[U-Boot-Users] start.S code snippet doubt

[Wolfgang Denk]

In message <1101131529.23c64d7cnishant.subs at myrealbox.com> you wrote:
> 
> What does the following code achieve: (Code snippet from start.S)

Which start.S? There are at least 25 files with this name.

> boot_cold:
> #if defined(CONFIG_MPC8260ADS)
> 	lis	r3, CFG_DEFAULT_IMMR at h
> 	nop
> 	lwz	r4, 0(r3)
> 	nop
> 	rlwinm	r4, r4, 0, 8, 5
> 	nop
> 	oris	r4, r4, 0x0200
> 	nop
> 	stw	r4, 0(r3)
> 	nop
> #endif /* CONFIG_MPC8260ADS */

Did  you  try  to  understand  what  the  code  is  doing?  And  what
CFG_DEFAULT_IMMR might mean?

> Can anyone please tell me the importance/significance of this code? 

The code is very important and significant - without it  U-Boot  will
not run on this board.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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well  schooled in machine language, since it is a fundamental part of
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