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[PATCH 3/5] dt-bindings: Add Bao I/O dispatcher driver binding

joaopeixoto@osyx.tech posted 5 patches 1 month, 2 weeks ago
There is a newer version of this series
[PATCH 3/5] dt-bindings: Add Bao I/O dispatcher driver binding
Posted by joaopeixoto@osyx.tech 1 month, 2 weeks ago 
From: João Peixoto <joaopeixoto@osyx.tech>

This patch adds a Device Tree binding for the Bao I/O Dispatcher kernel
module, which can be loaded into backend VMs. The I/O Dispatcher
provides the bridge between the Bao hypervisor Remote I/O system and the
frontend device model in userspace, offering a unified API to support
various VirtIO backends.

The dispatcher handles hypercalls to the Bao hypervisor, IRQ/eventfd
forwarding, and provides a character device interface for frontend
devices, enabling efficient communication between the hypervisor and
userspace device models.

The binding documents the following properties:
  - compatible: "bao,io-dispatcher"
  - reg: Memory regions for the dispatcher (multiple VirtIO devices)
  - interrupts: Interrupts used by the devices
  - interrupt-parent: Parent interrupt controller

This enables kernel drivers to correctly instantiate and configure Bao
I/O Dispatcher modules based on the DT description.

Signed-off-by: João Peixoto <joaopeixoto@osyx.tech>
---
 .../bindings/bao/io-dispatcher.yaml           | 67 +++++++++++++++++++
 1 file changed, 67 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/bao/io-dispatcher.yaml

diff --git a/Documentation/devicetree/bindings/bao/io-dispatcher.yaml b/Documentation/devicetree/bindings/bao/io-dispatcher.yaml
new file mode 100644
index 000000000000..7795f55d3ff9
--- /dev/null
+++ b/Documentation/devicetree/bindings/bao/io-dispatcher.yaml
@@ -0,0 +1,67 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/bao/io-dispatcher.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Bao I/O Dispatcher Device
+
+maintainers:
+  - João Peixoto <joaopeixoto@osyx.tech>
+  - José Martins <jose@osyx.tech>
+  - David Cerdeira <davidmcerdeira@osyx.tech>
+
+description: |
+  I/O Dispatcher device for Bao hypervisor guests. Handles multiple VirtIO
+  backend devices and their interrupts.
+
+properties:
+  compatible:
+    const: "bao,io-dispatcher"
+    description: Device compatible string.
+
+  reg:
+    description: |
+      Memory regions for each VirtIO backend device.
+    maxItems: 20
+    type: array
+    items:
+      type: integer
+
+  interrupts:
+    description: |
+      Interrupt numbers for each VirtIO backend device.
+    type: array
+    items:
+      type: integer
+    minItems: 3
+    maxItems: 3
+
+  interrupt-parent:
+    description: Parent interrupt controller node
+    type: string
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - interrupt-parent
+
+additionalProperties: false
+
+examples:
+  - |
+    bao_io_dispatcher: bao-io-dispatcher {
+        compatible = "bao,io-dispatcher";
+        reg = <0x0 0x50000000 0x0 0x01000000
+               0x0 0x51000000 0x0 0x01000000
+               0x0 0x52000000 0x0 0x01000000
+               0x0 0x53000000 0x0 0x01000000
+               0x0 0x54000000 0x0 0x01000000>;
+        interrupts = <0x0 0x08 0x1
+                      0x0 0x09 0x1
+                      0x0 0x0a 0x1
+                      0x0 0x0b 0x1
+                      0x0 0x0c 0x1>;
+        interrupt-parent = <&gic>;
+    };
-- 
2.43.0
Re: [PATCH 3/5] dt-bindings: Add Bao I/O dispatcher driver binding
Posted by Krzysztof Kozlowski 1 month, 2 weeks ago 
On Wed, Dec 24, 2025 at 01:52:15PM +0000, joaopeixoto@osyx.tech wrote:
> From: João Peixoto <joaopeixoto@osyx.tech>
> 
> This patch adds a Device Tree binding for the Bao I/O Dispatcher kernel
> module, which can be loaded into backend VMs. The I/O Dispatcher
> provides the bridge between the Bao hypervisor Remote I/O system and the
> frontend device model in userspace, offering a unified API to support
> various VirtIO backends.
> 
> The dispatcher handles hypercalls to the Bao hypervisor, IRQ/eventfd
> forwarding, and provides a character device interface for frontend
> devices, enabling efficient communication between the hypervisor and
> userspace device models.
> 
> The binding documents the following properties:
>   - compatible: "bao,io-dispatcher"
>   - reg: Memory regions for the dispatcher (multiple VirtIO devices)
>   - interrupts: Interrupts used by the devices
>   - interrupt-parent: Parent interrupt controller
> 
> This enables kernel drivers to correctly instantiate and configure Bao
> I/O Dispatcher modules based on the DT description.
> 
> Signed-off-by: João Peixoto <joaopeixoto@osyx.tech>
> ---
>  .../bindings/bao/io-dispatcher.yaml           | 67 +++++++++++++++++++
>  1 file changed, 67 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/bao/io-dispatcher.yaml
> 
> diff --git a/Documentation/devicetree/bindings/bao/io-dispatcher.yaml b/Documentation/devicetree/bindings/bao/io-dispatcher.yaml
> new file mode 100644
> index 000000000000..7795f55d3ff9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/bao/io-dispatcher.yaml
> @@ -0,0 +1,67 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/bao/io-dispatcher.yaml#"

