net: marvell: prestera: Add length macros for prestera_ip_addr

Add macros to determine IP address length (internal driver types).
This will be used in next patches for nexthops logic.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Add router nexthops ABI

- Add functions to allocate/delete/set nexthop group
- NOTE: non-ECMP nexthop is nexthop group with allocated size = 1
- Add function to read state of HW nh (if packets going through it)

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: add hardware router objects accounting for lpm

Add new router_hw object "fib_node". For now it support only DROP and
TRAP mode.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: marvell: prestera: Fix deinit sequence for router

* Add missed call prestera_router_fini in prestera_switch_fini
* Add prestera_router_hw_fini, which verify lists are empty

Fixes: 69204174cc5c ("net: marvell: prestera: Add prestera router infra")
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Link: https://lore.kernel.org/r/20220111011129.5457-1-yevhen.orlov@plvision.eu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Refactor get/put VR functions

* Use refcount, instead of uint
* Increment/decrement recount inside get/put
* Fix error path in __prestera_vr_create. Remove unnecessary kfree.
* Make __prestera_vr_destroy symmetric to "create"

Fixes: bca5859bc6c6 ("net: marvell: prestera: add hardware router objects accounting")
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Link: https://lore.kernel.org/r/20220111011014.4418-1-yevhen.orlov@plvision.eu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: add hardware router objects accounting

Add prestera_router_hw.c. This file contains functions, which track HW
objects relations and links. This include implicity creation of objects,
that needed by requested one and implicity removing of objects, which
reference counter is became zero.

We need this layer, because kernel callbacks not always mapped to
creation of single HW object. So let it be two different layers - one
for subscribing and parsing kernel structures, and another
(prestera_router_hw.c) for HW objects relations tracking.

There is two types of objects on router_hw layer:
- Explicit objects (rif_entry) : created by higher layer.
- Implicit objects (vr) : created on demand by explicit objects.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>