[PATCH] x86_64: Force broadcast timer on AMD systems with C3 too.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/acpi/processor_idle.c

@@ -876,14 +876,11 @@ static int acpi_processor_power_verify(struct acpi_processor *pr)
 {
 	unsigned int i;
 	unsigned int working = 0;
-
-#ifdef ARCH_APICTIMER_STOPS_ON_C3
-	struct cpuinfo_x86 *c = cpu_data + pr->id;
+	int timer_broadcast = 0;
 	cpumask_t mask = cpumask_of_cpu(pr->id);
 
-	if (c->x86_vendor == X86_VENDOR_INTEL) {
+#ifdef ARCH_APICTIMER_STOPS_ON_C3
 	on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1);
-	}
 #endif
 
 	for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) {
@@ -896,15 +893,20 @@ static int acpi_processor_power_verify(struct acpi_processor *pr)
 
 		case ACPI_STATE_C2:
 			acpi_processor_power_verify_c2(cx);
+#ifdef ARCH_APICTIMER_STOPS_ON_C3
+			/* Some AMD systems fake C3 as C2, but still
+			   have timer troubles */
+			if (cx->valid && 
+				boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
+				timer_broadcast++;
+#endif
 			break;
 
 		case ACPI_STATE_C3:
 			acpi_processor_power_verify_c3(pr, cx);
 #ifdef ARCH_APICTIMER_STOPS_ON_C3
-			if (cx->valid && c->x86_vendor == X86_VENDOR_INTEL) {
-				on_each_cpu(switch_APIC_timer_to_ipi,
-						&mask, 1, 1);
-			}
+			if (cx->valid)
+				timer_broadcast++;
 #endif
 			break;
 		}
@@ -913,6 +915,9 @@ static int acpi_processor_power_verify(struct acpi_processor *pr)
 			working++;
 	}
 
+	if (timer_broadcast)
+		on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1);
+
 	return (working);
 }