# RE: \[EXT\] Re: \[PATCH RFC net-next 00/19\] net: mvpp2: Add TX Flow Control support

- From: Stefan Chulski \<hidden\>
- Date: 2021-01-10 19:13:04 
- List: netdev
- Page: https://ratatoskr.run/netdev/2021/01/6228994
- Thread: https://ratatoskr.run/netdev/2021/01/6228879/t.md

```text
> 
> On Sun, Jan 10, 2021 at 06:55:11PM +0000, Stefan Chulski wrote:
> > > > not connected to the GOP flow control generation mechanism.
> > > > To solve this issue Armada has firmware running on CM3 CPU
> > > > dedectated for Flow Control support. Firmware monitors Packet
> > > > Processor resources and asserts XON/XOFF by writing to Ports Control 0
> Register.
> > >
> > > What is the minimum firmware version that supports this?
> > >
> >
> > Support were added to firmware about two years ago.
> > All releases from 18.09 should has it.
> 
> Can you query the firmware and ask its version? We should keep all this code
> disabled if the firmware it too old.
> 
>      Andrew

This is exactly what " net: mvpp2: add TX FC firmware check " patch do. If handshake of flow control support fail, FC won't be supported.

Stefan. 
```