net: dsa: sja1105: offload the Credit-Based Shaper qdisc

SJA1105, being AVB/TSN switches, provide hardware assist for the
Credit-Based Shaper as described in the IEEE 8021Q-2018 document.

First gen

net: dsa: sja1105: offload the Credit-Based Shaper qdisc

SJA1105, being AVB/TSN switches, provide hardware assist for the
Credit-Based Shaper as described in the IEEE 8021Q-2018 document.

First generation has 10 shapers, freely assignable to any of the 4
external ports and 8 traffic classes, and second generation has 16
shapers.

The Credit-Based Shaper tables are accessed through the dynamic
reconfiguration interface, so we have to restore them manually after a
switch reset. The tables are backed up by the static config only on
P/Q/R/S, and we don't want to add custom code only for that family,
since the procedure that is in place now works for both.

Tested with the following commands:

data_rate_kbps=67000
port_transmit_rate_kbps=1000000
idleslope=$data_rate_kbps
sendslope=$(($idleslope - $port_transmit_rate_kbps))
locredit=$((-0x80000000))
hicredit=$((0x7fffffff))
tc qdisc add dev swp2 root handle 1: mqprio hw 0 num_tc 8 \
map 0 1 2 3 4 5 6 7 \
queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7
tc qdisc replace dev swp2 parent 1:1 cbs \
idleslope $idleslope \
sendslope $sendslope \
hicredit $hicredit \
locredit $locredit \
offload 1

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: implement a common frame memory partitioning function

There are 2 different features that require some reserved frame memory
space: VLAN retagging and virtual links. Create a cent

net: dsa: sja1105: implement a common frame memory partitioning function

There are 2 different features that require some reserved frame memory
space: VLAN retagging and virtual links. Create a central function that
modifies the static config and ensures frame memory is never
overcommitted.

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

show more ...

net: dsa: sja1105: add packing ops for the Retagging Table

The Retagging Table is an optional feature that allows the switch to
match frames against a {ingress port, egress port, vid} rule and chang

net: dsa: sja1105: add packing ops for the Retagging Table

The Retagging Table is an optional feature that allows the switch to
match frames against a {ingress port, egress port, vid} rule and change
their VLAN ID. The retagged frames are by default clones of the original
ones (since the hardware-foreseen use case was to mirror traffic for
debugging purposes and to tag it with a special VLAN for this purpose),
but we can force the original frames to be dropped by removing the
pre-retagging VLAN from the port membership list of the egress port.

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

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net: dsa: sja1105: add a new best_effort_vlan_filtering devlink parameter

This devlink parameter enables the handling of DSA tags when enslaved to
a bridge with vlan_filtering=1. There are very good

net: dsa: sja1105: add a new best_effort_vlan_filtering devlink parameter

This devlink parameter enables the handling of DSA tags when enslaved to
a bridge with vlan_filtering=1. There are very good reasons to want
this, but there are also very good reasons for not enabling it by
default. So a devlink param named best_effort_vlan_filtering, currently
driver-specific and exported only by sja1105, is used to configure this.

In practice, this is perhaps the way that most users are going to use
the switch in. It assumes that no more than 7 VLANs are needed per port.

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

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net: dsa: sja1105: prepare tagger for handling DSA tags and VLAN simultaneously

In VLAN-unaware mode, sja1105 uses VLAN tags with a custom TPID of
0xdadb. While in the yet-to-be introduced best_effo

net: dsa: sja1105: prepare tagger for handling DSA tags and VLAN simultaneously

In VLAN-unaware mode, sja1105 uses VLAN tags with a custom TPID of
0xdadb. While in the yet-to-be introduced best_effort_vlan_filtering
mode, it needs to work with normal VLAN TPID values.

A complication arises when we must transmit a VLAN-tagged packet to the
switch when it's in VLAN-aware mode. We need to construct a packet with
2 VLAN tags, and the switch will use the outer header for routing and
pop it on egress. But sadly, here the 2 hardware generations don't
behave the same:

- E/T switches won't pop an ETH_P_8021AD tag on egress, it seems
(packets will remain double-tagged).
- P/Q/R/S switches will drop a packet with 2 ETH_P_8021Q tags (it looks
like it tries to prevent VLAN hopping).

