Merge branch 'net-ti-storm-prevention-support'

Merge branch 'net-ti-storm-prevention-support'

Grygorii Strashko says:

====================
net: ethernet: ti: enable bc/mc storm prevention support

This series first adds supports for the ALE feature to rate limit number ingress
broadcast(BC)/multicast(MC) packets per/sec which main purpose is BC/MC storm
prevention.

And then enables corresponding support for ingress broadcast(BC)/multicast(MC)
packets rate limiting for TI CPSW switchdev and AM65x/J221E CPSW_NUSS drivers by
implementing HW offload for simple tc-flower with policer action with matches
on dst_mac/mask:
 - ff:ff:ff:ff:ff:ff/ff:ff:ff:ff:ff:ff has to be used for BC packets rate
limiting (exact match)
 - 01:00:00:00:00:00/01:00:00:00:00:00 fixed value has to be used for MC
packets rate limiting

The CPSW supports MC/BC packets rate limiting in packets/sec and affects
all ingress MC/BC packets and serves as BC/MC storm prevention feature.

Examples:
- BC rate limit to 1000pps:
  tc qdisc add dev eth0 clsact
  tc filter add dev eth0 ingress flower skip_sw dst_mac ff:ff:ff:ff:ff:ff \
  action police pkts_rate 1000 pkts_burst 1 drop

- MC rate limit to 20000pps:
  tc qdisc add dev eth0 clsact
  tc filter add dev eth0 ingress flower skip_sw dst_mac 01:00:00:00:00:00/01:00:00:00:00:00 \
  action police rate pkts_rate 20000 pkts_burst 1 drop

  pkts_burst - not used.

The solution inspired patch from Vladimir Oltean [1].

Changes in v3:
  - comments applied
  - policer validation added

Changes in v2:
 - switch to packet-per-second policing introduced by
   commit 2ffe0395288a ("net/sched: act_police: add support for packet-per-second policing") [2]

v2: https://patchwork.kernel.org/project/netdevbpf/cover/20211101170122.19160-1-grygorii.strashko@ti.com/
v1: https://patchwork.kernel.org/project/netdevbpf/cover/20201114035654.32658-1-grygorii.strashko@ti.com/

[1] https://lore.kernel.org/patchwork/patch/1217254/
[2] https://patchwork.kernel.org/project/netdevbpf/cover/20210312140831.23346-1-simon.horman@netronome.com/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>