Each TCAM region currently uses its own resources and there is no
sharing between the different regions.
This is going to change with A-TCAM as each region will need to allocate
an eRP table from the global eRP tables array.
Make the global TCAM resources available to each region by passing the
TCAM private data to the region initialization routine.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In Spectrum-2 the C-TCAM is only used for rules that can't fit in the
A-TCAM due to a limited number of masks per A-TCAM region.
In addition, rules inserted into the C-TCAM may affect rules residing in
the A-TCAM, by clearing their C-TCAM prune bit.
The two regions are thus closely related and can be thought of as if the
C-TCAM region is encapsulated in the A-TCAM one.
Change the data structures to reflect that before introducing A-TCAM
support and make C-TCAM region initialization part of the A-TCAM region
initialization sequence.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initialize the A-TCAM as part of the driver's initialization routine.
Specifically, initialize the eRP tables so that A-TCAM regions will be
able to perform allocations of eRP tables upon rule insertion in
subsequent patches.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The number of eRPs that can be used by a single A-TCAM region is limited
to 16. When more eRPs are needed, an ordinary circuit TCAM (C-TCAM) can
be used to hold the extra eRPs.
Unlike the A-TCAM, only a single (last) lookup is performed in the
C-TCAM and not a lookup per-eRP. However, modeling the C-TCAM as extra
eRPs will allow us to easily introduce support for pruning in a
follow-up patch set and is also logically correct.
The following diagram depicts the relation between both TCAMs:
C-TCAM
+-------------------+ +--------------------+ +-----------+
| | | | | |
| eRP #1 (A-TCAM) +----> ... +----+ eRP #16 (A-TCAM) +----+ eRP #17 |
| | | | | ... |
+-------------------+ +--------------------+ | eRP #N |
| |
+-----------+
Lookup order is from left to right.
Extend the eRP core APIs with a C-TCAM parameter which indicates whether
the requested eRP is to be used with the C-TCAM or not.
Since the C-TCAM is only meant to absorb rules that can't fit in the
A-TCAM due to exceeded number of eRPs or key collision, an error is
returned when a C-TCAM eRP needs to be created when the eRP state
machine is in its initial state (i.e., 'no masks'). This should only
happen in the face of very unlikely errors when trying to push rules
into the A-TCAM.
In order not to perform unnecessary lookups, the eRP core will only
enable a C-TCAM lookup for a given region if it knows there are C-TCAM
eRPs present.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When rules are inserted into the A-TCAM they are associated with a mask,
which is part of the lookup key: { masked key, mask ID, region ID }.
These masks are called rule patterns (RP) and the aggregation of several
masks into one (to be introduced in follow-up patch sets) is called an
extended RP (eRP).
When a packet undergoes a lookup in an ACL region it is masked by the
current set of eRPs used by the region, looking for an exact match.
Eventually, the rule with the highest priority is picked.
These eRPs are stored in several global banks to allow for lookup to
occur using several eRPs simultaneously.
At first, an ACL region will only require a single mask - upon the
insertion of the first rule. In this case, the region can use the
"master RP" which is composed by OR-ing all the masks used by the
region. This mask is a property of the region and thus there is no need
to use the above mentioned banks.
At some point, a second mask will be needed. In this case, the region
will need to allocate an eRP table from the above mentioned banks and
insert its masks there.
>From now on, upon lookup, the eRP table used by the region will be
fetched from the eRP banks - using {eRP bank, Index within the bank} -
and the eRPs present in the table will be used to mask the packet. Note
that masks with consecutive indexes are inserted into consecutive banks.
When rules are deleted and a region only needs a single mask once again
it can free its eRP table and use the master RP.
The above logic is implemented in the eRP core and represented using the
following state machine:
+------------+ create mask - as master RP +---------------+
| +--------------------------------> |
| no masks | | single mask |
| <--------------------------------+ |
+------------+ delete mask +-----+--^------+
| |
| |
create mask - | | delete mask -
create mask transition to use eRP | | transition to
+--------+ table | | use master RP
| | | |
| | | |
+----v--------+----+ create mask +----v--+-----+
| <-------------------------------+ |
| multiple masks | | two masks |
| +-------------------------------> |
+------------------+ delete mask - if two +-------------+
remaining
The code that actually configures rules in the A-TCAM will interface
with the eRP core by getting or putting an eRP based on the required
mask used by the rule.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since cld_flower provides information about the filter template for
specific chain, use this information in order to prepare a region.
Use the template to find out what elements are going to be used
and pass that down to mlxsw_sp_acl_tcam_group_add(). Later on, when the
first filter is inserted, the mlxsw_sp_acl_tcam_group_use_patterns()
function would use this element usage information instead of looking
up a pattern.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Utilize only C-TCAM for now. Do very minimal A-TCAM initialization in
order to make C-TCAM work.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For Spectrum-2, we need to insert priority to C-TCAM because HW
needs that info in order to correctly process scenarios where rules
are in both C-TCAM and A-TCAM.
So extend the mlxsw_sp_acl_ctcam_entry_add() args to accept indication
if priority needs to be filled up and implement the priority
computation and fill-up.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add ops to be called on driver instance init and fini.
This is needed in order to be possible to do Spectrum-2 specific init
and fini work.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To allow easy and clean Spectrum-2 implementation for things that differ
from Spectrum, split the existing ACL TCAM code 3 ways:
1) common code that calls Spectrum/Spectrum-2 specific ops
2) Spectrum ops implementations
3) common C-TCAM code that is going to be shared between Spectrum and
Spectrum-2 implementations
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ido Schimmel