1 files changed, 134 insertions, 0 deletions
diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c
new file mode 100644
index 000000000..8d0170969
--- /dev/null
+++ b/arch/mips/kernel/time.c
@@ -0,0 +1,134 @@
+/*
+ * 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/cpu-type.h>
+#include <asm/div64.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();
+
+	/*
+	 * The use of the R4k timer as a clock event takes precedence;
+	 * if reading the Count register might interfere with the timer
+	 * interrupt, then we don't use the timer as a clock source.
+	 * We may still use the timer as a clock source though if the
+	 * timer interrupt isn't reliable; the interference doesn't
+	 * matter then, because we don't use the interrupt.
+	 */
+	if (mips_clockevent_init() != 0 || !cpu_has_mfc0_count_bug())
+		init_mips_clocksource();
+}