arch/m68k/cpu/mcf523x/start.S

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright (C) 2003   Josef Baumgartner <josef.baumgartner@telex.de>
   4  * Based on code from Bernhard Kuhn <bkuhn@metrowerks.com>
   5  */
   6
   7 #include <asm-offsets.h>
   8 #include <config.h>
   9 #include "version.h"
  10 #include <asm/cache.h>
  11
  12 #define _START  _start
  13 #define _FAULT  _fault
  14
  15 #define SAVE_ALL                                                \
  16         move.w  #0x2700,%sr;            /* disable intrs */     \
  17         subl    #60,%sp;                /* space for 15 regs */ \
  18         moveml  %d0-%d7/%a0-%a6,%sp@;
  19
  20 #define RESTORE_ALL                                             \
  21         moveml  %sp@,%d0-%d7/%a0-%a6;                           \
  22         addl    #60,%sp;                /* space for 15 regs */ \
  23         rte;
  24
  25 .text
  26
  27 /*
  28  * Vector table. This is used for initial platform startup.
  29  * These vectors are to catch any un-intended traps.
  30  */
  31 _vectors:
  32 INITSP: .long   0x00000000              /* Initial SP   */
  33 INITPC: .long   _START                  /* Initial PC   */
  34
  35 vector02_0F:
  36 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  37 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  38
  39 /* Reserved */
  40 vector10_17:
  41 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  42
  43 vector18_1F:
  44 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  45
  46 /* TRAP #0 - #15 */
  47 vector20_2F:
  48 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  49 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  50
  51 /* Reserved     */
  52 vector30_3F:
  53 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  54 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  55
  56 vector64_127:
  57 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  58 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  59 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  60 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  61 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  62 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  63 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  64 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  65
  66 vector128_191:
  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, _FAULT, _FAULT
  74 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  75
  76 vector192_255:
  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 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  84 .long   _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
  85
  86 .text
  87
  88 .globl _start
  89 _start:
  90         nop
  91         nop
  92         move.w  #0x2700,%sr             /* Mask off Interrupt */
  93
  94         /* Set vector base register at the beginning of the Flash */
  95         move.l  #CONFIG_SYS_FLASH_BASE, %d0
  96         movec   %d0, %VBR
  97
  98         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_CTRL), %d0
  99         movec   %d0, %RAMBAR1
 100
 101         /* invalidate and disable cache */
 102         move.l  #CF_CACR_CINV, %d0      /* Invalidate cache cmd */
 103         movec   %d0, %CACR              /* Invalidate cache */
 104         nop
 105         move.l  #0, %d0
 106         movec   %d0, %ACR0
 107         movec   %d0, %ACR1
 108
 109         /* initialize general use internal ram */
 110         move.l  #0, %d0
 111         move.l  #(ICACHE_STATUS), %a1   /* icache */
 112         move.l  #(DCACHE_STATUS), %a2   /* icache */
 113         move.l  %d0, (%a1)
 114         move.l  %d0, (%a2)
 115
 116         /* put relocation table address to a5 */
 117         move.l  #__got_start, %a5
 118
 119         /* setup stack initially on top of internal static ram  */
 120         move.l  #(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_SIZE), %sp
 121
 122         /*
 123          * if configured, malloc_f arena will be reserved first,
 124          * then (and always) gd struct space will be reserved
 125          */
 126         move.l  %sp, -(%sp)
 127         move.l  #board_init_f_alloc_reserve, %a1
 128         jsr     (%a1)
 129
 130         /* update stack and frame-pointers */
 131         move.l  %d0, %sp
 132         move.l  %sp, %fp
 133
 134         /* initialize reserved area */
 135         move.l  %d0, -(%sp)
 136         move.l  #board_init_f_init_reserve, %a1
 137         jsr     (%a1)
 138
 139         /* run low-level CPU init code (from flash) */
 140         move.l  #cpu_init_f, %a1
 141         jsr     (%a1)
 142
 143         /* run low-level board init code (from flash) */
 144         clr.l   %sp@-
 145         move.l  #board_init_f, %a1
 146         jsr     (%a1)
 147
 148         /* board_init_f() does not return */
 149
 150 /******************************************************************************/
 151
 152 /*
 153  * void relocate_code (addr_sp, gd, addr_moni)
 154  *
 155  * This "function" does not return, instead it continues in RAM
 156  * after relocating the monitor code.
