Re: [PATCH V3] net/dt: Add support for overriding phy configurationfrom device tree

[Florian Fainelli]

2014-01-19 Ben Hutchings <ben@xxxxxxxxxxxxxxx>:
> On Fri, 2014-01-17 at 17:57 -0500, Matthew Garrett wrote:
>> Some hardware may be broken in interesting and board-specific ways, such
>> that various bits of functionality don't work. This patch provides a
>> mechanism for overriding mii registers during init based on the contents of
>> the device tree data, allowing board-specific fixups without having to
>> pollute generic code.
> [...]
>> --- a/Documentation/devicetree/bindings/net/phy.txt
>> +++ b/Documentation/devicetree/bindings/net/phy.txt
>> @@ -23,6 +23,21 @@ Optional Properties:
>>    assume clause 22. The compatible list may also contain other
>>    elements.
>>
>> +The following properties may be added to either the phy node or the parent
>> +ethernet device. If not present, the hardware defaults will be used.
>> +
>> +- phy-mii-advertise-10half: 1 to advertise half-duplex 10MBit, 0 to disable
>> +- phy-mii-advertise-10full: 1 to advertise full-duplex 10MBit, 0 to disable
>> +- phy-mii-advertise-100half: 1 to advertise half-duplex 100MBit, 0 to disable
>> +- phy-mii-advertise-100full: 1 to advertise full-duplex 100MBit, 0 to disable
>> +- phy-mii-advertise-100base4: 1 to advertise 100base4, 0 to disable
>> +- phy-mii-advertise-1000half: 1 to advertise half-duplex 1000MBit, 0 to disable
>> +- phy-mii-advertise-1000full: 1 to advertise full-duplex 1000MBit, 0 to disable
>
> Are these really all needed?  Apparently there is a standard 'max-speed'
> property on Ethernet devices already, which I think is probably
> sufficient to express the actual restrictions of some boards.

This is what I think as well. Maybe there is the need for something
more fine-grained, although I really doubt it.

>
>> +- phy-mii-manual-master: 1 to enable manual master/slave configuration, 0
>> +  to disable manual master/slave configuration
> [...]
>
> Although the standard calls this 'manual', if it's set in the DT it
> won't really be a manual setting.  The description should probably
> clarify that.
>
> I think the name should include 'master-slave' or 'clock-role' rather
> than just 'master', as currently it suggests only the master role can be
> forced.

Right, and this would match what 802.3-2008, Section 22.2.4.3.7 mentions.

>
> Ben.
>
> --
> Ben Hutchings
> friends: People who know you well, but like you anyway.



-- 
Florian
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