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gerrit.devboardsforandroid.linaro.org / device / linaro / hikey960 / 0e33772df9ca72fb5f6e3d9a9b9ee547997b1b66 / . / uefi / linaro-edk2 / DuetPkg / BootSector / start32.asm
blob: aaf04b86bc6b60499bd3f599914e60203de0bb95 [file] [log] [blame]
Vishal Bhoj82c80712015-12-15 21:13:33 +0530[diff] [blame]1;------------------------------------------------------------------------------
2;*
3;* Copyright (c) 2006 - 2011, 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;* start32.asm
13;*
14;* Abstract:
15;*
16;------------------------------------------------------------------------------
17
18 .model small
19 .stack
20 .486p
21 .code
22
23FAT_DIRECTORY_ENTRY_SIZE EQU 020h
24FAT_DIRECTORY_ENTRY_SHIFT EQU 5
25BLOCK_SIZE EQU 0200h
26BLOCK_MASK EQU 01ffh
27BLOCK_SHIFT EQU 9
28
29 org 0h
30Ia32Jump:
31 jmp BootSectorEntryPoint ; JMP inst - 3 bytes
32 nop
33
34OemId db "INTEL " ; OemId - 8 bytes
35SectorSize dw 0 ; Sector Size - 2 bytes
36SectorsPerCluster db 0 ; Sector Per Cluster - 1 byte
37ReservedSectors dw 0 ; Reserved Sectors - 2 bytes
38NoFats db 0 ; Number of FATs - 1 byte
39RootEntries dw 0 ; Root Entries - 2 bytes
40Sectors dw 0 ; Number of Sectors - 2 bytes
41Media db 0 ; Media - 1 byte
42SectorsPerFat16 dw 0 ; Sectors Per FAT for FAT12/FAT16 - 2 byte
43SectorsPerTrack dw 0 ; Sectors Per Track - 2 bytes
44Heads dw 0 ; Heads - 2 bytes
45HiddenSectors dd 0 ; Hidden Sectors - 4 bytes
46LargeSectors dd 0 ; Large Sectors - 4 bytes
47
48;******************************************************************************
49;
50;The structure for FAT32 starting at offset 36 of the boot sector. (At this point,
51;the BPB/boot sector for FAT12 and FAT16 differs from the BPB/boot sector for FAT32.)
52;
53;******************************************************************************
54
55SectorsPerFat32 dd 0 ; Sectors Per FAT for FAT32 - 4 bytes
56ExtFlags dw 0 ; Mirror Flag - 2 bytes
57FSVersion dw 0 ; File System Version - 2 bytes
58RootCluster dd 0 ; 1st Cluster Number of Root Dir - 4 bytes
59FSInfo dw 0 ; Sector Number of FSINFO - 2 bytes
60BkBootSector dw 0 ; Sector Number of Bk BootSector - 2 bytes
61Reserved db 12 dup(0) ; Reserved Field - 12 bytes
62PhysicalDrive db 0 ; Physical Drive Number - 1 byte
63Reserved1 db 0 ; Reserved Field - 1 byte
64Signature db 0 ; Extended Boot Signature - 1 byte
65VolId db " " ; Volume Serial Number - 4 bytes
66FatLabel db " " ; Volume Label - 11 bytes
67FileSystemType db "FAT32 " ; File System Type - 8 bytes
68
69BootSectorEntryPoint:
70 ASSUME ds:@code
71 ASSUME ss:@code
72 ; ds = 1000, es = 2000 + x (size of first cluster >> 4)
73 ; cx = Start Cluster of EfiLdr
74 ; dx = Start Cluster of Efivar.bin
75
76; Re use the BPB data stored in Boot Sector
77 mov bp,07c00h
78
79
80 push cx
81; Read Efivar.bin
82; 1000:dx = DirectoryEntry of Efivar.bin -> BS.com has filled already
83 mov ax,01900h
84 mov es,ax
85 test dx,dx
86 jnz CheckVarStoreSize
87
88 mov al,1
89NoVarStore:
90 push es
91; Set the 5th byte start @ 0:19000 to non-zero indicating we should init var store header in DxeIpl
92 mov byte ptr es:[4],al
93 jmp SaveVolumeId
94
95CheckVarStoreSize:
96 mov di,dx
97 cmp dword ptr ds:[di+2], 04000h
98 mov al,2
99 jne NoVarStore
100
