AMAIR_EL1, Auxiliary Memory Attribute Indirection Register (EL1)

The AMAIR_EL1 characteristics are:

Purpose

Provides IMPLEMENTATION DEFINED memory attributes for the memory regions specified by MAIR_EL1.

Configuration

AArch64 System register AMAIR_EL1 bits [31:0] are architecturally mapped to AArch32 System register AMAIR0[31:0].

AArch64 System register AMAIR_EL1 bits [63:32] are architecturally mapped to AArch32 System register AMAIR1[31:0].

Attributes

AMAIR_EL1 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
IMPLEMENTATION DEFINED
IMPLEMENTATION DEFINED

AMAIR_EL1 is permitted to be cached in a TLB.

IMPLEMENTATION DEFINED, bits [63:0]

IMPLEMENTATION DEFINED.

The reset behavior of this field is:

Accessing AMAIR_EL1

When HCR_EL2.E2H is 1, without explicit synchronization, access from EL3 using the mnemonic AMAIR_EL1 or AMAIR_EL12 are not guaranteed to be ordered with respect to accesses using the other mnemonic.

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

MRS <Xt>, AMAIR_EL1

op0op1CRnCRmop2
0b110b0000b10100b00110b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.TRVM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HFGRTR_EL2.AMAIR_EL1 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && HCR_EL2.<NV2,NV1,NV> == '111' then X[t, 64] = NVMem[0x148]; else X[t, 64] = AMAIR_EL1; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then X[t, 64] = AMAIR_EL2; else X[t, 64] = AMAIR_EL1; elsif PSTATE.EL == EL3 then X[t, 64] = AMAIR_EL1;

MSR AMAIR_EL1, <Xt>

op0op1CRnCRmop2
0b110b0000b10100b00110b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.TVM == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HFGWTR_EL2.AMAIR_EL1 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && HCR_EL2.<NV2,NV1,NV> == '111' then NVMem[0x148] = X[t, 64]; else AMAIR_EL1 = X[t, 64]; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then AMAIR_EL2 = X[t, 64]; else AMAIR_EL1 = X[t, 64]; elsif PSTATE.EL == EL3 then AMAIR_EL1 = X[t, 64];

MRS <Xt>, AMAIR_EL12

op0op1CRnCRmop2
0b110b1010b10100b00110b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.<NV2,NV1,NV> == '101' then X[t, 64] = NVMem[0x148]; elsif EL2Enabled() && HCR_EL2.NV == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then X[t, 64] = AMAIR_EL1; else UNDEFINED; elsif PSTATE.EL == EL3 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' then X[t, 64] = AMAIR_EL1; else UNDEFINED;

MSR AMAIR_EL12, <Xt>

op0op1CRnCRmop2
0b110b1010b10100b00110b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.<NV2,NV1,NV> == '101' then NVMem[0x148] = X[t, 64]; elsif EL2Enabled() && HCR_EL2.NV == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then if HCR_EL2.E2H == '1' then AMAIR_EL1 = X[t, 64]; else UNDEFINED; elsif PSTATE.EL == EL3 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.E2H == '1' then AMAIR_EL1 = X[t, 64]; else UNDEFINED;


04/07/2023 11:22; 1b994cb0b8c6d1ae5a9a15edbc8bd6ce3b5c7d68

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