mlxsw: item: Add support for local_port field in a split form

Currently, local_port field uses 8 bits, which means that maximum 256
ports can be used.

As preparation for the next ASIC, which will support more than 256
ports, local_port field should be extended to 10 bits.

It is not possible to use 10 consecutive bits in all registers, and
therefore, the field is split into 2 fields:
1. local_port - the existing 8 bits, represent LSB of the extended
field.
2. lp_msb - extra 2 bits, represent MSB of the extended field.

To avoid complex programming when reading/writing local_port, add a
dedicated macro which creates get and set functions which handle both parts
of local_port.

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@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: item: Annotate item helpers with '__maybe_unused'

mlxsw is using helpers to get / set fields in messages exchanged with
the device. It is possible that some fields are only set or only get.
This causes LLVM to emit warnings such as the following when building
with W=1 [1]:

drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c:2022:1: warning: unused function 'mlxsw_afa_sampler_mirror_agent_get'

The fact that some fields are only set or only get is very much
intentional and not indicative of functions that need to be removed.

Therefore, annotate the item helpers with '__maybe_unused' to suppress
these warnings.

[1] https://lkml.org/lkml/2021/9/29/685

Cc: Nathan Chancellor <nathan@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20211008132315.90211-1-idosch@idosch.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxsw: Replace license text with SPDX identifiers and adjust copyrights

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>

mlxsw: reg: add rdpm register

Add rdpm definition - router DSCP to priority mapping register.
This register will be utilized later to align the default mapping between
packet DSCP and switch-priority to the kernel's mapping between
packet priority and skb priority.

This is the first non-bit indexed register where the entries are arranged
in descending order, i.e., entry at offset 0 matches configuration for
dscp[63]. As a result, the item's step is converted into a signed variable
to support descending arrays [where step would be negative].

Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Signed-off-by: Nogah Frankel <nogahf@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: item: Add helpers for getting pointer into payload for char buffer item

Sometimes it is handy to get a pointer to a char buffer item and use it
direcly to write/read data. So add these helpers.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: item: Add 8bit item helpers

Item heplers for 8bit values are needed, let's add them.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: item: Make char *buf arg constant for getters

Enforce const for getter buf args.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: item: Make struct mlxsw_item args const

These should be const, so enforce it.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: item: Add MLXSW_ITEM_BUF_INDEXED helper

Add missing item helper which allows to access char bufs on multiple
offsets. This is needed by SFD and SFN register definitions.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: item: Make src arg of memcpy_to helper const

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Fix bug in __mlxsw_item_bit_array_offset

When calculating the shift needed in order to access a bit array element
in a byte, we should multiply the index by the element size and not
assume it is fixed at 2-bits.

Fixes: 93c1edb27f9e ("mlxsw: Introduce Mellanox switch driver core")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mellanox: mlxsw: Use '%zx' to print size_t format

Use '%zx' to print size_t format in order to fix the following build warning:

drivers/net/ethernet/mellanox/mlxsw/item.h:65:3: warning: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type 'size_t' [-Wformat=]

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlxsw: Introduce Mellanox switch driver core

Add core components of Mellanox switch driver infrastructure.
Core infrastructure is designed so that it can be used by multiple
bus drivers (PCI now, I2C and SGMII are planned to be implemented
in the future). Multiple switch kind drivers can be registered as well.
This core serves as a glue between buses and drivers.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Elad Raz <eladr@mellanox.com>
Reviewed-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>