[457b6ae] | 1 | /* entry.s |
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| 2 | * |
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| 3 | * This file contains the entry point for the application. |
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| 4 | * The name of this entry point is compiler dependent. |
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| 5 | * It jumps to the BSP which is responsible for performing |
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| 6 | * all initialization. |
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| 7 | * |
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| 8 | * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994. |
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| 9 | * On-Line Applications Research Corporation (OAR). |
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| 10 | * All rights assigned to U.S. Government, 1994. |
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| 11 | * |
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| 12 | * This material may be reproduced by or for the U.S. Government pursuant |
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| 13 | * to the copyright license under the clause at DFARS 252.227-7013. This |
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| 14 | * notice must appear in all copies of this file and its derivatives. |
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| 15 | * |
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| 16 | * Based on the `gen68302' board support package, and covered by the |
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| 17 | * original distribution terms. |
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| 18 | * |
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| 19 | * W. Eric Norum |
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| 20 | * Saskatchewan Accelerator Laboratory |
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| 21 | * University of Saskatchewan |
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| 22 | * Saskatoon, Saskatchewan, CANADA |
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| 23 | * eric@skatter.usask.ca |
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| 24 | * |
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| 25 | * $Id$ |
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| 26 | */ |
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| 27 | |
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| 28 | #include "asm.h" |
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| 29 | |
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| 30 | BEGIN_CODE |
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| 31 | /* |
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| 32 | * Step 1: Decide on Reset Stack Pointer and Initial Program Counter |
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| 33 | */ |
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| 34 | Entry: |
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| 35 | .long SYM(m360)+1024 | 0: Initial SSP |
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| 36 | .long start | 1: Initial PC |
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| 37 | .long uhoh | 2: Bus error |
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| 38 | .long uhoh | 3: Address error |
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| 39 | .long uhoh | 4: Illegal instruction |
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| 40 | .long uhoh | 5: Zero division |
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| 41 | .long uhoh | 6: CHK, CHK2 instruction |
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| 42 | .long uhoh | 7: TRAPcc, TRAPV instructions |
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| 43 | .long uhoh | 8: Privilege violation |
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| 44 | .long uhoh | 9: Trace |
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| 45 | .long uhoh | 10: Line 1010 emulator |
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| 46 | .long uhoh | 11: Line 1111 emulator |
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| 47 | .long uhoh | 12: Hardware breakpoint |
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| 48 | .long uhoh | 13: Reserved for coprocessor violation |
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| 49 | .long uhoh | 14: Format error |
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| 50 | .long uhoh | 15: Uninitialized interrupt |
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| 51 | .long uhoh | 16: Unassigned, reserved |
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| 52 | .long uhoh | 17: |
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| 53 | .long uhoh | 18: |
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| 54 | .long uhoh | 19: |
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| 55 | .long uhoh | 20: |
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| 56 | .long uhoh | 21: |
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| 57 | .long uhoh | 22: |
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| 58 | .long uhoh | 23: |
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| 59 | .long uhoh | 24: Spurious interrupt |
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| 60 | .long uhoh | 25: Level 1 interrupt autovector |
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| 61 | .long uhoh | 26: Level 2 interrupt autovector |
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| 62 | .long uhoh | 27: Level 3 interrupt autovector |
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| 63 | .long uhoh | 28: Level 4 interrupt autovector |
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| 64 | .long uhoh | 29: Level 5 interrupt autovector |
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| 65 | .long uhoh | 30: Level 6 interrupt autovector |
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| 66 | .long uhoh | 31: Level 7 interrupt autovector |
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| 67 | .long uhoh | 32: Trap instruction (0-15) |
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| 68 | .long uhoh | 33: |
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| 69 | .long uhoh | 34: |
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| 70 | .long uhoh | 35: |
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| 71 | .long uhoh | 36: |
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| 72 | .long uhoh | 37: |
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| 73 | .long uhoh | 38: |
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| 74 | .long uhoh | 39: |
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| 75 | .long uhoh | 40: |
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| 76 | .long uhoh | 41: |