 157  *
 158  * r3 = dest
 159  * r4 = src
 160  * r5 = length in bytes
 161  * r6 = cachelinesize
 162  */
 163 .globl relocate_code
 164 relocate_code:
 165         link.w  %a6,#0
 166         move.l  8(%a6), %sp             /* set new stack pointer */
 167
 168         move.l  12(%a6), %d0            /* Save copy of Global Data pointer */
 169         move.l  16(%a6), %a0            /* Save copy of Destination Address */
 170
 171         move.l  #CONFIG_SYS_MONITOR_BASE, %a1
 172         move.l  #__init_end, %a2
 173         move.l  %a0, %a3
 174
 175         /* copy the code to RAM */
 176 1:
 177         move.l  (%a1)+, (%a3)+
 178         cmp.l   %a1,%a2
 179         bgt.s   1b
 180
 181 /*
 182  * We are done. Do not return, instead branch to second part of board
 183  * initialization, now running from RAM.
 184  */
 185         move.l  %a0, %a1
 186         add.l   #(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
 187         jmp     (%a1)
 188
 189 in_ram:
 190
 191 clear_bss:
 192         /*
 193          * Now clear BSS segment
 194          */
 195         move.l  %a0, %a1
 196         add.l   #(_sbss - CONFIG_SYS_MONITOR_BASE),%a1
 197         move.l  %a0, %d1
 198         add.l   #(_ebss - CONFIG_SYS_MONITOR_BASE),%d1
 199 6:
 200         clr.l   (%a1)+
 201         cmp.l   %a1,%d1
 202         bgt.s   6b
 203
 204         /*
 205          * fix got table in RAM
 206          */
 207         move.l  %a0, %a1
 208         add.l   #(__got_start - CONFIG_SYS_MONITOR_BASE),%a1
 209         move.l  %a1,%a5         /* * fix got pointer register a5 */
 210
 211         move.l  %a0, %a2
 212         add.l   #(__got_end - CONFIG_SYS_MONITOR_BASE),%a2
 213
 214 7:
 215         move.l  (%a1),%d1
 216         sub.l   #_start,%d1
 217         add.l   %a0,%d1
 218         move.l  %d1,(%a1)+
 219         cmp.l   %a2, %a1
 220         bne     7b
 221
 222         /* calculate relative jump to board_init_r in ram */
 223         move.l  %a0, %a1
 224         add.l   #(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
 225
 226         /* set parameters for board_init_r */
 227         move.l  %a0,-(%sp)              /* dest_addr */
 228         move.l  %d0,-(%sp)              /* gd */
 229         jsr     (%a1)
 230
 231 /******************************************************************************/
 232
 233 /* exception code */
 234 .globl _fault
 235 _fault:
 236         bra     _fault
 237
 238 .globl _exc_handler
 239 _exc_handler:
 240         SAVE_ALL
 241         movel   %sp,%sp@-
 242         bsr     exc_handler
 243         addql   #4,%sp
 244         RESTORE_ALL
 245
 246 .globl _int_handler
 247 _int_handler:
 248         SAVE_ALL
 249         movel   %sp,%sp@-
 250         bsr     int_handler
 251         addql   #4,%sp
 252         RESTORE_ALL
 253
 254 /******************************************************************************/
 255
 256 .globl version_string
 257 version_string:
 258 .ascii U_BOOT_VERSION_STRING, "\0"
 259 .align 4