Subject: Re: [net-next RFC PATCH v3 4/4] dt-bindings: Document bindings for Marvell Aquantia PHY

From: Christian Marangi <[email-masked]>
Date: Mon, 6 Nov 2023 17:47:20 +0100

On Fri, Nov 03, 2023 at 01:08:45PM +0000, Conor Dooley wrote:
> Yo,
> 
> On Thu, Nov 02, 2023 at 04:00:32PM +0100, Christian Marangi wrote:
> > Document bindings for Marvell Aquantia PHY.
> > 
> > The Marvell Aquantia PHY require a firmware to work correctly and there
> > at least 3 way to load this firmware.
> > 
> > Describe all the different way and document the binding "firmware-name"
> > to load the PHY firmware from userspace.
> > 
> > Signed-off-by: Christian Marangi <[email-masked]>
> > ---
> > Changes v3:
> > - Make DT description more OS agnostic
> > - Use custom select to fix dtbs checks
> > Changes v2:
> > - Add DT patch
> > 
> >  .../bindings/net/marvell,aquantia.yaml        | 126 ++++++++++++++++++
> >  1 file changed, 126 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/net/marvell,aquantia.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/net/marvell,aquantia.yaml b/Documentation/devicetree/bindings/net/marvell,aquantia.yaml
> > new file mode 100644
> > index 000000000000..d43cf28a4d61
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/net/marvell,aquantia.yaml
> > @@ -0,0 +1,126 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/net/marvell,aquantia.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Marvell Aquantia Ethernet PHY
> > +
> > +maintainers:
> > +  - Christian Marangi <[email-masked]>
> > +
> > +description: |
> > +  Marvell Aquantia Ethernet PHY require a firmware to be loaded to actually
> > +  work.
> > +
> > +  This can be done and is implemented by OEM in 3 different way:
> > +    - Attached SPI directly to the PHY with the firmware. The PHY will
> 
> You a word here? Should that not be "SPI flash"?
>

Added!

> > +      self load the firmware in the presence of this configuration.
> 
> > +    - Dedicated partition on system NAND with firmware in it. NVMEM
> > +      subsystem will be used and the declared NVMEM cell will load
> > +      the firmware to the PHY using the PHY mailbox interface.
> > +    - Manually provided firmware loaded from a file in the filesystem.
> > +
> > +  If declared, NVMEM will always take priority over filesystem provided
> > +  firmware.
> 
> This section here reads entirely like "software policy". The first
> bullet in your list is fine - as that is what the PHY will do itself.
> The second and third bullets here seem like two different ways that
> someone could integrate their system, and I am not objecting to either
> of those ways of doing things.
> The priority system that you mention however I don't think is suitable
> for a description of the hardware - the PHY itself doesn't require that
> an external-to-it flash device take priority over something in the
> filesystem, right?
> 

Yes the priority system is just something in software and nothing about
hardware. I dropped in v5. Thanks for the review!

-- 
	Ansuel