The SJA1110 has an extra configuration in the General Parameters Table
through which the user can select the buffer reservation config.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The SJA1110 is basically an SJA1105 with more ports, some integrated
PHYs (100base-T1 and 100base-TX) and an embedded microcontroller which
can be disabled, and the switch core can be controlled by a host running
Linux, over SPI.

This patch contains:
- the static and dynamic config packing functions, for the tables that
  are common with SJA1105
- one more static config tables which is "unique" to the SJA1110
  (actually it is a rehash of stuff that was placed somewhere else in
  SJA1105): the PCP Remapping Table
- a reset and clock configuration procedure for the SJA1110 switch.
  This resets just the switch subsystem, and gates off the clock which
  powers on the embedded microcontroller.
- an RGMII delay configuration procedure for SJA1110, which is very
  similar to SJA1105, but different enough for us to be unable to reuse
  it (this is a pattern that repeats itself)
- some adaptations to dynamic config table entries which are no longer
  programmed in the same way. For example, to delete a VLAN, you used to
  write an entry through the dynamic reconfiguration interface with the
  desired VLAN ID, and with the VALIDENT bit set to false. Now, the VLAN
  table entries contain a TYPE_ENTRY field, which must be set to zero
  (in a backwards-incompatible way) in order for the entry to be deleted,
  or to some other entry for the VLAN to match "inner tagged" or "outer
  tagged" packets.
- a similar thing for the static config: the xMII Mode Parameters Table
  encoding for SGMII and MII (the latter just when attached to a
  100base-TX PHY) just isn't what it used to be in SJA1105. They are
  identical, except there is an extra "special" bit which needs to be
  set. Set it.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that both RevMII as well as RevRMII exist, we can deprecate the
sja1105,role-mac and sja1105,role-phy properties and simply let the user
select that a port operates in MII PHY role by using
	phy-mode = "rev-mii";
or in RMII PHY role by using
	phy-mode = "rev-rmii";

There are no fixed-link MII or RMII properties in mainline device trees,
and the setup itself is fairly uncommon, so there shouldn't be risks of
breaking compatibility.
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>

The sja1105 driver has an intermediate way of determining whether the
RGMII delays should be applied by the PHY or by itself: by looking at
the port role (PHY or MAC). The port can be put in the PHY role either
explicitly (sja1105,role-phy) or implicitly (fixed-link).

We want to deprecate the sja1105,role-phy property, so all that remains
is the fixed-link property. Introduce a "fixed_link" array of booleans
in the driver, and use that to determine whether RGMII delays must be
applied or not.
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>

The SJA1105 has a static configuration comprised of a number of tables
with entries. Some of these can be read and modified at runtime as well,
through the dynamic configuration interface.

As a careful reader can notice from the comments in this file, the
software interface for accessing a table entry through the dynamic
reconfiguration is a bit of a no man's land, and varies wildly across
switch generations and even from one kind of table to another.

I have tried my best to come up with a software representation of a
'common denominator' SPI command to access a table entry through the
dynamic configuration interface:

struct sja1105_dyn_cmd {
	bool search;
	u64 valid; /* must be set to 1 */
	u64 rdwrset; /* 0 to read, 1 to write */
	u64 errors;
	u64 valident; /* 0 if entry is invalid, 1 if valid */
	u64 index;
};

Relevant to this patch is the VALIDENT bit, which for READ commands is
populated by the switch and lets us know if we're looking at junk or at
a real table entry.

In SJA1105, the dynamic reconfiguration interface for management routes
has notably not implemented the VALIDENT bit, leading to a workaround to
ignore this field in sja1105_dynamic_config_read(), as it will be set to
zero, but the data is valid nonetheless.

In SJA1110, this pattern has sadly been abused to death, and while there
are many more tables which can be read back over the dynamic config
interface compared to SJA1105, their handling isn't in any way more
uniform. Generally speaking, if there is a single possible entry in a
given table, and loading that table in the static config is mandatory as
per the documentation, then the VALIDENT bit is deemed as redundant and
more than likely not implemented.

