Subject: Re: [PATCH net-next] net: phy: let genphy_c45_read_link manage the devices to check

From: Andrew Lunn <[email-masked]>
Date: Thu, 7 Feb 2019 20:57:20 +0100

On Thu, Feb 07, 2019 at 08:05:55PM +0100, Heiner Kallweit wrote:
> Let genphy_c45_read_link manage the devices to check, this removes
> overhead from callers. Devices VEND1 and VEND2 will never be checked,
> for now adopt the logic of the Marvell driver to also exclude PHY XS.
> 
> At the moment we have very few clause 45 PHY drivers, so we are
> lacking experience whether other drivers will have to exclude further
> devices, or may need to check PHY XS. If we should figure out that
> list of devices to check needs to be configurable, I think best will
> be to add a device list member to struct phy_driver.

Hi Heiner

For the Aquantia PHY you probably need to exclude MDIO_MMD_C22EXT.

There is no register 1D:1 listed in the datasheet.

PHY XS is the interface towards the MAC. You cannot configure the MAC
to use the correct interface mode until the PHY has link to its peer
and the link mode has been determined. So you need the PHY to signal
link up independent of the MAC-PHY link, to kick off the configuration
of the MAC. When using phylink, the MAC can indicate it has a link to
the PHY using phylink_mac_change().

      Andrew