mlxsw: spectrum_pgt: Generalize PGT allocation

PGT blocks are allocated through the function
mlxsw_sp_pgt_mid_alloc_range(). The interface assumes that the caller knows
which piece of PGT exactly they want to get. That was fine while the FID
code was the only client allocating blocks of PGT. However for SW-allocated
LAG table, there will be an additional client: mlxsw_sp_lag_init(). The
interface should therefore be changed to not require particular
coordinates, but to take just the requested size, allocate the block
wherever, and give back the PGT address.

In this patch, change the interface accordingly. Initialize FID family's
pgt_base from the result of the PGT allocation (note that mlxsw makes a
copy of the family structure, so what gets initialized is not actually the
global structure). Drop the now-unnecessary pgt_base initializations and
the corresponding defines.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Enable unified bridge model

After all the preparations for unified bridge model, finally flip mlxsw
driver to use the new model.

Change config profile, set 'ubridge' to true and remove the configurations
that are relevant only for the legacy model. Set 'flood_mode' to
'controlled' as the current mode is not supported with unified bridge
model.

Remove all the code which is dedicated to the legacy model. Remove
'struct mlxsw_sp.ubridge' variable which was temporarily added to separate
configurations between the models.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Align PGT index to legacy bridge model

FID code reserves about 15K entries in PGT table for flooding. These
entries are just allocated and are not used yet because the code that uses
them is skipped now.

The next patches will convert MDB code to use PGT APIs. The allocation of
indexes for multicast is done after FID code reserves 15K entries.
Currently, legacy bridge model is used and firmware manages PGT table. That
means that the indexes which are allocated using PGT API are too high when
legacy bridge model is used. To not exceed firmware limitation for MDB
entries, add an API that returns the correct 'mid_index', based on bridge
model. For legacy model, subtract the number of flood entries from PGT
index. Use it to write the correct MID to SMID register. This API will be
used also from MDB code in the next patches.

PGT should not be aware of MDB and FID different usage, this API is
temporary and will be removed once unified bridge model will be used.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Extend PGT APIs to support maintaining list of ports per entry

Add an API to associate a PGT entry with SMPE index and add or remove a
port. This API will be used by FID code and MDB code, to add/remove port
from specific PGT entry.

When the first port is added to PGT entry, allocate the entry in the given
MID index, when the last port is removed from PGT entry, free it.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

mlxsw: Add an indication of SMPE index validity for PGT table

In Spectrum-1, the index into the MPE table - called switch multicast to
port egress VID (SMPE) - is derived from the PGT entry, whereas in
Spectrum-2 and later ASICs it is derived from the FID.

Therefore, in Spectrum-1, the SMPE index needs to be programmed as part of
the PGT entry via SMID register, while it is reserved for Spectrum-2 and
later ASICs.

Add 'pgt_smpe_index_valid' boolean as part of 'struct mlxsw_sp' and set
it to true for Spectrum-1 and to false for the later ASICs. Add
'smpe_index_valid' as part of 'struct mlxsw_sp_pgt' and set it according
to the value in 'struct mlxsw_sp' as part of PGT initialization.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

mlxsw: Add an initial PGT table support

The PGT (Port Group Table) table maps an index to a bitmap of local ports
to which a packet needs to be replicated. This table is used for layer 2
multicast and flooding.

In the legacy model, software did not interact with this table directly.
Instead, it was accessed by firmware in response to registers such as
SFTR and SMID. In the new model, the SFTR register is deprecated and
software has full control over the PGT table using the SMID register.

The entire state of the PGT table needs to be maintained in software
because member ports in a PGT entry needs to be reference counted to avoid
releasing entries which are still in use.

Add the following APIs:
1. mlxsw_sp_pgt_{init, fini}() - allocate/free the PGT table.
2. mlxsw_sp_pgt_mid_alloc_range() - allocate a range of MID indexes in PGT.
To be used by FID code during initialization to reserve specific PGT
indexes for flooding entries.
3. mlxsw_sp_pgt_mid_free_range() - free indexes in a given range.
4. mlxsw_sp_pgt_mid_alloc() - allocate one MID index in the PGT at a
non-specific range, just search for free index. To be used by MDB code.
5. mlxsw_sp_pgt_mid_free() - free the given index.

Note that alloc() functions do not allocate the entries in software, just
allocate IDs using 'idr'.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>