The rules turn out to be:
* for non-aggregation session TX queues - it's either sent or not sent.
* for aggregation session TX queues - if nframes=1, then the status reflects
the completed transmission.
* however, for nframes > 1, then this is just a status reflecting what
the initial transmission did. The compressed BA (immediate or delayed)
may not have yet been received, so the actual frame status is in the
compressed BA updates.
Whilst here, I fiddled with debugging and formatting a bit.
There's also RTS attempts (what the atheros chips call "short retries")
which weren't being logged and they aren't yet being used in the rate
control statistics updates. For now, at least log them.
TODO:
* This still isn't 100% correct! So I have to tinker with this some more.
(The failures aren't always failures..)
* Extend the rate control API in net80211 so it can take both short and
long retry counts.
Tested:
* Intel 5100, STA mode
The (eventual) intention is to create MIB counters for transmitted
frame completion to count how many packets with each status are
transmitted.
Note the difference between A-MPDU and non A-MPDU status.
Obtained from: Linux iwlwifi/dvm driver
but has some retries.
Without this, single frame transmission in AMPDU will always look like
it succeeded fine, and thus AMRR will think it's totally fine to just
keep upping the rate upwards.
Now, this is still not quite right! For multi-frame aggregates the
completion happens in two parts - the TX done and the BA received.
The driver is currently double accounting those a little - there's no
way to say to the rate control code "I completed X frames, Y worked fine,
there were Z retries." And it's a bit odd with iwn, as the firmware
retransmits frames for us so we don't get to see how many retransmits
happened; only that it took longer than normal. I may have to extend
the rate control API to properly track that.
So this may keep the rate lower than it should be, but that's better
than keeping it higher than it should be.
Tested:
* 5100, STA mode
in preparation for the 5300 3x3 NIC.
During this particular adventure, I did indeed discover that a whole
swath of things made little to no sense.
Those included, and are fixed here:
* A lot of the antenna configuration bits assume the NIC has two receive
chains. That's blatantly untrue for NICs that don't.
* There was some disconnect between the antenna configuration when
forming a PLCP rate DWORD (which includes the transmit antenna
configuration), separate to the link quality antenna configuration.
So now there's helper functions to return which antenna configurations
to use and those are used wherever an antenna config is required.
* The 5300 does up to three stream TX/RX (so MCS0->23), however
the link quality table has only 16 slots. This means all of the
rate entries are .. well, dual-stream rates. If this is the case,
the "last MIMO" parameter can't be 16 or it panics the firmware.
Set it to 15.
* .. and since yes it has 16 slots, it only would try retransmitting
from MCS8->MCS23, which can be quite .. terrible. Hard-code the last
two retry slots to be the lowest configured rate.
* I noticed some transmit configuration command stuff is different
based on firmware API version, so I lifted that code from Linux.
* Add / augment some more logging to make it easier to capture this
stuff.
Now, 3x3 is still terrible because the link quality configuration is
plainly not good enough. I'll have to think about that.
However, the original goal of this - 3x3 operation on the Intel
5300 NIC - actually worked.
There are also rate control bugs in the way this driver handles
notifying the net80211 rate control code when AMPDU is enabled.
It always steps the rate up to the maximum rate possible - and
this eventually ends in much sadness. I'll fix that later.
As a side note - 2GHz HT40 now works on all the NICs I have tested.
As a second side note - this exposed some bad 3x3 behaviour in
the ath(4) rate control code where it starts off at a 3-stream rate
and doesn't downgrade quickly enough. This makes the initial
dhcp exchange take a long time. I'll fix the ath(4) rate code
to start at a low fixed 1x1 MCS rate and step up if everything
works out.
Tested:
* Intel 2200
* Intel 2230
* Intel 5300
* Intel 5100
* Intel 6205
* Intel 100
TODO:
* Test the other NICs more thoroughly!
Thank you to Michael Kosarev <russiane39@gmail.com> for donating the
Intel 5300 NIC and pestering me about it since last year to try and
make it all work.
"fatal firmware error" happens. Previously it was neccessary to reset
it manually, using "/etc/rc.d/netif restart".
Approved by: adrian@
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
"fatal firmware error" happens. Previously it was neccessary to reset
it manually, using "/etc/rc.d/netif restart".
Approved by: adrian@
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Centrino 2230 firmware.
This fixes the general statistics block to be actually valid.
I've verified this by contrasting the output of iwnstats before and
after the change. The general block is now correct.
Tested:
* Intel 5100 (old format stats message)
* Intel 2230 (new format stats message)
It turns out that there's a variant format of the RX statisitcs notification
from the intel firmware. It's even more whacked - the non-BT variant has
bluetooth fields; apparently some later NICs return even _more_ bluetooth
related fields.
I'll commit the statistics structure changes here - it's a no-op for the
driver. I'll later teach the driver code to populate a statistics structure
from the received message after reformatting things correctly.
I don't _think_ it's going to fix anything related to sensitivity programming
as the CCK/OFDM (non-11n) fields are in the same place for both formats.
But the HT structure and the general statistics aren't in the same place.
I'll go find some NIC(s) that spit out the other format and when I find one,
I'll go and update the driver to handle things correctly.
Tested:
* Intel 5100 (which returns the legacy, non-BT format)
Obtained from: Linux iwlwifi
The origin of WEP comes from IEEE Std 802.11-1997 where it defines
whether the frame body of MAC frame has been encrypted using WEP
algorithm or not.
