linux/net/dsa
Vladimir Oltean 8ded916092 net: dsa: tag_sja1105: stop asking the sja1105 driver in sja1105_xmit_tpid
Introduced in commit 38b5beeae7 ("net: dsa: sja1105: prepare tagger
for handling DSA tags and VLAN simultaneously"), the sja1105_xmit_tpid
function solved quite a different problem than our needs are now.

Then, we used best-effort VLAN filtering and we were using the xmit_tpid
to tunnel packets coming from an 8021q upper through the TX VLAN allocated
by tag_8021q to that egress port. The need for a different VLAN protocol
depending on switch revision came from the fact that this in itself was
more of a hack to trick the hardware into accepting tunneled VLANs in
the first place.

Right now, we deny 8021q uppers (see sja1105_prechangeupper). Even if we
supported them again, we would not do that using the same method of
{tunneling the VLAN on egress, retagging the VLAN on ingress} that we
had in the best-effort VLAN filtering mode. It seems rather simpler that
we just allocate a VLAN in the VLAN table that is simply not used by the
bridge at all, or by any other port.

Anyway, I have 2 gripes with the current sja1105_xmit_tpid:

1. When sending packets on behalf of a VLAN-aware bridge (with the new
   TX forwarding offload framework) plus untagged (with the tag_8021q
   VLAN added by the tagger) packets, we can see that on SJA1105P/Q/R/S
   and later (which have a qinq_tpid of ETH_P_8021AD), some packets sent
   through the DSA master have a VLAN protocol of 0x8100 and others of
   0x88a8. This is strange and there is no reason for it now. If we have
   a bridge and are therefore forced to send using that bridge's TPID,
   we can as well blend with that bridge's VLAN protocol for all packets.

2. The sja1105_xmit_tpid introduces a dependency on the sja1105 driver,
   because it looks inside dp->priv. It is desirable to keep as much
   separation between taggers and switch drivers as possible. Now it
   doesn't do that anymore.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-25 11:14:34 +01:00
..
dsa2.c net: dsa: track unique bridge numbers across all DSA switch trees 2021-08-23 11:52:31 +01:00
dsa_priv.h net: dsa: don't advertise 'rx-vlan-filter' when not needed 2021-08-24 09:30:58 +01:00
dsa.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
Kconfig net: dsa: tag_sja1105: be dsa_loop-safe 2021-08-18 10:33:15 +01:00
Makefile net: dsa: build tag_8021q.c as part of DSA core 2021-07-20 06:36:42 -07:00
master.c dev_ioctl: split out ndo_eth_ioctl 2021-07-27 20:11:45 +01:00
port.c net: dsa: don't advertise 'rx-vlan-filter' when not needed 2021-08-24 09:30:58 +01:00
slave.c net: dsa: let drivers state that they need VLAN filtering while standalone 2021-08-24 09:30:58 +01:00
switch.c net: dsa: let drivers state that they need VLAN filtering while standalone 2021-08-24 09:30:58 +01:00
tag_8021q.c net: dsa: tag_8021q: fix notifiers broadcast when they shouldn't, and vice versa 2021-08-16 11:14:18 +01:00
tag_ar9331.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_brcm.c net: dsa: create a helper for locating EtherType DSA headers on RX 2021-08-11 14:44:58 +01:00
tag_dsa.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_gswip.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_hellcreek.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_ksz.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_lan9303.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_mtk.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_ocelot_8021q.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_ocelot.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_qca.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_rtl4_a.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_sja1105.c net: dsa: tag_sja1105: stop asking the sja1105 driver in sja1105_xmit_tpid 2021-08-25 11:14:34 +01:00
tag_trailer.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_xrs700x.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00