arch/blackfin/lib/boot.c

   1 /*
   2  * U-Boot - boot.c - misc boot helper functions
   3  *
   4  * Copyright (c) 2005-2008 Analog Devices Inc.
   5  *
   6  * (C) Copyright 2000-2004
   7  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   8  *
   9  * Licensed under the GPL-2 or later.
  10  */
  11
  12 #include <common.h>
  13 #include <command.h>
  14 #include <image.h>
  15 #include <asm/blackfin.h>
  16
  17 #ifdef SHARED_RESOURCES
  18 extern void swap_to(int device_id);
  19 #endif
  20
  21 #ifdef CONFIG_VIDEO
  22 extern void video_stop(void);
  23 #endif
  24
  25 static char *make_command_line(void)
  26 {
  27         char *dest = (char *)CONFIG_LINUX_CMDLINE_ADDR;
  28         char *bootargs = getenv("bootargs");
  29
  30         if (bootargs == NULL)
  31                 return NULL;
  32
  33         strncpy(dest, bootargs, CONFIG_LINUX_CMDLINE_SIZE);
  34         dest[CONFIG_LINUX_CMDLINE_SIZE - 1] = 0;
  35         return dest;
  36 }
  37
  38 extern ulong bfin_poweron_retx;
  39
  40 int do_bootm_linux(int flag, int argc, char * const argv[], bootm_headers_t *images)
  41 {
  42         int     (*appl) (char *cmdline);
  43         char    *cmdline;
  44
  45         if (flag & BOOTM_STATE_OS_PREP)
  46                 return 0;
  47         if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
  48                 return 1;
  49
  50 #ifdef SHARED_RESOURCES
  51         swap_to(FLASH);
  52 #endif
  53
  54 #ifdef CONFIG_VIDEO
  55         /* maybe this should be standardized and moved to bootm ... */
  56         video_stop();
  57 #endif
  58
  59         appl = (int (*)(char *))images->ep;
  60
  61         printf("Starting Kernel at = %p\n", appl);
  62         cmdline = make_command_line();
  63         icache_disable();
  64         dcache_disable();
  65         asm __volatile__(
  66                 "RETX = %[retx];"
  67                 "CALL (%0);"
  68                 :
  69                 : "p"(appl), "q0"(cmdline), [retx] "d"(bfin_poweron_retx)
  70         );
  71         /* does not return */
  72
  73         return 1;
  74 }