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

[Vladimir Oltean]

On Wed, Feb 24, 2021 at 04:10:18PM +0800, 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:
> Add bridge flag operations and resend as RFC
> 
>  drivers/net/dsa/mt7530.c | 123 +++++++++++++++++++++++++++++++++++++--
>  drivers/net/dsa/mt7530.h |   1 +
>  net/dsa/tag_mtk.c        |  14 +----
>  3 files changed, 121 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
> index bca4fc724e45..341a6b3f7ef6 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 */

I think the comment is incorrect and this _enables_ flooding (which btw
is ok until we get the address filtering thing sorted out).

> +	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)));
>  
>  	/* Set CPU port number */
>  	if (priv->id == ID_MT7621)
> @@ -1138,6 +1139,55 @@ mt7530_stp_state_set(struct dsa_switch *ds, int port, u8 state)
>  	mt7530_rmw(priv, MT7530_SSP_P(port), FID_PST_MASK, stp_state);
>  }
>  
> +static int
> +mt7530_port_pre_bridge_flags(struct dsa_switch *ds, int port,
> +			     struct switchdev_brport_flags flags,
> +			     struct netlink_ext_ack *extack)
> +{
> +	if (flags.mask & ~(BR_AUTO_MASK | BR_MCAST_FLOOD | BR_BCAST_FLOOD))
> +		return -EINVAL;

I think BR_AUTO_MASK is confusing (because it is internal to the bridge
layer) and could be better expressed as BR_FLOOD | BR_LEARNING.

> +
> +	return 0;
> +}
> +