Re: [PATCH v3 net-next 5/8] net: dsa: felix: support psfp filter on vsc9959

[Vladimir Oltean]

On Tue, Aug 31, 2021 at 08:41:36AM +0000, Xiaoliang Yang wrote:
> Hi Vladimir,
>
> On Tue, Aug 31, 2021 at 15:55:26AM +0800, Vladimir Oltean wrote:
> > > +static int vsc9959_mact_stream_set(struct ocelot *ocelot,
> > > +				   struct felix_stream *stream,
> > > +				   struct netlink_ext_ack *extack) {
> > > +	struct ocelot_mact_entry entry;
> > > +	u32 row, col, reg, dst_idx;
> > > +	int ret;
> > > +
> > > +	/* Stream identification desn't support to add a stream with non
> > > +	 * existent MAC (The MAC entry has not been learned in MAC table).
> > > +	 */
> >
> > Who will add the MAC entry to the MAC table in this design? The user?
>
> Yes, The MAC entry is always learned by hardware, user also can add it
> by using "bridge fdb add".
>
> > So if the STREAMDATA entry for this SFID was valid, you mark the MAC table
> > entry as static, otherwise you mark it as ageable? Why?
>
> If the MAC entry is learned by hardware, it's marked as ageable. When
> setting the PSFP filter on this stream, it needs to be set to static.
> For example, if the MAC table entry is not set to static, when link is
> down for a period of time, the MAC entry will be forgotten, and SFID
> information will be lost.
> After disable PSFP filter on the stream, there is no need to keep the
> MAC entry static, setting the type back to ageable can cope with
> network topology changes.
>

So if the MAC table entry is ageable, will the TSN stream disappear from
hardware even though it is still present in tc?

I think in previous versions you were automatically installing a static
MAC table entry when one was not present (either it was absent, or the
entry was dynamically learned). Why did that change?