This qdisc offload is the closest thing to what the SJA1105 supports in
hardware for time-based egress shaping. The switch core really is built
around SAE AS6802/TTEthernet (a TTTech standard) but can be made to
operate similarly to IEEE 802.1Qbv with some constraints:
- The gate control list is a global list for all ports. There are 8
execution threads that iterate through this global list in parallel.
I don't know why 8, there are only 4 front-panel ports.
- Care must be taken by the user to make sure that two execution threads
never get to execute a GCL entry simultaneously. I created a O(n^4)
checker for this hardware limitation, prior to accepting a taprio
offload configuration as valid.
- The spec says that if a GCL entry's interval is shorter than the frame
length, you shouldn't send it (and end up in head-of-line blocking).
Well, this switch does anyway.
- The switch has no concept of ADMIN and OPER configurations. Because
it's so simple, the TAS settings are loaded through the static config
tables interface, so there isn't even place for any discussion about
'graceful switchover between ADMIN and OPER'. You just reset the
switch and upload a new OPER config.
- The switch accepts multiple time sources for the gate events. Right
now I am using the standalone clock source as opposed to PTP. So the
base time parameter doesn't really do much. Support for the PTP clock
source will be added in a future series.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As per the DT phy-mode specification, RGMII delays are applied by the
MAC when there is no PHY present on the link.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The pad_mii_tx registers point to the same memory region but were
unused. So convert to using these for RGMII I/O cell configuration, as
they bear a shorter name.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This will be used to stop egress traffic in .phylink_mac_link_up.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This will be used to keep state for RX timestamping. It is global
because the switch serializes timestampable and meta frames when
trapping them towards the CPU port (lower port indices have higher
priority) and therefore having one state machine per port would create
unnecessary complications.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On TX, timestamping is performed synchronously from the
port_deferred_xmit worker thread.
In management routes, the switch is requested to take egress timestamps
(again partial), which are reconstructed and appended to a clone of the
skb that was just sent. The cloning is done by DSA and we retrieve the
pointer from the structure that DSA keeps in skb->cb.
Then these clones are enqueued to the socket's error queue for
application-level processing.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The design of this PHC driver is influenced by the switch's behavior
w.r.t. timestamping. It exposes two PTP counters, one free-running
(PTPTSCLK) and the other offset- and frequency-corrected in hardware
through PTPCLKVAL, PTPCLKADD and PTPCLKRATE. The MACs can sample either
of these for frame timestamps.
However, the user manual warns that taking timestamps based on the
corrected clock is less than useful, as the switch can deliver corrupted
timestamps in a variety of circumstances.
Therefore, this PHC uses the free-running PTPTSCLK together with a
timecounter/cyclecounter structure that translates it into a software
time domain. Thus, the settime/adjtime and adjfine callbacks are
hardware no-ops.
The timestamps (introduced in a further patch) will also be translated
to the correct time domain before being handed over to the userspace PTP
stack.
The introduction of a second set of PHC operations that operate on the
hardware PTPCLKVAL/PTPCLKADD/PTPCLKRATE in the future is somewhat
unavoidable, as the TTEthernet core uses the corrected PTP time domain.
However, the free-running counter + timecounter structure combination
will suffice for now, as the resulting timestamps yield a sub-50 ns
synchronization offset in steady state using linuxptp.
For this patch, in absence of frame timestamping, the operations of the
switch PHC were tested by syncing it to the system time as a local slave
clock with:
phc2sys -s CLOCK_REALTIME -c swp2 -O 0 -m -S 0.01
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds support for manipulating the L2 forwarding database (dump,
add, delete) for the second generation of NXP SJA1105 switches.
At the moment only FDB entries installed statically through 'bridge fdb'
are visible in the dump callback - the dynamically learned ones are
still under investigation.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The DSA callbacks were written with the E/T (first generation) in mind,
which is quite different.
For P/Q/R/S completely new implementations need to be provided, which
are held as function pointers in the priv->info structure. We are
taking a slightly roundabout way for this (a function from
sja1105_main.c reads a structure defined in sja1105_spi.c that
points to a function defined in sja1105_main.c), but it is what it is.
The FDB dump callback works for both families, hence no function pointer
for that.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to support this, we are creating a make-shift switch tag out of
a VLAN trunk configured on the CPU port. Termination of normal traffic
on switch ports only works when not under a vlan_filtering bridge.
