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ERRIDR_EL1

ERRIDR_EL1, Error Record ID Register

The ERRIDR_EL1 characteristics are:

Purpose

Defines the highest numbered index of the error records that can be accessed through the Error Record System registers.

Configuration

AArch64 System register ERRIDR_EL1 bits [31:0] are architecturally mapped to AArch32 System register ERRIDR[31:0].

This register is present only when FEAT_RAS is implemented. Otherwise, direct accesses to ERRIDR_EL1 are UNDEFINED.

Attributes

ERRIDR_EL1 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
RES0NUM

Bits [63:16]

Reserved, RES0.

NUM, bits [15:0]

Highest numbered index of the records that can be accessed through the Error Record System registers plus one. Zero indicates no records can be accessed through the Error Record System registers.

Each implemented record is owned by a node. A node might own multiple records.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Accessing ERRIDR_EL1

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

MRS <Xt>, ERRIDR_EL1

op0op1CRnCRmop2
0b110b0000b01010b00110b000

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().ERRIDR_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) = ERRIDR_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) = ERRIDR_EL1(); end; elsif PSTATE.EL == EL3 then X{64}(t) = ERRIDR_EL1(); end;


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

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