But looks like the reverse is also true:

- E/T switches have no problem popping the outer tag from packets with
2 ETH_P_8021Q tags.
- P/Q/R/S will have no problem popping a single tag even if that is
ETH_P_8021AD.

So it is clear that if we want the hardware to work with dsa_8021q
tagging in VLAN-aware mode, we need to send different TPIDs depending on
revision. Keep that information in priv->info->qinq_tpid.

The per-port tagger structure will hold an xmit_tpid value that depends
not only upon the qinq_tpid, but also upon the VLAN awareness state
itself (in case we must transmit using 0xdadb).

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

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net: dsa: sja1105: save/restore VLANs using a delta commit method

Managing the VLAN table that is present in hardware will become very
difficult once we add a third operating state
(best_effort_vlan

net: dsa: sja1105: save/restore VLANs using a delta commit method

Managing the VLAN table that is present in hardware will become very
difficult once we add a third operating state
(best_effort_vlan_filtering). That is because correct cleanup (not too
little, not too much) becomes virtually impossible, when VLANs can be
added from the bridge layer, from dsa_8021q for basic tagging, for
cross-chip bridging, as well as retagging rules for sub-VLANs and
cross-chip sub-VLANs. So we need to rethink VLAN interaction with the
switch in a more scalable way.

In preparation for that, use the priv->expect_dsa_8021q boolean to
classify any VLAN request received through .port_vlan_add or
.port_vlan_del towards either one of 2 internal lists: bridge VLANs and
dsa_8021q VLANs.

Then, implement a central sja1105_build_vlan_table method that creates a
VLAN configuration from scratch based on the 2 lists of VLANs kept by
the driver, and based on the VLAN awareness state. Currently, if we are
VLAN-unaware, install the dsa_8021q VLANs, otherwise the bridge VLANs.

Then, implement a delta commit procedure that identifies which VLANs
from this new configuration are actually different from the config
previously committed to hardware. We apply the delta through the dynamic
configuration interface (we don't reset the switch). The result is that
the hardware should see the exact sequence of operations as before this
patch.

This also helps remove the "br" argument passed to
dsa_8021q_crosschip_bridge_join, which it was only using to figure out
whether it should commit the configuration back to us or not, based on
the VLAN awareness state of the bridge. We can simplify that, by always
allowing those VLANs inside of our dsa_8021q_vlans list, and committing
those to hardware when necessary.

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

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net: dsa: sja1105: deny alterations of dsa_8021q VLANs from the bridge

At the moment, this can never happen. The 2 modes that we operate in do
not permit that:

- SJA1105_VLAN_UNAWARE: we are guard

net: dsa: sja1105: deny alterations of dsa_8021q VLANs from the bridge

At the moment, this can never happen. The 2 modes that we operate in do
not permit that:

- SJA1105_VLAN_UNAWARE: we are guarded from bridge VLANs added by the
user by the DSA core. We will later lift this restriction by setting
ds->vlan_bridge_vtu = true, and that is where we'll need it.

- SJA1105_VLAN_FILTERING_FULL: in this mode, dsa_8021q configuration is
disabled. So the user is free to add these VLANs in the 1024-3071
range.

The reason for the patch is that we'll introduce a third VLAN awareness
state, where both dsa_8021q as well as the bridge are going to call our
.port_vlan_add and .port_vlan_del methods.

For that, we need a good way to discriminate between the 2. The easiest
(and less intrusive way for upper layers) is to recognize the fact that
dsa_8021q configurations are always driven by our driver - we _know_
when a .port_vlan_add method will be called from dsa_8021q because _we_
initiated it.

So introduce an expect_dsa_8021q boolean which is only used, at the
moment, for blacklisting VLANs in range 1024-3071 in the modes when
dsa_8021q is active.

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

show more ...

net: dsa: sja1105: keep the VLAN awareness state in a driver variable

Soon we'll add a third operating mode to the driver. Introduce a
vlan_state to make things more easy to manage, and use it where

net: dsa: sja1105: keep the VLAN awareness state in a driver variable

Soon we'll add a third operating mode to the driver. Introduce a
vlan_state to make things more easy to manage, and use it where
applicable.

