reactos/boot/freeldr/bootsect/ofwboot.s

   1         .section .text
   2 _start:
   3         .long   0xe00000 + 12
   4         .long   0
   5         .long   0
   6
   7 /*
   8  * LIFTED FROM arch/macppc/stand/ofwboot/Locore.c
   9  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
  10  * Copyright (C) 1995, 1996 TooLs GmbH.
  11  * All rights reserved.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions and the following disclaimer.
  18  * 2. Redistributions in binary form must reproduce the above copyright
  19  *    notice, this list of conditions and the following disclaimer in the
  20  *    documentation and/or other materials provided with the distribution.
  21  * 3. All advertising materials mentioning features or use of this software
  22  *    must display the following acknowledgement:
  23  *      This product includes software developed by TooLs GmbH.
  24  * 4. The name of TooLs GmbH may not be used to endorse or promote products
  25  *    derived from this software without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
  28  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  29  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  30  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  31  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  32  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES ;  LOSS OF USE, DATA, OR PROFITS;
  33  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  34  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  35  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  36  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 _begin:
  40         sync
  41         isync
  42
  43         lis     %r1,stack@ha
  44         addi    %r1,%r1,stack@l
  45         addi    %r1,%r1,16384 - 0x10
  46
  47         mfmsr   %r8
  48         li      %r0,0
  49         mtmsr   %r0
  50         isync
  51
  52         mtibatu 0,%r0
  53         mtibatu 1,%r0
  54         mtibatu 2,%r0
  55         mtibatu 3,%r0
  56         mtdbatu 0,%r0
  57         mtdbatu 1,%r0
  58         mtdbatu 2,%r0
  59         mtdbatu 3,%r0
  60
  61         li      %r9,0x12             /* BATL(0, BAT_M, BAT_PP_RW) */
  62         mtibatl 0,%r9
  63         mtdbatl 0,%r9
  64         li      %r9,0x1ffe           /* BATU(0, BAT_BL_256M, BAT_Vs) */
  65         mtibatu 0,%r9
  66         mtdbatu 0,%r9
  67         isync
  68
  69         li      %r8,0x3030
  70         mtmsr   %r8
  71
  72         /* Store ofw call addr */
  73         mr      %r21,%r5
  74         lis     %r10,0xe00000@ha
  75         stw     %r5,ofw_call_addr - _start@l(%r10)
  76
  77         lis     %r4,_binary_freeldr_tmp_end@ha
  78         addi    %r4,%r4,_binary_freeldr_tmp_end@l
  79         lis     %r3,_binary_freeldr_tmp_start@ha
  80         addi    %r3,%r3,_binary_freeldr_tmp_start@l
  81
  82         lis     %r5,0x8000@ha
  83         addi    %r5,%r5,0x8000@l
  84
  85         bl      copy_bits
  86
  87         bl      zero_registers
  88
  89         lis     %r3,0xe00000@ha
  90         addi    %r3,%r3,freeldr_banner - _start
  91
  92         bl      ofw_print_string
  93
  94         bl      ofw_print_eol
  95
  96         /* Zero CTR */
  97         mtcr    %r31
  98
  99         lis     %r3,0x8000@ha
 100         addi    %r3,%r3,0x8000@l
 101
 102         mtlr    %r3
 103
 104         lis     %r3,call_ofw@ha
 105         addi    %r3,%r3,call_ofw - _start
 106
 107         b       call_freeldr
 108
 109         .align  4
 110 call_freeldr:
 111         /* Get the address of the functions list --
 112          * Note:
 113          * Because of little endian switch we must use an even number of
 114          * instructions here..  Pad with a nop if needed. */
 115         mfmsr   %r10
 116         ori     %r10,%r10,1
 117         mtmsr   %r10
 118
 119         nop
 120
 121         /* Note that this is little-endian from here on */
 122         blr
 123         nop
 124
 125         .align  4
 126 call_ofw:
 127         /* R3 has the function offset to call (n * 4)
 128          * Other arg registers are unchanged.
