Re: [PATCH RFC linux] dt-bindings: nvmem: Add binding for U-Boot environment NVMEM provider

On 14/10/2021 00:20, Marek Behún wrote:

Add device tree bindings for U-Boot environment NVMEM provider.

U-Boot environment can be stored at a specific offset of a MTD device, EEPROM, MMC, NAND or SATA device, on an UBI volume, or in a file on a filesystem.

The environment can contain information such as device's MAC address, which should be used by the ethernet controller node.

Have you looked at ./Documentation/devicetree/bindings/mtd/partitions/nvmem-cells.yaml ?

--srini

Signed-off-by: Marek Behún kabel@kernel.org

.../bindings/nvmem/denx,u-boot-env.yaml | 88 +++++++++++++++++++ include/dt-bindings/nvmem/u-boot-env.h | 18 ++++ 2 files changed, 106 insertions(+) create mode 100644 Documentation/devicetree/bindings/nvmem/denx,u-boot-env.yaml create mode 100644 include/dt-bindings/nvmem/u-boot-env.h

diff --git a/Documentation/devicetree/bindings/nvmem/denx,u-boot-env.yaml b/Documentation/devicetree/bindings/nvmem/denx,u-boot-env.yaml new file mode 100644 index 000000000000..56505c08e622 --- /dev/null +++ b/Documentation/devicetree/bindings/nvmem/denx,u-boot-env.yaml @@ -0,0 +1,88 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/nvmem/denx,u-boot-env.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml#

+title: U-Boot environment NVMEM Device Tree Bindings

+maintainers:

• • Marek Behún kabel@kernel.org

+description:

• This binding represents U-Boot's environment NVMEM settings which can be
• stored on a specific offset of an EEPROM, MMC, NAND or SATA device, or
• an UBI volume, or in a file on a filesystem.

+properties:

• compatible:
• const: denx,u-boot-env
• path:
• description:

•  The path to the file containing the environment if on a filesystem.
  

• $ref: /schemas/types.yaml#/definitions/string

+patternProperties:

• "^[^=]+$":
• type: object
• description:

•  This node represents one U-Boot environment variable, which is also one
  

•  NVMEM data cell.
  

• properties:

•  name:
  

•    description:
  

•      If the variable name contains characters not allowed in device tree node
  

•      name, use this property to specify the name, otherwise the variable name
  

•      is equal to node name.
  

•    $ref: /schemas/types.yaml#/definitions/string
  

•  type:
  

•    description:
  

•      Type of the variable. Since variables, even integers and MAC addresses,
  

•      are stored as strings in U-Boot environment, for proper conversion the
  

•      type needs to be specified. Use one of the U_BOOT_ENV_TYPE_* prefixed
  

•      definitions from include/dt-bindings/nvmem/u-boot-env.h.
  

•    $ref: /schemas/types.yaml#/definitions/uint32
  

•    minimum: 0
  

•    maximum: 5
  

• required:

•  - type
  

+required:

• • compatible

+additionalProperties: true

+examples:

• • |
• #include <dt-bindings/nvmem/u-boot-env.h>
• spi-flash {

•    partitions {
  

•        compatible = "fixed-partitions";
  

•        #address-cells = <1>;
  

•        #size-cells = <1>;
  

•        partition@180000 {
  

•            compatible = "denx,u-boot-env";
  

•            label = "u-boot-env";
  

•            reg = <0x180000 0x10000>;
  

•            eth0_addr: ethaddr {
  

•                type = <U_BOOT_ENV_TYPE_MAC_ADDRESS>;
  

•            };
  

•        };
  

•    };
  

• };
• ethernet-controller {

•    nvmem-cells = <&eth0_addr>;
  

•    nvmem-cell-names = "mac-address";
  

• };

+... diff --git a/include/dt-bindings/nvmem/u-boot-env.h b/include/dt-bindings/nvmem/u-boot-env.h new file mode 100644 index 000000000000..760e5b240619 --- /dev/null +++ b/include/dt-bindings/nvmem/u-boot-env.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/*

• • Macros for U-Boot environment NVMEM device tree bindings.
• • Copyright (C) 2021 Marek Behún kabel@kernel.org
• */

+#ifndef __DT_BINDINGS_NVMEM_U_BOOT_ENV_H +#define __DT_BINDINGS_NVMEM_U_BOOT_ENV_H

+#define U_BOOT_ENV_TYPE_STRING 0 +#define U_BOOT_ENV_TYPE_ULONG 1 +#define U_BOOT_ENV_TYPE_BOOL 2 +#define U_BOOT_ENV_TYPE_MAC_ADDRESS 3 +#define U_BOOT_ENV_TYPE_ULONG_HEX 4 +#define U_BOOT_ENV_TYPE_ULONG_DEC 5

+#endif /* __DT_BINDINGS_NVMEM_U_BOOT_ENV_H */