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

show more ...

net: dsa: sja1105: implement cross-chip bridging operations

sja1105 uses dsa_8021q for DSA tagging, a format which is VLAN at heart
and which is compatible with cascading. A complete description of

net: dsa: sja1105: implement cross-chip bridging operations

sja1105 uses dsa_8021q for DSA tagging, a format which is VLAN at heart
and which is compatible with cascading. A complete description of this
tagging format is in net/dsa/tag_8021q.c, but a quick summary is that
each external-facing port tags incoming frames with a unique pvid, and
this special VLAN is transmitted as tagged towards the inside of the
system, and as untagged towards the exterior. The tag encodes the switch
id and the source port index.

This means that cross-chip bridging for dsa_8021q only entails adding
the dsa_8021q pvids of one switch to the RX filter of the other
switches. Everything else falls naturally into place, as long as the
bottom-end of ports (the leaves in the tree) is comprised exclusively of
dsa_8021q-compatible (i.e. sja1105 switches). Otherwise, there would be
a chance that a front-panel switch transmits a packet tagged with a
dsa_8021q header, header which it wouldn't be able to remove, and which
would hence "leak" out.

The only use case I tested (due to lack of board availability) was when
the sja1105 switches are part of disjoint trees (however, this doesn't
change the fact that multiple sja1105 switches still need unique switch
identifiers in such a system). But in principle, even "true" single-tree
setups (with DSA links) should work just as fine, except for a small
change which I can't test: dsa_towards_port should be used instead of
dsa_upstream_port (I made the assumption that the routing port that any
sja1105 should use towards its neighbours is the CPU port. That might
not hold true in other setups).

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: dsa: sja1105: implement tc-gate using time-triggered virtual links

Restrict the TTEthernet hardware support on this switch to operate as
closely as possible to IEEE 802.1Qci as possible. This m

net: dsa: sja1105: implement tc-gate using time-triggered virtual links

Restrict the TTEthernet hardware support on this switch to operate as
closely as possible to IEEE 802.1Qci as possible. This means that it can
perform PTP-time-based ingress admission control on streams identified
by {DMAC, VID, PCP}, which is useful when trying to ensure the
determinism of traffic scheduled via IEEE 802.1Qbv.

The oddity comes from the fact that in hardware (and in TTEthernet at
large), virtual links always need a full-blown action, including not
only the type of policing, but also the list of destination ports. So in
practice, a single tc-gate action will result in all packets getting
dropped. Additional actions (either "trap" or "redirect") need to be
specified in the same filter rule such that the conforming packets are
actually forwarded somewhere.

Apart from the VL Lookup, Policing and Forwarding tables which need to
be programmed for each flow (virtual link), the Schedule engine also
needs to be told to open/close the admission gates for each individual
virtual link. A fairly accurate (and detailed) description of how that
works is already present in sja1105_tas.c, since it is already used to
trigger the egress gates for the tc-taprio offload (IEEE 802.1Qbv). Key
point here, we remember that the schedule engine supports 8
"subschedules" (execution threads that iterate through the global
schedule in parallel, and that no 2 hardware threads must execute a
schedule entry at the same time). For tc-taprio, each egress port used
one of these 8 subschedules, leaving a total of 4 subschedules unused.
In principle we could have allocated 1 subschedule for the tc-gate
offload of each ingress port, but actually the schedules of all virtual
links installed on each ingress port would have needed to be merged
together, before they could have been programmed to hardware. So
simplify our life and just merge the entire tc-gate configuration, for
all virtual links on all ingress ports, into a single subschedule. Be
sure to check that against the usual hardware scheduling conflicts, and
program it to hardware alongside any tc-taprio subschedule that may be
present.

The following scenarios were tested:

1. Quantitative testing:

tc qdisc add dev swp2 clsact
tc filter add dev swp2 ingress flower skip_sw \
dst_mac 42:be:24:9b:76:20 \
action gate index 1 base-time 0 \
sched-entry OPEN 1200 -1 -1 \
sched-entry CLOSE 1200 -1 -1 \
action trap

ping 192.168.1.2 -f
PING 192.168.1.2 (192.168.1.2) 56(84) bytes of data.
.............................
--- 192.168.1.2 ping statistics ---
948 packets transmitted, 467 received, 50.7384% packet loss, time 9671ms

