1. 23 Jun, 2020 2 commits
    • Vladimir Oltean's avatar
      net: mscc: ocelot: make the NPI port a proper target for FDB and MDB · 471beb11
      Vladimir Oltean authored
      When used in DSA mode (as seen in Felix), the DEST_IDX in the MAC table
      should point to the PGID for the CPU port (PGID_CPU) and not for the
      Ethernet port where the CPU queues are redirected to (also known as Node
      Processor Interface - NPI).
      
      Because for Felix this distinction shouldn't really matter (from DSA
      perspective, the NPI port _is_ the CPU port), make the ocelot library
      act upon the CPU port when NPI mode is enabled. This has no effect for
      the mscc_ocelot driver for VSC7514, because that does not use NPI (and
      ocelot->npi is -1).
      Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      471beb11
    • Vladimir Oltean's avatar
      net: mscc: ocelot: fix encoding destination ports into multicast IPv4 address · 0897ecf7
      Vladimir Oltean authored
      The ocelot hardware designers have made some hacks to support multicast
      IPv4 and IPv6 addresses. Normally, the MAC table matches on MAC
      addresses and the destination ports are selected through the DEST_IDX
      field of the respective MAC table entry. The DEST_IDX points to a Port
      Group ID (PGID) which contains the bit mask of ports that frames should
      be forwarded to. But there aren't a lot of PGIDs (only 80 or so) and
      there are clearly many more IP multicast addresses than that, so it
      doesn't scale to use this PGID mechanism, so something else was done.
      Since the first portion of the MAC address is known, the hack they did
      was to use a single PGID for _flooding_ unknown IPv4 multicast
      (PGID_MCIPV4 == 62), but for known IP multicast, embed the destination
      ports into the first 3 bytes of the MAC address recorded in the MAC
      table.
      
      The VSC7514 datasheet explains it like this:
      
          3.9.1.5 IPv4 Multicast Entries
      
          MAC table entries with the ENTRY_TYPE = 2 settings are interpreted
          as IPv4 multicast entries.
          IPv4 multicasts entries match IPv4 frames, which are classified to
          the specified VID, and which have DMAC = 0x01005Exxxxxx, where
          xxxxxx is the lower 24 bits of the MAC address in the entry.
          Instead of a lookup in the destination mask table (PGID), the
          destination set is programmed as part of the entry MAC address. This
          is shown in the following table.
      
          Table 78: IPv4 Multicast Destination Mask
      
              Destination Ports            Record Bit Field
              ---------------------------------------------
              Ports 10-0                   MAC[34-24]
      
          Example: All IPv4 multicast frames in VLAN 12 with MAC 01005E112233 are
          to be forwarded to ports 3, 8, and 9. This is done by inserting the
          following entry in the MAC table entry:
          VALID = 1
          VID = 12
          MAC = 0x000308112233
          ENTRY_TYPE = 2
          DEST_IDX = 0
      
      But this procedure is not at all what's going on in the driver. In fact,
      the code that embeds the ports into the MAC address looks like it hasn't
      actually been tested. This patch applies the procedure described in the
      datasheet.
      
      Since there are many other fixes to be made around multicast forwarding
      until it works properly, there is no real reason for this patch to be
      backported to stable trees, or considered a real fix of something that
      should have worked.
      Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0897ecf7
  2. 22 Jun, 2020 38 commits