linux-dev/drivers/net/dsa/ocelot, branch linus/master

net: dsa: felix: tag_8021q preparation for multiple CPU ports

2022-05-23T09:39:55Z

Update the VCAP filters to support multiple tag_8021q CPU ports. TX works using a filter for VLAN ID on the ingress of the CPU port, with a redirect and a VLAN pop action. This can be updated trivially by amending the ingress port mask of this rule to match on all tag_8021q CPU ports. RX works using a filter for ingress port on the egress of the CPU port, with a VLAN push action. Here we need to replicate these filters for each tag_8021q CPU port, and let them all have the same action. This means that the OCELOT_VCAP_ES0_TAG_8021Q_RXVLAN() cookie needs to encode a unique value for every {user port, CPU port} pair it's given. Do this by encoding the CPU port in the upper 16 bits of the cookie, and the user port in the lower 16 bits. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller

net: mscc: ocelot: switch from {,un}set to {,un}assign for tag_8021q CPU ports

2022-05-23T09:39:54Z

There is a desire for the felix driver to gain support for multiple tag_8021q CPU ports, but the current model prevents it. This is because ocelot_apply_bridge_fwd_mask() only takes into consideration whether a port is a tag_8021q CPU port, but not whose CPU port it is. We need a model where we can have a direct affinity between an ocelot port and a tag_8021q CPU port. This serves as the basis for multiple CPU ports. Declare a "dsa_8021q_cpu" backpointer in struct ocelot_port which encodes that affinity. Repurpose the "ocelot_set_dsa_8021q_cpu" API to "ocelot_assign_dsa_8021q_cpu" to express the change of paradigm. Note that this change makes the first practical use of the new ocelot_port->index field in ocelot_port_unassign_dsa_8021q_cpu(), where we need to remove the old tag_8021q CPU port from the reserved VLAN range. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller

net: dsa: felix: directly call ocelot_port_{set,unset}_dsa_8021q_cpu

2022-05-23T09:39:54Z

Absorb the final details of calling ocelot_port_{,un}set_dsa_8021q_cpu(), i.e. the need to lock &ocelot->fwd_domain_lock, into the callee, to simplify the caller and permit easier code reuse later. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller

net: dsa: felix: update bridge fwd mask from ocelot lib when changing tag_8021q CPU

2022-05-23T09:39:54Z

Add more logic to ocelot_port_{,un}set_dsa_8021q_cpu() from the ocelot switch lib by encapsulating the ocelot_apply_bridge_fwd_mask() call that felix used to have. This is necessary because the CPU port change procedure will also need to do this, and it's good to reduce code duplication by having an entry point in the ocelot switch lib that does all that is needed. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller

net: dsa: felix: move the updating of PGID_CPU to the ocelot lib

2022-05-23T09:39:54Z

PGID_CPU must be updated every time a port is configured or unconfigured as a tag_8021q CPU port. The ocelot switch lib already has a hook for that operation, so move the updating of PGID_CPU to those hooks. These bits are pretty specific to DSA, so normally I would keep them out of the common switch lib, but when tag_8021q is in use, this has implications upon the forwarding mask determined by ocelot_apply_bridge_fwd_mask() and called extensively by the switch lib. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller

net: dsa: fix missing adjustment of host broadcast flooding

2022-05-23T09:39:54Z

PGID_BC is configured statically by ocelot_init() to flood towards the CPU port module, and dynamically by ocelot_port_set_bcast_flood() towards all user ports. When the tagging protocol changes, the intention is to turn off flooding towards the old pipe towards the host, and to turn it on towards the new pipe. Due to a recent change which removed the adjustment of PGID_BC from felix_set_host_flood(), 3 things happen. - when we change from NPI to tag_8021q mode: in this mode, the CPU port module is accessed via registers, and used to read PTP packets with timestamps. We fail to disable broadcast flooding towards the CPU port module, and to enable broadcast flooding towards the physical port that serves as a DSA tag_8021q CPU port. - from tag_8021q to NPI mode: in this mode, the CPU port module is redirected to a physical port. We fail to disable broadcast flooding towards the physical tag_8021q CPU port, and to enable it towards the CPU port module at ocelot->num_phys_ports. - when the ports are put in promiscuous mode, we also fail to update PGID_BC towards the host pipe of the current protocol. First issue means that felix_check_xtr_pkt() has to do extra work, because it will not see only PTP packets, but also broadcasts. It needs to dequeue these packets just to drop them. Third issue is inconsequential, since PGID_BC is allocated from the nonreserved multicast PGID space, and these PGIDs are conveniently initialized to 0x7f (i.e. flood towards all ports except the CPU port module). Broadcasts reach the NPI port via ocelot_init(), and reach the tag_8021q CPU port via the hardware defaults. Second issue is also inconsequential, because we fail both at disabling and at enabling broadcast flooding on a port, so the defaults mentioned above are preserved, and they are fine except for the performance impact. Fixes: 7a29d220f4c0 ("net: dsa: felix: reimplement tagging protocol change with function pointers") Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller

net: mscc: ocelot: move ocelot_port_private :: chip_port to ocelot_port :: index

2022-05-12T23:39:18Z

Currently the ocelot switch lib is unaware of the index of a struct ocelot_port, since that is kept in the encapsulating structures of outer drivers (struct dsa_port :: index, struct ocelot_port_private :: chip_port). With the upcoming increase in complexity associated with assigning DSA tag_8021q CPU ports to certain user ports, it becomes necessary for the switch lib to be able to retrieve the index of a certain ocelot_port. Therefore, introduce a new u8 to ocelot_port (same size as the chip_port used by the ocelot switchdev driver) and rework the existing code to populate and use it. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski

net: dsa: felix: reimplement tagging protocol change with function pointers

2022-05-12T23:38:55Z

The error handling for the current tagging protocol change procedure is a bit brittle (we dismantle the previous tagging protocol entirely before setting up the new one). By identifying which parts of a tagging protocol are unique to itself and which parts are shared with the other, we can implement a protocol change procedure where error handling is a bit more robust, because we start setting up the new protocol first, and tear down the old one only after the setup of the specific and shared parts succeeded. The protocol change is a bit too open-coded too, in the area of migrating host flood settings and MDBs. By identifying what differs between tagging protocols (the forwarding masks for host flooding) we can implement a more straightforward migration procedure which is handled in the shared portion of the protocol change, rather than individually by each protocol. Therefore, a more structured approach calls for the introduction of a structure of function pointers per tagging protocol. This covers setup, teardown and the host forwarding mask. In the future it will also cover how to prepare for a new DSA master. The initial tagging protocol setup (at driver probe time) and the final teardown (at driver removal time) are also adapted to call into the structured methods of the specific protocol in current use. This is especially relevant for teardown, where we previously called felix_del_tag_protocol() only for the first CPU port. But by not specifying which CPU port this is for, we gain more flexibility to support multiple CPU ports in the future. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski

net: dsa: felix: dynamically determine tag_8021q CPU port for traps

2022-05-12T23:38:55Z

Ocelot switches support a single active CPU port at a time (at least as a trapping destination, i.e. for control traffic). This is true regardless of whether we are using the native copy-to-CPU-port-module functionality, or a redirect action towards the software-defined tag_8021q CPU port. Currently we assume that the trapping destination in tag_8021q mode is the first CPU port, yet in the future we may want to migrate the user ports to the second CPU port. For that to work, we need to make sure that the tag_8021q trapping destination is a CPU port that is active, i.e. is used by at least some user port on which the trap was added. Otherwise, we may end up redirecting the traffic to a CPU port which isn't even up. Note that due to the current design where we simply choose the CPU port of the first port from the trap's ingress port mask, it may be that a CPU port absorbes control traffic from user ports which aren't affine to it as per user space's request. This isn't ideal, but is the lesser of two evils. Following the user-configured affinity for traps would mean that we can no longer reuse a single TCAM entry for multiple traps, which is what we actually do for e.g. PTP. Either we duplicate and deduplicate TCAM entries on the fly when user-to-CPU-port mappings change (which is unnecessarily complicated), or we redirect trapped traffic to all tag_8021q CPU ports if multiple such ports are in use. The latter would have actually been nice, if it actually worked, but it doesn't, since a OCELOT_MASK_MODE_REDIRECT action towards multiple ports would not take PGID_SRC into consideration, and it would just duplicate the packet towards each (CPU) port, leading to duplicates in software. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski

net: dsa: remove port argument from ->change_tag_protocol()

2022-05-12T23:38:55Z

DSA has not supported (and probably will not support in the future either) independent tagging protocols per CPU port. Different switch drivers have different requirements, some may need to replicate some settings for each CPU port, some may need to apply some settings on a single CPU port, while some may have to configure some global settings and then some per-CPU-port settings. In any case, the current model where DSA calls ->change_tag_protocol for each CPU port turns out to be impractical for drivers where there are global things to be done. For example, felix calls dsa_tag_8021q_register(), which makes no sense per CPU port, so it suppresses the second call. Let drivers deal with replication towards all CPU ports, and remove the CPU port argument from the function prototype. Signed-off-by: Vladimir Oltean Acked-by: Luiz Angelo Daros de Luca Signed-off-by: Jakub Kicinski