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ACPI: move timer broadcast before busmaster disable

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The timer broadcast code might access HPET, which should not be
accessed after the busmaster disable.

In acpi_idle_enter_simple() this change also prevents, that we modify
the busmaster state without going actually idle. This might leave the
ACPI bm state in a stale state, when we leave the function early in
the need_resched() check.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
This commit is contained in:
Thomas Gleixner 2007-12-07 19:16:17 +01:00 committed by Ingo Molnar
parent 167b1de3ee
commit e17bcb43a2
1 changed files with 14 additions and 5 deletions
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19
drivers/acpi/processor_idle.c
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@ -530,6 +530,11 @@ static void acpi_processor_idle(void)
break;
case ACPI_STATE_C3:
/*
* Must be done before busmaster disable as we might
* need to access HPET !
*/
acpi_state_timer_broadcast(pr, cx, 1);
/*
* disable bus master
* bm_check implies we need ARB_DIS
@ -557,7 +562,6 @@ static void acpi_processor_idle(void)
/* Get start time (ticks) */
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Invoke C3 */
acpi_state_timer_broadcast(pr, cx, 1);
/* Tell the scheduler that we are going deep-idle: */
sched_clock_idle_sleep_event();
acpi_cstate_enter(cx);
@ -1401,9 +1405,6 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
if (acpi_idle_suspend)
return(acpi_idle_enter_c1(dev, state));
if (pr->flags.bm_check)
acpi_idle_update_bm_rld(pr, cx);
local_irq_disable();
current_thread_info()->status &= ~TS_POLLING;
/*
@ -1418,13 +1419,21 @@ static int acpi_idle_enter_simple(struct cpuidle_device *dev,
return 0;
}
/*
* Must be done before busmaster disable as we might need to
* access HPET !
*/
acpi_state_timer_broadcast(pr, cx, 1);
if (pr->flags.bm_check)
acpi_idle_update_bm_rld(pr, cx);
if (cx->type == ACPI_STATE_C3)
ACPI_FLUSH_CPU_CACHE();
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Tell the scheduler that we are going deep-idle: */
sched_clock_idle_sleep_event();
acpi_state_timer_broadcast(pr, cx, 1);
acpi_idle_do_entry(cx);
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);