Re: [RFC PATCH 08/10] net: dsa: b53: fix unicast/multicast flooding on BCM5325

[Álvaro Fernández Rojas]

Hi Jonas,

El lun, 2 jun 2025 a las 22:08, Jonas Gorski
(<jonas.gorski@xxxxxxxxx>) escribió:
>
> On Mon, Jun 2, 2025 at 8:09 PM Florian Fainelli
> <florian.fainelli@xxxxxxxxxxxx> wrote:
> >
> > On 5/31/25 03:13, Álvaro Fernández Rojas wrote:
> > > BCM5325 doesn't implement UC_FLOOD_MASK, MC_FLOOD_MASK and IPMC_FLOOD_MASK
> > > registers.
> > > This has to be handled differently with other pages and registers.
> > >
> > > Fixes: a8b659e7ff75 ("net: dsa: act as passthrough for bridge port flags")
> > > Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
> > > ---
> >
> > [snip]
> >
> > > +/*************************************************************************
> > > + * IEEE 802.1X Registers
> > > + *************************************************************************/
> > > +
> > > +/* Multicast DLF Drop Control register (16 bit) */
> > > +#define B53_IEEE_MCAST_DLF           0x94
> > > +#define B53_IEEE_MCAST_DROP_EN               BIT(11)
> > > +
> > > +/* Unicast DLF Drop Control register (16 bit) */
> > > +#define B53_IEEE_UCAST_DLF           0x96
> > > +#define B53_IEEE_UCAST_DROP_EN               BIT(11)
> >
> > Are you positive the 5325 implements all of those registers? They are
> > not documented in my databook.
>
> They are in 5325E-DS14-R pages 112 - 112 (134/135)
>
> That being said, I don't thing we need to touch the MC/BC/DLF rate
> control registers when enabling/disabling flooding - these only limit
> how much traffic may be UC / MC  on a port, but apart from that they
> do not limit flooding. We don't limit this on other switch models
> either.

In that case there's nothing to enable/disable on the BCM5325 and we
should do an early return on b53_port_set_ucast_flood and
b53_port_set_mcast_flood since UC_FLOOD_MASK, MC_FLOOD_MASK and
IPMC_FLOOD_MASK don't exist.

>
> Regards,
> Jonas

Best regards,
Álvaro.