Re: [PATCH net-next v3 0/5] net: stmmac: Add support for Allwinner A733 GMAC210

[Andrew Lunn <andrew@lunn.ch>]

> Thanks for the heads up. So if I'm reading the doc correctly the PHY
> adds 2ns
>  * on RX if there a 4.7k pull-up on RXD0
>  * on TX if there a 4.7k pull-up on RXD1
> 
> The schematics for the board are available here [1]
> 
> * 4.7k pull-up on RXD0: so we should have 2ns Rx from the PHY
> * 4.7k pull-down on RXD1: no idea what this does. Presumably no delay ?
> 
> I've cross-checked the HW, the resistors are actually fitted as the
> schematic says they are.
> 
> With the HW setup, the MAC setup that works for me remains
> 
> 	tx-internal-delay-ps = <1620>;
> 	rx-internal-delay-ps = <1800>;

These values suggests there are delays on both Rx an Tx.

> 
> I know it is not aligned with what it expected but still.

I'm flexible, if in the end this is what is required, that is fine. It
will need a comment explaining why it is needed, why the guidelines
are not being followed.

Where i have real problems is with developers who don't respect what
the guidelines say, even when their hardware could do what is
asked. They just do the minimum to make it work, and call it done.

The comment is then important, because i don't want developers using
this as an excuse not to do the correct thing.

     Andrew