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LOREA_EL1: LORegion End Address (EL1)

Purpose

Holds the physical address of the end of the LORegion described in the current LORegion descriptor selected by LORC_EL1.DS.

Configuration

This register is present only when FEAT_LOR is implemented. Otherwise, direct accesses to LOREA_EL1 are UNDEFINED.

This register is RES0 if any of the following apply:

Attributes

LOREA_EL1 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0EA[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.

Bits [63:56]

Reserved, RES0.

EA[55:52], bits [55:52]

When FEAT_D128 is implemented:

Extension to EA[47:16]. For more information, see EA[47:16].

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

EA[51:48], bits [51:48]

When FEAT_LPA is implemented:

Extension to EA[47:16]. For more information, see EA[47:16].

The reset behavior of this field is:



Otherwise:

Reserved, RES0.

EA[47:16], bits [47:16]

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:

Bits [15:0]

Reserved, RES0.

Accessing LOREA_EL1

Accesses to this register use the following encodings in the System register encoding space:

MRS <Xt>, LOREA_EL1

op0op1CRnCRmop2
0b110b0000b10100b01000b001

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.TLOR == '1' then UNDEFINED; elsif 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 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>

op0op1CRnCRmop2
0b110b0000b10100b01000b001

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.TLOR == '1' then UNDEFINED; elsif 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 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];