zephyr,retention

Vendor: Zephyr-specific binding

Note

An implementation of a driver matching this compatible is available in subsys/retention/retention.c.

Description

Retention subsystem area, which has a retained memory parent. Example
64-byte area with 2-byte prefix and 1-byte checksum with 61 usable bytes
for user storage:

sram@2003FFC0 {
  compatible = "zephyr,memory-region", "mmio-sram";
  reg = <0x2003FFC0 64>;
  zephyr,memory-region = "RetainedMem";
  status = "okay";

  retainedmem {
    compatible = "zephyr,retained-ram";
    status = "okay";
    #address-cells = <1>;
    #size-cells = <1>;

    retention0: retention@0 {
      compatible = "zephyr,retention";
      status = "okay";
      reg = <0x0 0x40>;
      prefix = [04 fa];
      checksum = <1>;
    };
  };
};

Properties

Node specific properties

Properties not inherited from the base binding file.

Name

Type

Details

prefix

uint8-array

An optional magic prefix, which indicates that the data has been set
(applies to the header of the data, reduces the available user data
size).

checksum

int

An optional data verification checksum, which indicates that the data is
valid (appended to the footer of the data, reduces the available user
data size). Value is size in bytes (0 for none, 1 for 8-bit CRC, 2 for
16-bit CRC, 4 for 32-bit CRC). Default is to not use a checksum.

Deprecated node specific properties

Deprecated properties not inherited from the base binding file.

(None)

Base properties

Properties inherited from the base binding file, which defines common properties that may be set on many nodes. Not all of these may apply to the “zephyr,retention” compatible.

Name

Type

Details

#address-cells

int

Address reg cell is for the offset of the area in parent node, can be
increased if multiple retention partitions are used or parts are
reserved.

Constant value: 1

#size-cells

int

Size reg cell is for the size of the area, which includes sizes of
prefix and checksum (if enabled).

Constant value: 1

reg

array

register space

This property is required.

See Important properties for more information.

status

string

indicates the operational status of a device

Legal values: 'ok', 'okay', 'disabled', 'reserved', 'fail', 'fail-sss'

See Important properties for more information.

compatible

string-array

compatible strings

This property is required.

See Important properties for more information.

reg-names

string-array

name of each register space

interrupts

array

interrupts for device

See Important properties for more information.

interrupts-extended

compound

extended interrupt specifier for device

interrupt-names

string-array

name of each interrupt

interrupt-parent

phandle

phandle to interrupt controller node

label

string

Human readable string describing the device (used as device_get_binding() argument)

See Important properties for more information.

This property is deprecated.

clocks

phandle-array

Clock gate information

clock-names

string-array

name of each clock

dmas

phandle-array

DMA channels specifiers

dma-names

string-array

Provided names of DMA channel specifiers

io-channels

phandle-array

IO channels specifiers

io-channel-names

string-array

Provided names of IO channel specifiers

mboxes

phandle-array

mailbox / IPM channels specifiers

mbox-names

string-array

Provided names of mailbox / IPM channel specifiers

power-domains

phandle-array

Power domain specifiers

power-domain-names

string-array

Provided names of power domain specifiers

#power-domain-cells

int

Number of cells in power-domains property

zephyr,deferred-init

boolean

Do not initialize device automatically on boot. Device should be manually
initialized using device_init().

wakeup-source

boolean

Property to identify that a device can be used as wake up source.

When this property is provided a specific flag is set into the
device that tells the system that the device is capable of
wake up the system.

Wake up capable devices are disabled (interruptions will not wake up
the system) by default but they can be enabled at runtime if necessary.

zephyr,pm-device-runtime-auto

boolean

Automatically configure the device for runtime power management after the
init function runs.

zephyr,disabling-power-states

phandles

List of power states that will disable this device power.