public inbox for linux-acpi@vger.kernel.org
 help / color / mirror / Atom feed
* dummy read after reading p_lvl2?
@ 2003-10-05 18:21 Nate Lawson
  0 siblings, 0 replies; only message in thread
From: Nate Lawson @ 2003-10-05 18:21 UTC (permalink / raw)
  To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f; +Cc: Paul Diefenbaugh

I noticed that the processor.c driver does a dummy read of the xtimer
register after a read of p_lvl2 or p_lvl3.  Why is this?  Is there some
kind of delay slot that is never executed?  The spec is very thin on this
area.  Also, how long does it take to enter level 2 or 3 after the read
from the p_lvlX register?  The spec says on the same clock cycle but I
wonder if it means cpu clock or acpi timer clock.

I've written a Cx driver for FreeBSD and it appears to work although I
need to measure power consumption to be sure.

Thanks,
Nate


-------------------------------------------------------
This sf.net email is sponsored by:ThinkGeek
Welcome to geek heaven.
http://thinkgeek.com/sf

^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2003-10-05 18:21 UTC | newest]

Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2003-10-05 18:21 dummy read after reading p_lvl2? Nate Lawson

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox