From: Rafał Miłecki <ra...@milecki.pl> U-Boot environment variables can be stored in various data sources. MTD is just one of available options. Refactor DT binding into a layout so it can be used with UBI volumes and other NVMEM devices.
Link: https://lore.kernel.org/all/20231221173421.13737-1-zaj...@gmail.com/ Signed-off-by: Rafał Miłecki <ra...@milecki.pl> --- I'm sending this PATCH without Linux changes to see if this is the right approach - for developers and (DT) maintainers to review it first. My previous attempt (see above Link) turned out in refusal so I'm just trying to save some time in case this one goes wrong as well. Hopefully the included example (which I really think we should add) explains well how I think this binding should be used with layouts. If I get some positive feedback I'll work on V2 with actual Linux changes. .../bindings/nvmem/layouts/nvmem-layout.yaml | 1 + .../nvmem/{ => layouts}/u-boot,env.yaml | 39 ++++++++++++++++--- 2 files changed, 35 insertions(+), 5 deletions(-) rename Documentation/devicetree/bindings/nvmem/{ => layouts}/u-boot,env.yaml (75%) diff --git a/Documentation/devicetree/bindings/nvmem/layouts/nvmem-layout.yaml b/Documentation/devicetree/bindings/nvmem/layouts/nvmem-layout.yaml index 3b40f7880774..382507060651 100644 --- a/Documentation/devicetree/bindings/nvmem/layouts/nvmem-layout.yaml +++ b/Documentation/devicetree/bindings/nvmem/layouts/nvmem-layout.yaml @@ -21,6 +21,7 @@ oneOf: - $ref: fixed-layout.yaml - $ref: kontron,sl28-vpd.yaml - $ref: onie,tlv-layout.yaml + - $ref: u-boot,env.yaml properties: compatible: true diff --git a/Documentation/devicetree/bindings/nvmem/u-boot,env.yaml b/Documentation/devicetree/bindings/nvmem/layouts/u-boot,env.yaml similarity index 75% rename from Documentation/devicetree/bindings/nvmem/u-boot,env.yaml rename to Documentation/devicetree/bindings/nvmem/layouts/u-boot,env.yaml index 9c36afc7084b..56a8f55d4a09 100644 --- a/Documentation/devicetree/bindings/nvmem/u-boot,env.yaml +++ b/Documentation/devicetree/bindings/nvmem/layouts/u-boot,env.yaml @@ -1,10 +1,10 @@ # SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause %YAML 1.2 --- -$id: http://devicetree.org/schemas/nvmem/u-boot,env.yaml# +$id: http://devicetree.org/schemas/nvmem/layouts/u-boot,env.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# -title: U-Boot environment variables +title: U-Boot environment variables layout description: | U-Boot uses environment variables to store device parameters and @@ -21,9 +21,6 @@ description: | This binding allows marking storage device (as containing env data) and specifying used format. - Right now only flash partition case is covered but it may be extended to e.g. - UBI volumes in the future. - Variables can be defined as NVMEM device subnodes. maintainers: @@ -42,6 +39,7 @@ properties: const: brcm,env reg: + description: Partition offset and size for env on top of MTD maxItems: 1 bootcmd: @@ -58,6 +56,17 @@ properties: description: The first argument is a MAC address offset. const: 1 +allOf: + - if: + properties: + $nodename: + not: + contains: + pattern: "^partition@[0-9a-f]+$" + then: + properties: + reg: false + additionalProperties: false examples: @@ -101,3 +110,23 @@ examples: }; }; }; + - | + partition@0 { + reg = <0x0 0x100000>; + label = "ubi"; + compatible = "linux,ubi"; + + volumes { + ubi-volume-u-boot-env { + volname = "env"; + + nvmem-layout { + compatible = "u-boot,env"; + + ethaddr { + #nvmem-cell-cells = <1>; + }; + }; + }; + }; + }; -- 2.35.3
