include/asm-arm/arch-s3c2410/uncompress.h

   1 /* linux/include/asm-arm/arch-s3c2410/uncompress.h
   2  *
   3  * (c) 2003 Simtec Electronics
   4  *    Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * S3C2410 - uncompress code
   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  * Changelog:
  13  *  22-May-2003 BJD  Created
  14  *  08-Sep-2003 BJD  Moved to linux v2.6
  15  *  12-Mar-2004 BJD  Updated header protection
  16  *  12-Oct-2004 BJD  Take account of debug uart configuration
  17  *  15-Nov-2004 BJD  Fixed uart configuration
  18  *  22-Feb-2005 BJD  Added watchdog to uncompress
  19 */
  20
  21 #ifndef __ASM_ARCH_UNCOMPRESS_H
  22 #define __ASM_ARCH_UNCOMPRESS_H
  23
  24 #include <linux/config.h>
  25
  26 /* defines for UART registers */
  27 #include "asm/arch/regs-serial.h"
  28 #include "asm/arch/regs-gpio.h"
  29 #include "asm/arch/regs-watchdog.h"
  30
  31 #include <asm/arch/map.h>
  32
  33 /* working in physical space... */
  34 #undef S3C2410_GPIOREG
  35 #undef S3C2410_WDOGREG
  36
  37 #define S3C2410_GPIOREG(x) ((S3C2410_PA_GPIO + (x)))
  38 #define S3C2410_WDOGREG(x) ((S3C2410_PA_WATCHDOG + (x)))
  39
  40 /* how many bytes we allow into the FIFO at a time in FIFO mode */
  41 #define FIFO_MAX         (14)
  42
  43 #define uart_base S3C2410_PA_UART + (0x4000*CONFIG_S3C2410_LOWLEVEL_UART_PORT)
  44
  45 static __inline__ void
  46 uart_wr(unsigned int reg, unsigned int val)
  47 {
  48         volatile unsigned int *ptr;
  49
  50         ptr = (volatile unsigned int *)(reg + uart_base);
  51         *ptr = val;
  52 }
  53
  54 static __inline__ unsigned int
  55 uart_rd(unsigned int reg)
  56 {
  57         volatile unsigned int *ptr;
  58
  59         ptr = (volatile unsigned int *)(reg + uart_base);
  60         return *ptr;
  61 }
  62
  63
  64 /* we can deal with the case the UARTs are being run
  65  * in FIFO mode, so that we don't hold up our execution
  66  * waiting for tx to happen...
  67 */
  68
  69 static void
  70 putc(char ch)
  71 {
  72         int cpuid = *((volatile unsigned int *)S3C2410_GSTATUS1);
  73
  74         cpuid &= S3C2410_GSTATUS1_IDMASK;
  75
  76         if (ch == '\n')
  77                 putc('\r');    /* expand newline to \r\n */
  78
  79         if (uart_rd(S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE) {
  80                 int level;
  81
  82                 while (1) {
  83                         level = uart_rd(S3C2410_UFSTAT);
  84
  85                         if (cpuid == S3C2410_GSTATUS1_2440) {
  86                                 level &= S3C2440_UFSTAT_TXMASK;
  87                                 level >>= S3C2440_UFSTAT_TXSHIFT;
  88                         } else {
  89                                 level &= S3C2410_UFSTAT_TXMASK;
  90                                 level >>= S3C2410_UFSTAT_TXSHIFT;
  91                         }
  92
  93                         if (level < FIFO_MAX)
  94                                 break;
  95                 }
  96
  97         } else {
  98                 /* not using fifos */
  99
 100                 while ((uart_rd(S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE) != S3C2410_UTRSTAT_TXE);
 101         }
 102
 103         /* write byte to transmission register */
 104         uart_wr(S3C2410_UTXH, ch);
 105 }
 106
 107 static void
 108 putstr(const char *ptr)
 109 {
 110         for (; *ptr != '\0'; ptr++) {
 111                 putc(*ptr);
 112         }
 113 }
 114
 115 /* CONFIG_S3C2410_BOOT_WATCHDOG
 116  *
 117  * Simple boot-time watchdog setup, to reboot the system if there is
 118  * any problem with the boot process
 119 */
 120
 121 #ifdef CONFIG_S3C2410_BOOT_WATCHDOG
 122
 123 #define WDOG_COUNT (0xff00)
 124
 125 #define __raw_writel(d,ad) do { *((volatile unsigned int *)(ad)) = (d); } while(0)
 126
 127 static inline void arch_decomp_wdog(void)
 128 {
 129         __raw_writel(WDOG_COUNT, S3C2410_WTCNT);
 130 }
 131
 132 static void arch_decomp_wdog_start(void)
 133 {
 134         __raw_writel(WDOG_COUNT, S3C2410_WTDAT);
 135         __raw_writel(WDOG_COUNT, S3C2410_WTCNT);
 136         __raw_writel(S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128 | S3C2410_WTCON_RSTEN | S3C2410_WTCON_PRESCALE(0x40), S3C2410_WTCON);
 137 }
 138
 139 #else
 140 #define arch_decomp_wdog_start()
 141 #define arch_decomp_wdog()
 142 #endif
 143
 144 static void error(char *err);
 145
 146 static void
 147 arch_decomp_setup(void)
 148 {
 149         /* we may need to setup the uart(s) here if we are not running
 150          * on an BAST... the BAST will have left the uarts configured
 151          * after calling linux.
 152          */
 153
 154         arch_decomp_wdog_start();
 155 }
 156
 157
 158 #endif /* __ASM_ARCH_UNCOMPRESS_H */