| Message ID | 20210121023616.1696021-1-olteanv@gmail.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | tag_8021q for Ocelot switches | expand |
On 1/20/2021 6:36 PM, Vladimir Oltean wrote: > From: Vladimir Oltean <vladimir.oltean@nxp.com> > > Context: Ocelot switches put the injection/extraction frame header in > front of the Ethernet header. When used in NPI mode, a DSA master would > see junk instead of the destination MAC address, and it would most > likely drop the packets. So the Ocelot frame header can have an optional > prefix, which is just "ff:ff:ff:ff:ff:fe > ff:ff:ff:ff:ff:ff" padding > put before the actual tag (still before the real Ethernet header) such > that the DSA master thinks it's looking at a broadcast frame with a > strange EtherType. > > Unfortunately, a lesson learned in commit 69df578c5f4b ("net: mscc: > ocelot: eliminate confusion between CPU and NPI port") seems to have > been forgotten in the meanwhile. > > The CPU port module and the NPI port have independent settings for the > length of the tag prefix. However, the driver is using the same variable > to program both of them. > > There is no reason really to use any tag prefix with the CPU port > module, since that is not connected to any Ethernet port. So this patch > makes the inj_prefix and xtr_prefix variables apply only to the NPI > port (which the switchdev ocelot_vsc7514 driver does not use). > > Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
On 1/20/2021 6:36 PM, Vladimir Oltean wrote: > From: Vladimir Oltean <vladimir.oltean@nxp.com> > > The existence of dsa_broadcast has generated some confusion in the past: > https://www.mail-archive.com/netdev@vger.kernel.org/msg365042.html > > So let's document the existing dsa_port_notify and dsa_broadcast > functions and explain when each of them should be used. > > Also, in fact, the in-between function has always been there but was > lacking a name, and is the main reason for this patch: dsa_tree_notify. > Refactor dsa_broadcast to use it. > > This patch also moves dsa_broadcast (a top-level function) to dsa2.c, > where it really belonged in the first place, but had no companion so it > stood with dsa_port_notify. > > Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
From: Vladimir Oltean <vladimir.oltean@nxp.com> Changes in v5: - Split patch series in half, removing PTP bits. - Split previous monolithic patch "net: dsa: felix: add new VLAN-based tagger" into 3 smaller patches. - Updated the sysfs documentation - Made the tagger_lock per DSA switch tree instead of per DSA switch - Using dsa_tree_notify instead of dsa_broadcast. Changes in v4: - Support simultaneous compilation of tag_ocelot.c and tag_ocelot_8021q.c. - Support runtime switchover between the two taggers, by using echo ocelot-8021q > /sys/class/net/eno2/dsa/tagging - We are now actually performing cleanup instead of just probe-time setup, which is required for supporting tagger switchover. - Now draining the CPU queues by continuously reading QS_XTR_READ, same as Ocelot, instead of one-time asserting QS_XTR_FLUSH, which actually needed a sleep to be effective. Changes in v3: Use a per-port bool is_dsa_8021q_cpu instead of a single dsa_8021q_cpu variable, to be compatible with future work where there may be potentially multiple tag_8021q CPU ports in a LAG. Changes in v2: Posted the entire rework necessary for PTP support using tag_8021q.c. Added a larger audience to the series. The Felix switch inside LS1028A has an issue. It has a 2.5G CPU port, and the external ports, in the majority of use cases, run at 1G. This means that, when the CPU injects traffic into the switch, it is very easy to run into congestion. This is not to say that it is impossible to enter congestion even with all ports running at the same speed, just that the default configuration is already very prone to that by design. Normally, the way to deal with that is using Ethernet flow control (PAUSE frames). However, this functionality is not working today with the ENETC - Felix switch pair. The hardware issue is undergoing documentation right now as an erratum within NXP, but several customers have been requesting a reasonable workaround for it. In truth, the LS1028A has 2 internal port pairs. The lack of flow control is an issue only when NPI mode (Node Processor Interface, aka the mode where the "CPU port module", which carries DSA-style tagged packets, is connected to a regular Ethernet port) is used, and NPI mode is supported by Felix on a single port. In past BSPs, we