Re: [PATCH net-next 2/3] net: nixge: Add support for having nixge as subdevice

From: Moritz Fischer
Date: Thu Aug 30 2018 - 12:39:43 EST

Hi Andrew,

On Wed, Aug 29, 2018 at 8:11 PM, Andrew Lunn <andrew@xxxxxxx> wrote:

> Could you tell us more about the parent device. I'm guessing PCIe. Is
> it x86 so no device tree? Are there cases where it does not have a PHY
> connected? What is connected instead? SFP? A switch? Can there be
> multiple PHYs on the MDIO bus?

The device is part of a larger FPGA design. One use case that I was trying
to support with this patch is PCIe with x86 (hopefully on it's own PF...)
Since the whole design isn't completely done, these are the use cases I
see upcoming and current:

a) DT: PHY over MDIO (current use case), fixed-link with GPIO (coming)
b) DT: SFP (potentially coming)

a) no PHY (coming)-> fixed-link with GPIO
b) SFP (potentially), PHY over MDIO (potentially)

Thanks for your help,