aplfw/sample/arm/ez_arm7/gcc/crt0.S

   1 /* ------------------------------------------------------------------------ */
   2 /*  Hyper Operating System V4 Advance                                       */
   3 /*    Sample program for ADuC7000 series                                    */
   4 /*                                                                          */
   5 /*                                  Copyright (C) 1998-2007 by Project HOS  */
   6 /*                                  http://sourceforge.jp/projects/hos/     */
   7 /* ------------------------------------------------------------------------ */
   8
   9
  10                                 .extern         __kernel_int_isp
  11                                 .extern         ___data
  12                                 .extern         ___data_end
  13                                 .extern         ___bss
  14                                 .extern         ___bss_end
  15                                 .extern         main
  16
  17                                 .global         _reset_handler
  18                                 .global         __main
  19
  20
  21                                 .text
  22
  23 #define Mode_USR                0x10
  24 #define Mode_IRQ                0x12
  25 #define Mode_FIQ                0x11
  26 #define Mode_SVC                0x13
  27 #define Mode_UND                0x1b
  28 #define Mode_SYS                0x1f
  29 #define I_Bit                   0x80
  30 #define F_Bit                   0x40
  31 #define T_Bit                   0x20
  32
  33
  34 /************************************************
  35   リセットハンドラ
  36 ************************************************/
  37                                 .align          4
  38 _reset_handler:
  39                                 /* モード設定 */
  40                                 msr             cpsr_c, #(Mode_SYS | F_Bit | I_Bit)
  41
  42                                 /* スタック仮設定 */
  43                                 ldr             r0, =_kernel_int_isp
  44                                 ldr     sp, [r0]
  45
  46
  47                                 /* DATA領域のコピー */
  48                                 ldr             r0, =___data_rom
  49                                 ldr             r1, =___data
  50                                 ldr             r2, =___data_end
  51 data_loop:
  52                                 cmp             r1, r2
  53                                 ldrcc   r3, [r0], #4
  54                                 strcc   r3, [r1], #4
  55                                 bcc             data_loop
  56
  57
  58                                 /* BSS領域の初期化 */
  59                                 ldr             r0, =___bss
  60                                 ldr             r1, =___bss_end
  61                                 mov             r2, #0
  62 bss_loop:
  63                                 cmp             r0, r1
  64                                 strcc   r2, [r0], #4
  65                                 bcc             bss_loop
  66
  67
  68                                 /* main関数の呼び出し */
  69                                 bl              main
  70 end_loop:
  71                                 b               end_loop
  72
  73
  74 __main:
  75                                 bx              lr
  76
  77
  78
  79                                 .end
  80
  81
  82 /* end of file */