101LoadVarStore:
102 mov al,0
103 mov byte ptr es:[4],al
104 mov cx,word ptr[di]
105; ES:DI = 1500:0
106 xor di,di
107 push es
108 mov ax,01500h
109 mov es,ax
110 call ReadFile
111SaveVolumeId:
112 pop es
113 mov ax,word ptr [bp+VolId]
114 mov word ptr es:[0],ax ; Save Volume Id to 0:19000. we will find the correct volume according to this VolumeId
115 mov ax,word ptr [bp+VolId+2]
116 mov word ptr es:[2],ax
117
118; Read Efildr
119 pop cx
120; cx = Start Cluster of Efildr -> BS.com has filled already
121; ES:DI = 2000:0, first cluster will be read again
122 xor di,di ; di = 0
123 mov ax,02000h
124 mov es,ax
125 call ReadFile
126 mov ax,cs
127 mov word ptr cs:[JumpSegment],ax
128JumpFarInstruction:
129 db 0eah
130JumpOffset:
131 dw 0200h
132JumpSegment:
133 dw 2000h
134
135
136
137
138; ****************************************************************************
139; ReadFile
140;
141; Arguments:
142; CX = Start Cluster of File
143; ES:DI = Buffer to store file content read from disk
144;
145; Return:
146; (ES << 4 + DI) = end of file content Buffer
147;
148; ****************************************************************************
149ReadFile:
150; si = NumberOfClusters
151; cx = ClusterNumber
152; dx = CachedFatSectorNumber
153; ds:0000 = CacheFatSectorBuffer
154; es:di = Buffer to load file
155; bx = NextClusterNumber
156 pusha
157 mov si,1 ; NumberOfClusters = 1
158 push cx ; Push Start Cluster onto stack
159 mov dx,0fffh ; CachedFatSectorNumber = 0xfff
160FatChainLoop:
161 mov ax,cx ; ax = ClusterNumber
162 and ax,0fff8h ; ax = ax & 0xfff8
163 cmp ax,0fff8h ; See if this is the last cluster
164 je FoundLastCluster ; Jump if last cluster found
165 mov ax,cx ; ax = ClusterNumber
166 shl ax,2 ; FatOffset = ClusterNumber * 4
167 push si ; Save si
168 mov si,ax ; si = FatOffset
169 shr ax,BLOCK_SHIFT ; ax = FatOffset >> BLOCK_SHIFT
170 add ax,word ptr [bp+ReservedSectors] ; ax = FatSectorNumber = ReservedSectors + (FatOffset >> BLOCK_OFFSET)
171 and si,BLOCK_MASK ; si = FatOffset & BLOCK_MASK
172 cmp ax,dx ; Compare FatSectorNumber to CachedFatSectorNumber
173 je SkipFatRead
174 mov bx,2
175 push es
176 push ds
177 pop es
178 call ReadBlocks ; Read 2 blocks starting at AX storing at ES:DI
179 pop es
180 mov dx,ax ; CachedFatSectorNumber = FatSectorNumber
181SkipFatRead:
182 mov bx,word ptr [si] ; bx = NextClusterNumber
183 mov ax,cx ; ax = ClusterNumber
184 pop si ; Restore si
185 dec bx ; bx = NextClusterNumber - 1
186 cmp bx,cx ; See if (NextClusterNumber-1)==ClusterNumber
187 jne ReadClusters
188 inc bx ; bx = NextClusterNumber
189 inc si ; NumberOfClusters++
190 mov cx,bx ; ClusterNumber = NextClusterNumber
191 jmp FatChainLoop
192ReadClusters:
193 inc bx
194 pop ax ; ax = StartCluster
195 push bx ; StartCluster = NextClusterNumber
196 mov cx,bx ; ClusterNumber = NextClusterNumber
197 sub ax,2 ; ax = StartCluster - 2
198 xor bh,bh
199 mov bl,byte ptr [bp+SectorsPerCluster] ; bx = SectorsPerCluster
200 mul bx ; ax = (StartCluster - 2) * SectorsPerCluster
201 add ax, word ptr [bp] ; ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster
202 push ax ; save start sector
203 mov ax,si ; ax = NumberOfClusters
204 mul bx ; ax = NumberOfClusters * SectorsPerCluster
205 mov bx,ax ; bx = Number of Sectors
