Re: [PATCH v14 00/15] phy: Add support for Lynx 10G SerDes

[Sean Anderson <sean.anderson@xxxxxxxx>]

On 8/21/23 19:59, Vladimir Oltean wrote:
> On Mon, Aug 21, 2023 at 07:39:15PM -0400, Sean Anderson wrote:
>> Well, I think we should take the opportunity to think about the hardware
>> which exists and how we plan to model it. IMO grouping lanes into a
>> single phy simplifies both the phy driver and the mac driver.
> 
> Ok, but ungrouped for backplane and grouped for !backplane? For the KR
> link modes, parallel link training, with separate consumers per lanes in
> a group, will be needed per lane.

Hm, this is the sort of thing I hadn't considered since separate link
training isn't necessary for lynx 10g. But couldn't this be done by
adding a "lane" parameter to phy_configure_opts_xgkr?

Although, I am not sure how the driver is supposed to figure out what
coefficients to use. c73 implies that the training frame should be sent
on each lane. So I expected that there would be four copies of the
link coefficient registers. However, when reading the LX2160ARM, I only
saw one set of registers (e.g. 26.6.3.3). So is link training done
serially? I didn't see anything like a "lane select" field.

--Sean