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ERRSELR_EL1

ERRSELR_EL1, Error Record Select Register

The ERRSELR_EL1 characteristics are:

Purpose

Selects an error record to be accessed through the Error Record System registers.

Configuration

AArch64 System register ERRSELR_EL1 bits [31:0] are architecturally mapped to AArch32 System register ERRSELR[31:0].

This register is present only when FEAT_RAS is implemented. Otherwise, direct accesses to ERRSELR_EL1 are UNDEFINED.

If ERRIDR_EL1 indicates that zero error records are implemented, then it is IMPLEMENTATION DEFINED whether ERRSELR_EL1 is UNDEFINED or RES0.

Attributes

ERRSELR_EL1 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
RES0SEL

Bits [63:16]

Reserved, RES0.

SEL, bits [15:0]

Selects the error record accessed through the ERX registers.

For example, if ERRSELR_EL1.SEL is 0x0004, then direct reads and writes of ERXSTATUS_EL1 access ERR4STATUS.

If ERRSELR_EL1.SEL is greater than or equal to ERRIDR_EL1.NUM, then all of the following apply:

The reset behavior of this field is:

Accessing ERRSELR_EL1

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

MRS <Xt>, ERRSELR_EL1

op0op1CRnCRmop2
0b110b0000b01010b00110b001

if !IsFeatureImplemented(FEAT_RAS) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3().TERR == '1' then Undefined(); elsif EL2Enabled() && HCR_EL2().TERR == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HFGRTR_EL2().ERRSELR_EL1 == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3().TERR == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = ERRSELR_EL1(); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3().TERR == '1' then Undefined(); elsif HaveEL(EL3) && SCR_EL3().TERR == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else X{64}(t) = ERRSELR_EL1(); end; elsif PSTATE.EL == EL3 then X{64}(t) = ERRSELR_EL1(); end;

MSR ERRSELR_EL1, <Xt>

op0op1CRnCRmop2
0b110b0000b01010b00110b001

if !IsFeatureImplemented(FEAT_RAS) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3().TERR == '1' then Undefined(); elsif HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3().TWERR == '1' then Undefined(); elsif EL2Enabled() && HCR_EL2().TERR == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HFGWTR_EL2().ERRSELR_EL1 == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && SCR_EL3().TERR == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif HaveEL(EL3) && SCR_EL3().TWERR == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else ERRSELR_EL1() = X{64}(t); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3().TERR == '1' then Undefined(); elsif HaveEL(EL3) && EL3SDDUndefPriority() && SCR_EL3().TWERR == '1' then Undefined(); elsif HaveEL(EL3) && SCR_EL3().TERR == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif HaveEL(EL3) && SCR_EL3().TWERR == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; else ERRSELR_EL1() = X{64}(t); end; elsif PSTATE.EL == EL3 then ERRSELR_EL1() = X{64}(t); end;


2026-03-26 20:27:25, 2026-03_rel

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