Re: [dpdk-dev] [PATCH v4 0/2] ethdev: add port speed capability bitmap

[Thomas Monjalon <thomas.monjalon@6wind.com>]

2015-09-13 21:14, Marc Sune:
> 2015-09-09 15:33 GMT+02:00 Thomas Monjalon <thomas.monjalon@6wind.com>:
> > 2015-09-09 15:10, Nélio Laranjeiro:
> > > I think V2 is better, maybe you can add a function to convert a single
> > > bitmap value to the equivalent integer and get rid of ETH_SPEED_XXX
> > macros.
> > >
> > > Thomas what is your opinion?
> >
> > Your proposal looks good Nelio.
> 
> I am confused, specially since you were the one advocating for having a
> unified set of constants for speeds (discussion in v2).

Yes, my first thought was advocating an unification between capabilities and
negotiated link properties.
After I was convinced by Nelio's arguments: bitmap is good for capabilities
(especially to describe every capabilities in one field) but integer is better
for negotiated speed (especially for aggregated links).
Converting bitmap speed into integer should be easy to implement in a function.

> In any case, as I see it, if we want to address the comments of  M. Brorup:
> 
> http://comments.gmane.org/gmane.comp.networking.dpdk.devel/19664
> 
> we need bitmaps for rte_eth_conf link_speed to set the advertised speeds.

Yes I forgot this interesting comment. It is saying we need
	1/ capabilities
	2/ advertised modes (for auto-negotiation or fixed config)
	3/ negotiated mode
Previously we were focused only on 1/ and 3/.
2/ was only limited to a mode configured without negotiation and was using the
same field as 3/.
Maybe we should really have 3 different fields. 1/ and 2/ would use a bitmap.

> Let me know if you really want to come back to v2 or not.

It needs more discussion. What do you think of the above proposal?
What is the opinion of Nelio? Morten?