In Falcon we can configure the fill levels of the RX data FIFO which
trigger the generation of pause frames (if enabled), and we have
module parameters for this.

Siena does not allow the levels to be configured (or, if it does, this
is done by the MC firmware and is not configurable by drivers).

So far as I can tell, the module parameters are not used by our
internal scripts and have not been documented (with the exception of
the short parameter descriptions).  Therefore, remove them and always
initialise Falcon with the default values.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

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

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

This field does not exist in all MMDs we want to check, and all
callers allow it to be set (fault_fatal = 0).

Remove the loopback condition, as STAT2.DEVPRST should be valid
regardless of any fault.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

We currently make no use of siena_nic_data::fw_{version,build} except
to format the firmware version for ethtool_get_drvinfo().  Since we
only read the version at start of day, this information is incorrect
after an MC firmware update.  Remove the cached version information
and read it via MCDI whenever it is requested.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Instead calculate the KVA of receive data. It's not like it's a hard sum.

[bwh: Fixed to work with GRO.]
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

[bwh: Forward-ported to net-next-2.6.]
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Use the existing filter management functions to insert TCP/IPv4 and
UDP/IPv4 4-tuple filters for Receive Flow Steering.

For each channel, track how many RFS filters are being added during
processing of received packets and scan the corresponding number of
table entries for filters that may be reclaimed.  Do this in batches
to reduce lock overhead.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

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

Implement the ndo_setup_tc() operation with 2 traffic classes.

Current Solarstorm controllers do not implement TX queue priority, but
they do allow queues to be 'paced' with an enforced delay between
packets.  Paced and unpaced queues are scheduled in round-robin within
two separate hardware bins (paced queues with a large delay may be
placed into a third bin temporarily, but we won't use that).  If there
are queues in both bins, the TX scheduler will alternate between them.

If we make high-priority queues unpaced and best-effort queues paced,
and high-priority queues are mostly empty, a single high-priority queue
can then instantly take 50% of the packet rate regardless of how many
of the best-effort queues have descriptors outstanding.

We do not actually want an enforced delay between packets on best-
effort queues, so we set the pace value to a reserved value that
actually results in a delay of 0.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

efx_channel_get_{rx,tx}_queue() currently return NULL if the channel
isn't used for traffic in that direction.  In most cases this is a
bug, but some callers rely on it as an existence test.

Add existence test functions efx_channel_has_{rx_queue,tx_queues}()
and use them as appropriate.

Change efx_channel_get_{rx,tx}_queue() to assert that the requested
queue exists.

Remove now-redundant initialisation from efx_set_channels().
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

efx_hard_start_xmit() needs to implement a mapping which is the
inverse of tx_queue::core_txq.  Move the initialisation of
tx_queue::core_txq next to efx_hard_start_xmit() to make the
connection more obvious.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Quoting Ben Hutchings: we presumably won't be defining features that
can only be enabled on 64-bit architectures.

Occurences found by `grep -r` on net/, drivers/net, include/

[ Move features and vlan_features next to each other in
  struct netdev, as per Eric Dumazet's suggestion -DaveM ]
Signed-off-by: NMichał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit a4900ac9 ("sfc: Create multiple TX queues") accidentally
disabled the rss_cpus module parameter.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

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

pci_restore_state only ever returns 0, thus there is no benefit in
having it return any value.  Also, a large majority of the callers do
not check the return code of pci_restore_state.  Make the
pci_restore_state a void return and avoid the overhead.
Acked-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NJon Mason <jon.mason@exar.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Various drivers are using implementations of ethtool_ops::get_link
that are equivalent to the default ethtool_op_get_link().  Change
them to use that instead.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This driver now uses Generic Receive Offload, not the older LRO.
Change references to LRO in names and comments.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Long before this driver went into mainline, it had support for
multiple TX queues per port, with lockless TX enabled.  Since Linux
did not know anything of this, filling up any hardware TX queue would
stop the core TX queue and multiple hardware TX queues could fill up
before the scheduler reacted.  Thus it was necessary to keep a count
of how many TX queues were stopped and to wake the core TX queue only
when all had free space again.

The driver also previously (ab)used the per-hardware-queue stopped
flag as a counter to deal with various things that can inhibit TX, but
it no longer does that.

Remove the per-channel tx_stop_count, tx_stop_lock and
per-hardware-queue stopped count and just use the networking core
queue state directly.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

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

Call netif_napi_{add,del}() on the NAPI contexts in the new and
old channels, respectively.

Since efx_init_napi() cannot fail, make its return type void.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

If we are using a legacy interrupt, our IRQ may be shared and our
interrupt handler may be called even though interrupts are disabled on
the NIC. When we change ring sizes, we reallocate the event queue and
the interrupt handler may use an invalid pointer when called for
another device's interrupt.

Maintain a legacy_irq_enabled flag and test that at the top of the
interrupt handler.  Note that this problem results from the need to
work around broken INT_ISR0 reads, and does not affect the legacy
interrupt handler for Falcon A1.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Move search_depth arrays into per-table state.

Define initialisation function efx_filter_init_rx() which sets
everything apart from the match fields.

Define efx_filter_set_{ipv4_local,ipv4_full,eth_local}() to set the
match fields.  This allows some simplification of callers and later
support for additional protocols and more flexible matching using
multiple calls to these functions.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

The separation between filter tables is largely an internal detail
and it may be removed in future hardware.  To prepare for that:

- Merge table ID with filter index to make an opaque filter ID
- Wrap efx_filter_table_clear() with a function that clears filters
  from both RX tables, which is all that the current caller requires
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Add message at start of self-test and increase log level of message at
end of self-test, so that any other messages produced during the
test are clearly associated with it.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

Whenever we add DMA descriptors to a TX ring and update the ring
pointer, the TX DMA engine must first read the new DMA descriptors and
then start reading packet data.  However, all released Solarflare 10G
controllers have a 'TX push' feature that allows us to reduce latency
by writing the first new DMA descriptor along with the pointer update.
This is only useful when the queue is empty.  The hardware should
ignore the pushed descriptor if the queue is not empty, but this check
is buggy, so we must do it in software.

In order to tell whether a TX queue is empty, we need to compare the
previous transmission count (write_count) and completion count
(read_count).  However, if we do that every time we update the ring
pointer then read_count may ping-pong between the caches of two CPUs
running the transmission and completion paths for the queue.
Therefore, we split the check for an empty queue between the
completion path and the transmission path:

- Add an empty_read_count field representing a point at which the
  completion path saw the TX queue as empty.
- Add an old_write_count field for use on the completion path.
- On the completion path, whenever read_count reaches or passes
  old_write_count the TX queue may be empty.  We then read
  write_count, set empty_read_count if read_count == write_count,
  and update old_write_count.
- On the transmission path, we read empty_read_count.  If it's set, we
  compare it with the value of write_count before the current set of
  descriptors was added.  If they match, the queue really is empty and
  we can use TX push.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

It is not necessary to serialise writes to the paged 128-bit
registers.  However, if we don't then we must always write the last
dword separately, not as part of a qword write.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

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

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

Document exactly which registers and functions have special behaviour,
and why races on writes to descriptor pointers are safe.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

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

Place the regularly updated fields (locks, MAC stats, etc.) on a
separate cache-line from fields which are mostly constant.  This
should reduce cache misses for access to the latter on the data path.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>

For some reason we failed to make this change when perm_addr was
introduced.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We only have direct access to MDIO on Falcon, so move this out of
struct efx_nic.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We only have direct access to SPI on Falcon, so move all this state
out of struct efx_nic.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>