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Date: Sun, 25 May 2008 17:32:29 -0700
From: Kevin Diggs <kevdig@hypersurf.com>
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Subject: questions
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Hi,

	In idle_6xx.S one finds instructions like:

	lis   r4,powersave_nap@ha
	lwz   r4,powersave_nap@l(r4)

Can someone explain what this is doing? Presumably the first is loading 
an address and the second a value. What do the '@ha' and '@l' do?

	Also, is there any performance difference between:

	lbz rD,d(rA)
	lhz rD,d(rA)
	lwz rD,d(rA)

	While I'm wasting your time, I picked up an ADB infrared wireless 
keyboard. I think it works. But not under Linux. Should it?

	And is there any reason to prefer one over the other for doing byte 
swapping:

	lwbrx rD,rA,rB
	stwbrx rS,rA,rB

kevin