The EF10 firmware can optionally insert RX timestamps in the packet
prefix.  These only include the clock minor value.  We must also
enable periodic time sync events on each event queue which provide
the high bits of the clock value.

[bwh: Combined and rebased several changes.
 Added the above description and some sanity checks for inline vs
 separate timestamps.
 Changed efx_rx_skb_attach_timestamp() to read the packet prefix
 from the skb head area.]
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We can potentially pull the entire packet contents into the head area
and then free the page it was in.  In order to read an inline
timestamp safely, we need to copy the prefix into the head area as
well.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

I added efx_ptp_get_mode() to avoid moving the definition for
efx_ptp_data, since the current PTP mode is needed for
siena.c:siena_set_ptp_hwtstamp.

[bwh: Also move the rx_filters mask, and add kernel-doc]
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

The clock minor tick on the SFC9100 family is 2^-27 s, not 1 ns.
There are also various pipeline delays which we need to correct for
when interpreting timestamps.

We query the firmware for the clock format and corrections at run-time.

[bwh: Combined and rebased several changes]
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We'll be sharing clocks between multiple functions with their own MAC
addresses.  The name field is now documented as 'A short "friendly
name" to identify the clock ...' and '... not meant to be a unique
id.'  So use the name 'sfc'.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We need a dedicated channel on Siena to ensure we can match up
the separate RX and timestamp events for each PTP packet.  We won't
do this for EF10 as timestamps are delivered inline.

Pass a channel index of 0 to MC_CMD_PTP_OP_ENABLE when there is no
dedicated channel.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

The MC firmware will return error MC_CMD_ERR_ENOSPC if filter
insertion fails due to lack of resources.  The net driver's filter
implementation for Falcon-architecture returns EBUSY.  They should
behave consistently, so for EF10 change ENOSPC to EBUSY.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

efx_flush_all() is a really misleading name - it has nothing to do
with e.g. flushing DMA queues.  Since it's called immediately after
efx_stop_port() and is highly dependent on what that does, combine
the two functions.

Update comments to explain what this is doing a little better.
Also update an related and erroneous comment in efx_start_port().
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Split each of efx_mcdi_rpc, efx_mcdi_rpc_finish, and efx_mcdi_rpc_async into
a normal and a _quiet version; made the former log MCDI errors with
netif_err (and include the raw MCDI error code), and the latter never log
them at all.  Changed various callers; any where some errors are expected
(but others are not) call the _quiet version and then if necessary log the
MCDI error themselves.  Said logging is done by new efx_mcdi_display_error.

Callers of efx_mcdi_rpc*_quiet functions which may want to log the error
need to ensure that their outbuf is big enough to hold an MCDI error; to
this end, they now use MCDI_DECLARE_BUF_OUT_OR_ERR, which always allocates
at least 8 bytes.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Add units to the "Sensor reports condition X for raw value Y" messages.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We don't directly control RX ingress on Siena or any later
controllers, and so we cannot prevent packets from entering the RX
datapath while the RX queues are not set up.  This results in
the hardware incrementing RX_NODESC_DROP_CNT, but it's not an
error and we should not include it in error stats.

When bringing an interface up or down, pull (or wait for) stats and
count the number of packets that were dropped while the interface was
down.  Subtract this from the reported RX dropped count.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

The addition of RX event merging support means we don't reliably
detect dropped RX events now.  Currently we will only detect them if
the previous event for the RX queue had the CONT bit set.

Only accept RX completion events as merged if the
GET_CAPABILITIES_OUT_RX_BATCHING bit is set in datapath_caps (which it
won't be for the low-latency datapath) and the CONT bit is not set on
the event.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

To run BISTs the MC goes down in to a special mode where it will only
respond to MCDI from the testing PF, and TX, RX and event queues are
torn down. Other PFs get a message as it goes down to tell them it's
going down.

When the other PFs get this message, they check the soft status
register to tell when the MC has rebooted after BIST mode and they can
start recovery.

[bwh: Convert the test result to 1 or -1 as for earlier NICs]
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

The MC firmware is cooperatively multitasking and its scheduler will
send an event when a task yields after running for more than the
expected maximum time.  This can be useful for firmware development
but does not usually indicate a serious error and does not help to
detect a lockup (there is a hardware watchdog that does that).
Change the message and reduce log level accordingly.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

There is an as-yet unexplained bug that sometimes prevents (or delays)
the driver seeing the completion event for a completed MCDI request on
the SFC9120.  The requested configuration change will have happened
but the driver assumes it to have failed, and this can result in
further failures.  We can mitigate this by polling for completion
after unsuccessfully waiting for an event.

