[OpenWrt-Devel] b53: BCM5325 VLAN VID > 15 possible?

Jonas Gorski jogo at openwrt.org
Mon Sep 29 05:19:08 EDT 2014


On Mon, Sep 29, 2014 at 10:43 AM, Ilya Lipnitskiy
<ilya.lipnitskiy at gmail.com> wrote:
> Greetings!
> I have been trying to configure a NETGEAR WNDR3400 device to use VLAN ID 201
> on its WAN port to be able to talk to a Calix FTTH ONT. Studying the
> problem, I have found that the device contains a BCM5325 switch, which only
> supports up to 16 VLAN entries. However, each entry may have a VID that is
> 12 bits long, ie 0-4095.
> It does not seem that the current b53 driver supports this:
> From b53_common.c:
> static int b53_port_set_pvid(struct switch_dev *dev, int port, int val)
> {
> ...
>         if (val > 15 && is5325(priv))
>                 return -EINVAL;
> ...
> I don't think this is hardware limitation, as people seem to have gotten it
> to work in DD-WRT, see http://www.dd-wrt.com/phpBB2/viewtopic.php?t=86919.

This is a hardware limitation for BCM5325.

There are 16 entries (so 4 bit), which share a common 8-bit prefix.
The prefix can be set to an arbitrary value to "shift" the available
VIDs, but you are always limited to 16 consecutive VIDs. So you could
have VIDs 0-15, or 16-31, etc. Due to it (IMHO) being rather confusing
and easily braking network (e.g. you would need to change you lan VID
on changing it), I chose not to implement setting it.

Regarding the dd-wrt thread, as far as I could tell, they only allowed
using arbitrary VIDs for BCM53115, which is already supported fully by
the driver. For BCM5325 they added support for setting the prefix,
with the expected limitations.

openwrt-devel mailing list
openwrt-devel at lists.openwrt.org

More information about the openwrt-devel mailing list