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-rw-r--r--arch/x86/kernel/time.c121
1 files changed, 121 insertions, 0 deletions
diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c
new file mode 100644
index 00000000000..fda0c34da75
--- /dev/null
+++ b/arch/x86/kernel/time.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 1991,1992,1995 Linus Torvalds
+ * Copyright (c) 1994 Alan Modra
+ * Copyright (c) 1995 Markus Kuhn
+ * Copyright (c) 1996 Ingo Molnar
+ * Copyright (c) 1998 Andrea Arcangeli
+ * Copyright (c) 2002,2006 Vojtech Pavlik
+ * Copyright (c) 2003 Andi Kleen
+ *
+ */
+
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/mca.h>
+
+#include <asm/vsyscall.h>
+#include <asm/x86_init.h>
+#include <asm/i8259.h>
+#include <asm/i8253.h>
+#include <asm/timer.h>
+#include <asm/hpet.h>
+#include <asm/time.h>
+
+#if defined(CONFIG_X86_32) && defined(CONFIG_X86_IO_APIC)
+int timer_ack;
+#endif
+
+#ifdef CONFIG_X86_64
+volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES;
+#endif
+
+unsigned long profile_pc(struct pt_regs *regs)
+{
+ unsigned long pc = instruction_pointer(regs);
+
+ if (!user_mode_vm(regs) && in_lock_functions(pc)) {
+#ifdef CONFIG_FRAME_POINTER
+ return *(unsigned long *)(regs->bp + sizeof(long));
+#else
+ unsigned long *sp = (unsigned long *)regs->sp;
+ /*
+ * Return address is either directly at stack pointer
+ * or above a saved flags. Eflags has bits 22-31 zero,
+ * kernel addresses don't.
+ */
+ if (sp[0] >> 22)
+ return sp[0];
+ if (sp[1] >> 22)
+ return sp[1];
+#endif
+ }
+ return pc;
+}
+EXPORT_SYMBOL(profile_pc);
+
+/*
+ * Default timer interrupt handler for PIT/HPET
+ */
+static irqreturn_t timer_interrupt(int irq, void *dev_id)
+{
+ /* Keep nmi watchdog up to date */
+ inc_irq_stat(irq0_irqs);
+
+ /* Optimized out for !IO_APIC and x86_64 */
+ if (timer_ack) {
+ /*
+ * Subtle, when I/O APICs are used we have to ack timer IRQ
+ * manually to deassert NMI lines for the watchdog if run
+ * on an 82489DX-based system.
+ */
+ spin_lock(&i8259A_lock);
+ outb(0x0c, PIC_MASTER_OCW3);
+ /* Ack the IRQ; AEOI will end it automatically. */
+ inb(PIC_MASTER_POLL);
+ spin_unlock(&i8259A_lock);
+ }
+
+ global_clock_event->event_handler(global_clock_event);
+
+ /* MCA bus quirk: Acknowledge irq0 by setting bit 7 in port 0x61 */
+ if (MCA_bus)
+ outb_p(inb_p(0x61)| 0x80, 0x61);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction irq0 = {
+ .handler = timer_interrupt,
+ .flags = IRQF_DISABLED | IRQF_NOBALANCING | IRQF_IRQPOLL | IRQF_TIMER,
+ .name = "timer"
+};
+
+void __init setup_default_timer_irq(void)
+{
+ irq0.mask = cpumask_of_cpu(0);
+ setup_irq(0, &irq0);
+}
+
+/* Default timer init function */
+void __init hpet_time_init(void)
+{
+ if (!hpet_enable())
+ setup_pit_timer();
+ setup_default_timer_irq();
+}
+
+static void x86_late_time_init(void)
+{
+ x86_init.timers.timer_init();
+}
+
+/*
+ * Initialize TSC and delay the periodic timer init to
+ * late x86_late_time_init() so ioremap works.
+ */
+void __init time_init(void)
+{
+ tsc_init();
+ late_time_init = x86_late_time_init;
+}