Porting to a new board

[Sascha Hauer]

On Fri, Sep 20, 2013 at 04:02:44PM -0500, Allen Kennedy Jr. wrote:
> Thanks for the great idea to start with a loaded image in ram.
> 
> I was able to get it to run, but I can't get the Ethernet to work.
> I'm not entirely sure where to begin looking.
> 
> I hit devinfo and get:
> <snip>
>      `---- imx27-fec
>           `---- miibus0
>           `---- eth0
> <...>
> drivers:
> <...>
> SMSC LAN83C185
> SMSC LAN8187
> SMSC LAN8700
> SMSC LAN911x Internal PHY
> SMSC LAN8710/LAN8720
> fec_imx
> Generic PHY
> </snip>
> 
> This would seem to indicate to me that the drivers are loading. And
> that the register happened.
> But I'm not sure where to go from here.

What's the output of some network command, like for example 'dhcp'?

What's the output of 'md -w -s /dev/phy0'?

Problems with networking usually go down to problems with the phy.
What's the content of the platform data for the FEC? It should look
like:

static struct fec_platform_data fec_info = {
        .xcv_type = PHY_INTERFACE_MODE_MII,
        .phy_addr = -1,
};


With xcv_type being MII (I think it's the only possibility on i.MX27)
and phy_addr to either -1 for autodetecting the address or the correct
address. Use -1 to be on the safe side.

When 'md -w -s /dev/phy0' doesn't show any sensible register output then
your pinmux may be wrong or you haven't brought your phy out of reset
with some gpio.

> 
> In another thread... the advice was given to check the MII address,
> although I'm not sure how to interpret the data sheet.
> It looks as though the address is 31.  But I could be wrong.  When I
> try 31, and do a DHCP the processor hangs.
> So I tried 0, and the processor hangs.
> 
> Is there a "scan the bus mode" I can use in the fec driver?  I don't
> see one, but I may be looking in the wrong spot.

It's not in the FEC driver but in the generic MII support. As said, use
-1 as phy id.

Sascha

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