[PATCH v2] dt-bindings: mtd: Add a schema for binman

[Simon Glass <sjg@chromium.org>]

Binman[1] is a tool for creating firmware images. It allows you to
combine various binaries and place them in an output file.

Binman uses a DT schema to describe an image, in enough detail that
it can be automatically built from component parts, disassembled,
replaced, listed, etc.

Images are typically stored in flash, which is why this binding is
targeted at mtd. Previous discussion is at [2] [3].

This is only a starting point, an attempt to align on the best way to
add this to the schema.

[1] https://u-boot.readthedocs.io/en/stable/develop/package/binman.html
[2] https://lore.kernel.org/u-boot/20230821180220.2724080-3-sjg@chromium.org/
[3] https://www.spinics.net/lists/devicetree/msg626149.html

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

Changes in v2:
- Use "binman" for compatible instead of "u-boot,binman"
- Significantly rework the patch
- Use make dt_binding_check DT_SCHEMA_FILES=Documentation/../partitions

 .../bindings/mtd/partitions/binman.yaml       | 59 ++++++++++++++++++
 .../mtd/partitions/binman/atf-bl31.yaml       | 43 +++++++++++++
 .../bindings/mtd/partitions/binman/entry.yaml | 62 +++++++++++++++++++
 .../mtd/partitions/binman/u-boot.yaml         | 43 +++++++++++++
 .../bindings/mtd/partitions/partitions.yaml   |  1 +
 MAINTAINERS                                   |  5 ++
 6 files changed, 213 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/partitions/binman.yaml
 create mode 100644 Documentation/devicetree/bindings/mtd/partitions/binman/atf-bl31.yaml
 create mode 100644 Documentation/devicetree/bindings/mtd/partitions/binman/entry.yaml
 create mode 100644 Documentation/devicetree/bindings/mtd/partitions/binman/u-boot.yaml

