Re: early printk timings way off

[Tim Bird <tim.bird@am.sony.com>]

Tim Schmielau wrote:
> On Fri, 16 Sep 2005, Tim Schmielau wrote:
> The "Detected 1400.279 MHz processor." line just happens to be written
> _during_ time_init, when use_tsc is already set, but cycles_2_ns is not
> yet initialized.

That's exactly what I surmised as well.  Our e-mails must
have crossed each other.  :-)

> So I think everything is well-understood. It's just a matter of whether 
> it's worth fixing.

Exactly.  My own testing has focused on bootup time measurement.
Historically, the time spent before time_init() has been relatively
small and so I haven't (often) focused on trying to measure it
accurately.  Although, I have done this on occasion to get
complete results.

Andrew's suggestion of a replaceable clock function would
satisfy me.  What do other's think?

 -- Tim

=============================
Tim Bird
Architecture Group Chair, CE Linux Forum
Senior Staff Engineer, Sony Electronics
=============================

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