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-rw-r--r--arch/i386/kernel/apic.c48
1 files changed, 42 insertions, 6 deletions
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index 5ab59c12335..90faae5c5d3 100644
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -14,7 +14,6 @@
* Mikael Pettersson : PM converted to driver model.
*/
-#include <linux/config.h>
#include <linux/init.h>
#include <linux/mm.h>
@@ -36,6 +35,7 @@
#include <asm/arch_hooks.h>
#include <asm/hpet.h>
#include <asm/i8253.h>
+#include <asm/nmi.h>
#include <mach_apic.h>
#include <mach_apicdef.h>
@@ -52,7 +52,18 @@ static cpumask_t timer_bcast_ipi;
/*
* Knob to control our willingness to enable the local APIC.
*/
-int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
+static int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
+
+static inline void lapic_disable(void)
+{
+ enable_local_apic = -1;
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+}
+
+static inline void lapic_enable(void)
+{
+ enable_local_apic = 1;
+}
/*
* Debug level
@@ -156,7 +167,7 @@ void clear_local_APIC(void)
maxlvt = get_maxlvt();
/*
- * Masking an LVT entry on a P6 can trigger a local APIC error
+ * Masking an LVT entry can trigger a local APIC error
* if the vector is zero. Mask LVTERR first to prevent this.
*/
if (maxlvt >= 3) {
@@ -586,8 +597,7 @@ void __devinit setup_local_APIC(void)
printk("No ESR for 82489DX.\n");
}
- if (nmi_watchdog == NMI_LOCAL_APIC)
- setup_apic_nmi_watchdog();
+ setup_apic_nmi_watchdog(NULL);
apic_pm_activate();
}
@@ -1117,7 +1127,18 @@ void disable_APIC_timer(void)
unsigned long v;
v = apic_read(APIC_LVTT);
- apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
+ /*
+ * When an illegal vector value (0-15) is written to an LVT
+ * entry and delivery mode is Fixed, the APIC may signal an
+ * illegal vector error, with out regard to whether the mask
+ * bit is set or whether an interrupt is actually seen on input.
+ *
+ * Boot sequence might call this function when the LVTT has
+ * '0' vector value. So make sure vector field is set to
+ * valid value.
+ */
+ v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
+ apic_write_around(APIC_LVTT, v);
}
}
@@ -1362,3 +1383,18 @@ int __init APIC_init_uniprocessor (void)
return 0;
}
+
+static int __init parse_lapic(char *arg)
+{
+ lapic_enable();
+ return 0;
+}
+early_param("lapic", parse_lapic);
+
+static int __init parse_nolapic(char *arg)
+{
+ lapic_disable();
+ return 0;
+}
+early_param("nolapic", parse_nolapic);
+