root/platform/ixus860_sd870/sub/100c/boot.c

DEFINITIONS

1. CreateTask_spytask
2. taskCreateHook
3. boot
4. sub_FF8101A4_my
5. sub_FF810FB8_my
6. uHwSetup_my
7. CreateTask_Startup_my
8. task_Startup_my
9. taskcreatePhySw_my
10. init_file_modules_task
11. sub_FF869D2C_my
12. sub_FF84D4A8_my
13. sub_FF84D2E4_my
14. sub_FF84D17C_my
15. my_touchw_task

   1 /*
   2  * boot.c - auto-generated by CHDK code_gen.
   3  */
   4 #include "lolevel.h"
   5 #include "platform.h"
   6 #include "core.h"
   8 const char * const new_sa = &_end;
  10 /*----------------------------------------------------------------------
  11     CreateTask_spytask
  12 -----------------------------------------------------------------------*/
  13 void CreateTask_spytask() {
_CreateTask("SpyTask", 0x19, 0x2000, core_spytask, 0);
  15 };
  18 void my_touchw_task(void);
  20 void taskCreateHook(int *p) {
p-=16;
  22     if (p[0]==(int)0xff85bd10)  p[0]=(int)capt_seq_task;
  23     if (p[0]==(int)0xff8aebf4)  p[0]=(int)exp_drv_task;
  24     if (p[0]==(int)0xff85821c)  p[0]=(int)movie_record_task;
  25     if (p[0]==(int)0xffa021bc)  p[0]=(int)filewritetask;
  26     if (p[0]==(int)0xff870ce8)  p[0]=(int)init_file_modules_task;
  27     if (p[0]==(int)0xff8e6dc0)  p[0]=(int)my_touchw_task;
  28 }
  30 void boot()
  31 {
  32     long *canon_data_src = (void*)0xFFAF47EC;
  33     long *canon_data_dst = (void*)0x1900;
  34     long canon_data_len = 0xFEBC - 0x1900; // data_end - data_start
  35     long *canon_bss_start = (void*)0xFEBC; // just after data 
  36     long canon_bss_len = 0x9FE50 - 0xFEBC; 
  38     long i;
  41     // Enable CPU caches and MPU
  42     asm volatile (
  43     "MRC     p15, 0, R0,c1,c0\n"
  44     "ORR     R0, R0, #0x1000\n"
  45     "ORR     R0, R0, #4\n"
  46     "ORR     R0, R0, #1\n"
  47     "MCR     p15, 0, R0,c1,c0\n"
  48     :::"r0");
  50     for(i=0;i<canon_data_len/4;i++)
canon_data_dst[i]=canon_data_src[i];
  53     for(i=0;i<canon_bss_len/4;i++)
canon_bss_start[i]=0;
  56     // jump to init-sequence that follows the data-copy-routine
  57     asm volatile ("B      sub_FF8101A4_my\n");
  58 };
  61 /*************************************************************/
  62 //** sub_FF8101A4_my @ 0xFF8101A4 - 0xFF81020C, length=27
  63 void __attribute__((naked,noinline)) sub_FF8101A4_my() {
  64     //http://chdk.setepontos.com/index.php/topic,4194.0.html
  65     *(int*)0x1930=(int)taskCreateHook;
  67     // replacement of sub_FF843E9C for correct power-on.
