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1#------------------------------------------------------------------------------\r
2#*\r
3#* Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>\r
4#* This program and the accompanying materials \r
5#* are licensed and made available under the terms and conditions of the BSD License \r
6#* which accompanies this distribution. The full text of the license may be found at \r
7#* http://opensource.org/licenses/bsd-license.php \r
8#* \r
9#* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r
10#* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r
11#* \r
12#* st16_64.asm\r
13#* \r
14#* Abstract:\r
15#*\r
16#------------------------------------------------------------------------------\r
17\r
18\r
19 .stack: \r
20 .486p: \r
21 .code16\r
22\r
23.equ FAT_DIRECTORY_ENTRY_SIZE, 0x020\r
24.equ FAT_DIRECTORY_ENTRY_SHIFT, 5\r
25.equ BLOCK_SIZE, 0x0200\r
26.equ BLOCK_MASK, 0x01ff\r
27.equ BLOCK_SHIFT, 9\r
28\r
29 .org 0x0\r
30\r
31.global _start\r
32_start:\r
33\r
34Ia32Jump: \r
35 jmp BootSectorEntryPoint # JMP inst - 3 bytes\r
36 nop\r
37\r
38OemId: .ascii "INTEL " # OemId - 8 bytes\r
39\r
40SectorSize: .word 0 # Sector Size - 16 bits\r
41SectorsPerCluster: .byte 0 # Sector Per Cluster - 8 bits\r
42ReservedSectors: .word 0 # Reserved Sectors - 16 bits\r
43NoFats: .byte 0 # Number of FATs - 8 bits\r
44RootEntries: .word 0 # Root Entries - 16 bits\r
45Sectors: .word 0 # Number of Sectors - 16 bits\r
46Media: .byte 0 # Media - 8 bits - ignored\r
47SectorsPerFat: .word 0 # Sectors Per FAT - 16 bits\r
48SectorsPerTrack: .word 0 # Sectors Per Track - 16 bits - ignored\r
49Heads: .word 0 # Heads - 16 bits - ignored\r
50HiddenSectors: .long 0 # Hidden Sectors - 32 bits - ignored\r
51LargeSectors: .long 0 # Large Sectors - 32 bits \r
52PhysicalDrive: .byte 0 # PhysicalDriveNumber - 8 bits - ignored\r
53CurrentHead: .byte 0 # Current Head - 8 bits\r
54Signature: .byte 0 # Signature - 8 bits - ignored\r
55VolId: .ascii " " # Volume Serial Number- 4 bytes\r
56FatLabel: .ascii " " # Label - 11 bytes\r
57SystemId: .ascii "FAT16 " # SystemId - 8 bytes\r
58\r
59BootSectorEntryPoint: \r
60 # ASSUME ds:@code\r
61 # ASSUME ss:@code\r
62 # ds = 1000, es = 2000 + x (size of first cluster >> 4)\r
63 # cx = Start Cluster of EfiLdr\r
64 # dx = Start Cluster of Efivar.bin\r
65\r
66# Re use the BPB data stored in Boot Sector\r
67 movw $0x7c00,%bp\r
68\r
69 pushw %cx\r
70# Read Efivar.bin\r
71# 1000:dx = DirectoryEntry of Efivar.bin -> BS.com has filled already\r
72 movw $0x1900,%ax\r
73 movw %ax,%es\r
74 testw %dx,%dx\r
75 jnz CheckVarStoreSize\r
76\r
77 movb $1,%al\r
78NoVarStore: \r
79 pushw %es\r
80# Set the 5th byte start @ 0:19000 to non-zero indicating we should init var store header in DxeIpl\r
81 movb %al, %es:(4)\r
82 jmp SaveVolumeId\r
83\r
84CheckVarStoreSize: \r
