[PATCH net-next] net: dsa: mt7530: support MDB and bridge flag operations

[Vladimir Oltean]

On Mon, Mar 15, 2021 at 01:03:10PM -0700, Florian Fainelli wrote:
> 
> 
> On 3/15/2021 10:09 AM, DENG Qingfang wrote:
> > Support port MDB and bridge flag operations.
> > 
> > As the hardware can manage multicast forwarding itself, offload_fwd_mark
> > can be unconditionally set to true.
> > 
> > Signed-off-by: DENG Qingfang <dqfext at gmail.com>
> > ---
> > Changes since RFC:
> >   Replaced BR_AUTO_MASK with BR_FLOOD | BR_LEARNING
> > 
> >  drivers/net/dsa/mt7530.c | 124 +++++++++++++++++++++++++++++++++++++--
> >  drivers/net/dsa/mt7530.h |   1 +
> >  net/dsa/tag_mtk.c        |  14 +----
> >  3 files changed, 122 insertions(+), 17 deletions(-)
> > 
> > diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
> > index 2342d4528b4c..f765984330c9 100644
> > --- a/drivers/net/dsa/mt7530.c
> > +++ b/drivers/net/dsa/mt7530.c
> > @@ -1000,8 +1000,9 @@ mt753x_cpu_port_enable(struct dsa_switch *ds, int port)
> >  	mt7530_write(priv, MT7530_PVC_P(port),
> >  		     PORT_SPEC_TAG);
> >  
> > -	/* Unknown multicast frame forwarding to the cpu port */
> > -	mt7530_rmw(priv, MT7530_MFC, UNM_FFP_MASK, UNM_FFP(BIT(port)));
> > +	/* Disable flooding by default */
> > +	mt7530_rmw(priv, MT7530_MFC, BC_FFP_MASK | UNM_FFP_MASK | UNU_FFP_MASK,
> > +		   BC_FFP(BIT(port)) | UNM_FFP(BIT(port)) | UNU_FFP(BIT(port)));
> 
> It's not clear to me why this is appropriate especially when the ports
> operated in standalone mode, can you expand a bit more on this?

We are in the function called "mt753x_cpu_port_enable" here. It's ok to
apply this config for the CPU port.