IMPLEMENTATION DEFINED Registers
This area of the instruction set space is reserved for IMPLEMENTATION DEFINED registers.
This register is present only when FEAT_AA64 is implemented. Otherwise, direct accesses to S3_<op1>_<Cn>_<Cm>_<op2> are UNDEFINED.
When FEAT_SYSREG128 is implemented, each register in this space is a 128-bit register that can also be accessed as a 64-bit value. If it is accessed as a 64-bit register, accesses read and write bits [63:0] and do not modify bits [127:64].
S3_<op1>_<Cn>_<Cm>_<op2> is a:
| 127 | 126 | 125 | 124 | 123 | 122 | 121 | 120 | 119 | 118 | 117 | 116 | 115 | 114 | 113 | 112 | 111 | 110 | 109 | 108 | 107 | 106 | 105 | 104 | 103 | 102 | 101 | 100 | 99 | 98 | 97 | 96 |
| IMPLEMENTATION DEFINED | |||||||||||||||||||||||||||||||
| 95 | 94 | 93 | 92 | 91 | 90 | 89 | 88 | 87 | 86 | 85 | 84 | 83 | 82 | 81 | 80 | 79 | 78 | 77 | 76 | 75 | 74 | 73 | 72 | 71 | 70 | 69 | 68 | 67 | 66 | 65 | 64 |
| IMPLEMENTATION DEFINED | |||||||||||||||||||||||||||||||
| 63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |
| IMPLEMENTATION DEFINED | |||||||||||||||||||||||||||||||
| 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 |
| IMPLEMENTATION DEFINED | |||||||||||||||||||||||||||||||
IMPLEMENTATION DEFINED.
| 63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |
| 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 |
| IMPLEMENTATION DEFINED | |||||||||||||||||||||||||||||||
| IMPLEMENTATION DEFINED | |||||||||||||||||||||||||||||||
IMPLEMENTATION DEFINED.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, S3_<op1>_C<Cn>_C<Cm>_<op2>
(op0 = 0b11, op1 = op1[2:0], CRn = 0b1x11, CRm = Cm[3:0], op2 = op2[2:0])
if !IsFeatureImplemented(FEAT_AA64) then Undefined(); elsif PSTATE.EL == EL0 then if EffectivelyAtEL0NotInHost() && SCTLR_EL1().TIDCP == '1' then AArch64_SystemAccessTraptoEL1orEL2(0x18); elsif EffectivelyAtEL0InHost() && SCTLR_EL2().TIDCP == '1' then AArch64_SystemAccessTrap(EL2, 0x18); else AArch64_ImpDefSysRegRead(op0, op1, CRn, CRm, op2, t); end; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2().TIDCP == '1' then AArch64_SystemAccessTrap(EL2, 0x18); else AArch64_ImpDefSysRegRead(op0, op1, CRn, CRm, op2, t); end; elsif PSTATE.EL == EL2 then AArch64_ImpDefSysRegRead(op0, op1, CRn, CRm, op2, t); elsif PSTATE.EL == EL3 then AArch64_ImpDefSysRegRead(op0, op1, CRn, CRm, op2, t); end;
MSR S3_<op1>_C<Cn>_C<Cm>_<op2>, <Xt>
(op0 = 0b11, op1 = op1[2:0], CRn = 0b1x11, CRm = Cm[3:0], op2 = op2[2:0])
if !IsFeatureImplemented(FEAT_AA64) then Undefined(); elsif PSTATE.EL == EL0 then if EffectivelyAtEL0NotInHost() && SCTLR_EL1().TIDCP == '1' then AArch64_SystemAccessTraptoEL1orEL2(0x18); elsif EffectivelyAtEL0InHost() && SCTLR_EL2().TIDCP == '1' then AArch64_SystemAccessTrap(EL2, 0x18); else AArch64_ImpDefSysRegWrite(op0, op1, CRn, CRm, op2, t); end; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2().TIDCP == '1' then AArch64_SystemAccessTrap(EL2, 0x18); else AArch64_ImpDefSysRegWrite(op0, op1, CRn, CRm, op2, t); end; elsif PSTATE.EL == EL2 then AArch64_ImpDefSysRegWrite(op0, op1, CRn, CRm, op2, t); elsif PSTATE.EL == EL3 then AArch64_ImpDefSysRegWrite(op0, op1, CRn, CRm, op2, t); end;
MRRS <Xt>, <Xt+1>, S3_<op1>_C<Cn>_C<Cm>_<op2>
(op0 = 0b11, op1 = op1[2:0], CRn = 0b1x11, CRm = Cm[3:0], op2 = op2[2:0])
if !IsFeatureImplemented(FEAT_AA64) then Undefined(); elsif HaveEL(EL3) && PSTATE.EL != EL3 && EL3SDDUndefPriority() && SCR_EL3().EnIDCP128 == '0' then Undefined(); elsif PSTATE.EL == EL0 then if EffectivelyAtEL0NotInHost() && SCTLR_EL1().TIDCP == '1' then AArch64_SystemAccessTraptoEL1orEL2(0x14); elsif EffectivelyAtEL0InHost() && SCTLR_EL2().TIDCP == '1' then AArch64_SystemAccessTrap(EL2, 0x14); elsif EffectivelyAtEL0NotInHost() && (!IsSCTLR2EL1Enabled() || SCTLR2_EL1().EnIDCP128 == '0') then AArch64_SystemAccessTraptoEL1orEL2(0x14); elsif EffectivelyAtEL0InHost() && (!IsSCTLR2EL2Enabled() || SCTLR2_EL2().EnIDCP128 == '0') then AArch64_SystemAccessTrap(EL2, 0x14); elsif EL2Enabled() && EffectivelyAtEL0NotInHost() && (!IsHCRXEL2Enabled() || HCRX_EL2().EnIDCP128 == '0') then AArch64_SystemAccessTrap(EL2, 0x14); elsif HaveEL(EL3) && SCR_EL3().EnIDCP128 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else AArch64_ImpDefSysRegRead128(op0, op1, CRn, CRm, op2, t, t2); end; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2().TIDCP == '1' then AArch64_SystemAccessTrap(EL2, 0x14); elsif EL2Enabled() && (!IsHCRXEL2Enabled() || HCRX_EL2().EnIDCP128 == '0') then AArch64_SystemAccessTrap(EL2, 0x14); elsif HaveEL(EL3) && SCR_EL3().EnIDCP128 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else AArch64_ImpDefSysRegRead128(op0, op1, CRn, CRm, op2, t, t2); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && SCR_EL3().EnIDCP128 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else AArch64_ImpDefSysRegRead128(op0, op1, CRn, CRm, op2, t, t2); end; elsif PSTATE.EL == EL3 then AArch64_ImpDefSysRegRead128(op0, op1, CRn, CRm, op2, t, t2); end;
MSRR S3_<op1>_C<Cn>_C<Cm>_<op2>, <Xt>, <Xt+1>
(op0 = 0b11, op1 = op1[2:0], CRn = 0b1x11, CRm = Cm[3:0], op2 = op2[2:0])
if !IsFeatureImplemented(FEAT_AA64) then Undefined(); elsif HaveEL(EL3) && PSTATE.EL != EL3 && EL3SDDUndefPriority() && SCR_EL3().EnIDCP128 == '0' then Undefined(); elsif PSTATE.EL == EL0 then if EffectivelyAtEL0NotInHost() && SCTLR_EL1().TIDCP == '1' then AArch64_SystemAccessTraptoEL1orEL2(0x14); elsif EffectivelyAtEL0InHost() && SCTLR_EL2().TIDCP == '1' then AArch64_SystemAccessTrap(EL2, 0x14); elsif EffectivelyAtEL0NotInHost() && (!IsSCTLR2EL1Enabled() || SCTLR2_EL1().EnIDCP128 == '0') then AArch64_SystemAccessTraptoEL1orEL2(0x14); elsif EffectivelyAtEL0InHost() && (!IsSCTLR2EL2Enabled() || SCTLR2_EL2().EnIDCP128 == '0') then AArch64_SystemAccessTrap(EL2, 0x14); elsif EL2Enabled() && EffectivelyAtEL0NotInHost() && (!IsHCRXEL2Enabled() || HCRX_EL2().EnIDCP128 == '0') then AArch64_SystemAccessTrap(EL2, 0x14); elsif HaveEL(EL3) && SCR_EL3().EnIDCP128 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else AArch64_ImpDefSysRegWrite128(op0, op1, CRn, CRm, op2, t, t2); end; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2().TIDCP == '1' then AArch64_SystemAccessTrap(EL2, 0x14); elsif EL2Enabled() && (!IsHCRXEL2Enabled() || HCRX_EL2().EnIDCP128 == '0') then AArch64_SystemAccessTrap(EL2, 0x14); elsif HaveEL(EL3) && SCR_EL3().EnIDCP128 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else AArch64_ImpDefSysRegWrite128(op0, op1, CRn, CRm, op2, t, t2); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && SCR_EL3().EnIDCP128 == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else AArch64_ImpDefSysRegWrite128(op0, op1, CRn, CRm, op2, t, t2); end; elsif PSTATE.EL == EL3 then AArch64_ImpDefSysRegWrite128(op0, op1, CRn, CRm, op2, t, t2); end;
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