bridge: mrp: Extend br_mrp_switchdev to detect better the errors

This patch extends the br_mrp_switchdev functions to be able to have a
better understanding what cause the issue and if the SW needs to be used
as a backup.

There are the following cases:
- when the code is compiled without CONFIG_NET_SWITCHDEV. In this case
return success so the SW can continue with the protocol. Depending
on the function, it returns 0 or BR_MRP_SW.
- when code is compiled with CONFIG_NET_SWITCHDEV and the driver doesn't
implement any MRP callbacks. In this case the HW can't run MRP so it
just returns -EOPNOTSUPP. So the SW will stop further to configure the
node.
- when code is compiled with CONFIG_NET_SWITCHDEV and the driver fully
supports any MRP functionality. In this case the SW doesn't need to do
anything. The functions will return 0 or BR_MRP_HW.
- when code is compiled with CONFIG_NET_SWITCHDEV and the HW can't run
completely the protocol but it can help the SW to run it. For
example, the HW can't support completely MRM role(can't detect when it
stops receiving MRP Test frames) but it can redirect these frames to
CPU. In this case it is possible to have a SW fallback. The SW will
try initially to call the driver with sw_backup set to false, meaning
that the HW should implement completely the role. If the driver returns
-EOPNOTSUPP, the SW will try again with sw_backup set to false,
meaning that the SW will detect when it stops receiving the frames but
it needs HW support to redirect the frames to CPU. In case the driver
returns 0 then the SW will continue to configure the node accordingly.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: bridge: propagate extack through switchdev_port_attr_set

The benefit is the ability to propagate errors from switchdev drivers
for the SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING and
SWITCHDEV_ATTR_ID_BRIDGE_VLAN_PROTOCOL attributes.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bridge: mrp: Fix the usage of br_mrp_port_switchdev_set_state

The function br_mrp_port_switchdev_set_state was called both with MRP
port state and STP port state, which is an issue because they don't
match exactly.

Therefore, update the function to be used only with STP port state and
use the id SWITCHDEV_ATTR_ID_PORT_STP_STATE.

The choice of using STP over MRP is that the drivers already implement
SWITCHDEV_ATTR_ID_PORT_STP_STATE and already in SW we update the port
STP state.

Fixes: 9a9f26e8f7ea30 ("bridge: mrp: Connect MRP API with the switchdev API")
Fixes: fadd409136f0f2 ("bridge: switchdev: mrp: Implement MRP API for switchdev")
Fixes: 2f1a11ae11d222 ("bridge: mrp: Add MRP interface.")
Reported-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bridge: switchdev: mrp: Extend MRP API for switchdev for MRP Interconnect

Implement the MRP API for interconnect switchdev. Similar with the other
br_mrp_switchdev function, these function will just eventually call the
switchdev functions: switchdev_port_obj_add/del.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bridge: mrp: Add support for role MRA

A node that has the MRA role, it can behave as MRM or MRC.

Initially it starts as MRM and sends MRP_Test frames on both ring ports.
If it detects that there are MRP_Test send by another MRM, then it
checks if these frames have a lower priority than itself. In this case
it would send MRP_Nack frames to notify the other node that it needs to
stop sending MRP_Test frames.
If it receives a MRP_Nack frame then it stops sending MRP_Test frames
and starts to behave as a MRC but it would continue to monitor the
MRP_Test frames send by MRM. If at a point the MRM stops to send
MRP_Test frames it would get the MRM role and start to send MRP_Test
frames.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bridge: mrp: Set the priority of MRP instance

Each MRP instance has a priority, a lower value means a higher priority.
The priority of MRP instance is stored in MRP_Test frame in this way
all the MRP nodes in the ring can see other nodes priority.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bridge: switchdev: mrp: Implement MRP API for switchdev

Implement the MRP api for switchdev.
These functions will just eventually call the switchdev functions:
switchdev_port_obj_add/del and switchdev_port_attr_set.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>