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Porting Duet module from EDKI to EDKII
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1 ;------------------------------------------------------------------------------
2 ;*
3 ;* Copyright 2006 - 2007, Intel Corporation
4 ;* All rights reserved. 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 ;* start.asm
13 ;*
14 ;* Abstract:
15 ;*
16 ;------------------------------------------------------------------------------
17
18 .model small
19 .stack
20 .486p
21 .code
22
23 FAT_DIRECTORY_ENTRY_SIZE EQU 020h
24 FAT_DIRECTORY_ENTRY_SHIFT EQU 5
25 BLOCK_SIZE EQU 0200h
26 BLOCK_MASK EQU 01ffh
27 BLOCK_SHIFT EQU 9
28
29 org 0h
30 Ia32Jump:
31 jmp BootSectorEntryPoint ; JMP inst - 3 bytes
32 nop
33
34 OemId db "INTEL " ; OemId - 8 bytes
35
36 SectorSize dw 0 ; Sector Size - 16 bits
37 SectorsPerCluster db 0 ; Sector Per Cluster - 8 bits
38 ReservedSectors dw 0 ; Reserved Sectors - 16 bits
39 NoFats db 0 ; Number of FATs - 8 bits
40 RootEntries dw 0 ; Root Entries - 16 bits
41 Sectors dw 0 ; Number of Sectors - 16 bits
42 Media db 0 ; Media - 8 bits - ignored
43 SectorsPerFat dw 0 ; Sectors Per FAT - 16 bits
44 SectorsPerTrack dw 0 ; Sectors Per Track - 16 bits - ignored
45 Heads dw 0 ; Heads - 16 bits - ignored
46 HiddenSectors dd 0 ; Hidden Sectors - 32 bits - ignored
47 LargeSectors dd 0 ; Large Sectors - 32 bits
48 PhysicalDrive db 0 ; PhysicalDriveNumber - 8 bits - ignored
49 CurrentHead db 0 ; Current Head - 8 bits
50 Signature db 0 ; Signature - 8 bits - ignored
51 VolId db " " ; Volume Serial Number- 4 bytes
52 FatLabel db " " ; Label - 11 bytes
53 SystemId db "FAT12 " ; SystemId - 8 bytes
54
55 BootSectorEntryPoint:
56 ASSUME ds:@code
57 ASSUME ss:@code
58 ; ds = 1000, es = 2000 + x (size of first cluster >> 4)
59 ; cx = Start Cluster of EfiLdr
60 ; dx = Start Cluster of Efivar.bin
61
62 ; Re use the BPB data stored in Boot Sector
63 mov bp,07c00h
64
65 push cx
66 ; Read Efivar.bin
67 ; 1000:dx = DirectoryEntry of Efivar.bin -> BS.com has filled already
68 mov ax,01900h
69 mov es,ax
70 test dx,dx
71 jnz CheckVarStoreSize
72
73 mov al,1
74 NoVarStore:
75 push es
76 ; Set the 5th byte start @ 0:19000 to non-zero indicating we should init var store header in DxeIpl
77 mov byte ptr es:[4],al
78 jmp SaveVolumeId
79
80 CheckVarStoreSize:
81 mov di,dx
82 cmp dword ptr ds:[di+2], 04000h
83 mov al,2
84 jne NoVarStore
85
86 LoadVarStore:
87 mov al,0
88 mov byte ptr es:[4],al
89 mov cx,word ptr[di]
90 ; ES:DI = 1500:0
91 xor di,di
92 push es
93 mov ax,01500h
94 mov es,ax
95 call ReadFile
96 SaveVolumeId:
97 pop es
98 mov ax,word ptr [bp+VolId]
99 mov word ptr es:[0],ax ; Save Volume Id to 0:19000. we will find the correct volume according to this VolumeId
100 mov ax,word ptr [bp+VolId+2]
101 mov word ptr es:[2],ax
102
103 ; Read Efildr
104 pop cx
105 ; cx = Start Cluster of Efildr -> BS.com has filled already
106 ; ES:DI = 2000:0, first cluster will be read again
107 xor di,di ; di = 0
108 mov ax,02000h
109 mov es,ax
110 call ReadFile
111 mov ax,cs
112 mov word ptr cs:[JumpSegment],ax
