xref: /kernel/linux/linux-6.6/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.yaml

# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
%YAML 1.2
---
$id: http://devicetree.org/schemas/mtd/partitions/brcm,bcm947xx-cfe-partitions.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Broadcom BCM47xx Partitions

description: |
  Broadcom is one of hardware manufacturers providing SoCs (BCM47xx) used in
  home routers. Their BCM947xx boards using CFE bootloader have several
  partitions without any on-flash partition table. On some devices their sizes
  and/or meanings can also vary so fixed partitioning can't be used.

  Discovering partitions on these devices is possible thanks to having a special
  header and/or magic signature at the beginning of each of them. They are also
  block aligned which is important for determinig a size.

  Most of partitions use ASCII text based magic for determining a type. More
  complex partitions (like TRX with its HDR0 magic) may include extra header
  containing some details, including a length.

  A list of supported partitions includes:
  1) Bootloader with Broadcom's CFE (Common Firmware Environment)
  2) NVRAM with configuration/calibration data
  3) Device manufacturer's data with some default values (e.g. SSIDs)
  4) TRX firmware container which can hold up to 4 subpartitions
  5) Backup TRX firmware used after failed upgrade

  As mentioned earlier, role of some partitions may depend on extra
  configuration. For example both: main firmware and backup firmware use the
  same TRX format with the same header. To distinguish currently used firmware a
  CFE's environment variable "bootpartition" is used.

maintainers:
  - Rafał Miłecki <rafal@milecki.pl>

select: false

properties:
  compatible:
    const: brcm,bcm947xx-cfe-partitions

additionalProperties: false

examples:
  - |
    partitions {
        compatible = "brcm,bcm947xx-cfe-partitions";
    };