Recently in commit 8a964f44
("iwlwifi: always copy first 16 bytes of commands") we fixed
the problem that the hardware writes back to the command and
that could overwrite parts of the data that was still needed
and would thus be corrupted.

Investigating this problem more closely we found that this
write-back isn't really ordered very well with respect to
other DMA traffic. Therefore, it sometimes happened that the
write-back occurred after unmapping the command again which
is clearly an issue and could corrupt the next allocation
that goes to that spot, or (better) cause IOMMU faults.

To fix this, allocate coherent memory for the first 16 bytes
of each command, containing the write-back part, and use it
for all queues. All the dynamic DMA mappings only need to be
TO_DEVICE then. This ensures that even when the write-back
happens "too late" it can't hit memory that has been freed
or a mapping that doesn't exist any more.

Since now the actual command is no longer modified, we can
also remove CMD_WANT_HCMD and get rid of the DMA sync that
was necessary to update the scratch pointer.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The IWL_MAX_CMD_TFDS name for this constant is wrong, the
constant really indicates how many TBs we can use in the
driver for a single command TFD, rename the constant and
also add a comment explaining it.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

With new transports coming up, move to threaded
interrupt handling now. This has the advantage
that we can use the same locking scheme with all
different transports we may need to implement.

Note that the TX path obviously still runs in a
tasklet, so some spin_lock() calls need to change
to spin_lock_bh() calls to properly lock out the
TX path.

In my test on a Calpella platform this has no
impact on throughput or latency.

Also add lockdep annotations to avoid lockups due
to catch sending synchronous commands or using
locks that connect with them from the irq thread.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Move the reg_lock that protects HW register access
into the transport implementation. Locking is no
longer exposed, but handled internally in grab and
release NIC access. This simplifies the users.
Signed-off-by: NLilach Edelstein <lilach.edelstein@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Express iwl_set_bit() and iwl_clear_bit() through iwl_set_bits_mask()
and add the latter to the transport's API in order to allow different
implementation for different transport types in the future.
Signed-off-by: NLilach Edelstein <lilach.edelstein@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Just format the enum better.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When the pages are to be used by front-end, it may need
to know the page order, provide it.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Update Copyright notices to 2013.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

On resuming, the opmode may have to be able to talk
to the WoWLAN/D3 firmware in order to query it about
its status and wakeup reasons. To do that, the opmode
has to call the new d3_resume() transport API which
will set up the device for command communcation.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Sending a NULL pointer to iwl_trans_write_mem allows now
to zero SRAM.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This allows to let sparse check that the NIC access is
always released.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Different transports implement the access to the SRAM in
different ways. Virtualize it.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since different transports have different ways to wake the
up the NIC, we need to virtualize it.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

In some cases, the fw should run even if the NIC is in
RFKILL. Make the API more flexible to allow that.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This is needed for newer NICs.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

New transports may handle it internally for better performance.
Also move the tracing inside PRPH access which will make the
output more readable:

iwlwifi_dev_ioread_prph32: Read 0x0 from SCD_AGGR_SEL (32-bit)

instead of the corresponding accesses to HBUS_TARG_PRPH_*.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since the op_mode is leaving, the transport should set
its pointer to it to NULL to not point to freed memory.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The ALIVE response of new fw inclues the base address of
the SCD in SRAM. Until we read it from a prph register,
which was set by the fw. Since the fw might well stop
updating the prph register, add a WARN when there is an
inconsitency between the ALIVE response and the register
to catch any change in the behavior.
Reviewed-by: NGregory Greenman <gregory.greenman@intel.com>
Reviewed-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

No HCMD can be sent while RFKILL is asserted. If a SYNC
command is running while RFKILL is asserted the fw will
silently discard it. This means that the driver needs to
wake the process that sleeps on the CMD_SYNC.

Since the RFKILL interrupt is handled in the transport layer
and the code that sleeps in CMD_SYNC is also in the transport
layer, all this logic can be handled there.
This simplifies the work of the op_mode.

So the transport layer will now return -ERFKILL when a CMD
is sent and RFKILL is asserted. This will be the case even
when the CMD is SYNC. The transport layer will return
-ERFKILL straight away.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Clarify the documentation to indicate that these
flags can only be used at the end, i.e. after them
a copy TFD (no flags set) is invalid.
Reported-by: NInbal Hacohen <inbal.hacohen@intel.com>
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

In addition to the NOCOPY flag, add a DUP flag that
tells the transport to kmemdup() the buffer and free
it after the command completes.

Currently this is only supported for a single buffer
in a given command, but that could be extended if it
should be needed.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When tracing in iwlwifi, we get all data. Most of
the time, we don't need it, and it just takes up
a lot of extra space in the trace.

