arch/arm/mach-h720x/cpu-h7201.c

   1 /*
   2  * linux/arch/arm/mach-h720x/cpu-h7201.c
   3  *
   4  * Copyright (C) 2003 Thomas Gleixner <tglx@linutronix.de>
   5  *               2003 Robert Schwebel <r.schwebel@pengutronix.de>
   6  *               2004 Sascha Hauer    <s.hauer@pengutronix.de>
   7  *
   8  * processor specific stuff for the Hynix h7201
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  *
  14  */
  15
  16 #include <linux/init.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/module.h>
  19 #include <asm/types.h>
  20 #include <asm/hardware.h>
  21 #include <asm/irq.h>
  22 #include <asm/arch/irqs.h>
  23 #include <asm/mach/irq.h>
  24 #include <asm/mach/time.h>
  25 #include "common.h"
  26 /*
  27  * Timer interrupt handler
  28  */
  29 static irqreturn_t
  30 h7201_timer_interrupt(int irq, void *dev_id)
  31 {
  32         write_seqlock(&xtime_lock);
  33
  34         CPU_REG (TIMER_VIRT, TIMER_TOPSTAT);
  35         timer_tick();
  36
  37         write_sequnlock(&xtime_lock);
  38
  39         return IRQ_HANDLED;
  40 }
  41
  42 static struct irqaction h7201_timer_irq = {
  43         .name           = "h7201 Timer Tick",
  44         .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
  45         .handler        = h7201_timer_interrupt,
  46 };
  47
  48 /*
  49  * Setup TIMER0 as system timer
  50  */
  51 void __init h7201_init_time(void)
  52 {
  53         CPU_REG (TIMER_VIRT, TM0_PERIOD) = LATCH;
  54         CPU_REG (TIMER_VIRT, TM0_CTRL) = TM_RESET;
  55         CPU_REG (TIMER_VIRT, TM0_CTRL) = TM_REPEAT | TM_START;
  56         CPU_REG (TIMER_VIRT, TIMER_TOPCTRL) = ENABLE_TM0_INTR | TIMER_ENABLE_BIT;
  57
  58         setup_irq(IRQ_TIMER0, &h7201_timer_irq);
  59 }
  60
  61 struct sys_timer h7201_timer = {
  62         .init           = h7201_init_time,
  63         .offset         = h720x_gettimeoffset,
  64 };