arch/m68k/cpu/mcf523x/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  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <asm-offsets.h>
   9 #include <config.h>
  10 #include "version.h"
  11 #include <asm/cache.h>
  12
  13 #ifndef  CONFIG_IDENT_STRING
  14 #define  CONFIG_IDENT_STRING ""
  15 #endif
  16
  17 #define _START  _start
  18 #define _FAULT  _fault
  19
  20 #define SAVE_ALL                                                \
  21         move.w  #0x2700,%sr;            /* disable intrs */     \
  22         subl    #60,%sp;                /* space for 15 regs */ \
  23         moveml  %d0-%d7/%a0-%a6,%sp@;
  24
  25 #define RESTORE_ALL                                             \
  26         moveml  %sp@,%d0-%d7/%a0-%a6;                           \
  27         addl    #60,%sp;                /* space for 15 regs */ \
  28         rte;
  29
  30 .text
  31 /*
  32  *      Vector table. This is used for initial platform startup.
  33  *      These vectors are to catch any un-intended traps.
  34  */
  35 _vectors:
  36
  37 INITSP:         .long   0x00000000      /* Initial SP   */
  38 INITPC:         .long   _START  /* Initial PC           */
  39 vector02:       .long   _FAULT  /* Access Error         */
  40 vector03:       .long   _FAULT  /* Address Error        */
  41 vector04:       .long   _FAULT  /* Illegal Instruction  */
  42 vector05:       .long   _FAULT  /* Reserved             */
  43 vector06:       .long   _FAULT  /* Reserved             */
  44 vector07:       .long   _FAULT  /* Reserved             */
  45 vector08:       .long   _FAULT  /* Privilege Violation  */
  46 vector09:       .long   _FAULT  /* Trace                */
  47 vector0A:       .long   _FAULT  /* Unimplemented A-Line */
  48 vector0B:       .long   _FAULT  /* Unimplemented F-Line */
  49 vector0C:       .long   _FAULT  /* Debug Interrupt      */
  50 vector0D:       .long   _FAULT  /* Reserved             */
  51 vector0E:       .long   _FAULT  /* Format Error         */
  52 vector0F:       .long   _FAULT  /* Unitialized Int.     */
  53
  54 /* Reserved */
  55 vector10_17:
  56 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  57
  58 vector18:       .long   _FAULT  /* Spurious Interrupt   */
  59 vector19:       .long   _FAULT  /* Autovector Level 1   */
  60 vector1A:       .long   _FAULT  /* Autovector Level 2   */
  61 vector1B:       .long   _FAULT  /* Autovector Level 3   */
  62 vector1C:       .long   _FAULT  /* Autovector Level 4   */
  63 vector1D:       .long   _FAULT  /* Autovector Level 5   */
  64 vector1E:       .long   _FAULT  /* Autovector Level 6   */
  65 vector1F:       .long   _FAULT  /* Autovector Level 7   */
  66
  67 /* TRAP #0 - #15 */
  68 vector20_2F:
  69 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  70 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  71
  72 /* Reserved     */
  73 vector30_3F:
  74 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  75 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  76
  77 vector64_127:
  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 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  84 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  85 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  86
  87 vector128_191:
  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 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  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
  97 vector192_255:
  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 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
 102 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
 103 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
 104 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
 105 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
 106
 107         .text
 108
 109         .globl  _start
 110 _start:
 111         nop
 112         nop
 113         move.w #0x2700,%sr      /* Mask off Interrupt */
 114
 115         /* Set vector base register at the beginning of the Flash */
 116         move.l  #CONFIG_SYS_FLASH_BASE, %d0
 117         movec   %d0, %VBR
 118
 119         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_CTRL), %d0
 120         movec   %d0, %RAMBAR1
 121
 122         /* invalidate and disable cache */
 123         move.l  #CF_CACR_CINV, %d0              /* Invalidate cache cmd */
 124         movec   %d0, %CACR                      /* Invalidate cache */
 125         nop
 126         move.l  #0, %d0
 127         movec   %d0, %ACR0
 128         movec   %d0, %ACR1
 129
 130         /* initialize general use internal ram */
 131         move.l #0, %d0
 132         move.l #(ICACHE_STATUS), %a1    /* icache */
 133         move.l #(DCACHE_STATUS), %a2    /* icache */
 134         move.l %d0, (%a1)
 135         move.l %d0, (%a2)
 136
 137         /* set stackpointer to end of internal ram to get some stackspace for the
 138            first c-code */
 139         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_SP_OFFSET), %sp
 140         clr.l %sp@-
 141
 142         move.l #__got_start, %a5        /* put relocation table address to a5 */
 143
 144         bsr cpu_init_f                  /* run low-level CPU init code (from flash) */
 145         bsr board_init_f                /* run low-level board init code (from flash) */
 146
 147         /* board_init_f() does not return */
 148
 149 /*------------------------------------------------------------------------------*/
 150
 151 /*
 152  * void relocate_code (addr_sp, gd, addr_moni)
 153  *
 154  * This "function" does not return, instead it continues in RAM
 155  * after relocating the monitor code.
