '0')) then X{64}(t) = NVMem(0xB28); elsif EffectiveHCR_EL2_NVx() IN {'xx1'} && (!IsFeatureImplemented(FEAT_GCIE_LEGACY) || (IsFeatureImplemented(FEAT_GCIE_LEGACY) && ICH_VCTLR_EL2().V3 == '0')) then AArch64_SystemAccessTrap(EL2, 0x18); else Undefined(); end; elsif PSTATE.EL == EL2 then X{64}(t) = ICH_VCTLR_EL2(); elsif PSTATE.EL == EL3 then X{64}(t) = ICH_VCTLR_EL2(); end;
MSR ICH_VCTLR_EL2, <Xt>
(op0 = 0b11, op1 = 0b100, CRn = 0b1100, CRm = 0b1011, op2 = 0b100)
if !(IsFeatureImplemented(FEAT_GCIE) && (HaveEL(EL2) || HaveEL(EL3)) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EffectiveHCR_EL2_NVx() IN {'1x1'} && (!IsFeatureImplemented(FEAT_GCIE_LEGACY) || (IsFeatureImplemented(FEAT_GCIE_LEGACY) && ICH_VCTLR_EL2().V3 == '0')) then NVMem(0xB28) = X{64}(t); elsif EffectiveHCR_EL2_NVx() IN {'xx1'} && (!IsFeatureImplemented(FEAT_GCIE_LEGACY) || (IsFeatureImplemented(FEAT_GCIE_LEGACY) && ICH_VCTLR_EL2().V3 == '0')) then AArch64_SystemAccessTrap(EL2, 0x18); else Undefined(); end; elsif PSTATE.EL == EL2 then ICH_VCTLR_EL2() = X{64}(t); elsif PSTATE.EL == EL3 then ICH_VCTLR_EL2() = X{64}(t); end;
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