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Date:   Wed, 25 Nov 2009 21:34:50 +1000
From:   Adam Nielsen <a.nielsen@shikadi.net>
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Subject: Re: Can you add a signature to the kernel ELF image?
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> Take a look at arch/mips/kernel/head.S.  This file will be the first on
> the final linker call's command line, that is head.S's .text section will
> end at the lowest address.

Ah excellent, that combined with the linker script (to twiddle load addresses) 
is just what I'm after.

> #ifdef CONFIG_NCD_HMX
> 	b	1f
> 	nop
> 	nop
> 	.word	0x20
> 	.asciz	"XncdHMX"
> 	.word	0, 0, 0
> #endif

Perfect, thanks for the example, that makes it much easier.

>> [1] http://www.linux-mips.org/wiki/HMX
>
> The wiki page says something about a CRC but just poking a 0x20 into a
> constant address is not exactly a CRC calculation.  Not sure how this
> really is meant.

As far as I'm aware 0x20 means "ignore the CRC", I think the CRC itself is 
covered by one of the zero words.

Cheers,
Adam.