 129          * Note that these 4 instructions are in reverse order due to
 130          * little-endian convention */
 131         andi.   %r0,%r0,65534
 132         mfmsr   %r0
 133         mtmsr   %r0
 134         /* Now normal ordering resumes */
 135         subi    %r1,%r1,0x100
 136
 137         stw     %r8,4(%r1)
 138         stw     %r9,8(%r1)
 139         stw     %r10,12(%r1)
 140         mflr    %r8
 141         stw     %r8,16(%r1)
 142
 143         lis     %r10,0xe00000@ha
 144         add     %r9,%r3,%r10
 145         lwz     %r3,ofw_functions - _start@l(%r9)
 146         mtctr   %r3
 147
 148         mr      %r3,%r4
 149         mr      %r4,%r5
 150         mr      %r5,%r6
 151         mr      %r6,%r7
 152         mr      %r7,%r8
 153
 154         /* Goto the swapped function */
 155         bctrl
 156
 157         lwz     %r8,16(%r1)
 158         mtlr    %r8
 159
 160         lwz     %r8,4(%r1)
 161         lwz     %r9,8(%r1)
 162         lwz     %r10,12(%r1)
 163
 164         addi    %r1,%r1,0x100
 165         /* Ok, go back to little endian */
 166         mfmsr   %r0
 167         ori     %r0,%r0,1
 168         mtmsr   %r0
 169
 170         /* Note that this is little-endian from here on */
 171         blr
 172         nop
 173
 174 zero_registers:
 175         xor     %r2,%r2,%r2
 176         mr      %r0,%r2
 177         mr      %r3,%r2
 178
 179         mr      %r4,%r2
 180         mr      %r5,%r2
 181         mr      %r6,%r2
 182         mr      %r7,%r2
 183
 184         mr      %r8,%r2
 185         mr      %r9,%r2
 186         mr      %r10,%r2
 187         mr      %r11,%r2
 188
 189         mr      %r12,%r2
 190         mr      %r13,%r2
 191         mr      %r14,%r2
 192         mr      %r15,%r2
 193
 194         mr      %r12,%r2
 195         mr      %r13,%r2
 196         mr      %r14,%r2
 197         mr      %r15,%r2
 198
 199         mr      %r16,%r2
 200         mr      %r17,%r2
 201         mr      %r18,%r2
 202         mr      %r19,%r2
 203
 204         mr      %r20,%r2
 205         mr      %r21,%r2
 206         mr      %r22,%r2
 207         mr      %r23,%r2
 208
 209         mr      %r24,%r2
 210         mr      %r25,%r2
 211         mr      %r26,%r2
 212         mr      %r27,%r2
 213
 214         mr      %r28,%r2
 215         mr      %r29,%r2
 216         mr      %r30,%r2
 217         mr      %r31,%r2
 218
 219         blr
 220
 221 prim_strlen:
 222         mr      %r5,%r3
 223 prim_strlen_loop:
 224         lbz     %r4,0(%r3)
 225         cmpi    0,0,%r4,0
 226         beq     prim_strlen_done
 227         addi    %r3,%r3,1
 228         b       prim_strlen_loop
 229
 230 prim_strlen_done:
 231         sub     %r3,%r3,%r5
 232         blr
 233
 234 copy_bits:
 235         cmp     0,0,%r3,%r4
 236         beqlr
 237         lwz     %r6,0(%r3)
 238         stw     %r6,0(%r5)
 239         addi    %r3,%r3,4
 240         addi    %r5,%r5,4
 241         b       copy_bits
 242
 243 ofw_print_string_hook:
 244         bl      ofw_print_number
 245         bl      ofw_exit
 246
 247 ofw_print_string:
 248         /* Reserve some stack space */
 249         subi    %r1,%r1,32
 250
 251         /* Save args */
 252         stw     %r3,0(%r1)
 253
 254         /* Save the lr, a scratch register */
 255         stw     %r8,8(%r1)
 256         mflr    %r8
 257         stw     %r8,12(%r1)
 258
 259         /* Load the package name */
 260         lis     %r3,0xe00000@ha
 261         addi    %r3,%r3,ofw_chosen_name - _start
 262
 263         /* Fire */
 264         bl      ofw_finddevice
 265
 266         /* Load up for getprop */
 267         stw     %r3,16(%r1)
 268
 269         lis     %r4,0xe00000@ha
 270         addi    %r4,%r4,ofw_stdout_name - _start
 271
 272         addi    %r5,%r1,20
 273
 274         li      %r6,4
