Read Check Write Instruction Mask (EL1)
Contains the mask used by RCW instructions.
This register is present only when FEAT_THE is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to RCWMASK_EL1 are UNDEFINED.
RCWMASK_EL1 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].
RCWMASK_EL1 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 |
| RCWMASK | |||||||||||||||||||||||||||||||
| 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 |
| RCWMASK | |||||||||||||||||||||||||||||||
| 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 |
| RCWMASK | |||||||||||||||||||||||||||||||
| 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 |
| RCWMASK | |||||||||||||||||||||||||||||||
Mask used to decide which bit-fields are writable to the 128-bit Descriptor by RCW or RCWS instructions.
If RCWMASK_EL1 is indirectly read by 128-bit variants of RCW or RCWS instructions:
The Effective value of RCWMASK[n] is the same as RCWMASK_EL1[n], except as follows:
If n >= 17, and n <= 55, the Effective value of RCWMASK[n] is the same as RCWMASK_EL1[16].
If n is in {126:125, 120:119, 114, 107:101, 90:56, 1:0}, the Effective value of RCWMASK[n] is 0.
If n >= 121, n <= 124, and FEAT_S1POE is not implemented, the Effective value of RCWMASK[n] is 0.
If FEAT_MEC is not implemented, the Effective value of RCWMASK[108] is 0.
If RCWMASK_EL1 is indirectly read by 64-bit variants of RCW or RCWS instructions:
The Effective value of RCWMASK[n] is the same as RCWMASK_EL1[n], except as follows:
RCWMASK_EL1 register bits {126:125, 120:119, 114, 107:101, 90:64, 52, 49:18, 0} are RES0.
If FEAT_S1POE is not implemented, RCWMASK_EL1 register bits {124:121} are RES0.
If FEAT_MEC is not implemented, RCWMASK_EL1[108] is RES0.
The reset behavior of this field is:
| 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 |
| RCWMASK | |||||||||||||||||||||||||||||||
| RCWMASK | |||||||||||||||||||||||||||||||
Mask used to decide which bit-fields are writable to the 64-bit Descriptor by RCW or RCWS Instructions.
The Effective value of RCWMASK[n] is the same as RCWMASK_EL1[n], except as follows:
RCWMASK_EL1 register bits {52, 49:18, 0} are RES0.
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, RCWMASK_EL1
(op0 = 0b11, op1 = 0b000, CRn = 0b1101, CRm = 0b0000, op2 = 0b110)
if !(IsFeatureImplemented(FEAT_THE) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && SCR_EL3().RCWMASKEn == '0' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HFGRTR_EL2().nRCWMASK_EL1 == '0' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3().RCWMASKEn == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = RCWMASK_EL1()[63:0]; end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && SCR_EL3().RCWMASKEn == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = RCWMASK_EL1()[63:0]; end; elsif PSTATE.EL == EL3 then X{64}(t) = RCWMASK_EL1()[63:0]; end;
MSR RCWMASK_EL1, <Xt>
(op0 = 0b11, op1 = 0b000, CRn = 0b1101, CRm = 0b0000, op2 = 0b110)
if !(IsFeatureImplemented(FEAT_THE) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && SCR_EL3().RCWMASKEn == '0' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HFGWTR_EL2().nRCWMASK_EL1 == '0' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3().RCWMASKEn == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else RCWMASK_EL1()[63:0] = X{64}(t); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && SCR_EL3().RCWMASKEn == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else RCWMASK_EL1()[63:0] = X{64}(t); end; elsif PSTATE.EL == EL3 then RCWMASK_EL1()[63:0] = X{64}(t); end;
MRRS <Xt>, <Xt+1>, RCWMASK_EL1
(op0 = 0b11, op1 = 0b000, CRn = 0b1101, CRm = 0b0000, op2 = 0b110)
if !(IsFeatureImplemented(FEAT_THE) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && SCR_EL3().RCWMASKEn == '0' then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && SCR_EL3().D128En == '0' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HFGRTR_EL2().nRCWMASK_EL1 == '0' then AArch64_SystemAccessTrap(EL2, 0x14); elsif EL2Enabled() && (!IsHCRXEL2Enabled() || HCRX_EL2().D128En == '0') then AArch64_SystemAccessTrap(EL2, 0x14); elsif HaveEL(EL3) && SCR_EL3().RCWMASKEn == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; elsif HaveEL(EL3) && SCR_EL3().D128En == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else X{128}(t, t2) = RCWMASK_EL1()[127:0]; end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && SCR_EL3().RCWMASKEn == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; elsif HaveEL(EL3) && SCR_EL3().D128En == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else X{128}(t, t2) = RCWMASK_EL1()[127:0]; end; elsif PSTATE.EL == EL3 then X{128}(t, t2) = RCWMASK_EL1()[127:0]; end;
MSRR RCWMASK_EL1, <Xt>, <Xt+1>
(op0 = 0b11, op1 = 0b000, CRn = 0b1101, CRm = 0b0000, op2 = 0b110)
if !(IsFeatureImplemented(FEAT_THE) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && SCR_EL3().RCWMASKEn == '0' then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && SCR_EL3().D128En == '0' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HFGWTR_EL2().nRCWMASK_EL1 == '0' then AArch64_SystemAccessTrap(EL2, 0x14); elsif EL2Enabled() && (!IsHCRXEL2Enabled() || HCRX_EL2().D128En == '0') then AArch64_SystemAccessTrap(EL2, 0x14); elsif HaveEL(EL3) && SCR_EL3().RCWMASKEn == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; elsif HaveEL(EL3) && SCR_EL3().D128En == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else RCWMASK_EL1()[127:0] = X{128}(t, t2); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && SCR_EL3().RCWMASKEn == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; elsif HaveEL(EL3) && SCR_EL3().D128En == '0' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x14); end; else RCWMASK_EL1()[127:0] = X{128}(t, t2); end; elsif PSTATE.EL == EL3 then RCWMASK_EL1()[127:0] = X{128}(t, t2); end;
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