During NIC initialization shared HW is reset and this disables the
scheduler. Some HW platforms do not activate the scheduler after it.
Consequently all HCMD sent by the driver stay at the queues which cause
to queue stuck.
Set the scheduler to work on auto active mode so it would be activated upon
change over one of the queues' write pointer.
Signed-off-by: NHaim Dreyfuss <haim.dreyfuss@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

This check for family type is redundant as the if clause above
checks a family-dependent Boolean (which is not set for family 8000 anyway).
Signed-off-by: NAvri Altman <avri.altman@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

The cmd_in_flight tracking was introduced to workaround faulty
power management hardware, by having the driver keep the NIC
awake as long as there are commands in flight. However, some of
the code handling this workaround was unconditionally executed,
which resulted with an inconsistent state where the driver assumed
that the NIC was awake although it wasn't.

Fix this by renaming 'cmd_in_flight' to 'cmd_hold_nic_awake' and
handling the NIC requested awake state only for hardwares for
which the workaround is needed.
Signed-off-by: NIlan Peer <ilan.peer@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

This allows the op_mode to let the transport know that a
queue is currently frozen and that its timer should be
stopped.
When the queue is unfrozen, its timer should be set to
expire after the remainder of the timeout has elapsed.
This can be used when stations go to sleep. When a station
goes to sleep, the op_mode can freeze the timer so that the
queue will never be considered as stuck. When the station
wakes up, the queue will be unfrozen.
This is meant to avoid false positives that would happen if
a buggy station goes to sleep for a very long time. In case
we have a dedicated queue for this station (BA agreement)
and it goes to sleep for a very long time, the queue would
rightfully be stopped during all that time. In this case,
the stuck queue timer could fire and that would be a false
positive.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

We don't need to acquire MAC access for each access, it
makes much more sense to keep the MAC access. This speeds
up the Tx DMA stop flow significantly.
Moreover, if one channel can't be stopped, stop the others
but don't poll for them to avoid being stuck there for a
long time.

This solves a situation in which we were stuck in that flow
for way too long with a spinlock held which led to a kernel
panic.
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Different queue can have different behavior. While it can be
unacceptable for a certain queue to be stuck for 2 seconds
(e.g. the command queue), it can happen that another queue
will stay stuck for even longer (a queue servicing a power
saving client in GO).
The op_mode can even make the timeout be a function of the
listen interval.
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

This watchdog allows to monitor the transmit queues. When a
queue doesn't progress for a too long time, a timer fires
and then, debug data can be collected.
This watchdog has never been enabled on dvm controlled
devices, so don't enable it there.
In order to have it running on mvm controlled devices, we
need to fix a small issue in the transport layer: mvm
controlled devices use the shadow registers optimization.
In this case, the watchdog wasn't running at all, even if
enabled by the module parameter. Fix that on the way.
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

The base address of the scheduler in the device's memory
(SRAM) comes from two different sources. The periphery
register and the alive notification from the firmware.
We have a check in iwl_pcie_tx_start that ensures that
they are the same.
When we resume from WoWLAN, the firmware may have crashed
for whatever reason. In that case, the whole device may be
reset which means that the periphery register will hold a
meaningless value. When we come to compare
trans_pcie->scd_base_addr (which really holds the value we
had when we loaded the WoWLAN firmware upon suspend) and
the current value of the register, we don't see a match
unsurprisingly.
Trick the check to avoid a loud yet harmless WARN.
Note that when the WoWLAN has crashed, we will see that
in iwl_trans_pcie_d3_resume which will let the op_mode
know. Once the op_mode is informed that the WowLAN firmware
has crashed, it can't do much besides resetting the whole
device.

