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@@ -0,0 +1,94 @@
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+/*
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+ * arch/arm/plat-iop/time.c
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+ *
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+ * Timer code for IOP32x and IOP33x based systems
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+ *
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+ * Author: Deepak Saxena <dsaxena@mvista.com>
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+ *
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+ * Copyright 2002-2003 MontaVista Software Inc.
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+ *
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+ * This program is free software; you can redistribute it and/or modify it
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+ * under the terms of the GNU General Public License as published by the
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+ * Free Software Foundation; either version 2 of the License, or (at your
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+ * option) any later version.
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+ */
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+
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+#include <linux/kernel.h>
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+#include <linux/interrupt.h>
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+#include <linux/time.h>
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+#include <linux/init.h>
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+#include <linux/timex.h>
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+#include <asm/hardware.h>
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+#include <asm/io.h>
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+#include <asm/irq.h>
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+#include <asm/uaccess.h>
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+#include <asm/mach/irq.h>
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+#include <asm/mach/time.h>
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+
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+#ifdef CONFIG_ARCH_IOP32X
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+#define IRQ_IOP3XX_TIMER0 IRQ_IOP321_TIMER0
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+#else
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+#ifdef CONFIG_ARCH_IOP33X
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+#define IRQ_IOP3XX_TIMER0 IRQ_IOP331_TIMER0
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+#endif
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+#endif
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+
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+static unsigned long ticks_per_jiffy;
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+static unsigned long ticks_per_usec;
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+static unsigned long next_jiffy_time;
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+
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+unsigned long iop3xx_gettimeoffset(void)
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+{
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+ unsigned long offset;
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+
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+ offset = next_jiffy_time - *IOP3XX_TU_TCR1;
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+
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+ return offset / ticks_per_usec;
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+}
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+
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+static irqreturn_t
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+iop3xx_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
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+{
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+ write_seqlock(&xtime_lock);
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+
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+ asm volatile("mcr p6, 0, %0, c6, c1, 0" : : "r" (1));
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+
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+ while ((signed long)(next_jiffy_time - *IOP3XX_TU_TCR1)
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+ >= ticks_per_jiffy) {
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+ timer_tick(regs);
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+ next_jiffy_time -= ticks_per_jiffy;
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+ }
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+
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+ write_sequnlock(&xtime_lock);
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+
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+ return IRQ_HANDLED;
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+}
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+
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+static struct irqaction iop3xx_timer_irq = {
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+ .name = "IOP3XX Timer Tick",
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+ .handler = iop3xx_timer_interrupt,
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+ .flags = IRQF_DISABLED | IRQF_TIMER,
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+};
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+
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+void __init iop3xx_init_time(unsigned long tick_rate)
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+{
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+ u32 timer_ctl;
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+
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+ ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
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+ ticks_per_usec = tick_rate / 1000000;
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+ next_jiffy_time = 0xffffffff;
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+
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+ timer_ctl = IOP3XX_TMR_EN | IOP3XX_TMR_PRIVILEGED |
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+ IOP3XX_TMR_RELOAD | IOP3XX_TMR_RATIO_1_1;
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+
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+ /*
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+ * We use timer 0 for our timer interrupt, and timer 1 as
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+ * monotonic counter for tracking missed jiffies.
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+ */
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+ asm volatile("mcr p6, 0, %0, c4, c1, 0" : : "r" (ticks_per_jiffy - 1));
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+ asm volatile("mcr p6, 0, %0, c0, c1, 0" : : "r" (timer_ctl));
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+ asm volatile("mcr p6, 0, %0, c5, c1, 0" : : "r" (0xffffffff));
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+ asm volatile("mcr p6, 0, %0, c1, c1, 0" : : "r" (timer_ctl));
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+
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+ setup_irq(IRQ_IOP3XX_TIMER0, &iop3xx_timer_irq);
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+}
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