When interface stopped while running intensive Rx traffic, the following oops
observed:

[89846.734683] Call trace:
[89846.737117] [<ffffffc00083aa64>] dev_gro_receive+0xac/0x358
[89846.742674] [<ffffffc00083ae94>] napi_gro_receive+0x24/0xa4
[89846.748251] [<ffffffbffc1c2f88>] $x+0xec/0x1f8 [wil6210]         wil_netif_rx_any
[89846.753547] [<ffffffbffc1c4830>] $x+0x34/0x54 [wil6210]          wil_release_reorder_frame
[89846.758755] [<ffffffbffc1c48ac>] wil_release_reorder_frames+0x5c/0x78 [wil6210]
[89846.766044] [<ffffffbffc1c4bf8>] wil_tid_ampdu_rx_free+0x20/0x48 [wil6210]
[89846.772901] [<ffffffbffc1bedc8>] $x+0x190/0x1e8 [wil6210]
[89846.778285] [<ffffffbffc1c0ed4>] wmi_event_worker+0x230/0x2f8 [wil6210]
[89846.784865] [<ffffffc0000b0bc8>] process_one_work+0x278/0x3fc
[89846.790591] [<ffffffc0000b1218>] worker_thread+0x200/0x330
[89846.796060] [<ffffffc0000b6664>] kthread+0xac/0xb8
[89846.800836] Code: b940c661 f9406a62 8b010041 f9400026 (f8636882)
[89846.807008] ---[ end trace d6fdc17cd27d18f6 ]---

Reason is the following: when removing Rx vring
(wil_netdev_ops.ndo_stop -> wil_stop -> wil_down -> __wil_down -> wil_rx_fini),
Rx interrupt occurs. It trigger Rx NAPI, calling wil_rx_handle() that reaps
(already cleaned) buffer, causing skb referring to garbage memory being set into reorder buffer.
Then, network stack trying to access this buffer and fails.

Prevent Rx NAPI from being scheduled if device going to stop. Bit wil_status_napi_en reflects
NAPI enablement state, check it when triggering Rx NAPI.

Testing shows that check for wil_status_napi_en sometimes gets negative, and new error message
get printed - in this case kernel oops would be observed. Original oops is no more reproducible.

This change requires also changes in the AP flows.
Properly enable/disable NAPI for the AP. Make sure Rx VRING is disabled
when resetting target.

For this, promote __wil_up() and __wil_down() to the module scope, and use it
in the relevant flows.
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

To better reflect real action performed, rename:
s/wil6210_disable_irq/wil_mask_irq/
s/wil6210_enable_irq/wil_unmask_irq/
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

After setting interrupt handler, driver enabled interrupts.
This caused stale (old) HW interrupts to fire before driver is
fully initialized.
The fix is to enable interrupts only when driver is fully initialized
and after FW/HW reset (to prevent any stale interrupts)
Signed-off-by: NDedy Lansky <qca_dlansky@qca.qualcomm.com>
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

added misc printouts in some init/uninit functions for better traceability
Signed-off-by: NDedy Lansky <qca_dlansky@qca.qualcomm.com>
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Firmware download implemented but is still experimental feature;
flag controlling it added, no_fw_load. It is true by default,
use no_fw_load=N to activate feature.

Reset flows also got some adjustment for the fw download to work
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fix Copyright headers in all files changed in 2014, to mention 2014
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Track number of interrupts and Tx/Rx packets;
expose through debugfs 'info'. Reset upon read.
Used to analyse effectivness of interrupt coalescing and NAPI.
Read twice with some interval like
cat info > /dev/null; sleep 1; cat info
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Print to dmesg when FW error notification is about to be sent
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Reshuffle prints to consolidate firmware/hardware information
report upon card init

Convert print for unhandled MISC ISR bits to "debug" - it is
normal situation and not an "error"
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

upon fw error interrupt - in STA mode, disconnect/cancel scan and
then reset FW/HW
added module param - no_fw_recovery which is false by default
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

wil_reset() removes vring's
At the same time NAPI may be active performing Rx/Tx completion.
If this happens, Rx/Tx polling functions going to access already removed vrings

Make sure NAPI is idle and won't be started prior to vring removal.
For this, track NAPI enabled state
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Hardware bug triggered by the MSI init while INTx asserted for some reason.
De-assert INTx prior to MSI set-up
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Use hardware capabilities to limit IRQ generation to about 15 per msec
It corresponds to about 7 packets/IRQ when running iperf with default
parameters at 1.3Gbps

Do not enable this feature in the sniffer (monitor)  mode, because
interrupt moderation cause timestamp accuracy deterioration.
For the sniffer flow, it is important to get precise timestamp.
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Introduce NAPI for Rx and Tx completion.

This fixes packet reordering that happens when Rx handled right in
the IRQ: netif_rx puts packet in 'percpu' queue, then network stack
fetches packets from 'percpu' queues for processing, with different
pattern of queue switching. As result, network stack see packets
in different order. This causes hard to understand TCP throughput
degradation in about 30min

Complete polling if only one packet was processed - this eliminates
empty polls that would be otherwise done at the end of each burst
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Trace the following:
- WMI cmd/event
- log events
- interrupts
- Tx/Rx
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

New firmware allows for shorter SW reset procedure.
After SW reset, FW raises "fw done" IRQ, at this
moment mailbox control structures are initialized, driver caches it.

New status bit wil_status_reset_done introduced to track completion
of the reset. It is set by "fw ready" irq, and required for WMI rx flow
to access control structures.

WMI Tx flow protected by other status bit, wil_status_fwready. It can't
be set before wil_status_reset_done is set by design.
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

user space get notified through kobject_uevent_env(), that might sleep and thus
should run in thread context.

Move user space notification to the thread handler, while mark FW is non-functional
right in the hard IRQ.
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Make printings from IRQ appears in dmesg in chronological order
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In the firmware, added is ability to report internal errors using IRQ.

Catch this IRQ and notify user space via netlink

User space get notified like (udevadm monitor --kernel --property):

KERNEL[12660.320520] change   /devices/pci0000:00/0000:00:1c.1/0000:02:00.0/0000:03:01.0/0000:05:00.0/net/wlan12 (net)
ACTION=change
DEVPATH=/devices/pci0000:00/0000:00:1c.1/0000:02:00.0/0000:03:01.0/0000:05:00.0/net/wlan12
DEVTYPE=wlan
EVENT=FW_ERROR
IFINDEX=6
INTERFACE=wlan12
SEQNUM=2489
SOURCE=wil6210
SUBSYSTEM=net
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This adds support for the 60 GHz 802.11ad Wilocity card
through a new driver, wil6210. Wilocity implemented the
firmware, QCA maintains the device driver.

Currently supported:

- STA: with security
- AP: limited to 1 connected STA, security disabled
- Monitor: due to a hardware/firmware limitation
  either control or non-control frames are monitored

Using a STA and AP with this drive, one can assemble
a fully functional BSS. Throughput of 1.2Gbps is achieved
with iperf.

The wil6210 cards have on-board flash memory for the
firmware, the cards comes pre-flashed and no firmware
download is required.

For more details see:

http://wireless.kernel.org/en/users/Drivers/wil6210Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NLuis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>