CC: <stable@vger.kernel.org>
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Some devices have 31 TFD queues. Don't enable it yet since
there are still issues with it, but at least prepare the
code for it. There was a bug in the read pointer assignment,
fix that. Also, move the inline functions to iwl-scd.h which
is the right place.
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Printing all the scratch data of the TFDs of that queue is
useless and stuffed the kernel log with data. Remove that.
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

A new host command can be used to configure the scheduler
instead of accessing the scheduler's registers from the
driver. This is easier and less error prone since accessing
the hardware at certain moments can lead to races with the
firmware.
Prefer to use the host command whenever it is available.
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Implement the ref/unref trans ops and track both tx and
host command queues (and hold references while they
are not empty).
Signed-off-by: NEliad Peller <eliadx.peller@intel.com>
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

A following patche will use trans_pcie->cmd_in_flight
for reference accounting as well. get ready for it.
Signed-off-by: NEliad Peller <eliadx.peller@intel.com>
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

In some rare cases, the firmware can put the device to
sleep after the driver requested the access. This is
because the access request can take a short time to be
propagated to the firmware.

If that happens, the driver may think that it has access
since the firmware hasn't put the device to sleep yet, but
right after the driver's check, the firmware might put the
device to sleep.

Warn when this happens by allowing the firmware to finish
the "put the device sleep" flow so that the driver will
not get access to the device. This will make the issue
visible.

This still doesn't fix the race, but at least it makes
it more visible.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

When freeing the structures used for command data, clear their
memory as they may have contained key material at some point.
Also clear the duplicated buffer when freeing it to be safe;
currently key material is never put there but that may change.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

This configuration is not needed for dvm, and it actually
broke it.
Reported-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Our legal structure changed at some point (see wikipedia), but
we forgot to immediately switch over to the new copyright
notice.

For files that we have modified in the time since the change,
add the proper copyright notice now.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Currently the firmware is handling this, but that is wrong as it then
needs to assume a certain command queue, therefore this should be in
the driver; add it here so it can be removed from the firmware in the
future.
Signed-off-by: NAvri Altman <avri.altman@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Currently a valid sta_id is assumed to mean that the queue is
meant to also be aggregated, but that assumption will not be
true in the future, so don't make it in the lower level but
only in the inline wrapper.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

In a later patch, the hardware configuration will be moved to
firmware. Prepare for this by allowing hardware configuration
in the transport to be skipped by not passing a configuration
on enable and passing configure_scd=false on disable.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Instead of having all arguments passed to the function,
add a struct to hold them and only pass some directly.

This will make future work in this area cleaner.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Configuring the hw scheduler during queue enablement is done by
writing the appropriate values to the scheduler peripherals, and
it is essentially the same for all buses.

Whenever writing is done via the standard iwl_write_prph, we can
avoid duplicating the code for each bus. Those operations are
queue deactivation, RA/TID mapping, chain-building settings,
enabling/disabling aggregations and activating/deactivating the
TX FIFOs.

Consolidate this code using static inlines in a new header file.
Signed-off-by: NAvri Altman <avri.altman@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

I've never seen this happen, but it's useful to rule it out.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

In the 8000 HW family the register for forcing an NMI has
changed, so this allows to still be able to force an NMI
while taking into account the HW in order to write to the
correct register.
Signed-off-by: NLiad Kaufman <liad.kaufman@intel.com>
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

This fixes:

=================================
[ INFO: inconsistent lock state ]
3.14.3+ #5 Tainted: G           O
---------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
swapper/3/0 [HC0[0]:SC1[3]:HE1:SE0] takes:
 (&(&txq->lock)->rlock){+.?...}, at: [<ffffffffa059803c>] iwl_pcie_enqueue_hcmd+0x12c/0x1000 [iwlwifi]
{SOFTIRQ-ON-W} state was registered at:
  [<ffffffff810d9071>] __lock_acquire+0x5f1/0x13b0
  [<ffffffff810d9ee0>] lock_acquire+0xb0/0x1f0
  [<ffffffff817ef80e>] _raw_spin_lock+0x3e/0x80
  [<ffffffffa0598f7a>] iwl_pcie_txq_check_wrptrs+0x6a/0xb0 [iwlwifi]
  [<ffffffffa0594b5a>] iwl_pcie_irq_handler+0xdba/0x2670 [iwlwifi]
  [<ffffffff810ef1e0>] irq_thread_fn+0x20/0x50
  [<ffffffff810ef77f>] irq_thread+0x11f/0x150
  [<ffffffff810a04f0>] kthread+0xf0/0x110
  [<ffffffff817fa4bc>] ret_from_fork+0x7c/0xb0
irq event stamp: 1142192
hardirqs last  enabled at (1142192): [<ffffffff817efb6c>] _raw_spin_unlock_irq+0x2c/0x40
hardirqs last disabled at (1142191): [<ffffffff817ef9ef>] _raw_spin_lock_irq+0x1f/0x80
softirqs last  enabled at (1142188): [<ffffffff81079082>] _local_bh_enable+0x22/0x50
softirqs last disabled at (1142189): [<ffffffff8107ad35>] irq_exit+0xe5/0xf0