So it is time to make the workaround more official, and add a bit to the
flags implemented by dynamic config tables. It will be used by more
tables when SJA1110 support arrives.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

In SJA1105, the xMII Mode Parameters Table field called PHY_MAC denotes
the 'role' of the port, be it a PHY or a MAC. This makes a difference in
the MII and RMII protocols, but RGMII is symmetric, so either PHY or MAC
settings result in the same hardware behavior.

The SJA1110 is different, and the RGMII ports only work when configured
in MAC mode, so keep the port roles in MAC mode unconditionally.

Why we had an RGMII port in the PHY role in the first place was because
we wanted to have a way in the driver to denote whether RGMII delays
should be applied based on the phy-mode property or not. This is already
done in sja1105_parse_rgmii_delays() based on an intermediary
struct sja1105_dt_port (which contains the port role). So it is a
logical fallacy to use the hardware configuration as a scratchpad for
driver data, it isn't necessary.

We can also remove the gating condition for applying RGMII delays only
for ports in the PHY role. The .setup_rgmii_delay() method looks at
the priv->rgmii_rx_delay[port] and priv->rgmii_tx_delay[port] properties
which are already populated properly (in the case of a port in the MAC
role they are false). Removing this condition generates a few more SPI
writes for these ports (clearing the RGMII delays) which are perhaps
useless for SJA1105P/Q/R/S, where we know that the delays are disabled
by default. But for SJA1110, the firmware on the embedded microcontroller
might have done something funny, so it's always a good idea to clear the
RGMII delays if that's what Linux expects.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

In order to support the new speed of 2500Mbps, the SJA1110 has achieved
the great performance of changing the encoding in the MAC Configuration
Table for the port speeds of 10, 100, 1000 compared to SJA1105.

Because this is a common driver, we need a layer of indirection in order
to program the hardware with the right values irrespective of switch
generation.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

On the SJA1105, all ports support the parallel "xMII" protocols (MII,
RMII, RGMII) except for port 4 on SJA1105R/S which supports only SGMII.
This was relatively easy to model, by special-casing the SGMII port.

On the SJA1110, certain ports can be pinmuxed between SGMII and xMII, or
between SGMII and an internal 100base-TX PHY. This creates problems,
because the driver's assumption so far was that if a port supports
SGMII, it uses SGMII.

We allow the device tree to tell us how the port pinmuxing is done, and
check that against a PHY interface type compatibility matrix for
plausibility.

The other big change is that instead of doing SGMII configuration based
on what the port supports, we do it based on what is the configured
phy_mode of the port.

The 2500base-x support added in this patch is not complete.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

So far we've succeeded in operating without keeping a copy of the
phy-mode in the driver, since we already have the static config and we
can look at the xMII Mode Parameters Table which already holds that
information.

But with the SJA1110, we cannot make the distinction between sgmii and
2500base-x, because to the hardware's static config, it's all SGMII.
So add a phy_mode property per port inside struct sja1105_private.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

Looking at the SGMII PCS from SJA1110, which is accessed indirectly
through a different base address as can be seen in the next patch, it
appears odd that the address accessed through indirection still
references the base address from the SJA1105S register map (first MDIO
register is at 0x1f0000), when it could index the SGMII registers
starting from zero.

Except that the 0x1f0000 is not a base address at all, it seems. It is
0x1f << 16 | 0x0000, and 0x1f is coding for the vendor-specific MMD2.
So, it turns out, the Synopsys PCS implements all its registers inside
the vendor-specific MMDs 1 and 2 (0x1e and 0x1f). This explains why the
PCS has no overlaps (for the other MMDs) with other register regions of
the switch (because no other MMDs are implemented).

Change the code to remove the SGMII "base address" and explicitly encode
the MMD for reads/writes. This will become necessary for SJA1110 support.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

The SJA1105 R and S switches have 1 SGMII port (port 4). Because there
is only one such port, there is no "port" parameter in the configuration
code for the SGMII PCS.

