Setting DSA_MAX_PORTS caused DSA to call b53 callbacks (e.g.
b53_disable_port() during dsa_register_switch()) for invalid
(non-existent) ports. That made b53 modify unrelated registers and is
one of reasons for a broken BCM5301x support.

This problem exists for years but DSA_MAX_PORTS usage has changed few
times. It seems the most accurate to reference commit dropping
dsa_switch_alloc() in the Fixes tag.

Fixes: 7e99e347 ("net: dsa: remove dsa_switch_alloc helper")
Signed-off-by: NRafał Miłecki <rafal@milecki.pl>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It isn't true that CPU port is always the last one. Switches BCM5301x
have 9 ports (port 6 being inactive) and they use port 5 as CPU by
default (depending on design some other may be CPU ports too).

A more reliable way of determining number of ports is to check for the
last set bit in the "enabled_ports" bitfield.

This fixes b53 internal state, it will allow providing accurate info to
the DSA and is required to fix BCM5301x support.

Fixes: 967dd82f ("net: dsa: b53: Add support for Broadcom RoboSwitch")
Signed-off-by: NRafał Miłecki <rafal@milecki.pl>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, outgoing packets larger than 1496 bytes are dropped when
tagged VLAN is used on a switch port.

Add the frame check sequence length to the value of the register
GSWIP_MAC_FLEN to fix this. This matches the lantiq_ppa vendor driver,
which uses a value consisting of 1518 bytes for the MAC frame, plus the
lengths of special tag and VLAN tags.

Fixes: 14fceff4 ("net: dsa: Add Lantiq / Intel DSA driver for vrx200")
Cc: stable@vger.kernel.org
Signed-off-by: NJan Hoffmann <jan@3e8.eu>
Acked-by: NHauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Traffic schedules can only be started up to eight seconds within the
future. Therefore, the driver periodically checks every two seconds whether the
admin base time provided by the user is inside that window. If so the schedule
is started. Otherwise the check is deferred.

However, according to the programming manual the look ahead window size should
be four - not eight - seconds. By using the proposed value of four seconds
starting a schedule at a specified admin base time actually works as expected.

Fixes: 24dfc6eb ("net: dsa: hellcreek: Add TAPRIO offloading support")
Signed-off-by: NKurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the gate control list which is programmed into the hardware is
incorrect resulting in wrong traffic schedules. The problem is the loop
variables are incremented before they are referenced. Therefore, move the
increment to the end of the loop.

Fixes: 24dfc6eb ("net: dsa: hellcreek: Add TAPRIO offloading support")
Signed-off-by: NKurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduced in commit 38b5beea ("net: dsa: sja1105: prepare tagger
for handling DSA tags and VLAN simultaneously"), the sja1105_xmit_tpid
function solved quite a different problem than our needs are now.

Then, we used best-effort VLAN filtering and we were using the xmit_tpid
to tunnel packets coming from an 8021q upper through the TX VLAN allocated
by tag_8021q to that egress port. The need for a different VLAN protocol
depending on switch revision came from the fact that this in itself was
more of a hack to trick the hardware into accepting tunneled VLANs in
the first place.

Right now, we deny 8021q uppers (see sja1105_prechangeupper). Even if we
supported them again, we would not do that using the same method of
{tunneling the VLAN on egress, retagging the VLAN on ingress} that we
had in the best-effort VLAN filtering mode. It seems rather simpler that
we just allocate a VLAN in the VLAN table that is simply not used by the
bridge at all, or by any other port.

Anyway, I have 2 gripes with the current sja1105_xmit_tpid:

1. When sending packets on behalf of a VLAN-aware bridge (with the new
   TX forwarding offload framework) plus untagged (with the tag_8021q
   VLAN added by the tagger) packets, we can see that on SJA1105P/Q/R/S
   and later (which have a qinq_tpid of ETH_P_8021AD), some packets sent
   through the DSA master have a VLAN protocol of 0x8100 and others of
   0x88a8. This is strange and there is no reason for it now. If we have
   a bridge and are therefore forced to send using that bridge's TPID,
   we can as well blend with that bridge's VLAN protocol for all packets.

2. The sja1105_xmit_tpid introduces a dependency on the sja1105 driver,
   because it looks inside dp->priv. It is desirable to keep as much
   separation between taggers and switch drivers as possible. Now it
   doesn't do that anymore.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sja1105 driver is a bit special in its use of VLAN headers as DSA
tags. This is because in VLAN-aware mode, the VLAN headers use an actual
TPID of 0x8100, which is understood even by the DSA master as an actual
VLAN header.

Furthermore, control packets such as PTP and STP are transmitted with no
VLAN header as a DSA tag, because, depending on switch generation, there
are ways to steer these control packets towards a precise egress port
other than VLAN tags. Transmitting control packets as untagged means
leaving a door open for traffic in general to be transmitted as untagged
from the DSA master, and for it to traverse the switch and exit a random
switch port according to the FDB lookup.

This behavior is a bit out of line with other DSA drivers which have
native support for DSA tagging. There, it is to be expected that the
switch only accepts DSA-tagged packets on its CPU port, dropping
everything that does not match this pattern.

