RFC Add ETS and TBF Qdisc offload for Airoha EN7581 SoC

Introduce support for ETS and TBF qdisc offload available in the Airoha EN7581 ethernet controller.
Some DSA hw switches do not support Qdisc offloading or the mac chip has more fine grained QoS capabilities with respect to the hw switch (e.g. Airoha EN7581 mac chip has more hw QoS and buffering capabilities with respect to the mt7530 switch).
Introduce ndo_setup_tc_conduit callback in order to allow tc to offload Qdisc policies for the specified DSA user port configuring the hw switch cpu port (mac chip).

Lorenzo Bianconi (5):
net: airoha: Enable Tx drop capability for each Tx DMA ring
net: airoha: Introduce ndo_select_queue callback
net: dsa: Introduce ndo_setup_tc_conduit callback
net: airoha: Add sched ETS offload support
net: airoha: Add sched TBF offload support

 drivers/net/ethernet/mediatek/airoha_eth.c | 372 ++++++++++++++++++++-
 include/linux/netdevice.h                  |  12 +
 net/dsa/user.c                             |  47 ++-
 3 files changed, 422 insertions(+), 9 deletions(-)

2.47.1