Re: [PATCH]: Remove CONFIG_BUILD_ELF64 entirely

[Kumba <kumba@gentoo.org>]

Atsushi Nemoto wrote:
> Hmm... really strange.
> 
> This is OK:
> 		lui	k1, %highest(kernelsp)
> 		daddiu	k1, %higher(kernelsp)
> 		dsll	k1, k1, 16
> 		daddiu	k1, %hi(kernelsp)
> 		dsll	k1, k1, 16
> 
> This is NG:
> 		lui	k1, %hi(kernelsp)
> 
> So, could you try this one?
> 
> 		nop
> 		nop
> 		nop
> 		nop
> 		lui	k1, %hi(kernelsp)
> 
> If it booted, the problem should be in something irrelevant place.
> I.e. this optimization just triggers other bug by code/data movement.

Yup, it booted.  On further testing at iluxa's behest, it turns out it may be 
some quirk/cpu errata related to the RM5200 I use in my O2.  I swapped it out 
for a plain R5000 @ 200MHz, and removed the nop's -- boots fine.

This may also explain why the cobalt's were hitting something odd.  They also 
use a member of the RM52xx family (RM5231 iirc, O2 uses an RM5261).


--Kumba

-- 
Gentoo/MIPS Team Lead

"Such is oft the course of deeds that move the wheels of the world: small hands 
do them because they must, while the eyes of the great are elsewhere."  --Elrond