LXR linux/arch/h8300/kernel/timer/timer8.c

   1/*
   2 *  linux/arch/h8300/kernel/cpu/timer/timer8.c
   3 *
   4 *  Yoshinori Sato <ysato@users.sourcefoge.jp>
   5 *
   6 *  8bit Timer Handler
   7 *
   8 */
   9
  10#include <linux/errno.h>
  11#include <linux/sched.h>
  12#include <linux/kernel.h>
  13#include <linux/param.h>
  14#include <linux/string.h>
  15#include <linux/mm.h>
  16#include <linux/interrupt.h>
  17#include <linux/init.h>
  18#include <linux/profile.h>
  19
  20#include <asm/io.h>
  21#include <asm/irq.h>
  22#include <asm/timer.h>
  23#if defined(CONFIG_CPU_H8300H)
  24#include <asm/regs306x.h>
  25#endif
  26#if defined(CONFIG_CPU_H8S)
  27#include <asm/regs267x.h>
  28#endif
  29
  30/* 8bit timer x2 */
  31#define CMFA    6
  32
  33#if defined(CONFIG_H8300_TIMER8_CH0)
  34#define _8BASE  _8TCR0
  35#ifdef CONFIG_CPU_H8300H
  36#define _8IRQ   36
  37#endif
  38#ifdef CONFIG_CPU_H8S
  39#define _8IRQ   72
  40#endif
  41#elif defined(CONFIG_H8300_TIMER8_CH2)
  42#ifdef CONFIG_CPU_H8300H
  43#define _8BASE  _8TCR2
  44#define _8IRQ   40
  45#endif
  46#endif
  47
  48#ifndef _8BASE
  49#error Unknown timer channel.
  50#endif
  51
  52#define _8TCR   0
  53#define _8TCSR  2
  54#define TCORA   4
  55#define TCORB   6
  56#define _8TCNT  8
  57
  58#define CMIEA   0x40
  59#define CCLR_CMA 0x08
  60#define CKS2    0x04
  61
  62/*
  63 * timer_interrupt() needs to keep up the real-time clock,
  64 * as well as call the "xtime_update()" routine every clocktick
  65 */
  66
  67static irqreturn_t timer_interrupt(int irq, void *dev_id)
  68{
  69        h8300_timer_tick();
  70        ctrl_bclr(CMFA, _8BASE + _8TCSR);
  71        return IRQ_HANDLED;
  72}
  73
  74static struct irqaction timer8_irq = {
  75        .name           = "timer-8",
  76        .handler        = timer_interrupt,
  77        .flags          = IRQF_DISABLED | IRQF_TIMER,
  78};
  79
  80static const int __initdata divide_rate[] = {8, 64, 8192};
  81
  82void __init h8300_timer_setup(void)
  83{
  84        unsigned int div;
  85        unsigned int cnt;
  86
  87        calc_param(cnt, div, divide_rate, 0x10000);
  88        div++;
  89
  90        setup_irq(_8IRQ, &timer8_irq);
  91
  92#if defined(CONFIG_CPU_H8S)
  93        /* Timer module enable */
  94        ctrl_bclr(0, MSTPCRL)
  95#endif
  96
  97        /* initialize timer */
  98        ctrl_outw(cnt, _8BASE + TCORA);
  99        ctrl_outw(0x0000, _8BASE + _8TCSR);
 100        ctrl_outw((CMIEA|CCLR_CMA|CKS2) << 8 | div,
 101                  _8BASE + _8TCR);
 102}
 103