 275
 276         bl      ofw_getprop
 277
 278         /* Measure the string and remember the length */
 279         lwz     %r3,0(%r1)
 280         bl      prim_strlen
 281         mr      %r5,%r3
 282
 283         lwz     %r3,20(%r1)
 284         lwz     %r4,0(%r1)
 285
 286         /* Write the string */
 287         bl      ofw_write
 288
 289         /* Return */
 290         lwz     %r8,12(%r1)
 291         mtlr    %r8
 292         lwz     %r8,8(%r1)
 293
 294         addi    %r1,%r1,32
 295         blr
 296
 297         /* Print 8 hex digits representing a number in r3 */
 298 ofw_print_number:
 299         subi    %r1,%r1,32
 300         stw     %r8,0(%r1)
 301         mflr    %r8
 302         stw     %r8,4(%r1)
 303         stw     %r9,8(%r1)
 304
 305         xor     %r9,%r9,%r9
 306         stw     %r9,12(%r1)
 307
 308         /* Set up and, devide, shift */
 309         mr      %r8,%r3
 310         lis     %r6,0xf0000000@ha
 311         lis     %r7,0x10000000@ha
 312         li      %r9,8
 313
 314 ofw_number_loop:
 315         nop
 316         cmpi    0,0,%r9,0
 317         beq     ofw_number_return
 318         subi    %r9,%r9,1
 319
 320         /* Body: isolate digit, divide, print */
 321         and     %r5,%r6,%r8
 322         divwu   %r4,%r5,%r7
 323         srwi    %r6,%r6,4
 324         srwi    %r7,%r7,4
 325
 326         nop
 327
 328         cmpi    0,0,%r4,10
 329         bge     ofw_number_letter
 330         addi    %r4,%r4,'0'
 331         b       ofw_number_digit_out
 332
 333 ofw_number_letter:
 334         addi    %r4,%r4,'A' - 10
 335
 336 ofw_number_digit_out:
 337         stb     %r4,12(%r1)
 338         addi    %r3,%r1,12
 339
 340         stw     %r6,16(%r1)
 341         stw     %r7,20(%r1)
 342         stw     %r8,24(%r1)
 343         stw     %r9,28(%r1)
 344
 345         bl      ofw_print_string
 346
 347         lwz     %r6,16(%r1)
 348         lwz     %r7,20(%r1)
 349         lwz     %r8,24(%r1)
 350         lwz     %r9,28(%r1)
 351
 352         b       ofw_number_loop
 353
 354 ofw_number_return:
 355         /* Return */
 356         lwz     %r9,8(%r1)
 357         lwz     %r8,4(%r1)
 358         mtlr    %r8
 359         lwz     %r8,0(%r1)
 360         addi    %r1,%r1,32
 361         blr
 362
 363 ofw_print_eol:
 364         subi    %r1,%r1,16
 365         stw     %r8,0(%r1)
 366         mflr    %r8
 367         stw     %r8,4(%r1)
 368         li      %r4,0x0d0a
 369         sth     %r4,8(%r1)
 370         xor     %r4,%r4,%r4
 371         sth     %r4,10(%r1)
 372         addi    %r3,%r1,8
 373         bl      ofw_print_string
 374         lwz     %r8,4(%r1)
 375         mtlr    %r8
 376         lwz     %r8,0(%r1)
 377         addi    %r1,%r1,16
 378         blr
 379
 380 ofw_print_nothing:
 381         subi    %r1,%r1,16
 382         stw     %r8,0(%r1)
 383         mflr    %r8
 384         stw     %r8,4(%r1)
 385         li      %r4,0
 386         sth     %r4,8(%r1)
 387         xor     %r4,%r4,%r4
 388         sth     %r4,10(%r1)
 389         addi    %r3,%r1,8
 390         bl      ofw_print_string
 391         lwz     %r8,4(%r1)
 392         mtlr    %r8
 393         lwz     %r8,0(%r1)
 394         addi    %r1,%r1,16
 395         blr
 396
 397 ofw_print_space:
 398         subi    %r1,%r1,16
 399         stw     %r8,0(%r1)
 400         mflr    %r8
 401         stw     %r8,4(%r1)
 402         li      %r4,0x2000
 403         sth     %r4,8(%r1)
 404         xor     %r4,%r4,%r4
 405         sth     %r4,10(%r1)
 406         addi    %r3,%r1,8
 407         bl      ofw_print_string
 408         lwz     %r8,4(%r1)
 409         mtlr    %r8
 410         lwz     %r8,0(%r1)
 411         addi    %r1,%r1,16
 412         blr
 413
 414 ofw_print_regs:
 415         /* Construct ofw exit call */
 416         subi    %r1,%r1,0xa0
