LORegion End Address (EL1)
Holds the physical address of the end of the LORegion described in the current LORegion descriptor selected by LORC_EL1.DS.
This register is present only when FEAT_LOR is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to LOREA_EL1 are UNDEFINED.
This register is RES0 if any of the following apply:
LOREA_EL1 is a 64-bit register.
| 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 |
| RES0 | EA[55:52] | EA[51:48] | EA[47:16] | ||||||||||||||||||||||||||||
| EA[47:16] | RES0 | ||||||||||||||||||||||||||||||
Any of the fields in this register are permitted to be cached in a TLB.
Reserved, RES0.
Extension to EA[47:16]. For more information, see EA[47:16].
The reset behavior of this field is:
Reserved, RES0.
Extension to EA[47:16]. For more information, see EA[47:16].
The reset behavior of this field is:
Reserved, RES0.
Bits [47:16] of the end physical address of an LORegion described in the current LORegion descriptor selected by LORC_EL1.DS. Bits[15:0] of this address are 0xFFFF. For implementations with fewer than 48 bits, the upper bits of this field are RES0.
When FEAT_LPA is implemented and 52-bit addresses are in use, EA[51:48] form bits [51:48] of the end physical address of the LORegion. Otherwise, when 52-bit addresses are not in use, EA[51:48] is RES0.
The reset behavior of this field is:
Reserved, RES0.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, LOREA_EL1
(op0 = 0b11, op1 = 0b000, CRn = 0b1010, CRm = 0b0100, op2 = 0b001)
if !(IsFeatureImplemented(FEAT_LOR) && IsFeatureImplemented(FEAT_AA64)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.TLOR == '1' then UNDEFINED; elsif HaveEL(EL3) && SCR_EL3.NS == '0' then UNDEFINED; elsif EL2Enabled() && HCR_EL2.TLOR == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HFGRTR_EL2.LOREA_EL1 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3.TLOR == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = LOREA_EL1; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && SCR_EL3.NS == '0' then UNDEFINED; elsif HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.TLOR == '1' then UNDEFINED; elsif HaveEL(EL3) && SCR_EL3.TLOR == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = LOREA_EL1; elsif PSTATE.EL == EL3 then if SCR_EL3.NS == '0' then UNDEFINED; else X[t, 64] = LOREA_EL1;
MSR LOREA_EL1, <Xt>
(op0 = 0b11, op1 = 0b000, CRn = 0b1010, CRm = 0b0100, op2 = 0b001)
if !(IsFeatureImplemented(FEAT_LOR) && IsFeatureImplemented(FEAT_AA64)) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.TLOR == '1' then UNDEFINED; elsif HaveEL(EL3) && SCR_EL3.NS == '0' then UNDEFINED; elsif EL2Enabled() && HCR_EL2.TLOR == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HFGWTR_EL2.LOREA_EL1 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3.TLOR == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else LOREA_EL1 = X[t, 64]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && SCR_EL3.NS == '0' then UNDEFINED; elsif HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.TLOR == '1' then UNDEFINED; elsif HaveEL(EL3) && SCR_EL3.TLOR == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else LOREA_EL1 = X[t, 64]; elsif PSTATE.EL == EL3 then if SCR_EL3.NS == '0' then UNDEFINED; else LOREA_EL1 = X[t, 64];
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