113
114 JumpFarInstruction:
115 db 0eah
116 JumpOffset:
117 dw 0200h
118 JumpSegment:
119 dw 2000h
120
121
122
123 ; ****************************************************************************
124 ; ReadFile
125 ;
126 ; Arguments:
127 ; CX = Start Cluster of File
128 ; ES:DI = Buffer to store file content read from disk
129 ;
130 ; Return:
131 ; (ES << 4 + DI) = end of file content Buffer
132 ;
133 ; ****************************************************************************
134 ReadFile:
135 ; si = NumberOfClusters
136 ; cx = ClusterNumber
137 ; dx = CachedFatSectorNumber
138 ; ds:0000 = CacheFatSectorBuffer
139 ; es:di = Buffer to load file
140 ; bx = NextClusterNumber
141 pusha
142 mov si,1 ; NumberOfClusters = 1
143 push cx ; Push Start Cluster onto stack
144 mov dx,0fffh ; CachedFatSectorNumber = 0xfff
145 FatChainLoop:
146 mov ax,cx ; ax = ClusterNumber
147 and ax,0ff8h ; ax = ax & 0xff8
148 cmp ax,0ff8h ; See if this is the last cluster
149 je FoundLastCluster ; Jump if last cluster found
150 mov ax,cx ; ax = ClusterNumber
151 shl ax,1 ; ax = ClusterNumber * 2
152 add ax,cx ; ax = ClusterNumber * 2 + ClusterNumber = ClusterNumber * 3
153 shr ax,1 ; FatOffset = ClusterNumber*3 / 2
154 push si ; Save si
155 mov si,ax ; si = FatOffset
156 shr ax,BLOCK_SHIFT ; ax = FatOffset >> BLOCK_SHIFT
157 add ax,word ptr [bp+ReservedSectors] ; ax = FatSectorNumber = ReservedSectors + (FatOffset >> BLOCK_OFFSET)
158 and si,BLOCK_MASK ; si = FatOffset & BLOCK_MASK
159 cmp ax,dx ; Compare FatSectorNumber to CachedFatSectorNumber
160 je SkipFatRead
161 mov bx,2
162 push es
163 push ds
164 pop es
165 call ReadBlocks ; Read 2 blocks starting at AX storing at ES:DI
166 pop es
167 mov dx,ax ; CachedFatSectorNumber = FatSectorNumber
168 SkipFatRead:
169 mov bx,word ptr [si] ; bx = NextClusterNumber
170 mov ax,cx ; ax = ClusterNumber
171 and ax,1 ; See if this is an odd cluster number
172 je EvenFatEntry
173 shr bx,4 ; NextClusterNumber = NextClusterNumber >> 4
174 EvenFatEntry:
175 and bx,0fffh ; Strip upper 4 bits of NextClusterNumber
176 pop si ; Restore si
177 dec bx ; bx = NextClusterNumber - 1
178 cmp bx,cx ; See if (NextClusterNumber-1)==ClusterNumber
179 jne ReadClusters
180 inc bx ; bx = NextClusterNumber
181 inc si ; NumberOfClusters++
182 mov cx,bx ; ClusterNumber = NextClusterNumber
183 jmp FatChainLoop
184 ReadClusters:
185 inc bx
186 pop ax ; ax = StartCluster
187 push bx ; StartCluster = NextClusterNumber
188 mov cx,bx ; ClusterNumber = NextClusterNumber
189 sub ax,2 ; ax = StartCluster - 2
190 xor bh,bh
191 mov bl,byte ptr [bp+SectorsPerCluster] ; bx = SectorsPerCluster
192 mul bx ; ax = (StartCluster - 2) * SectorsPerCluster
193 add ax, word ptr [bp] ; ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster
194 push ax ; save start sector
195 mov ax,si ; ax = NumberOfClusters
196 mul bx ; ax = NumberOfClusters * SectorsPerCluster
197 mov bx,ax ; bx = Number of Sectors
198 pop ax ; ax = Start Sector
199 call ReadBlocks
200 mov si,1 ; NumberOfClusters = 1
201 jmp FatChainLoop
202 FoundLastCluster:
203 pop cx
204 popa
205 ret
