1/*
2 *  linux/arch/h8300/kernel/timer/timer16.c
3 *
4 *  Yoshinori Sato <ysato@users.sourcefoge.jp>
5 *
6 *  16bit 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/timex.h>
19
20#include <asm/segment.h>
21#include <asm/io.h>
22#include <asm/irq.h>
23#include <asm/regs306x.h>
24
25/* 16bit timer */
26#if CONFIG_H8300_TIMER16_CH == 0
27#define _16BASE	0xffff78
28#define _16IRQ	24
29#elif CONFIG_H8300_TIMER16_CH == 1
30#define _16BASE	0xffff80
31#define _16IRQ	28
32#elif CONFIG_H8300_TIMER16_CH == 2
33#define _16BASE	0xffff88
34#define _16IRQ	32
35#else
36#error Unknown timer channel.
37#endif
38
39#define TCR	0
40#define TIOR	1
41#define TCNT	2
42#define GRA	4
43#define GRB	6
44
45#define H8300_TIMER_FREQ CONFIG_CPU_CLOCK*10000 /* Timer input freq. */
46
47static irqreturn_t timer_interrupt(int irq, void *dev_id)
48{
49	h8300_timer_tick();
50	ctrl_bclr(CONFIG_H8300_TIMER16_CH, TISRA);
51	return IRQ_HANDLED;
52}
53
54static struct irqaction timer16_irq = {
55	.name		= "timer-16",
56	.handler	= timer_interrupt,
57	.flags		= IRQF_DISABLED | IRQF_TIMER,
58};
59
60static const int __initdata divide_rate[] = {1, 2, 4, 8};
61
62void __init h8300_timer_setup(void)
63{
64	unsigned int div;
65	unsigned int cnt;
66
67	calc_param(cnt, div, divide_rate, 0x10000);
68
69	setup_irq(_16IRQ, &timer16_irq);
70
71	/* initialize timer */
72	ctrl_outb(0, TSTR);
73	ctrl_outb(CCLR0 | div, _16BASE + TCR);
74	ctrl_outw(cnt, _16BASE + GRA);
75	ctrl_bset(4 + CONFIG_H8300_TIMER16_CH, TISRA);
76	ctrl_bset(CONFIG_H8300_TIMER16_CH, TSTR);
77}
78