CID_EL0, Compartment ID Register

The CID_EL0 characteristics are:

Purpose

Provides a number that can be used to separate out different context numbers with each Exception level.

Configuration

This register is present only when Morello is implemented. Otherwise, direct accesses to CID_EL0 are UNDEFINED.

RW fields in this register reset to architecturally UNKNOWN values.

Attributes

CID_EL0 is a 129-bit register.

Field descriptions

The CID_EL0 bit assignments are:

Bits [128:0]

Compartment ID

This field resets to an architecturally UNKNOWN value.

Accessing the CID_EL0

Accesses to this register use the following encodings:

MRS <Ct>, CID_EL0

op0op1CRnCRmop2
0b110b0110b11010b00000b111

if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && !(EL2Enabled() && HCR_EL2.<E2H,TGE> == '11') && CPACR_EL1.CEN != '11' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.SystemAccessTrap(EL2, 0x29); else AArch64.SystemAccessTrap(EL1, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && CPTR_EL2.CEN != '11' then AArch64.SystemAccessTrap(EL2, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H != '1' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return CID_EL0; elsif PSTATE.EL == EL1 then if CPACR_EL1.CEN == 'x0' then AArch64.SystemAccessTrap(EL1, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H != '1' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return CID_EL0; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '0' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return CID_EL0; elsif PSTATE.EL == EL3 then if CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return CID_EL0;

MSR CID_EL0, <Ct>

op0op1CRnCRmop2
0b110b0110b11010b00000b111

if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && !(EL2Enabled() && HCR_EL2.<E2H,TGE> == '11') && CPACR_EL1.CEN != '11' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.SystemAccessTrap(EL2, 0x29); else AArch64.SystemAccessTrap(EL1, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && CPTR_EL2.CEN != '11' then AArch64.SystemAccessTrap(EL2, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H != '1' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else CID_EL0 = C[t]; elsif PSTATE.EL == EL1 then if CPACR_EL1.CEN == 'x0' then AArch64.SystemAccessTrap(EL1, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H != '1' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else CID_EL0 = C[t]; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '0' && CPTR_EL2.TC == '1' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HCR_EL2.E2H == '1' && CPTR_EL2.CEN == 'x0' then AArch64.SystemAccessTrap(EL2, 0x29); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else CID_EL0 = C[t]; elsif PSTATE.EL == EL3 then if CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else CID_EL0 = C[t];




12/01/2022 09:56; 05a4944b4b04e7ab50def8c126b479d22136f35b

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