206
207
208 ; ****************************************************************************
209 ; ReadBlocks - Reads a set of blocks from a block device
210 ;
211 ; AX = Start LBA
212 ; BX = Number of Blocks to Read
213 ; ES:DI = Buffer to store sectors read from disk
214 ; ****************************************************************************
215
216 ; cx = Blocks
217 ; bx = NumberOfBlocks
218 ; si = StartLBA
219
220 ReadBlocks:
221 pusha
222 add eax,dword ptr [bp+LBAOffsetForBootSector] ; Add LBAOffsetForBootSector to Start LBA
223 add eax,dword ptr [bp+HiddenSectors] ; Add HiddenSectors to Start LBA
224 mov esi,eax ; esi = Start LBA
225 mov cx,bx ; cx = Number of blocks to read
226 ReadCylinderLoop:
227 mov bp,07bfch ; bp = 0x7bfc
228 mov eax,esi ; eax = Start LBA
229 xor edx,edx ; edx = 0
230 movzx ebx,word ptr [bp] ; bx = MaxSector
231 div ebx ; ax = StartLBA / MaxSector
232 inc dx ; dx = (StartLBA % MaxSector) + 1
233
234 mov bx,word ptr [bp] ; bx = MaxSector
235 sub bx,dx ; bx = MaxSector - Sector
236 inc bx ; bx = MaxSector - Sector + 1
237 cmp cx,bx ; Compare (Blocks) to (MaxSector - Sector + 1)
238 jg LimitTransfer
239 mov bx,cx ; bx = Blocks
240 LimitTransfer:
241 push ax ; save ax
242 mov ax,es ; ax = es
243 shr ax,(BLOCK_SHIFT-4) ; ax = Number of blocks into mem system
244 and ax,07fh ; ax = Number of blocks into current seg
245 add ax,bx ; ax = End Block number of transfer
246 cmp ax,080h ; See if it crosses a 64K boundry
247 jle NotCrossing64KBoundry ; Branch if not crossing 64K boundry
248 sub ax,080h ; ax = Number of blocks past 64K boundry
249 sub bx,ax ; Decrease transfer size by block overage
250 NotCrossing64KBoundry:
251 pop ax ; restore ax
252
253 push cx
254 mov cl,dl ; cl = (StartLBA % MaxSector) + 1 = Sector
255 xor dx,dx ; dx = 0
256 div word ptr [bp+2] ; ax = ax / (MaxHead + 1) = Cylinder
257 ; dx = ax % (MaxHead + 1) = Head
258
259 push bx ; Save number of blocks to transfer
260 mov dh,dl ; dh = Head
261 mov bp,07c00h ; bp = 0x7c00
262 mov dl,byte ptr [bp+PhysicalDrive] ; dl = Drive Number
263 mov ch,al ; ch = Cylinder
264 mov al,bl ; al = Blocks
265 mov ah,2 ; ah = Function 2
266 mov bx,di ; es:bx = Buffer address
267 int 013h
268 jc DiskError
269 pop bx
270 pop cx
271 movzx ebx,bx
272 add esi,ebx ; StartLBA = StartLBA + NumberOfBlocks
273 sub cx,bx ; Blocks = Blocks - NumberOfBlocks
274 mov ax,es
275 shl bx,(BLOCK_SHIFT-4)
276 add ax,bx
277 mov es,ax ; es:di = es:di + NumberOfBlocks*BLOCK_SIZE
278 cmp cx,0
279 jne ReadCylinderLoop
280 popa
281 ret
282
283 DiskError:
284 push cs
285 pop ds
286 lea si, [ErrorString]
287 mov cx, 7
288 jmp PrintStringAndHalt
289
290 PrintStringAndHalt:
291 mov ax,0b800h
292 mov es,ax
293 mov di,160
294 rep movsw
295 Halt:
296 jmp Halt
297
298 ErrorString:
299 db 'S', 0ch, 'E', 0ch, 'r', 0ch, 'r', 0ch, 'o', 0ch, 'r', 0ch, '!', 0ch
300
301 org 01fah
302 LBAOffsetForBootSector:
303 dd 0h
304
305 org 01feh
306 dw 0aa55h
307
308 ;******************************************************************************
309 ;******************************************************************************