However, the SJA1110 can have up to 4 SGMII ports, each with its own
SGMII register map. So we need to generalize the logic.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

Since commit f2f3e09396be ("net: dsa: sja1105: be compatible with
"ethernet-ports" OF node name"), DSA supports the "ethernet-ports" name
for the container node of the ports, but the sja1105 driver doesn't,
because it handles some device tree parsing of its own.

Add the second node name as a fallback.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

The shared frame buffer of the SJA1110 is larger than that of SJA1105,
which is natural due to the fact that there are more ports.

Introduce yet another property in struct sja1105_info which encodes the
maximum number of 128 byte blocks that can be used for frame buffers.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The SJA1110 policer array is similar in layout with SJA1105, except it
contains one multicast policer per port at the end.

Detect the presence of multicast policers based on the maximum number of
supported L2 Policing Table entries, and make those policers have a
shared index equal to the port's default policer. Letting the user
configure these policers is not supported at the moment.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using sja1105_xfer_buf results in a higher overhead and is harder to
read.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Due to the fact that the port count is different, some static config
tables have a different number of elements in SJA1105 compared to
SJA1110. Such an example is the L2 Policing table, which has 45 entries
in SJA1105 (one per port x traffic class, and one broadcast policer per
port) and 110 entries in SJA1110 (one per port x traffic class, one
broadcast and one multicast policer per port).

Similarly, the MAC Configuration Table, the L2 Forwarding table, all
have a different number of elements simply because the port count is
different, and although this can be accounted for by looking at
ds->ports, the policing table can't because of the presence of the extra
multicast policers.

The common denominator for the static config initializers for these
tables is that they must set up all the entries within that table.
So the simplest way to account for these differences in a uniform manner
is to look at struct sja1105_table_ops::max_entry_count. For the sake of
uniformity, this patch makes that change also for tables whose number of
elements did not change in SJA1110, like the xMII Mode Parameters, the
L2 Lookup Parameters, General Parameters, AVB Parameters (all of these
are singleton tables with a single entry).
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are two distinct code paths which enter sja1105_clocking.c, one
through sja1105_clocking_setup() and the other through
sja1105_clocking_setup_port():

sja1105_static_config_reload      sja1105_setup
              |                         |
              |      +------------------+
              |      |
              v      v
   sja1105_clocking_setup               sja1105_adjust_port_config
                 |                                   |
                 v                                   |
      sja1105_clocking_setup_port <------------------+

As opposed to SJA1105, the SJA1110 does not need any configuration of
the Clock Generation Unit in order for xMII ports to work. Just RGMII
internal delays need to be configured, and that is done inside
sja1105_clocking_setup_port for the RGMII ports.

So this patch introduces the concept of a "reserved address", which the
CGU configuration functions from sja1105_clocking.c must check before
proceeding to do anything. The SJA1110 will have reserved addresses for
the CGU PLLs for MII/RMII/RGMII.

Additionally, make sja1105_clocking_setup() a function pointer so it can
be overridden by the SJA1110. Even though nothing port-related needs to
be done in the CGU, there are some operations such as disabling the
watchdog clock which are unique to the SJA1110.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If @port is unused, then dsa_upstream_port(ds, port) returns @port,
which means we cannot assume the CPU port can be retrieved this way.

The sja1105 switches support a single CPU port, so just iterate over the
switch ports and stop at the first CPU port we see.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a SJA1105_MAX_NUM_PORTS macro which at the moment is equal to
SJA1105_NUM_PORTS (5). With the introduction of SJA1110, these
structures will need to hold information for up to 11 ports.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Do not put unused ports in the forwarding domain, and do not allocate
FDB entries for dynamic address learning for them.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sja1105 driver will gain support for the next-gen SJA1110 switch,
which is very similar except for the fact it has more than 5 ports.