We perhaps rely a bit too much on the switches' hardware dropping on the
CPU port, and place no other restrictions in the kernel data path to
avoid that. For example, sja1105 is also a bit special in that STP/PTP
packets are transmitted using "management routes"
(sja1105_port_deferred_xmit): when sending a link-local packet from the
CPU, we must first write a SPI message to the switch to tell it to
expect a packet towards multicast MAC DA 01-80-c2-00-00-0e, and to route
it towards port 3 when it gets it. This entry expires as soon as it
matches a packet received by the switch, and it needs to be reinstalled
for the next packet etc. All in all quite a ghetto mechanism, but it is
all that the sja1105 switches offer for injecting a control packet.
The driver takes a mutex for serializing control packets and making the
pairs of SPI writes of a management route and its associated skb atomic,
but to be honest, a mutex is only relevant as long as all parties agree
to take it. With the DSA design, it is possible to open an AF_PACKET
socket on the DSA master net device, and blast packets towards
01-80-c2-00-00-0e, and whatever locking the DSA switch driver might use,
it all goes kaput because management routes installed by the driver will
match skbs sent by the DSA master, and not skbs generated by the driver
itself. So they will end up being routed on the wrong port.

So through the lens of that, maybe it would make sense to avoid that
from happening by doing something in the network stack, like: introduce
a new bit in struct sk_buff, like xmit_from_dsa. Then, somewhere around
dev_hard_start_xmit(), introduce the following check:

	if (netdev_uses_dsa(dev) && !skb->xmit_from_dsa)
		kfree_skb(skb);

Ok, maybe that is a bit drastic, but that would at least prevent a bunch
of problems. For example, right now, even though the majority of DSA
switches drop packets without DSA tags sent by the DSA master (and
therefore the majority of garbage that user space daemons like avahi and
udhcpcd and friends create), it is still conceivable that an aggressive
user space program can open an AF_PACKET socket and inject a spoofed DSA
tag directly on the DSA master. We have no protection against that; the
packet will be understood by the switch and be routed wherever user
space says. Furthermore: there are some DSA switches where we even have
register access over Ethernet, using DSA tags. So even user space
drivers are possible in this way. This is a huge hole.

However, the biggest thing that bothers me is that udhcpcd attempts to
ask for an IP address on all interfaces by default, and with sja1105, it
will attempt to get a valid IP address on both the DSA master as well as
on sja1105 switch ports themselves. So with IP addresses in the same
subnet on multiple interfaces, the routing table will be messed up and
the system will be unusable for traffic until it is configured manually
to not ask for an IP address on the DSA master itself.

It turns out that it is possible to avoid that in the sja1105 driver, at
least very superficially, by requesting the switch to drop VLAN-untagged
packets on the CPU port. With the exception of control packets, all
traffic originated from tag_sja1105.c is already VLAN-tagged, so only
STP and PTP packets need to be converted. For that, we need to uphold
the equivalence between an untagged and a pvid-tagged packet, and to
remember that the CPU port of sja1105 uses a pvid of 4095.

Now that we drop untagged traffic on the CPU port, non-aggressive user
space applications like udhcpcd stop bothering us, and sja1105 effectively
becomes just as vulnerable to the aggressive kind of user space programs
as other DSA switches are (ok, users can also create 8021q uppers on top
of the DSA master in the case of sja1105, but in future patches we can
easily deny that, but it still doesn't change the fact that VLAN-tagged
packets can still be injected over raw sockets).
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently it is possible for an attacker to craft packets with a fake
DSA tag and send them to us, and our user ports will accept them and
preserve that VLAN when transmitting towards the CPU. Then the tagger
will be misled into thinking that the packets came on a different port
than they really came on.

Up until recently there wasn't a good option to prevent this from
happening. In SJA1105P and later, the MAC Configuration Table introduced
two options called:
- DRPSITAG: Drop Single Inner Tagged Frames
- DRPSOTAG: Drop Single Outer Tagged Frames

Because the sja1105 driver classifies all VLANs as "outer VLANs" (S-Tags),
it would be in principle possible to enable the DRPSOTAG bit on ports
using tag_8021q, and drop on ingress all packets which have a VLAN tag.
When the switch is VLAN-unaware, this works, because it uses a custom
TPID of 0xdadb, so any "tagged" packets received on a user port are
probably a spoofing attempt. But when the switch overall is VLAN-aware,
and some ports are standalone (therefore they use tag_8021q), the TPID
is 0x8100, and the port can receive a mix of untagged and VLAN-tagged
packets. The untagged ones will be classified to the tag_8021q pvid, and
the tagged ones to the VLAN ID from the packet header. Yes, it is true
that since commit 4fbc08bd ("net: dsa: sja1105: deny 8021q uppers on
ports") we no longer support this mixed mode, but that is a temporary
limitation which will eventually be lifted. It would be nice to not
introduce one more restriction via DRPSOTAG, which would make the
standalone ports of a VLAN-aware switch drop genuinely VLAN-tagged
packets.

Also, the DRPSOTAG bit is not available on the first generation of
switches (SJA1105E, SJA1105T). So since one of the key features of this
driver is compatibility across switch generations, this makes it an even
less desirable approach.

The breakthrough comes from commit bef0746c ("net: dsa: sja1105:
make sure untagged packets are dropped on ingress ports with no pvid"),
where it became obvious that untagged packets are not dropped even if
the ingress port is not in the VMEMB_PORT vector of that port's pvid.
However, VLAN-tagged packets are subject to VLAN ingress
checking/dropping. This means that instead of using the catch-all
DRPSOTAG bit introduced in SJA1105P, we can drop tagged packets on a
per-VLAN basis, and this is already compatible with SJA1105E/T.

This patch adds an "allowed_ingress" argument to sja1105_vlan_add(), and
we call it with "false" for tag_8021q VLANs on user ports. The tag_8021q
VLANs still need to be allowed, of course, on ingress to DSA ports and
CPU ports.