310 ;******************************************************************************
311
312 DELAY_PORT equ 0edh ; Port to use for 1uS delay
313 KBD_CONTROL_PORT equ 060h ; 8042 control port
314 KBD_STATUS_PORT equ 064h ; 8042 status port
315 WRITE_DATA_PORT_CMD equ 0d1h ; 8042 command to write the data port
316 ENABLE_A20_CMD equ 0dfh ; 8042 command to enable A20
317
318 org 200h
319 jmp start
320 Em64String:
321 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
322
323 start:
324 mov ax,cs
325 mov ds,ax
326 mov es,ax
327 mov ss,ax
328 mov sp,MyStack
329
330 ; mov ax,0b800h
331 ; mov es,ax
332 ; mov byte ptr es:[160],'a'
333 ; mov ax,cs
334 ; mov es,ax
335
336 mov ebx,0
337 lea edi,MemoryMap
338 MemMapLoop:
339 mov eax,0e820h
340 mov ecx,20
341 mov edx,'SMAP'
342 int 15h
343 jc MemMapDone
344 add edi,20
345 cmp ebx,0
346 je MemMapDone
347 jmp MemMapLoop
348 MemMapDone:
349 lea eax,MemoryMap
350 sub edi,eax ; Get the address of the memory map
351 mov dword ptr [MemoryMapSize],edi ; Save the size of the memory map
352
353 xor ebx,ebx
354 mov bx,cs ; BX=segment
355 shl ebx,4 ; BX="linear" address of segment base
356 lea eax,[GDT_BASE + ebx] ; EAX=PHYSICAL address of gdt
357 mov dword ptr [gdtr + 2],eax ; Put address of gdt into the gdtr
358 lea eax,[IDT_BASE + ebx] ; EAX=PHYSICAL address of idt
359 mov dword ptr [idtr + 2],eax ; Put address of idt into the idtr
360 lea edx,[MemoryMapSize + ebx] ; Physical base address of the memory map
361
362 add ebx,01000h ; Source of EFI32
363 mov dword ptr [JUMP+2],ebx
364 add ebx,01000h
365 mov esi,ebx ; Source of EFILDR32
366
367 ; mov ax,0b800h
368 ; mov es,ax
369 ; mov byte ptr es:[162],'b'
370 ; mov ax,cs
371 ; mov es,ax
372
373 ;
374 ; Enable A20 Gate
375 ;
376
377 mov ax,2401h ; Enable A20 Gate
378 int 15h
379 jnc A20GateEnabled ; Jump if it suceeded
380
381 ;
382 ; If INT 15 Function 2401 is not supported, then attempt to Enable A20 manually.
383 ;
384
385 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
386 jnz Timeout8042 ; Jump if the 8042 timed out
387 out DELAY_PORT,ax ; Delay 1 uS
388 mov al,WRITE_DATA_PORT_CMD ; 8042 cmd to write output port
389 out KBD_STATUS_PORT,al ; Send command to the 8042
390 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
391 jnz Timeout8042 ; Jump if the 8042 timed out
392 mov al,ENABLE_A20_CMD ; gate address bit 20 on
393 out KBD_CONTROL_PORT,al ; Send command to thre 8042
394 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
395 mov cx,25 ; Delay 25 uS for the command to complete on the 8042
396 Delay25uS:
397 out DELAY_PORT,ax ; Delay 1 uS
398 loop Delay25uS
399 Timeout8042:
400
401
402 A20GateEnabled:
403
404 ;
405 ; DISABLE INTERRUPTS - Entering Protected Mode
406 ;
407
408 cli
409
410 ; mov ax,0b800h
411 ; mov es,ax
412 ; mov byte ptr es:[164],'c'
413 ; mov ax,cs
414 ; mov es,ax
415
416 db 66h
417 lgdt fword ptr [gdtr]
418 db 66h
419 lidt fword ptr [idtr]
420
421 mov eax,cr0
422 or al,1
423 mov cr0,eax
424
425 mov eax,0008h ; Flat data descriptor
426 mov ebp,000400000h ; Destination of EFILDR32
