The LORC_EL1 characteristics are:
Enables and disables LORegions, and selects the current LORegion descriptor.
This register is present only from Armv8.1. Otherwise, direct accesses to LORC_EL1 are UNDEFINED.
If no LORegion descriptors are supported by the PE, then this register is RES0.
Some or all RW fields of this register have defined reset values. These apply only if the PE resets into an Exception level that is using AArch64. Otherwise, RW fields in this register reset to architecturally UNKNOWN values.
LORC_EL1 is a 64-bit register.
The LORC_EL1 bit assignments are:
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 |
RES0 | |||||||||||||||||||||||||||||||
RES0 | DS | RES0 | EN | ||||||||||||||||||||||||||||
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 |
Reserved, RES0.
Descriptor Select. Selects the current LORegion descriptor accessed by LORSA_EL1, LOREA_EL1, and LORN_EL1.
The number of LORegion descriptors in IMPLEMENTATION DEFINED. The maximum number of LORegion descriptors supported is 256. If the number is less than 256, then bits[63:M+2] are RES0, where M is Log2(Number of LORegion descriptors supported by the implementation).
If this field points to an LORegion descriptor that is not supported by an implementation, then the registers LORN_EL1, LOREA_EL1, and LORSA_EL1 are RES0.
This field resets to an architecturally UNKNOWN value.
Reserved, RES0.
Reserved, RES0.
Enable. Indicates whether LORegions are enabled.
EN | Meaning |
---|---|
0b0 |
Disabled. Memory accesses do not match any LORegions. |
0b1 |
Enabled. Memory accesses may match a LORegion. |
This bit is permitted to be cached in a TLB.
This field resets to 0.
Reserved, RES0.
Accesses to this register use the following encodings:
op0 | op1 | CRn | CRm | op2 |
---|---|---|---|---|
0b11 | 0b000 | 0b1010 | 0b0100 | 0b011 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if SCR_EL3.NS == '0' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TLOR == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.TLOR == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else return LORC_EL1; elsif PSTATE.EL == EL2 then if SCR_EL3.NS == '0' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.TLOR == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else return LORC_EL1; elsif PSTATE.EL == EL3 then if SCR_EL3.NS == '0' then UNDEFINED; else return LORC_EL1;
op0 | op1 | CRn | CRm | op2 |
---|---|---|---|---|
0b11 | 0b000 | 0b1010 | 0b0100 | 0b011 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if SCR_EL3.NS == '0' then UNDEFINED; elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TLOR == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.TLOR == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else LORC_EL1 = X[t]; elsif PSTATE.EL == EL2 then if SCR_EL3.NS == '0' then UNDEFINED; elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.TLOR == '1' then AArch64.SystemAccessTrap(EL3, 0x18); else LORC_EL1 = X[t]; elsif PSTATE.EL == EL3 then if SCR_EL3.NS == '0' then UNDEFINED; else LORC_EL1 = X[t];
27/03/2019 21:59; e5e4db499bf9867a4b93324c4dbac985d3da9376
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