We also need to refine the drop_untagged check in sja1105_commit_pvid to
make it not freak out about this new configuration. Currently it will
try to keep the configuration consistent between untagged and pvid-tagged
packets, so if the pvid of a port is 1 but VLAN 1 is not in VMEMB_PORT,
packets tagged with VID 1 will behave the same as untagged packets, and
be dropped. This behavior is what we want for ports under a VLAN-aware
bridge, but for the ports with a tag_8021q pvid, we want untagged
packets to be accepted, but packets tagged with a header recognized by
the switch as a tag_8021q VLAN to be dropped. So only restrict the
drop_untagged check to apply to the bridge_pvid, not to the tag_8021q_pvid.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver was relying on dsa_slave_vlan_rx_add_vid to add VLAN ID 0. After
the blamed commit, VLAN ID 0 won't be set up anymore, breaking software
bridging fallback on VLAN-unaware bridges.

Manually set up VLAN ID 0 to fix this.

Fixes: 06cfb2df ("net: dsa: don't advertise 'rx-vlan-filter' when not needed")
Signed-off-by: NDENG Qingfang <dqfext@gmail.com>
Reviewed-by: NVladimir Oltean <olteanv@gmail.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In early erratas this issue only covered port 0 when changing from
[x]MII (rev A 3.6). In subsequent errata versions this errata changed to
cover the additional "Hardware reset in CPU managed mode" condition, and
removed the note specifying that it only applied to port 0.

In designs where the device is configured with CPU managed mode
(CPU_MGD), on reset all SERDES ports (p0, p9, p10) have a stuck power
down bit and require this initial power up procedure. As such apply this
errata to all three SERDES ports of the mv88e6393x.
Signed-off-by: NNathan Rossi <nathan.rossi@digi.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As explained in commit e358bef7 ("net: dsa: Give drivers the chance
to veto certain upper devices"), the hellcreek driver uses some tricks
to comply with the network stack expectations: it enforces port
separation in standalone mode using VLANs. For untagged traffic,
bridging between ports is prevented by using different PVIDs, and for
VLAN-tagged traffic, it never accepts 8021q uppers with the same VID on
two ports, so packets with one VLAN cannot leak from one port to another.

That is almost fine*, and has worked because hellcreek relied on an
implicit behavior of the DSA core that was changed by the previous
patch: the standalone ports declare the 'rx-vlan-filter' feature as 'on
[fixed]'. Since most of the DSA drivers are actually VLAN-unaware in
standalone mode, that feature was actually incorrectly reflecting the
hardware/driver state, so there was a desire to fix it. This leaves the
hellcreek driver in a situation where it has to explicitly request this
behavior from the DSA framework.

We configure the ports as follows:

- Standalone: 'rx-vlan-filter' is on. An 8021q upper on top of a
  standalone hellcreek port will go through dsa_slave_vlan_rx_add_vid
  and will add a VLAN to the hardware tables, giving the driver the
  opportunity to refuse it through .port_prechangeupper.

- Bridged with vlan_filtering=0: 'rx-vlan-filter' is off. An 8021q upper
  on top of a bridged hellcreek port will not go through
  dsa_slave_vlan_rx_add_vid, because there will not be any attempt to
  offload this VLAN. The driver already disables VLAN awareness, so that
  upper should receive the traffic it needs.

- Bridged with vlan_filtering=1: 'rx-vlan-filter' is on. An 8021q upper
  on top of a bridged hellcreek port will call dsa_slave_vlan_rx_add_vid,
  and can again be vetoed through .port_prechangeupper.

*It is not actually completely fine, because if I follow through
correctly, we can have the following situation:

ip link add br0 type bridge vlan_filtering 0
ip link set lan0 master br0 # lan0 now becomes VLAN-unaware
ip link set lan0 nomaster # lan0 fails to become VLAN-aware again, therefore breaking isolation

This patch fixes that corner case by extending the DSA core logic, based
on this requested attribute, to change the VLAN awareness state of the
switch (port) when it leaves the bridge.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Acked-by: NKurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to transmit more restrictions in future patches, convert this
one to netlink extack.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to reject some more configurations in future patches, convert
the existing one to netlink extack.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for tag_sja1105 running on non-sja1105 DSA ports, by making
sure that every time we dereference dp->priv, we check the switch's
dsa_switch_ops (otherwise we access a struct sja1105_port structure that
is in fact something else).

This adds an unconditional build-time dependency between sja1105 being
built as module => tag_sja1105 must also be built as module. This was
there only for PTP before.

Some sane defaults must also take place when not running on sja1105
hardware. These are:

- sja1105_xmit_tpid: the sja1105 driver uses different VLAN protocols
  depending on VLAN awareness and switch revision (when an encapsulated
  VLAN must be sent). Default to 0x8100.

- sja1105_rcv_meta_state_machine: this aggregates PTP frames with their
  metadata timestamp frames. When running on non-sja1105 hardware, don't
  do that and accept all frames unmodified.

- sja1105_defer_xmit: calls sja1105_port_deferred_xmit in sja1105_main.c
  which writes a management route over SPI. When not running on sja1105
  hardware, bypass the SPI write and send the frame as-is.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It seems that of_find_compatible_node has a weird calling convention in
which it calls of_node_put() on the "from" node argument, instead of
leaving that up to the caller. This comes from the fact that
of_find_compatible_node with a non-NULL "from" argument it only supposed
to be used as the iterator function of for_each_compatible_node(). OF
iterator functions call of_node_get on the next OF node and of_node_put()
on the previous one.