have had setups where both internal port pairs were enabled. We were advertising the following setup: "data port" "control port" (2.5G) (1G) eno2 eno3 ^ ^ | | | regular | DSA-tagged | frames | frames | | v v swp4 swp5 This works but is highly unpractical, due to NXP shifting the task of designing a functional system (choosing which port to use, depending on type of traffic required) up to the end user. The swpN interfaces would have to be bridged with swp4, in order for the eno2 "data port" to have access to the outside network. And the swpN interfaces would still be capable of IP networking. So running a DHCP client would give us two IP interfaces from the same subnet, one assigned to eno2, and the other to swpN (0, 1, 2, 3). Also, the dual port design doesn't scale. When attaching another DSA switch to a Felix port, the end result is that the "data port" cannot carry any meaningful data to the external world, since it lacks the DSA tags required to traverse the sja1105 switches below. All that traffic needs to go through the "control port". So in newer BSPs there was a desire to simplify that setup, and only have one internal port pair: eno2 eno3 ^ | | DSA-tagged x disabled | frames | v swp4 swp5 However, this setup only exacerbates the issue of not having flow control on the NPI port, since that is the only port now. Also, there are use cases that still require the "data port", such as IEEE 802.1CB (TSN stream identification doesn't work over an NPI port), source MAC address learning over NPI, etc. Again, there is a desire to keep the simplicity of the single internal port setup, while regaining the benefits of having a dedicated data port as well. And this series attempts to deliver just that. So the NPI functionality is disabled conditionally. Its purpose was: - To ensure individually addressable ports on TX. This can be replaced by using some designated VLAN tags which are pushed by the DSA tagger code, then removed by the switch (so they are invisible to the outside world and to the user). - To ensure source port identification on RX. Again, this can be replaced by using some designated VLAN tags to encapsulate all RX traffic (each VLAN uniquely identifies a source port). The DSA tagger determines which port it was based on the VLAN number, then removes that header. - To deliver PTP timestamps. This cannot be obtained through VLAN headers, so we need to take a step back and see how else we can do that. The Microchip Ocelot-1 (VSC7514 MIPS) driver performs manual injection/extraction from the CPU port module using register-based MMIO, and not over Ethernet. We will need to do the same from DSA, which makes this tagger a sort of hybrid between DSA and pure switchdev. Vladimir Oltean (10): net: dsa: tag_8021q: add helpers to deduce whether a VLAN ID is RX or TX VLAN net: mscc: ocelot: export VCAP structures to include/soc/mscc net: mscc: ocelot: store a namespaced VCAP filter ID net: mscc: ocelot: reapply bridge forwarding mask on bonding join/leave net: mscc: ocelot: don't use NPI tag prefix for the CPU port module net: dsa: document the existing switch tree notifiers and add a new one net: dsa: allow changing the tag protocol via the "tagging" device attribute net: dsa: felix: convert to the new .{set,del}_tag_protocol DSA API net: dsa: add a second tagger for Ocelot switches based on tag_8021q net: dsa: felix: perform switch setup for tag_8021q Documentation/ABI/testing/sysfs-class-net-dsa | 11 +- MAINTAINERS | 1 + drivers/net/dsa/ocelot/Kconfig | 2 + drivers/net/dsa/ocelot/felix.c | 486 ++++++++++++++++-- drivers/net/dsa/ocelot/felix.h | 2 + drivers/net/dsa/ocelot/felix_vsc9959.c | 1 + drivers/net/dsa/ocelot/seville_vsc9953.c | 1 + drivers/net/ethernet/mscc/ocelot.c | 93 ++-- drivers/net/ethernet/mscc/ocelot_flower.c | 7 +- drivers/net/ethernet/mscc/ocelot_net.c | 1 + drivers/net/ethernet/mscc/ocelot_vcap.c | 19 +- drivers/net/ethernet/mscc/ocelot_vcap.h | 295 +---------- drivers/net/ethernet/mscc/ocelot_vsc7514.c | 2 - include/linux/dsa/8021q.h | 14 + include/net/dsa.h | 23 + include/soc/mscc/ocelot.h | 6 +- include/soc/mscc/ocelot_vcap.h | 297 +++++++++++ net/dsa/Kconfig | 21 +- net/dsa/Makefile | 1 + net/dsa/dsa.c | 20 + net/dsa/dsa2.c | 129 ++++- net/dsa/dsa_priv.h | 19 + net/dsa/master.c | 26 +- net/dsa/port.c | 44 +- net/dsa/slave.c | 35 +- net/dsa/switch.c | 88 ++++ net/dsa/tag_8021q.c | 15 +- net/dsa/tag_ocelot_8021q.c | 68 +++ 28 files changed, 1306 insertions(+), 421 deletions(-) create mode 100644 net/dsa/tag_ocelot_8021q.c