Re: [Madwifi-devel] ath_hal_reset() crashing on BE platform

[Garrett D'A. <gar...@ta...>]

Hani Mustafa wrote:
> This problem seems suspiciously similar to: http://madwifi.org/ticket/574
>
> Interestingly, when using the HAL available with madwifi-0.9.0, the
> illegal address accessed is 0x1f as opposed to 0x0.
>
> Hope this lights a few bulbs ;-)
>
> ~Hani Mustafa
>
>
> On Sep 10, 2006, at 03:16 PM, Hani Mustafa wrote:
>
>> Hail folks,
>>
>> I'm trying to use the HAL on an embedded system (that is not *nix
>> based). The system is running on a big endian PPC processor.
>>
>> First off, I had some trouble doing an attach() and basically had to
>> make do without any kind of byteswapping. I believe the HAL assumes
>> that all PCI controllers on big endian systems are set to
>> automatically do BE-to-LE bswapping.

The HAL is "weird".   Some things are byte swapped, some aren't. 
Certainly PCI configuration space is byte swapped.  But register
accesses should probably not be.

The AP30 WiSoC is certainly big-endian, as is SPARC, and those both work
fine.  I'd take a look at the NetBSD code for those platforms.


    -- Garrett
>>
>> After having done that, ath_hal_reset/ah_setPCUConfig cause the system
>> to crash with an access to memory zero exception from within the hal:
>> -----
>> Data TLB miss (DMISS)           : 0x00000000 (illegal addr. accessed)
>>
>> 0x10740c1c [0x10740ba0   zz0b69b07c] , + offset 0x7c (124)
>> 0x1073b4dc [0x1073b384   zz0002dbd2] , + offset 0x158 (344)
>> 0x10724f30 [0x10724e58   atheros_reset] , + offset 0xd8 (216)
>> ------
>>
>> Between the attach and the reset, I have called:
>>
>> 1) ath_hal_getwirelessmodes
>> 2) ath_hal_init_channels
>> 3) ah_getRateTable
>> 4) ah_setDefAntenna
>> 5) ah_getMacAddress
>> 6) setup txqueues for DATA, CAB, and BEACON
>> 7) set an rx filter
>> 8) get/set Bssid mask
>>
>> Am I missing something? Could this be an endianness issue? Or am I
>> missing a function call somewhere?
>>
>> Cheers!
>>
>> ~Hani Mustafa


-- 
Garrett D'Amore, Principal Software Engineer
Tadpole Computer / Computing Technologies Division,
General Dynamics C4 Systems
http://www.tadpolecomputer.com/
Phone: 951 325-2134  Fax: 951 325-2191