[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1174479339.10840.59.camel@localhost.localdomain>
Date: Wed, 21 Mar 2007 13:15:38 +0100
From: Thomas Gleixner <tglx@...utronix.de>
To: Andi Kleen <ak@...e.de>
Cc: Grzegorz Chwesewicz <grzegorz.chwesewicz@...lan.com>,
Stefan Prechtel <stefan.prechtel@...glemail.com>,
linux-kernel@...r.kernel.org, mingo@...e.hu,
Len Brown <lenb@...nel.org>, john stultz <johnstul@...ibm.com>
Subject: Re: BUG lapic: Can't boot on battery (2.6.21-rc{1,2,3,4})
Stefan, Grzegorz
On Wed, 2007-03-21 at 12:14 +0100, Thomas Gleixner wrote:
> On Wed, 2007-03-21 at 11:37 +0100, Andi Kleen wrote:
> > > The BIOS/ACPI is broken and does only expose C1, which should not switch
> > > off LAPIC. The BIOS is switching into deeper C-States behind the kernels
> > > back somehow.
> >
> > Hmm, perhaps we can check AMD && (cstate >= 2 || has a battery) ?
> > Should be doable by looking up the battery object in ACPI
>
> Which makes us rely on another ACPI feature. What guarantees that the
> ACPI tables are correct for this one ?
Can you please apply the patch below and add "nolapic_timer" to the
kernel command line ?
Please provide also the output of
# dmidecode
on your laptops.
Thanks,
tglx
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index 5cff797..67f8d9f 100644
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -61,6 +61,8 @@ static int enable_local_apic __initdata = 0;
/* Local APIC timer verification ok */
static int local_apic_timer_verify_ok;
+/* Disable local APIC timer from the kernel commandline */
+static int local_apic_timer_disabled;
/*
* Debug level, exported for io_apic.c
@@ -340,6 +342,13 @@ void __init setup_boot_APIC_clock(void)
long delta, deltapm;
int pm_referenced = 0;
+ if (local_apic_timer_disabled) {
+ /* No broadcast on UP ! */
+ if (num_possible_cpus() > 1)
+ setup_APIC_timer();
+ return;
+ }}
+
apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
"calibrating APIC timer ...\n");
@@ -1179,6 +1188,13 @@ static int __init parse_nolapic(char *arg)
}
early_param("nolapic", parse_nolapic);
+static int __init parse_disable_lapic_timer(char *arg)
+{
+ local_apic_timer_disabled = 1;
+ return 0;
+}
+early_param("nolapic_timer", parse_disable_lapic_timer);
+
static int __init apic_set_verbosity(char *str)
{
if (strcmp("debug", str) == 0)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists