1#------------------------------------------------------------------------------ 2#* 3#* Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR> 4#* This program and the accompanying materials 5#* are licensed and made available under the terms and conditions of the BSD License 6#* which accompanies this distribution. The full text of the license may be found at 7#* http://opensource.org/licenses/bsd-license.php 8#* 9#* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 10#* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 11#* 12#* st32_64.asm 13#* 14#* Abstract: 15#* 16#------------------------------------------------------------------------------ 17 18 19 .stack: 20 .486p: 21 .code16 22 23.equ FAT_DIRECTORY_ENTRY_SIZE, 0x020 24.equ FAT_DIRECTORY_ENTRY_SHIFT, 5 25.equ BLOCK_SIZE, 0x0200 26.equ BLOCK_MASK, 0x01ff 27.equ BLOCK_SHIFT, 9 28 29 .org 0x0 30 31.global _start 32_start: 33 34Ia32Jump: 35 jmp BootSectorEntryPoint # JMP inst - 3 bytes 36 nop 37 38OemId: .ascii "INTEL " # OemId - 8 bytes 39SectorSize: .word 0 # Sector Size - 2 bytes 40SectorsPerCluster: .byte 0 # Sector Per Cluster - 1 byte 41ReservedSectors: .word 0 # Reserved Sectors - 2 bytes 42NoFats: .byte 0 # Number of FATs - 1 byte 43RootEntries: .word 0 # Root Entries - 2 bytes 44Sectors: .word 0 # Number of Sectors - 2 bytes 45Media: .byte 0 # Media - 1 byte 46SectorsPerFat16: .word 0 # Sectors Per FAT for FAT12/FAT16 - 2 byte 47SectorsPerTrack: .word 0 # Sectors Per Track - 2 bytes 48Heads: .word 0 # Heads - 2 bytes 49HiddenSectors: .long 0 # Hidden Sectors - 4 bytes 50LargeSectors: .long 0 # Large Sectors - 4 bytes 51 52#****************************************************************************** 53# 54#The structure for FAT32 starting at offset 36 of the boot sector. (At this point, 55#the BPB/boot sector for FAT12 and FAT16 differs from the BPB/boot sector for FAT32.) 56# 57#****************************************************************************** 58 59SectorsPerFat32: .long 0 # Sectors Per FAT for FAT32 - 4 bytes 60ExtFlags: .word 0 # Mirror Flag - 2 bytes 61FSVersion: .word 0 # File System Version - 2 bytes 62RootCluster: .long 0 # 1st Cluster Number of Root Dir - 4 bytes 63FSInfo: .word 0 # Sector Number of FSINFO - 2 bytes 64BkBootSector: .word 0 # Sector Number of Bk BootSector - 2 bytes 65Reserved: .fill 12,1,0 # Reserved Field - 12 bytes 66PhysicalDrive: .byte 0 # Physical Drive Number - 1 byte 67Reserved1: .byte 0 # Reserved Field - 1 byte 68Signature: .byte 0 # Extended Boot Signature - 1 byte 69VolId: .ascii " " # Volume Serial Number - 4 bytes 70FatLabel: .ascii " " # Volume Label - 11 bytes 71FileSystemType: .ascii "FAT32 " # File System Type - 8 bytes 72 73 74BootSectorEntryPoint: 75 # ASSUME ds:@code 76 # ASSUME ss:@code 77 # ds = 1000, es = 2000 + x (size of first cluster >> 4) 78 # cx = Start Cluster of EfiLdr 79 # dx = Start Cluster of Efivar.bin 80 81# Re use the BPB data stored in Boot Sector 82 movw $0x7c00,%bp 83 84 pushw %cx 85# Read Efivar.bin 86# 1000:dx = DirectoryEntry of Efivar.bin -> BS.com has filled already 87 movw $0x1900,%ax 88 movw %ax,%es 89 testw %dx,%dx 90 jnz CheckVarStoreSize 91 92 movb $1,%al 93NoVarStore: 94 pushw %es 95# Set the 5th byte start @ 0:19000 to non-zero indicating we should init var store header in DxeIpl 96 movb %al, %es:(4) 97 jmp SaveVolumeId 98 99CheckVarStoreSize: 100 movw %dx,%di 101 cmpl $0x4000, %ds:2(%di) 102 movb $2,%al 103 jne NoVarStore 104 105LoadVarStore: 106 movb $0,%al 107 movb %al, %es:(4) 108 movw (%di), %cx 109# ES:DI = 1500:0 110 xorw %di,%di 111 pushw %es 112 movw $0x1500,%ax 113 movw %ax,%es 114 call ReadFile 115SaveVolumeId: 116 popw %es 117 movw VolId(%bp), %ax 118 movw %ax, %es:(0) # Save Volume Id to 0:19000. we will find the correct volume according to this VolumeId 119 movw VolId+2(%bp), %ax 120 movw %ax, %es:(2) 121 122# Read Efildr 123 popw %cx 124# cx = Start Cluster of Efildr -> BS.com has filled already 125# ES:DI = 2000:0, first cluster will be read again 126 xorw %di,%di # di = 0 127 movw $0x2000,%ax 128 movw %ax,%es 129 call ReadFile 130 movw %cs,%ax 131 movw %ax, %cs:JumpSegment 132 133CheckEm64T: 134 movl $0x80000001,%eax 135# cpuid 136 .word 0xA20F 137 btl $29,%edx 138 jc CheckEm64TPass 139 pushw %cs 140 popw %ds 141 leaw Em64String,%si 142 movw $18,%cx 143 jmp PrintStringAndHalt 144CheckEm64TPass: 145JumpFarInstruction: 146 .byte 0xea 147JumpOffset: 148 .word 0x200 149JumpSegment: 150 .word 0x2000 151 152 153 154# **************************************************************************** 155# ReadFile 156# 157# Arguments: 158# CX = Start Cluster of File 159# ES:DI = Buffer to store file content read from disk 160# 161# Return: 162# (ES << 4 + DI) = end of file content Buffer 163# 164# **************************************************************************** 165ReadFile: 166# si = NumberOfClusters 167# cx = ClusterNumber 168# dx = CachedFatSectorNumber 169# ds:0000 = CacheFatSectorBuffer 170# es:di = Buffer to load file 171# bx = NextClusterNumber 172 pusha 173 movw $1,%si # NumberOfClusters = 1 174 pushw %cx # Push Start Cluster onto stack 175 movw $0xfff,%dx # CachedFatSectorNumber = 0xfff 176FatChainLoop: 177 movw %cx,%ax # ax = ClusterNumber 178 andw $0xfff8,%ax # ax = ax & 0xfff8 179 cmpw $0xfff8,%ax # See if this is the last cluster 180 je FoundLastCluster # Jump if last cluster found 181 movw %cx,%ax # ax = ClusterNumber 182 shlw $2, %ax # FatOffset = ClusterNumber * 2 183 pushw %si # Save si 184 movw %ax,%si # si = FatOffset 185 shrw $BLOCK_SHIFT, %ax # ax = FatOffset >> BLOCK_SHIFT 186 addw ReservedSectors(%bp), %ax # ax = FatSectorNumber = ReservedSectors + (FatOffset >> BLOCK_OFFSET) 187 andw $BLOCK_MASK, %si # si = FatOffset & BLOCK_MASK 188 cmpw %dx,%ax # Compare FatSectorNumber to CachedFatSectorNumber 189 je SkipFatRead 190 movw $2,%bx 191 pushw %es 192 pushw %ds 193 popw %es 194 call ReadBlocks # Read 2 blocks starting at AX storing at ES:DI 195 popw %es 196 movw %ax,%dx # CachedFatSectorNumber = FatSectorNumber 197SkipFatRead: 198 movw (%si), %bx # bx = NextClusterNumber 199 movw %cx,%ax # ax = ClusterNumber 200 popw %si # Restore si 201 decw %bx # bx = NextClusterNumber - 1 202 cmpw %cx,%bx # See if (NextClusterNumber-1)==ClusterNumber 203 jne ReadClusters 204 incw %bx # bx = NextClusterNumber 205 incw %si # NumberOfClusters++ 206 movw %bx,%cx # ClusterNumber = NextClusterNumber 207 jmp FatChainLoop 208ReadClusters: 209 incw %bx 210 popw %ax # ax = StartCluster 211 pushw %bx # StartCluster = NextClusterNumber 212 movw %bx,%cx # ClusterNumber = NextClusterNumber 213 subw $2,%ax # ax = StartCluster - 2 214 xorb %bh,%bh 215 movb SectorsPerCluster(%bp), %bl # bx = SectorsPerCluster 216 mulw %bx # ax = (StartCluster - 2) * SectorsPerCluster 217 addw (%bp), %ax # ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster 218 pushw %ax # save start sector 219 movw %si,%ax # ax = NumberOfClusters 220 mulw %bx # ax = NumberOfClusters * SectorsPerCluster 221 movw %ax,%bx # bx = Number of Sectors 222 popw %ax # ax = Start Sector 223 call ReadBlocks 224 movw $1,%si # NumberOfClusters = 1 225 jmp FatChainLoop 226FoundLastCluster: 227 popw %cx 228 popa 229 ret 230 231 232# **************************************************************************** 233# ReadBlocks - Reads a set of blocks from a block device 234# 235# AX = Start LBA 236# BX = Number of Blocks to Read 237# ES:DI = Buffer to store sectors read from disk 238# **************************************************************************** 239 240# cx = Blocks 241# bx = NumberOfBlocks 242# si = StartLBA 243 244ReadBlocks: 245 pusha 246 addl LBAOffsetForBootSector(%bp), %eax # Add LBAOffsetForBootSector to Start LBA 247 addl HiddenSectors(%bp), %eax # Add HiddenSectors to Start LBA 248 movl %eax,%esi # esi = Start LBA 249 movw %bx,%cx # cx = Number of blocks to read 250ReadCylinderLoop: 251 movw $0x7bfc,%bp # bp = 0x7bfc 252 movl %esi,%eax # eax = Start LBA 253 xorl %edx,%edx # edx = 0 254 movzwl (%bp), %ebx # bx = MaxSector 255 divl %ebx # ax = StartLBA / MaxSector 256 incw %dx # dx = (StartLBA % MaxSector) + 1 257 258 movw (%bp), %bx # bx = MaxSector 259 subw %dx,%bx # bx = MaxSector - Sector 260 incw %bx # bx = MaxSector - Sector + 1 261 cmpw %bx,%cx # Compare (Blocks) to (MaxSector - Sector + 1) 262 jg LimitTransfer 263 movw %cx,%bx # bx = Blocks 264LimitTransfer: 265 pushw %ax # save ax 266 movw %es,%ax # ax = es 267 shrw $(BLOCK_SHIFT-4), %ax # ax = Number of blocks into mem system 268 andw $0x7f,%ax # ax = Number of blocks into current seg 269 addw %bx,%ax # ax = End Block number of transfer 270 cmpw $0x80,%ax # See if it crosses a 64K boundry 271 jle NotCrossing64KBoundry # Branch if not crossing 64K boundry 272 subw $0x80,%ax # ax = Number of blocks past 64K boundry 273 subw %ax,%bx # Decrease transfer size by block overage 274NotCrossing64KBoundry: 275 popw %ax # restore ax 276 277 pushw %cx 278 movb %dl,%cl # cl = (StartLBA % MaxSector) + 1 = Sector 279 xorw %dx,%dx # dx = 0 280 divw 2(%bp) # ax = ax / (MaxHead + 1) = Cylinder 281 # dx = ax % (MaxHead + 1) = Head 282 283 pushw %bx # Save number of blocks to transfer 284 movb %dl,%dh # dh = Head 285 movw $0x7c00,%bp # bp = 0x7c00 286 movb PhysicalDrive(%bp), %dl # dl = Drive Number 287 movb %al,%ch # ch = Cylinder 288 movb %bl,%al # al = Blocks 289 movb $2,%ah # ah = Function 2 290 movw %di,%bx # es:bx = Buffer address 291 int $0x13 292 jc DiskError 293 popw %bx 294 popw %cx 295 movzwl %bx,%ebx 296 addl %ebx,%esi # StartLBA = StartLBA + NumberOfBlocks 297 subw %bx,%cx # Blocks = Blocks - NumberOfBlocks 298 movw %es,%ax 299 shlw $(BLOCK_SHIFT-4), %bx 300 addw %bx,%ax 301 movw %ax,%es # es:di = es:di + NumberOfBlocks*BLOCK_SIZE 302 cmpw $0,%cx 303 jne ReadCylinderLoop 304 popa 305 ret 306 307DiskError: 308 pushw %cs 309 popw %ds 310 leaw ErrorString,%si 311 movw $7,%cx 312 jmp PrintStringAndHalt 313 314PrintStringAndHalt: 315 movw $0xb800,%ax 316 movw %ax,%es 317 movw $160,%di 318 rep 319 movsw 320Halt: 321 jmp Halt 322 323ErrorString: 324 .byte 'S', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, 'o', 0x0c, 'r', 0x0c, '!',0x0c 325 326 .org 0x01fa 327LBAOffsetForBootSector: 328 .long 0x0 329 330 .org 0x01fe 331 .word 0xaa55 332 333#****************************************************************************** 334#****************************************************************************** 335#****************************************************************************** 336 337.equ DELAY_PORT, 0x0ed # Port to use for 1uS delay 338.equ KBD_CONTROL_PORT, 0x060 # 8042 control port 339.equ KBD_STATUS_PORT, 0x064 # 8042 status port 340.equ WRITE_DATA_PORT_CMD, 0x0d1 # 8042 command to write the data port 341.equ ENABLE_A20_CMD, 0x0df # 8042 command to enable A20 342 343 .org 0x200 344 jmp start 345Em64String: 346.byte 'E', 0x0c, 'm', 0x0c, '6', 0x0c, '4', 0x0c, 'T', 0x0c, ' ', 0x0c, 'U', 0x0c, 'n', 0x0c, 's', 0x0c, 'u', 0x0c, 'p', 0x0c, 'p', 0x0c, 'o', 0x0c, 'r', 0x0c, 't', 0x0c, 'e', 0x0c, 'd', 0x0c, '!', 0x0c 347 348start: 349 movw %cs,%ax 350 movw %ax,%ds 351 movw %ax,%es 352 movw %ax,%ss 353 movw $MyStack, %sp 354 355# mov ax,0b800h 356# mov es,ax 357# mov byte ptr es:[160],'a' 358# mov ax,cs 359# mov es,ax 360 361 movl $0,%ebx 362 leal MemoryMap, %edi 363MemMapLoop: 364 movl $0xe820,%eax 365 movl $20,%ecx 366 movl $0x534d4150, %edx # SMAP 367 int $0x15 368 jc MemMapDone 369 addl $20,%edi 370 cmpl $0,%ebx 371 je MemMapDone 372 jmp MemMapLoop 373MemMapDone: 374 leal MemoryMap, %eax 375 subl %eax,%edi # Get the address of the memory map 376 movl %edi, MemoryMapSize # Save the size of the memory map 377 378 xorl %ebx,%ebx 379 movw %cs,%bx # BX=segment 380 shll $4,%ebx # BX="linear" address of segment base 381 leal GDT_BASE(%ebx), %eax # EAX=PHYSICAL address of gdt 382 movl %eax, (gdtr + 2) # Put address of gdt into the gdtr 383 leal IDT_BASE(%ebx), %eax # EAX=PHYSICAL address of idt 384 movl %eax, (idtr + 2) # Put address of idt into the idtr 385 leal MemoryMapSize(%ebx), %edx # Physical base address of the memory map 386 387# mov ax,0b800h 388# mov es,ax 389# mov byte ptr es:[162],'b' 390# mov ax,cs 391# mov es,ax 392 393# 394# Enable A20 Gate 395# 396 397 movw $0x2401,%ax # Enable A20 Gate 398 int $0x15 399 jnc A20GateEnabled # Jump if it suceeded 400 401# 402# If INT 15 Function 2401 is not supported, then attempt to Enable A20 manually. 