1 files changed, 236 insertions, 0 deletions

diff --git a/arch/i386/kernel/time_32.c b/arch/i386/kernel/time_32.c
new file mode 100644
index 000000000000..19a6c678d02e
--- /dev/null
+++ b/arch/i386/kernel/time_32.c
@@ -0,0 +1,236 @@
+/*
+ *  linux/arch/i386/kernel/time.c
+ *
+ *  Copyright (C) 1991, 1992, 1995  Linus Torvalds
+ *
+ * This file contains the PC-specific time handling details:
+ * reading the RTC at bootup, etc..
+ * 1994-07-02    Alan Modra
+ *      fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime
+ * 1995-03-26    Markus Kuhn
+ *      fixed 500 ms bug at call to set_rtc_mmss, fixed DS12887
+ *      precision CMOS clock update
+ * 1996-05-03    Ingo Molnar
+ *      fixed time warps in do_[slow|fast]_gettimeoffset()
+ * 1997-09-10   Updated NTP code according to technical memorandum Jan '96
+ *              "A Kernel Model for Precision Timekeeping" by Dave Mills
+ * 1998-09-05    (Various)
+ *      More robust do_fast_gettimeoffset() algorithm implemented
+ *      (works with APM, Cyrix 6x86MX and Centaur C6),
+ *      monotonic gettimeofday() with fast_get_timeoffset(),
+ *      drift-proof precision TSC calibration on boot
+ *      (C. Scott Ananian <cananian@alumni.princeton.edu>, Andrew D.
+ *      Balsa <andrebalsa@altern.org>, Philip Gladstone <philip@raptor.com>;
+ *      ported from 2.0.35 Jumbo-9 by Michael Krause <m.krause@tu-harburg.de>).
+ * 1998-12-16    Andrea Arcangeli
+ *      Fixed Jumbo-9 code in 2.1.131: do_gettimeofday was missing 1 jiffy
+ *      because was not accounting lost_ticks.
+ * 1998-12-24 Copyright (C) 1998  Andrea Arcangeli
+ *      Fixed a xtime SMP race (we need the xtime_lock rw spinlock to
+ *      serialize accesses to xtime/lost_ticks).
+ */
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/module.h>
+#include <linux/sysdev.h>
+#include <linux/bcd.h>
+#include <linux/efi.h>
+#include <linux/mca.h>
+
+#include <asm/io.h>
+#include <asm/smp.h>
+#include <asm/irq.h>
+#include <asm/msr.h>
+#include <asm/delay.h>
+#include <asm/mpspec.h>
+#include <asm/uaccess.h>
+#include <asm/processor.h>
+#include <asm/timer.h>
+#include <asm/time.h>
+
+#include "mach_time.h"
+
+#include <linux/timex.h>
+
+#include <asm/hpet.h>
+
+#include <asm/arch_hooks.h>
+
+#include "io_ports.h"
+
+#include <asm/i8259.h>
+
+#include "do_timer.h"
+
+unsigned int cpu_khz;   /* Detected as we calibrate the TSC */
+EXPORT_SYMBOL(cpu_khz);
+
+DEFINE_SPINLOCK(rtc_lock);
+EXPORT_SYMBOL(rtc_lock);
+
+/*
+ * This is a special lock that is owned by the CPU and holds the index
+ * register we are working with.  It is required for NMI access to the
+ * CMOS/RTC registers.  See include/asm-i386/mc146818rtc.h for details.