IEEE Std. 802.11-2007 changes WEP to Protected Frame, indicates
whether the frame is protected by a cryptographic encapsulation
algorithm.
Reviewed by: adrian, rpaulo
- Simplify MSI allocation and release. For a single one, we don't need to
fiddle with the MSI count and pci_release_msi(9) is smart enough to just
do nothing in case of INTx.
- Don't allocate MSI as RF_SHAREABLE.
- Use DEVMETHOD_END.
- Use NULL instead of 0 for pointers.
MFC after: 1 week
This chip doesn't require the temperature sensor offset, either v1 or
v2. Doing so causes the initial calibration test to fail.
Tested:
* Intel Centrino 6150
Make the scan state optional - we'll obviously need a vap, but we now
won't require the scan state. the only thing the scan state is needed
for is to check for the list of SSIDs to scan - which we can now
just plain ignore by passing in NULL as the scan state pointer.
Tested:
* Intel 5100 (STA)
This is in preparation for being able to use iwn_scan() to do an off
channel scan to reset the RF tuning.
It should be a no-op.
Tested:
* Intel 5100 (STA)
in preparation for the scan based retune logic.
The linux iwlwifi driver does a rescan (onto a non-active channel)
to force an RF retune when the PLCP error rates exceed a certain threshold.
* Add code to track HT PLCP rate errors;
* Separate out the PLCP error count fetch and update so the delta
can be used when checking for PLCP error rates;
* Implement the PLCP error logic from iwlwifi;
* For now, just print out whenever the error rate exceeds the
threshold.
The actual scan based retune will take a bit more effort; the scan
command code right now assumes that a scan state is passed in.
This does need to change to be more flexible (both for this and
in preparation for scanning multiple channels at once.)
Tested:
* 5100 (STA mode)
* 2200 (STA mode)
* 2230 (STA mode)
working on some RF tuning issues.
The linux iwlwifi driver has these thresholds which they use to see
if there are PLCP errors over a certain interval. If they hit this,
they trigger a single-channel (different from active channels!)
scan to retune the RF front-end.
for these chipsets.
* Correctly set the active/passive flag in the scan request - this is
NOT a "is the channel active|passive"; it's to do with whether we
have an SSID to actively scan for or not. The firmware takes care
of the active/passive setup of the channel.
* Calculate the active/passive dwell time based on the beacon interval
and the channel mode, rather than using a hard coded value.
* For now, hardcode the scan service_time. It's defined as:
31:22 - number of beacon intervals to come back onto the home channel
for;
0:21 - time (microseconds) to come back onto the home channel for.
When doing an active scan when the NIC is active (whether we're associated
or not - it only matters if we've setup the NIC to a destination or not)
this determines how much time to stay on the home channel for when
scanning. We can tune this based on the amount of active traffic.
For now it's 4 beacon intervals and 100 microseconds.
* Fix the "good crc threshold" setting. It differs based on the NIC
firmware. Some older firmware required a workaround; the later
firmware instead treats the field as a flag.
* Enforce that we are not sending a scan command if one is already
pending. Any time this is done is a bug and it absolutely needs
to be fixed - so be very loud.
* Add the SCAN flag to a few debug messages that are scan related but
only occuring under STATE.
Now, this does get noisy when you're scanning in an actively busy 2GHz
network as the firmware (for reason I don't quite yet understand) seems
hell bent on staying on some passive channels longer than it should.
However, it should eventually recover and complete the scan.
This is a work in progress; please let me know if things get stuck or
if things improve!
Tested:
* intel centrino 2200
* intel centrino 2230
* intel 6200
* intel 5100
* intel 4965 (gets upset, but that's a known issue)
Obtained from: linux iwlwifi
TX ring according to what the firmware requires.
The firmware requires A-MPDU sub-frames to be at a very specific ring
offset - that is, the ring slot offset should be (seqno % 256.)
This holds for every NIC I've tested thus far except the 4965,
which starts erroring out here shortly before the firmware panics.
Which is good, it's doing what it's supposed to (read: capture that
we've screwed up somewhere.)
The specifics about getting this stuff right:
* the initial seqno allocation should match up with the ringid.
* .. yes, this means we can start at a ring offset that isn't zero.
* .. because we program the start seqno in the firmware message
to setup the AC.
* The initial seqno allocation may be non-zero _and_ frames may be
being transmitted during a-mpdu negotiation. I faced similar
issues on ath(4) and had to software queue frames to that node+TID
during A-MPDU negotiation.
* seqno allocation should be in lockstep with ring increments.
* If we fail to transmit some segment, no, we shouldn't reuse that
ring slot. We should just transmit a BAR (which we aren't yet
doing, sigh) and move onto the next seqno.
* In theory there shouldn't be any holes in the seqno space when
we are transmitting frames.
Tested:
* 4965 (throws problems, so yes we have to fix this);
* 5100 (seems ok);
* 6200 (seems ok);
* 2200 (seems ok);
* 2230 (seems ok).
shifts into the sign bit. Instead use (1U << 31) which gets the
expected result.
This fix is not ideal as it assumes a 32 bit int, but does fix the issue
for most cases.
A similar change was made in OpenBSD.
Discussed with: -arch, rdivacky
Reviewed by: cperciva
This field needs to be (a) set, and (b) greater than the other timeouts
(passive, active, maxquiet, etc.) It also is in microseconds, not
milliseconds.
I hope this will fix the scan hangs that people are seeing.
Obtained from: Linux iwlwifi
