mlxsw: Add Spectrum-1 ip6gre support

Ido Schimmel writes:

Currently, mlxsw only supports ip6gre offload on Spectrum-2 and newer ASICs. Spectrum-1 can also offload ip6gre tunnels, but it needs double entry router interfaces (RIFs) for the RIFs representing these tunnels. In addition, the RIF index needs to be even. This is handled in patches #1-#3.

The implementation can otherwise be shared between all Spectrum generations. This is handled in patches #4-#5.

Patch #6 moves a mlxsw ip6gre selftest to a shared directory, as ip6gre is no longer only supported on Spectrum-2 and newer ASICs.

This work is motivated by users that require multiple GRE tunnels that all share the same underlay VRF. Currently, mlxsw only supports decapsulation based on the underlay destination IP (i.e., not taking the GRE key into account), so users need to configure these tunnels with different source IPs and IPv6 addresses are easier to spare than IPv4.

Tested using existing ip6gre forwarding selftests.

Ido Schimmel (6):
mlxsw: spectrum_router: Use gen_pool for RIF index allocation
mlxsw: spectrum_router: Parametrize RIF allocation size
mlxsw: spectrum_router: Add support for double entry RIFs
mlxsw: spectrum_ipip: Rename Spectrum-2 ip6gre operations
mlxsw: spectrum_ipip: Add Spectrum-1 ip6gre support
selftests: mlxsw: Move IPv6 decap_error test to shared directory

 .../ethernet/mellanox/mlxsw/spectrum_ipip.c   | 160 +++++-------------
 .../ethernet/mellanox/mlxsw/spectrum_ipip.h   |   1 +
 .../ethernet/mellanox/mlxsw/spectrum_router.c | 102 +++++++++--
 .../ethernet/mellanox/mlxsw/spectrum_router.h |   4 +
 .../devlink_trap_tunnel_ipip6.sh              |   2 +-
 5 files changed, 138 insertions(+), 131 deletions(-)
 rename tools/testing/selftests/drivers/net/mlxsw/{spectrum-2 => }/devlink_trap_tunnel_ipip6.sh (99%)

2.35.3