lkml.org 
[lkml]   [2008]   [Sep]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Regression in 2.6.27 caused by commit bfc0f59


On Wed, 3 Sep 2008, Thomas Gleixner wrote:
>
> Except for the couple of exceptions, where the readout of the old PIT
> timer is broken. See arch/x86/kernel/i8253.c:pit_read()

Well, the VIA problem, for example, is not an issue if you just make it do
the maximum timeout (ie count down from zero), which is what you want
_anyway_ in order to get the maximum range.

So that one is simply avoided by just programming the timer to count the
maximum possible range.

However, the counter latching itself does seem to stop the counting until
it is read, which is rather irritating. It means that you can't just latch
and read in a tight loop. An while I actually have a patch that works very
well for me, it depends on not latching, which is not strictly correct
either.

So yeah, I suspect using the current code and trying to just see when it
isn't reliable (and the "max time" seems good for that) is probably the
best option.

Linus


\
 
 \ /
  Last update: 2008-09-03 03:55    [W:0.081 / U:1.080 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site