  68     //(short press = playback mode, long press = record mode)
  69     *(int*)(0x23E0+0x4)= (*(int*)0xC0220078) & 1 ? 0x100000 : 0x200000;
  71 asm volatile (
  72 "    LDR     R0, =0xFF81021C \n"
  73 "    MOV     R1, #0 \n"
  74 "    LDR     R3, =0xFF810254 \n"
  76 "loc_FF8101B0:\n"
  77 "    CMP     R0, R3 \n"
  78 "    LDRCC   R2, [R0], #4 \n"
  79 "    STRCC   R2, [R1], #4 \n"
  80 "    BCC     loc_FF8101B0 \n"
  81 "    LDR     R0, =0xFF810254 \n"
  82 "    MOV     R1, #0x4B0 \n"
  83 "    LDR     R3, =0xFF810468 \n"
  85 "loc_FF8101CC:\n"
  86 "    CMP     R0, R3 \n"
  87 "    LDRCC   R2, [R0], #4 \n"
  88 "    STRCC   R2, [R1], #4 \n"
  89 "    BCC     loc_FF8101CC \n"
  90 "    MOV     R0, #0xD2 \n"
  91 "    MSR     CPSR_cxsf, R0 \n"
  92 "    MOV     SP, #0x1000 \n"
  93 "    MOV     R0, #0xD3 \n"
  94 "    MSR     CPSR_cxsf, R0 \n"
  95 "    MOV     SP, #0x1000 \n"
  96 "    LDR     R0, =0x6C4 \n"
  97 "    LDR     R2, =0xEEEEEEEE \n"
  98 "    MOV     R3, #0x1000 \n"
 100 "loc_FF810200:\n"
 101 "    CMP     R0, R3 \n"
 102 "    STRCC   R2, [R0], #4 \n"
 103 "    BCC     loc_FF810200 \n"
 104 "    BL      sub_FF810FB8_my \n"  // --> Patched. Old value = 0xFF810FB8.
 105 );
 106 }
 108 /*************************************************************/
 109 //** sub_FF810FB8_my @ 0xFF810FB8 - 0xFF811058, length=41
 110 void __attribute__((naked,noinline)) sub_FF810FB8_my() {
 111 asm volatile (
 112 "    STR     LR, [SP, #-4]! \n"
 113 "    SUB     SP, SP, #0x74 \n"
 114 "    MOV     R0, SP \n"
 115 "    MOV     R1, #0x74 \n"
 116 "    BL      sub_FFA8C05C \n"
 117 "    MOV     R0, #0x53000 \n"
 118 "    STR     R0, [SP, #4] \n"
 120 #if defined(CHDK_NOT_IN_CANON_HEAP) // use original heap offset if CHDK is loaded in high memory
 121 "    LDR     R0, =0x9FE50 \n"
 122 #else
 123 "    LDR     R0, =new_sa\n"   // otherwise use patched value
 124 "    LDR     R0, [R0]\n"      //
 125 #endif
 127 "    LDR     R2, =0x2ABC00 \n"
 128 "    LDR     R1, =0x2A4968 \n"
 129 "    STR     R0, [SP, #8] \n"
 130 "    SUB     R0, R1, R0 \n"
 131 "    ADD     R3, SP, #0xC \n"
 132 "    STR     R2, [SP] \n"
 133 "    STMIA   R3, {R0-R2} \n"
 134 "    MOV     R0, #0x22 \n"
 135 "    STR     R0, [SP, #0x18] \n"
 136 "    MOV     R0, #0x68 \n"
 137 "    STR     R0, [SP, #0x1C] \n"
 138 "    LDR     R0, =0x19B \n"
 139 "    MOV     R1, #0x64 \n"
 140 "    STRD    R0, [SP, #0x20] \n"
 141 "    MOV     R0, #0x78 \n"
 142 "    STRD    R0, [SP, #0x28] \n"
 143 "    MOV     R0, #0 \n"
 144 "    STR     R0, [SP, #0x30] \n"
 145 "    STR     R0, [SP, #0x34] \n"
 146 "    MOV     R0, #0x10 \n"
 147 "    STR     R0, [SP, #0x5C] \n"
 148 "    MOV     R0, #0x800 \n"
 149 "    STR     R0, [SP, #0x60] \n"
 150 "    MOV     R0, #0xA0 \n"
 151 "    STR     R0, [SP, #0x64] \n"
 152 "    MOV     R0, #0x280 \n"
 153 "    STR     R0, [SP, #0x68] \n"
 154 "    LDR     R1, =uHwSetup_my \n"  // --> Patched. Old value = 0xFF814DBC.
