[FOUND}: CPU Cx states not working with recent kernel on Thinkpad

[Taku YAMAMOTO]

On Tue, 13 Jul 2004 14:23:13 +0200
Andrea Campi <andrea at webcom.it> wrote:
> Hi,
> 
> On Tue, Jul 06, 2004 at 10:42:05AM +0200, Andrea Campi wrote:
> > I upgraded my Thinkpad 570E from a beginning of June kernel to new
> > sources cvsup'd after the recent changes (ACPICA import etc) a couple
> > of days ago. I now get this:
> > 
> > ...
> > cpu0: <ACPI CPU (3 Cx states)> port 0x530-0x537 on acpi0
> > cpu0: Failed to attach throttling P_CNT
> 
> I was able to determine this issue appeared with acpi.c rev 1.159 and
> related ("Add support to ACPI to manage its own resources."). Looking
> at devinfo -vr before and after the commit (see below) seems to
> confirm that something changed, although I can't understand how that
> caused the breakage. In fact, all the involved I/O ports are not
> reserved by any acpi_sysresource*, so I have no idea where to go
> from here.
> 
> Nate (or anybody else), any idea?

I suspect it's because acpi_timer0 gets attached and sits on
not-yet-managed resources before acpi_sysresource0 reserves
resources for later use.

We can confirm that by temporarily disabling acpi_timer by
debug.acpi.disabled="timer" to see the working acpi_cpu.

Can we defer the attachment of acpi_timer0 after acpi_sysresource?

-- 
-|-__    YAMAMOTO, Taku
 | __ <	    <taku at tackymt.homeip.net>