When of_find_compatible_node calls of_node_put, it actually never
expects the refcount to drop to zero, because the call is done under the
atomic devtree_lock context, and when the refcount drops to zero it
triggers a kobject and a sysfs file deletion, which assume blocking
context.

So any driver call to of_find_compatible_node is probably buggy because
an unexpected of_node_put() takes place.

What should be done is to use the of_get_compatible_child() function.

Fixes: 5a8f0974 ("net: dsa: sja1105: register the MDIO buses for 100base-T1 and 100base-TX")
Link: https://lore.kernel.org/netdev/20210814010139.kzryimmp4rizlznt@skbuf/Suggested-by: NFrank Rowand <frowand.list@gmail.com>
Suggested-by: NRob Herring <robh+dt@kernel.org>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sja1105 driver's initialization and teardown sequence is a chaotic
mess that has gathered a lot of cruft over time. It works because there
is no strict dependency between the functions, but it could be improved.

The basic principle that teardown should be the exact reverse of setup
is obviously not held. We have initialization steps (sja1105_tas_setup,
sja1105_flower_setup) in the probe method that are torn down in the DSA
.teardown method instead of driver unbind time.

We also have code after the dsa_register_switch() call, which implicitly
means after the .setup() method has finished, which is pretty unusual.

Also, sja1105_teardown() has calls set up in a different order than the
error path of sja1105_setup(): see the reversed ordering between
sja1105_ptp_clock_unregister and sja1105_mdiobus_unregister.

Also, sja1105_static_config_load() is called towards the end of
sja1105_setup(), but sja1105_static_config_free() is also towards the
end of the error path and teardown path. The static_config_load() call
should be earlier.

Also, making and breaking the connections between struct sja1105_port
and struct dsa_port could be refactored into dedicated functions, makes
the code easier to follow.

We move some code from the DSA .setup() method into the probe method,
like the device tree parsing, and we move some code from the probe
method into the DSA .setup() method to be symmetric with its placement
in the DSA .teardown() method, which is nice because the unbind function
has a single call to dsa_unregister_switch(). Example of the latter type
of code movement are the connections between ports mentioned above, they
are now in the .setup() method.

Finally, due to fact that the kthread_init_worker() call is no longer
in sja1105_probe() - located towards the bottom of the file - but in
sja1105_setup() - located much higher - there is an inverse ordering
with the worker function declaration, sja1105_port_deferred_xmit. To
avoid that, the entire sja1105_setup() and sja1105_teardown() functions
are moved towards the bottom of the file.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The felix DSA driver, which is a wrapper over the same hardware class as
ocelot, is integrated with phylink, but ocelot is using the plain PHY
library. It makes sense to bring together the two implementations, which
is what this patch achieves.

This is a large patch and hard to break up, but it does the following:

The existing ocelot_adjust_link writes some registers, and
felix_phylink_mac_link_up writes some registers, some of them are
common, but both functions write to some registers to which the other
doesn't.

The main reasons for this are:
- Felix switches so far have used an NXP PCS so they had no need to
  write the PCS1G registers that ocelot_adjust_link writes
- Felix switches have the MAC fixed at 1G, so some of the MAC speed
  changes actually break the link and must be avoided.

The naming conventions for the functions introduced in this patch are:
- vsc7514_phylink_{mac_config,validate} are specific to the Ocelot
  instantiations and placed in ocelot_net.c which is built only for the
  ocelot switchdev driver.
- ocelot_phylink_mac_link_{up,down} are shared between the ocelot
  switchdev driver and the felix DSA driver (they are put in the common
  lib).

One by one, the registers written by ocelot_adjust_link are:

DEV_MAC_MODE_CFG - felix_phylink_mac_link_up had no need to write this
                   register since its out-of-reset value was fine and
                   did not need changing. The write is moved to the
                   common ocelot_phylink_mac_link_up and on felix it is
                   guarded by a quirk bit that makes the written value
                   identical with the out-of-reset one
DEV_PORT_MISC - runtime invariant, was moved to vsc7514_phylink_mac_config
PCS1G_MODE_CFG - same as above
PCS1G_SD_CFG - same as above
PCS1G_CFG - same as above
PCS1G_ANEG_CFG - same as above
PCS1G_LB_CFG - same as above
DEV_MAC_ENA_CFG - both ocelot_adjust_link and ocelot_port_disable
                  touched this. felix_phylink_mac_link_{up,down} also
                  do. We go with what felix does and put it in
                  ocelot_phylink_mac_link_up.
DEV_CLOCK_CFG - ocelot_adjust_link and felix_phylink_mac_link_up both
                write this, but to different values. Move to the common
                ocelot_phylink_mac_link_up and make sure via the quirk
                that the old values are preserved for both.
ANA_PFC_PFC_CFG - ocelot_adjust_link wrote this, felix_phylink_mac_link_up
                  did not. Runtime invariant, speed does not matter since
                  PFC is disabled via the RX_PFC_ENA bits which are cleared.
                  Move to vsc7514_phylink_mac_config.
QSYS_SWITCH_PORT_MODE_PORT_ENA - both ocelot_adjust_link and
                                 felix_phylink_mac_link_{up,down} wrote
                                 this. Ocelot also wrote this register
                                 from ocelot_port_disable. Keep what
                                 felix did, move in ocelot_phylink_mac_link_{up,down}
                                 and delete ocelot_port_disable.
ANA_POL_FLOWC - same as above
SYS_MAC_FC_CFG - same as above, except slight behavior change. Whereas
                 ocelot always enabled RX and TX flow control, felix
                 listened to phylink (for the most part, at least - see
                 the 2500base-X comment).

