[U-Boot-Users] disabling d-cache in 'bootelf' for QNX

[Stefan Roese <sr@denx.de>]

On Thursday 03 January 2008, Rafal Jaworowski wrote:
> >> 1. Does it really hold true that QNX requires d-cache disabled upon
> >> passing control to it?
> >>
> >> 2. If so, this is a custom QNX thing that belongs to do_bootm_qnxelf()
> >> and should be handled there and not at the common ELF handling level.
> >
> > Hmmm. I think that calling applications and especially OS'es is more safe
> > with caches disabled then with caches enabled.
>
> Yeah, after a second thought I tend to agree. Maybe the way to go is doing
> data cache flush from within dcache_disable() properly i.e. bring it in for
> arch variations that don't do it currently like 85xx... Actually to confirm
> my observations I tested a working patch that flushes d-cache at
> cache_disable() just like 86xx and it works for me, this is: my problems
> disappear. Do you think this is a better option?

Yes, I think this is the way to go. Please provide a patch and send it to the 
85xx maintainer. Best would be if you could check the other ARCH's (at least 
PPC) for this dcache_disable() behaviour too.

Thanks.

Best regards,
Stefan

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