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
  67 static 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
  74 static struct irqaction timer8_irq = {
  75         .name           = "timer-8",
  76         .handler        = timer_interrupt,
  77         .flags          = IRQF_DISABLED | IRQF_TIMER,
  78 };
  79
  80 static const int __initdata divide_rate[] = {8, 64, 8192};
  81
  82 void __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 }