From: Rafał Miłecki rafal@milecki.pl
U-Boot env data is a way of storing firmware variables. It's a format that can be used of top of various storage devices. Its binding should be an NVMEM layout instead of a standalone device.
This patch adds layout binding which allows using it on top of MTD NVMEM device as well as any other. At the same time it deprecates the old combined binding.
Signed-off-by: Rafał Miłecki rafal@milecki.pl --- V2: Add "-layout" suffix to compatibles to avoid conflict
.../nvmem/layouts/u-boot,env-layout.yaml | 55 +++++++++++++++++++ .../devicetree/bindings/nvmem/u-boot,env.yaml | 6 ++ 2 files changed, 61 insertions(+) create mode 100644 Documentation/devicetree/bindings/nvmem/layouts/u-boot,env-layout.yaml
diff --git a/Documentation/devicetree/bindings/nvmem/layouts/u-boot,env-layout.yaml b/Documentation/devicetree/bindings/nvmem/layouts/u-boot,env-layout.yaml new file mode 100644 index 000000000000..3b4d8f2a44e1 --- /dev/null +++ b/Documentation/devicetree/bindings/nvmem/layouts/u-boot,env-layout.yaml @@ -0,0 +1,55 @@ +# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/nvmem/layouts/u-boot,env-layout.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: NVMEM layout of U-Boot environment variables + +maintainers: + - Rafał Miłecki rafal@milecki.pl + +description: + U-Boot uses environment variables to store device parameters and + configuration. They may be used for booting process, setup or keeping end user + info. + + Data is stored using U-Boot specific formats (variant specific header and NUL + separated key-value pairs). + +properties: + compatible: + oneOf: + - description: A standalone env data block + const: u-boot,env-layout + - description: Two redundant blocks with active one flagged + const: u-boot,env-redundant-bool-layout + - description: Two redundant blocks with active having higher counter + const: u-boot,env-redundant-count-layout + - description: Broadcom's variant with custom header + const: brcm,env-layout + +additionalProperties: false + +examples: + - | + partitions { + compatible = "fixed-partitions"; + #address-cells = <1>; + #size-cells = <1>; + + partition@0 { + reg = <0x0 0x40000>; + label = "u-boot"; + read-only; + }; + + partition@40000 { + reg = <0x40000 0x10000>; + label = "u-boot-env"; + + nvmem-layout { + compatible = "u-boot,env-layout"; + }; + }; + }; diff --git a/Documentation/devicetree/bindings/nvmem/u-boot,env.yaml b/Documentation/devicetree/bindings/nvmem/u-boot,env.yaml index 9c36afc7084b..6c2a3ca5f051 100644 --- a/Documentation/devicetree/bindings/nvmem/u-boot,env.yaml +++ b/Documentation/devicetree/bindings/nvmem/u-boot,env.yaml @@ -26,9 +26,15 @@ description: |
Variables can be defined as NVMEM device subnodes.
+ Introduction of NVMEM layouts exposed a limitation of this binding design. + Description of NVMEM data content should be separated from NVMEM devices. + Since the introduction of U-Boot env data layout this binding is deprecated. + maintainers: - Rafał Miłecki rafal@milecki.pl
+deprecated: true + properties: compatible: oneOf: