RSP_EL0, Restricted Stack Pointer

The RSP_EL0 characteristics are:

Purpose

Holds the stack pointer when the PE is in Restricted. This is used as the current stack pointer at all Exception levels when the PE is in Restricted.

Configuration

This register is present only when Morello is implemented. Otherwise, direct accesses to RSP_EL0 are UNDEFINED.

RW fields in this register reset to architecturally UNKNOWN values.

Attributes

RSP_EL0 is a 129-bit register.

Field descriptions

The RSP_EL0 bit assignments are:

Bits [128:0]

Capability stack pointer.

This field resets to an architecturally UNKNOWN value.

Accessing the RSP_EL0

When the PE is in Restricted, this register is accessible as the current stack pointer.

Accesses to this register use the following encodings:

MRS <Xt>, RSP_EL0

op0op1CRnCRmop2
0b110b1110b01000b00010b011

if PSTATE.EL == EL0 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif !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 RSP_EL0<63:0>; elsif PSTATE.EL == EL1 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif 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 RSP_EL0<63:0>; elsif PSTATE.EL == EL2 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif 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 RSP_EL0<63:0>; elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return RSP_EL0<63:0>;

MSR RSP_EL0, <Xt>

op0op1CRnCRmop2
0b110b1110b01000b00010b011

if PSTATE.EL == EL0 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif !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 RSP_EL0 = ZeroExtend(X[t]); elsif PSTATE.EL == EL1 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif 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 RSP_EL0 = ZeroExtend(X[t]); elsif PSTATE.EL == EL2 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif 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 RSP_EL0 = ZeroExtend(X[t]); elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else RSP_EL0 = ZeroExtend(X[t]);

MRS <Ct>, RCSP_EL0

op0op1CRnCRmop2
0b110b1110b01000b00010b011

if PSTATE.EL == EL0 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif !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 RSP_EL0; elsif PSTATE.EL == EL1 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif 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 RSP_EL0; elsif PSTATE.EL == EL2 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif 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 RSP_EL0; elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return RSP_EL0;

MSR RCSP_EL0, <Ct>

op0op1CRnCRmop2
0b110b1110b01000b00010b011

if PSTATE.EL == EL0 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif !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 RSP_EL0 = C[t]; elsif PSTATE.EL == EL1 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif 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 RSP_EL0 = C[t]; elsif PSTATE.EL == EL2 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif 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 RSP_EL0 = C[t]; elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && IsInRestricted() && !Halted() then UNDEFINED; elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else RSP_EL0 = C[t];




12/01/2022 09:56; 05a4944b4b04e7ab50def8c126b479d22136f35b

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