So we need to replace the hardcoded SJA1105_NUM_PORTS in this driver
with ds->num_ports. This patch is as mechanical as possible (save for
the fact that ds->num_ports is not an integer constant expression).
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When running this sequence of operations:

ip link add br0 type bridge vlan_filtering 1
ip link set swp4 master br0
bridge vlan add dev swp4 vid 1

We observe the traffic sent on swp4 is still untagged, even though the
bridge has overwritten the existing VLAN entry:

port    vlan ids
swp4     1 PVID

br0      1 PVID Egress Untagged

This happens because we didn't consider that the 'bridge vlan add'
command just overwrites VLANs like it's nothing. We treat the 'vid 1
pvid untagged' and the 'vid 1' as two separate VLANs, and the first
still has precedence when calling sja1105_build_vlan_table. Obviously
there is a disagreement regarding semantics, and we end up doing
something unexpected from the PoV of the bridge.

Let's actually consider an "existing VLAN" to be one which is on the
same port, and has the same VLAN ID, as one we already have, and update
it if it has different flags than we do.

The first blamed commit is the one introducing the bug, the second one
is the latest on top of which the bugfix still applies.

Fixes: ec5ae610 ("net: dsa: sja1105: save/restore VLANs using a delta commit method")
Fixes: 5899ee36 ("net: dsa: tag_8021q: add a context structure")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

One thing became visible when writing the blamed commit, and that was
that STP and PTP frames injected by net/dsa/tag_sja1105.c using the
deferred xmit mechanism are always classified to the pvid of the CPU
port, regardless of whatever VLAN there might be in these packets.

So a decision needed to be taken regarding the mechanism through which
we should ensure that delivery of STP and PTP traffic is possible when
we are in a VLAN awareness mode that involves tag_8021q. This is because
tag_8021q is not concerned with managing the pvid of the CPU port, since
as far as tag_8021q is concerned, no traffic should be sent as untagged
from the CPU port. So we end up not actually having a pvid on the CPU
port if we only listen to tag_8021q, and unless we do something about it.

The decision taken at the time was to keep VLAN 1 in the list of
priv->dsa_8021q_vlans, and make it a pvid of the CPU port. This ensures
that STP and PTP frames can always be sent to the outside world.

However there is a problem. If we do the following while we are in
the best_effort_vlan_filtering=true mode:

ip link add br0 type bridge vlan_filtering 1
ip link set swp2 master br0
bridge vlan del dev swp2 vid 1

Then untagged and pvid-tagged frames should be dropped. But we observe
that they aren't, and this is because of the precaution we took that VID
1 is always installed on all ports.

So clearly VLAN 1 is not good for this purpose. What about VLAN 0?
Well, VLAN 0 is managed by the 8021q module, and that module wants to
ensure that 802.1p tagged frames are always received by a port, and are
always transmitted as VLAN-tagged (with VLAN ID 0). Whereas we want our
STP and PTP frames to be untagged if the stack sent them as untagged -
we don't want the driver to just decide out of the blue that it adds
VID 0 to some packets.

So what to do?

Well, there is one other VLAN that is reserved, and that is 4095:
$ ip link add link swp2 name swp2.4095 type vlan id 4095
Error: 8021q: Invalid VLAN id.
$ bridge vlan add dev swp2 vid 4095
Error: bridge: Vlan id is invalid.

After we made this change, VLAN 1 is indeed forwarded and/or dropped
according to the bridge VLAN table, there are no further alterations
done by the sja1105 driver.

Fixes: ec5ae610 ("net: dsa: sja1105: save/restore VLANs using a delta commit method")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver continues probing when a port is configured for an
unsupported PHY interface type, instead it should stop.

Fixes: 8aa9ebcc ("net: dsa: Introduce driver for NXP SJA1105 5-port L2 switch")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If any of sja1105_static_config_load(), sja1105_clocking_setup() or
sja1105_devlink_setup() fails, we can't just return in the middle of
sja1105_setup() or memory will leak. Add a cleanup path.