206 pop ax ; ax = Start Sector
207 call ReadBlocks
208 mov si,1 ; NumberOfClusters = 1
209 jmp FatChainLoop
210FoundLastCluster:
211 pop cx
212 popa
213 ret
214
215
216; ****************************************************************************
217; ReadBlocks - Reads a set of blocks from a block device
218;
219; AX = Start LBA
220; BX = Number of Blocks to Read
221; ES:DI = Buffer to store sectors read from disk
222; ****************************************************************************
223
224; cx = Blocks
225; bx = NumberOfBlocks
226; si = StartLBA
227
228ReadBlocks:
229 pusha
230 add eax,dword ptr [bp+LBAOffsetForBootSector] ; Add LBAOffsetForBootSector to Start LBA
231 add eax,dword ptr [bp+HiddenSectors] ; Add HiddenSectors to Start LBA
232 mov esi,eax ; esi = Start LBA
233 mov cx,bx ; cx = Number of blocks to read
234ReadCylinderLoop:
235 mov bp,07bfch ; bp = 0x7bfc
236 mov eax,esi ; eax = Start LBA
237 xor edx,edx ; edx = 0
238 movzx ebx,word ptr [bp] ; bx = MaxSector
239 div ebx ; ax = StartLBA / MaxSector
240 inc dx ; dx = (StartLBA % MaxSector) + 1
241
242 mov bx,word ptr [bp] ; bx = MaxSector
243 sub bx,dx ; bx = MaxSector - Sector
244 inc bx ; bx = MaxSector - Sector + 1
245 cmp cx,bx ; Compare (Blocks) to (MaxSector - Sector + 1)
246 jg LimitTransfer
247 mov bx,cx ; bx = Blocks
248LimitTransfer:
249 push ax ; save ax
250 mov ax,es ; ax = es
251 shr ax,(BLOCK_SHIFT-4) ; ax = Number of blocks into mem system
252 and ax,07fh ; ax = Number of blocks into current seg
253 add ax,bx ; ax = End Block number of transfer
254 cmp ax,080h ; See if it crosses a 64K boundry
255 jle NotCrossing64KBoundry ; Branch if not crossing 64K boundry
256 sub ax,080h ; ax = Number of blocks past 64K boundry
257 sub bx,ax ; Decrease transfer size by block overage
258NotCrossing64KBoundry:
259 pop ax ; restore ax
260
261 push cx
262 mov cl,dl ; cl = (StartLBA % MaxSector) + 1 = Sector
263 xor dx,dx ; dx = 0
264 div word ptr [bp+2] ; ax = ax / (MaxHead + 1) = Cylinder
265 ; dx = ax % (MaxHead + 1) = Head
266
267 push bx ; Save number of blocks to transfer
268 mov dh,dl ; dh = Head
269 mov bp,07c00h ; bp = 0x7c00
270 mov dl,byte ptr [bp+PhysicalDrive] ; dl = Drive Number
271 mov ch,al ; ch = Cylinder
272 mov al,bl ; al = Blocks
273 mov ah,2 ; ah = Function 2
274 mov bx,di ; es:bx = Buffer address
275 int 013h
276 jc DiskError
277 pop bx
278 pop cx
279 movzx ebx,bx
280 add esi,ebx ; StartLBA = StartLBA + NumberOfBlocks
281 sub cx,bx ; Blocks = Blocks - NumberOfBlocks
282 mov ax,es
283 shl bx,(BLOCK_SHIFT-4)
284 add ax,bx
285 mov es,ax ; es:di = es:di + NumberOfBlocks*BLOCK_SIZE
286 cmp cx,0
287 jne ReadCylinderLoop
288 popa
289 ret
290
291DiskError:
292 push cs
293 pop ds
294 lea si, [ErrorString]
295 mov cx, 7
296 jmp PrintStringAndHalt
297
298PrintStringAndHalt:
299 mov ax,0b800h
300 mov es,ax
301 mov di,160
302 rep movsw
303Halt:
304 jmp Halt
305
306ErrorString:
307 db 'S', 0ch, 'E', 0ch, 'r', 0ch, 'r', 0ch, 'o', 0ch, 'r', 0ch, '!', 0ch
308
309 org 01fah
310LBAOffsetForBootSector:
311 dd 0h
312
313 org 01feh
314 dw 0aa55h
315
316;******************************************************************************
317;******************************************************************************
318;******************************************************************************
319
320DELAY_PORT equ 0edh ; Port to use for 1uS delay
321KBD_CONTROL_PORT equ 060h ; 8042 control port
322KBD_STATUS_PORT equ 064h ; 8042 status port
323WRITE_DATA_PORT_CMD equ 0d1h ; 8042 command to write the data port
324ENABLE_A20_CMD equ 0dfh ; 8042 command to enable A20
325
326 org 200h
327 jmp start
328Em64String:
329 db 'E', 0ch, 'm', 0ch, '6', 0ch, '4', 0ch, 'T', 0ch, ' ', 0ch, 'U', 0ch, 'n', 0ch, 's', 0ch, 'u', 0ch, 'p', 0ch, 'p', 0ch, 'o', 0ch, 'r', 0ch, 't', 0ch, 'e', 0ch, 'd', 0ch, '!', 0ch
330
331start:
332 mov ax,cs
333 mov ds,ax
334 mov es,ax
335 mov ss,ax
336 mov sp,MyStack
337
338; mov ax,0b800h
339; mov es,ax
340; mov byte ptr es:[160],'a'
341; mov ax,cs
342; mov es,ax
343
344 mov ebx,0
345 lea edi,MemoryMap
346MemMapLoop:
347 mov eax,0e820h
348 mov ecx,20
349 mov edx,'SMAP'
350 int 15h
351 jc MemMapDone
352 add edi,20
353 cmp ebx,0
354 je MemMapDone
355 jmp MemMapLoop
356MemMapDone:
357 lea eax,MemoryMap
358 sub edi,eax ; Get the address of the memory map
359 mov dword ptr [MemoryMapSize],edi ; Save the size of the memory map
360
361 xor ebx,ebx
362 mov bx,cs ; BX=segment
363 shl ebx,4 ; BX="linear" address of segment base
364 lea eax,[GDT_BASE + ebx] ; EAX=PHYSICAL address of gdt
365 mov dword ptr [gdtr + 2],eax ; Put address of gdt into the gdtr
366 lea eax,[IDT_BASE + ebx] ; EAX=PHYSICAL address of idt
367 mov dword ptr [idtr + 2],eax ; Put address of idt into the idtr
368 lea edx,[MemoryMapSize + ebx] ; Physical base address of the memory map
369
370 add ebx,01000h ; Source of EFI32
371 mov dword ptr [JUMP+2],ebx
372 add ebx,01000h
373 mov esi,ebx ; Source of EFILDR32
374
375; mov ax,0b800h
376; mov es,ax
377; mov byte ptr es:[162],'b'
378; mov ax,cs
379; mov es,ax
380
381;
382; Enable A20 Gate
383;
384
385 mov ax,2401h ; Enable A20 Gate
386 int 15h
387 jnc A20GateEnabled ; Jump if it suceeded
388
389;
390; If INT 15 Function 2401 is not supported, then attempt to Enable A20 manually.
391;
392
393 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
394 jnz Timeout8042 ; Jump if the 8042 timed out
395 out DELAY_PORT,ax ; Delay 1 uS
396 mov al,WRITE_DATA_PORT_CMD ; 8042 cmd to write output port
397 out KBD_STATUS_PORT,al ; Send command to the 8042
398 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
399 jnz Timeout8042 ; Jump if the 8042 timed out
400 mov al,ENABLE_A20_CMD ; gate address bit 20 on
401 out KBD_CONTROL_PORT,al ; Send command to thre 8042
402 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
403 mov cx,25 ; Delay 25 uS for the command to complete on the 8042
404Delay25uS:
405 out DELAY_PORT,ax ; Delay 1 uS
406 loop Delay25uS
407Timeout8042:
408
409
410A20GateEnabled:
411 mov bx,0008h ; Flat data descriptor
412;
413; DISABLE INTERRUPTS - Entering Protected Mode
414;
415
416 cli
417
418; mov ax,0b800h
419; mov es,ax
420; mov byte ptr es:[164],'c'
421; mov ax,cs
422; mov es,ax
423
424 db 66h
425 lgdt fword ptr [gdtr]
426 db 66h
427 lidt fword ptr [idtr]
428
429 mov eax,cr0
430 or al,1
431 mov cr0,eax
432JUMP:
433; jmp far 0010:00020000
434 db 066h
435 db 0eah
436 dd 000020000h
437 dw 00010h
438
439Empty8042InputBuffer:
440 mov cx,0
441Empty8042Loop:
442 out DELAY_PORT,ax ; Delay 1us
443 in al,KBD_STATUS_PORT ; Read the 8042 Status Port
444 and al,02h ; Check the Input Buffer Full Flag
445 loopnz Empty8042Loop ; Loop until the input buffer is empty or a timout of 65536 uS
446 ret
447
448;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
449; data
450;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
451
452 align 02h
453
454gdtr dw GDT_END - GDT_BASE - 1 ; GDT limit
455 dd 0 ; (GDT base gets set above)
456;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
457; global descriptor table (GDT)
458;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
459
460 align 02h
461
462public GDT_BASE
463GDT_BASE:
464; null descriptor
465NULL_SEL equ $-GDT_BASE
466 dw 0 ; limit 15:0
467 dw 0 ; base 15:0
468 db 0 ; base 23:16
469 db 0 ; type
470 db 0 ; limit 19:16, flags
471 db 0 ; base 31:24
472
473; linear data segment descriptor
474LINEAR_SEL equ $-GDT_BASE
475 dw 0FFFFh ; limit 0xFFFFF
476 dw 0 ; base 0
477 db 0
478 db 092h ; present, ring 0, data, expand-up, writable
479 db 0CFh ; page-granular, 32-bit
480 db 0
481
482; linear code segment descriptor
483LINEAR_CODE_SEL equ $-GDT_BASE
484 dw 0FFFFh ; limit 0xFFFFF
485 dw 0 ; base 0
486 db 0
487 db 09Ah ; present, ring 0, data, expand-up, writable
488 db 0CFh ; page-granular, 32-bit
489 db 0
490
491; system data segment descriptor
492SYS_DATA_SEL equ $-GDT_BASE
493 dw 0FFFFh ; limit 0xFFFFF
494 dw 0 ; base 0
495 db 0
496 db 092h ; present, ring 0, data, expand-up, writable
497 db 0CFh ; page-granular, 32-bit
498 db 0
499
500; system code segment descriptor
501SYS_CODE_SEL equ $-GDT_BASE
502 dw 0FFFFh ; limit 0xFFFFF
503 dw 0 ; base 0
504 db 0
505 db 09Ah ; present, ring 0, data, expand-up, writable
506 db 0CFh ; page-granular, 32-bit
507 db 0
508
509; spare segment descriptor
510SPARE3_SEL equ $-GDT_BASE
511 dw 0 ; limit 0xFFFFF
512 dw 0 ; base 0
513 db 0
514 db 0 ; present, ring 0, data, expand-up, writable
515 db 0 ; page-granular, 32-bit
516 db 0
517
518; spare segment descriptor
519SPARE4_SEL equ $-GDT_BASE
520 dw 0 ; limit 0xFFFFF
521 dw 0 ; base 0
522 db 0
523 db 0 ; present, ring 0, data, expand-up, writable
524 db 0 ; page-granular, 32-bit
525 db 0
526
527; spare segment descriptor
528SPARE5_SEL equ $-GDT_BASE
529 dw 0 ; limit 0xFFFFF
530 dw 0 ; base 0
531 db 0
532 db 0 ; present, ring 0, data, expand-up, writable
533 db 0 ; page-granular, 32-bit
534 db 0
535
536GDT_END:
537
538 align 02h
539
540
541
542idtr dw IDT_END - IDT_BASE - 1 ; IDT limit
543 dd 0 ; (IDT base gets set above)
544;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
545; interrupt descriptor table (IDT)
546;
547; Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ
548; mappings. This implementation only uses the system timer and all other
549; IRQs will remain masked. The descriptors for vectors 33+ are provided
550; for convenience.
551;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
552
553;idt_tag db "IDT",0
554 align 02h
555
556public IDT_BASE
557IDT_BASE:
558; divide by zero (INT 0)
559DIV_ZERO_SEL equ $-IDT_BASE
560 dw 0 ; offset 15:0
561 dw SYS_CODE_SEL ; selector 15:0
562 db 0 ; 0 for interrupt gate
563 db 0eh OR 80h ; type = 386 interrupt gate, present
564 dw 0 ; offset 31:16
565
566; debug exception (INT 1)
567DEBUG_EXCEPT_SEL equ $-IDT_BASE
568 dw 0 ; offset 15:0
569 dw SYS_CODE_SEL ; selector 15:0
