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APGAKeyHi_EL1: Pointer Authentication Key A for Code (bits[127:64])

Purpose

Holds bits[127:64] of key used for generic pointer authentication code.

Note

The term APGAKey_EL1 is used to describe the concatenation of APGAKeyHi_EL1: APGAKeyLo_EL1.

Configuration

This register is present only when FEAT_PAuth is implemented. Otherwise, direct accesses to APGAKeyHi_EL1 are UNDEFINED.

Attributes

APGAKeyHi_EL1 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
64 bit value, bits[127:64] of the 128 bit pointer authentication key value
64 bit value, bits[127:64] of the 128 bit pointer authentication key value

Bits [63:0]

64 bit value, bits[127:64] of the 128 bit pointer authentication key value.

The reset behavior of this field is:

Accessing APGAKeyHi_EL1

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

MRS <Xt>, APGAKeyHi_EL1

op0op1CRnCRmop2
0b110b0000b00100b00110b001

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.APK == '0' then UNDEFINED; elsif EL2Enabled() && HCR_EL2.APK == '0' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HFGRTR_EL2.APGAKey == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3.APK == '0' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = APGAKeyHi_EL1; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.APK == '0' then UNDEFINED; elsif HaveEL(EL3) && SCR_EL3.APK == '0' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = APGAKeyHi_EL1; elsif PSTATE.EL == EL3 then X[t, 64] = APGAKeyHi_EL1;

MSR APGAKeyHi_EL1, <Xt>

op0op1CRnCRmop2
0b110b0000b00100b00110b001

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.APK == '0' then UNDEFINED; elsif EL2Enabled() && HCR_EL2.APK == '0' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HFGWTR_EL2.APGAKey == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3.APK == '0' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else APGAKeyHi_EL1 = X[t, 64]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3.APK == '0' then UNDEFINED; elsif HaveEL(EL3) && SCR_EL3.APK == '0' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); else APGAKeyHi_EL1 = X[t, 64]; elsif PSTATE.EL == EL3 then APGAKeyHi_EL1 = X[t, 64];