i386/104678: SMP not working on Turion XP Laptop

[Bruce Evans]

The following reply was made to PR i386/104678; it has been noted by GNATS.

From: Bruce Evans <bde at zeta.org.au>
To: Andrew Pantyukhin <infofarmer at freebsd.org>
Cc: freebsd-gnats-submit at freebsd.org
Subject: Re: i386/104678: SMP not working on Turion XP Laptop
Date: Wed, 8 Nov 2006 11:29:06 +1100 (EST)

 On Tue, 7 Nov 2006, Andrew Pantyukhin wrote:
 
 > On 11/7/06, Bruce Evans <bde at zeta.org.au> wrote:
 
 > > On a similar laptop (HP nx6325 Turion X2 2GHz), I found 2 workarounds:
 >
 > I have Fujitsu-Siemens Amilo Pa 1510 Turion X2 TL-56 1.8GHz
 >
 > > 1. Boot with battery power only.  Usually works.
 > > ...
 
 > These workarounds don't work for me. What does work though
 > is keeping CPU loaded (at least one core) with something like
 > "md5</dev/zero" in the background.
 
 Your problem might be quite different, since you have to be able to
 boot to run that.
 
 > Some timings are still of,
 > especially with TSC timecounter, but with i8254 and ACPI-fast
 > it's mostly all right.
 
 The TSC is unlikely to work with more than 1 active CPU.  Both the
 i8254 and ACPI-notslow work OK for me, but very slowly (time for
 reading the counter: i8254: 4-5uS; ACPI-notslow: 1.6-1.7uS).
 
 > Just constantly moving mouse (touchpad) in X also helps.
 
 I have an nfs latency problem where pinging the interface to keep it
 active helps a lot.  Both behaviours would be explained by interrupts
 are getting lost somewhere.
 
 Bruce