570 db 0 ; 0 for interrupt gate
571 db 0eh OR 80h ; type = 386 interrupt gate, present
572 dw 0 ; offset 31:16
573
574; NMI (INT 2)
575NMI_SEL equ $-IDT_BASE
576 dw 0 ; offset 15:0
577 dw SYS_CODE_SEL ; selector 15:0
578 db 0 ; 0 for interrupt gate
579 db 0eh OR 80h ; type = 386 interrupt gate, present
580 dw 0 ; offset 31:16
581
582; soft breakpoint (INT 3)
583BREAKPOINT_SEL equ $-IDT_BASE
584 dw 0 ; offset 15:0
585 dw SYS_CODE_SEL ; selector 15:0
586 db 0 ; 0 for interrupt gate
587 db 0eh OR 80h ; type = 386 interrupt gate, present
588 dw 0 ; offset 31:16
589
590; overflow (INT 4)
591OVERFLOW_SEL equ $-IDT_BASE
592 dw 0 ; offset 15:0
593 dw SYS_CODE_SEL ; selector 15:0
594 db 0 ; 0 for interrupt gate
595 db 0eh OR 80h ; type = 386 interrupt gate, present
596 dw 0 ; offset 31:16
597
598; bounds check (INT 5)
599BOUNDS_CHECK_SEL equ $-IDT_BASE
600 dw 0 ; offset 15:0
601 dw SYS_CODE_SEL ; selector 15:0
602 db 0 ; 0 for interrupt gate
603 db 0eh OR 80h ; type = 386 interrupt gate, present
604 dw 0 ; offset 31:16
605
606; invalid opcode (INT 6)
607INVALID_OPCODE_SEL equ $-IDT_BASE
608 dw 0 ; offset 15:0
609 dw SYS_CODE_SEL ; selector 15:0
610 db 0 ; 0 for interrupt gate
611 db 0eh OR 80h ; type = 386 interrupt gate, present
612 dw 0 ; offset 31:16
613
614; device not available (INT 7)
615DEV_NOT_AVAIL_SEL equ $-IDT_BASE
616 dw 0 ; offset 15:0
617 dw SYS_CODE_SEL ; selector 15:0
618 db 0 ; 0 for interrupt gate
619 db 0eh OR 80h ; type = 386 interrupt gate, present
620 dw 0 ; offset 31:16
621
622; double fault (INT 8)
623DOUBLE_FAULT_SEL equ $-IDT_BASE
624 dw 0 ; offset 15:0
625 dw SYS_CODE_SEL ; selector 15:0
626 db 0 ; 0 for interrupt gate
627 db 0eh OR 80h ; type = 386 interrupt gate, present
628 dw 0 ; offset 31:16
629
630; Coprocessor segment overrun - reserved (INT 9)
631RSVD_INTR_SEL1 equ $-IDT_BASE
632 dw 0 ; offset 15:0
633 dw SYS_CODE_SEL ; selector 15:0
634 db 0 ; 0 for interrupt gate
635 db 0eh OR 80h ; type = 386 interrupt gate, present
636 dw 0 ; offset 31:16
637
638; invalid TSS (INT 0ah)
639INVALID_TSS_SEL equ $-IDT_BASE
640 dw 0 ; offset 15:0
641 dw SYS_CODE_SEL ; selector 15:0
642 db 0 ; 0 for interrupt gate
643 db 0eh OR 80h ; type = 386 interrupt gate, present
644 dw 0 ; offset 31:16
645
646; segment not present (INT 0bh)
647SEG_NOT_PRESENT_SEL equ $-IDT_BASE
648 dw 0 ; offset 15:0
649 dw SYS_CODE_SEL ; selector 15:0
650 db 0 ; 0 for interrupt gate
651 db 0eh OR 80h ; type = 386 interrupt gate, present
652 dw 0 ; offset 31:16
653
654; stack fault (INT 0ch)
655STACK_FAULT_SEL equ $-IDT_BASE
656 dw 0 ; offset 15:0
657 dw SYS_CODE_SEL ; selector 15:0
658 db 0 ; 0 for interrupt gate
659 db 0eh OR 80h ; type = 386 interrupt gate, present
660 dw 0 ; offset 31:16
661
662; general protection (INT 0dh)
663GP_FAULT_SEL equ $-IDT_BASE
664 dw 0 ; offset 15:0
665 dw SYS_CODE_SEL ; selector 15:0
666 db 0 ; 0 for interrupt gate
667 db 0eh OR 80h ; type = 386 interrupt gate, present
668 dw 0 ; offset 31:16
669
670; page fault (INT 0eh)
671PAGE_FAULT_SEL equ $-IDT_BASE
672 dw 0 ; offset 15:0
673 dw SYS_CODE_SEL ; selector 15:0
674 db 0 ; 0 for interrupt gate
675 db 0eh OR 80h ; type = 386 interrupt gate, present
676 dw 0 ; offset 31:16
677
678; Intel reserved - do not use (INT 0fh)
679RSVD_INTR_SEL2 equ $-IDT_BASE
