RE: [PATCH net-next 3/5] net: mvpp2: use a data size of 10kB for Tx FIFO on port 0

[Stefan Chulski]

> -----Original Message-----
> From: Thomas Petazzoni [mailto:thomas.petazzoni@xxxxxxxxxxx]
> Sent: Sunday, March 04, 2018 11:25 AM
> To: Stefan Chulski <stefanc@xxxxxxxxxxx>
> Cc: Antoine Tenart <antoine.tenart@xxxxxxxxxxx>; davem@xxxxxxxxxxxxx;
> Yan Markman <ymarkman@xxxxxxxxxxx>; netdev@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; maxime.chevallier@xxxxxxxxxxx;
> gregory.clement@xxxxxxxxxxx; miquel.raynal@xxxxxxxxxxx; Nadav Haklai
> <nadavh@xxxxxxxxxxx>; mw@xxxxxxxxxxxx
> Subject: Re: [PATCH net-next 3/5] net: mvpp2: use a data size of 10kB for Tx
> FIFO on port 0
> 
> Hello,
> 
> On Sun, 4 Mar 2018 06:29:59 +0000, Stefan Chulski wrote:
> 
> > > Is there a reason to hardcode 10KB for port 0, and 3KB for the other ports
> ?
> > > Would there be use cases where the user may want different
> > > configurations ?
> >
> > Design requirement are 10KB TX FIFO for the 10Gb/sec and 2.5KB for the
> 2.5Gb/sec.
> 
> What is a "design requirement" ? Is it a HW design limitation ?

We can call it HW design limitation. Anyway to support 10Gb/sec port should have at least 10KB TX FIFO.

> So, the limitation has nothing to do with CP110 really, it's just a limitation of
> PPv2.2, and mentioning CP110 in the comment doesn't make much sense,
> correct ?

I will change it.

Stefan.