Porting Fiasco+L4re to DaVinci DA850 - prefetch abort in sigma0

Adam Lackorzynski adam at os.inf.tu-dresden.de
Wed May 14 02:00:38 CEST 2014


On Tue May 13, 2014 at 16:48:58 +1000, Peter Howard wrote:
> I'm trying to port Fiasco to the DA850.  I'm basing this on the
> 2014022818 snapshot.  I've gotten to the point where I've modified the
> configuration for both fiasco and l4re, added the BSP and bootstrap
> platform files, and added the extra drivers I need to get started.  I
> can build an image to load on the machine and it boots through the
> kernel fine.  Then it tries to run sigma0 and gets a prefetch abort:
> EXCEPTION: prefetch abort pfa=c0090100, error=0033000d                         
> R[0]: c0002000 00000000 00000000 00000000  00000000 00000000 00000000 00000000 
> R[8]: 00000000 00000000 00000000 00000000  00000000 c1013de4 04080124 c0090100 
> (note, I'm including the full boot output at the end of the email)
> The address, c0090100, is correct as the entry point for sigma0.
> Now, if I'm reading the FSR right, that's indicating a permission error
> on the section.  But nothing I've added/changed has anything to do with
> the MMU/mapping.  As far as I can see, that's all straight armv5 code,
> with nothing special to the board (which uses an arm926ejs core).
> So any idea why sigma0 would be getting mappings with the wrong
> permission?

Since RAM starts at 3GB physically, I'm wondering whether you set the
'kern_start_0xd' preprocessor tag in your Modules bsp-file
(PREPROCESS_PARTS += kern_start_0xd)?

Adam                 adam at os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/

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