[mel-discuss] wireless setup for PandaBoard ?

[Ricardo Anguiano]

Ricardo Anguiano <ricardo_anguiano at mentor.com> writes:
> On 03/01/2012 03:42 PM, Stefan Seefeld wrote:
>> Hello, now that I have successfully the MEL kit on the PandaBoard,
>> I'd like to switch to wireless communication. Are there any simple
>> steps to follow to enable that ? Notably, does the kernel already
>> have all the required modules built in ?
>
> Just to confirm, I don't see that wireless is enabled on any of the
> interfaces:
> 
> [...]
>
> I'll poke around a bit more, but I think the answer is no, there are
> no simple steps to enable wireless out of the box.

Stefan,

I've managed to get wireless enabled by using a different kernel with
the MEL Kit root filesystem on the PandaBoard.

Following these instructions:

     http://elinux.org/Panda_How_to_kernel_3_3_rel

In short:

     1. Get the linux 3.3 kernel sources.

     2. Apply the 0001a-omap4-pandaboard-wlan-fix.patch patch.

     3. Build the kernel and modules and copy them onto the board's boot
        media.

     4. Copy the wireless firmware to the board's root filesystem.

     5. Configure wireless in /etc/wpa_suplicant.conf.

     6. Boot the board.  Note that the kernel argument for the root
     filesystem changed from 'root=/dev/sda2' to 'root=/dev/mmcblk0p2'
     in going from the 2.6 kernel that ships with the MEL Kit to the 3.3
     kernel.  The kernel parameter 'rootdelay=10' was also helpful.

The result is a working wireless network, with some console warning
messages and kernel tracebacks from time to time:

[ 1777.044891] ------------[ cut here ]------------
[ 1777.044891] WARNING: at drivers/net/wireless/wl12xx/rx.c:266 wl12xx_rx+0x3b0/0x490 [wl12xx]()
[ 1777.044891] hlid exceeded WL12XX_MAX_LINKS (66)
[ 1777.067443] Modules linked in: wl12xx wl12xx_sdio
[ 1777.070495] [<c0018750>] (unwind_backtrace+0x0/0xe0) from [<c0037034>] (warn_slowpath_common+0x4c/0x64)
[ 1777.082489] [<c0037034>] (warn_slowpath_common+0x4c/0x64) from [<c00370cc>] (warn_slowpath_fmt+0x2c/0x3c)
[ 1777.082489] [<c00370cc>] (warn_slowpath_fmt+0x2c/0x3c) from [<bf0117dc>] (wl12xx_rx+0x3b0/0x490 [wl12xx])
[ 1777.102844] [<bf0117dc>] (wl12xx_rx+0x3b0/0x490 [wl12xx]) from [<bf00bf1c>] (wl1271_irq+0xdc/0x218 [wl12xx])
[ 1777.113403] [<bf00bf1c>] (wl1271_irq+0xdc/0x218 [wl12xx]) from [<c0089538>] (irq_thread+0xcc/0x1ec)
[ 1777.113403] [<c0089538>] (irq_thread+0xcc/0x1ec) from [<c0053de0>] (kthread+0x80/0x8c)
[ 1777.131378] [<c0053de0>] (kthread+0x80/0x8c) from [<c0012e14>] (kernel_thread_exit+0x0/0x8)
[ 1777.140258] ---[ end trace 87e145887e2adc6f ]---
[ 2772.638458] wl12xx: ERROR exceeded max RX BA sessions
[ 2783.264770] wl12xx: ERROR exceeded max RX BA sessions
[ 2783.338714] wl12xx: ERROR exceeded max RX BA sessions
[ 2810.627136] wl12xx: WARNING corrupted packet in RX with status: 0x1

Keep in mind that this exercise is a proof of concept: Wireless can be
made to work on this board.  People interested in working with and
extending a similar environment themselves should be using the yocto
framework here: http://yoctoproject.org/.  People interested in
commercial support should contact our sales team or visit us on the web:
http://www.mentor.com/embedded-software/linux/.

Thanks,
-- 
Ricardo Anguiano
Mentor Graphics
+1-510-354-6774