427 mov ebx,000070000h ; Length of copy
428
429 JUMP:
430 ; jmp far 0010:00020000
431 db 066h
432 db 0eah
433 dd 000020000h
434 dw 00010h
435
436 Empty8042InputBuffer:
437 mov cx,0
438 Empty8042Loop:
439 out DELAY_PORT,ax ; Delay 1us
440 in al,KBD_STATUS_PORT ; Read the 8042 Status Port
441 and al,02h ; Check the Input Buffer Full Flag
442 loopnz Empty8042Loop ; Loop until the input buffer is empty or a timout of 65536 uS
443 ret
444
445 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
446 ; data
447 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
448
449 align 02h
450
451 gdtr dw GDT_END - GDT_BASE - 1 ; GDT limit
452 dd 0 ; (GDT base gets set above)
453 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
454 ; global descriptor table (GDT)
455 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
456
457 align 02h
458
459 public GDT_BASE
460 GDT_BASE:
461 ; null descriptor
462 NULL_SEL equ $-GDT_BASE
463 dw 0 ; limit 15:0
464 dw 0 ; base 15:0
465 db 0 ; base 23:16
466 db 0 ; type
467 db 0 ; limit 19:16, flags
468 db 0 ; base 31:24
469
470 ; linear data segment descriptor
471 LINEAR_SEL equ $-GDT_BASE
472 dw 0FFFFh ; limit 0xFFFFF
473 dw 0 ; base 0
474 db 0
475 db 092h ; present, ring 0, data, expand-up, writable
476 db 0CFh ; page-granular, 32-bit
477 db 0
478
479 ; linear code segment descriptor
480 LINEAR_CODE_SEL equ $-GDT_BASE
481 dw 0FFFFh ; limit 0xFFFFF
482 dw 0 ; base 0
483 db 0
484 db 09Ah ; present, ring 0, data, expand-up, writable
485 db 0CFh ; page-granular, 32-bit
486 db 0
487
488 ; system data segment descriptor
489 SYS_DATA_SEL equ $-GDT_BASE
490 dw 0FFFFh ; limit 0xFFFFF
491 dw 0 ; base 0
492 db 0
493 db 092h ; present, ring 0, data, expand-up, writable
494 db 0CFh ; page-granular, 32-bit
495 db 0
496
497 ; system code segment descriptor
498 SYS_CODE_SEL equ $-GDT_BASE
499 dw 0FFFFh ; limit 0xFFFFF
500 dw 0 ; base 0
501 db 0
502 db 09Ah ; present, ring 0, data, expand-up, writable
503 db 0CFh ; page-granular, 32-bit
504 db 0
505
506 ; spare segment descriptor
507 SPARE3_SEL equ $-GDT_BASE
508 dw 0 ; limit 0xFFFFF
509 dw 0 ; base 0
510 db 0
511 db 0 ; present, ring 0, data, expand-up, writable
512 db 0 ; page-granular, 32-bit
513 db 0
514
515 ; spare segment descriptor
516 SPARE4_SEL equ $-GDT_BASE
517 dw 0 ; limit 0xFFFFF
518 dw 0 ; base 0
519 db 0
520 db 0 ; present, ring 0, data, expand-up, writable
521 db 0 ; page-granular, 32-bit
522 db 0
523
524 ; spare segment descriptor
525 SPARE5_SEL equ $-GDT_BASE
526 dw 0 ; limit 0xFFFFF
527 dw 0 ; base 0
528 db 0
529 db 0 ; present, ring 0, data, expand-up, writable
530 db 0 ; page-granular, 32-bit
531 db 0
532
533 GDT_END:
534
535 align 02h
536
537
538
539 idtr dw IDT_END - IDT_BASE - 1 ; IDT limit
540 dd 0 ; (IDT base gets set above)
541 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
542 ; interrupt descriptor table (IDT)
543 ;
544 ; Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ
545 ; mappings. This implementation only uses the system timer and all other
546 ; IRQs will remain masked. The descriptors for vectors 33+ are provided
547 ; for convenience.
