iwn fails to scan on E6330

Mon Nov 24 14:12:38 UTC 2014

Hi all,

I have to say, the BSD world is quite new to me. It peeked my interest
long time ago, but a week a ago I was brave enough to give it a try on a
real physical box. A Latitude E6330.

In general the installation was straight forward. For now I just face
troubles with GPT (another topic) and iwn.

Here is what my machine has:
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root at zam709:~ # pciconf -lv iwn0
iwn0 at pci0:2:0:0:    class=0x028000 card=0x13218086 chip=0x00828086 rev=0x34 hdr=0x00
    vendor     = 'Intel Corporation'
    device     = 'Centrino Advanced-N 6205 [Taylor Peak]'
    class      = network

root at zam709 ~ 0
59 # kldstat -v | grep iwn
    158 pci/iwn
17    1 0xffffffff820cc000 52db4    iwn1000fw.ko (/boot/kernel/iwn1000fw.ko)
    509 iwn1000fw_fw
18    1 0xffffffff8211f000 ad28f    iwn2030fw.ko (/boot/kernel/iwn2030fw.ko)
    510 iwn2030fw_fw
19    1 0xffffffff821cd000 2e58a    iwn4965fw.ko (/boot/kernel/iwn4965fw.ko)
    511 iwn4965fw_fw
20    1 0xffffffff821fc000 53a21    iwn5000fw.ko (/boot/kernel/iwn5000fw.ko)
    512 iwn5000fw_fw
21    1 0xffffffff82250000 52d42    iwn5150fw.ko (/boot/kernel/iwn5150fw.ko)
    513 iwn5150fw_fw
22    1 0xffffffff822a3000 6f71e    iwn6000fw.ko (/boot/kernel/iwn6000fw.ko)
    514 iwn6000fw_fw
23    1 0xffffffff82313000 a5d05    iwn6000g2afw.ko (/boot/kernel/iwn6000g2afw.ko)
    515 iwn6000g2afw_fw
24    1 0xffffffff823b9000 70fc2    iwn6000g2bfw.ko (/boot/kernel/iwn6000g2bfw.ko)
    516 iwn6000g2bfw_fw
25    1 0xffffffff8242a000 73265    iwn6050fw.ko (/boot/kernel/iwn6050fw.ko)

root at zam709:~ # ifconfig iwn0
iwn0: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 2290
  ether 6c:88:14:18:fb:d0
  nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
  media: IEEE 802.11 Wireless Ethernet autoselect (autoselect)
  status: no carrier

root at zam709:~ # time ifconfig iwn0 up scan
ifconfig: unable to get scan results
0.007u 0.028s 0:00.03 66.6% 370+400k 2+0io 0pf+0w

root at zam709:~ # uname -a
FreeBSD zam709 10.1-RELEASE FreeBSD 10.1-RELEASE #0 r274401: Tue Nov 11 21:02:49 UTC 2014
root at releng1.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64
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>From the logs above you can see that the kernel has a built in module
for iwn and the firmwares are loaded. The kernel sees the interface and
I can bring it up.  But when trying to scan for available BSSs, the scan
command return immediately without success (exit 1).

Right now I suspect the firmware is somehow wrongly configured. But I
cannot find any logs about firmwares in the logs. 

  Q: What is the proper procedure to debug a startup of the iwn module?

Coming from the linux administration, I failed to gain knowledge how the
firmware is handeled. I tried to enable different sets of firmware
which were to enable just single firmware and up to enable all availabel
firmwares. I used kldload/unload for this.

  Q: When are the firmwares getting effectively used? Meaning, how does
  dynamically loading/unloading a firmware change the bahaviour of the
  module?
   or
  When does a module expect a firmware to be available and does it
  accepts a runtime cahnge of the firmware?

  Q: As the iwn module is compiled into the kernel, how can I restart
  this inorder it might read in the firmware again?