The registers which only felix_phylink_mac_link_up wrote are:

SYS_PAUSE_CFG_PAUSE_ENA - this is why I am not sure that flow control
                          worked on ocelot. Not it should, since the
                          code is shared with felix where it does.
ANA_PORT_PORT_CFG - this is a Frame Analyzer block register, phylink
                    should be the one touching them, deleted.

Other changes:

- The old phylib registration code was in mscc_ocelot_init_ports. It is
  hard to work with 2 levels of indentation already in, and with hard to
  follow teardown logic. The new phylink registration code was moved
  inside ocelot_probe_port(), right between alloc_etherdev() and
  register_netdev(). It could not be done before (=> outside of)
  ocelot_probe_port() because ocelot_probe_port() allocates the struct
  ocelot_port which we then use to assign ocelot_port->phy_mode to. It
  is more preferable to me to have all PHY handling logic inside the
  same function.
- On the same topic: struct ocelot_port_private :: serdes is only used
  in ocelot_port_open to set the SERDES protocol to Ethernet. This is
  logically a runtime invariant and can be done just once, when the port
  registers with phylink. We therefore don't even need to keep the
  serdes reference inside struct ocelot_port_private, or to use the devm
  variant of of_phy_get().
- Phylink needs a valid phy-mode for phylink_create() to succeed, and
  the existing device tree bindings in arch/mips/boot/dts/mscc/ocelot_pcb120.dts
  don't define one for the internal PHY ports. So we patch
  PHY_INTERFACE_MODE_NA into PHY_INTERFACE_MODE_INTERNAL.
- There was a strategically placed:

	switch (priv->phy_mode) {
	case PHY_INTERFACE_MODE_NA:
	        continue;

  which made the code skip the serdes initialization for the internal
  PHY ports. Frankly that is not all that obvious, so now we explicitly
  initialize the serdes under an "if" condition and not rely on code
  jumps, so everything is clearer.
- There was a write of OCELOT_SPEED_1000 to DEV_CLOCK_CFG for QSGMII
  ports. Since that is in fact the default value for the register field
  DEV_CLOCK_CFG_LINK_SPEED, I can only guess the intention was to clear
  the adjacent fields, MAC_TX_RST and MAC_RX_RST, aka take the port out
  of reset, which does match the comment. I don't even want to know why
  this code is placed there, but if there is indeed an issue that all
  ports that share a QSGMII lane must all be up, then this logic is
  already buggy, since mscc_ocelot_init_ports iterates using
  for_each_available_child_of_node, so nobody prevents the user from
  putting a 'status = "disabled";' for some QSGMII ports which would
  break the driver's assumption.
  In any case, in the eventuality that I'm right, we would have yet
  another issue if ocelot_phylink_mac_link_down would reset those ports
  and that would be forbidden, so since the ocelot_adjust_link logic did
  not do that (maybe for a reason), add another quirk to preserve the
  old logic.

The ocelot driver teardown goes through all ports in one fell swoop.
When initialization of one port fails, the ocelot->ports[port] pointer
for that is reset to NULL, and teardown is done only for non-NULL ports,
so there is no reason to do partial teardowns, let the central
mscc_ocelot_release_ports() do its job.

Tested bind, unbind, rebind, link up, link down, speed change on mock-up
hardware (modified the driver to probe on Felix VSC9959). Also
regression tested the felix DSA driver. Could not test the Ocelot
specific bits (PCS1G, SERDES, device tree bindings).
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ocelot_port_enable touches ANA_PORT_PORT_CFG, which has the following
fields:

- LOCKED_PORTMOVE_CPU, LEARNDROP, LEARNCPU, LEARNAUTO, RECV_ENA, all of
  which are written with their hardware default values, also runtime
  invariants. So it makes no sense to write these during every .ndo_open.

- PORTID_VAL: this field has an out-of-reset value of zero for all ports
  and must be initialized by software. Additionally, the
  ocelot_setup_logical_port_ids() code path sets up different logical
  port IDs for the ports in a hardware LAG, and we absolutely don't want
  .ndo_open to interfere there and reset those values.

So in fact the write from ocelot_port_enable can better be moved to
ocelot_init_port, and the .ndo_open hook deleted.

ocelot_port_disable touches DEV_MAC_ENA_CFG and QSYS_SWITCH_PORT_MODE_PORT_ENA,
in an attempt to undo what ocelot_adjust_link did. But since .ndo_stop
does not get called each time the link falls (i.e. this isn't a
substitute for .phylink_mac_link_down), felix already does better at
this by writing those registers already in felix_phylink_mac_link_down.

