Interrupt Controller Virtual Interrupt Priority Mask Register
Provides a virtual interrupt priority filter. Only virtual interrupts with a higher priority than the value in this register are signaled to the PE.
AArch64 System register ICV_PMR_EL1 bits [31:0] are architecturally mapped to AArch32 System register ICV_PMR[31:0].
This register is present only when (GICv3 is implemented or FEAT_GCIE_LEGACY is implemented), EL2 is implemented, and FEAT_AA64 is implemented. Otherwise, direct accesses to ICV_PMR_EL1 are UNDEFINED.
The effect of writes to ICV_PMR_EL1 are guaranteed to be visible to later instructions in the Execution stream. This ensures that no interrupts below the written PMR value will be taken after a write to this register is architecturally executed. For more information, see 'Observability of the effects of accesses to the GIC registers' in ARM® Generic Interrupt Controller Architecture Specification, GIC architecture version 3.0 and version 4.0 (ARM IHI 0069).
ICV_PMR_EL1 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 | Priority | ||||||||||||||||||||||||||||||
Reserved, RES0.
The priority mask level for the virtual CPU interface. If the priority of a virtual interrupt is higher than the value indicated by this field, the interface signals the virtual interrupt to the PE.
The possible priority field values are as follows:
| Implemented priority bits | Possible priority field values | Number of priority levels |
|---|---|---|
| [7:0] | 0x00-0xFF (0-255), all values | 256 |
| [7:1] | 0x00-0xFE (0-254), even values only | 128 |
| [7:2] | 0x00-0xFC (0-252), in steps of 4 | 64 |
| [7:3] | 0x00-0xF8 (0-248), in steps of 8 | 32 |
| [7:4] | 0x00-0xF0 (0-240), in steps of 16 | 16 |
Unimplemented priority bits are RAZ/WI.
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, ICC_PMR_EL1
(op0 = 0b11, op1 = 0b000, CRn = 0b0100, CRm = 0b0110, op2 = 0b000)
if !((IsFeatureImplemented(FEAT_GICv3) || IsFeatureImplemented(FEAT_GCIE_LEGACY)) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && SCR_EL3().[IRQ,FIQ] == '11' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if IsFeatureImplemented(FEAT_GCIE_LEGACY) && (ICH_VCTLR_EL2().V3 == '0' || !EL2Enabled() || !(ICH_HCR_EL2().TC == '1' || HCR_EL2().FMO == '1' || HCR_EL2().IMO == '1')) then Undefined(); elsif ICC_SRE_EL1().SRE == '0' then AArch64_SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && ICH_HCR_EL2().TC == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && HCR_EL2().FMO == '1' then X{64}(t) = ICV_PMR_EL1(); elsif EL2Enabled() && HCR_EL2().IMO == '1' then X{64}(t) = ICV_PMR_EL1(); elsif HaveEL(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = ICC_PMR_EL1(); end; elsif PSTATE.EL == EL2 then if IsFeatureImplemented(FEAT_GCIE_LEGACY) then Undefined(); elsif ICC_SRE_EL2().SRE == '0' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = ICC_PMR_EL1(); end; elsif PSTATE.EL == EL3 then if IsFeatureImplemented(FEAT_GCIE_LEGACY) then Undefined(); elsif ICC_SRE_EL3().SRE == '0' then AArch64_SystemAccessTrap(EL3, 0x18); else X{64}(t) = ICC_PMR_EL1(); end; end;
MSR ICC_PMR_EL1, <Xt>
(op0 = 0b11, op1 = 0b000, CRn = 0b0100, CRm = 0b0110, op2 = 0b000)
if !((IsFeatureImplemented(FEAT_GICv3) || IsFeatureImplemented(FEAT_GCIE_LEGACY)) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && SCR_EL3().[IRQ,FIQ] == '11' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if IsFeatureImplemented(FEAT_GCIE_LEGACY) && (ICH_VCTLR_EL2().V3 == '0' || !EL2Enabled() || !(ICH_HCR_EL2().TC == '1' || HCR_EL2().FMO == '1' || HCR_EL2().IMO == '1')) then Undefined(); elsif ICC_SRE_EL1().SRE == '0' then AArch64_SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && ICH_HCR_EL2().TC == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && HCR_EL2().FMO == '1' then ICV_PMR_EL1() = X{64}(t); elsif EL2Enabled() && HCR_EL2().IMO == '1' then ICV_PMR_EL1() = X{64}(t); elsif HaveEL(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else ICC_PMR_EL1() = X{64}(t); end; elsif PSTATE.EL == EL2 then if IsFeatureImplemented(FEAT_GCIE_LEGACY) then Undefined(); elsif ICC_SRE_EL2().SRE == '0' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else ICC_PMR_EL1() = X{64}(t); end; elsif PSTATE.EL == EL3 then if IsFeatureImplemented(FEAT_GCIE_LEGACY) then Undefined(); elsif ICC_SRE_EL3().SRE == '0' then AArch64_SystemAccessTrap(EL3, 0x18); else ICC_PMR_EL1() = X{64}(t); end; end;
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