Messages in this thread Patch in this message | | | Date | Mon, 11 Jun 2007 18:07:35 -0700 | From | Chris Wright <> | Subject | Re: [stable] [PATCH] ACPI: Move timer broadcast and pmtimer access before C3 arbiter shutdown |
| |
* Andrew Morton (akpm@linux-foundation.org) wrote: > hm, this needs a bit of help to get it to work against Len's current tree.
Here's some help, compile tested only. Udo/Thomas, was this found to be root cause of a real bug? I didn't want this to get lost if it's still meant to be relevant for -stable.
thanks, -chris --
Subject: ACPI: Move timer broadcast and pmtimer access before C3 arbiter shutdown
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> [chrisw: rebase against Len's changes in -mm] Signed-off-by: Chris Wright <chrisw@sous-sol.org>
---
drivers/acpi/processor_idle.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 2c6a3cb..15db3e8 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -978,6 +978,11 @@ static int acpi_idle_enter_c3(struct cpuidle_device *dev, return 0; } + /* 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); + /* disable bus master */ if (pr->flags.bm_check) { spin_lock(&c3_lock); @@ -995,10 +1000,6 @@ static int acpi_idle_enter_c3(struct cpuidle_device *dev, ACPI_FLUSH_CPU_CACHE(); } - /* 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); if (pr->flags.bm_check) { - 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/
| |