85 movw %dx,%di\r
86 cmpl $0x4000, %ds:2(%di)\r
87 movb $2,%al\r
88 jne NoVarStore\r
89\r
90LoadVarStore: \r
91 movb $0,%al\r
92 movb %al, %es:(4)\r
93 movw (%di), %cx\r
94# ES:DI = 1500:0\r
95 xorw %di,%di\r
96 pushw %es\r
97 movw $0x1500,%ax\r
98 movw %ax,%es\r
99 call ReadFile\r
100SaveVolumeId: \r
101 popw %es\r
102 movw VolId(%bp), %ax\r
103 movw %ax, %es:(0) # Save Volume Id to 0:19000. we will find the correct volume according to this VolumeId\r
104 movw VolId+2(%bp), %ax\r
105 movw %ax, %es:(2)\r
106\r
107# Read Efildr\r
108 popw %cx\r
109# cx = Start Cluster of Efildr -> BS.com has filled already\r
110# ES:DI = 2000:0, first cluster will be read again\r
111 xorw %di,%di # di = 0\r
112 movw $0x2000,%ax\r
113 movw %ax,%es\r
114 call ReadFile\r
115 movw %cs,%ax\r
116 movw %ax, %cs:JumpSegment\r
117\r
118CheckEm64T: \r
119 movl $0x80000001,%eax\r
120# cpuid\r
121 .word 0xA20F\r
122 btl $29,%edx\r
123 jc CheckEm64TPass\r
124 pushw %cs\r
125 popw %ds\r
126 leaw Em64String,%si\r
127 movw $18,%cx\r
128 jmp PrintStringAndHalt\r
129CheckEm64TPass: \r
130JumpFarInstruction: \r
131 .byte 0xea\r
132JumpOffset: \r
133 .word 0x200\r
134JumpSegment: \r
135 .word 0x2000\r
136\r
137\r
138\r
139# ****************************************************************************\r
140# ReadFile\r
141#\r
142# Arguments:\r
143# CX = Start Cluster of File\r
144# ES:DI = Buffer to store file content read from disk\r
145#\r
146# Return:\r
147# (ES << 4 + DI) = end of file content Buffer\r
148#\r
149# ****************************************************************************\r
150ReadFile: \r
151# si = NumberOfClusters\r
152# cx = ClusterNumber\r
153# dx = CachedFatSectorNumber\r
154# ds:0000 = CacheFatSectorBuffer\r
155# es:di = Buffer to load file\r
156# bx = NextClusterNumber\r
157 pusha\r
158 movw $1,%si # NumberOfClusters = 1\r
159 pushw %cx # Push Start Cluster onto stack\r
160 movw $0xfff,%dx # CachedFatSectorNumber = 0xfff\r
161FatChainLoop: \r
162 movw %cx,%ax # ax = ClusterNumber \r
163 andw $0xfff8,%ax # ax = ax & 0xfff8\r
164 cmpw $0xfff8,%ax # See if this is the last cluster\r
165 je FoundLastCluster # Jump if last cluster found\r
166 movw %cx,%ax # ax = ClusterNumber\r
167 shlw %ax # FatOffset = ClusterNumber * 2\r
168 pushw %si # Save si\r
169 movw %ax,%si # si = FatOffset\r
170 shrw $BLOCK_SHIFT, %ax # ax = FatOffset >> BLOCK_SHIFT\r
171 addw ReservedSectors(%bp), %ax # ax = FatSectorNumber = ReservedSectors + (FatOffset >> BLOCK_OFFSET)\r
172 andw $BLOCK_MASK, %si # si = FatOffset & BLOCK_MASK\r
173 cmpw %dx,%ax # Compare FatSectorNumber to CachedFatSectorNumber\r
174 je SkipFatRead\r
175 movw $2,%bx\r
176 pushw %es\r
177 pushw %ds\r
178 popw %es\r
179 call ReadBlocks # Read 2 blocks starting at AX storing at ES:DI\r
180 popw %es\r
181 movw %ax,%dx # CachedFatSectorNumber = FatSectorNumber\r