You did not even bother to test it.

> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: Bao I/O Dispatcher Device
> +
> +maintainers:
> +  - João Peixoto <joaopeixoto@osyx.tech>
> +  - José Martins <jose@osyx.tech>
> +  - David Cerdeira <davidmcerdeira@osyx.tech>
> +
> +description: |
> +  I/O Dispatcher device for Bao hypervisor guests. Handles multiple VirtIO
> +  backend devices and their interrupts.
> +
> +properties:
> +  compatible:
> +    const: "bao,io-dispatcher"
> +    description: Device compatible string.
> +
> +  reg:
> +    description: |
> +      Memory regions for each VirtIO backend device.
> +    maxItems: 20
> +    type: array
> +    items:
> +      type: integer

Don't send us LLM junk. You cannot come with such syntax, it does
not exist. Sending such LLM output is disregard to our time.

NAK


Best regards,
Krzysztof
Re: [PATCH 3/5] dt-bindings: Add Bao I/O dispatcher driver binding
Posted by Rob Herring (Arm) 1 month, 2 weeks ago 
On Wed, 24 Dec 2025 13:52:15 +0000, joaopeixoto@osyx.tech wrote:
> From: João Peixoto <joaopeixoto@osyx.tech>
> 
> This patch adds a Device Tree binding for the Bao I/O Dispatcher kernel
> module, which can be loaded into backend VMs. The I/O Dispatcher
> provides the bridge between the Bao hypervisor Remote I/O system and the
> frontend device model in userspace, offering a unified API to support
> various VirtIO backends.
> 
> The dispatcher handles hypercalls to the Bao hypervisor, IRQ/eventfd
> forwarding, and provides a character device interface for frontend
> devices, enabling efficient communication between the hypervisor and
> userspace device models.
> 
> The binding documents the following properties:
>   - compatible: "bao,io-dispatcher"
>   - reg: Memory regions for the dispatcher (multiple VirtIO devices)
>   - interrupts: Interrupts used by the devices
>   - interrupt-parent: Parent interrupt controller
> 
> This enables kernel drivers to correctly instantiate and configure Bao
> I/O Dispatcher modules based on the DT description.
> 
> Signed-off-by: João Peixoto <joaopeixoto@osyx.tech>
> ---
>  .../bindings/bao/io-dispatcher.yaml           | 67 +++++++++++++++++++
>  1 file changed, 67 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/bao/io-dispatcher.yaml
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:
./Documentation/devicetree/bindings/bao/ipcshmem.yaml:4:6: [error] string value is redundantly quoted with any quotes (quoted-strings)
./Documentation/devicetree/bindings/bao/ipcshmem.yaml:5:10: [error] string value is redundantly quoted with any quotes (quoted-strings)
./Documentation/devicetree/bindings/bao/ipcshmem.yaml:17:1: [error] syntax error: found character '\t' that cannot start any token (syntax)
./Documentation/devicetree/bindings/bao/io-dispatcher.yaml:4:6: [error] string value is redundantly quoted with any quotes (quoted-strings)
./Documentation/devicetree/bindings/bao/io-dispatcher.yaml:5:10: [error] string value is redundantly quoted with any quotes (quoted-strings)
./Documentation/devicetree/bindings/bao/io-dispatcher.yaml:20:12: [error] string value is redundantly quoted with any quotes (quoted-strings)

