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diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c
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+/*
+ * Copyright 2001 MontaVista Software Inc.
+ * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
+ * Copyright (c) 2003, 2004 Maciej W. Rozycki
+ *
+ * Common time service routines for MIPS machines.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+#include <linux/bug.h>
+#include <linux/clockchips.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/param.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/smp.h>
+#include <linux/spinlock.h>
+#include <linux/export.h>
+
+#include <asm/cpu-features.h>
+#include <asm/div64.h>
+#include <asm/smtc_ipi.h>
+#include <asm/time.h>
+
+/*
+ * forward reference
+ */
+DEFINE_SPINLOCK(rtc_lock);
+EXPORT_SYMBOL(rtc_lock);
+
+int __weak rtc_mips_set_time(unsigned long sec)
+{
+ return 0;
+}
+
+int __weak rtc_mips_set_mmss(unsigned long nowtime)
+{
+ return rtc_mips_set_time(nowtime);
+}
+
+int update_persistent_clock(struct timespec now)
+{
+ return rtc_mips_set_mmss(now.tv_sec);
+}
+
+static int null_perf_irq(void)
+{
+ return 0;
+}
+
+int (*perf_irq)(void) = null_perf_irq;
+
+EXPORT_SYMBOL(perf_irq);
+
+/*
+ * time_init() - it does the following things.
+ *
+ * 1) plat_time_init() -
+ * a) (optional) set up RTC routines,
+ * b) (optional) calibrate and set the mips_hpt_frequency
+ * (only needed if you intended to use cpu counter as timer interrupt
+ * source)
+ * 2) calculate a couple of cached variables for later usage
+ */
+
+unsigned int mips_hpt_frequency;
+
+/*
+ * This function exists in order to cause an error due to a duplicate
+ * definition if platform code should have its own implementation. The hook
+ * to use instead is plat_time_init. plat_time_init does not receive the
+ * irqaction pointer argument anymore. This is because any function which
+ * initializes an interrupt timer now takes care of its own request_irq rsp.
+ * setup_irq calls and each clock_event_device should use its own
+ * struct irqrequest.
+ */
+void __init plat_timer_setup(void)
+{
+ BUG();
+}
+
+static __init int cpu_has_mfc0_count_bug(void)
+{
+ switch (current_cpu_type()) {
+ case CPU_R4000PC:
+ case CPU_R4000SC:
+ case CPU_R4000MC:
+ /*
+ * V3.0 is documented as suffering from the mfc0 from count bug.
+ * Afaik this is the last version of the R4000. Later versions
+ * were marketed as R4400.
+ */
+ return 1;
+
+ case CPU_R4400PC:
+ case CPU_R4400SC:
+ case CPU_R4400MC:
+ /*
+ * The published errata for the R4400 up to 3.0 say the CPU
+ * has the mfc0 from count bug.
+ */
+ if ((current_cpu_data.processor_id & 0xff) <= 0x30)
+ return 1;
+
+ /*
+ * we assume newer revisions are ok
+ */
+ return 0;
+ }
+
+ return 0;
+}
+
+void __init time_init(void)
+{
+ plat_time_init();
+
+ if (!mips_clockevent_init() || !cpu_has_mfc0_count_bug())
+ init_mips_clocksource();
+}