182SkipFatRead: \r
183 movw (%si), %bx # bx = NextClusterNumber\r
184 movw %cx,%ax # ax = ClusterNumber\r
185 popw %si # Restore si\r
186 decw %bx # bx = NextClusterNumber - 1\r
187 cmpw %cx,%bx # See if (NextClusterNumber-1)==ClusterNumber\r
188 jne ReadClusters\r
189 incw %bx # bx = NextClusterNumber\r
190 incw %si # NumberOfClusters++\r
191 movw %bx,%cx # ClusterNumber = NextClusterNumber\r
192 jmp FatChainLoop\r
193ReadClusters: \r
194 incw %bx\r
195 popw %ax # ax = StartCluster\r
196 pushw %bx # StartCluster = NextClusterNumber\r
197 movw %bx,%cx # ClusterNumber = NextClusterNumber\r
198 subw $2,%ax # ax = StartCluster - 2\r
199 xorb %bh,%bh\r
200 movb SectorsPerCluster(%bp), %bl # bx = SectorsPerCluster\r
201 mulw %bx # ax = (StartCluster - 2) * SectorsPerCluster\r
202 addw (%bp), %ax # ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster\r
203 pushw %ax # save start sector\r
204 movw %si,%ax # ax = NumberOfClusters\r
205 mulw %bx # ax = NumberOfClusters * SectorsPerCluster\r
206 movw %ax,%bx # bx = Number of Sectors\r
207 popw %ax # ax = Start Sector\r
208 call ReadBlocks\r
209 movw $1,%si # NumberOfClusters = 1\r
210 jmp FatChainLoop\r
211FoundLastCluster: \r
212 popw %cx\r
213 popa\r
214 ret\r
215\r
216\r
217# ****************************************************************************\r
218# ReadBlocks - Reads a set of blocks from a block device\r
219#\r
220# AX = Start LBA\r
221# BX = Number of Blocks to Read\r
222# ES:DI = Buffer to store sectors read from disk\r
223# ****************************************************************************\r
224\r
225# cx = Blocks\r
226# bx = NumberOfBlocks\r
227# si = StartLBA\r
228\r
229ReadBlocks: \r
230 pusha\r
231 addl LBAOffsetForBootSector(%bp), %eax # Add LBAOffsetForBootSector to Start LBA\r
232 addl HiddenSectors(%bp), %eax # Add HiddenSectors to Start LBA\r
233 movl %eax,%esi # esi = Start LBA\r
234 movw %bx,%cx # cx = Number of blocks to read\r
235ReadCylinderLoop: \r
236 movw $0x7bfc,%bp # bp = 0x7bfc\r
237 movl %esi,%eax # eax = Start LBA\r
238 xorl %edx,%edx # edx = 0\r
239 movzwl (%bp), %ebx # bx = MaxSector\r
240 divl %ebx # ax = StartLBA / MaxSector\r
241 incw %dx # dx = (StartLBA % MaxSector) + 1\r
242\r
243 movw (%bp), %bx # bx = MaxSector\r
244 subw %dx,%bx # bx = MaxSector - Sector\r
245 incw %bx # bx = MaxSector - Sector + 1\r
246 cmpw %bx,%cx # Compare (Blocks) to (MaxSector - Sector + 1)\r
247 jg LimitTransfer\r
248 movw %cx,%bx # bx = Blocks\r
249LimitTransfer: \r
250 pushw %ax # save ax\r
251 movw %es,%ax # ax = es\r
252 shrw $(BLOCK_SHIFT-4), %ax # ax = Number of blocks into mem system\r
253 andw $0x7f,%ax # ax = Number of blocks into current seg\r
254 addw %bx,%ax # ax = End Block number of transfer\r
255 cmpw $0x80,%ax # See if it crosses a 64K boundry\r
256 jle NotCrossing64KBoundry # Branch if not crossing 64K boundry\r