 417
 418         stw     %r0,0(%r1)
 419         stw     %r1,4(%r1)
 420         stw     %r2,8(%r1)
 421         stw     %r3,12(%r1)
 422
 423         stw     %r4,16(%r1)
 424         stw     %r5,20(%r1)
 425         stw     %r6,24(%r1)
 426         stw     %r7,28(%r1)
 427
 428         stw     %r8,32(%r1)
 429         stw     %r9,36(%r1)
 430         stw     %r10,40(%r1)
 431         stw     %r11,44(%r1)
 432
 433         stw     %r12,48(%r1)
 434         stw     %r13,52(%r1)
 435         stw     %r14,56(%r1)
 436         stw     %r15,60(%r1)
 437
 438         stw     %r16,64(%r1)
 439         stw     %r17,68(%r1)
 440         stw     %r18,72(%r1)
 441         stw     %r19,76(%r1)
 442
 443         stw     %r20,80(%r1)
 444         stw     %r21,84(%r1)
 445         stw     %r22,88(%r1)
 446         stw     %r23,92(%r1)
 447
 448         stw     %r24,96(%r1)
 449         stw     %r25,100(%r1)
 450         stw     %r26,104(%r1)
 451         stw     %r27,108(%r1)
 452
 453         stw     %r28,112(%r1)
 454         stw     %r29,116(%r1)
 455         stw     %r30,120(%r1)
 456         stw     %r31,124(%r1)
 457
 458         mflr    %r0
 459         stw     %r0,128(%r1)
 460         mfcr    %r0
 461         stw     %r0,132(%r1)
 462         mfctr   %r0
 463         stw     %r0,136(%r1)
 464         mfmsr   %r0
 465         stw     %r0,140(%r1)
 466
 467         /* Count at zero */
 468         xor     %r0,%r0,%r0
 469         stw     %r0,144(%r1)
 470         mr      %r3,%r1
 471         stw     %r3,148(%r1)
 472
 473         /* Body, print the regname, then the register */
 474 ofw_register_loop:
 475         lwz     %r3,144(%r1)
 476         cmpi    0,0,%r3,32
 477         beq     ofw_register_special
 478         lis     %r3,0xe00000@ha
 479         addi    %r3,%r3,freeldr_reg_init - _start
 480         bl      ofw_print_string
 481         lwz     %r3,144(%r1)
 482         bl      ofw_print_number
 483         bl      ofw_print_space
 484         lwz     %r3,144(%r1)
 485         mulli   %r3,%r3,4
 486         add     %r3,%r1,%r3
 487         lwz     %r3,0(%r3)
 488         stw     %r3,152(%r1)
 489         bl      ofw_print_number
 490         lwz     %r3,144(%r1)
 491         addi    %r3,%r3,1
 492         stw     %r3,144(%r1)
 493         b       done_dump
 494
 495 dump_optional:
 496         bl      ofw_print_space
 497         bl      ofw_print_space
 498         lwz     %r3,152(%r1)
 499         lwz     %r3,0(%r3)
 500         bl      ofw_print_number
 501         bl      ofw_print_space
 502         lwz     %r3,152(%r1)
 503         lwz     %r3,4(%r3)
 504         bl      ofw_print_number
 505         bl      ofw_print_space
 506         lwz     %r3,152(%r1)
 507         lwz     %r3,8(%r3)
 508         bl      ofw_print_number
 509         bl      ofw_print_space
 510         lwz     %r3,152(%r1)
 511         lwz     %r3,12(%r3)
 512         bl      ofw_print_number
 513         bl      ofw_print_space
 514 done_dump:
 515         bl      ofw_print_eol
 516         b       ofw_register_loop
 517
 518 ofw_register_special:
 519         /* LR */
 520         lis     %r3,0xe00000@ha
 521         addi    %r3,%r3,freeldr_reg_lr - _start
 522         bl      ofw_print_string
 523         bl      ofw_print_space
 524         lwz     %r3,128(%r1)
 525         bl      ofw_print_number
 526         bl      ofw_print_eol
 527
 528         /* CR */
 529         lis     %r3,0xe00000@ha
 530         addi    %r3,%r3,freeldr_reg_cr - _start
 531         bl      ofw_print_string
 532         bl      ofw_print_space
 533         lwz     %r3,132(%r1)
 534         bl      ofw_print_number
 535         bl      ofw_print_eol
 536
 537         /* CTR */
 538         lis     %r3,0xe00000@ha
 539         addi    %r3,%r3,freeldr_reg_ctr - _start