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| 77 | .long uhoh | 42: |
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| 78 | .long uhoh | 43: |
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| 79 | .long uhoh | 44: |
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| 80 | .long uhoh | 45: |
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| 81 | .long uhoh | 46: |
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| 82 | .long uhoh | 47: |
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| 83 | .long uhoh | 48: Reserved for coprocessor |
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| 84 | .long uhoh | 49: |
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| 85 | .long uhoh | 50: |
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| 86 | .long uhoh | 51: |
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| 87 | .long uhoh | 52: |
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| 88 | .long uhoh | 53: |
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| 89 | .long uhoh | 54: |
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| 90 | .long uhoh | 55: |
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| 91 | .long uhoh | 56: |
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| 92 | .long uhoh | 57: |
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| 93 | .long uhoh | 58: |
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| 94 | .long uhoh | 59: Unassigned, reserved |
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| 95 | .long uhoh | 60: |
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| 96 | .long uhoh | 61: |
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| 97 | .long uhoh | 62: |
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| 98 | .long uhoh | 63: |
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| 99 | .long uhoh | 64: User defined vectors (192) |
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| 100 | .long uhoh | 65: |
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| 101 | .long uhoh | 66: |
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| 102 | .long uhoh | 67: |
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| 103 | .long uhoh | 68: |
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| 104 | .long uhoh | 69: |
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| 105 | .long uhoh | 70: |
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| 106 | .long uhoh | 71: |
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| 107 | .long uhoh | 72: |
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| 108 | .long uhoh | 73: |
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| 109 | .long uhoh | 74: |
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| 110 | .long uhoh | 75: |
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| 111 | .long uhoh | 76: |
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| 112 | .long uhoh | 77: |
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| 113 | .long uhoh | 78: |
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| 114 | .long uhoh | 79: |
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| 115 | .long uhoh | 80: |
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| 116 | .long uhoh | 81: |
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| 117 | .long uhoh | 82: |
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| 118 | .long uhoh | 83: |
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| 119 | .long uhoh | 84: |
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| 120 | .long uhoh | 85: |
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| 121 | .long uhoh | 86: |
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| 122 | .long uhoh | 87: |
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| 123 | .long uhoh | 88: |
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| 124 | .long uhoh | 89: |
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| 125 | .long uhoh | 90: |
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| 126 | .long uhoh | 91: |
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| 127 | .long uhoh | 92: |
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| 128 | .long uhoh | 93: |
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| 129 | .long uhoh | 94: |
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| 130 | .long uhoh | 95: |
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| 131 | .long uhoh | 96: |
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| 132 | .long uhoh | 97: |
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| 133 | .long uhoh | 98: |
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| 134 | .long uhoh | 99: |
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| 135 | .long uhoh | 100: |
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| 136 | .long uhoh | 101: |
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| 137 | .long uhoh | 102: |
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| 138 | .long uhoh | 103: |
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| 139 | .long uhoh | 104: |
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| 140 | .long uhoh | 105: |
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| 141 | .long uhoh | 106: |
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| 142 | .long uhoh | 107: |
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| 143 | .long uhoh | 108: |
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| 144 | .long uhoh | 109: |
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| 145 | .long uhoh | 110: |
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| 146 | .long uhoh | 111: |
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| 147 | .long uhoh | 112: |
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| 148 | .long uhoh | 113: |
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| 149 | .long uhoh | 114: |
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| 150 | .long uhoh | 115: |
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| 151 | .long uhoh | 116: |
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| 152 | .long uhoh | 117: |
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| 153 | .long uhoh | 118: |
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| 154 | .long uhoh | 119: |
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| 155 | .long uhoh | 120: |
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| 156 | .long uhoh | 121: |
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| 157 | .long uhoh | 122: |
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| 158 | .long uhoh | 123: |
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| 159 | .long uhoh | 124: |
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| 160 | .long uhoh | 125: |
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| 161 | .long uhoh | 126: |
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| 162 | .long uhoh | 127: |