So keep ocelot_port_disable (for now, until ocelot is converted to
phylink too), and just delete the felix call to it, which is not
necessary.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 'imply' keyword does not do what most people think it does, it only
politely asks Kconfig to turn on another symbol, but does not prevent
it from being disabled manually or built as a loadable module when the
user is built-in. In the ICE driver, the latter now causes a link failure:

aarch64-linux-ld: drivers/net/ethernet/intel/ice/ice_main.o: in function `ice_eth_ioctl':
ice_main.c:(.text+0x13b0): undefined reference to `ice_ptp_get_ts_config'
ice_main.c:(.text+0x13b0): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `ice_ptp_get_ts_config'
aarch64-linux-ld: ice_main.c:(.text+0x13bc): undefined reference to `ice_ptp_set_ts_config'
ice_main.c:(.text+0x13bc): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `ice_ptp_set_ts_config'
aarch64-linux-ld: drivers/net/ethernet/intel/ice/ice_main.o: in function `ice_prepare_for_reset':
ice_main.c:(.text+0x31fc): undefined reference to `ice_ptp_release'
ice_main.c:(.text+0x31fc): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `ice_ptp_release'
aarch64-linux-ld: drivers/net/ethernet/intel/ice/ice_main.o: in function `ice_rebuild':

This is a recurring problem in many drivers, and we have discussed
it several times befores, without reaching a consensus. I'm providing
a link to the previous email thread for reference, which discusses
some related problems.

To solve the dependency issue better than the 'imply' keyword, introduce a
separate Kconfig symbol "CONFIG_PTP_1588_CLOCK_OPTIONAL" that any driver
can depend on if it is able to use PTP support when available, but works
fine without it. Whenever CONFIG_PTP_1588_CLOCK=m, those drivers are
then prevented from being built-in, the same way as with a 'depends on
PTP_1588_CLOCK || !PTP_1588_CLOCK' dependency that does the same trick,
but that can be rather confusing when you first see it.

Since this should cover the dependencies correctly, the IS_REACHABLE()
hack in the header is no longer needed now, and can be turned back
into a normal IS_ENABLED() check. Any driver that gets the dependency
wrong will now cause a link time failure rather than being unable to use
PTP support when that is in a loadable module.

However, the two recently added ptp_get_vclocks_index() and
ptp_convert_timestamp() interfaces are only called from builtin code with
ethtool and socket timestamps, so keep the current behavior by stubbing
those out completely when PTP is in a loadable module. This should be
addressed properly in a follow-up.

As Richard suggested, we may want to actually turn PTP support into a
'bool' option later on, preventing it from being a loadable module
altogether, which would be one way to solve the problem with the ethtool
interface.

Fixes: 06c16d89 ("ice: register 1588 PTP clock device object for E810 devices")
Link: https://lore.kernel.org/netdev/20210804121318.337276-1-arnd@kernel.org/
Link: https://lore.kernel.org/netdev/CAK8P3a06enZOf=XyZ+zcAwBczv41UuCTz+=0FMf2gBz1_cOnZQ@mail.gmail.com/
Link: https://lore.kernel.org/netdev/CAK8P3a3=eOxE-K25754+fB_-i_0BZzf9a9RfPTX3ppSwu9WZXw@mail.gmail.com/
Link: https://lore.kernel.org/netdev/20210726084540.3282344-1-arnd@kernel.org/Acked-by: NShannon Nelson <snelson@pensando.io>
Acked-by: NJacob Keller <jacob.e.keller@intel.com>
Acked-by: NRichard Cochran <richardcochran@gmail.com>
Reviewed-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210812183509.1362782-1-arnd@kernel.orgSigned-off-by: NJakub Kicinski <kuba@kernel.org>

The call to sja1105_mdiobus_unregister is present in the error path but
absent from the main driver unbind path.

Fixes: 5a8f0974 ("net: dsa: sja1105: register the MDIO buses for 100base-T1 and 100base-TX")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a port leaves a VLAN-aware bridge, the current code does not clear
other ports' matrix field bit. If the bridge is later set to VLAN-unaware
mode, traffic in the bridge may leak to that port.

Remove the VLAN filtering check in mt7530_port_bridge_leave.

Fixes: 474a2dda ("net: dsa: mt7530: fix VLAN traffic leaks")
Fixes: 83163f7d ("net: dsa: mediatek: add VLAN support for MT7530")
Signed-off-by: NDENG Qingfang <dqfext@gmail.com>
Reviewed-by: NVladimir Oltean <olteanv@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rtnl_fdb_dump() has logic to split a dump of PF_BRIDGE neighbors into
multiple netlink skbs if the buffer provided by user space is too small
(one buffer will typically handle a few hundred FDB entries).

When the current buffer becomes full, nlmsg_put() in
dsa_slave_port_fdb_do_dump() returns -EMSGSIZE and DSA saves the index
of the last dumped FDB entry, returns to rtnl_fdb_dump() up to that
point, and then the dump resumes on the same port with a new skb, and
FDB entries up to the saved index are simply skipped.

Since dsa_slave_port_fdb_do_dump() is pointed to by the "cb" passed to
drivers, then drivers must check for the -EMSGSIZE error code returned
by it. Otherwise, when a netlink skb becomes full, DSA will no longer
save newly dumped FDB entries to it, but the driver will continue
dumping. So FDB entries will be missing from the dump.

Fix the broken backpressure by propagating the "cb" return code and
allow rtnl_fdb_dump() to restart the FDB dump with a new skb.

Fixes: 291d1e72 ("net: dsa: sja1105: Add support for FDB and MDB management")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rtnl_fdb_dump() has logic to split a dump of PF_BRIDGE neighbors into
multiple netlink skbs if the buffer provided by user space is too small
(one buffer will typically handle a few hundred FDB entries).

When the current buffer becomes full, nlmsg_put() in
dsa_slave_port_fdb_do_dump() returns -EMSGSIZE and DSA saves the index
of the last dumped FDB entry, returns to rtnl_fdb_dump() up to that
point, and then the dump resumes on the same port with a new skb, and
FDB entries up to the saved index are simply skipped.

