lkml.org 
[lkml]   [2007]   [Jun]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[PATCH] ACPI: Move timer broadcast and pmtimer access before C3 arbiter shutdown
From
Date
From: Udo A. Steinberg <us15@os.inf.tu-dresden.de>

The chip set doc for IHC4 says:

1.In general, software should not attempt any non-posted accesses during
arbiter disable except to the ICH4's power management registers. This
implies that interrupt handlers for any unmasked hardware interrupts and
SMI/NMI should check ARB_DIS status before reading from ICH devices.

So it's not a good idea to access ICH devices after arbiter shut down.

Signed-off-by: Udo A. Steinberg <us15@os.inf.tu-dresden.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
drivers/acpi/processor_idle.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
Index: linux-2.6.22-rc4/drivers/acpi/processor_idle.c
===================================================================
--- linux-2.6.22-rc4.orig/drivers/acpi/processor_idle.c 2007-06-06 11:47:21.000000000 +0200
+++ linux-2.6.22-rc4/drivers/acpi/processor_idle.c 2007-06-06 11:48:21.000000000 +0200
@@ -488,6 +488,11 @@ static void acpi_processor_idle(void)

case ACPI_STATE_C3:

+ /* Get start time (ticks) */
+ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ /* Handle timer broadcast before bus arbiter shutdown ! */
+ acpi_state_timer_broadcast(pr, cx, 1);
+
if (pr->flags.bm_check) {
if (atomic_inc_return(&c3_cpu_count) ==
num_online_cpus()) {
@@ -502,10 +507,7 @@ static void acpi_processor_idle(void)
ACPI_FLUSH_CPU_CACHE();
}

- /* Get start time (ticks) */
- t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Invoke C3 */
- acpi_state_timer_broadcast(pr, cx, 1);
acpi_cstate_enter(cx);
/* Get end time (ticks) */
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-06-06 11:41    [from the cache]
©2003-2011 Jasper Spaans