403# 404 405 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller 406 jnz Timeout8042 # Jump if the 8042 timed out 407 outw %ax, $DELAY_PORT # Delay 1 uS 408 movb $WRITE_DATA_PORT_CMD, %al # 8042 cmd to write output port 409 outb %al, $KBD_STATUS_PORT # Send command to the 8042 410 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller 411 jnz Timeout8042 # Jump if the 8042 timed out 412 movb $ENABLE_A20_CMD, %al # gate address bit 20 on 413 outb %al, $KBD_CONTROL_PORT # Send command to thre 8042 414 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller 415 movw $25,%cx # Delay 25 uS for the command to complete on the 8042 416Delay25uS: 417 outw %ax, $DELAY_PORT # Delay 1 uS 418 loop Delay25uS 419Timeout8042: 420 421 422A20GateEnabled: 423 424# 425# DISABLE INTERRUPTS - Entering Protected Mode 426# 427 428 cli 429 430# mov ax,0b800h 431# mov es,ax 432# mov byte ptr es:[164],'c' 433# mov ax,cs 434# mov es,ax 435 436 leal OffsetIn32BitProtectedMode, %eax 437 addl $0x20000+0x6,%eax 438 movl %eax, OffsetIn32BitProtectedMode 439 440 leal OffsetInLongMode, %eax 441 addl $0x20000+0x6,%eax 442 movl %eax, OffsetInLongMode 443 444 # 445 # load GDT 446 # 447 .byte 0x66 448 lgdt gdtr 449 450 # 451 # Enable Protect Mode (set CR0.PE=1) 452 # 453 movl %cr0, %eax # Read CR0. 454 orl $0x1,%eax # Set PE=1 455 movl %eax, %cr0 # Write CR0. 456 .byte 0x66 457 .byte 0xea # jmp far 16:32 458OffsetIn32BitProtectedMode: 459 .long 0x0000000 # offset $+8 (In32BitProtectedMode) 460 .word 0x10 # selector (flat CS) 461In32BitProtectedMode: 462 463# 464# Entering Long Mode 465# 466 .byte 0x66 467 movw $8,%ax 468 movw %ax,%ds 469 movw %ax,%es 470 movw %ax,%ss 471 472 # 473 # Enable the 64-bit page-translation-table entries by 474 # setting CR4.PAE=1 (this is _required_ before activating 475 # long mode). Paging is not enabled until after long mode 476 # is enabled. 477 # 478 .byte 0xf 479 .byte 0x20 480 .byte 0xe0 481# mov eax, cr4 482 btsl $5,%eax 483 .byte 0xf 484 .byte 0x22 485 .byte 0xe0 486# mov cr4, eax 487 488 # 489 # This is the Trapolean Page Tables that are guarenteed 490 # under 4GB. 491 # 492 # Address Map: 493 # 10000 ~ 12000 - efildr (loaded) 494 # 20000 ~ 21000 - start64.com 495 # 21000 ~ 22000 - efi64.com 496 # 22000 ~ 90000 - efildr 497 # 90000 ~ 96000 - 4G pagetable (will be reload later) 498 # 499 .byte 0xb8 500 .long 0x90000 501# mov eax, 90000h 502 movl %eax, %cr3 503 504 # 505 # Enable long mode (set EFER.LME=1). 506 # 507 .byte 0xb9 508 .long 0xc0000080 509# mov ecx, 0c0000080h ; EFER MSR number. 510 .byte 0xf 511 .byte 0x32 512# rdmsr ; Read EFER. 513 .byte 0xf 514 .byte 0xba 515 .byte 0xe8 516 .byte 0x8 517# bts eax, 8 ; Set LME=1. 518 .byte 0xf 519 .byte 0x30 520# wrmsr ; Write EFER. 521 522 # 523 # Enable paging to activate long mode (set CR0.PG=1) 524 # 525 movl %cr0, %eax # Read CR0. 526 .byte 0xf 527 .byte 0xba 528 .byte 0xe8 529 .byte 0x1f 530# bts eax, 31 ; Set PG=1. 531 movl %eax, %cr0 # Write CR0. 532 jmp GoToLongMode 533GoToLongMode: 534 535 .byte 0x67 536 .byte 0xea # Far Jump $+9:Selector to reload CS 537OffsetInLongMode: 538 .long 00000000 # $+9 Offset is ensuing instruction boundary 539 .word 0x38 # Selector is our code selector, 38h 540 541InLongMode: 542 .byte 0x66 543 movw $0x30,%ax 544 movw %ax,%ds 545 546 .byte 0x66 547 movw $0x18,%ax 548 movw %ax,%es 549 movw %ax,%ss 550 movw %ax,%ds 551 552 .byte 0xbd 553 .long 0x400000 554# mov ebp,000400000h ; Destination of EFILDR32 555 .byte 0xbb 556 .long 0x70000 557# mov ebx,000070000h ; Length of copy 558 559 # 560 # load idt later 561 # 562 .byte 0x48 563 .byte 0x33 564 .byte 0xc0 565# xor rax, rax 566 .byte 0x66 567 movw $idtr, %ax 568 .byte 0x48 569 .byte 0x5 570 .long 0x20000 571# add rax, 20000h 572 573 .byte 0xf 574 .byte 0x1 575 .byte 0x18 576# lidt fword ptr [rax] 577 578 .byte 0x48 579 .byte 0xc7 580 .byte 0xc0 581 .long 0x21000 582# mov rax, 21000h 583 .byte 0x50 584# push rax 585 586# ret 587 .byte 0xc3 588 589Empty8042InputBuffer: 590 movw $0,%cx 591Empty8042Loop: 592 outw %ax, $DELAY_PORT # Delay 1us 593 inb $KBD_STATUS_PORT, %al # Read the 8042 Status Port 594 andb $0x2,%al # Check the Input Buffer Full Flag 595 loopnz Empty8042Loop # Loop until the input buffer is empty or a timout of 65536 uS 596 ret 597 598############################################################################## 599# data 600############################################################################## 601 602 .p2align 1 603 604 gdtr: .word GDT_END - GDT_BASE - 1 # GDT limit 605 .long 0 # (GDT base gets set above) 606############################################################################## 607# global descriptor table (GDT) 608############################################################################## 609 610 .p2align 1 611 612GDT_BASE: 613# null descriptor 614.equ NULL_SEL, .