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| 163 | .long uhoh | 128: |
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| 164 | .long uhoh | 129: |
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| 165 | .long uhoh | 130: |
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| 166 | .long uhoh | 131: |
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| 167 | .long uhoh | 132: |
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| 168 | .long uhoh | 133: |
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| 169 | .long uhoh | 134: |
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| 170 | .long uhoh | 135: |
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| 171 | .long uhoh | 136: |
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| 172 | .long uhoh | 137: |
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| 173 | .long uhoh | 138: |
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| 174 | .long uhoh | 139: |
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| 175 | .long uhoh | 140: |
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| 176 | .long uhoh | 141: |
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| 177 | .long uhoh | 142: |
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| 178 | .long uhoh | 143: |
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| 179 | .long uhoh | 144: |
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| 180 | .long uhoh | 145: |
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| 181 | .long uhoh | 146: |
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| 182 | .long uhoh | 147: |
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| 183 | .long uhoh | 148: |
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| 184 | .long uhoh | 149: |
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| 185 | .long uhoh | 150: |
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| 186 | .long uhoh | 151: |
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| 187 | .long uhoh | 152: |
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| 188 | .long uhoh | 153: |
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| 189 | .long uhoh | 154: |
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| 190 | .long uhoh | 155: |
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| 191 | .long uhoh | 156: |
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| 192 | .long uhoh | 157: |
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| 193 | .long uhoh | 158: |
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| 194 | .long uhoh | 159: |
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| 195 | .long uhoh | 160: |
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| 196 | .long uhoh | 161: |
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| 197 | .long uhoh | 162: |
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| 198 | .long uhoh | 163: |
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| 199 | .long uhoh | 164: |
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| 200 | .long uhoh | 165: |
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| 201 | .long uhoh | 166: |
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| 202 | .long uhoh | 167: |
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| 203 | .long uhoh | 168: |
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| 204 | .long uhoh | 169: |
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| 205 | .long uhoh | 170: |
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| 206 | .long uhoh | 171: |
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| 207 | .long uhoh | 172: |
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| 208 | .long uhoh | 173: |
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| 209 | .long uhoh | 174: |
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| 210 | .long uhoh | 175: |
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| 211 | .long uhoh | 176: |
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| 212 | .long uhoh | 177: |
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| 213 | .long uhoh | 178: |
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| 214 | .long uhoh | 179: |
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| 215 | .long uhoh | 180: |
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| 216 | .long uhoh | 181: |
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| 217 | .long uhoh | 182: |
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| 218 | .long uhoh | 183: |
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| 219 | .long uhoh | 184: |
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| 220 | .long uhoh | 185: |
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| 221 | .long uhoh | 186: |
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| 222 | .long uhoh | 187: |
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| 223 | .long uhoh | 188: |
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| 224 | .long uhoh | 189: |
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| 225 | .long uhoh | 190: |
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| 226 | .long uhoh | 191: |
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| 227 | .long uhoh | 192: |
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| 228 | .long uhoh | 193: |
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| 229 | .long uhoh | 194: |
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| 230 | .long uhoh | 195: |
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| 231 | .long uhoh | 196: |
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| 232 | .long uhoh | 197: |
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| 233 | .long uhoh | 198: |
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| 234 | .long uhoh | 199: |
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| 235 | .long uhoh | 200: |
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| 236 | .long uhoh | 201: |
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| 237 | .long uhoh | 202: |
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| 238 | .long uhoh | 203: |
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| 239 | .long uhoh | 204: |
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| 240 | .long uhoh | 205: |
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| 241 | .long uhoh | 206: |
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| 242 | .long uhoh | 207: |
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| 243 | .long uhoh | 208: |
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| 244 | .long uhoh | 209: |
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| 245 | .long uhoh | 210: |
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| 246 | .long uhoh | 211: |
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| 247 | .long uhoh | 212: |