diff --git a/Documentation/devicetree/bindings/mtd/partitions/binman.yaml b/Documentation/devicetree/bindings/mtd/partitions/binman.yaml
new file mode 100644
index 000000000000..31accab37055
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/partitions/binman.yaml
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2023 Google LLC
+
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/partitions/binman.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Binman firmware layout
+
+maintainers:
+  - Simon Glass <sjg@chromium.org>
+
+select: false
+
+description: |
+  The binman 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.
+
+  Documentation for Binman is available at:
+
+  https://u-boot.readthedocs.io/en/latest/develop/package/binman.html
+
+  with the current image-description format at:
+
+  https://u-boot.readthedocs.io/en/latest/develop/package/binman.html#image-description-format
+
+properties:
+  reg:
+    description: partition's offset and size within the flash
+    maxItems: 1
+
+  compatible:
+    const: binman
+
+  "#address-cells":
+    enum: [ 1, 2 ]
+
+  "#size-cells":
+    enum: [ 1, 2 ]
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    binman {
+        compatible = "binman";
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        partition@100000 {
+            compatible = "brcm,bcm4908-firmware";
+            reg = <0x100000 0xf00000>;
+        };
+    };
diff --git a/Documentation/devicetree/bindings/mtd/partitions/binman/atf-bl31.yaml b/Documentation/devicetree/bindings/mtd/partitions/binman/atf-bl31.yaml
new file mode 100644
index 000000000000..7d28e7e1d01d
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/partitions/binman/atf-bl31.yaml
@@ -0,0 +1,43 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2023 Google LLC
+
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/partitions/binman/atf-bl31.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ARM Trusted Firmware BL31
+
+maintainers:
+  - Simon Glass <sjg@chromium.org>
+
+description:
+  Holds a BL31 binary file from the ARM Trusted Firmware project.
+
+allOf:
+  - $ref: entry.yaml#
+
+properties:
+  compatible:
+    const: binman,atf-bl31
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    binman {
+        compatible = "binman";
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        partition@0 {
+            reg = <0x0 0xa0000>;
+            compatible = "binman,entry";
+        };
+
+        partition@100000 {
+            reg = <0x100000 0x200000>;
+            compatible = "binman,atf-bl31";
+            compression = "lz4";
+        };
+    };
diff --git a/Documentation/devicetree/bindings/mtd/partitions/binman/entry.yaml b/Documentation/devicetree/bindings/mtd/partitions/binman/entry.yaml
new file mode 100644
index 000000000000..9991c83aa0cf
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/partitions/binman/entry.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2023 Google LLC
+
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/partitions/binman/entry.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Binman entry
+
+maintainers:
+  - Simon Glass <sjg@chromium.org>
+
+description: |
+  This node specifies a single, generic entry in the firmware.
+
+  Entries have a specific type, indicated by the compatible string.
+
+properties:
+  reg:
+    description: partition's offset and size within the flash
+    maxItems: 1
+
+  compression:
+    $ref: /schemas/types.yaml#/definitions/string
+    description:
+      Compression algorithm to use, chosen from a list of well-known algorithms.
+      The contents are compressed using this algorithm.
+
+    enum:
+      - none
+      - bzip2
+      - gzip
+      - lzop
+      - lz4
+      - lzma
+      - xz
+      - zstd
+
+required:
+  - compatible
+
+additionalProperties: true
+
+examples:
+  - |
+    binman {
+        compatible = "binman";
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        partition@0 {
+            reg = <0x0 0xa0000>;
+            compatible = "binman,entry";
+        };
+
+        partition@100000 {
+            reg = <0x100000 0x200000>;
+            compatible = "binman,entry";
+            compression = "lz4";
+        };
+    };
diff --git a/Documentation/devicetree/bindings/mtd/partitions/binman/u-boot.yaml b/Documentation/devicetree/bindings/mtd/partitions/binman/u-boot.yaml
new file mode 100644
index 000000000000..e5f3583f746c
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/partitions/binman/u-boot.yaml
@@ -0,0 +1,43 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2023 Google LLC
+
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mtd/partitions/binman/u-boot.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: U-Boot
+
+maintainers:
+  - Simon Glass <sjg@chromium.org>
+
+description:
+  Holds a binary file (u-boot.bin) from the U-Boot project.
+
+allOf:
+  - $ref: entry.yaml#
+
+properties:
+  compatible:
+    const: binman,u-boot
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    binman {
+        compatible = "binman";
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        partition@0 {
+            reg = <0x0 0xa0000>;
+            compatible = "binman,u-boot";
+        };
+
+        partition@100000 {
+            reg = <0x100000 0x200000>;
+            compatible = "binman,atf-bl31";
+            compression = "lz4";
+        };
+    };
diff --git a/Documentation/devicetree/bindings/mtd/partitions/partitions.yaml b/Documentation/devicetree/bindings/mtd/partitions/partitions.yaml
index 1dda2c80747b..849fd15d085c 100644
--- a/Documentation/devicetree/bindings/mtd/partitions/partitions.yaml
+++ b/Documentation/devicetree/bindings/mtd/partitions/partitions.yaml
@@ -15,6 +15,7 @@ maintainers:
 
 oneOf:
   - $ref: arm,arm-firmware-suite.yaml
+  - $ref: binman.yaml
   - $ref: brcm,bcm4908-partitions.yaml
   - $ref: brcm,bcm947xx-cfe-partitions.yaml
   - $ref: fixed-partitions.yaml
diff --git a/MAINTAINERS b/MAINTAINERS
index a4c30221eb30..ebcbfb4292e8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3505,6 +3505,11 @@ F:	Documentation/filesystems/bfs.rst
 F:	fs/bfs/
 F:	include/uapi/linux/bfs_fs.h
 
+BINMAN
+M:	Simon Glass <sjg@chromium.org>
+S:	Supported
+F:	Documentation/devicetree/bindings/mtd/partitions/binman*
+
 BITMAP API
 M:	Yury Norov <yury.norov@gmail.com>
 R:	Andy Shevchenko <andriy.shevchenko@linux.intel.com>
-- 
2.42.0.515.g380fc7ccd1-goog