-GDT_BASE # Selector [0x0] 615 .word 0 # limit 15:0 616 .word 0 # base 15:0 617 .byte 0 # base 23:16 618 .byte 0 # type 619 .byte 0 # limit 19:16, flags 620 .byte 0 # base 31:24 621 622# linear data segment descriptor 623.equ LINEAR_SEL, .-GDT_BASE # Selector [0x8] 624 .word 0xFFFF # limit 0xFFFFF 625 .word 0 # base 0 626 .byte 0 627 .byte 0x92 # present, ring 0, data, expand-up, writable 628 .byte 0xCF # page-granular, 32-bit 629 .byte 0 630 631# linear code segment descriptor 632.equ LINEAR_CODE_SEL, .-GDT_BASE # Selector [0x10] 633 .word 0xFFFF # limit 0xFFFFF 634 .word 0 # base 0 635 .byte 0 636 .byte 0x9A # present, ring 0, data, expand-up, writable 637 .byte 0xCF # page-granular, 32-bit 638 .byte 0 639 640# system data segment descriptor 641.equ SYS_DATA_SEL, .-GDT_BASE # Selector [0x18] 642 .word 0xFFFF # limit 0xFFFFF 643 .word 0 # base 0 644 .byte 0 645 .byte 0x92 # present, ring 0, data, expand-up, writable 646 .byte 0xCF # page-granular, 32-bit 647 .byte 0 648 649# system code segment descriptor 650.equ SYS_CODE_SEL, .-GDT_BASE # Selector [0x20] 651 .word 0xFFFF # limit 0xFFFFF 652 .word 0 # base 0 653 .byte 0 654 .byte 0x9A # present, ring 0, data, expand-up, writable 655 .byte 0xCF # page-granular, 32-bit 656 .byte 0 657 658# spare segment descriptor 659.equ SPARE3_SEL, .-GDT_BASE # Selector [0x28] 660 .word 0 # limit 0xFFFFF 661 .word 0 # base 0 662 .byte 0 663 .byte 0 # present, ring 0, data, expand-up, writable 664 .byte 0 # page-granular, 32-bit 665 .byte 0 666 667# 668# system data segment descriptor 669# 670.equ SYS_DATA64_SEL, .-GDT_BASE # Selector [0x30] 671 .word 0xFFFF # limit 0xFFFFF 672 .word 0 # base 0 673 .byte 0 674 .byte 0x92 # P | DPL [1..2] | 1 | 1 | C | R | A 675 .byte 0xCF # G | D | L | AVL | Segment [19..16] 676 .byte 0 677 678# 679# system code segment descriptor 680# 681.equ SYS_CODE64_SEL, .-GDT_BASE # Selector [0x38] 682 .word 0xFFFF # limit 0xFFFFF 683 .word 0 # base 0 684 .byte 0 685 .byte 0x9A # P | DPL [1..2] | 1 | 1 | C | R | A 686 .byte 0xAF # G | D | L | AVL | Segment [19..16] 687 .byte 0 688 689# spare segment descriptor 690.equ SPARE4_SEL, .-GDT_BASE # Selector [0x40] 691 .word 0 # limit 0xFFFFF 692 .word 0 # base 0 693 .byte 0 694 .byte 0 # present, ring 0, data, expand-up, writable 695 .byte 0 # page-granular, 32-bit 696 .byte 0 697 698GDT_END: 699 700 .p2align 1 701 702 703 704idtr: .long IDT_END - IDT_BASE - 1 # IDT limit 705 .quad 0 # (IDT base gets set above) 706 707############################################################################## 708# interrupt descriptor table (IDT) 709# 710# Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ 711# mappings. This implementation only uses the system timer and all other 712# IRQs will remain masked. The descriptors for vectors 33+ are provided 713# for convenience. 714############################################################################## 715 716#idt_tag db "IDT",0 717 .p2align 1 718 719 720IDT_BASE: 721# divide by zero (INT 0) 722.equ DIV_ZERO_SEL, .-IDT_BASE 723 .word 0 # offset 15:0 724 .long SYS_CODE64_SEL # selector 15:0 725 .byte 0 # 0 for interrupt gate 726 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 727 .word 0 # offset 31:16 728 .long 0 # offset 63:32 729 .long 0 # 0 for reserved 730 731# debug exception (INT 1) 732.equ DEBUG_EXCEPT_SEL, .-IDT_BASE 733 .word 0 # offset 15:0 734 .long SYS_CODE64_SEL # selector 15:0 735 .byte 0 # 0 for interrupt gate 736 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 737 .word 0 # offset 31:16 738 .long 0 # offset 63:32 739 .long 0 # 0 for reserved 740 741# NMI (INT 2) 742.equ NMI_SEL, .