sfc: Miscellaneous comment removals

Remove comments that only apply to Falcon and Siena.

Signed-off-by: Martin Habets <habetsm.xilinx@gmail.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: Remove struct efx_special_buffer

The attributes index and entries are no longer needed, so use
struct efx_buffer instead.
next_buffer_table was also Siena specific.
Removed some checkpatch warnings.

Signed-off-by: Martin Habets <habetsm.xilinx@gmail.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: Remove EFX_REV_SIENA_A0

The workarounds for bug 8568 and 17213 are no longer needed.

Signed-off-by: Martin Habets <habetsm.xilinx@gmail.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: The size of the RX recycle ring should be more flexible

Ideally the size would depend on the link speed, but the recycle
ring is created when the interface is brought up before the driver
knows the link speed. So size it for the maximum speed of a given NIC.
PowerPC is only supported on SFN7xxx and SFN8xxx NICs.

With this patch on a 40G NIC the number of calls to alloc_pages and
friends went down from about 18% to under 2%.
On a 10G NIC the number of calls to alloc_pages and friends went down
from about 15% to 0 (perf did not capture any calls during the 60
second test).
On a 100G NIC the number of calls to alloc_pages and friends went down
from about 23% to 4%.

Reported-by: Íñigo Huguet <ihuguet@redhat.com>
Signed-off-by: Martin Habets <habetsm.xilinx@gmail.com>
Link: https://lore.kernel.org/r/20220131111054.cp4f6foyinaarwbn@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: sfc: Replace in_interrupt() usage

efx_ef10_try_update_nic_stats_vf() used in_interrupt() to figure out
whether it is safe to sleep (for MCDI) or not.

The only caller from which it was not is efx_net_stats(), which can be
invoked under dev_base_lock from net-sysfs::netstat_show().

So add a new update_stats_atomic() method to struct efx_nic_type, and call
it from efx_net_stats(), removing the need for
efx_ef10_try_update_nic_stats_vf() to behave differently for this case
(which it wasn't doing correctly anyway).

For all nic_types other than EF10 VF, this method is NULL so the the
regular update_stats() methods are invoked , which are happy with being
called from atomic contexts.

Fixes: f00bf2305cab ("sfc: don't update stats on VF when called in atomic context")
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Martin Habets <mhabets@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: remove efx_tx_queue_partner

All users of this function are now gone.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

sfc: rewrite efx_tx_may_pio

Use efx_for_each_channel_tx_queue() rather than efx_tx_queue_partner().
Make some related simplifications of efx_nic_tx_is_empty() to remove
entry points that aren't used.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

sfc: skeleton EF100 PF driver

No TX or RX path, no MCDI, not even an ifup/down handler.
Besides stubs, the bulk of the patch deals with reading the Xilinx
extended PCIe capability, which tells us where to find our BAR.

Though in the same module, EF100 has its own struct pci_driver,
which is named sfc_ef100.

A small number of additional nic_type methods are added; those in the
TX (tx_enqueue) and RX (rx_packet) paths are called through indirect
call wrappers to minimise the performance impact.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc_ef100: add EF100 to NIC-revision enumeration

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: assign TXQs without gaps

Since we only allocate VIs for the number of TXQs we actually need, we
cannot naively use "channel * TXQ_TYPES + txq" for the TXQ number, as
this has gaps (when efx->tx_queues_per_channel < EFX_TXQ_TYPES) and
thus overruns the driver's VI allocations, causing the firmware to
reject the MC_CMD_INIT_TXQ based on INSTANCE.
Thus, we distinguish INSTANCE (stored in tx_queue->queue) from LABEL
(tx_queue->label); the former is allocated starting from 0 in
efx_set_channels(), while the latter is simply the txq type (index in
channel->tx_queue array).
To simplify things, rather than changing tx_queues_per_channel after
setting up TXQs, make Siena always probe its HIGHPRI queues at start
of day, rather than deferring it until tc mqprio enables them.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: don't call tx_remove if there isn't one

EF100 won't have an efx->type->tx_remove method, because there's
nothing for it to do. So make the call conditional.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: move definition of EFX_MC_STATS_GENERATION_INVALID

Saves a whole #include from nic.c.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: remove duplicate declaration of efx_enqueue_skb_tso()

Define it in nic_common.h, even though the ef100 driver will have a
different implementation backing it (actually a WARN_ON_ONCE as it
should never get called by ef100. But it needs to still exist because
common TX path code references it).

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfc: split up nic.h

The new nic_common.h contains the inlines for NIC-type function dispatch,
declarations for NIC-generic functions in nic.c, and other similar NIC-
generic functionality. Retained in nic.h are NIC-specific declarations
such as the siena and ef10 nic_data structs and various farch functions.

The EF100 driver will thus include nic_common.h but not nic.h.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>