[PATCH v2 1/2] ARM: at91/dt: describe rgmii ethernet phy connected to sama5d3xek boards

Nicolas Ferre nicolas.ferre at atmel.com
Fri Jun 27 00:52:56 PDT 2014

On 26/06/2014 22:01, Boris BREZILLON :
> Hi Florian,
> On 26/06/2014 20:15, Florian Fainelli wrote:
>> Hi Boris,
>> 2014-06-26 3:13 GMT-07:00 Boris BREZILLON <boris.brezillon at free-electrons.com>:
>>> Add ethernet-phy node and specify phy interrupt (connected to pin PB25).
>>> The PHY address is not specified here because atmel have 2 different
>>> designs
>>> for its CPU modules: one is connecting PHYAD[0-2] pins to pull up resistors
>>> (Embest design) and the other one is connection PHYAD0 to a pull up
>>> resistor and PHYAD[1-2] to pull down resistors (Ronetix design).
>>> As a result, Ronetix design will have its PHY available at address 0x1 and
>>> Embest design at 0x7.
>>> Let the net PHY core automatically detect the PHY address by scanning the
>>> MDIO bus.
>> I though the compatible string was listed as a required property, but
>> it is not. The 'reg' property however is listed as required, although
>> the of_miodbus_register() works just fine without it, although that is
>> a Linux-specific implementation detail.
> Indeed, it's listed in the required property list of the DT binding doc,
> but the code implement auto detection if reg is missing.
> However this line [1] clearly shows that specifying the reg property is
> the preferred way of doing things.
> I could define 2 different sama5d3xcm.dtsi (sama5d3xcm-ronetix.dtsi and
> sama5d3xcm-embest.dtsi) to avoid this dirty hack,
> but then we would have 2 more dtb and the user would have to determine
> which CPU module he owns to choose the appropriate dtb.
> If at91, arm-soc and DT maintainers agree with this approach I can
> definitely propose something.

Yes Boris, I definitively prefer not to add another .dtsi file for this
series if we can avoid it.

So, I would push for this "reg-less" solution. If it is chosen, you can
add my:
Acked-by: Nicolas Ferre <nicolas.ferre at atmel.com>

Thanks, bye.

>>> Define board specific delays to apply to RGMII signals.
>>> Signed-off-by: Boris BREZILLON <boris.brezillon at free-electrons.com>
>> Reviewed-by: Florian Fainelli <f.fainelli at gmail.com>
> Thanks for your review.
> Best Regards,
> Boris
> [1] http://lxr.free-electrons.com/source/drivers/of/of_mdio.c#L187

Nicolas Ferre

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