2. Qualitative testing (with a phase-aligned schedule - the clocks are
synchronized by ptp4l, not shown here):

Receiver (sja1105):

tc qdisc add dev swp2 clsact
now=$(phc_ctl /dev/ptp1 get | awk '/clock time is/ {print $5}') && \
sec=$(echo $now | awk -F. '{print $1}') && \
base_time="$(((sec + 2) * 1000000000))" && \
echo "base time ${base_time}"
tc filter add dev swp2 ingress flower skip_sw \
dst_mac 42:be:24:9b:76:20 \
action gate base-time ${base_time} \
sched-entry OPEN 60000 -1 -1 \
sched-entry CLOSE 40000 -1 -1 \
action trap

Sender (enetc):
now=$(phc_ctl /dev/ptp0 get | awk '/clock time is/ {print $5}') && \
sec=$(echo $now | awk -F. '{print $1}') && \
base_time="$(((sec + 2) * 1000000000))" && \
echo "base time ${base_time}"
tc qdisc add dev eno0 parent root taprio \
num_tc 8 \
map 0 1 2 3 4 5 6 7 \
queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
base-time ${base_time} \
sched-entry S 01 50000 \
sched-entry S 00 50000 \
flags 2

ping -A 192.168.1.1
PING 192.168.1.1 (192.168.1.1): 56 data bytes
...
^C
--- 192.168.1.1 ping statistics ---
1425 packets transmitted, 1424 packets received, 0% packet loss
round-trip min/avg/max = 0.322/0.361/0.990 ms

And just for comparison, with the tc-taprio schedule deleted:

ping -A 192.168.1.1
PING 192.168.1.1 (192.168.1.1): 56 data bytes
...
^C
--- 192.168.1.1 ping statistics ---
33 packets transmitted, 19 packets received, 42% packet loss
round-trip min/avg/max = 0.336/0.464/0.597 ms

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: support flow-based redirection via virtual links

Implement tc-flower offloads for redirect, trap and drop using
non-critical virtual links.

Commands which were tested to work are

net: dsa: sja1105: support flow-based redirection via virtual links

Implement tc-flower offloads for redirect, trap and drop using
non-critical virtual links.

Commands which were tested to work are:

# Send frames received on swp2 with a DA of 42:be:24:9b:76:20 to the
# CPU and to swp3. This type of key (DA only) when the port's VLAN
# awareness state is off.
tc qdisc add dev swp2 clsact
tc filter add dev swp2 ingress flower skip_sw dst_mac 42:be:24:9b:76:20 \
action mirred egress redirect dev swp3 \
action trap

# Drop frames received on swp2 with a DA of 42:be:24:9b:76:20, a VID
# of 100 and a PCP of 0.
tc filter add dev swp2 ingress protocol 802.1Q flower skip_sw \
dst_mac 42:be:24:9b:76:20 vlan_id 100 vlan_prio 0 action drop

Under the hood, all rules match on DMAC, VID and PCP, but when VLAN
filtering is disabled, those are set internally by the driver to the
port-based defaults. Because we would be put in an awkward situation if
the user were to change the VLAN filtering state while there are active
rules (packets would no longer match on the specified keys), we simply
deny changing vlan_filtering unless the list of flows offloaded via
virtual links is empty. Then the user can re-add new rules.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: make room for virtual link parsing in flower offload

Virtual links are a sja1105 hardware concept of executing various flow
actions based on a key extracted from the frame's DMAC,

net: dsa: sja1105: make room for virtual link parsing in flower offload

Virtual links are a sja1105 hardware concept of executing various flow
actions based on a key extracted from the frame's DMAC, VID and PCP.

Currently the tc-flower offload code supports only parsing the DMAC if
that is the broadcast MAC address, and the VLAN PCP. Extract the key
parsing logic from the L2 policers functionality and move it into its
own function, after adding extra logic for matching on any DMAC and VID.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: add static tables for virtual links

This patch adds the register definitions for the:
- VL Lookup Table
- VL Policing Table
- VL Forwarding Table
- VL Forwarding Parameters Table

net: dsa: sja1105: add static tables for virtual links

This patch adds the register definitions for the:
- VL Lookup Table
- VL Policing Table
- VL Forwarding Table
- VL Forwarding Parameters Table

These are needed in order to perform TTEthernet operations: QoS
classification, flow-based policing and/or frame redirecting with the
switch.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: enable internal pull-down for RX_DV/CRS_DV/RX_CTL and RX_ER

Some boards do not have the RX_ER MII signal connected. Normally in such
situation, those pins would be grounded, but t

net: dsa: sja1105: enable internal pull-down for RX_DV/CRS_DV/RX_CTL and RX_ER

Some boards do not have the RX_ER MII signal connected. Normally in such
situation, those pins would be grounded, but then again, some boards
left it electrically floating.