Since dsa_slave_port_fdb_do_dump() is pointed to by the "cb" passed to
drivers, then drivers must check for the -EMSGSIZE error code returned
by it. Otherwise, when a netlink skb becomes full, DSA will no longer
save newly dumped FDB entries to it, but the driver will continue
dumping. So FDB entries will be missing from the dump.

Fix the broken backpressure by propagating the "cb" return code and
allow rtnl_fdb_dump() to restart the FDB dump with a new skb.

Fixes: 58c59ef9 ("net: dsa: lantiq: Add Forwarding Database access")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rtnl_fdb_dump() has logic to split a dump of PF_BRIDGE neighbors into
multiple netlink skbs if the buffer provided by user space is too small
(one buffer will typically handle a few hundred FDB entries).

When the current buffer becomes full, nlmsg_put() in
dsa_slave_port_fdb_do_dump() returns -EMSGSIZE and DSA saves the index
of the last dumped FDB entry, returns to rtnl_fdb_dump() up to that
point, and then the dump resumes on the same port with a new skb, and
FDB entries up to the saved index are simply skipped.

Since dsa_slave_port_fdb_do_dump() is pointed to by the "cb" passed to
drivers, then drivers must check for the -EMSGSIZE error code returned
by it. Otherwise, when a netlink skb becomes full, DSA will no longer
save newly dumped FDB entries to it, but the driver will continue
dumping. So FDB entries will be missing from the dump.

Fix the broken backpressure by propagating the "cb" return code and
allow rtnl_fdb_dump() to restart the FDB dump with a new skb.

Fixes: ab335349 ("net: dsa: lan9303: Add port_fast_age and port_fdb_dump methods")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rtnl_fdb_dump() has logic to split a dump of PF_BRIDGE neighbors into
multiple netlink skbs if the buffer provided by user space is too small
(one buffer will typically handle a few hundred FDB entries).

When the current buffer becomes full, nlmsg_put() in
dsa_slave_port_fdb_do_dump() returns -EMSGSIZE and DSA saves the index
of the last dumped FDB entry, returns to rtnl_fdb_dump() up to that
point, and then the dump resumes on the same port with a new skb, and
FDB entries up to the saved index are simply skipped.

Since dsa_slave_port_fdb_do_dump() is pointed to by the "cb" passed to
drivers, then drivers must check for the -EMSGSIZE error code returned
by it. Otherwise, when a netlink skb becomes full, DSA will no longer
save newly dumped FDB entries to it, but the driver will continue
dumping. So FDB entries will be missing from the dump.

Fix the broken backpressure by propagating the "cb" return code and
allow rtnl_fdb_dump() to restart the FDB dump with a new skb.

Fixes: e4b27ebc ("net: dsa: Add DSA driver for Hirschmann Hellcreek switches")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NKurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The magic number 4 in VLAN table lookup was the number of entries we
can read and write at once.  Using phy_port_cnt here doesn't make
sense and presumably broke VLAN filtering for 3-port switches.  Change
it back to 4.

Fixes: 4ce2a984 ("net: dsa: microchip: ksz8795: use phy_port_cnt ...")
Signed-off-by: NBen Hutchings <ben.hutchings@mind.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently ksz8_port_vlan_filtering() sets or clears the VLAN Enable
hardware flag.  That controls discarding of packets with a VID that
has not been enabled for any port on the switch.

Since it is a global flag, set the dsa_switch::vlan_filtering_is_global
flag so that the DSA core understands this can't be controlled per
port.

When VLAN filtering is enabled, the switch should also discard packets
with a VID that's not enabled on the ingress port.  Set or clear each
external port's VLAN Ingress Filter flag in ksz8_port_vlan_filtering()
to make that happen.

Fixes: e66f840c ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: NBen Hutchings <ben.hutchings@mind.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On the CPU port, we can support both tagged and untagged VLANs at the
same time by doing any necessary untagging in software rather than
hardware.  To enable that, keep the CPU port's Remove Tag flag cleared
and set the dsa_switch::untag_bridge_pvid flag.

Fixes: e66f840c ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: NBen Hutchings <ben.hutchings@mind.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a VLAN is deleted from a port, the flags in struct
switchdev_obj_port_vlan are always 0.  ksz8_port_vlan_del() copies the
BRIDGE_VLAN_INFO_UNTAGGED flag to the port's Tag Removal flag, and
therefore always clears it.

In case there are multiple VLANs configured as untagged on this port -
which seems useless, but is allowed - deleting one of them changes the
remaining VLANs to be tagged.

It's only ever necessary to change this flag when a VLAN is added to
the port, so leave it unchanged in ksz8_port_vlan_del().

Fixes: e66f840c ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: NBen Hutchings <ben.hutchings@mind.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The switches supported by ksz8795 only have a per-port flag for Tag
Removal.  This means it is not possible to support both tagged and
untagged VLANs on the same port.  Reject attempts to add a VLAN that
requires the flag to be changed, unless there are no VLANs currently
configured.

VID 0 is excluded from this check since it is untagged regardless of
the state of the flag.

On the CPU port we could support tagged and untagged VLANs at the same
time.  This will be enabled by a later patch.

Fixes: e66f840c ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: NBen Hutchings <ben.hutchings@mind.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ksz8795 has never actually enabled PVID tag insertion, and it also
programmed the PVID incorrectly.  To fix this:

* Allow tag insertion to be controlled per ingress port.  On most
  chips, set bit 2 in Global Control 19.  On KSZ88x3 this control
  flag doesn't exist.