-IDT_BASE 743 .word 0 # offset 15:0 744 .long SYS_CODE64_SEL # selector 15:0 745 .byte 0 # 0 for interrupt gate 746 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 747 .word 0 # offset 31:16 748 .long 0 # offset 63:32 749 .long 0 # 0 for reserved 750 751# soft breakpoint (INT 3) 752.equ BREAKPOINT_SEL, .-IDT_BASE 753 .word 0 # offset 15:0 754 .long SYS_CODE64_SEL # selector 15:0 755 .byte 0 # 0 for interrupt gate 756 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 757 .word 0 # offset 31:16 758 .long 0 # offset 63:32 759 .long 0 # 0 for reserved 760 761# overflow (INT 4) 762.equ OVERFLOW_SEL, .-IDT_BASE 763 .word 0 # offset 15:0 764 .long SYS_CODE64_SEL # selector 15:0 765 .byte 0 # 0 for interrupt gate 766 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 767 .word 0 # offset 31:16 768 .long 0 # offset 63:32 769 .long 0 # 0 for reserved 770 771# bounds check (INT 5) 772.equ BOUNDS_CHECK_SEL, .-IDT_BASE 773 .word 0 # offset 15:0 774 .long SYS_CODE64_SEL # selector 15:0 775 .byte 0 # 0 for interrupt gate 776 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 777 .word 0 # offset 31:16 778 .long 0 # offset 63:32 779 .long 0 # 0 for reserved 780 781# invalid opcode (INT 6) 782.equ INVALID_OPCODE_SEL, .-IDT_BASE 783 .word 0 # offset 15:0 784 .long SYS_CODE64_SEL # selector 15:0 785 .byte 0 # 0 for interrupt gate 786 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 787 .word 0 # offset 31:16 788 .long 0 # offset 63:32 789 .long 0 # 0 for reserved 790 791# device not available (INT 7) 792.equ DEV_NOT_AVAIL_SEL, .-IDT_BASE 793 .word 0 # offset 15:0 794 .long SYS_CODE64_SEL # selector 15:0 795 .byte 0 # 0 for interrupt gate 796 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 797 .word 0 # offset 31:16 798 .long 0 # offset 63:32 799 .long 0 # 0 for reserved 800 801# double fault (INT 8) 802.equ DOUBLE_FAULT_SEL, .-IDT_BASE 803 .word 0 # offset 15:0 804 .long SYS_CODE64_SEL # selector 15:0 805 .byte 0 # 0 for interrupt gate 806 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 807 .word 0 # offset 31:16 808 .long 0 # offset 63:32 809 .long 0 # 0 for reserved 810 811# Coprocessor segment overrun - reserved (INT 9) 812.equ RSVD_INTR_SEL1, .-IDT_BASE 813 .word 0 # offset 15:0 814 .long SYS_CODE64_SEL # selector 15:0 815 .byte 0 # 0 for interrupt gate 816 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 817 .word 0 # offset 31:16 818 .long 0 # offset 63:32 819 .long 0 # 0 for reserved 820 821# invalid TSS (INT 0ah) 822.equ INVALID_TSS_SEL, .-IDT_BASE 823 .word 0 # offset 15:0 824 .long SYS_CODE64_SEL # selector 15:0 825 .byte 0 # 0 for interrupt gate 826 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 827 .word 0 # offset 31:16 828 .long 0 # offset 63:32 829 .long 0 # 0 for reserved 830 831# segment not present (INT 0bh) 832.equ SEG_NOT_PRESENT_SEL, .-IDT_BASE 833 .word 0 # offset 15:0 834 .long SYS_CODE64_SEL # selector 15:0 835 .byte 0 # 0 for interrupt gate 836 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 837 .word 0 # offset 31:16 838 .long 0 # offset 63:32 839 .long 0 # 0 for reserved 840 841# stack fault (INT 0ch) 842.equ STACK_FAULT_SEL, .-IDT_BASE 843 .word 0 # offset 15:0 844 .long SYS_CODE64_SEL # selector 15:0 845 .byte 0 # 0 for interrupt gate 846 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 847 .word 0 # offset 31:16 848 .long 0 # offset 63:32 849 .long 0 # 0 for reserved 850 851# general protection (INT 0dh) 852.equ GP_FAULT_SEL, .-IDT_BASE 853 .word 0 # offset 15:0 854 .long SYS_CODE64_SEL # selector 15:0 855 .byte 0 # 0 for interrupt gate 856 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 857 .word 0 # offset 31:16 858 .long 0 # offset 63:32 859 .long 0 # 0 for reserved 860 861# page fault (INT 0eh) 862.equ PAGE_FAULT_SEL, .-IDT_BASE 863 .word 0 # offset 15:0 864 .long SYS_CODE64_SEL # selector 15:0 865 .byte 0 # 0 for interrupt gate 866 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 867 .word 0 # offset 31:16 868 .long 0 # offset 63:32 869 .long 0 # 0 for reserved 870 871# Intel reserved - do not use (INT 0fh) 872.equ RSVD_INTR_SEL2, .