When sending traffic to those switch ports, one can see that the
N_SOFERR statistics counter is incrementing once per each packet. The
user manual states for this counter that it may count the number of
frames "that have the MII error input being asserted prior to or
up to the SOF delimiter byte". So the switch MAC is sampling an
electrically floating signal, and preventing proper traffic reception
because of that.

As a workaround, enable the internal weak pull-downs on the input pads
for the MII control signals. This way, a floating signal would be
internally tied to ground.

The logic levels of signals which _are_ externally driven should not be
bothered by this 40-50 KOhm internal resistor. So it is not an issue to
enable the internal pull-down unconditionally, irrespective of PHY
interface type (MII, RMII, RGMII, SGMII) and of board layout.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: add broadcast and per-traffic class policers

This patch adds complete support for manipulating the L2 Policing Tables
from this switch. There are 45 table entries, one entry per e

net: dsa: sja1105: add broadcast and per-traffic class policers

This patch adds complete support for manipulating the L2 Policing Tables
from this switch. There are 45 table entries, one entry per each port
and traffic class, and one dedicated entry for broadcast traffic for
each ingress port.

Policing entries are shareable, and we use this functionality to support
shared block filters.

We are modeling broadcast policers as simple tc-flower matches on
dst_mac. As for the traffic class policers, the switch only deduces the
traffic class from the VLAN PCP field, so it makes sense to model this
as a tc-flower match on vlan_prio.

How to limit broadcast traffic coming from all front-panel ports to a
cumulated total of 10 Mbit/s:

tc qdisc add dev sw0p0 ingress_block 1 clsact
tc qdisc add dev sw0p1 ingress_block 1 clsact
tc qdisc add dev sw0p2 ingress_block 1 clsact
tc qdisc add dev sw0p3 ingress_block 1 clsact
tc filter add block 1 flower skip_sw dst_mac ff:ff:ff:ff:ff:ff \
action police rate 10mbit burst 64k

How to limit traffic with VLAN PCP 0 (also includes untagged traffic) to
100 Mbit/s on port 0 only:

tc filter add dev sw0p0 ingress protocol 802.1Q flower skip_sw \
vlan_prio 0 action police rate 100mbit burst 64k

The broadcast, VLAN PCP and port policers are compatible with one
another (can be installed at the same time on a port).

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: show more ethtool statistics counters for P/Q/R/S

It looks like the P/Q/R/S series supports some more counters,
generically named "Ethernet statistics counter", which we were not

net: dsa: sja1105: show more ethtool statistics counters for P/Q/R/S

It looks like the P/Q/R/S series supports some more counters,
generically named "Ethernet statistics counter", which we were not
printing. Add them.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: implement the port MTU callbacks

On this switch, the frame length enforcements are performed by the
ingress policers. There are 2 types of those: regular L2 (also called
best-effo

net: dsa: sja1105: implement the port MTU callbacks

On this switch, the frame length enforcements are performed by the
ingress policers. There are 2 types of those: regular L2 (also called
best-effort) and Virtual Link policers (an ARINC664/AFDX concept for
defining L2 streams with certain QoS abilities). To avoid future
confusion, I prefer to call the reset reason "Best-effort policers",
even though the VL policers are not yet supported.

We also need to change the setup of the initial static config, such that
DSA calls to .change_mtu (which are expensive) become no-ops and don't
reset the switch 5 times.

A driver-level decision is to unconditionally allow single VLAN-tagged
traffic on all ports. The CPU port must accept an additional VLAN header
for the DSA tag, which is again a driver-level decision.

The policers actually count bytes not only from the SDU, but also from
the Ethernet header and FCS, so those need to be accounted for as well.

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

show more ...

net: dsa: sja1105: configure the PTP_CLK pin as EXT_TS or PER_OUT

The SJA1105 switch family has a PTP_CLK pin which emits a signal with
fixed 50% duty cycle, but variable frequency and programmable

net: dsa: sja1105: configure the PTP_CLK pin as EXT_TS or PER_OUT

The SJA1105 switch family has a PTP_CLK pin which emits a signal with
fixed 50% duty cycle, but variable frequency and programmable start time.