* When adding a PVID:
  - Set the appropriate register bits to enable tag insertion on
    egress at every other port if this was the packet's ingress port.
  - Mask *out* the VID from the default tag, before or-ing in the new
    PVID.

* When removing a PVID:
  - Clear the same control bits to disable tag insertion.
  - Don't update the default tag.  This wasn't doing anything useful.

Fixes: e66f840c ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: NBen Hutchings <ben.hutchings@mind.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ksz_read64() currently does some dubious byte-swapping on the two
halves of a 64-bit register, and then only returns the high bits.
Replace this with a straightforward expression.

Fixes: e66f840c ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: NBen Hutchings <ben.hutchings@mind.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Delete the dynamically learned FDB entries when the STP state changes
and when address learning is disabled.

On sja1105 there is no shorthand SPI command for this, so we need to
walk through the entire FDB to delete.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that DSA keeps track of the port learning state, it becomes
superfluous to keep an additional variable with this information in the
sja1105 driver. Remove it.

The DSA core's learning state is present in struct dsa_port *dp.
To avoid the antipattern where we iterate through a DSA switch's
ports and then call dsa_to_port to obtain the "dp" reference (which is
bad because dsa_to_port iterates through the DSA switch tree once
again), just iterate through the dst->ports and operate on those
directly.

The sja1105 had an extra use of priv->learn_ena on non-user ports. DSA
does not touch the learning state of those ports - drivers are free to
do what they wish on them. Mark that information with a comment in
struct dsa_port and let sja1105 set dp->learning for cascade ports.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently DSA leaves it down to device drivers to fast age the FDB on a
port when address learning is disabled on it. There are 2 reasons for
doing that in the first place:

- when address learning is disabled by user space, through
  IFLA_BRPORT_LEARNING or the brport_attr_learning sysfs, what user
  space typically wants to achieve is to operate in a mode with no
  dynamic FDB entry on that port. But if the port is already up, some
  addresses might have been already learned on it, and it seems silly to
  wait for 5 minutes for them to expire until something useful can be
  done.

- when a port leaves a bridge and becomes standalone, DSA turns off
  address learning on it. This also has the nice side effect of flushing
  the dynamically learned bridge FDB entries on it, which is a good idea
  because standalone ports should not have bridge FDB entries on them.

We let drivers manage fast ageing under this condition because if DSA
were to do it, it would need to track each port's learning state, and
act upon the transition, which it currently doesn't.

But there are 2 reasons why doing it is better after all:

- drivers might get it wrong and not do it (see b53_port_set_learning)

- we would like to flush the dynamic entries from the software bridge
  too, and letting drivers do that would be another pain point

So track the port learning state and trigger a fast age process
automatically within DSA.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make sure that all external port are actually isolated from each other,
so no packets are leaked.

Fixes: ec6698c2 ("net: dsa: add support for Atheros AR9331 built-in switch")
Signed-off-by: NOleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the missing RxUnicast counter.

Fixes: b8f126a8 ("net-next: dsa: add dsa support for Mediatek MT7530 switch")
Signed-off-by: NDENG Qingfang <dqfext@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver currently still accepts untagged frames on VLAN-aware ports
without PVID. Use PVC.ACC_FRM to drop untagged frames in that case.
Signed-off-by: NDENG Qingfang <dqfext@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 08cc83cc ("net: dsa: add support for BRIDGE_MROUTER
attribute") added an option for users to turn off multicast flooding
towards the CPU if they turn off the IGMP querier on a bridge which
already has enslaved ports (echo 0 > /sys/class/net/br0/bridge/multicast_router).

And commit a8b659e7 ("net: dsa: act as passthrough for bridge port flags")
simply papered over that issue, because it moved the decision to flood
the CPU with multicast (or not) from the DSA core down to individual drivers,
instead of taking a more radical position then.

The truth is that disabling multicast flooding to the CPU is simply
something we are not prepared to do now, if at all. Some reasons:

- ICMP6 neighbor solicitation messages are unregistered multicast
  packets as far as the bridge is concerned. So if we stop flooding
  multicast, the outside world cannot ping the bridge device's IPv6
  link-local address.

- There might be foreign interfaces bridged with our DSA switch ports
  (sending a packet towards the host does not necessarily equal
  termination, but maybe software forwarding). So if there is no one
  interested in that multicast traffic in the local network stack, that
  doesn't mean nobody is.

- PTP over L4 (IPv4, IPv6) is multicast, but is unregistered as far as
  the bridge is concerned. This should reach the CPU port.

- The switch driver might not do FDB partitioning. And since we don't
  even bother to do more fine-grained flood disabling (such as "disable
  flooding _from_port_N_ towards the CPU port" as opposed to "disable
  flooding _from_any_port_ towards the CPU port"), this breaks standalone
  ports, or even multiple bridges where one has an IGMP querier and one
  doesn't.

Reverting the logic makes all of the above work.

Fixes: a8b659e7 ("net: dsa: act as passthrough for bridge port flags")
Fixes: 08cc83cc ("net: dsa: add support for BRIDGE_MROUTER attribute")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

DSA's idea of optimizing out multicast flooding to the CPU port leaves
quite a few holes open, so it should be reverted.

The mt7530 driver is the only new driver which added a .port_set_mrouter
implementation after the reorg from commit a8b659e7 ("net: dsa: act
as passthrough for bridge port flags"), so it needs to be reverted
separately so that the other revert commit can go a bit further down the
git history.

Fixes: 5a30833b ("net: dsa: mt7530: support MDB and bridge flag operations")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>