[U-Boot] [PATCH V1 1/3] phy: add phy_connect_by_mask

Troy Kisky
2012-08-22T19:59:32Z

On 8/20/2012 5:35 PM, Andy Fleming wrote:
>
>
> On Monday, August 20, 2012, Troy Kisky wrote:
>
> It is useful to be able to try a range of
> possible phy addresses to connect.
>
>
>
> This seems like it just encourages a bad habit.

Which is?

> How do you envision this working on a system with multiple Ethernet
> controllers? Or with more PHYs than Ethernet controllers?

The same way it works currently. I removed no features.

> While it is often the case that the PHY is the only one on a bus, I
> think it's a bad idea to codify that notion in the driver (I know, it
> was already like that).

So, should I fix something before this patch?

>
> It's best if the driver make the reasonable assumption that its PHY
> address is known when it comes up, and let the board code, which can
> be aware that the PHY may exist in varying locations, search for the PHY.

I agree. That's why I put
#define CONFIG_FEC_MXC_PHYMASK (0xf << 4) /* scan phy
4,5,6,7 */

in the boards config file.

> With that approach, the driver won't have to change when some board
> designer makes the PHY topology even stranger, and I would support a
> PHYLIB function to do searching much as you've specified. But the
> board-specific code needs to be able to tell the driver definitively
> which PHY belongs to it.

Please, will either you or Joe (or both!!!,) provide more specific
directions as I am currently floundering.

Thanks
Troy