From: Udo A. Steinberg <us15@xxxxxxxxxxxxxxxxxxxx>
The chipset doc for IHC4 tells us:
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@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Len Brown <lenb@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/acpi/processor_idle.c | 7 ++++++-
1 files changed, 6 insertions(+), 1 deletion(-)
diff -puN drivers/acpi/processor_idle.c~acpi-move-timer-broadcast-and-pmtimer-access-before-c3-arbiter-shutdown drivers/acpi/processor_idle.c
--- a/drivers/acpi/processor_idle.c~acpi-move-timer-broadcast-and-pmtimer-access-before-c3-arbiter-shutdown
+++ a/drivers/acpi/processor_idle.c
@@ -1009,6 +1009,12 @@ static int acpi_idle_enter_c3(struct cpu
return 0;
}
+ /*
+ * Must be done before busmaster disable as we might need to
+ * access HPET!
+ */
+ acpi_state_timer_broadcast(pr, cx, 1);
+
/* disable bus master */
if (pr->flags.bm_check) {
spin_lock(&c3_lock);
@@ -1028,7 +1034,6 @@ static int acpi_idle_enter_c3(struct cpu
/* Get start time (ticks) */
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
- acpi_state_timer_broadcast(pr, cx, 1);
acpi_idle_do_entry(cx);
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
_
-
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