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&txq->lock)->rlock);
  <Interrupt>
    lock(&(&txq->lock)->rlock);

Fixes: ea68f460 ("iwlwifi: pcie: clarify TX queue need_update handling")
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

When a firmware error occurs, capture the last 32 commands
(which are still in memory) in the error dump debugfs file.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

This variable always tracks a constant value (256) so there's
no need to have it. Removing it simplifies code generation,
reducing the .text size (by about 240 bytes on x86-64.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

The 'reset' argument is clearly a boolean, so use bool instead
of u8 with 0/1 values.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

7000 device series have a fix for this hardware feature.
Stop disabling it, and get an improvement in Tx throughput.
This feature allows the scheduler to fetch more frames on
the fly while an A-MPDU is being built - which means that
we can get larger A-MPDU. This, of course, give an
improvement in the Tx throughput.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Similar to the recent RX queue patch, this changes the need_update
handling for the TX queues to be clearer and only done when needed.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Instead of using u8 to hold logic values, use bool.

Also fix a comment, the return value is no longer relevant.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

A hardware bug had been discovered on 7260 / 3160 and 7265
and the workaround for this bug is to force the NIC to stay
awake as long as we have host commands in flight. This
workaround has been introduced for all NICs in a previous
patch:

b9439491 ("iwlwifi: pcie: keep the NIC awake when commands are in flight")

In newer NICs, this bug is solved, so we can let the NIC go
to sleep even when we send commands. The hardware will wake
up when we increment the scheduler write pointer.
Make the workaround conditional to only use it on affected
hardware.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

In case the firmware didn't assert but we want to restart
it, e.g. we didn't get the reply for a host command, or the
Tx queues are stuck, we should stop the firmware by
provoking an interrupt. This allows to better debug the
firmware in these bad scenarios.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

The various code blocks in iwl_pcie_[rt]xq_inc_wr_ptr
finally do the same things, so just merge them
all and make the functions cleaner.
Signed-off-by: NEliad Peller <eliadx.peller@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

APMG HW block was removed in this NIC, hence, no need to
configure it.
Signed-off-by: NEran Harary <eran.harary@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

None of the devices supported by iwldvm have support for
shadow registers. This means that we wake the NIC
when we increment the write pointer on Tx ring.
This happened even before my bad commit mentionned below.
Since my commit below, we wake up the NIC when we put a
host command on the ring regardless of shadow register
support. This means that in iwldvm (when the NIC doesn't
support shadow register), we wake up the NIC twice:

pcie_enqueue_hcmd:
	wake up the NIC
	iwl_pcie_txq_inc_wr_ptr:
		wake up the NIC - no shadow reg support

Since waking up the NIC means that we need to acquire a
spinlock, this obviously leads to a recursive spinlock
and hence a freeze.

Fixes: b9439491 ("iwlwifi: pcie: keep the NIC awake when commands are in flight")
Reported-by: NJanusz Dziedzic <janusz.dziedzic@gmail.com>
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Happy new year!
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Calling stop_device when start_fw wasn't called would issue:
Stopping tx queues that aren't allocated...

Also allow the op_mode to call stop_device and then to
disable the Tx queues - in that case just silently ignore
the disabling on the Tx queues, since the PRPH registers
aren't reachable any more.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Under very specific circumstances, the firmware might
ignore a host command. This was debugged and we ended up
seeing that the power management hardware was faulty.
In order to workaround this issue, we keep the NIC awake
as long as we have host commands in flight. This will avoid
to put the hardware into buggy condition.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>

Since we don't take this lock in the primary interrupt
handler, there is no pointin disabling the interrupt
in the critical section protected by trans_pcie->irq_lock.
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>