 155 "    MOV     R0, SP \n"
 156 "    MOV     R2, #0 \n"
 157 "    BL      sub_FF812D70 \n"
 158 "    ADD     SP, SP, #0x74 \n"
 159 "    LDR     PC, [SP], #4 \n"
 160 );
 161 }
 163 /*************************************************************/
 164 //** uHwSetup_my @ 0xFF814DBC - 0xFF814E30, length=30
 165 void __attribute__((naked,noinline)) uHwSetup_my() {
 166 asm volatile (
 167 "    STMFD   SP!, {R4,LR} \n"
 168 "    BL      sub_FF81095C \n"
 169 "    BL      sub_FF819A10 \n"
 170 "    CMP     R0, #0 \n"
 171 "    LDRLT   R0, =0xFF814ED0 /*'dmSetup'*/ \n"
 172 "    BLLT    _err_init_task \n"
 173 "    BL      sub_FF8149E0 \n"
 174 "    CMP     R0, #0 \n"
 175 "    LDRLT   R0, =0xFF814ED8 /*'termDriverInit'*/ \n"
 176 "    BLLT    _err_init_task \n"
 177 "    LDR     R0, =0xFF814EE8 /*'/_term'*/ \n"
 178 "    BL      sub_FF814ACC \n"
 179 "    CMP     R0, #0 \n"
 180 "    LDRLT   R0, =0xFF814EF0 /*'termDeviceCreate'*/ \n"
 181 "    BLLT    _err_init_task \n"
 182 "    LDR     R0, =0xFF814EE8 /*'/_term'*/ \n"
 183 "    BL      sub_FF81357C \n"
 184 "    CMP     R0, #0 \n"
 185 "    LDRLT   R0, =0xFF814F04 /*'stdioSetup'*/ \n"
 186 "    BLLT    _err_init_task \n"
 187 "    BL      sub_FF819598 \n"
 188 "    CMP     R0, #0 \n"
 189 "    LDRLT   R0, =0xFF814F10 /*'stdlibSetup'*/ \n"
 190 "    BLLT    _err_init_task \n"
 191 "    BL      sub_FF8114D0 \n"
 192 "    CMP     R0, #0 \n"
 193 "    LDRLT   R0, =0xFF814F1C /*'armlib_setup'*/ \n"
 194 "    BLLT    _err_init_task \n"
 195 "    LDMFD   SP!, {R4,LR} \n"
 196 "    B       CreateTask_Startup_my \n"  // --> Patched. Old value = 0xFF81DCD4.
 197 );
 198 }
 200 /*************************************************************/
 201 //** CreateTask_Startup_my @ 0xFF81DCD4 - 0xFF81DD48, length=30
 202 void __attribute__((naked,noinline)) CreateTask_Startup_my() {
 203 asm volatile (
 204 "    STMFD   SP!, {R3,LR} \n"
 205 "    BL      sub_FF843E74 \n"
 206 "    BL      sub_FF82BA7C \n"
 207 "    CMP     R0, #0 \n"
 208 "    BNE     loc_FF81DD0C \n"
 209 "    LDR     R2, =0xC0220000 \n"
 210 "    LDR     R0, [R2, #0x78] \n"
 211 "    LDR     R1, [R2, #0x7C] \n"
 212 "    AND     R0, R0, R1 \n"
 213 "    TST     R0, #1 \n"
 214 "    BEQ     loc_FF81DD0C \n"
 215 "    MOV     R0, #0x44 \n"
 216 "    STR     R0, [R2, #0x4C] \n"
 218 "loc_FF81DD08:\n"
 219 "    B       loc_FF81DD08 \n"
 221 "loc_FF81DD0C:\n"
 222 //"  BL      _sub_FF843E9C \n"  // Removed for correct power-on
 223 "    BL      sub_FF843E88 \n"
 224 "    BL      sub_FF829608 \n"
 225 "    MOV     R1, #0x300000 \n"
 226 "    MOV     R0, #0 \n"
 227 "    BL      sub_FF829850 \n"
 228 "    BL      sub_FF8297FC /*_EnableDispatch*/ \n"
 229 "    MOV     R3, #0 \n"
 230 "    STR     R3, [SP] \n"
 231 "    LDR     R3, =task_Startup_my \n"  // --> Patched. Old value = 0xFF81DC78.
