Re: [PATCH 4/4 v5] dt-bindings: memory: Add jedec,lpddrX-channel binding

[Rob Herring <robh@kernel.org>]

On Fri, 30 Sep 2022 15:06:06 -0700, Julius Werner wrote:
> This patch adds a new device tree binding for an LPDDR channel to serve
> as a top-level organizing node for LPDDR part nodes nested below it. An
> LPDDR channel needs to have an "io-width" property to describe its width
> (this is important because this width does not always match the io-width
> of the part number, indicating that multiple parts are wired in parallel
> on the same channel), as well as one or more nested "rank@X" nodes.
> Those represent information about the individual ranks of each LPDDR
> part connected on that channel and should match the existing
> "jedec,lpddrX" bindings for individual LPDDR parts.
> 
> New platforms should be using this node -- the existing practice of
> providing a raw, toplevel "jedec,lpddrX" node without indication of how
> many identical parts are in the system should be considered deprecated.
> 
> Signed-off-by: Julius Werner <jwerner@chromium.org>
> ---
>  .../ddr/jedec,lpddr-channel.yaml              | 146 ++++++++++++++++++
>  .../ddr/jedec,lpddr-props.yaml                |  10 +-
>  2 files changed, 155 insertions(+), 1 deletion(-)
>  create mode 100644 Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr-channel.yaml
> 
> Changelog:
> 
> - v2:
>   - changed $ref for rank subnode to specifically match LPDDR type in
>     compatible string
>   - moved `reg` up to be listed right below `compatible`
> - v3:
>   - no changes
> - v4:
>   - no changes
> - v5:
>   - no changes
> 

Reviewed-by: Rob Herring <robh@kernel.org>