 540         bl      ofw_print_string
 541         bl      ofw_print_space
 542         lwz     %r3,136(%r1)
 543         bl      ofw_print_number
 544         bl      ofw_print_eol
 545
 546         /* MSR */
 547         lis     %r3,0xe00000@ha
 548         addi    %r3,%r3,freeldr_reg_msr - _start
 549         bl      ofw_print_string
 550         bl      ofw_print_space
 551         lwz     %r3,140(%r1)
 552         bl      ofw_print_number
 553         bl      ofw_print_eol
 554
 555         /* Return */
 556         lwz     %r0,128(%r1)
 557         mtlr    %r0
 558
 559         lwz     %r0,0(%r1)
 560         lwz     %r2,8(%r1)
 561         lwz     %r3,12(%r1)
 562
 563         lwz     %r4,16(%r1)
 564         lwz     %r5,20(%r1)
 565         lwz     %r6,24(%r1)
 566         lwz     %r7,28(%r1)
 567
 568         addi    %r1,%r1,0xa0
 569
 570         blr
 571
 572 ofw_finddevice_hook:
 573         subi    %r1,%r1,32
 574         stw     %r3,0(%r1)
 575         mflr    %r3
 576         stw     %r3,4(%r1)
 577         lwz     %r3,0(%r1)
 578         bl      ofw_finddevice
 579         stw     %r3,0(%r1)
 580         lwz     %r3,4(%r1)
 581         mtlr    %r3
 582         lwz     %r3,0(%r1)
 583         addi    %r1,%r1,32
 584         blr
 585
 586 ofw_finddevice:
 587         /* Reserve stack space ...
 588          * 20 bytes for the ofw call,
 589          * r8, r9, and lr */
 590         subi    %r1,%r1,32
 591
 592         /* Store r8, r9, lr */
 593         stw     %r8,20(%r1)
 594         stw     %r9,24(%r1)
 595         mflr    %r8
 596         stw     %r8,28(%r1)
 597
 598         /* Get finddevice name */
 599         lis     %r8,0xe00000@ha
 600         addi    %r9,%r8,ofw_finddevice_name - _start
 601         stw     %r9,0(%r1)
 602
 603         /* 1 Argument and 1 return */
 604         li      %r9,1
 605         stw     %r9,4(%r1)
 606         stw     %r9,8(%r1)
 607
 608         stw     %r3,12(%r1)
 609
 610         /* Load up the call address */
 611         lwz     %r9,ofw_call_addr - _start(%r8)
 612         mtlr    %r9
 613
 614         /* Set argument */
 615         mr      %r3,%r1
 616
 617         /* Fire */
 618         blrl
 619
 620         lwz     %r3,16(%r1)
 621
 622         /* Restore registers */
 623         lwz     %r8,28(%r1)
 624         mtlr    %r8
 625         lwz     %r9,24(%r1)
 626         lwz     %r8,20(%r1)
 627
 628         addi    %r1,%r1,32
 629
 630         /* Return */
 631         blr
 632
 633 ofw_getprop_hook:
 634         /* Reserve stack space:
 635          * 32 bytes for the ofw call
 636          * 12 bytes for r8, r9, lr
 637          */
 638         /* Reserve stack space ...
 639          * 20 bytes for the ofw call,
 640          * r8, r9, and lr */
 641         subi    %r1,%r1,48
 642
 643         /* Store r8, r9, lr */
 644         stw     %r8,32(%r1)
 645         stw     %r9,36(%r1)
 646         mflr    %r8
 647         stw     %r8,40(%r1)
 648
 649         /* Get getprop name */
 650         lis     %r8,0xe00000@ha
 651         addi    %r9,%r8,ofw_getprop_name - _start
 652         stw     %r9,0(%r1)
 653
 654         /* 4 Argument and 1 return */
 655         li      %r9,4
 656         stw     %r9,4(%r1)
 657         li      %r9,1
 658         stw     %r9,8(%r1)
 659
 660         stw     %r3,12(%r1) /* Package */
 661         stw     %r4,16(%r1) /* Property */
 662         stw     %r5,20(%r1) /* Return buffer */
 663         stw     %r6,24(%r1) /* Buffer size */
 664
 665         /* Load up the call address */
 666         lwz     %r9,ofw_call_addr - _start(%r8)
 667         mtlr    %r9
 668
 669         /* Set argument */
 670         mr      %r3,%r1
 671
 672         /* Fire */
 673         blrl
 674
 675         /* Workaround to a wierd crash ... not sure what causes it.
