cpu/arm920t/imx/interrupts.c

   1 /*
   2  * (C) Copyright 2002
   3  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   4  * Marius Groeger <mgroeger@sysgo.de>
   5  *
   6  * (C) Copyright 2002
   7  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   8  * Alex Zuepke <azu@sysgo.de>
   9  *
  10  * (C) Copyright 2002
  11  * Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
  12  *
  13  * See file CREDITS for list of people who contributed to this
  14  * project.
  15  *
  16  * This program is free software; you can redistribute it and/or
  17  * modify it under the terms of the GNU General Public License as
  18  * published by the Free Software Foundation; either version 2 of
  19  * the License, or (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  29  * MA 02111-1307 USA
  30  */
  31
  32 #include <common.h>
  33 #if defined (CONFIG_IMX)
  34
  35 #include <arm920t.h>
  36 #include <asm/arch/imx-regs.h>
  37
  38 int interrupt_init (void)
  39 {
  40         int i;
  41         /* setup GP Timer 1 */
  42         TCTL1 = TCTL_SWR;
  43         for ( i=0; i<100; i++) TCTL1 = 0; /* We have no udelay by now */
  44         TPRER1 = get_PERCLK1() / 1000000; /* 1 MHz */
  45         TCTL1 |= TCTL_FRR | (1<<1); /* Freerun Mode, PERCLK1 input */
  46
  47         reset_timer_masked();
  48
  49         return (0);
  50 }
  51
  52 /*
  53  * timer without interrupts
  54  */
  55
  56 void reset_timer (void)
  57 {
  58         reset_timer_masked ();
  59 }
  60
  61 ulong get_timer (ulong base)
  62 {
  63         return get_timer_masked() - base;
  64 }
  65
  66 void set_timer (ulong t)
  67 {
  68         /* nop */
  69 }
  70
  71 void reset_timer_masked (void)
  72 {
  73         TCTL1 &= ~TCTL_TEN;
  74         TCTL1 |= TCTL_TEN; /* Enable timer */
  75 }
  76
  77 ulong get_timer_masked (void)
  78 {
  79         return TCN1;
  80 }
  81
  82 void udelay_masked (unsigned long usec)
  83 {
  84         ulong endtime = get_timer_masked() + usec;
  85         signed long diff;
  86
  87         do {
  88                 ulong now = get_timer_masked ();
  89                 diff = endtime - now;
  90         } while (diff >= 0);
  91 }
  92
  93 void udelay (unsigned long usec)
  94 {
  95         udelay_masked(usec);
  96 }
  97
  98 /*
  99  * This function is derived from PowerPC code (read timebase as long long).
 100  * On ARM it just returns the timer value.
 101  */
 102 unsigned long long get_ticks(void)
 103 {
 104         return get_timer(0);
 105 }
 106
 107 /*
 108  * This function is derived from PowerPC code (timebase clock frequency).
 109  * On ARM it returns the number of timer ticks per second.
 110  */
 111 ulong get_tbclk (void)
 112 {
 113         ulong tbclk;
 114
 115         tbclk = CONFIG_SYS_HZ;
 116
 117         return tbclk;
 118 }
 119
 120 /*
 121  * Reset the cpu by setting up the watchdog timer and let him time out
 122  */
 123 void reset_cpu (ulong ignored)
 124 {
 125         /* Disable watchdog and set Time-Out field to 0 */
 126         WCR = 0x00000000;
 127
 128         /* Write Service Sequence */
 129         WSR = 0x00005555;
 130         WSR = 0x0000AAAA;
 131
 132         /* Enable watchdog */
 133         WCR = 0x00000001;
 134
 135         while (1);
 136         /*NOTREACHED*/
 137 }
 138
 139 #endif /* defined (CONFIG_IMX) */