257 subw $0x80,%ax # ax = Number of blocks past 64K boundry\r
258 subw %ax,%bx # Decrease transfer size by block overage\r
259NotCrossing64KBoundry: \r
260 popw %ax # restore ax\r
261\r
262 pushw %cx\r
263 movb %dl,%cl # cl = (StartLBA % MaxSector) + 1 = Sector\r
264 xorw %dx,%dx # dx = 0\r
265 divw 2(%bp) # ax = ax / (MaxHead + 1) = Cylinder \r
266 # dx = ax % (MaxHead + 1) = Head\r
267\r
268 pushw %bx # Save number of blocks to transfer\r
269 movb %dl,%dh # dh = Head\r
270 movw $0x7c00,%bp # bp = 0x7c00\r
271 movb PhysicalDrive(%bp), %dl # dl = Drive Number\r
272 movb %al,%ch # ch = Cylinder\r
273 movb %bl,%al # al = Blocks\r
274 movb $2,%ah # ah = Function 2\r
275 movw %di,%bx # es:bx = Buffer address\r
276 int $0x13\r
277 jc DiskError\r
278 popw %bx\r
279 popw %cx\r
280 movzwl %bx,%ebx\r
281 addl %ebx,%esi # StartLBA = StartLBA + NumberOfBlocks\r
282 subw %bx,%cx # Blocks = Blocks - NumberOfBlocks\r
283 movw %es,%ax\r
284 shlw $(BLOCK_SHIFT-4), %bx\r
285 addw %bx,%ax\r
286 movw %ax,%es # es:di = es:di + NumberOfBlocks*BLOCK_SIZE\r
287 cmpw $0,%cx\r
288 jne ReadCylinderLoop\r
289 popa\r
290 ret\r
291\r
292DiskError: \r
293 pushw %cs\r
294 popw %ds\r
295 leaw ErrorString,%si\r
296 movw $7,%cx\r
297 jmp PrintStringAndHalt\r
298\r
299PrintStringAndHalt: \r
300 movw $0xb800,%ax\r
301 movw %ax,%es\r
302 movw $160,%di\r
303 rep\r
304 movsw\r
305Halt: \r
306 jmp Halt\r
307\r
308ErrorString: \r
309 .byte 'S', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, 'o', 0x0c, 'r', 0x0c, '!',0x0c\r
310\r
311 .org 0x01fa\r
312LBAOffsetForBootSector: \r
313 .long 0x0\r
314\r
315 .org 0x01fe\r
316 .word 0xaa55\r
317\r
318#******************************************************************************\r
319#******************************************************************************\r
320#******************************************************************************\r
321\r
322.equ DELAY_PORT, 0x0ed # Port to use for 1uS delay\r
323.equ KBD_CONTROL_PORT, 0x060 # 8042 control port \r
324.equ KBD_STATUS_PORT, 0x064 # 8042 status port \r
325.equ WRITE_DATA_PORT_CMD, 0x0d1 # 8042 command to write the data port\r
326.equ ENABLE_A20_CMD, 0x0df # 8042 command to enable A20\r
327\r
328 .org 0x200\r
329 jmp start\r
330Em64String: \r
331.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\r
332\r
333start: \r
334 movw %cs,%ax\r
335 movw %ax,%ds\r
336 movw %ax,%es\r
337 movw %ax,%ss\r
338 movw $MyStack, %sp\r
339\r
340# mov ax,0b800h\r
341# mov es,ax\r
342# mov byte ptr es:[160],'a'\r
343# mov ax,cs\r
344# mov es,ax\r
345\r
346 movl $0,%ebx\r
347 leal MemoryMap, %edi\r
348MemMapLoop: \r
349 movl $0xe820,%eax\r
350 movl $20,%ecx\r
351 movl $0x534d4150, %edx # SMAP\r
352 int $0x15\r
353 jc MemMapDone\r
354 addl $20,%edi\r
355 cmpl $0,%ebx\r
356 je MemMapDone\r
357 jmp MemMapLoop\r
358MemMapDone: \r
359 leal MemoryMap, %eax\r
