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

From: Thomas Petazzoni <[email-masked]>
Date: Fri, 2 Mar 2018 17:11:17 +0100

Hello,

On Fri,  2 Mar 2018 16:40:42 +0100, Antoine Tenart wrote:

> -/* Initialize Tx FIFO's */
> +/* Initialize Tx FIFO's
> + * The CP110's total tx-fifo size is 19kB.
> + * Use large-size 10kB for fast port but 3kB for others.
> + */

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 ?

It's just that it feels very "hardcoded" to enforce specifically those
numbers.

Also, does it make sense to mention the CP110 here ? Is this 19 KB
limitation a limit of the PPv2.2 IP, or of the CP110 ?

Thomas
-- 
Thomas Petazzoni, CTO, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
http://bootlin.com