 676          * XXX investigate me */
 677         bl      ofw_print_nothing
 678
 679         /* Return */
 680         lwz     %r3,28(%r1)
 681
 682         /* Restore registers */
 683         lwz     %r8,40(%r1)
 684         mtlr    %r8
 685         lwz     %r9,36(%r1)
 686         lwz     %r8,32(%r1)
 687
 688         addi    %r1,%r1,48
 689
 690         /* Return */
 691         blr
 692
 693 ofw_getprop:
 694         /* Reserve stack space:
 695          * 32 bytes for the ofw call
 696          * 12 bytes for r8, r9, lr
 697          */
 698         /* Reserve stack space ...
 699          * 20 bytes for the ofw call,
 700          * r8, r9, and lr */
 701         subi    %r1,%r1,48
 702
 703         /* Store r8, r9, lr */
 704         stw     %r8,32(%r1)
 705         stw     %r9,36(%r1)
 706         mflr    %r8
 707         stw     %r8,40(%r1)
 708
 709         /* Get getprop name */
 710         lis     %r8,0xe00000@ha
 711         addi    %r9,%r8,ofw_getprop_name - _start
 712         stw     %r9,0(%r1)
 713
 714         /* 4 Argument and 1 return */
 715         li      %r9,4
 716         stw     %r9,4(%r1)
 717         li      %r9,1
 718         stw     %r9,8(%r1)
 719
 720         stw     %r3,12(%r1) /* Package */
 721         stw     %r4,16(%r1) /* Property */
 722         stw     %r5,20(%r1) /* Return buffer */
 723         stw     %r6,24(%r1) /* Buffer size */
 724
 725         /* Load up the call address */
 726         lwz     %r9,ofw_call_addr - _start(%r8)
 727         mtlr    %r9
 728
 729         /* Set argument */
 730         mr      %r3,%r1
 731
 732         /* Fire */
 733         blrl
 734
 735         /* Return */
 736         lwz     %r3,28(%r1)
 737
 738         /* Restore registers */
 739         lwz     %r8,40(%r1)
 740
 741         mtlr    %r8
 742         lwz     %r9,36(%r1)
 743         lwz     %r8,32(%r1)
 744
 745         addi    %r1,%r1,48
 746
 747         /* Return */
 748         blr
 749
 750 ofw_write:
 751         /* Reserve stack space:
 752          * 28 bytes for the ofw call
 753          * 12 bytes for r8, r9, lr
 754          */
 755         /* Reserve stack space ...
 756          * 20 bytes for the ofw call,
 757          * r8, r9, and lr */
 758         subi    %r1,%r1,48
 759
 760         nop
 761
 762         /* Store r8, r9, lr */
 763         stw     %r8,28(%r1)
 764         stw     %r9,32(%r1)
 765         mflr    %r8
 766         stw     %r8,36(%r1)
 767
 768         /* Get write name */
 769         lis     %r8,0xe00000@ha
 770         addi    %r9,%r8,ofw_write_name - _start
 771         stw     %r9,0(%r1)
 772
 773         /* 3 Arguments and 1 return */
 774         li      %r9,3
 775         stw     %r9,4(%r1)
 776         li      %r9,1
 777         stw     %r9,8(%r1)
 778
 779         stw     %r3,12(%r1)
 780         stw     %r4,16(%r1)
 781         stw     %r5,20(%r1)
 782
 783         /* Load up the call address */
 784         lwz     %r9,ofw_call_addr - _start(%r8)
 785         mtlr    %r9
 786
 787         /* Set argument */
 788         mr      %r3,%r1
 789
 790         /* Fire */
 791         blrl
 792
 793         /* Return */
 794         lwz     %r3,24(%r1)
 795
 796         /* Restore registers */
 797         lwz     %r8,36(%r1)
 798         mtlr    %r8
 799         lwz     %r9,32(%r1)
 800         lwz     %r8,28(%r1)
 801
 802         addi    %r1,%r1,48
 803
 804         /* Return */
 805         blr
 806
 807 ofw_read:
 808         /* Reserve stack space:
 809          * 28 bytes for the ofw call
 810          * 12 bytes for r8, r9, lr
 811          */
 812         /* Reserve stack space ...
