[patch 21/60] cpuidle: make AMC C1E work in processor_idle

From: Greg KH
Date: Tue Jun 09 2009 - 23:39:22 EST


-stable review patch. If anyone has any objections, please let us know.

------------------
From: Shaohua Li <shaohua.li@xxxxxxxxx>

commit 87ad57bacb25c3f24c54f142ef445f68277705f0 upstream

When AMD C1E is enabled, local APIC timer will stop even in C1. This patch uses
broadcast ipi to replace local APIC timer in C1.

http://bugzilla.kernel.org/show_bug.cgi?id=13233

[ impact: avoid boot hang in AMD CPU with C1E enabled ]

Tested-by: Dmitry Lyzhyn <thisistempbox@xxxxxxxxx>
Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx>
Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/acpi/processor_idle.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -303,6 +303,9 @@ static void acpi_timer_check_state(int s
struct acpi_processor_power *pwr = &pr->power;
u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2;

+ if (boot_cpu_has(X86_FEATURE_AMDC1E))
+ type = ACPI_STATE_C1;
+
/*
* Check, if one of the previous states already marked the lapic
* unstable
@@ -1154,6 +1157,7 @@ static int acpi_processor_power_verify(s
switch (cx->type) {
case ACPI_STATE_C1:
cx->valid = 1;
+ acpi_timer_check_state(i, pr, cx);
break;

case ACPI_STATE_C2:
@@ -1476,12 +1480,14 @@ static int acpi_idle_enter_c1(struct cpu
if (pr->flags.bm_check)
acpi_idle_update_bm_rld(pr, cx);

+ acpi_state_timer_broadcast(pr, cx, 1);
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
acpi_idle_do_entry(cx);
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);

local_irq_enable();
cx->usage++;
+ acpi_state_timer_broadcast(pr, cx, 0);

return ticks_elapsed_in_us(t1, t2);
}


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