net: mscc: ocelot: support IPv4, IPv6 and plain Ethernet mdb entries
The current procedure for installing a multicast address is hardcoded for IPv4. But, in the ocelot hardware, there are 3 different procedures for IPv4, IPv6 and for regular L2 multicast. For IPv6 (33-33-xx-xx-xx-xx), it's the same as for IPv4 (01-00-5e-xx-xx-xx), except that the destination port mask is stuffed into first 2 bytes of the MAC address except into first 3 bytes. For plain Ethernet multicast, there's no port-in-address stuffing going on, instead the DEST_IDX (pointer to PGID) is used there, just as for unicast. So we have to use one of the nonreserved multicast PGIDs that the hardware has allocated for this purpose. This patch classifies the type of multicast address based on its first bytes, then redirects to one of the 3 different hardware procedures. Note that this gives us a really better way of redirecting PTP frames sent at 01-1b-19-00-00-00 to the CPU. Previously, Yangbo Lu tried to add a trapping rule for PTP EtherType but got a lot of pushback: https://patchwork.ozlabs.org/project/netdev/patch/20190813025214.18601-5-yangbo.lu@nxp.com/ But right now, that isn't needed at all. The application stack (ptp4l) does this for the PTP multicast addresses it's interested in (which are configurable, and include 01-1b-19-00-00-00): memset(&mreq, 0, sizeof(mreq)); mreq.mr_ifindex = index; mreq.mr_type = PACKET_MR_MULTICAST; mreq.mr_alen = MAC_LEN; memcpy(mreq.mr_address, addr1, MAC_LEN); err1 = setsockopt(fd, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq, sizeof(mreq)); Into the kernel, this translates into a dev_mc_add on the switch network interfaces, and our drivers know that it means they should translate it into a host MDB address (make the CPU port be the destination). Previously, this was broken because all mdb addresses were treated as IPv4 (which 01-1b-19-00-00-00 obviously is not). Signed-off-by:Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
parent
96b029b0
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