Fixes: 0a7bdbc2 ("net: dsa: sja1105: move devlink param code to sja1105_devlink.c")
Fixes: 8aa9ebcc ("net: dsa: Introduce driver for NXP SJA1105 5-port L2 switch")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Unlike other drivers which pretty much end their .probe() execution with
dsa_register_switch(), the sja1105 does some extra stuff. When that
fails with -ENOMEM, the driver is quick to return that, forgetting to
call dsa_unregister_switch(). Not critical, but a bug nonetheless.

Fixes: 4d752508 ("net: dsa: sja1105: offload the Credit-Based Shaper qdisc")
Fixes: a68578c2 ("net: dsa: Make deferred_xmit private to sja1105")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

At the beginning of the sja1105_dynamic_config.c file there is a diagram
of the dynamic config interface layout:

 packed_buf

 |
 V
 +-----------------------------------------+------------------+
 |              ENTRY BUFFER               |  COMMAND BUFFER  |
 +-----------------------------------------+------------------+

 <----------------------- packed_size ------------------------>

So in order to pack/unpack the command bits into the buffer,
sja1105_vl_lookup_cmd_packing must first advance the buffer pointer by
the length of the entry. This is similar to what the other *cmd_packing
functions do.

This bug exists because the command packing function for P/Q/R/S was
copied from the E/T generation, and on E/T, the command was actually
embedded within the entry buffer itself.

Fixes: 94f94d4a ("net: dsa: sja1105: add static tables for virtual links")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current internal sja1105 driver API is optimized for retrieving many
statistics counters at once. But the switch does not do atomic snapshotting
for them anyway.

In case we start reporting the hardware port counters through
ndo_get_stats64 as well, not just ethtool, it would be good to be able
to read individual port counters and not all of them.

Additionally, since Arnd Bergmann's commit ae1804de ("dsa: sja1105:
dynamically allocate stats structure"), sja1105_get_ethtool_stats
allocates memory dynamically, since struct sja1105_port_status was
deemed to consume too much stack memory. That is not ideal.
The large structure is only needed because of the burst read.
If we read statistics one by one, we can consume less memory, and
we can avoid dynamic allocation.

Additionally, latency-sensitive interfaces such as PTP operations (for
phc2sys) might suffer if the SPI mutex is being held for too long, which
happens in the case of SPI burst reads. By reading counters one by one,
we give a chance for higher priority processes to preempt and take the
SPI bus mutex for accessing the PTP clock.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The queue levels are not counters, but instead they represent the
occupancy of the MAC TX queues. Having these in ethtool port counters is
not helpful, so remove them.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The static config of the sja1105 switch is a long stream of bytes which
is programmed to the hardware in chunks (portions with the chip select
continuously asserted) of max 256 bytes each. Each chunk is a
spi_message composed of 2 spi_transfers: the buffer with the data and a
preceding buffer with the SPI access header.

Only that certain SPI controllers, such as the spi-sc18is602 I2C-to-SPI
bridge, cannot keep the chip select asserted for that long.
The spi_max_transfer_size() and spi_max_message_size() functions are how
the controller can impose its hardware limitations upon the SPI
peripheral driver.

For the sja1105 driver to work with these controllers, both buffers must
be smaller than the transfer limit, and their sum must be smaller than
the message limit.

Regression-tested on a switch connected to a controller with no
limitations (spi-fsl-dspi) as well as with one with caps for both
max_transfer_size and max_message_size (spi-sc18is602).
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sja1105 driver has been described by Mark Brown as "not using the
[ SPI ] API at all idiomatically" due to the use of cs_change:
https://patchwork.kernel.org/project/netdevbpf/patch/20210520135031.2969183-1-olteanv@gmail.com/

According to include/linux/spi/spi.h, the chip select is supposed to be
asserted for the entire length of a SPI message, as long as cs_change is
false for all member transfers. The cs_change flag changes the following:

(i) When a non-final SPI transfer has cs_change = true, the chip select
    should temporarily deassert and then reassert starting with the next
    transfer.
(ii) When a final SPI transfer has cs_change = true, the chip select
     should remain asserted until the following SPI message.

