lib_m68k/time.c

   1 /*
   2  * (C) Copyright 2003 Josef Baumgartner <josef.baumgartner@telex.de>
   3  *
   4  * (C) Copyright 2000
   5  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   6  *
   7  * See file CREDITS for list of people who contributed to this
   8  * project.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License as
  12  * published by the Free Software Foundation; either version 2 of
  13  * the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  23  * MA 02111-1307 USA
  24  */
  25
  26 #include <common.h>
  27
  28 #include <asm/mcftimer.h>
  29
  30 #ifdef  CONFIG_M5272
  31 #include <asm/m5272.h>
  32 #include <asm/immap_5272.h>
  33 #endif
  34
  35 #ifdef  CONFIG_M5282
  36 #include <asm/m5282.h>
  37 #endif
  38
  39
  40 static ulong timestamp;
  41 #ifdef  CONFIG_M5282
  42 static unsigned short lastinc;
  43 #endif
  44
  45
  46 #if defined(CONFIG_M5272)
  47 /*
  48  * We use timer 3 which is running with a period of 1 us
  49  */
  50 void udelay(unsigned long usec)
  51 {
  52         volatile timer_t *timerp = (timer_t *) (CFG_MBAR + MCFTIMER_BASE3);
  53         uint start, now, tmp;
  54
  55         while (usec > 0) {
  56                 if (usec > 65000)
  57                         tmp = 65000;
  58                 else
  59                         tmp = usec;
  60                 usec = usec - tmp;
  61
  62                 /* Set up TIMER 3 as timebase clock */
  63                 timerp->timer_tmr = MCFTIMER_TMR_DISABLE;
  64                 timerp->timer_tcn = 0;
  65                 /* set period to 1 us */
  66                 timerp->timer_tmr = (((CFG_CLK / 1000000) - 1)  << 8) | MCFTIMER_TMR_CLK1 |
  67                                      MCFTIMER_TMR_FREERUN | MCFTIMER_TMR_ENABLE;
  68
  69                 start = now = timerp->timer_tcn;
  70                 while (now < start + tmp)
  71                         now = timerp->timer_tcn;
  72         }
  73 }
  74
  75 void mcf_timer_interrupt (void * not_used){
  76         volatile timer_t *timerp = (timer_t *) (CFG_MBAR + MCFTIMER_BASE4);
  77         volatile intctrl_t *intp = (intctrl_t *) (CFG_MBAR + MCFSIM_ICR1);
  78
  79         /* check for timer 4 interrupts */
  80         if ((intp->int_isr & 0x01000000) != 0) {
  81                 return;
  82         }
  83
  84         /* reset timer */
  85         timerp->timer_ter = MCFTIMER_TER_CAP | MCFTIMER_TER_REF;
  86         timestamp ++;
  87 }
  88
  89 void timer_init (void) {
  90         volatile timer_t *timerp = (timer_t *) (CFG_MBAR + MCFTIMER_BASE4);
  91         volatile intctrl_t *intp = (intctrl_t *) (CFG_MBAR + MCFSIM_ICR1);
  92
  93         timestamp = 0;
  94
  95         /* Set up TIMER 4 as clock */
  96         timerp->timer_tmr = MCFTIMER_TMR_DISABLE;
  97
  98         /* initialize and enable timer 4 interrupt */
  99         irq_install_handler (72, mcf_timer_interrupt, 0);
 100         intp->int_icr1 |= 0x0000000d;
 101
 102         timerp->timer_tcn = 0;
 103         timerp->timer_trr = 1000;       /* Interrupt every ms */
 104         /* set a period of 1us, set timer mode to restart and enable timer and interrupt */
 105         timerp->timer_tmr = (((CFG_CLK / 1000000) - 1)  << 8) | MCFTIMER_TMR_CLK1 |
 106                 MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENORI | MCFTIMER_TMR_ENABLE;
 107 }
 108
 109 void reset_timer (void)
 110 {
 111         timestamp = 0;
 112 }
 113
 114 ulong get_timer (ulong base)
 115 {
 116         return (timestamp - base);
 117 }
 118
 119 void set_timer (ulong t)
 120 {
 121         timestamp = t;
 122 }
 123 #endif
 124
 125 #if defined(CONFIG_M5282)
 126
 127 void udelay(unsigned long usec)
 128 {
 129 }
 130
 131 void timer_init (void)
 132 {
 133         volatile unsigned short *timerp;
 134
 135         timerp = (volatile unsigned short *) (CFG_MBAR + MCFTIMER_BASE4);
 136         timestamp = 0;
 137
 138         /* Set up TIMER 4 as poll clock */
 139         timerp[MCFTIMER_PCSR] = MCFTIMER_PCSR_OVW;
 140         timerp[MCFTIMER_PMR] = lastinc = 0;
 141         timerp[MCFTIMER_PCSR] =
 142                 (5 << 8) | MCFTIMER_PCSR_EN | MCFTIMER_PCSR_OVW;
 143 }
 144
 145 void set_timer (ulong t)
 146 {
 147         volatile unsigned short *timerp;
 148
 149         timerp = (volatile unsigned short *) (CFG_MBAR + MCFTIMER_BASE4);
 150         timestamp = 0;
 151         timerp[MCFTIMER_PMR] = lastinc = 0;
 152 }
 153
 154 ulong get_timer (ulong base)
 155 {
 156         unsigned short now, diff;
 157         volatile unsigned short *timerp;
 158
 159         timerp = (volatile unsigned short *) (CFG_MBAR + MCFTIMER_BASE4);
 160         now = timerp[MCFTIMER_PCNTR];
 161         diff = -(now - lastinc);
 162
 163         timestamp += diff;
 164         lastinc = now;
 165         return timestamp - base;
 166 }
 167
 168 void wait_ticks (unsigned long ticks)
 169 {
 170         set_timer (0);
 171         while (get_timer (0) < ticks);
 172 }
 173 #endif