Re: [Bridge] Re: [PATCH] (6/6) bridge: receive path optimization

["Atul Sabharwal" <iamatul@xxxxxxxxxxx>]

I have a question about using the 802.1d driver with a switch.  I have a 
managed switch
which connects to the Xscale MAC using a Reverse MII interface.

It seems that the 802.1d bridge puts the interface into promiscuous mode and 
needs multiple
ethernet devices to work with.  Can it work with a single ethernet device 
which is connected
to a BCM5338 ( broadcomm 8 port switch chip ).

I understand that I would have to change the STP configuration component to 
write to the
broadcomm chip.

The chip supports direct memory mapped I/O of BPDU's using polled 
xmite/recieve using
a SPI interface.  Since I use a soft SPI stack, I cannot go faster than 
2MHz. Besides this
is a serial interface.

Suggestion, comments on both choices are highly appreciated.  I am working 
in a custom
enviornment with main objective of detecting loops in a cascade of switches. 
The physical
interconnect of the switches could be linear, tree, star or graph topology.

Also, the spanning tree needs to reconverge when switches are 
connected/disconnected.
Since there are no interrupts from the BCM5338, most of the implementation 
would be
based of polling.  Maybe, a forwarding delay of 5s should work as this is a 
LAN environment.

--
Atul
Linux Engineer