SDIO and DHCP

[Dan Williams]

On Tue, 2008-12-16 at 13:27 -0500, Jeff Sutherland wrote:
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> On Tuesday 16 December 2008, Simon Twogood wrote:
> > Hell everyone,
> >
> > I've been having success using the a Libertas SDIO module with Linux
> > 2.6.27, but only with static IP addresses. My board is an Atmel
> > AT91SAM9263. Has anyone had success obtaining an IP address through
> > DHCP on a similar board, or any other board for that matter?
> >
> > I found a old thread that mentions a similar problem here
> > http://lists.infradead.org/pipermail/libertas-dev/2008-May/001526.html ,
> > but it seems it was unresolved.
> >
> > My firmware version is 9.70.3p24. Here's a sample of the the procedure
> > I use to reproduce my error:
> >
> >
> > root at mydevice:~$ modprobe libertas_sdio
> > libertas_sdio: Libertas SDIO driver
> > libertas_sdio: Copyright Pierre Ossman
> > firmware: requesting sd8686_helper.bin
> > firmware: requesting sd8686.bin
> > libertas: 00:19:88:05:11:56, fw 9.70.3p24, cap 0x00000303
> > libertas: PREP_CMD: command 0x00a3 failed: 2
> > libertas: PREP_CMD: command 0x00a3 failed: 2
> > libertas: eth1: Marvell WLAN 802.11 adapter
> >
> > root at mydevice:~$ ifconfig eth1 up
> >
> > root at mydevice:~$ iwlist eth1 scan
> > eth1      Scan completed :
> >            Cell 01 - Address: 00:21:29:71:19:E8
> >                      ESSID:"emptynetwork"
> >                      Mode:Managed
> >                      Frequency:2.437 GHz (Channel 6)
> >                      Quality=92/100  Signal level=-58 dBm  Noise
> > level=-96 dBm
> >                      Encryption key:off
> >                      Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18
> > Mb/s
> >                                24 Mb/s; 36 Mb/s; 54 Mb/s; 6 Mb/s; 9 Mb/s
> >                                12 Mb/s; 48 Mb/s
> >
> > root at mydevice:~$ iwconfig eth1 essid emptynetwork
> >
> > root at mydevice:~$ udhcpc -H mydevice -i eth1
> > udhcpc (v1.2.1) started
> > Sending discover...
> > Sending discover...
> > Sending discover...
> > ------------[ cut here ]------------
> > WARNING: at net/sched/sch_generic.c:219 dev_watchdog+0x154/0x240()
> > NETDEV WATCHDOG: eth1 (libertas_sdio): transmit timed out
> > Modules linked in: libertas_sdio libertas at91_mci
> > [<c0025fa0>] (dump_stack+0x0/0x14) from [<c003822c>] (warn_slowpath
> > +0x64/0x80)
> > [<c00381c8>] (warn_slowpath+0x0/0x80) from [<c0180b0c>] (dev_watchdog
> > +0x154/0x240)
> >   r3:c394c000 r2:c0238d80
> >   r6:c01809b8 r5:c394c000 r4:c027ef34
> > [<c01809b8>] (dev_watchdog+0x0/0x240) from [<c0041440>]
> > (run_timer_softirq+0x150/0x1e8)
> >   r6:c01809b8 r5:00000100 r4:c026f740
> > [<c00412f0>] (run_timer_softirq+0x0/0x1e8) from [<c003cf08>]
> > (__do_softirq+0x60/0xc8)
> >   r7:c0255c80 r6:0000000a r5:c026f544 r4:00000001
> > [<c003cea8>] (__do_softirq+0x0/0xc8) from [<c003d258>] (irq_exit
> > +0x48/0x50)
> >   r7:c0255c80 r6:00000000 r5:c0259ea4 r4:00000001
> > [<c003d210>] (irq_exit+0x0/0x50) from [<c0021054>]
> > (__exception_text_start+0x54/0x6c)
> > [<c0021000>] (__exception_text_start+0x0/0x6c) from [<c0021834>]
> > (__irq_svc+0x34/0x60)
> > Exception stack(0xc0253f50 to 0xc0253f98)
> > 3f40:                                     00000000 0005317f 0005217f
> > 60000013
> > 3f60: c0023270 c0252000 c001eee8 c0255c80 2001d32c 41069265 2001d2f8
> > c0253fa4
> > 3f80: 600000d3 c0253f98 c00232b8 c00232c4 60000013 ffffffff
> >   r7:c0255c80 r6:00000001 r5:fefff000 r4:ffffffff
> > [<c0023270>] (default_idle+0x0/0x5c) from [<c002314c>] (cpu_idle+0x3c/
> > 0x58)
> > [<c0023110>] (cpu_idle+0x0/0x58) from [<c01d6610>] (rest_init+0x58/0x6c)
> >   r5:c0269e10 r4:c0271f88
> > [<c01d65b8>] (rest_init+0x0/0x6c) from [<c0008bc8>] (start_kernel
> > +0x284/0x2dc)
> > [<c0008944>] (start_kernel+0x0/0x2dc) from [<20008034>] (0x20008034)
> >   r5:c026a320 r4:00053175
> > ---[ end trace 4093a6ca7302871d ]---
> > libertas: tx watch dog timeout
> > Sending select for 192.168.5.128...
> > Sending select for 192.168.5.128...
> > Sending select for 192.168.5.128...
> > libertas: tx watch dog timeout
> > Sending discover...
> > Sending discover...
> > libertas: tx watch dog timeout
> > Sending discover...
> > libertas: tx watch dog timeout
> > libertas: tx watch dog timeout
> > libertas: tx watch dog timeout
> > libertas: tx watch dog timeout
> > Sending select for 192.168.5.128...
> > Sending select for 192.168.5.128...
> > Sending select for 192.168.5.128...
> > libertas: tx watch dog timeout
> > Sending discover...
> > Sending discover...
> 
> Please try one thing and let us know how you get on: turn on all the debugging 
> for the wifi subsystem and libertas module and try again.  This looks 
> suspiciously like a problem I encountered with this chipset on another 
> platform.

Yeah, in general this stuff is highly controller-dependent; there are
some comments in if_sdio about that sort of thing.  Some controllers
don't really support reads of certain byte widths, others require random
alignments, etc.  I've usually tested libertas_sdio on an generic laptop
Ricoh SD/MMC controller and that normally works well, but we certainly
had to quirk a few things for the OLPC "Cafe" SD controller.  Also make
sure you're using a fairly recent kernel (2.6.26 if possible) since
there have been fixes to the SDIO stack itself in the kernel since it
got merged in 2.6.24.

Dan