The sja1105 driver only uses cs_change for its first property, to form a
single SPI message whose layout can be seen below:

                                             this is an entire, single spi_message
           _______________________________________________________________________________________________
          /                                                                                               \
          +-------------+---------------+-------------+---------------+ ... +-------------+---------------+
          | hdr_xfer[0] | chunk_xfer[0] | hdr_xfer[1] | chunk_xfer[1] |     | hdr_xfer[n] | chunk_xfer[n] |
          +-------------+---------------+-------------+---------------+ ... +-------------+---------------+
cs_change      false          true           false           true                false          false

           ____________________________  _____________________________       _____________________________
CS line __/                            \/                             \ ... /                             \__

The fact of the matter is that spi_max_message_size() has an ambiguous
meaning if any non-final transfer has cs_change = true.

If the SPI master has a limitation in that it cannot keep the chip
select asserted for more than, say, 200 bytes (like the spi-sc18is602),
the normal thing for it to do is to implement .max_transfer_size and
.max_message_size, and limit both to 200: in the "worst case" where
cs_change is always false, then the controller can, indeed, not send
messages larger than 200 bytes.

But the fact that the SPI controller's max_message_size does not
necessarily mean that we cannot send messages larger than that.
Notably, if the SPI master special-cases the transfers with cs_change
and treats every chip select toggling as an entirely new transaction,
then a SPI message can easily exceed that limit. So there is a
temptation to ignore the controller's reported max_message_size when
using cs_change = true in non-final transfers.

But that can lead to false conclusions. As Mark points out, the SPI
controller might have a different kind of limitation with the max
message size, that has nothing at all to do with how long it can keep
the chip select asserted.
For example, that might be the case if the device is able to offload the
chip select changes to the hardware as part of the data stream, and it
packs the entire stream of commands+data (corresponding to a SPI
message) into a single DMA transfer that is itself limited in size.

So the only thing we can do is avoid ambiguity by not using cs_change at
all. Instead of sending a single spi_message, we now send multiple SPI
messages as follows:

                  spi_message 0                 spi_message 1                       spi_message n
           ____________________________   ___________________________        _____________________________
          /                            \ /                           \      /                             \
          +-------------+---------------+-------------+---------------+ ... +-------------+---------------+
          | hdr_xfer[0] | chunk_xfer[0] | hdr_xfer[1] | chunk_xfer[1] |     | hdr_xfer[n] | chunk_xfer[n] |
          +-------------+---------------+-------------+---------------+ ... +-------------+---------------+
cs_change      false          true           false           true                false          false

           ____________________________  _____________________________       _____________________________
CS line __/                            \/                             \ ... /                             \__

which is clearer because the max_message_size limit is now easier to
enforce. What is transmitted on the wire stays, of course, the same.

Additionally, because we send no more than 2 transfers at a time, we now
avoid dynamic memory allocation too, which might be seen as an
improvement by some.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Free skb->cb usage in core driver and let device drivers decide to
use or not. The reason having a DSA_SKB_CB(skb)->clone was because
dsa_skb_tx_timestamp() which may set the clone pointer was called
before p->xmit() which would use the clone if any, and the device
driver has no way to initialize the clone pointer.

This patch just put memset(skb->cb, 0, sizeof(skb->cb)) at beginning
of dsa_slave_xmit(). Some new features in the future, like one-step
timestamp may need more bytes of skb->cb to use in
dsa_skb_tx_timestamp(), and p->xmit().
Signed-off-by: NYangbo Lu <yangbo.lu@nxp.com>
Acked-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It was a waste to clone skb directly in dsa_skb_tx_timestamp().
For one-step timestamping, a clone was not needed. For any failure of
port_txtstamp (this may usually happen), the skb clone had to be freed.