548 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
549
550 ;idt_tag db "IDT",0
551 align 02h
552
553 public IDT_BASE
554 IDT_BASE:
555 ; divide by zero (INT 0)
556 DIV_ZERO_SEL equ $-IDT_BASE
557 dw 0 ; offset 15:0
558 dw SYS_CODE_SEL ; selector 15:0
559 db 0 ; 0 for interrupt gate
560 db 0eh OR 80h ; type = 386 interrupt gate, present
561 dw 0 ; offset 31:16
562
563 ; debug exception (INT 1)
564 DEBUG_EXCEPT_SEL equ $-IDT_BASE
565 dw 0 ; offset 15:0
566 dw SYS_CODE_SEL ; selector 15:0
567 db 0 ; 0 for interrupt gate
568 db 0eh OR 80h ; type = 386 interrupt gate, present
569 dw 0 ; offset 31:16
570
571 ; NMI (INT 2)
572 NMI_SEL equ $-IDT_BASE
573 dw 0 ; offset 15:0
574 dw SYS_CODE_SEL ; selector 15:0
575 db 0 ; 0 for interrupt gate
576 db 0eh OR 80h ; type = 386 interrupt gate, present
577 dw 0 ; offset 31:16
578
579 ; soft breakpoint (INT 3)
580 BREAKPOINT_SEL equ $-IDT_BASE
581 dw 0 ; offset 15:0
582 dw SYS_CODE_SEL ; selector 15:0
583 db 0 ; 0 for interrupt gate
584 db 0eh OR 80h ; type = 386 interrupt gate, present
585 dw 0 ; offset 31:16
586
587 ; overflow (INT 4)
588 OVERFLOW_SEL equ $-IDT_BASE
589 dw 0 ; offset 15:0
590 dw SYS_CODE_SEL ; selector 15:0
591 db 0 ; 0 for interrupt gate
592 db 0eh OR 80h ; type = 386 interrupt gate, present
593 dw 0 ; offset 31:16
594
595 ; bounds check (INT 5)
596 BOUNDS_CHECK_SEL equ $-IDT_BASE
597 dw 0 ; offset 15:0
598 dw SYS_CODE_SEL ; selector 15:0
599 db 0 ; 0 for interrupt gate
600 db 0eh OR 80h ; type = 386 interrupt gate, present
601 dw 0 ; offset 31:16
602
603 ; invalid opcode (INT 6)
604 INVALID_OPCODE_SEL equ $-IDT_BASE
605 dw 0 ; offset 15:0
606 dw SYS_CODE_SEL ; selector 15:0
607 db 0 ; 0 for interrupt gate
608 db 0eh OR 80h ; type = 386 interrupt gate, present
609 dw 0 ; offset 31:16
610
611 ; device not available (INT 7)
612 DEV_NOT_AVAIL_SEL equ $-IDT_BASE
613 dw 0 ; offset 15:0
614 dw SYS_CODE_SEL ; selector 15:0
615 db 0 ; 0 for interrupt gate
616 db 0eh OR 80h ; type = 386 interrupt gate, present
617 dw 0 ; offset 31:16
618
619 ; double fault (INT 8)
620 DOUBLE_FAULT_SEL equ $-IDT_BASE
621 dw 0 ; offset 15:0
622 dw SYS_CODE_SEL ; selector 15:0
623 db 0 ; 0 for interrupt gate
624 db 0eh OR 80h ; type = 386 interrupt gate, present
625 dw 0 ; offset 31:16
626
627 ; Coprocessor segment overrun - reserved (INT 9)
628 RSVD_INTR_SEL1 equ $-IDT_BASE
629 dw 0 ; offset 15:0
630 dw SYS_CODE_SEL ; selector 15:0
631 db 0 ; 0 for interrupt gate
632 db 0eh OR 80h ; type = 386 interrupt gate, present
633 dw 0 ; offset 31:16
634
635 ; invalid TSS (INT 0ah)
636 INVALID_TSS_SEL equ $-IDT_BASE
637 dw 0 ; offset 15:0
638 dw SYS_CODE_SEL ; selector 15:0
639 db 0 ; 0 for interrupt gate
640 db 0eh OR 80h ; type = 386 interrupt gate, present
641 dw 0 ; offset 31:16
642
643 ; segment not present (INT 0bh)
644 SEG_NOT_PRESENT_SEL equ $-IDT_BASE
645 dw 0 ; offset 15:0
646 dw SYS_CODE_SEL ; selector 15:0
647 db 0 ; 0 for interrupt gate
648 db 0eh OR 80h ; type = 386 interrupt gate, present
649 dw 0 ; offset 31:16
650
651 ; stack fault (INT 0ch)
652 STACK_FAULT_SEL equ $-IDT_BASE
653 dw 0 ; offset 15:0
654 dw SYS_CODE_SEL ; selector 15:0
655 db 0 ; 0 for interrupt gate
656 db 0eh OR 80h ; type = 386 interrupt gate, present
657 dw 0 ; offset 31:16
658
659 ; general protection (INT 0dh)