 232 "    MOV     R2, #0 \n"
 233 "    MOV     R1, #0x19 \n"
 234 "    LDR     R0, =0xFF81DD50 /*'Startup'*/ \n"
 235 "    BL      _CreateTask \n"
 236 "    MOV     R0, #0 \n"
 237 "    LDMFD   SP!, {R12,PC} \n"
 238 );
 239 }
 241 /*************************************************************/
 242 //** task_Startup_my @ 0xFF81DC78 - 0xFF81DCD0, length=23
 243 void __attribute__((naked,noinline)) task_Startup_my() {
 244 asm volatile (
 245 "    STMFD   SP!, {R4,LR} \n"
 246 "    BL      _taskcreate_ClockSave \n"
 247 "    BL      sub_FF823FA8 \n"
 248 "    BL      sub_FF820E84 \n"
 249 //"  BL      _sub_FF8444A8 \n"  // --> Nullsub call removed.
 250 "    BL      sub_FF82BC5C \n"
 251 //"  BL      _StartDiskboot \n"  // load DISKBOOT.BIN
 252 "    BL      CreateTask_spytask\n" // added
 253 "    BL      sub_FF86D26C \n"
 254 "    BL      sub_FF82BCAC \n"
 255 "    BL      sub_FF828B4C \n"
 256 "    BL      sub_FF82BE28 \n"
 257 "    BL      taskcreatePhySw_my \n"  // --> Patched. Old value = _taskcreate_PhySw. Checks buttons and acts accordingly
 258 "    BL      sub_FF825C34 \n"
 259 "    BL      sub_FF82BE40 \n"
 260 "    BL      _nullsub_2 \n"
 261 "    BL      sub_FF82213C \n"
 262 "    BL      _taskcreate_Bye \n"
 263 "    BL      sub_FF8228D8 \n"
 264 "    BL      _taskcreate_TempCheck \n"
 265 "    BL      sub_FF82C8E4 \n"
 266 "    BL      sub_FF822004 \n"
 267 "    LDMFD   SP!, {R4,LR} \n"
 268 "    B       sub_FF815088 \n"
 269 );
 270 }
 272 /*************************************************************/
 273 //** taskcreatePhySw_my @ 0xFF822DAC - 0xFF822DE0, length=14
 274 void __attribute__((naked,noinline)) taskcreatePhySw_my() {
 275 asm volatile (
 276 "    STMFD   SP!, {R3-R5,LR} \n"
 277 "    LDR     R4, =0x1C98 \n"
 278 "    LDR     R0, [R4, #0x10] \n"
 279 "    CMP     R0, #0 \n"
 280 "    BNE     loc_FF822DE0 \n"
 281 "    MOV     R3, #0 \n"
 282 "    STR     R3, [SP] \n"
 283 "    LDR     R3, =mykbd_task \n"  // --> Patched. Old value = 0xFF822D78.
 284 "    MOV     R2, #0x2000 \n"  // --> Patched. Old value = 0x800. stack size for new task_PhySw so we don't have to do stack switch
 285 "    MOV     R1, #0x17 \n"
 286 "    LDR     R0, =0xFF822FA0 /*'PhySw'*/ \n"
 287 "    BL      _KernelCreateTask \n"
 288 "    STR     R0, [R4, #0x10] \n"
 290 "loc_FF822DE0:\n"
 291 "    LDMFD   SP!, {R3-R5,PC} \n"
 292 );
 293 }
 295 /*************************************************************/
 296 //** init_file_modules_task @ 0xFF870CE8 - 0xFF870D1C, length=14
 297 void __attribute__((naked,noinline)) init_file_modules_task() {
 298 asm volatile (
 299 "    STMFD   SP!, {R4-R6,LR} \n"
 300 "    BL      sub_FF869D00 \n"
 301 "    LDR     R5, =0x5006 \n"
 302 "    MOVS    R4, R0 \n"
 303 "    MOVNE   R1, #0 \n"
 304 "    MOVNE   R0, R5 \n"
 305 "    BLNE    _PostLogicalEventToUI \n"
 306 "    BL      sub_FF869D2C_my \n"  // --> Patched. Old value = 0xFF869D2C.