So this patch moves skb cloning for tx timestamp out of dsa core, and
let drivers clone skb in port_txtstamp if they really need.
Signed-off-by: NYangbo Lu <yangbo.lu@nxp.com>
Tested-by: NKurt Kanzenbach <kurt@linutronix.de>
Acked-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move ptp_classify_raw out of dsa core driver for handling tx
timestamp request. Let device drivers do this if they want.
Not all drivers want to limit tx timestamping for only PTP
packet.
Signed-off-by: NYangbo Lu <yangbo.lu@nxp.com>
Tested-by: NKurt Kanzenbach <kurt@linutronix.de>
Acked-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit e9bf9694.

The topic of the reverted patch is the support for switches with global
VLAN filtering, added by commit 061f6a50 ("net: dsa: Add
ndo_vlan_rx_{add, kill}_vid implementation"). Be there a switch with 4
ports swp0 -> swp3, and the following setup:

ip link add br0 type bridge vlan_filtering 1
ip link set swp0 master br0
ip link set swp1 master br0

What would happen with VLAN-tagged traffic received on standalone ports
swp2 and swp3? Well, it would get dropped, were it not for the
.ndo_vlan_rx_add_vid and .ndo_vlan_rx_kill_vid implementations (called
from vlan_vid_add and vlan_vid_del respectively). Basically, for DSA
switches where VLAN filtering is a global attribute, we enforce the
standalone ports to have 'rx-vlan-filter: off [fixed]' in their ethtool
features, which lets the user know that all VLAN-tagged packets that are
not explicitly added in the RX filtering list are dropped.

As for the sja1105 driver, at the time of the reverted patch, it was
operating in a pretty handicapped mode when it had ports under a bridge
with vlan_filtering=1. Specifically, it was unable to terminate traffic
through the CPU port (for further explanation see "Traffic support" in
Documentation/networking/dsa/sja1105.rst).

However, since then, the sja1105 driver has made considerable progress,
and that limitation is no longer as severe now. Specifically, since
commit 2cafa72e ("net: dsa: sja1105: add a new
best_effort_vlan_filtering devlink parameter"), the driver is able to
perform CPU termination even when some ports are under bridges with
vlan_filtering=1. Then, since commit 8841f6e6 ("net: dsa: sja1105:
make devlink property best_effort_vlan_filtering true by default"), this
even became the default operating mode.

So we can now take advantage of the logic in the DSA core.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The return value 'rc' maybe overwrite to 0 in the flow_action_for_each
loop, the error code from the offload not support error handling will
not set. This commit fix it to return -EOPNOTSUPP.

Fixes: 6a56e199 ("flow_offload: reject configuration of packet-per-second policing in offload drivers")
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A follow-up patch will allow users to configures packet-per-second policing
in the software datapath. In preparation for this, teach all drivers that
support offload of the policer action to reject such configuration as
currently none of them support it.
Signed-off-by: NBaowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NLouis Peens <louis.peens@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the blamed patch I managed to introduce a bug while moving code
around: the same logic is applied to the ucast_egress_floods and
bcast_egress_floods variables both on the "if" and the "else" branches.

This is clearly an unintended change compared to how the code used to be
prior to that bugfix, so restore it.

Fixes: 7f7ccdea ("net: dsa: sja1105: fix leakage of flooded frames outside bridging domain")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When using MLO_AN_PHY or MLO_AN_FIXED, the MII_BMCR of the SGMII PCS is
read before resetting the switch so it can be reprogrammed afterwards.
This works for the speeds of 1Gbps and 100Mbps, but not for 10Mbps,
because SPEED_10 is actually 0, so AND-ing anything with 0 is false,
therefore that last branch is dead code.

Do what others do (genphy_read_status_fixed, phy_mii_ioctl) and just
remove the check for SPEED_10, let it fall into the default case.

Fixes: ffe10e67 ("net: dsa: sja1105: Add support for the SGMII port")
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sja1105_unpack() takes a "const void *buf" as its first parameter, so
there is no need to cast away the "const" of the "buf" variable before
calling it.

Drop the cast, as it prevents the compiler performing some checks.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NVladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20210223112003.2223332-1-geert+renesas@glider.beSigned-off-by: NJakub Kicinski <kuba@kernel.org>