arch/m68k/cpu/mcf52x2/start.S

   1 /*
   2  * Copyright (C) 2003   Josef Baumgartner <josef.baumgartner@telex.de>
   3  * Based on code from Bernhard Kuhn <bkuhn@metrowerks.com>
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <asm-offsets.h>
  25 #include <config.h>
  26 #include "version.h"
  27 #include <asm/cache.h>
  28
  29 #ifndef  CONFIG_IDENT_STRING
  30 #define  CONFIG_IDENT_STRING ""
  31 #endif
  32
  33 #define _START  _start
  34 #define _FAULT  _fault
  35
  36
  37 #define SAVE_ALL                                                \
  38         move.w  #0x2700,%sr;            /* disable intrs */     \
  39         subl    #60,%sp;                /* space for 15 regs */ \
  40         moveml  %d0-%d7/%a0-%a6,%sp@;                           \
  41
  42 #define RESTORE_ALL                                             \
  43         moveml  %sp@,%d0-%d7/%a0-%a6;                           \
  44         addl    #60,%sp;                /* space for 15 regs */ \
  45         rte
  46
  47 /* If we come from a pre-loader we don't need an initial exception
  48  * table.
  49  */
  50 #if !defined(CONFIG_MONITOR_IS_IN_RAM)
  51
  52 .text
  53 /*
  54  *      Vector table. This is used for initial platform startup.
  55  *      These vectors are to catch any un-intended traps.
  56  */
  57 _vectors:
  58
  59 .long   0x00000000              /* Flash offset is 0 until we setup CS0 */
  60 #if defined(CONFIG_M5282) && (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
  61 .long   _start - CONFIG_SYS_TEXT_BASE
  62 #else
  63 .long   _START
  64 #endif
  65
  66 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  67 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  68 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  69 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  70 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  71 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  72 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  73 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  74
  75 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  76 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  77 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  78 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  79 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  80 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  81 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  82 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  83
  84 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  85 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  86 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  87 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  88 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  89 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  90 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  91 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  92
  93 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  94 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  95 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  96 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  97 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  98 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  99 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
 100 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
 101
 102 #endif
 103
 104         .text
 105
 106
 107 #if defined(CONFIG_SYS_INT_FLASH_BASE) && \
 108     (defined(CONFIG_M5282) || defined(CONFIG_M5281))
 109         #if (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
 110                 .long   0x55AA55AA,0xAA55AA55 /* CFM Backdoorkey */
 111                 .long   0xFFFFFFFF /* all sectors protected */
 112                 .long   0x00000000 /* supervisor/User restriction */
 113                 .long   0x00000000 /* programm/data space restriction */
 114                 .long   0x00000000 /* Flash security */
 115         #endif
 116 #endif
 117         .globl  _start
 118 _start:
 119         nop
 120         nop
 121         move.w #0x2700,%sr
 122
 123 #if defined(CONFIG_M5208)
 124         /* Initialize RAMBAR: locate SRAM and validate it */
 125         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_CTRL), %d0
 126         movec   %d0, %RAMBAR1
 127 #endif
 128
 129 #if defined(CONFIG_M5272) || defined(CONFIG_M5249) || defined(CONFIG_M5253)
 130         move.l  #(CONFIG_SYS_MBAR + 1), %d0             /* set MBAR address + valid flag */
 131         move.c  %d0, %MBAR
 132
 133         /*** The 5249 has MBAR2 as well ***/
 134 #ifdef CONFIG_SYS_MBAR2
 135         move.l  #(CONFIG_SYS_MBAR2 + 1), %d0            /* Get MBAR2 address */
 136         movec   %d0, #0xc0e                     /* Set MBAR2 */
 137 #endif
 138
 139         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + 1), %d0
 140         movec   %d0, %RAMBAR0
 141 #endif /* CONFIG_M5272 || CONFIG_M5249 || CONFIG_M5253 */
 142
 143 #if defined(CONFIG_M5282) || defined(CONFIG_M5271)
 144         /* Initialize IPSBAR */
 145         move.l  #(CONFIG_SYS_MBAR + 1), %d0             /* set IPSBAR address + valid flag */
 146         move.l  %d0, 0x40000000
 147
 148         /* Initialize RAMBAR1: locate SRAM and validate it */
 149         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + 0x21), %d0
 150         movec   %d0, %RAMBAR1
 151
 152 #if defined(CONFIG_M5282)
 153 #if (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
 154         /* Setup code in SRAM to initialize FLASHBAR, if start from internal Flash */
 155
 156         move.l #(_flashbar_setup-CONFIG_SYS_INT_FLASH_BASE), %a0
 157         move.l #(_flashbar_setup_end-CONFIG_SYS_INT_FLASH_BASE), %a1
 158         move.l #(CONFIG_SYS_INIT_RAM_ADDR), %a2
 159 _copy_flash:
 160         move.l (%a0)+, (%a2)+
 161         cmp.l %a0, %a1
