1 /* arch/arm/mach-s3c2410/include/mach/system-reset.h 2 * 3 * Copyright (c) 2008 Simtec Electronics 4 * Ben Dooks <ben@simtec.co.uk> 5 * 6 * S3C2410 - System define for arch_reset() function 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 <mach/hardware.h> 14 #include <linux/io.h> 15 16 #include <plat/regs-watchdog.h> 17 #include <mach/regs-clock.h> 18 19 #include <linux/clk.h> 20 #include <linux/err.h> 21 22 extern void (*s3c24xx_reset_hook)(void); 23 24 static void arch_reset(char mode)25arch_reset(char mode) 26 { 27 struct clk *wdtclk; 28 29 if (mode == 's') { 30 cpu_reset(0); 31 } 32 33 if (s3c24xx_reset_hook) 34 s3c24xx_reset_hook(); 35 36 printk("arch_reset: attempting watchdog reset\n"); 37 38 __raw_writel(0, S3C2410_WTCON); /* disable watchdog, to be safe */ 39 40 wdtclk = clk_get(NULL, "watchdog"); 41 if (!IS_ERR(wdtclk)) { 42 clk_enable(wdtclk); 43 } else 44 printk(KERN_WARNING "%s: warning: cannot get watchdog clock\n", __func__); 45 46 /* put initial values into count and data */ 47 __raw_writel(0x80, S3C2410_WTCNT); 48 __raw_writel(0x80, S3C2410_WTDAT); 49 50 /* set the watchdog to go and reset... */ 51 __raw_writel(S3C2410_WTCON_ENABLE|S3C2410_WTCON_DIV16|S3C2410_WTCON_RSTEN | 52 S3C2410_WTCON_PRESCALE(0x20), S3C2410_WTCON); 53 54 /* wait for reset to assert... */ 55 mdelay(500); 56 57 printk(KERN_ERR "Watchdog reset failed to assert reset\n"); 58 59 /* delay to allow the serial port to show the message */ 60 mdelay(50); 61 62 /* we'll take a jump through zero as a poor second */ 63 cpu_reset(0); 64 } 65