680 dw 0 ; offset 15:0
681 dw SYS_CODE_SEL ; selector 15:0
682 db 0 ; 0 for interrupt gate
683 db 0eh OR 80h ; type = 386 interrupt gate, present
684 dw 0 ; offset 31:16
685
686; floating point error (INT 10h)
687FLT_POINT_ERR_SEL equ $-IDT_BASE
688 dw 0 ; offset 15:0
689 dw SYS_CODE_SEL ; selector 15:0
690 db 0 ; 0 for interrupt gate
691 db 0eh OR 80h ; type = 386 interrupt gate, present
692 dw 0 ; offset 31:16
693
694; alignment check (INT 11h)
695ALIGNMENT_CHECK_SEL equ $-IDT_BASE
696 dw 0 ; offset 15:0
697 dw SYS_CODE_SEL ; selector 15:0
698 db 0 ; 0 for interrupt gate
699 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
700 dw 0 ; offset 31:16
701
702; machine check (INT 12h)
703MACHINE_CHECK_SEL equ $-IDT_BASE
704 dw 0 ; offset 15:0
705 dw SYS_CODE_SEL ; selector 15:0
706 db 0 ; 0 for interrupt gate
707 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
708 dw 0 ; offset 31:16
709
710; SIMD floating-point exception (INT 13h)
711SIMD_EXCEPTION_SEL equ $-IDT_BASE
712 dw 0 ; offset 15:0
713 dw SYS_CODE_SEL ; selector 15:0
714 db 0 ; 0 for interrupt gate
715 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
716 dw 0 ; offset 31:16
717
718; 85 unspecified descriptors, First 12 of them are reserved, the rest are avail
719 db (85 * 8) dup(0)
720
721; IRQ 0 (System timer) - (INT 68h)
722IRQ0_SEL equ $-IDT_BASE
723 dw 0 ; offset 15:0
724 dw SYS_CODE_SEL ; selector 15:0
725 db 0 ; 0 for interrupt gate
726 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
727 dw 0 ; offset 31:16
728
729; IRQ 1 (8042 Keyboard controller) - (INT 69h)
730IRQ1_SEL equ $-IDT_BASE
731 dw 0 ; offset 15:0
732 dw SYS_CODE_SEL ; selector 15:0
733 db 0 ; 0 for interrupt gate
734 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
735 dw 0 ; offset 31:16
736
737; Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah)
738IRQ2_SEL equ $-IDT_BASE
739 dw 0 ; offset 15:0
740 dw SYS_CODE_SEL ; selector 15:0
741 db 0 ; 0 for interrupt gate
742 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
743 dw 0 ; offset 31:16
744
745; IRQ 3 (COM 2) - (INT 6bh)
746IRQ3_SEL equ $-IDT_BASE
747 dw 0 ; offset 15:0
748 dw SYS_CODE_SEL ; selector 15:0
749 db 0 ; 0 for interrupt gate
750 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
751 dw 0 ; offset 31:16
752
753; IRQ 4 (COM 1) - (INT 6ch)
754IRQ4_SEL equ $-IDT_BASE
755 dw 0 ; offset 15:0
756 dw SYS_CODE_SEL ; selector 15:0
757 db 0 ; 0 for interrupt gate
758 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
759 dw 0 ; offset 31:16
760
761; IRQ 5 (LPT 2) - (INT 6dh)
762IRQ5_SEL equ $-IDT_BASE
763 dw 0 ; offset 15:0
764 dw SYS_CODE_SEL ; selector 15:0
765 db 0 ; 0 for interrupt gate
766 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
767 dw 0 ; offset 31:16
768
769; IRQ 6 (Floppy controller) - (INT 6eh)
770IRQ6_SEL equ $-IDT_BASE
771 dw 0 ; offset 15:0
772 dw SYS_CODE_SEL ; selector 15:0
773 db 0 ; 0 for interrupt gate
774 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
775 dw 0 ; offset 31:16
776
777; IRQ 7 (LPT 1) - (INT 6fh)
778IRQ7_SEL equ $-IDT_BASE
779 dw 0 ; offset 15:0
780 dw SYS_CODE_SEL ; selector 15:0
781 db 0 ; 0 for interrupt gate
782 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
783 dw 0 ; offset 31:16
784
785; IRQ 8 (RTC Alarm) - (INT 70h)
