[PATCH v2 15/18] dt-bindings: riscv: Describe physical memory regions

[Rob Herring (Arm)]

On Wed, 08 Oct 2025 18:57:51 -0700, Samuel Holland wrote:
> Information about physical memory regions is needed by both the kernel
> and M-mode firmware. For example, the kernel needs to know about
> noncacheable aliases of cacheable memory in order to allocate coherent
> memory pages for DMA. M-mode firmware needs to know about those aliases
> so it can protect itself from lower-privileged software.
> 
> The RISC-V Privileged Architecture delegates the description of Physical
> Memory Attributes (PMAs) to the platform. On DT-based platforms, it
> makes sense to put this information in the devicetree.
> 
> Signed-off-by: Samuel Holland <samuel.holland at sifive.com>
> ---
> 
> Changes in v2:
>  - Remove references to Physical Address Width (no longer part of Smmpt)
>  - Remove special first entry from the list of physical memory regions
>  - Fix compatible string in example
> 
>  .../bindings/riscv/physical-memory.yaml       | 91 +++++++++++++++++++
>  include/dt-bindings/riscv/physical-memory.h   | 44 +++++++++
>  2 files changed, 135 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/riscv/physical-memory.yaml
>  create mode 100644 include/dt-bindings/riscv/physical-memory.h
> 

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

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/riscv/physical-memory.example.dtb: / (beagle,beaglev-starlight-jh7100-r0): 'model' is a required property
	from schema $id: http://devicetree.org/schemas/root-node.yaml#

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20251009015839.3460231-16-samuel.holland@sifive.com

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.