[patch 06/10] 40x decrementer fixes

Sergei Shtylyov sshtylyov at ru.mvista.com
Sat Aug 4 03:10:19 EST 2007


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




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