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

[Nishant Galange]

Hi all,

What does the following code achieve: (Code snippet from start.S)
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 */

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

Regards,
Nishant