Interrupt Controller Interrupt Priority Mask Register
Provides an interrupt priority filter. Only interrupts with a higher priority than the value in this register are signaled to the PE.
AArch32 System register ICC_PMR bits [31:0] are architecturally mapped to AArch64 System register ICC_PMR_EL1[31:0].
This register is present only when FEAT_AA32EL1 is implemented and GICv3 is implemented. Otherwise, direct accesses to ICC_PMR are UNDEFINED.
The effect of writes to ICC_PMR 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).
ICC_PMR 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 | Priority | ||||||||||||||||||||||||||||||
Reserved, RES0.
The priority mask level for the CPU interface. If the priority of an interrupt is higher than the value indicated by this field, the interface signals the 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:
MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1111, opc1 = 0b000, CRn = 0b0100, CRm = 0b0110, opc2 = 0b000)
if !(IsFeatureImplemented(FEAT_AA32EL1) && IsFeatureImplemented(FEAT_GICv3)) then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR().[IRQ,FIQ] == '11' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if 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().TC == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && ICH_HCR().TC == '1' then AArch32_TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2().FMO == '1' then R(t) = ICV_PMR(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2().IMO == '1' then R(t) = ICV_PMR(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR().FMO == '1' then R(t) = ICV_PMR(); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR().IMO == '1' then R(t) = ICV_PMR(); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x03); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR().[IRQ,FIQ] == '11' then Undefined(); else R(t) = ICC_PMR(); end; elsif PSTATE.EL == EL2 then if ICC_HSRE().SRE == '0' then Undefined(); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x03); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR().[IRQ,FIQ] == '11' then Undefined(); else R(t) = ICC_PMR(); end; elsif PSTATE.EL == EL3 then if ICC_MSRE().SRE == '0' then Undefined(); elsif SCR().[IRQ,FIQ] == '11' && PSTATE.M != M32_Monitor then Undefined(); else R(t) = ICC_PMR(); end; end;
MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
(coproc = 0b1111, opc1 = 0b000, CRn = 0b0100, CRm = 0b0110, opc2 = 0b000)
if !(IsFeatureImplemented(FEAT_AA32EL1) && IsFeatureImplemented(FEAT_GICv3)) then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then Undefined(); elsif HaveEL(EL3) && PSTATE.EL IN {EL1, EL2} && EL3SDDUndefPriority() && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR().[IRQ,FIQ] == '11' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if 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().TC == '1' then AArch64_AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && ICH_HCR().TC == '1' then AArch32_TakeHypTrapException(0x03); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2().FMO == '1' then ICV_PMR() = R(t); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA64EL2) && !ELUsingAArch32(EL2) && HCR_EL2().IMO == '1' then ICV_PMR() = R(t); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR().FMO == '1' then ICV_PMR() = R(t); elsif EL2Enabled() && IsFeatureImplemented(FEAT_AA32EL2) && ELUsingAArch32(EL2) && HCR().IMO == '1' then ICV_PMR() = R(t); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x03); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR().[IRQ,FIQ] == '11' then Undefined(); else ICC_PMR() = R(t); end; elsif PSTATE.EL == EL2 then if ICC_HSRE().SRE == '0' then Undefined(); elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA64EL3) && !ELUsingAArch32(EL3) && SCR_EL3().[IRQ,FIQ] == '11' then if EL3SDDUndef() then Undefined(); else AArch64_AArch32SystemAccessTrap(EL3, 0x03); end; elsif HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL3) && ELUsingAArch32(EL3) && SCR().[IRQ,FIQ] == '11' then Undefined(); else ICC_PMR() = R(t); end; elsif PSTATE.EL == EL3 then if ICC_MSRE().SRE == '0' then Undefined(); elsif SCR().[IRQ,FIQ] == '11' && PSTATE.M != M32_Monitor then Undefined(); else ICC_PMR() = R(t); end; end;
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