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| 248 | .long uhoh | 213: |
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| 249 | .long uhoh | 214: |
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| 250 | .long uhoh | 215: |
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| 251 | .long uhoh | 216: |
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| 252 | .long uhoh | 217: |
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| 253 | .long uhoh | 218: |
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| 254 | .long uhoh | 219: |
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| 255 | .long uhoh | 220: |
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| 256 | .long uhoh | 221: |
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| 257 | .long uhoh | 222: |
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| 258 | .long uhoh | 223: |
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| 259 | .long uhoh | 224: |
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| 260 | .long uhoh | 225: |
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| 261 | .long uhoh | 226: |
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| 262 | .long uhoh | 227: |
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| 263 | .long uhoh | 228: |
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| 264 | .long uhoh | 229: |
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| 265 | .long uhoh | 230: |
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| 266 | .long uhoh | 231: |
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| 267 | .long uhoh | 232: |
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| 268 | .long uhoh | 233: |
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| 269 | .long uhoh | 234: |
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| 270 | .long uhoh | 235: |
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| 271 | .long uhoh | 236: |
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| 272 | .long uhoh | 237: |
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| 273 | .long uhoh | 238: |
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| 274 | .long uhoh | 239: |
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| 275 | .long uhoh | 240: |
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| 276 | .long uhoh | 241: |
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| 277 | .long uhoh | 242: |
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| 278 | .long uhoh | 243: |
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| 279 | .long uhoh | 244: |
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| 280 | .long uhoh | 245: |
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| 281 | .long uhoh | 246: |
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| 282 | .long uhoh | 247: |
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| 283 | .long uhoh | 248: |
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| 284 | .long uhoh | 249: |
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| 285 | .long uhoh | 250: |
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| 286 | .long uhoh | 251: |
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| 287 | .long uhoh | 252: |
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| 288 | .long uhoh | 253: |
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| 289 | .long uhoh | 254: |
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| 290 | .long uhoh | 255: |
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| 291 | |
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| 292 | /* |
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| 293 | * Default trap handler |
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| 294 | * With an oscilloscope you can see AS* stop |
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| 295 | */ |
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| 296 | uhoh: nop | Leave spot for breakpoint |
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| 297 | stop #0x2700 | Stop with interrupts disabled |
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[487a7ca] | 298 | bra.s uhoh | Stuck forever |
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[457b6ae] | 299 | |
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| 300 | /* |
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[996a9cb4] | 301 | * Place the low-order 3 octets of the board's ethernet address at |
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| 302 | * a `well-known' fixed location relative to the beginning of ROM. |
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[457b6ae] | 303 | */ |
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| 304 | .align 2 |
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[996a9cb4] | 305 | .long ETHERNET_ADDRESS | Low-order 3 octets of ethernet address |
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[457b6ae] | 306 | |
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| 307 | /* |
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| 308 | * Initial PC |
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| 309 | */ |
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[3bc409c] | 310 | .global start |
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[457b6ae] | 311 | start: |
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| 312 | /* |
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| 313 | * Step 2: Stay in Supervisor Mode |
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| 314 | * (i.e. just do nothing for this step) |
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| 315 | */ |
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| 316 | |
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| 317 | /* |
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| 318 | * Step 3: Write the VBR |
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| 319 | */ |
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| 320 | lea Entry,a0 | Get base of vector table |
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[487a7ca] | 321 | movec a0,vbr | Set up the VBR |
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[457b6ae] | 322 | |
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| 323 | /* |
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| 324 | * Step 4: Write the MBAR |
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| 325 | */ |
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[487a7ca] | 326 | movec dfc,d1 | Save destination register |
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[457b6ae] | 327 | moveq #7,d0 | CPU-space funcction code |
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[487a7ca] | 328 | movec d0,dfc | Set destination function code register |
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[457b6ae] | 329 | movel #SYM(m360)+0x101,d0 | MBAR value (mask CPU space accesses) |
