Re: [PATCH v7] dt-bindings: reserved-memory: Document iommu-addresses

[Rob Herring <robh@kernel.org>]

On Tue, 05 Jul 2022 15:06:52 +0200, Thierry Reding wrote:
> From: Thierry Reding <treding@nvidia.com>
> 
> This adds the "iommu-addresses" property to reserved-memory nodes, which
> allow describing the interaction of memory regions with IOMMUs. Two use-
> cases are supported:
> 
>   1. Static mappings can be described by pairing the "iommu-addresses"
>      property with a "reg" property. This is mostly useful for adopting
>      firmware-allocated buffers via identity mappings. One common use-
>      case where this is required is if early firmware or bootloaders
>      have set up a bootsplash framebuffer that a display controller is
>      actively scanning out from during the operating system boot
>      process.
> 
>   2. If an "iommu-addresses" property exists without a "reg" property,
>      the reserved-memory node describes an IOVA reservation. Such memory
>      regions are excluded from the IOVA space available to operating
>      system drivers and can be used for regions that must not be used to
>      map arbitrary buffers.
> 
> Each mapping or reservation is tied to a specific device via a phandle
> to the device's device tree node. This allows a reserved-memory region
> to be reused across multiple devices.
> 
> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
> Changes in v7:
> - keep reserved-memory.txt to avoid broken references
> 
> Changes in v6:
> - add device phandle to iommu-addresses property in examples
> - remove now unused dt-bindings/reserved-memory.h header
> ---
>  .../reserved-memory/reserved-memory.yaml      | 62 +++++++++++++++++++
>  1 file changed, 62 insertions(+)
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:22.7-45: Warning (reg_format): /reserved-memory/framebuffer@90000000:reg: property has invalid length (16 bytes) (#address-cells == 2, #size-cells == 1)
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:29.7-40: Warning (reg_format): /bus@0/adsp@2990000:reg: property has invalid length (16 bytes) (#address-cells == 2, #size-cells == 1)
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:34.7-42: Warning (reg_format): /bus@0/display@15200000:reg: property has invalid length (16 bytes) (#address-cells == 2, #size-cells == 1)
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:9.5-12: Warning (ranges_format): /reserved-memory:ranges: empty "ranges" property but its #size-cells (1) differs from / (2)
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:27.9-37.5: Warning (unit_address_vs_reg): /bus@0: node has a unit name, but no reg or ranges property
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: Warning (pci_device_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: Warning (pci_device_bus_num): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: Warning (simple_bus_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: Warning (i2c_bus_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: Warning (spi_bus_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:21.30-24.7: Warning (avoid_default_addr_size): /reserved-memory/framebuffer@90000000: Relying on default #address-cells value
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:21.30-24.7: Warning (avoid_default_addr_size): /reserved-memory/framebuffer@90000000: Relying on default #size-cells value
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:28.24-31.7: Warning (avoid_default_addr_size): /bus@0/adsp@2990000: Relying on default #address-cells value
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:28.24-31.7: Warning (avoid_default_addr_size): /bus@0/adsp@2990000: Relying on default #size-cells value
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:33.27-36.7: Warning (avoid_default_addr_size): /bus@0/display@15200000: Relying on default #address-cells value
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dts:33.27-36.7: Warning (avoid_default_addr_size): /bus@0/display@15200000: Relying on default #size-cells value
Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: Warning (unique_unit_address_if_enabled): Failed prerequisite 'avoid_default_addr_size'
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: /: bus@0: 'anyOf' conditional failed, one must be fixed:
	'reg' is a required property
	'ranges' is a required property
	From schema: /usr/local/lib/python3.10/dist-packages/dtschema/schemas/root-node.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: /: 'compatible' is a required property
	From schema: /usr/local/lib/python3.10/dist-packages/dtschema/schemas/root-node.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/reserved-memory/reserved-memory.example.dtb: /: 'model' is a required property
	From schema: /usr/local/lib/python3.10/dist-packages/dtschema/schemas/root-node.yaml

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/patch/

This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.

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.