mpc8248 SEC -- interrupt handler 'is' invoked

Vikas Aggarwal va824363 at albany.edu
Wed Aug 10 06:52:04 EST 2005


The address returned by kmalloc=0x009ffc5c  is 4 byte aligned.
Are u advicing that dma_map_single() should return 8 byte aligned ,
becuase thats what gets written into the Data-Paclet_descriptor later.

 regards
-vikas

> On Wed, 3 Aug 2005 14:33:26 -0400 (EDT)
> "Vikas Aggarwal" <va824363 at albany.edu> wrote:
>
>> I will try the new BSP but meanwhile like to debug my ported driver.
>>
>> Is there a way , like kernel level single-stepping to know why the
>> "interrupt status register"  gets a value of "0x0000000000000040" which
>> means TEA , transfer error acknowledge.
>
> afaik, TEA usually means memory was unable to be accessed by the sec
> (somewhat along the same lines as a SIGBUS or SIGSEGV).
>
> It's a long shot, but you may want to increase the 4-byte alignment of the
> rng buffer (0x009ffc5c in your trace?) to at least 8-byte.
>
> as for debugging, you can printk sec status registers every time you write
> one, e.g. in a sec register write wrapper fn.  Be sure to check the RNG
> interrupt status register, and the RNG status register, and the RNG
> interrupt control register.
>
> and if all else fails, you can bypass the channel infrastructure
> altogether, and use the RNG EU in slave mode.  Reset the SEC, write the
> RNG Reset Control Register SR bit, write <anyvalue> to the RNG Data size
> register, and pull data off the RNG FIFO at will.
>
> Kim
>





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