On the second generation (P/Q/R/S) switches, this pin supports even more
functionality. The use case described by the hardware documents talks
about synchronization via oneshot pulses: given 2 sja1105 switches,
arbitrarily designated as a master and a slave, the master emits a
single pulse on PTP_CLK, while the slave is configured to timestamp this
pulse received on its PTP_CLK pin (which must obviously be configured as
input). The difference between the timestamps then exactly becomes the
slave offset to the master.

The only trouble with the above is that the hardware is very much tied
into this use case only, and not very generic beyond that:
- When emitting a oneshot pulse, instead of being told when to emit it,
the switch just does it "now" and tells you later what time it was,
via the PTPSYNCTS register. [ Incidentally, this is the same register
that the slave uses to collect the ext_ts timestamp from, too. ]
- On the sync slave, there is no interrupt mechanism on reception of a
new extts, and no FIFO to buffer them, because in the foreseen use
case, software is in control of both the master and the slave pins,
so it "knows" when there's something to collect.

These 2 problems mean that:
- We don't support (at least yet) the quirky oneshot mode exposed by
the hardware, just normal periodic output.
- We abuse the hardware a little bit when we expose generic extts.
Because there's no interrupt mechanism, we need to poll at double the
frequency we expect to receive a pulse. Currently that means a
non-configurable "twice a second".

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: make the AVB table dynamically reconfigurable

The AVB table contains the CAS_MASTER field (to be added in the next
patch) which decides the direction of the PTP_CLK pin.

Reconfig

net: dsa: sja1105: make the AVB table dynamically reconfigurable

The AVB table contains the CAS_MASTER field (to be added in the next
patch) which decides the direction of the PTP_CLK pin.

Reconfiguring this field dynamically is highly preferable to having to
reset the switch and upload a new static configuration, so we add
support for exactly that.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: Add support for the SGMII port

SJA1105 switches R and S have one SerDes port with an 802.3z
quasi-compatible PCS, hardwired on port 4. The other ports are still
MII/RMII/RGMII. Th

net: dsa: sja1105: Add support for the SGMII port

SJA1105 switches R and S have one SerDes port with an 802.3z
quasi-compatible PCS, hardwired on port 4. The other ports are still
MII/RMII/RGMII. The PCS performs rate adaptation to lower link speeds;
the MAC on this port is hardwired at gigabit. Only full duplex is
supported.

The SGMII port can be configured as part of the static config tables, as
well as through a dedicated SPI address region for its pseudo-clause-22
registers. However it looks like the static configuration is not
able to change some out-of-reset values (like the value of MII_BMCR), so
at the end of the day, having code for it is utterly pointless. We are
just going to use the pseudo-C22 interface.

Because the PCS gets reset when the switch resets, we have to add even
more restoration logic to sja1105_static_config_reload, otherwise the
SGMII port breaks after operations such as enabling PTP timestamping
which require a switch reset.

>From PHYLINK perspective, the switch supports *only* SGMII (it doesn't
support 1000Base-X). It also doesn't expose access to the raw config
word for in-band AN in registers MII_ADV/MII_LPA.
It is able to work in the following modes:
- Forced speed
- SGMII in-band AN slave (speed received from PHY)
- SGMII in-band AN master (acting as a PHY)

The latter mode is not supported by this patch. It is even unclear to me
how that would be described. There is some code for it left in the
patch, but 'an_master' is always passed as false.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: Simplify reset handling

We don't really need 10k species of reset. Remove everything except cold
reset which is what is actually used. Too bad the hardware designers
couldn't agre

net: dsa: sja1105: Simplify reset handling

We don't really need 10k species of reset. Remove everything except cold
reset which is what is actually used. Too bad the hardware designers
couldn't agree to use the same bit field for rev 1 and rev 2, so the
(*reset_cmd) function pointer is there to stay.

However let's simplify the prototype and give it a struct dsa_switch (we
want to avoid forward-declarations of structures, in this case struct
sja1105_private, wherever we can).

