arch/arm/cpu/arm920t/at91rm9200/reset.c

   1 /*
   2  * (C) Copyright 2002
   3  * Lineo, Inc. <www.lineo.com>
   4  * Bernhard Kuhn <bkuhn@lineo.com>
   5  *
   6  * (C) Copyright 2002
   7  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   8  * Marius Groeger <mgroeger@sysgo.de>
   9  *
  10  * (C) Copyright 2002
  11  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
  12  * Alex Zuepke <azu@sysgo.de>
  13  *
  14  * See file CREDITS for list of people who contributed to this
  15  * project.
  16  *
  17  * This program is free software; you can redistribute it and/or
  18  * modify it under the terms of the GNU General Public License as
  19  * published by the Free Software Foundation; either version 2 of
  20  * the License, or (at your option) any later version.
  21  *
  22  * This program is distributed in the hope that it will be useful,
  23  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  * GNU General Public License for more details.
  26  *
  27  * You should have received a copy of the GNU General Public License
  28  * along with this program; if not, write to the Free Software
  29  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  30  * MA 02111-1307 USA
  31  */
  32
  33 #include <common.h>
  34 #include <asm/arch/hardware.h>
  35
  36 void board_reset(void) __attribute__((__weak__));
  37
  38 /*
  39  * Reset the cpu by setting up the watchdog timer and let him time out
  40  * or toggle a GPIO pin on the AT91RM9200DK board
  41  */
  42 void reset_cpu (ulong ignored)
  43 {
  44
  45 #if defined(CONFIG_AT91RM9200_USART)
  46         /*shutdown the console to avoid strange chars during reset */
  47         serial_exit();
  48 #endif
  49
  50         if (board_reset)
  51                 board_reset();
  52
  53         /* this is the way Linux does it */
  54
  55         /* FIXME:
  56          * These defines should be moved into
  57          * include/asm-arm/arch-at91rm9200/AT91RM9200.h
  58          * as soon as the whitespace fix gets applied.
  59          */
  60         #define AT91C_ST_RSTEN (0x1 << 16)
  61         #define AT91C_ST_EXTEN (0x1 << 17)
  62         #define AT91C_ST_WDRST (0x1 <<  0)
  63         #define ST_WDMR *((unsigned long *)0xfffffd08)  /* watchdog mode register */
  64         #define ST_CR *((unsigned long *)0xfffffd00)    /* system clock control register */
  65
  66         ST_WDMR = AT91C_ST_RSTEN | AT91C_ST_EXTEN | 1 ;
  67         ST_CR = AT91C_ST_WDRST;
  68
  69         while (1);
  70         /* Never reached */
  71 }