arch/arm/mach-s3c2410/include/mach/system.h

   1 /* arch/arm/mach-s3c2410/include/mach/system.h
   2  *
   3  * Copyright (c) 2003 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * S3C2410 - System function defines and includes
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11 */
  12
  13 #include <linux/io.h>
  14 #include <mach/hardware.h>
  15
  16 #include <mach/map.h>
  17 #include <mach/idle.h>
  18
  19 #include <mach/regs-clock.h>
  20
  21 void (*s3c24xx_idle)(void);
  22
  23 void s3c24xx_default_idle(void)
  24 {
  25         unsigned long tmp;
  26         int i;
  27
  28         /* idle the system by using the idle mode which will wait for an
  29          * interrupt to happen before restarting the system.
  30          */
  31
  32         /* Warning: going into idle state upsets jtag scanning */
  33
  34         __raw_writel(__raw_readl(S3C2410_CLKCON) | S3C2410_CLKCON_IDLE,
  35                      S3C2410_CLKCON);
  36
  37         /* the samsung port seems to do a loop and then unset idle.. */
  38         for (i = 0; i < 50; i++) {
  39                 tmp += __raw_readl(S3C2410_CLKCON); /* ensure loop not optimised out */
  40         }
  41
  42         /* this bit is not cleared on re-start... */
  43
  44         __raw_writel(__raw_readl(S3C2410_CLKCON) & ~S3C2410_CLKCON_IDLE,
  45                      S3C2410_CLKCON);
  46 }
  47
  48 static void arch_idle(void)
  49 {
  50         if (s3c24xx_idle != NULL)
  51                 (s3c24xx_idle)();
  52         else
  53                 s3c24xx_default_idle();
  54 }