 156  *
 157  * r3 = dest
 158  * r4 = src
 159  * r5 = length in bytes
 160  * r6 = cachelinesize
 161  */
 162         .globl  relocate_code
 163 relocate_code:
 164         link.w %a6,#0
 165         move.l 8(%a6), %sp              /* set new stack pointer */
 166
 167         move.l 12(%a6), %d0             /* Save copy of Global Data pointer */
 168         move.l 16(%a6), %a0             /* Save copy of Destination Address */
 169
 170         move.l #CONFIG_SYS_MONITOR_BASE, %a1
 171         move.l #__init_end, %a2
 172         move.l %a0, %a3
 173
 174         /* copy the code to RAM */
 175 1:
 176         move.l (%a1)+, (%a3)+
 177         cmp.l  %a1,%a2
 178         bgt.s    1b
 179
 180 /*
 181  * We are done. Do not return, instead branch to second part of board
 182  * initialization, now running from RAM.
 183  */
 184         move.l  %a0, %a1
 185         add.l   #(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
 186         jmp     (%a1)
 187
 188 in_ram:
 189
 190 clear_bss:
 191         /*
 192          * Now clear BSS segment
 193          */
 194         move.l  %a0, %a1
 195         add.l   #(_sbss - CONFIG_SYS_MONITOR_BASE),%a1
 196         move.l  %a0, %d1
 197         add.l   #(_ebss - CONFIG_SYS_MONITOR_BASE),%d1
 198 6:
 199         clr.l   (%a1)+
 200         cmp.l   %a1,%d1
 201         bgt.s   6b
 202
 203         /*
 204          * fix got table in RAM
 205          */
 206         move.l  %a0, %a1
 207         add.l   #(__got_start - CONFIG_SYS_MONITOR_BASE),%a1
 208         move.l  %a1,%a5         /* * fix got pointer register a5 */
 209
 210         move.l  %a0, %a2
 211         add.l   #(__got_end - CONFIG_SYS_MONITOR_BASE),%a2
 212
 213 7:
 214         move.l  (%a1),%d1
 215         sub.l   #_start,%d1
 216         add.l   %a0,%d1
 217         move.l  %d1,(%a1)+
 218         cmp.l   %a2, %a1
 219         bne     7b
 220
 221         /* calculate relative jump to board_init_r in ram */
 222         move.l %a0, %a1
 223         add.l #(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
 224
 225         /* set parameters for board_init_r */
 226         move.l %a0,-(%sp)               /* dest_addr */
 227         move.l %d0,-(%sp)               /* gd */
 228         jsr     (%a1)
 229
 230 /*------------------------------------------------------------------------------*/
 231 /* exception code */
 232         .globl _fault
 233 _fault:
 234         bra _fault
 235         .globl  _exc_handler
 236
 237 _exc_handler:
 238         SAVE_ALL
 239         movel   %sp,%sp@-
 240         bsr exc_handler
 241         addql   #4,%sp
 242         RESTORE_ALL
 243
 244         .globl  _int_handler
 245 _int_handler:
 246         SAVE_ALL
 247         movel   %sp,%sp@-
 248         bsr int_handler
 249         addql   #4,%sp
 250         RESTORE_ALL
 251
 252 /*------------------------------------------------------------------------------*/
 253
 254         .globl  version_string
 255 version_string:
 256         .ascii U_BOOT_VERSION_STRING, "\0"
 257         .align 4