 307 "    BL      core_spytask_can_start\n"  // CHDK: Set "it's-safe-to-start" flag for spytask
 308 "    CMP     R4, #0 \n"
 309 "    MOVEQ   R0, R5 \n"
 310 "    LDMEQFD SP!, {R4-R6,LR} \n"
 311 "    MOVEQ   R1, #0 \n"
 312 "    BEQ     _PostLogicalEventToUI \n"
 313 "    LDMFD   SP!, {R4-R6,PC} \n"
 314 );
 315 }
 317 /*************************************************************/
 318 //** sub_FF869D2C_my @ 0xFF869D2C - 0xFF869D64, length=15
 319 void __attribute__((naked,noinline)) sub_FF869D2C_my() {
 320 asm volatile (
 321 "    STMFD   SP!, {R4,LR} \n"
 322 "    BL      sub_FF84D4A8_my \n"  // --> Patched. Old value = 0xFF84D4A8.
 323 "    LDR     R4, =0x58A8 \n"
 324 "    LDR     R0, [R4, #4] \n"
 325 "    CMP     R0, #0 \n"
 326 "    BNE     loc_FF869D5C \n"
 327 "    BL      sub_FF879F20 \n"
 328 "    BL      sub_FF8FB3B0 \n"
 329 "    BL      sub_FF879F20 \n"
 330 "    BL      sub_FF907F04 \n"
 331 "    BL      sub_FF879F30 \n"
 332 "    BL      sub_FF8FB458 \n"
 334 "loc_FF869D5C:\n"
 335 "    MOV     R0, #1 \n"
 336 "    STR     R0, [R4] \n"
 337 "    LDMFD   SP!, {R4,PC} \n"
 338 );
 339 }
 341 /*************************************************************/
 342 //** sub_FF84D4A8_my @ 0xFF84D4A8 - 0xFF84D540, length=39
 343 void __attribute__((naked,noinline)) sub_FF84D4A8_my() {
 344 asm volatile (
 345 "    STMFD   SP!, {R4-R6,LR} \n"
 346 "    MOV     R6, #0 \n"
 347 "    MOV     R0, R6 \n"
 348 "    BL      sub_FF84D078 \n"
 349 "    LDR     R4, =0x125D4 \n"
 350 "    MOV     R5, #0 \n"
 351 "    LDR     R0, [R4, #0x38] \n"
 352 "    BL      sub_FF84DA40 \n"
 353 "    CMP     R0, #0 \n"
 354 "    LDREQ   R0, =0x2B3C \n"
 355 "    STREQ   R5, [R0, #0xC] \n"
 356 "    STREQ   R5, [R0, #0x10] \n"
 357 "    STREQ   R5, [R0, #0x14] \n"
 358 "    MOV     R0, R6 \n"
 359 "    BL      sub_FF84D0B8 \n"
 360 "    MOV     R0, R6 \n"
 361 "    BL      sub_FF84D2E4_my \n"  // --> Patched. Old value = 0xFF84D2E4.