 162         bgt.s _copy_flash
 163         jmp CONFIG_SYS_INIT_RAM_ADDR
 164
 165 _flashbar_setup:
 166         /* Initialize FLASHBAR: locate internal Flash and validate it */
 167         move.l  #(CONFIG_SYS_INT_FLASH_BASE + CONFIG_SYS_INT_FLASH_ENABLE), %d0
 168         movec   %d0, %FLASHBAR
 169         jmp _after_flashbar_copy.L      /* Force jump to absolute address */
 170 _flashbar_setup_end:
 171         nop
 172 _after_flashbar_copy:
 173 #else
 174         /* Setup code to initialize FLASHBAR, if start from external Memory */
 175         move.l  #(CONFIG_SYS_INT_FLASH_BASE + CONFIG_SYS_INT_FLASH_ENABLE), %d0
 176         movec   %d0, %FLASHBAR
 177 #endif /* (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE) */
 178
 179 #endif
 180 #endif
 181         /* if we come from a pre-loader we have no exception table and
 182          * therefore no VBR to set
 183          */
 184 #if !defined(CONFIG_MONITOR_IS_IN_RAM)
 185 #if defined(CONFIG_M5282) && (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
 186         move.l  #CONFIG_SYS_INT_FLASH_BASE, %d0
 187 #else
 188         move.l  #CONFIG_SYS_FLASH_BASE, %d0
 189 #endif
 190         movec   %d0, %VBR
 191 #endif
 192
 193 #ifdef CONFIG_M5275
 194         /* Initialize IPSBAR */
 195         move.l  #(CONFIG_SYS_MBAR + 1), %d0             /* set IPSBAR address + valid flag */
 196         move.l  %d0, 0x40000000
 197 /*      movec   %d0, %MBAR */
 198
 199         /* Initialize RAMBAR: locate SRAM and validate it */
 200         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + 0x21), %d0
 201         movec   %d0, %RAMBAR1
 202 #endif
 203
 204         /* initialize general use internal ram */
 205         move.l #0, %d0
 206         move.l #(ICACHE_STATUS), %a1    /* icache */
 207         move.l #(DCACHE_STATUS), %a2    /* icache */
 208         move.l %d0, (%a1)
 209         move.l %d0, (%a2)
 210
 211         /* set stackpointer to end of internal ram to get some stackspace for the first c-code */
 212         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_SP_OFFSET), %sp
 213         clr.l %sp@-
 214
 215         move.l #__got_start, %a5                /* put relocation table address to a5 */
 216
 217         bsr cpu_init_f                          /* run low-level CPU init code (from flash) */
 218         bsr board_init_f                        /* run low-level board init code (from flash) */
 219
 220         /* board_init_f() does not return */
 221
 222 /*------------------------------------------------------------------------------*/
 223
 224 /*
 225  * void relocate_code (addr_sp, gd, addr_moni)
 226  *
 227  * This "function" does not return, instead it continues in RAM
 228  * after relocating the monitor code.
 229  *
 230  * r3 = dest
 231  * r4 = src
 232  * r5 = length in bytes
 233  * r6 = cachelinesize
 234  */
 235         .globl  relocate_code
 236 relocate_code:
 237         link.w %a6,#0
 238         move.l 8(%a6), %sp              /* set new stack pointer */
 239
 240         move.l 12(%a6), %d0             /* Save copy of Global Data pointer */
 241         move.l 16(%a6), %a0             /* Save copy of Destination Address */
 242
 243         move.l #CONFIG_SYS_MONITOR_BASE, %a1
 244         move.l #__init_end, %a2
 245         move.l %a0, %a3
 246         /* copy the code to RAM */
 247 1:
 248         move.l (%a1)+, (%a3)+
 249         cmp.l  %a1,%a2
 250         bgt.s    1b
 251
 252 /*
 253  * We are done. Do not return, instead branch to second part of board
 254  * initialization, now running from RAM.
 255  */
 256         move.l  %a0, %a1
 257         add.l   #(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
 258         jmp     (%a1)
 259
 260 in_ram:
 261
 262 clear_bss:
 263         /*
 264          * Now clear BSS segment
 265          */
 266         move.l  %a0, %a1
 267         add.l   #(_sbss - CONFIG_SYS_MONITOR_BASE),%a1
 268         move.l  %a0, %d1
 269         add.l   #(_ebss - CONFIG_SYS_MONITOR_BASE),%d1
 270 6:
 271         clr.l   (%a1)+
 272         cmp.l   %a1,%d1
 273         bgt.s   6b
 274
 275         /*
 276          * fix got table in RAM
 277          */
 278         move.l  %a0, %a1
 279         add.l   #(__got_start - CONFIG_SYS_MONITOR_BASE),%a1
 280         move.l  %a1,%a5         /* * fix got pointer register a5 */
 281
 282         move.l  %a0, %a2
 283         add.l   #(__got_end - CONFIG_SYS_MONITOR_BASE),%a2
 284
 285 7:
 286         move.l  (%a1),%d1
 287         sub.l   #_start,%d1
 288         add.l   %a0,%d1
 289         move.l  %d1,(%a1)+
 290         cmp.l   %a2, %a1
 291         bne     7b
 292
 293         /* calculate relative jump to board_init_r in ram */
 294         move.l %a0, %a1
 295         add.l #(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
 296
 297         /* set parameters for board_init_r */
 298         move.l %a0,-(%sp)               /* dest_addr */
 299         move.l %d0,-(%sp)               /* gd */
 300 #if defined(DEBUG) && (CONFIG_SYS_TEXT_BASE != CONFIG_SYS_INT_FLASH_BASE) && \
 301     defined(CONFIG_SYS_HALT_BEFOR_RAM_JUMP)
 302         halt
 303 #endif
 304         jsr     (%a1)
 305
 306 /*------------------------------------------------------------------------------*/
 307 /* exception code */
 308         .globl _fault
 309 _fault:
 310         bra _fault
 311
 312         .globl  _exc_handler
 313 _exc_handler:
 314         SAVE_ALL
 315         movel   %sp,%sp@-
 316         bsr exc_handler
 317         addql   #4,%sp
 318         RESTORE_ALL
 319
 320         .globl  _int_handler
 321 _int_handler:
 322         SAVE_ALL
 323         movel   %sp,%sp@-
 324         bsr int_handler
 325         addql   #4,%sp
 326         RESTORE_ALL
 327
 328 /*------------------------------------------------------------------------------*/
 329
 330         .globl  version_string
 331 version_string:
 332         .ascii U_BOOT_VERSION_STRING, "\0"
 333         .align 4