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: Implement state machine for TAS with PTP clock source

Tested using the following bash script and the tc from iproute2-next:

#!/bin/bash

set -e -u -o pipefail

NSEC_PER_SEC="1

net: dsa: sja1105: Implement state machine for TAS with PTP clock source

Tested using the following bash script and the tc from iproute2-next:

#!/bin/bash

set -e -u -o pipefail

NSEC_PER_SEC="1000000000"

gatemask() {
local tc_list="$1"
local mask=0

for tc in ${tc_list}; do
mask=$((${mask} | (1 << ${tc})))
done

printf "%02x" ${mask}
}

if ! systemctl is-active --quiet ptp4l; then
echo "Please start the ptp4l service"
exit
fi

now=$(phc_ctl /dev/ptp1 get | gawk '/clock time is/ { print $5; }')
# Phase-align the base time to the start of the next second.
sec=$(echo "${now}" | gawk -F. '{ print $1; }')
base_time="$(((${sec} + 1) * ${NSEC_PER_SEC}))"

tc qdisc add dev swp5 parent root handle 100 taprio \
num_tc 8 \
map 0 1 2 3 5 6 7 \
queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
base-time ${base_time} \
sched-entry S $(gatemask 7) 100000 \
sched-entry S $(gatemask "0 1 2 3 4 5 6") 400000 \
clockid CLOCK_TAI flags 2

The "state machine" is a workqueue invoked after each manipulation
command on the PTP clock (reset, adjust time, set time, adjust
frequency) which checks over the state of the time-aware scheduler.
So it is not monitored periodically, only in reaction to a PTP command
typically triggered from a userspace daemon (linuxptp). Otherwise there
is no reason for things to go wrong.

Now that the timecounter/cyclecounter has been replaced with hardware
operations on the PTP clock, the TAS Kconfig now depends upon PTP and
the standalone clocksource operating mode has been removed.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: Make the PTP command read-write

The PTPSTRTSCH and PTPSTOPSCH bits are actually readable and indicate
whether the time-aware scheduler is running or not. We will be using
that for

net: dsa: sja1105: Make the PTP command read-write

The PTPSTRTSCH and PTPSTOPSCH bits are actually readable and indicate
whether the time-aware scheduler is running or not. We will be using
that for monitoring the scheduler in the next patch, so refactor the PTP
command API in order to allow that.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: dsa: sja1105: Print the reset reason

Sometimes it can be quite opaque even for me why the driver decided to
reset the switch. So instead of adding dump_stack() calls each time for
debugging, ju

net: dsa: sja1105: Print the reset reason

Sometimes it can be quite opaque even for me why the driver decided to
reset the switch. So instead of adding dump_stack() calls each time for
debugging, just add a reset reason to sja1105_static_config_reload
calls which gets printed to the console.

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

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net: dsa: sja1105: Implement the .gettimex64 system call for PTP

Through the PTP_SYS_OFFSET_EXTENDED ioctl, it is possible for userspace
applications (i.e. phc2sys) to compensate for the delays incu

net: dsa: sja1105: Implement the .gettimex64 system call for PTP

Through the PTP_SYS_OFFSET_EXTENDED ioctl, it is possible for userspace
applications (i.e. phc2sys) to compensate for the delays incurred while
reading the PHC's time.

The task itself of taking the software timestamp is delegated to the SPI
subsystem, through the newly introduced API in struct spi_transfer. The
goal is to cross-timestamp I/O operations on the switch's PTP clock with
values in the local system clock (CLOCK_REALTIME). For that we need to
understand a bit of the hardware internals.

The 'read PTP time' message is a 12 byte structure, first 4 bytes of
which represent the SPI header, and the last 8 bytes represent the
64-bit PTP time. The switch itself starts processing the command
immediately after receiving the last bit of the address, i.e. at the
middle of byte 3 (last byte of header). The PTP time is shadowed to a
buffer register in the switch, and retrieved atomically during the
subsequent SPI frames.

A similar thing goes on for the 'write PTP time' message, although in
that case the switch waits until the 64-bit PTP time becomes fully
available before taking any action. So the byte that needs to be
software-timestamped is byte 11 (last) of the transfer.

The patch creates a common (and local) sja1105_xfer implementation for
the SPI I/O, and offers 3 front-ends:

- sja1105_xfer_u32 and sja1105_xfer_u64: these are capable of optionally
requesting a PTP timestamp

- sja1105_xfer_buf: this is for large transfers (e.g. the static config
buffer) and other misc data, and there is no point in giving
timestamping capabilities to this.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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