Re: [PATCH net-next 2/3] net: dsa: add Arrow SpeedChips XRS700x driver

[Andrew Lunn <andrew@lunn.ch>]

> > > https://www.flexibilis.com/downloads/xrs/SpeedChip_XRS7000_3000_User_Manual.pdf

Section 6.1.4

The forwarding decision is presented in Figure 19. Note that also
frames coming into a disabled port are received to the buffer memory,
but because their forwarding decision is not to forward them to any
port, they are dropped.  This behavior however can be changed, and
frames can be forwarded from disabled ports to other ports by using
Inbound Policy (see Chapter 6.1.5).

Sounds promising. And Section 6.1.5:

Inbound Policy checks the source and the destination MAC addresses of
all the received frames. The user can configure through the register
interface what kind of a treatment should frames with certain source
or destination MAC addresses get. Many protocols use protocol specific
multicast MAC addresses and the destination MAC address can therefore
be used for forwarding those frames to CPU port and not to other
ports.

Looking at table 36, i think you can add a match for the BPDU
destination MAC address, and have i forwarded to the CPU port.

Looks like you can add 15 such filters. So you might want to think
about how you want to use these, what other special packets do you
want to allow through?

	    Andrew