660 GP_FAULT_SEL equ $-IDT_BASE
661 dw 0 ; offset 15:0
662 dw SYS_CODE_SEL ; selector 15:0
663 db 0 ; 0 for interrupt gate
664 db 0eh OR 80h ; type = 386 interrupt gate, present
665 dw 0 ; offset 31:16
666
667 ; page fault (INT 0eh)
668 PAGE_FAULT_SEL equ $-IDT_BASE
669 dw 0 ; offset 15:0
670 dw SYS_CODE_SEL ; selector 15:0
671 db 0 ; 0 for interrupt gate
672 db 0eh OR 80h ; type = 386 interrupt gate, present
673 dw 0 ; offset 31:16
674
675 ; Intel reserved - do not use (INT 0fh)
676 RSVD_INTR_SEL2 equ $-IDT_BASE
677 dw 0 ; offset 15:0
678 dw SYS_CODE_SEL ; selector 15:0
679 db 0 ; 0 for interrupt gate
680 db 0eh OR 80h ; type = 386 interrupt gate, present
681 dw 0 ; offset 31:16
682
683 ; floating point error (INT 10h)
684 FLT_POINT_ERR_SEL equ $-IDT_BASE
685 dw 0 ; offset 15:0
686 dw SYS_CODE_SEL ; selector 15:0
687 db 0 ; 0 for interrupt gate
688 db 0eh OR 80h ; type = 386 interrupt gate, present
689 dw 0 ; offset 31:16
690
691 ; alignment check (INT 11h)
692 ALIGNMENT_CHECK_SEL equ $-IDT_BASE
693 dw 0 ; offset 15:0
694 dw SYS_CODE_SEL ; selector 15:0
695 db 0 ; 0 for interrupt gate
696 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
697 dw 0 ; offset 31:16
698
699 ; machine check (INT 12h)
700 MACHINE_CHECK_SEL equ $-IDT_BASE
701 dw 0 ; offset 15:0
702 dw SYS_CODE_SEL ; selector 15:0
703 db 0 ; 0 for interrupt gate
704 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
705 dw 0 ; offset 31:16
706
707 ; SIMD floating-point exception (INT 13h)
708 SIMD_EXCEPTION_SEL equ $-IDT_BASE
709 dw 0 ; offset 15:0
710 dw SYS_CODE_SEL ; selector 15:0
711 db 0 ; 0 for interrupt gate
712 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
713 dw 0 ; offset 31:16
714
715 ; 85 unspecified descriptors, First 12 of them are reserved, the rest are avail
716 db (85 * 8) dup(0)
717
718 ; IRQ 0 (System timer) - (INT 68h)
719 IRQ0_SEL equ $-IDT_BASE
720 dw 0 ; offset 15:0
721 dw SYS_CODE_SEL ; selector 15:0
722 db 0 ; 0 for interrupt gate
723 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
724 dw 0 ; offset 31:16
725
726 ; IRQ 1 (8042 Keyboard controller) - (INT 69h)
727 IRQ1_SEL equ $-IDT_BASE
728 dw 0 ; offset 15:0
729 dw SYS_CODE_SEL ; selector 15:0
730 db 0 ; 0 for interrupt gate
731 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
732 dw 0 ; offset 31:16
733
734 ; Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah)
735 IRQ2_SEL equ $-IDT_BASE
736 dw 0 ; offset 15:0
737 dw SYS_CODE_SEL ; selector 15:0
738 db 0 ; 0 for interrupt gate
739 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
740 dw 0 ; offset 31:16
741
742 ; IRQ 3 (COM 2) - (INT 6bh)
743 IRQ3_SEL equ $-IDT_BASE
744 dw 0 ; offset 15:0
745 dw SYS_CODE_SEL ; selector 15:0
746 db 0 ; 0 for interrupt gate
747 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
748 dw 0 ; offset 31:16
749
750 ; IRQ 4 (COM 1) - (INT 6ch)
751 IRQ4_SEL equ $-IDT_BASE
752 dw 0 ; offset 15:0
753 dw SYS_CODE_SEL ; selector 15:0
754 db 0 ; 0 for interrupt gate
755 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
756 dw 0 ; offset 31:16
757
758 ; IRQ 5 (LPT 2) - (INT 6dh)
759 IRQ5_SEL equ $-IDT_BASE
760 dw 0 ; offset 15:0
761 dw SYS_CODE_SEL ; selector 15:0
762 db 0 ; 0 for interrupt gate
763 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