 362 "    MOV     R5, R0 \n"
 363 "    MOV     R0, R6 \n"
 364 "    BL      sub_FF84D350 \n"
 365 "    LDR     R1, [R4, #0x3C] \n"
 366 "    AND     R2, R5, R0 \n"
 367 "    CMP     R1, #0 \n"
 368 "    MOV     R0, #0 \n"
 369 "    MOVEQ   R0, #0x80000001 \n"
 370 "    BEQ     loc_FF84D53C \n"
 371 "    LDR     R3, [R4, #0x2C] \n"
 372 "    CMP     R3, #2 \n"
 373 "    MOVEQ   R0, #4 \n"
 374 "    CMP     R1, #5 \n"
 375 "    ORRNE   R0, R0, #1 \n"
 376 "    BICEQ   R0, R0, #1 \n"
 377 "    CMP     R2, #0 \n"
 378 "    BICEQ   R0, R0, #2 \n"
 379 "    ORREQ   R0, R0, #0x80000000 \n"
 380 "    BICNE   R0, R0, #0x80000000 \n"
 381 "    ORRNE   R0, R0, #2 \n"
 383 "loc_FF84D53C:\n"
 384 "    STR     R0, [R4, #0x40] \n"
 385 "    LDMFD   SP!, {R4-R6,PC} \n"
 386 );
 387 }
 389 /*************************************************************/
 390 //** sub_FF84D2E4_my @ 0xFF84D2E4 - 0xFF84D34C, length=27
 391 void __attribute__((naked,noinline)) sub_FF84D2E4_my() {
 392 asm volatile (
 393 "    STMFD   SP!, {R4-R6,LR} \n"
 394 "    LDR     R5, =0x2B3C \n"
 395 "    MOV     R6, R0 \n"
 396 "    LDR     R0, [R5, #0x10] \n"
 397 "    CMP     R0, #0 \n"
 398 "    MOVNE   R0, #1 \n"
 399 "    LDMNEFD SP!, {R4-R6,PC} \n"
 400 "    MOV     R0, #0x17 \n"
 401 "    MUL     R1, R0, R6 \n"
 402 "    LDR     R0, =0x125D4 \n"
 403 "    ADD     R4, R0, R1, LSL#2 \n"
 404 "    LDR     R0, [R4, #0x38] \n"
 405 "    MOV     R1, R6 \n"
 406 "    BL      sub_FF84D17C_my \n"  // --> Patched. Old value = 0xFF84D17C.
 407 "    CMP     R0, #0 \n"
 408 "    LDMEQFD SP!, {R4-R6,PC} \n"
 409 "    LDR     R0, [R4, #0x38] \n"
 410 "    MOV     R1, R6 \n"
 411 "    BL      sub_FF84DB58 \n"
 412 "    CMP     R0, #0 \n"
 413 "    LDMEQFD SP!, {R4-R6,PC} \n"
 414 "    MOV     R0, R6 \n"
 415 "    BL      sub_FF84CC98 \n"
 416 "    CMP     R0, #0 \n"
 417 "    MOVNE   R1, #1 \n"
 418 "    STRNE   R1, [R5, #0x10] \n"
 419 "    LDMFD   SP!, {R4-R6,PC} \n"
 420 );
 421 }
 423 /*************************************************************/
 424 //** sub_FF84D17C_my @ 0xFF84D17C - 0xFF84D2E0, length=90
 425 void __attribute__((naked,noinline)) sub_FF84D17C_my() {
 426 asm volatile (
 427 "    STMFD   SP!, {R4-R8,LR} \n"
 428 "    MOV     R8, R0 \n"
 429 "    MOV     R0, #0x17 \n"
 430 "    MUL     R1, R0, R1 \n"
 431 "    LDR     R0, =0x125D4 \n"
 432 "    MOV     R6, #0 \n"
 433 "    ADD     R7, R0, R1, LSL#2 \n"
 434 "    LDR     R0, [R7, #0x3C] \n"
 435 "    MOV     R5, #0 \n"
 436 "    CMP     R0, #6 \n"
 437 "    ADDLS   PC, PC, R0, LSL#2 \n"
 438 "    B       loc_FF84D2C8 \n"
 439 "    B       loc_FF84D1E0 \n"
 440 "    B       loc_FF84D1C8 \n"
 441 "    B       loc_FF84D1C8 \n"
 442 "    B       loc_FF84D1C8 \n"
 443 "    B       loc_FF84D1C8 \n"
 444 "    B       loc_FF84D2C0 \n"
 445 "    B       loc_FF84D1C8 \n"
 447 "loc_FF84D1C8:\n"
 448 "    MOV     R2, #0 \n"
 449 "    MOV     R1, #0x200 \n"
 450 "    MOV     R0, #3 \n"
 451 "    BL      _exmem_ualloc \n"
 452 "    MOVS    R4, R0 \n"
 453 "    BNE     loc_FF84D1E8 \n"
 455 "loc_FF84D1E0:\n"
 456 "    MOV     R0, #0 \n"
 457 "    LDMFD   SP!, {R4-R8,PC} \n"
 459 "loc_FF84D1E8:\n"
 460 "    LDR     R12, [R7, #0x4C] \n"
 461 "    MOV     R3, R4 \n"
 462 "    MOV     R2, #1 \n"
 463 "    MOV     R1, #0 \n"
 464 "    MOV     R0, R8 \n"
 465 "    BLX     R12 \n"
 466 "    CMP     R0, #1 \n"
 467 "    BNE     loc_FF84D214 \n"
 468 "    MOV     R0, #3 \n"
 469 "    BL      _exmem_ufree \n"
 470 "    B       loc_FF84D1E0 \n"
 472 "loc_FF84D214:\n"
 473 "    MOV     R0, R8 \n"
 474 "    BL      sub_FF9186B8 \n"
 476 "    MOV     R1, R4\n"              //  pointer to MBR in R1
 477 "    BL      mbr_read_dryos\n"      //  total sectors count in R0 before and after call
 479 // Start of DataGhost's FAT32 autodetection code
 480 // Policy: If there is a partition which has type W95 FAT32, use the first one of those for image storage
 481 // According to the code below, we can use R1, R2, R3 and R12.
