Re: [PATCH v2 2/2] schemas: Add a schema for binman

On 2023-07-20 22:56 +03:00, Simon Glass wrote:

With this version I have done with a generic name, in this case 'data', as suggested by Alper Nebi Yasak. This may be controversial, but we may as well have the dicussion now. I assume that there are no other ongoing attempts to define the layout of firmware in devicetree.

Signed-off-by: Simon Glass sjg@chromium.org

Changes in v2:

• Reworked significantly based on Alper's comments

dtschema/schemas/firmware/binman/entry.yaml | 80 +++++++++++++++++++++ dtschema/schemas/firmware/image.yaml | 77 ++++++++++++++++++++ 2 files changed, 157 insertions(+) create mode 100644 dtschema/schemas/firmware/binman/entry.yaml create mode 100644 dtschema/schemas/firmware/image.yaml

diff --git a/dtschema/schemas/firmware/binman/entry.yaml b/dtschema/schemas/firmware/binman/entry.yaml new file mode 100644 index 0000000..d50f96d --- /dev/null +++ b/dtschema/schemas/firmware/binman/entry.yaml @@ -0,0 +1,80 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +# Copyright 2023 Google LLC

+%YAML 1.2 +--- +$id: http://devicetree.org/schemas/firmware/image/entry.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml#

+title: Image entry

+maintainers:

• • Simon Glass sjg@chromium.org

+description: |

• The entry node specifies a single entry in the firmware image.
• Entries have a specific type, such as "u-boot" or "atf-bl31". This is provided
• using compatible = "data,<type>".
• Note: This definition is intended to be hierarchical, so that entries can
• appear in other entries. Schema for that is TBD.

+properties:

• $nodename:
• pattern: "^[-a-z]+(-[0-9]+)?$"
• compatible:
• $ref: /schemas/types.yaml#/definitions/string
• offset:
• $ref: /schemas/types.yaml#/definitions/uint32
• description: |

•  Provides the offset of this entry from the start of its parent section.
  

•  This may be omitted in the description provided by Binman, in which case
  

•  the value is calculated as part of image packing.
  

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

•  Provides the size of this entry in bytes.
  

•  This may be omitted in the description provided by Binman, in which case
  

•  the value is calculated as part of image packing.
  

So AFAIU, binman will take none/one/both of "offset" and "size" as inputs and will pass them to the output unmodified, instead adding a "reg" pair of their calculated final values?

Is there a schema-computational way to ensure that "reg" has to contain the same values as "offset" and "size"? Or is that not a restriction at all and "reg" overrides the others?

• reg:
• description: |

•  Defines the offset and size of this entry, with reference to its parent
  

•  image / section.
  

•  Note This is typically omitted in the description provided to Binman,
  

•  since the value is calculated as part of image packing. Separate
  

•  properties are provided for the size and offset of an entry, so that it is
  

•  easy to specify none, one or both. The `reg` property is the only one that
  

•  needs to be looked at once the image has been built.
  

Do we not need a $ref for "reg"? Is there anything applicable?

BTW, I'm not that familiar with device-tree interpretation, I occasionally saw 'reg' being used as an <offset size> pair, and was mostly just asking if it's appropriate.

(Also TIL "ranges", and I'm imagining ranges = <0 $size 4G-$size 4G>; as an end-at-4gb replacement/generalization :P, but I know, later, later.)

+required:

• • compatible

+additionalProperties: false

+examples:

• • |
• firmware {

•  image {
  

•    compatible = "data,image";
  

•    #address-cells = <1>;
  

•    $size-cells = <1>;
  

•    u-boot@0 {
  

•      compatible = "data,u-boot";
  

•      reg = <0 0xa0000>;
  

•    };
  

•    atf-bl31@0x100000 {
  

•      compatible = "data,atf-bl31";
  

•      reg = <0x100000 0x20000>;
  

•    };
  

•  };
  

• };

diff --git a/dtschema/schemas/firmware/image.yaml b/dtschema/schemas/firmware/image.yaml new file mode 100644 index 0000000..949b067 --- /dev/null +++ b/dtschema/schemas/firmware/image.yaml @@ -0,0 +1,77 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +# Copyright 2023 Google LLC

+%YAML 1.2 +--- +$id: http://devicetree.org/schemas/firmware/image.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml#

+title: Binman firmware layout

+maintainers:

• • Simon Glass sjg@chromium.org

+description: |

• The image node provides a layout for firmware, used when packaging firmware
• from multiple projects. For now it just supports a very simple set of
• features, as a starting point for discussion.
• The Binman tool processes this node to produce a final image which can be
• loaded into suitable storage device. Documentation is at:
• https://u-boot.readthedocs.io/en/latest/develop/package/binman.html
• The current image-description format is here:
• https://u-boot.readthedocs.io/en/latest/develop/package/binman.html#image-de...
• It is desirable to reference the image from the storage-device node, perhaps
• using an image-desc property:
• spiflash@0 {

•  compatible = "spidev", "jedec,spi-nor";
  

•  image-desc = <&image>;
  

Bikeshedding, but maybe "layout" or "data,layout" would be nicer.

• };
• Note that the intention is to change Binman to use whatever schema is agreed
• here.

+properties:

• $nodename:
• const: binman

Doesn't match the example, and I guess you mean "^[-a-z]+(-[0-9]+)?$" like the entry one.

• compatible:
• const: data,image
• "#address-cells":
• const: 1
• "#size-cells":
• const: 1

+required:

• • compatible
• • "#address-cell"
• • "#size-cells"

+additionalProperties: false

+examples:

• • |
• firmware {

•  image {
  

•    compatible = "data,image";
  

•    #address-cells = <1>;
  

•    $size-cells = <1>;
  

•    u-boot@0 {
  

•      compatible = "data,u-boot";
  

•      reg = <0 0xa0000>;
  

•    };
  

•    atf-bl31@0x100000 {
  

•      compatible = "data,atf-bl31";
  

•      reg = <0x100000 0x20000>;
  

•    };
  

•  };
  

• };