[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAHp75Vdn=t2UQpCP_kpOyyX_L6kvJ-=vtWp2t87PbYBbJOczTA@mail.gmail.com>
Date: Thu, 18 Jun 2020 19:00:20 +0300
From: Andy Shevchenko <andy.shevchenko@...il.com>
To: Jeremy Linton <jeremy.linton@....com>
Cc: Andrew Lunn <andrew@...n.ch>,
Calvin Johnson <calvin.johnson@....nxp.com>,
Russell King - ARM Linux admin <linux@...linux.org.uk>,
Jon <jon@...id-run.com>,
Cristi Sovaiala <cristian.sovaiala@....com>,
Ioana Ciornei <ioana.ciornei@....com>,
Florian Fainelli <f.fainelli@...il.com>,
Madalin Bucur <madalin.bucur@....nxp.com>,
netdev <netdev@...r.kernel.org>, linux.cj@...il.com
Subject: Re: [PATCH v1 2/3] net/fsl: acpize xgmac_mdio
On Thu, Jun 18, 2020 at 6:46 PM Jeremy Linton <jeremy.linton@....com> wrote:
> On 6/17/20 12:34 PM, Andrew Lunn wrote:
> > On Wed, Jun 17, 2020 at 10:45:34PM +0530, Calvin Johnson wrote:
> >> From: Jeremy Linton <jeremy.linton@....com>
> >
> >> +static const struct acpi_device_id xgmac_acpi_match[] = {
> >> + { "NXP0006", (kernel_ulong_t)NULL },
> >
> > Hi Jeremy
> >
> > What exactly does NXP0006 represent? An XGMAC MDIO bus master? Some
> > NXP MDIO bus master? An XGMAC Ethernet controller which has an NXP
> > MDIO bus master? A cluster of Ethernet controllers?
>
> Strictly speaking its a NXP defined (they own the "NXP" prefix per
> https://uefi.org/pnp_id_list) id. So, they have tied it to a specific
> bit of hardware. In this case it appears to be a shared MDIO master
> which isn't directly contained in an Ethernet controller. Its somewhat
> similar to a "nxp,xxxxx" compatible id, depending on how they are using
> it to identify an ACPI device object (_HID()/_CID()).
>
> So AFAIK, this is all valid ACPI usage as long as the ID maps to a
> unique device/object.
>
> >
> > Is this documented somewhere? In the DT world we have a clear
> > documentation for all the compatible strings. Is there anything
> > similar in the ACPI world for these magic numbers?
>
> Sadly not fully. The mentioned PNP and ACPI
> (https://uefi.org/acpi_id_list) ids lists are requested and registered
> to a given organization. But, once the prefix is owned, it becomes the
> responsibility of that organization to assign & manage the ID's with
> their prefix. There are various individuals/etc which have collected
> lists, though like PCI ids, there aren't any formal publishing requirements.
And here is the question, do we have (in form of email or other means)
an official response from NXP about above mentioned ID?
--
With Best Regards,
Andy Shevchenko
Powered by blists - more mailing lists