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}