[U-Boot-Users] Re: [PATCH] 8xx: fix initialation bug/race condition between u-boot & linux

Jaap-Jan Boor jjboor at aimsys.nl
Wed Jun 18 10:32:29 CEST 2003


Hi Wolfgang,

Wolfgang Denk wrote:
> 
> In message <3EF00E16.3050604 at intracom.gr> you wrote:
> >
> >   I think it's just proper defensive programming to always
> > do a CP reset in that case, and as soon as possible.
> 
> Then probably the boot loader should do it before starting the  Linux
> kernel.

This would be a mostly hidden requirement for any boot loader towards
the ppc linux kernel. 

> 
> > The best thing we could do is do the reset at head_8xx.S.
> 
> Note that such a change will kill all attempts for ealy debug  output
> over the serial console port.

That would also be the case when the boot loader does it. The kernel
will initialize the uart again very early isn't it?
And is a CP reset enough? I think I remember you also have to unlock
the pram section that is used for uCode.

just some thoughts,

Jaap-Jan

> 
> Wolfgang Denk
> 
> --
> Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
> Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
> The one who says it cannot be done should never interrupt the one who
> is doing it.
> 
> ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

-- 
J.G.J. Boor			  Anton Philipsweg 1
Software Engineer		  1223 KZ Hilversum
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