On Wed, 24 Nov 2021 14:31:35 +0200 Vladimir Oltean <olteanv@xxxxxxxxx> wrote: > > > To err is human, of course. But one thing I think we learned from the > > > old implementation of phylink_validate is that it gets very tiring to > > > keep adding PHY modes, and we always seem to miss some. When that array > > > will be described in DT, it could be just a tad more painful to maintain. > > > > The thing is that we will still need the `phy-mode` property, it can't > > be deprecated IMO. > > Wait a minute, who said anything about deprecating it? I just said > "let's not make it an array, in the actual device tree". The phy-mode > was, and will remain, the initial MII-side protocol, which can or cannot > be changed at runtime. Hello Vladimir, I was told multiple times that device-tree should not specify how the software should behave (given multiple HW options). This has not been always followed, but it is preferred. Now the 'phy-mode' property, if interpreted as "the initial MII-side protocol" would break this rule. This is therefore another reason why it should either be extended to an array, or, if we went with your proposal of 'num-lanes' + 'max-freq', deprecated (at least for serdes modes). But it can't be deprecated entirely, IMO (because of non serdes protocols). I thought more about your proposal of 'num-lanes' + 'max-freq' vs extending 'phy-mode'. - 'num-lanes' + 'max-freq' are IMO closer to the idea of device-tree, since they describe exactly how the parts of the device are connected to each other - otherwise I think your argument against extending 'phy-mode' because of people declaring support for modes that weren't properly tested and would later be found broken is invalid, since the same could happen for 'num-lanes' + 'max-freq' properties - the 'phy-mode' property already exists. I think if we went with the 'num-lanes' + 'max-freq' proposal, we would need to deprecate 'phy-mode' for serdes protocols (at least for situations where multiple modes can be used, since then 'phy-mode' would go against the idea of the rule I mentioned in first paragraph) Vladimir, Rob has now given R-B for the 'phy-mode' extension patch. I am wondering now what to do, since other people haven't given their opinions here. Whether to re-send the series, and maybe start discussing there, or waiting more. Marek