-IDT_BASE 873 .word 0 # offset 15:0 874 .long SYS_CODE64_SEL # selector 15:0 875 .byte 0 # 0 for interrupt gate 876 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 877 .word 0 # offset 31:16 878 .long 0 # offset 63:32 879 .long 0 # 0 for reserved 880 881# floating point error (INT 10h) 882.equ FLT_POINT_ERR_SEL, .-IDT_BASE 883 .word 0 # offset 15:0 884 .long SYS_CODE64_SEL # selector 15:0 885 .byte 0 # 0 for interrupt gate 886 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 887 .word 0 # offset 31:16 888 .long 0 # offset 63:32 889 .long 0 # 0 for reserved 890 891# alignment check (INT 11h) 892.equ ALIGNMENT_CHECK_SEL, .-IDT_BASE 893 .word 0 # offset 15:0 894 .long SYS_CODE64_SEL # selector 15:0 895 .byte 0 # 0 for interrupt gate 896 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 897 .word 0 # offset 31:16 898 .long 0 # offset 63:32 899 .long 0 # 0 for reserved 900 901# machine check (INT 12h) 902.equ MACHINE_CHECK_SEL, .-IDT_BASE 903 .word 0 # offset 15:0 904 .long SYS_CODE64_SEL # selector 15:0 905 .byte 0 # 0 for interrupt gate 906 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 907 .word 0 # offset 31:16 908 .long 0 # offset 63:32 909 .long 0 # 0 for reserved 910 911# SIMD floating-point exception (INT 13h) 912.equ SIMD_EXCEPTION_SEL, .-IDT_BASE 913 .word 0 # offset 15:0 914 .long SYS_CODE64_SEL # selector 15:0 915 .byte 0 # 0 for interrupt gate 916 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 917 .word 0 # offset 31:16 918 .long 0 # offset 63:32 919 .long 0 # 0 for reserved 920 921# 85 unspecified descriptors, First 12 of them are reserved, the rest are avail 922 .fill 85 * 16, 1, 0 # db (85 * 16) dup(0) 923 924# IRQ 0 (System timer) - (INT 68h) 925.equ IRQ0_SEL, .-IDT_BASE 926 .word 0 # offset 15:0 927 .long SYS_CODE64_SEL # selector 15:0 928 .byte 0 # 0 for interrupt gate 929 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 930 .word 0 # offset 31:16 931 .long 0 # offset 63:32 932 .long 0 # 0 for reserved 933 934# IRQ 1 (8042 Keyboard controller) - (INT 69h) 935.equ IRQ1_SEL, .-IDT_BASE 936 .word 0 # offset 15:0 937 .long SYS_CODE64_SEL # selector 15:0 938 .byte 0 # 0 for interrupt gate 939 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 940 .word 0 # offset 31:16 941 .long 0 # offset 63:32 942 .long 0 # 0 for reserved 943 944# Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah) 945.equ IRQ2_SEL, .-IDT_BASE 946 .word 0 # offset 15:0 947 .long SYS_CODE64_SEL # selector 15:0 948 .byte 0 # 0 for interrupt gate 949 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 950 .word 0 # offset 31:16 951 .long 0 # offset 63:32 952 .long 0 # 0 for reserved 953 954# IRQ 3 (COM 2) - (INT 6bh) 955.equ IRQ3_SEL, .-IDT_BASE 956 .word 0 # offset 15:0 957 .long SYS_CODE64_SEL # selector 15:0 958 .byte 0 # 0 for interrupt gate 959 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 960 .word 0 # offset 31:16 961 .long 0 # offset 63:32 962 .long 0 # 0 for reserved 963 964# IRQ 4 (COM 1) - (INT 6ch) 965.equ IRQ4_SEL, .-IDT_BASE 966 .word 0 # offset 15:0 967 .long SYS_CODE64_SEL # selector 15:0 968 .byte 0 # 0 for interrupt gate 969 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 970 .word 0 # offset 31:16 971 .long 0 # offset 63:32 972 .long 0 # 0 for reserved 973 974# IRQ 5 (LPT 2) - (INT 6dh) 975.equ IRQ5_SEL, .-IDT_BASE 976 .word 0 # offset 15:0 977 .long SYS_CODE64_SEL # selector 15:0 978 .byte 0 # 0 for interrupt gate 979 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 980 .word 0 # offset 31:16 981 .long 0 # offset 63:32 982 .long 0 # 0 for reserved 983 984# IRQ 6 (Floppy controller) - (INT 6eh) 985.equ IRQ6_SEL, .-IDT_BASE 986 .word 0 # offset 15:0 987 .long SYS_CODE64_SEL # selector 15:0 988 .byte 0 # 0 for interrupt gate 989 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 990 .word 0 # offset 31:16 991 .long 0 # offset 63:32 992 .long 0 # 0 for reserved 993 994# IRQ 7 (LPT 1) - (INT 6fh) 995.equ IRQ7_SEL, .-IDT_BASE 996 .word 0 # offset 15:0 997 .long SYS_CODE64_SEL # selector 15:0 998 .byte 0 # 0 for interrupt gate 999 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1000 .word 0 # offset 31:16 1001 .long 0 # offset 63:32 1002 .long 0 # 0 for reserved 1003 1004# IRQ 8 (RTC Alarm) - (INT 70h) 1005.equ IRQ8_SEL, .