Re: [PATCH net-next 25/30] net: dsa: mt7530: properly set MT7531_CPU_PMAP

[Vladimir Oltean]

On Sun, Jun 04, 2023 at 11:21:48AM +0300, Arınç ÜNAL wrote:
> > Stylistically, the existence of an indirect call to priv->info->cpu_port_config()
> > per switch family is a bit dissonant with an explicit check for device id later
> > in the same function.
> 
> mt753x_cpu_port_enable() is not being called from priv->info->cpu_port_config()
> though.

Quite the other way around. I'm saying that mt753x_cpu_port_enable(),
the function whose logic you're changing, already has a mechanism to
execute code specific to one switch family.

> I'm not sure how I would do this without the device ID check here.

Hmm, by defining a new mt7530_cpu_port_config() procedure for ID_MT7621
and ID_MT7530?

Although in a different thread we are perhaps challenging the idea that
what is currently in priv->info->cpu_port_config() is useful - at least
half of it are manual invocations of phylink methods which are possibly
not needed. If after the removal of those, it no longer makes sense to
have priv->info->cpu_port_config() at all, then I'm not saying that the
explicit check for device id here doesn't make sense. Just that it's not
in harmony with what currently exists 3 lines above.

> > > -#define  MT7531_CPU_PMAP_MASK		GENMASK(7, 0)
> > > +#define  MT7531_CPU_PMAP(x)		((x) & 0xff)
> > 
> > You can leave this as ((x) & GENMASK(7, 0))
> 
> Now that I've read Russell's comment on the previous patch, the below would
> be even better?
> 
> MT7531_CPU_PMAP(x)		FIELD_PREP(MT7531_CPU_PMAP_MASK, x)
> 
> > 
> > > +#define  MT7531_CPU_PMAP_MASK		MT7531_CPU_PMAP(~0)
> > 
> > There's no other user of MT7531_CPU_PMAP_MASK, you can remove this.
> 
> Should I do above or remove this?

No specific preference. If you want to make this driver start using
FIELD_PREP() then go ahead.