B1.93 L2 Extended Control Register

The L2ECTLR characteristics are:

Purpose
Provides additional implementation defined control options for the L2 memory system. This register is used for dynamically changing, but implementation specific, control bits.
Usage constraints

This register is accessible as follows:

EL0

(NS)

EL0

(S)

EL1

(NS)

EL1

(S)

EL2

EL3

(SCR.NS = 1)

EL3

(SCR.NS = 0)

- - RW RW RW RW RW

The L2ECTLR can be written dynamically.

Configurations

There is one copy of this register that is used in both Secure and Non-secure states.

There is one L2ECTLR for the Cortex®‑A32 processor.

Attributes
L2ECTLR is a 32-bit register.
Figure B1-47 L2ECTLR bit assignments
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[31]

Reserved, res0.

L2 internal asynchronous error, [30]

L2 internal asynchronous error caused by L2 RAM double-bit ECC error. The possible values are:

0No pending asynchronous error. This is the reset value.
1An asynchronous error has occurred.

A write of 0 clears this bit. A write of 1 is ignored.

AXI, ACE, or CHI asynchronous error, [29]

AXI, ACE, or CHI asynchronous error indication. The possible values are:

0No pending asynchronous error.
1An asynchronous error has occurred.

A write of 0 clears this bit. A write of 1 is ignored.

[28:3]

Reserved, res0.

L2 dynamic retention control, [2:0]

L2 dynamic retention control. The possible values are:

0b000L2 dynamic retention disabled. This is the reset value.
0b0012 Generic Timer ticks required before retention entry.
0b0108 Generic Timer ticks required before retention entry.
0b01132 Generic Timer ticks required before retention entry.
0b10064 Generic Timer ticks required before retention entry.
0b101128 Generic Timer ticks required before retention entry.
0b110256 Generic Timer ticks required before retention entry.
0b111512 Generic Timer ticks required before retention entry.

To access the L2ECTLR:

MRC p15, 1, <Rt>, c9, c0, 3; Read L2ECTLR into Rt
MCR p15, 1, <Rt>, c9, c0, 3; Write Rt to L2ECTLR

Register access is encoded as follows:

Table B1-74 L2ECTLR access encoding

coproc opc1 CRn CRm opc2
1111 001 1001 0000 011
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