764 dw 0 ; offset 31:16
765
766 ; IRQ 6 (Floppy controller) - (INT 6eh)
767 IRQ6_SEL equ $-IDT_BASE
768 dw 0 ; offset 15:0
769 dw SYS_CODE_SEL ; selector 15:0
770 db 0 ; 0 for interrupt gate
771 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
772 dw 0 ; offset 31:16
773
774 ; IRQ 7 (LPT 1) - (INT 6fh)
775 IRQ7_SEL equ $-IDT_BASE
776 dw 0 ; offset 15:0
777 dw SYS_CODE_SEL ; selector 15:0
778 db 0 ; 0 for interrupt gate
779 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
780 dw 0 ; offset 31:16
781
782 ; IRQ 8 (RTC Alarm) - (INT 70h)
783 IRQ8_SEL equ $-IDT_BASE
784 dw 0 ; offset 15:0
785 dw SYS_CODE_SEL ; selector 15:0
786 db 0 ; 0 for interrupt gate
787 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
788 dw 0 ; offset 31:16
789
790 ; IRQ 9 - (INT 71h)
791 IRQ9_SEL equ $-IDT_BASE
792 dw 0 ; offset 15:0
793 dw SYS_CODE_SEL ; selector 15:0
794 db 0 ; 0 for interrupt gate
795 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
796 dw 0 ; offset 31:16
797
798 ; IRQ 10 - (INT 72h)
799 IRQ10_SEL equ $-IDT_BASE
800 dw 0 ; offset 15:0
801 dw SYS_CODE_SEL ; selector 15:0
802 db 0 ; 0 for interrupt gate
803 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
804 dw 0 ; offset 31:16
805
806 ; IRQ 11 - (INT 73h)
807 IRQ11_SEL equ $-IDT_BASE
808 dw 0 ; offset 15:0
809 dw SYS_CODE_SEL ; selector 15:0
810 db 0 ; 0 for interrupt gate
811 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
812 dw 0 ; offset 31:16
813
814 ; IRQ 12 (PS/2 mouse) - (INT 74h)
815 IRQ12_SEL equ $-IDT_BASE
816 dw 0 ; offset 15:0
817 dw SYS_CODE_SEL ; selector 15:0
818 db 0 ; 0 for interrupt gate
819 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
820 dw 0 ; offset 31:16
821
822 ; IRQ 13 (Floating point error) - (INT 75h)
823 IRQ13_SEL equ $-IDT_BASE
824 dw 0 ; offset 15:0
825 dw SYS_CODE_SEL ; selector 15:0
826 db 0 ; 0 for interrupt gate
827 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
828 dw 0 ; offset 31:16
829
830 ; IRQ 14 (Secondary IDE) - (INT 76h)
831 IRQ14_SEL equ $-IDT_BASE
832 dw 0 ; offset 15:0
833 dw SYS_CODE_SEL ; selector 15:0
834 db 0 ; 0 for interrupt gate
835 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
836 dw 0 ; offset 31:16
837
838 ; IRQ 15 (Primary IDE) - (INT 77h)
839 IRQ15_SEL equ $-IDT_BASE
840 dw 0 ; offset 15:0
841 dw SYS_CODE_SEL ; selector 15:0
842 db 0 ; 0 for interrupt gate
843 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
844 dw 0 ; offset 31:16
845
846 IDT_END:
847
848 align 02h
849
850 MemoryMapSize dd 0
851 MemoryMap dd 0,0,0,0,0,0,0,0
852 dd 0,0,0,0,0,0,0,0
853 dd 0,0,0,0,0,0,0,0
854 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
882 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
883 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
884
885 org 0fe0h
886 MyStack:
887 ; below is the pieces of the IVT that is used to redirect INT 68h - 6fh
888 ; back to INT 08h - 0fh when in real mode... It is 'org'ed to a
889 ; known low address (20f00) so it can be set up by PlMapIrqToVect in
890 ; 8259.c
891
892 int 8
893 iret
894
895 int 9
896 iret
897
898 int 10
899 iret
900
901 int 11
902 iret
903
904 int 12
905 iret
906
907 int 13
908 iret
909
910 int 14
911 iret
912
913 int 15
914 iret
915
916
917 org 0ffeh
918 BlockSignature:
919 dw 0aa55h
920
921 end