Re: [PATCH net-next v8 01/15] Documentation: ACPI: DSD: Document MDIO PHY

From: "Rafael J. Wysocki" <rafael@kernel.org>
To: Grant Likely <grant.likely@arm.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>,
	Ioana Ciornei <ciorneiioana@gmail.com>,
	Jeremy Linton <jeremy.linton@arm.com>,
	Andrew Lunn <andrew@lunn.ch>,
	Andy Shevchenko <andy.shevchenko@gmail.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Russell King - ARM Linux admin <linux@armlinux.org.uk>,
	Heikki Krogerus <heikki.krogerus@linux.intel.com>,
	Marcin Wojtas <mw@semihalf.com>,
	Pieter Jansen Van Vuuren <pieter.jansenvv@bamboosystems.io>,
	Jon <jon@solid-run.com>, Saravana Kannan <saravanak@google.com>,
	Randy Dunlap <rdunlap@infradead.org>,
	calvin.johnson@nxp.com,
	Cristi Sovaiala <cristian.sovaiala@nxp.com>,
	Florin Laurentiu Chiculita <florinlaurentiu.chiculita@nxp.com>,
	Madalin Bucur <madalin.bucur@nxp.com>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	Diana Madalina Craciun <diana.craciun@nxp.com>,
	ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	"linux.cj" <linux.cj@gmail.com>, netdev <netdev@vger.kernel.org>,
	Laurentiu Tudor <laurentiu.tudor@nxp.com>,
	Len Brown <lenb@kernel.org>,
	"Rafael J . Wysocki" <rjw@rjwysocki.net>,
	Calvin Johnson <calvin.johnson@oss.nxp.com>,
	Ioana Ciornei <ioana.ciornei@nxp.com>, "nd@arm.com" <nd@arm.com>
Subject: Re: [PATCH net-next v8 01/15] Documentation: ACPI: DSD: Document MDIO PHY
Date: Thu, 10 Jun 2021 20:31:38 +0200	[thread overview]
Message-ID: <CAJZ5v0g-NNJv=NBHxuUi6C0eJwOaZeU1nswEAuEaLciVD9wmFg@mail.gmail.com> (raw)
In-Reply-To: <070d33be-8056-d54c-05c1-a13432b3167e@arm.com>

On Thu, Jun 10, 2021 at 8:23 PM Grant Likely <grant.likely@arm.com> wrote:
>
> On 10/06/2021 19:05, Rafael J. Wysocki wrote:
> > On Thu, Jun 10, 2021 at 6:40 PM Ioana Ciornei <ciorneiioana@gmail.com> wrote:
> >>
> >> From: Calvin Johnson <calvin.johnson@oss.nxp.com>
> >>
> >> Introduce ACPI mechanism to get PHYs registered on a MDIO bus and
> >> provide them to be connected to MAC.
> >
> > This is not an "ACPI mechanism", because it is not part of the ACPI
> > specification or support documentation thereof.
> >
> > I would call it "a mechanism based on generic ACPI _DSD device
> > properties definition []1]".  And provide a reference to the _DSD
> > properties definition document.
> >
> > With that changed, you can add
> >
> > Acked-by: Rafael J. Wysocki <rafael@kernel.org>
> >
> > to this patch.
> >
> > Note, however, that within the traditional ACPI framework, the _DSD
> > properties are consumed by the driver that binds to the device
> > represented by the ACPI device object containing the _DSD in question
> > in its scope, while in this case IIUC the properties are expected to
> > be consumed by the general networking code in the kernel.  That is not
> > wrong in principle, but it means that operating systems other than
> > Linux are not likely to be using them.
> >
>
> Doesn't this land at the level of device drivers though? None of this
> data needs to be consumed by the OS generic ACPI parsing code, but the
> network device driver can use it to parse the MDIO and MAC configuraiton
> and set itself up appropriately.

That's right in general, which is why I said that doing it this way
wasn't wrong.