Fixes: 8127d661 ('sfc: Add support for Solarflare SFC9100 family')
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

rx_prefix_size is 4-bytes aligned on Falcon/Siena (16 bytes), but it is equal
to 14 on EF10. So, it should be taken into account if arch requires IP header
to be 4-bytes aligned (via NET_IP_ALIGN).

Fixes: 8127d661 ('sfc: Add support for Solarflare SFC9100 family')
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

There is a single MCDI PTP operation for setting the frequency
adjustment and applying a time offset to the hardware clock.  When
applying a time offset we should not change the frequency adjustment.

These two operations can now be requested separately but this requires
a flash firmware update.  Keep using the single operation, but
remember and repeat the previous frequency adjustment.

Fixes: 7c236c43 ('sfc: Add support for IEEE-1588 PTP')
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

This disables PTP when we bring the interface down to avoid getting
unmatched RX timestamp events, and tries to re-enable it when bringing
the interface up.

[bwh: Make efx_ptp_stop() safe on Falcon. Introduce
 efx_ptp_{start,stop}_datapath() functions; we'll expand them later.]

Fixes: 7c236c43 ('sfc: Add support for IEEE-1588 PTP')
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

In case of a flood of PTP packets, the timestamp peripheral and MC
firmware on the SFN[56]322F boards may not be able to provide
timestamp events for all packets.  Don't complain too much about this.

Fixes: 7c236c43 ('sfc: Add support for IEEE-1588 PTP')
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Limit syslog flood if a PTP packet storm occurs.

Fixes: 7c236c43 ('sfc: Add support for IEEE-1588 PTP')
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

efx_ptp_is_ptp_tx() must be robust against skbs from raw sockets that
have invalid IPv4 and UDP headers.

Add checks that:
- the transport header has been found
- there is enough space between network and transport header offset
  for an IPv4 header
- there is enough space after the transport header offset for a
  UDP header

Fixes: 7c236c43 ('sfc: Add support for IEEE-1588 PTP')
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Simplify the code. Avoid race conditions caused by attributes
being created after hwmon device registration. Implicitly
(through hwmon API) add mandatory 'name' sysfs attribute.
Reviewed-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

When using firmware assisted TSO, we use a single DMA mapping for
the linear area of a TSO skb.

We still have to segment the super-packet and insert a descriptor
containing the original headers before each segment of payload, so we
can unmap the linear area only after the last segment is completed.
The unmapping information for the linear area is therefore associated
with the last header descriptor.

We calculate the DMA address to unmap from using the map length and
the invariant that the end of the DMA mapping matches the end of
the data referenced by the last descriptor.  But this invariant is
broken when there is TCP payload in the linear area.

Fix this by adding and using an explicit dma_offset field.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Although we do not yet enable multiple PFs per port, it is possible
that a board will be reconfigured to enable them while the driver has
not yet been updated to fully support this.

The most obvious problem is that multiple functions may try to set
conflicting link settings.  But we will also run into trouble if the
firmware doesn't consider us fully trusted.  So, abort probing unless
both the LinkCtrl and Trusted flags are set for this function.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Recognise the new Packet Memory and RX Data Path counters.

The following counters are added:
rx_pm_{trunc,discard}_bb_overflow - burst buffer overflowed.  This should not
 occur if BB correctly configured.
rx_pm_{trunc,discard}_vfifo_full - not enough space in packet memory.  May
 indicate RX performance problems.
rx_pm_{trunc,discard}_qbb - dropped by 802.1Qbb early discard mechanism.
 Since Qbb is not supported at present, this should not occur.
rx_pm_discard_mapping - 802.1p priority configured to be dropped.  This should
 not occur in normal operation.
rx_dp_q_disabled_packets - packet was to be delivered to a queue but queue is
 disabled.  May indicate misconfiguration by the driver.
rx_dp_di_dropped_packets - parser-dispatcher indicated that a packet should be
 dropped.
rx_dp_streaming_packets - packet was sent to the RXDP streaming bus, ie. a
 filter directed the packet to the MCPU.
rx_dp_emerg_{fetch,wait} - RX datapath had to wait for descriptors to be
 loaded.  Indicates performance problems but not drops.

These are only provided if the MC firmware has the
PM_AND_RXDP_COUNTERS capability.  Otherwise, mask them out.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>