Termination of management (PTP, BPDU) traffic works under all
circumstances because it uses a different tagging mechanism
(incl_srcpt). We are making use of the generic CONFIG_NET_DSA_TAG_8021Q
code and leveraging it from our own CONFIG_NET_DSA_TAG_SJA1105.
There are two types of traffic: regular and link-local.
The link-local traffic received on the CPU port is trapped from the
switch's regular forwarding decisions because it matched one of the two
DMAC filters for management traffic.
On transmission, the switch requires special massaging for these
link-local frames. Due to a weird implementation of the switching IP, by
default it drops link-local frames that originate on the CPU port.
It needs to be told where to forward them to, through an SPI command
("management route") that is valid for only a single frame.
So when we're sending link-local traffic, we are using the
dsa_defer_xmit mechanism.
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>
Resetting the switch at runtime is currently done while changing the
vlan_filtering setting (due to the required TPID change).
But reset is asynchronous with packet egress, and the switch core will
not wait for egress to finish before carrying on with the reset
operation.
As a result, a connected PHY such as the BCM5464 would see an
unterminated Ethernet frame and start to jabber (repeat the last seen
Ethernet symbols - jabber is by definition an oversized Ethernet frame
with bad FCS). This behavior is strange in itself, but it also causes
the MACs of some link partners (such as the FRDM-LS1012A) to completely
lock up.
So as a remedy for this situation, when switch reset is required, simply
inhibit Tx on all ports, and wait for the necessary time for the
eventual one frame left in the egress queue (not even the Tx inhibit
command is instantaneous) to be flushed.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
If STP is active, this setting is applied on bridged ports each time an
Ethernet link is established (topology changes).
Since the setting is global to the switch and a reset is required to
change it, resets are prevented if the new callback does not change the
value that the hardware already is programmed for.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
Documentation/devicetree/bindings/net/ethernet.txt is confusing because
it says what the MAC should not do, but not what it *should* do:
* "rgmii-rxid" (RGMII with internal RX delay provided by the PHY, the MAC
should not add an RX delay in this case)
The gap in semantics is threefold:
1. Is it illegal for the MAC to apply the Rx internal delay by itself,
and simplify the phy_mode (mask off "rgmii-rxid" into "rgmii") before
passing it to of_phy_connect? The documentation would suggest yes.
1. For "rgmii-rxid", while the situation with the Rx clock skew is more
or less clear (needs to be added by the PHY), what should the MAC
driver do about the Tx delays? Is it an implicit wild card for the
MAC to apply delays in the Tx direction if it can? What if those were
already added as serpentine PCB traces, how could that be made more
obvious through DT bindings so that the MAC doesn't attempt to add
them twice and again potentially break the link?
3. If the interface is a fixed-link and therefore the PHY object is
fixed (a purely software entity that obviously cannot add clock
skew), what is the meaning of the above property?
So an interpretation of the RGMII bindings was chosen that hopefully
does not contradict their intention but also makes them more applied.
The SJA1105 driver understands to act upon "rgmii-*id" phy-mode bindings
if the port is in the PHY role (either explicitly, or if it is a
fixed-link). Otherwise it always passes the duty of setting up delays to
the PHY driver.
The error behavior that this patch adds is required on SJA1105E/T where
the MAC really cannot apply internal delays. If the other end of the
fixed-link cannot apply RGMII delays either (this would be specified
through its own DT bindings), then the situation requires PCB delays.
For SJA1105P/Q/R/S, this is however hardware supported and the error is
thus only temporary. I created a stub function pointer for configuring
delays per-port on RXC and TXC, and will implement it when I have access
to a board with this hardware setup.
Meanwhile do not allow the user to select an invalid configuration.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently only the (more difficult) first generation E/T series is
supported. Here the TCAM is only 4-way associative, and to know where
the hardware will search for a FDB entry, we need to perform the same
hash algorithm in order to install the entry in the correct bin.
On P/Q/R/S, the TCAM should be fully associative. However the SPI
command interface is different, and because I don't have access to a
new-generation device at the moment, support for it is TODO.
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>
At this moment the following is supported:
* Link state management through phylib
* Autonomous L2 forwarding managed through iproute2 bridge commands.
IP termination must be done currently through the master netdevice,
since the switch is unmanaged at this point and using
DSA_TAG_PROTO_NONE.
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Georg Waibel <georg.waibel@sensor-technik.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
