ICV_AP1R<n>, Interrupt Controller Virtual Active Priorities Group 1 Registers, n = 0 - 3

Accessing ICV_AP1R<n>

Writing to these registers with any value other than the last read value of the register (or 0x00000000 when there are no Group 1 active priorities) might result in UNPREDICTABLE behavior of the virtual interrupt prioritization system, causing:

• Interrupts that should preempt execution to not preempt execution.
• Interrupts that should not preempt execution to preempt execution.

ICV_AP1R1 is implemented only in implementations that support 6 or more bits of priority. ICV_AP1R2 and ICV_AP1R3 are implemented only in implementations that support 7 bits of priority. Unimplemented registers are UNDEFINED.

Writing to the active priority registers in any order other than the following order might result in UNPREDICTABLE behavior of the interrupt prioritization system:

• ICV_AP0R<n>.
• ICV_AP1R<n>.

Accesses to this register use the following encodings in the System register encoding space:

MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>} ; Where m = 0-3

coproc	opc1	CRn	CRm	opc2
0b1111	0b000	0b1100	0b1001	0b0:m[1:0]

integer m = UInt(opc2<1:0>); if m == 1 && NUM_GIC_PRIORITY_BITS < 6 then UNDEFINED; elsif (m == 2 || m == 3) && NUM_GIC_PRIORITY_BITS < 7 then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && SCR_EL3.IRQ == '1' then UNDEFINED; elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR.IRQ == '1' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T12 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T12 == '1' then AArch32.TakeHypTrapException(0x03); elsif ICC_SRE.SRE == '0' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && ICH_HCR_EL2.TALL1 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && ICH_HCR.TALL1 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.IMO == '1' then R[t] = ICV_AP1R[m]; elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.IMO == '1' then R[t] = ICV_AP1R[m]; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.IRQ == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR.IRQ == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch32.TakeMonitorTrapException(); elsif HaveEL(EL3) then R[t] = ICC_AP1R_NS[m]; else R[t] = ICC_AP1R[m]; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && SCR_EL3.IRQ == '1' then UNDEFINED; elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && ELUsingAArch32(EL3) && SCR.IRQ == '1' then UNDEFINED; elsif ICC_HSRE.SRE == '0' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.IRQ == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && ELUsingAArch32(EL3) && SCR.IRQ == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch32.TakeMonitorTrapException(); elsif HaveEL(EL3) then R[t] = ICC_AP1R_NS[m]; else R[t] = ICC_AP1R[m]; elsif PSTATE.EL == EL3 then if ICC_MSRE.SRE == '0' then UNDEFINED; else if SCR.NS == '0' then R[t] = ICC_AP1R_S[m]; else R[t] = ICC_AP1R_NS[m];

MCR{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>} ; Where m = 0-3

coproc	opc1	CRn	CRm	opc2
0b1111	0b000	0b1100	0b1001	0b0:m[1:0]

integer m = UInt(opc2<1:0>); if m == 1 && NUM_GIC_PRIORITY_BITS < 6 then UNDEFINED; elsif (m == 2 || m == 3) && NUM_GIC_PRIORITY_BITS < 7 then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && SCR_EL3.IRQ == '1' then UNDEFINED; elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR.IRQ == '1' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T12 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T12 == '1' then AArch32.TakeHypTrapException(0x03); elsif ICC_SRE.SRE == '0' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && ICH_HCR_EL2.TALL1 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && ICH_HCR.TALL1 == '1' then AArch32.TakeHypTrapException(0x03); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.IMO == '1' then ICV_AP1R[m] = R[t]; elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.IMO == '1' then ICV_AP1R[m] = R[t]; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.IRQ == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR.IRQ == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch32.TakeMonitorTrapException(); elsif HaveEL(EL3) then ICC_AP1R_NS[m] = R[t]; else ICC_AP1R[m] = R[t]; elsif PSTATE.EL == EL2 then if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && SCR_EL3.IRQ == '1' then UNDEFINED; elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && ELUsingAArch32(EL3) && SCR.IRQ == '1' then UNDEFINED; elsif ICC_HSRE.SRE == '0' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.IRQ == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch64.AArch32SystemAccessTrap(EL3, 0x03); elsif HaveEL(EL3) && ELUsingAArch32(EL3) && SCR.IRQ == '1' then if Halted() && EDSCR.SDD == '1' then UNDEFINED; else AArch32.TakeMonitorTrapException(); elsif HaveEL(EL3) then ICC_AP1R_NS[m] = R[t]; else ICC_AP1R[m] = R[t]; elsif PSTATE.EL == EL3 then if ICC_MSRE.SRE == '0' then UNDEFINED; else if SCR.NS == '0' then ICC_AP1R_S[m] = R[t]; else ICC_AP1R_NS[m] = R[t];