Re: [PATCH v4 net-next 00/19] net: mvpp2: Add TX Flow Control support

From: Marcin Wojtas
Date: Thu Jan 28 2021 - 11:49:45 EST


czw., 28 sty 2021 o 17:43 Russell King - ARM Linux admin
<linux@xxxxxxxxxxxxxxx> napisał(a):
>
> On Wed, Jan 27, 2021 at 01:43:16PM +0200, stefanc@xxxxxxxxxxx wrote:
> > Armada hardware has a pause generation mechanism in GOP (MAC).
> > The GOP generate flow control frames based on an indication programmed in Ports Control 0 Register. There is a bit per port.
> > However assertion of the PortX Pause bits in the ports control 0 register only sends a one time pause.
> > To complement the function the GOP has a mechanism to periodically send pause control messages based on periodic counters.
> > This mechanism ensures that the pause is effective as long as the Appropriate PortX Pause is asserted.
>
> I've tested this on my Macchiatobin SingleShot, which seems to be Ax
> silicon (and I've checked a couple of my other Armada 8040 platforms
> which are also Ax silicon too) and networking remains functional
> without flow control with the gigabit port achieving wire speed. I
> have not yet tested the 10G ports.
>
> --

Thanks Russell.

I'll stress and verify CN913x platform with the appropriate firmware.
This should happen after the weekend, as I don't have an immediate
access to our lab in order to replug the cables. I'll update here
about the results.

Best regards,
Marcin