CurrentEL, Current Exception Level

The CurrentEL characteristics are:

Purpose

Holds the current Exception level.

Configuration

There are no configuration notes.

Attributes

CurrentEL is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
RES0ELRES0

Bits [63:4]

Reserved, RES0.

EL, bits [3:2]

Current Exception level.

ELMeaning
0b00

EL0.

0b01

EL1.

0b10

EL2.

0b11

EL3.

When the HCR_EL2.NV bit is 1, EL1 read accesses to the CurrentEL register return the value of 0b10 in this field.

This field resets to the highest implemented Exception level.

Bits [1:0]

Reserved, RES0.

Accessing CurrentEL

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

MRS <Xt>, CurrentEL

op0op1CRnCRmop2
0b110b0000b01000b00100b010

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.NV == '1' then return Zeros(60):'10':Zeros(2); else return Zeros(60):PSTATE.EL:Zeros(2); elsif PSTATE.EL == EL2 then return Zeros(60):PSTATE.EL:Zeros(2); elsif PSTATE.EL == EL3 then return Zeros(60):PSTATE.EL:Zeros(2);


30/09/2021 15:34; 092b4e1bbfbb45a293b198f9330c5f529ead2b0f

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