 482 // LR wasn't really used anywhere but for storing a part of the partition signature. This is the only thing
 483 // that won't work with an offset, but since we can load from LR+offset into LR, we can use this to do that :)
 484 "    MOV     R12, R4\n"             // Copy the MBR start address so we have something to work with
 485 "    MOV     LR, R4\n"              // Save old offset for MBR signature
 486 "    MOV     R1, #1\n"              // Note the current partition number
 487 "    B       dg_sd_fat32_enter\n"   // We actually need to check the first partition as well, no increments yet!
 488 "dg_sd_fat32:\n"
 489 "    CMP     R1, #4\n"              // Did we already see the 4th partition?
 490 "    BEQ     dg_sd_fat32_end\n"     // Yes, break. We didn't find anything, so don't change anything.
 491 "    ADD     R12, R12, #0x10\n"     // Second partition
 492 "    ADD     R1, R1, #1\n"          // Second partition for the loop
 493 "dg_sd_fat32_enter:\n"
 494 "    LDRB    R2, [R12, #0x1BE]\n"   // Partition status
 495 "    LDRB    R3, [R12, #0x1C2]\n"   // Partition type (FAT32 = 0xB)
 496 "    CMP     R3, #0xB\n"            // Is this a FAT32 partition?
 497 "    CMPNE   R3, #0xC\n"            // Not 0xB, is it 0xC (FAT32 LBA) then?
 498 "    CMPNE   R3, #0x7\n"            // exFat?
 499 "    BNE     dg_sd_fat32\n"         // No, it isn't. Loop again.
 500 "    CMP     R2, #0x00\n"           // It is, check the validity of the partition type
 501 "    CMPNE   R2, #0x80\n"
 502 "    BNE     dg_sd_fat32\n"         // Invalid, go to next partition
 503                                     // This partition is valid, it's the first one, bingo!
 504 "    MOV     R4, R12\n"             // Move the new MBR offset for the partition detection.
 506 "dg_sd_fat32_end:\n"
 507 // End of DataGhost's FAT32 autodetection code
 509 "    LDRB    R1, [R4, #0x1C9] \n"
 510 "    LDRB    R3, [R4, #0x1C8] \n"
 511 "    LDRB    R12, [R4, #0x1CC] \n"
 512 "    MOV     R1, R1, LSL#24 \n"
 513 "    ORR     R1, R1, R3, LSL#16 \n"
 514 "    LDRB    R3, [R4, #0x1C7] \n"
 515 "    LDRB    R2, [R4, #0x1BE] \n"
 516 //"  LDRB    LR, [R4, #0x1FF] \n"
 517 "    ORR     R1, R1, R3, LSL#8 \n"
 518 "    LDRB    R3, [R4, #0x1C6] \n"
 519 "    CMP     R2, #0 \n"
 520 "    CMPNE   R2, #0x80 \n"
 521 "    ORR     R1, R1, R3 \n"
 522 "    LDRB    R3, [R4, #0x1CD] \n"
 523 "    MOV     R3, R3, LSL#24 \n"
 524 "    ORR     R3, R3, R12, LSL#16 \n"
 525 "    LDRB    R12, [R4, #0x1CB] \n"
 526 "    ORR     R3, R3, R12, LSL#8 \n"