-IDT_BASE 1006 .word 0 # offset 15:0 1007 .long SYS_CODE64_SEL # selector 15:0 1008 .byte 0 # 0 for interrupt gate 1009 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1010 .word 0 # offset 31:16 1011 .long 0 # offset 63:32 1012 .long 0 # 0 for reserved 1013 1014# IRQ 9 - (INT 71h) 1015.equ IRQ9_SEL, .-IDT_BASE 1016 .word 0 # offset 15:0 1017 .long SYS_CODE64_SEL # selector 15:0 1018 .byte 0 # 0 for interrupt gate 1019 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1020 .word 0 # offset 31:16 1021 .long 0 # offset 63:32 1022 .long 0 # 0 for reserved 1023 1024# IRQ 10 - (INT 72h) 1025.equ IRQ10_SEL, .-IDT_BASE 1026 .word 0 # offset 15:0 1027 .long SYS_CODE64_SEL # selector 15:0 1028 .byte 0 # 0 for interrupt gate 1029 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1030 .word 0 # offset 31:16 1031 .long 0 # offset 63:32 1032 .long 0 # 0 for reserved 1033 1034# IRQ 11 - (INT 73h) 1035.equ IRQ11_SEL, .-IDT_BASE 1036 .word 0 # offset 15:0 1037 .long SYS_CODE64_SEL # selector 15:0 1038 .byte 0 # 0 for interrupt gate 1039 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1040 .word 0 # offset 31:16 1041 .long 0 # offset 63:32 1042 .long 0 # 0 for reserved 1043 1044# IRQ 12 (PS/2 mouse) - (INT 74h) 1045.equ IRQ12_SEL, .-IDT_BASE 1046 .word 0 # offset 15:0 1047 .long SYS_CODE64_SEL # selector 15:0 1048 .byte 0 # 0 for interrupt gate 1049 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1050 .word 0 # offset 31:16 1051 .long 0 # offset 63:32 1052 .long 0 # 0 for reserved 1053 1054# IRQ 13 (Floating point error) - (INT 75h) 1055.equ IRQ13_SEL, .-IDT_BASE 1056 .word 0 # offset 15:0 1057 .long SYS_CODE64_SEL # selector 15:0 1058 .byte 0 # 0 for interrupt gate 1059 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1060 .word 0 # offset 31:16 1061 .long 0 # offset 63:32 1062 .long 0 # 0 for reserved 1063 1064# IRQ 14 (Secondary IDE) - (INT 76h) 1065.equ IRQ14_SEL, .-IDT_BASE 1066 .word 0 # offset 15:0 1067 .long SYS_CODE64_SEL # selector 15:0 1068 .byte 0 # 0 for interrupt gate 1069 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1070 .word 0 # offset 31:16 1071 .long 0 # offset 63:32 1072 .long 0 # 0 for reserved 1073 1074# IRQ 15 (Primary IDE) - (INT 77h) 1075.equ IRQ15_SEL, .-IDT_BASE 1076 .word 0 # offset 15:0 1077 .long SYS_CODE64_SEL # selector 15:0 1078 .byte 0 # 0 for interrupt gate 1079 .byte 0x0e | 0x80 # type = 386 interrupt gate, present 1080 .word 0 # offset 31:16 1081 .long 0 # offset 63:32 1082 .long 0 # 0 for reserved 1083 1084IDT_END: 1085 1086 .p2align 1 1087 1088MemoryMapSize: .long 0 1089MemoryMap: .long 0,0,0,0,0,0,0,0 1090 .long 0,0,0,0,0,0,0,0 1091 .long 0,0,0,0,0,0,0,0 1092 .long 0,0,0,0,0,0,0,0 1093 .long 0,0,0,0,0,0,0,0 1094 .long 0,0,0,0,0,0,0,0 1095 .long 0,0,0,0,0,0,0,0 1096 .long 0,0,0,0,0,0,0,0 1097 .long 0,0,0,0,0,0,0,0 1098 .long 0,0,0,0,0,0,0,0 1099 .long 0,0,0,0,0,0,0,0 1100 .long 0,0,0,0,0,0,0,0 1101 .long 0,0,0,0,0,0,0,0 1102 .long 0,0,0,0,0,0,0,0 1103 .long 0,0,0,0,0,0,0,0 1104 .long 0,0,0,0,0,0,0,0 1105 .long 0,0,0,0,0,0,0,0 1106 .long 0,0,0,0,0,0,0,0 1107 .long 0,0,0,0,0,0,0,0 1108 .long 0,0,0,0,0,0,0,0 1109 .long 0,0,0,0,0,0,0,0 1110 .long 0,0,0,0,0,0,0,0 1111 .long 0,0,0,0,0,0,0,0 1112 .long 0,0,0,0,0,0,0,0 1113 .long 0,0,0,0,0,0,0,0 1114 .long 0,0,0,0,0,0,0,0 1115 .long 0,0,0,0,0,0,0,0 1116 .long 0,0,0,0,0,0,0,0 1117 .long 0,0,0,0,0,0,0,0 1118 .long 0,0,0,0,0,0,0,0 1119 1120 .long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 1121 1122 .org 0x0fe0 1123MyStack: 1124 # below is the pieces of the IVT that is used to redirect INT 68h - 6fh 1125 # back to INT 08h - 0fh when in real mode... It is 'org'ed to a 1126 # known low address (20f00) so it can be set up by PlMapIrqToVect in 1127 # 8259.c 1128 1129 int $8 1130 iret 1131 1132 int $9 1133 iret 1134 1135 int $10 1136 iret 1137 1138 int $11 1139 iret 1140 1141 int $12 1142 iret 1143 1144 int $13 1145 iret 1146 1147 int $14 1148 iret 1149 1150 int $15 1151 iret 1152 1153 1154 .org 0x0ffe 1155BlockSignature: 1156 .word 0xaa55 1157 1158