ELR_EL3, Exception Link Register (EL3)

The ELR_EL3 characteristics are:

Purpose

When taking an exception to EL3, holds the address to return to.

Configuration

RW fields in this register reset to architecturally UNKNOWN values.

Attributes

ELR_EL3 is a 64-bit register.

Field descriptions

The ELR_EL3 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
Return address
Return address
313029282726252423222120191817161514131211109876543210

Bits [63:0]

Return address.

An exception return from EL3 using AArch64 makes ELR_EL3 become UNKNOWN.

This field resets to an architecturally UNKNOWN value.

Accessing the ELR_EL3

Accesses to this register use the following encodings:

MRS <Xt>, ELR_EL3

op0CRnop1op2CRm
0b110b01000b1100b0010b0000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then return ELR_EL3;

MSR ELR_EL3, <Xt>

op0CRnop1op2CRm
0b110b01000b1100b0010b0000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then ELR_EL3 = X[t];




13/12/2018 16:42; 6379d01c197f1d40720d32d0f84c419c9187c009

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