[net-next,v2,0/5] net: xilinx: axienet: Multicast fixes and improvements

Message

Sean Anderson Aug. 15, 2024, 7:36 p.m. UTC

This series has a few small patches improving the handling of multicast
addresses. In particular, it makes the driver a whole lot less spammy,
and adjusts things so we aren't in promiscuous mode when we have more
than four multicast addresses (a common occurance on modern systems).

As the hardware has a 4-entry CAM, the ideal method would be to "pack"
multiple addresses into one CAM entry. Something like:

entry.address = address[0] | address[1];
entry.mask = ~(address[0] ^ address[1]);

Which would make the entry match both addresses (along with some others
that would need to be filtered in software).

Mapping addresses to entries in an efficient way is a bit tricky. If
anyone knows of an in-tree example of something like this, I'd be glad
to hear about it.

Changes in v2:
- Split off IFF_PROMISC change from printing changes

Sean Anderson (5):
  net: xilinx: axienet: Always disable promiscuous mode
  net: xilinx: axienet: Fix dangling multicast addresses
  net: xilinx: axienet: Don't print if we go into promiscuous mode
  net: xilinx: axienet: Don't set IFF_PROMISC in ndev->flags
  net: xilinx: axienet: Support IFF_ALLMULTI

 drivers/net/ethernet/xilinx/xilinx_axienet.h  |  3 ++
 .../net/ethernet/xilinx/xilinx_axienet_main.c | 52 +++++++++----------
 2 files changed, 29 insertions(+), 26 deletions(-)