 527 "    LDRB    R12, [R4, #0x1CA] \n"
 528 "    ORR     R3, R3, R12 \n"
 529 //"  LDRB    R12, [R4, #0x1FE] \n"  // Replaced, see below
 530 //mod start
 531 "    LDRB    R12, [LR,#0x1FE]\n"           // New! First MBR signature byte (0x55)
 532 "    LDRB    LR, [LR,#0x1FF]\n"            //      Last MBR signature byte (0xAA)
 533 //mod end
 534 "    MOV     R4, #0 \n"
 535 "    BNE     loc_FF84D29C \n"
 536 "    CMP     R0, R1 \n"
 537 "    BCC     loc_FF84D29C \n"
 538 "    ADD     R2, R1, R3 \n"
 539 "    CMP     R2, R0 \n"
 540 "    CMPLS   R12, #0x55 \n"
 541 "    CMPEQ   LR, #0xAA \n"
 542 "    MOVEQ   R6, R1 \n"
 543 "    MOVEQ   R5, R3 \n"
 544 "    MOVEQ   R4, #1 \n"
 546 "loc_FF84D29C:\n"
 547 "    MOV     R0, #3 \n"
 548 "    BL      _exmem_ufree \n"
 549 "    CMP     R4, #0 \n"
 550 "    BNE     loc_FF84D2D4 \n"
 551 "    MOV     R6, #0 \n"
 552 "    MOV     R0, R8 \n"
 553 "    BL      sub_FF9186B8 \n"
 554 "    MOV     R5, R0 \n"
 555 "    B       loc_FF84D2D4 \n"
 557 "loc_FF84D2C0:\n"
 558 "    MOV     R5, #0x40 \n"
 559 "    B       loc_FF84D2D4 \n"
 561 "loc_FF84D2C8:\n"
 562 "    LDR     R1, =0x365 \n"
 563 "    LDR     R0, =0xFF84D170 /*'Mounter.c'*/ \n"
 564 "    BL      _DebugAssert \n"
 566 "loc_FF84D2D4:\n"
 567 "    STR     R6, [R7, #0x44]! \n"
 568 "    MOV     R0, #1 \n"
 569 "    STR     R5, [R7, #4] \n"
 570 "    LDMFD   SP!, {R4-R8,PC} \n"
 571 );
 572 }
 574 /*************************************************************/
 575 //** my_touchw_task @ 0xFF8E6DC0 - 0xFF8E6DF8, length=15
 576 void __attribute__((naked,noinline)) my_touchw_task() {
 577 asm volatile (
 578 "    STMFD   SP!, {R4-R6,LR} \n"
 579 "    BL      sub_FF8E79C4 \n"
 580 "    LDR     R5, =0xFFAA0D8C \n"
 581 "    LDR     R4, =0x9C10 \n"
 583 "loc_FF8E6DD0:\n"
 584 "    LDR     R0, [R4, #0x1C] \n"
 585 "    MOV     R3, #0x1D0 \n"
 586 "    LDR     R2, =0xFF8E6FE0 /*'TouchWheel.c'*/ \n"
 587 "    MOV     R1, #0 \n"
 588 "    BL      sub_FF81BF78 /*_TakeSemaphoreStrictly*/ \n"
 589 "     BL      kbd_is_blocked\n"
 590 "     MOV     R6, R0\n"
 591 "    LDR     R0, [R4, #0x24] \n"
 592 "    LDR     R1, [R4, #0x28] \n"
 594 // if not blocked, use original
 595 "     CMP     R6, #0\n"
 596 "     BEQ     bypass_skip_touch\n"
 598 // if kbd is blocked, skip touch events
 599 "     CMP     R0, #2\n"
 600 "     CMPEQ   R1, #1\n"
 601 "     BEQ     loc_FF8E6DD0\n"
 603 "bypass_skip_touch:\n"
 605 "    ADD     R0, R5, R0, LSL#4 \n"
 606 "    LDR     R0, [R0, R1, LSL#2] \n"
 607 "    BLX     R0 \n"
 608 "    B       loc_FF8E6DD0 \n"
 609 );
 610 }