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| 330 | movesl d0,0x3FF00 | Set MBAR |
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[487a7ca] | 331 | movec d1,dfc | Restore destination register |
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[457b6ae] | 332 | |
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| 333 | /* |
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| 334 | * Step 5: Verify a dual-port RAM location |
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| 335 | */ |
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| 336 | lea SYM(m360),a0 | Point a0 to first DPRAM location |
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| 337 | moveb #0x33,d0 | Set the test value |
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| 338 | moveb d0,a0@ | Set the memory location |
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| 339 | cmpb a0@,d0 | Does it read back? |
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| 340 | bne uhoh | If not, bad news! |
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| 341 | notb d0 | Flip bits |
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| 342 | moveb d0,a0@ | Set the memory location |
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| 343 | cmpb a0@,d0 | Does it read back? |
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| 344 | bne uhoh | If not, bad news! |
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| 345 | |
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| 346 | /* |
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| 347 | * Remaining steps are handled by C code |
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| 348 | */ |
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| 349 | jmp SYM(_Init68360) | Start C code (which never returns) |
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| 350 | |
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| 351 | /* |
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[996a9cb4] | 352 | * Copy DATA segment, clear BSS segment, set up real stack, |
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| 353 | * initialize heap, start C program. |
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| 354 | * Assume that DATA and BSS sizes are multiples of 4. |
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[457b6ae] | 355 | */ |
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[996a9cb4] | 356 | PUBLIC (_CopyDataClearBSSAndStart) |
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| 357 | SYM(_CopyDataClearBSSAndStart): |
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| 358 | lea copy_start,a0 | Get start of DATA in RAM |
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| 359 | lea SYM(etext),a2 | Get start of DATA in ROM |
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| 360 | cmpl a0,a2 | Are they the same? |
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| 361 | beq.s NOCOPY | Yes, no copy necessary |
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| 362 | lea copy_end,a1 | Get end of DATA in RAM |
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| 363 | bra.s COPYLOOPTEST | Branch into copy loop |
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| 364 | COPYLOOP: |
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| 365 | movel a2@+,a0@+ | Copy word from ROM to RAM |
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| 366 | COPYLOOPTEST: |
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| 367 | cmpl a1,a0 | Done? |
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| 368 | bcs.s COPYLOOP | No, skip |
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| 369 | NOCOPY: |
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| 370 | |
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| 371 | lea clear_start,a0 | Get start of BSS |
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| 372 | lea clear_end,a1 | Get end of BSS |
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| 373 | clrl d0 | Value to set |
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| 374 | bra.s ZEROLOOPTEST | Branch into clear loop |
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[457b6ae] | 375 | ZEROLOOP: |
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[996a9cb4] | 376 | movel d0,a0@+ | Clear a word |
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[457b6ae] | 377 | ZEROLOOPTEST: |
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[996a9cb4] | 378 | cmpl a1,a0 | Done? |
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| 379 | bcs.s ZEROLOOP | No, skip |
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| 380 | |
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[457b6ae] | 381 | movel #stack_init,a7 | set master stack pointer |
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| 382 | movel d0,a7@- | environp |
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| 383 | movel d0,a7@- | argv |
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| 384 | movel d0,a7@- | argc |
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| 385 | jsr SYM(main) | Call C main |
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| 386 | |
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| 387 | | Should this just force a reset? |
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| 388 | mainDone: nop | Leave spot for breakpoint |
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| 389 | stop #0x2700 | Stop with interrupts disabled |
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[487a7ca] | 390 | bra.s mainDone | Stuck forever |
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[457b6ae] | 391 | |
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| 392 | .align 2 |
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| 393 | PUBLIC (_HeapSize) |
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| 394 | SYM (_HeapSize): |
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| 395 | .long HeapSize |
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| 396 | PUBLIC (_StackSize) |
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| 397 | SYM (_StackSize): |
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| 398 | .long StackSize |
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| 399 | END_CODE |
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| 400 | |
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| 401 | BEGIN_BSS |
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| 402 | .align 2 |
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| 403 | PUBLIC (environ) |
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| 404 | SYM (environ): |
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| 405 | .long 0 |
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| 406 | END |
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