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Date: Fri, 03 Aug 2007 21:10:19 +0400
From: Sergei Shtylyov <sshtylyov@ru.mvista.com>
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To: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Subject: Re: [patch 06/10] 40x decrementer fixes
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I wrote:

>>Allow generic_calibrate_decr to work for 40x platforms.  Given that the hardware
>>behavior is identical, this also changes the set_dec function to reload the PIT

    It's not actually identical. When you're writing to the PIT reg on 40x, 
you're alos writing to the hidden PIT auto-reload reg. which is not the case 
for 440 that is true Book E.

>>on 40x to match the behavior 44x currently has.

>     Why bother doing this?! This will only warrant you imprecise decrementer 
> interrupts while it should be interrupting at the precise period currently (if 
> you load PIT once)...

    I.e. the error will only accumulate. NAK.

WBR, Sergei