RE: [EXT] Re: [PATCH v6 3/3] net: dsa: ocelot: Add support for QinQ Operation

[Hongbo Wang]

Hi Vladimir,

> 
> I asked this on the Microchip Support portal:
> 
> -----------------------------[cut here]-----------------------------
> 
> VLAN filtering only on specific TPID
> ------------------------------------
> 
> I would like to configure a port with the following behavior:
> - The VLAN table should contain 802.1ad VLANs 1 and 10. VLAN ingress
> filtering
>   should be enabled.
> - An untagged frame on ingress should be classified to 802.1ad (TAG_TYPE=1)
>   VLAN ID 1 (the port-based VLAN). The frame should be accepted because
> 802.1ad
>   VLAN 1 is in the VLAN table.
> - An ingress frame with 802.1Q (0x8100) header VLAN ID 100 should be
> classified
>   to 802.1ad (TAG_TYPE=1) VLAN ID 1 (the port-based VLAN). The frame
> should be
>   accepted because 802.1ad VLAN 1 is in the VLAN table.
> - An ingress frame with 802.1ad (0x88a8) header VLAN ID 10 should be
> classified
>   to 802.1ad (TAG_TYPE=1) VLAN ID 10. The frame should be accepted
> because
>   802.1ad VLAN 10 is in the VLAN table.
> - An ingress frame with 802.1ad (0x88a8) header VLAN ID 100 should be
>   classified to 802.1ad (TAG_TYPE=1) VLAN ID 100. The frame should be
> dropped
>   because 802.1ad VLAN 100 is not in the VLAN table.
> How do I configure the switch to obtain this behavior? This is not what the
> "Provider Bridges and Q-in-Q Operation" chapter in the reference manual is
> explaining how to do. Instead, that chapter suggests to make
> VLAN_CFG.VLAN_AWARE_ENA = 0. But I don't want to do this, because I need
> to be able to drop the frames with 802.1ad VLAN ID 100 in the example above.
> 
> -----------------------------[cut here]-----------------------------
> 
> Judging from the fact that I received no answer whatsoever, I can only deduce
> that offloading an 8021ad bridge, at least one that has the semantics that
> Toshiaki Makita described here,
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgit.kern
> el.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Fnetdev%2Fnet-next.git%2F
> commit%2F%3Fid%3D1a0b20b257326523ec2a6cb51dd6f26ef179eb84&
> data=02%7C01%7Chongbo.wang%40nxp.com%7Cdcfd5e5df4e24455726408d
> 86c4f0493%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C6373784
> 33917654330&sdata=kk8WnA0iH9E5yPrLKC8BwSInD6jqm0qGftJ8Jw1Etk
> 8%3D&reserved=0
> is not possible with this hardware.
> 
> So I think there's little left to do here.
> 
> If it helps, I am fairly certain that the sja1105 can offer the requested services,
> if you play a little bit with the TPID and TPID2 values. Maybe that's a path
> forward for your patches, if you still want to add the generic support in
> switchdev and in DSA.
> 

Thanks for your suggestion,
I will research the related code, and will optimize my patches.

Thanks,
hongbo