+ */
+volatile unsigned long cmos_lock = 0;
+EXPORT_SYMBOL(cmos_lock);
+
+/* Routines for accessing the CMOS RAM/RTC. */
+unsigned char rtc_cmos_read(unsigned char addr)
+{
+        unsigned char val;
+        lock_cmos_prefix(addr);
+        outb_p(addr, RTC_PORT(0));
+        val = inb_p(RTC_PORT(1));
+        lock_cmos_suffix(addr);
+        return val;
+}
+EXPORT_SYMBOL(rtc_cmos_read);
+
+void rtc_cmos_write(unsigned char val, unsigned char addr)
+{
+        lock_cmos_prefix(addr);
+        outb_p(addr, RTC_PORT(0));
+        outb_p(val, RTC_PORT(1));
+        lock_cmos_suffix(addr);
+}
+EXPORT_SYMBOL(rtc_cmos_write);
+
+static int set_rtc_mmss(unsigned long nowtime)
+{
+        int retval;
+        unsigned long flags;
+
+        /* gets recalled with irq locally disabled */
+        /* XXX - does irqsave resolve this? -johnstul */
+        spin_lock_irqsave(&rtc_lock, flags);
+        retval = set_wallclock(nowtime);
+        spin_unlock_irqrestore(&rtc_lock, flags);
+
+        return retval;
+}
+
+
+int timer_ack;
+
+unsigned long profile_pc(struct pt_regs *regs)
+{
+        unsigned long pc = instruction_pointer(regs);
+
+#ifdef CONFIG_SMP
+        if (!v8086_mode(regs) && SEGMENT_IS_KERNEL_CODE(regs->xcs) &&
+            in_lock_functions(pc)) {
+#ifdef CONFIG_FRAME_POINTER
+                return *(unsigned long *)(regs->ebp + 4);
+#else
+                unsigned long *sp = (unsigned long *)&regs->esp;
+
+                /* Return address is either directly at stack pointer
+                   or above a saved eflags. 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
+        }
+#endif
+        return pc;
+}
+EXPORT_SYMBOL(profile_pc);
+
+/*
+ * This is the same as the above, except we _also_ save the current
+ * Time Stamp Counter value at the time of the timer interrupt, so that
+ * we later on can estimate the time of day more exactly.
+ */
+irqreturn_t timer_interrupt(int irq, void *dev_id)
+{
+#ifdef CONFIG_X86_IO_APIC
+        if (timer_ack) {
+                /*
+                 * Subtle, when I/O APICs are used we have to ack timer IRQ
+                 * manually to reset the IRR bit for do_slow_gettimeoffset().
+                 * This will also 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);
+        }
+#endif
+
+        do_timer_interrupt_hook();
+
+        if (MCA_bus) {
+                /* The PS/2 uses level-triggered interrupts.  You can't
+                turn them off, nor would you want to (any attempt to
+                enable edge-triggered interrupts usually gets intercepted by a
+                special hardware circuit).  Hence we have to acknowledge
+                the timer interrupt.  Through some incredibly stupid
+                design idea, the reset for IRQ 0 is done by setting the
+                high bit of the PPI port B (0x61).  Note that some PS/2s,
+                notably the 55SX, work fine if this is removed.  */
+
+                u8 irq_v = inb_p( 0x61 );       /* read the current state */
+                outb_p( irq_v|0x80, 0x61 );     /* reset the IRQ */
+        }
+
+        return IRQ_HANDLED;
+}
+
+/* not static: needed by APM */
+unsigned long read_persistent_clock(void)
+{
+        unsigned long retval;
+        unsigned long flags;
+
+        spin_lock_irqsave(&rtc_lock, flags);
+
+        retval = get_wallclock();
+
+        spin_unlock_irqrestore(&rtc_lock, flags);
+
+        return retval;
+}
+
+int update_persistent_clock(struct timespec now)
+{
+        return set_rtc_mmss(now.tv_sec);
+}
+
+extern void (*late_time_init)(void);
+/* Duplicate of time_init() below, with hpet_enable part added */
+void __init hpet_time_init(void)
+{
+        if (!hpet_enable())
+                setup_pit_timer();
+        time_init_hook();
+}
+
+/*
+ * This is called directly from init code; we must delay timer setup in the
+ * HPET case as we can't make the decision to turn on HPET this early in the
+ * boot process.
+ *
+ * The chosen time_init function will usually be hpet_time_init, above, but
+ * in the case of virtual hardware, an alternative function may be substituted.
+ */
+void __init time_init(void)
+{
+        tsc_init();
+        late_time_init = choose_time_init();
+}