786IRQ8_SEL equ $-IDT_BASE
787 dw 0 ; offset 15:0
788 dw SYS_CODE_SEL ; selector 15:0
789 db 0 ; 0 for interrupt gate
790 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
791 dw 0 ; offset 31:16
792
793; IRQ 9 - (INT 71h)
794IRQ9_SEL equ $-IDT_BASE
795 dw 0 ; offset 15:0
796 dw SYS_CODE_SEL ; selector 15:0
797 db 0 ; 0 for interrupt gate
798 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
799 dw 0 ; offset 31:16
800
801; IRQ 10 - (INT 72h)
802IRQ10_SEL equ $-IDT_BASE
803 dw 0 ; offset 15:0
804 dw SYS_CODE_SEL ; selector 15:0
805 db 0 ; 0 for interrupt gate
806 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
807 dw 0 ; offset 31:16
808
809; IRQ 11 - (INT 73h)
810IRQ11_SEL equ $-IDT_BASE
811 dw 0 ; offset 15:0
812 dw SYS_CODE_SEL ; selector 15:0
813 db 0 ; 0 for interrupt gate
814 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
815 dw 0 ; offset 31:16
816
817; IRQ 12 (PS/2 mouse) - (INT 74h)
818IRQ12_SEL equ $-IDT_BASE
819 dw 0 ; offset 15:0
820 dw SYS_CODE_SEL ; selector 15:0
821 db 0 ; 0 for interrupt gate
822 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
823 dw 0 ; offset 31:16
824
825; IRQ 13 (Floating point error) - (INT 75h)
826IRQ13_SEL equ $-IDT_BASE
827 dw 0 ; offset 15:0
828 dw SYS_CODE_SEL ; selector 15:0
829 db 0 ; 0 for interrupt gate
830 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
831 dw 0 ; offset 31:16
832
833; IRQ 14 (Secondary IDE) - (INT 76h)
834IRQ14_SEL equ $-IDT_BASE
835 dw 0 ; offset 15:0
836 dw SYS_CODE_SEL ; selector 15:0
837 db 0 ; 0 for interrupt gate
838 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
839 dw 0 ; offset 31:16
840
841; IRQ 15 (Primary IDE) - (INT 77h)
842IRQ15_SEL equ $-IDT_BASE
843 dw 0 ; offset 15:0
844 dw SYS_CODE_SEL ; selector 15:0
845 db 0 ; 0 for interrupt gate
846 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
847 dw 0 ; offset 31:16
848
849IDT_END:
850
851 align 02h
852
853MemoryMapSize dd 0
854MemoryMap dd 0,0,0,0,0,0,0,0
855 dd 0,0,0,0,0,0,0,0
856 dd 0,0,0,0,0,0,0,0
857 dd 0,0,0,0,0,0,0,0
858 dd 0,0,0,0,0,0,0,0
859 dd 0,0,0,0,0,0,0,0
860 dd 0,0,0,0,0,0,0,0
861 dd 0,0,0,0,0,0,0,0
862 dd 0,0,0,0,0,0,0,0
863 dd 0,0,0,0,0,0,0,0
864 dd 0,0,0,0,0,0,0,0
865 dd 0,0,0,0,0,0,0,0
866 dd 0,0,0,0,0,0,0,0
867 dd 0,0,0,0,0,0,0,0
868 dd 0,0,0,0,0,0,0,0
869 dd 0,0,0,0,0,0,0,0
870 dd 0,0,0,0,0,0,0,0
871 dd 0,0,0,0,0,0,0,0
872 dd 0,0,0,0,0,0,0,0
873 dd 0,0,0,0,0,0,0,0
874 dd 0,0,0,0,0,0,0,0
875 dd 0,0,0,0,0,0,0,0
876 dd 0,0,0,0,0,0,0,0
877 dd 0,0,0,0,0,0,0,0
878 dd 0,0,0,0,0,0,0,0
879 dd 0,0,0,0,0,0,0,0
880 dd 0,0,0,0,0,0,0,0
881 dd 0,0,0,0,0,0,0,0
882 dd 0,0,0,0,0,0,0,0
883 dd 0,0,0,0,0,0,0,0
884
885 dd 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
886 dd 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
887
888 org 0fe0h
889MyStack:
890 ; below is the pieces of the IVT that is used to redirect INT 68h - 6fh
891 ; back to INT 08h - 0fh when in real mode... It is 'org'ed to a
892 ; known low address (20f00) so it can be set up by PlMapIrqToVect in
893 ; 8259.c
894
895 int 8
896 iret
897
898 int 9
899 iret
900
901 int 10
902 iret
903
904 int 11
905 iret
906
907 int 12
908 iret
909
910 int 13
911 iret
912
913 int 14
914 iret
915
916 int 15
917 iret
918
919
920 org 0ffeh
921BlockSignature:
922 dw 0aa55h
923
924 end