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/ipcshmem.yaml: ignoring, error parsing file
./Documentation/devicetree/bindings/bao/ipcshmem.yaml:17:1: found a tab character where an indentation space is expected
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/io-dispatcher.yaml: properties:reg: 'anyOf' conditional failed, one must be fixed:
	'type' is not one of ['maxItems', 'description', 'deprecated']
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	'items' is not one of ['maxItems', 'description', 'deprecated']
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	Additional properties are not allowed ('type' was unexpected)
		hint: Arrays must be described with a combination of minItems/maxItems/items
	'maxItems' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	'type' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	'items' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/io-dispatcher.yaml: properties:reg:items: 'anyOf' conditional failed, one must be fixed:
		'maxItems' is a required property
			hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
		'type' is not one of ['maxItems', 'description', 'deprecated']
			hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
		Additional properties are not allowed ('type' was unexpected)
			hint: Arrays must be described with a combination of minItems/maxItems/items
		'type' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
			hint: "items" can be a list defining each entry or a schema applying to all items. A list has an implicit size. A schema requires minItems/maxItems to define the size.
		hint: cell array properties must define how many entries and what the entries are when there is more than one entry.
		from schema $id: http://devicetree.org/meta-schemas/cell.yaml
	1 was expected
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	hint: cell array properties must define how many entries and what the entries are when there is more than one entry.
	from schema $id: http://devicetree.org/meta-schemas/cell.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/io-dispatcher.yaml: properties:reg:type: 'array' is not one of ['boolean', 'object']
	from schema $id: http://devicetree.org/meta-schemas/core.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/io-dispatcher.yaml: properties:interrupts:type: 'array' is not one of ['boolean', 'object']
	from schema $id: http://devicetree.org/meta-schemas/core.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/io-dispatcher.yaml: properties:interrupt-parent:type: 'string' is not one of ['boolean', 'object']
	from schema $id: http://devicetree.org/meta-schemas/core.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/io-dispatcher.yaml: properties:interrupts: 'anyOf' conditional failed, one must be fixed:
	'type' is not one of ['maxItems', 'description', 'deprecated']
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	'items' is not one of ['maxItems', 'description', 'deprecated']
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	'minItems' is not one of ['maxItems', 'description', 'deprecated']
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	Additional properties are not allowed ('type' was unexpected)
		hint: Arrays must be described with a combination of minItems/maxItems/items
	'type' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	'items' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	'minItems' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	'maxItems' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
	/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/io-dispatcher.yaml: properties:interrupts:items: 'anyOf' conditional failed, one must be fixed:
		'maxItems' is a required property
			hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
		'type' is not one of ['maxItems', 'description', 'deprecated']
			hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
		Additional properties are not allowed ('type' was unexpected)
			hint: Arrays must be described with a combination of minItems/maxItems/items
		'type' is not one of ['description', 'deprecated', 'const', 'enum', 'minimum', 'maximum', 'multipleOf', 'default', '$ref', 'oneOf']
			hint: "items" can be a list defining each entry or a schema applying to all items. A list has an implicit size. A schema requires minItems/maxItems to define the size.
		hint: cell array properties must define how many entries and what the entries are when there is more than one entry.
		from schema $id: http://devicetree.org/meta-schemas/cell.yaml
	1 was expected
		hint: Only "maxItems" is required for a single entry if there are no constraints defined for the values.
	hint: cell array properties must define how many entries and what the entries are when there is more than one entry.
	from schema $id: http://devicetree.org/meta-schemas/cell.yaml
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/bao/io-dispatcher.yaml: properties: False schema does not allow {'description': 'Parent interrupt controller node', 'type': 'string'}
	from schema $id: http://devicetree.org/meta-schemas/interrupts.yaml
make[2]: *** Deleting file 'Documentation/devicetree/bindings/bao/ipcshmem.example.dts'
Documentation/devicetree/bindings/bao/ipcshmem.yaml:17:1: found a tab character where an indentation space is expected
make[2]: *** [Documentation/devicetree/bindings/Makefile:26: Documentation/devicetree/bindings/bao/ipcshmem.example.dts] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [/builds/robherring/dt-review-ci/linux/Makefile:1565: dt_binding_check] Error 2
make: *** [Makefile:248: __sub-make] Error 2

doc reference errors (make refcheckdocs):

See https://patchwork.kernel.org/project/devicetree/patch/20251224135217.25350-4-joaopeixoto@osyx.tech

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Patchew 2.1-devel-b67e4c2

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