 813          * 20 bytes for the ofw call,
 814          * r8, r9, and lr */
 815         subi    %r1,%r1,48
 816
 817         nop
 818
 819         /* Store r8, r9, lr */
 820         stw     %r8,28(%r1)
 821         stw     %r9,32(%r1)
 822         mflr    %r8
 823         stw     %r8,36(%r1)
 824
 825         /* Get read name */
 826         lis     %r8,0xe00000@ha
 827         addi    %r9,%r8,ofw_read_name - _start
 828         stw     %r9,0(%r1)
 829
 830         /* 3 Arguments and 1 return */
 831         li      %r9,3
 832         stw     %r9,4(%r1)
 833         li      %r9,1
 834         stw     %r9,8(%r1)
 835
 836         stw     %r3,12(%r1)
 837         stw     %r4,16(%r1)
 838         stw     %r5,20(%r1)
 839
 840         /* Load up the call address */
 841         lwz     %r9,ofw_call_addr - _start(%r8)
 842         mtlr    %r9
 843
 844         /* Set argument */
 845         mr      %r3,%r1
 846
 847         /* Fire */
 848         blrl
 849
 850         /* Return */
 851         lwz     %r3,24(%r1)
 852
 853         /* Restore registers */
 854         lwz     %r8,36(%r1)
 855         mtlr    %r8
 856         lwz     %r9,32(%r1)
 857         lwz     %r8,28(%r1)
 858
 859         addi    %r1,%r1,48
 860
 861         /* Return */
 862         blr
 863
 864 ofw_exit:
 865         lis     %r3,0xe00000@ha
 866         addi    %r3,%r3,freeldr_halt - _start
 867
 868         bl      ofw_print_string
 869 /*
 870 ofw_exit_loop:
 871         b       ofw_exit_loop
 872 */
 873         /* Load the exit name */
 874         lis     %r8,0xe00000@ha
 875         addi    %r9,%r8,ofw_exit_name - _start
 876         stw     %r9,0(%r1)
 877
 878         /* Zero args, zero returns */
 879         xor     %r9,%r9,%r9
 880         stw     %r9,4(%r1)
 881         stw     %r9,8(%r1)
 882
 883         /* Load up the call address */
 884         lwz     %r9,ofw_call_addr - _start(%r8)
 885         mtlr    %r9
 886
 887         mr      %r3,%r1
 888
 889         /* Fire */
 890         blrl
 891         /* No return from exit */
 892
 893         .org    0x1000
 894 freeldr_banner:
 895         .ascii  "ReactOS OpenFirmware Boot Program\r\n\0"
 896
 897 freeldr_halt:
 898         .ascii  "ReactOS OpenFirmware Boot Program Halting\r\n\0"
 899
 900 freeldr_reg_init:
 901         .ascii  "r\0"
 902
 903 freeldr_reg_lr:
 904         .ascii  "lr \0"
 905 freeldr_reg_cr:
 906         .ascii  "cr \0"
 907 freeldr_reg_ctr:
 908         .ascii  "ctr\0"
 909 freeldr_reg_msr:
 910         .ascii  "msr\0"
 911
 912 ofw_call_addr:
 913         .long   0
 914
 915 ofw_memory_size:
 916         .long   0
 917         .long   0
 918         .long   0
 919         .long   0
 920
 921 ofw_finddevice_name:
 922         .ascii  "finddevice\0"
 923
 924 ofw_getprop_name:
 925         .ascii  "getprop\0"
 926
 927 ofw_write_name:
 928         .ascii  "write\0"
 929
 930 ofw_read_name:
 931         .ascii  "read\0"
 932
 933 ofw_exit_name:
 934         .ascii  "exit\0"
 935
 936 ofw_chosen_name:
 937         .ascii  "/chosen\0"
 938
 939 ofw_stdout_name:
 940         .ascii  "stdout\0"
 941
 942 ofw_memory_name:
 943         .ascii  "/memory@0\0"
 944
 945 ofw_reg_name:
 946         .ascii  "reg\0"
 947
 948 ofw_functions:
 949         .long   ofw_finddevice_hook
 950         .long   ofw_getprop_hook
 951         .long   ofw_write
 952         .long   ofw_read
 953         .long   ofw_exit
 954         .long   ofw_print_regs
 955         .long   ofw_print_string
 956         .long   ofw_print_number
 957
 958         .org    0x2000
 959 stack:
 960         .space  0x4000