Make this optional by recording the data into two
separate trace events if it is needed. Without it,
record only the content of non-data and EAPOL TX
frames.

As a result, tracing without the data tracepoints
will record meta information including the 802.11
headers for all frames but will not record the
contents of data frames to reduce trace overhead.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Until now, the response handler of a Host Command got the
exact same pointer that was also given to the DMA engine.
We almost never need to the Host Command that was sent while
handling its response, but when we do need it, we see that
the command has been modified.

This mystery has been elucidated. The FH (our DMA engine)
writes its meta data on the buffer in the DRAM. Of course it
copies the buffer to the NIC first. This was known to happen
for Tx command, but as a matter of fact, it happens to all
TFD brought by the FH which doesn't care much about what it
brings from DRAM to internal SRAM.

So copy the Host Command to yet another buffer so that we
can properly pass the buffer that was sent originally to the
fw. Do that only if it was request by the user since very
few flows need to get the HCMD sent in the response handler.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The generic part of the driver now creates all debugfs
directories. It creates a root directory directly in
the the root of the debugfs filesystem and within that
directories for each device, named after the device ID
of the devices iwlwifi is attached to.

In the cfg80211/mac80211 directory there's now a link
to the toplevel iwlwifi debugfs directory to make it
easier to find the debugfs files.
Signed-off-by: NMeenakshi Venkataraman <meenakshi.venkataraman@intel.com>
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since the kmem cache API doesn't internally allocate
the name but just points to the name that was passed
in we can't use stack memory for it. Move the name
into the transport struct.
Reported-by: NStanislaw Gruszka <sgruszka@redhat.com>
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since the op_mode defines the queue mapping, let it do it
completely through the API functions.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Different transports will have different needs: New tranports
need headroom for their own use before the Tx cmd. So allocate
the Tx cmd pool in the transport and give it a unique name
based on dev_name.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

We need to be able to enable / disable Tx queues in HW
dynamically. So this function is no longer related to AGG
only. It can do the job for any queue, even AC ones. Change
the name to better reflect its role.

Also use the new function to configure the AC / CMD queues
in tx_start.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

We need to be able to enable / disable Tx queues in HW
dynamically. So this function is no longer related to AGG
only. It can do the job for any queue, even AC ones. Change
the name to better reflect its role.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This is common, not uCode API specific, so move
it to the transport together with the command
header struct definition.
Reviewed-by: NMeenakshi Venkataraman <meenakshi.venkataraman@intel.com>
Reviewed-by: NGuy Cohen <guy.cohen@intel.com>
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This macro is needed by other transports besides PCIe, thus
moving to a common location.
Signed-off-by: NGregory Greenman <gregory.greenman@intel.com>
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Reviewed-by: NWey-Yi W Guy <wey-yi.w.guy@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

By default, iwlwifi uses order-1 pages (8 KB) to store incoming frames,
but doesnt say so in skb->truesize.

This makes very possible to exhaust kernel memory since these skb evade
normal socket memory accounting.

As struct ieee80211_hdr is going to be pulled before calling IP stack,
there is no need to use dev_alloc_skb() to reserve NET_SKB_PAD bytes.
alloc_skb() is ok in this driver, allowing more tailroom.

Pull beginning of frame in skb header, in the hope we can reuse order-1
pages in the driver immediately for small frames and reduce their
truesize to the minimum (linear skbs)
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Since the transport allocates and frees itself in
the transport specific code, there's no need for
virtual functions for it. Remove the free method
and call the correct functions directly.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>

That file is now holding just a few defines and
the module parameters, so it shouldn't include
anything. Make sure the right users include the
right files instead.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>

Since the op_mode may go away, the transport needs to be able to
be told not to update the op_mode at all (even for RF kill).
Provide this API and use it in the proper places.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>

Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>

It is not needed any more.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>

Instead of using the shared area that we be killed.
Remove the pointer to config from shared since it is not
used any more.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>

The command strings are needed through the layers for
debug and error messages, but can differ with opmode.
As a result, we need to give the command names to the
transport layer as configuration.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>

The whole code around eeprom is distributed
across whole bunch of different files, most
of which belong to the to-be-DVM code. As a
result, it is currently very hard to split
out the EEPROM code to be generic. However,
it is also quite unlikely that the current
EEPROM code will be needed by the MVM code
as that has different mechanisms to query
the EEPROM (it does so through the uCode.)

So, at least temporarily, move everything
into priv. If it becomes necessary to use
the code from MVM, we will have to split it
out, but then it's also easier since we'll
know what pieces we need.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>