ICC_RPR_EL1, Interrupt Controller Running Priority Register

The ICC_RPR_EL1 characteristics are:

Purpose

Indicates the Running priority of the CPU interface.

Configuration

AArch64 System register ICC_RPR_EL1 performs the same function as AArch32 System register ICC_RPR.

Attributes

ICC_RPR_EL1 is a 64-bit register.

Field descriptions

The ICC_RPR_EL1 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
00000000000000000000000000000000
000000000000000000000000Priority
313029282726252423222120191817161514131211109876543210

Bits [63:8]

Reserved, RES0.

Priority, bits [7:0]

The current running priority on the CPU interface. This is the group priority of the current active interrupt.

If there are no active interrupts on the CPU interface, or all active interrupts have undergone a priority drop, the value returned is the Idle priority.

The priority returned is the group priority as if the BPR for the current Exception level and Security state was set to the minimum value of BPR for the number of implemented priority bits.

Note

If 8 bits of priority are implemented the group priority is bits[7:1] of the priority.

Accessing the ICC_RPR_EL1

Software cannot determine the number of implemented priority bits from a read of this register.

Accesses to this register use the following encodings:

MRS <Xt>, ICC_RPR_EL1

op0CRnop1op2CRm
0b110b11000b0000b0110b1011

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if ICC_SRE_EL1.SRE == '0' then AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && ICH_HCR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.FMO == '1' then return ICV_RPR_EL1; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.IMO == '1' then return ICV_RPR_EL1; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.<IRQ,FIQ> == '11' then AArch64.SystemAccessTrap(EL3, 0x18); else return ICC_RPR_EL1; elsif PSTATE.EL == EL2 then if ICC_SRE_EL2.SRE == '0' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.<IRQ,FIQ> == '11' then AArch64.SystemAccessTrap(EL3, 0x18); else return ICC_RPR_EL1; elsif PSTATE.EL == EL3 then if ICC_SRE_EL3.SRE == '0' then AArch64.SystemAccessTrap(EL3, 0x18); else return ICC_RPR_EL1;




13/12/2018 16:42; 6379d01c197f1d40720d32d0f84c419c9187c009

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