360 subl %eax,%edi # Get the address of the memory map\r
361 movl %edi, MemoryMapSize # Save the size of the memory map\r
362\r
363 xorl %ebx,%ebx\r
364 movw %cs,%bx # BX=segment\r
365 shll $4,%ebx # BX="linear" address of segment base\r
366 leal GDT_BASE(%ebx), %eax # EAX=PHYSICAL address of gdt\r
367 movl %eax, (gdtr + 2) # Put address of gdt into the gdtr\r
368 leal IDT_BASE(%ebx), %eax # EAX=PHYSICAL address of idt\r
369 movl %eax, (idtr + 2) # Put address of idt into the idtr\r
370 leal MemoryMapSize(%ebx), %edx # Physical base address of the memory map\r
371\r
372# mov ax,0b800h\r
373# mov es,ax\r
374# mov byte ptr es:[162],'b'\r
375# mov ax,cs\r
376# mov es,ax\r
377\r
378#\r
379# Enable A20 Gate \r
380#\r
381\r
382 movw $0x2401,%ax # Enable A20 Gate\r
383 int $0x15\r
384 jnc A20GateEnabled # Jump if it suceeded\r
385\r
386#\r
387# If INT 15 Function 2401 is not supported, then attempt to Enable A20 manually.\r
388#\r
389\r
390 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller\r
391 jnz Timeout8042 # Jump if the 8042 timed out\r
392 outw %ax, $DELAY_PORT # Delay 1 uS\r
393 movb $WRITE_DATA_PORT_CMD, %al # 8042 cmd to write output port\r
394 outb %al, $KBD_STATUS_PORT # Send command to the 8042\r
395 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller\r
396 jnz Timeout8042 # Jump if the 8042 timed out\r
397 movb $ENABLE_A20_CMD, %al # gate address bit 20 on\r
398 outb %al, $KBD_CONTROL_PORT # Send command to thre 8042\r
399 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller\r
400 movw $25,%cx # Delay 25 uS for the command to complete on the 8042\r
401Delay25uS: \r
402 outw %ax, $DELAY_PORT # Delay 1 uS\r
403 loop Delay25uS\r
404Timeout8042: \r
405\r
406\r
407A20GateEnabled: \r
408\r
409#\r
410# DISABLE INTERRUPTS - Entering Protected Mode\r
411#\r
412\r
413 cli\r
414\r
415# mov ax,0b800h\r
416# mov es,ax\r
417# mov byte ptr es:[164],'c'\r
418# mov ax,cs\r
419# mov es,ax\r
420\r
421 leal OffsetIn32BitProtectedMode, %eax\r
422 addl $0x20000+0x6,%eax\r
423 movl %eax, OffsetIn32BitProtectedMode \r
424\r
425 leal OffsetInLongMode, %eax\r
426 addl $0x20000+0x6,%eax\r
427 movl %eax, OffsetInLongMode \r
428\r
429 #\r
430 # load GDT\r
431 #\r
432 .byte 0x66\r
433 lgdt gdtr\r
434\r
435 #\r
436 # Enable Protect Mode (set CR0.PE=1)\r
437 #\r
438 movl %cr0, %eax # Read CR0.\r
439 orl $0x1,%eax # Set PE=1\r
440 movl %eax, %cr0 # Write CR0.\r
441 .byte 0x66\r
442 .byte 0xea # jmp far 16:32\r
443OffsetIn32BitProtectedMode: \r
444 .long 0x0000000 # offset $+8 (In32BitProtectedMode)\r
445 .word 0x10 # selector (flat CS)\r
446In32BitProtectedMode: \r
447\r
448#\r
449# Entering Long Mode\r
450#\r
451 .byte 0x66\r
452 movw $8,%ax\r
453 movw %ax,%ds\r
454 movw %ax,%es\r
455 movw %ax,%ss\r
456\r
457 #\r
458 # Enable the 64-bit page-translation-table entries by\r
459 # setting CR4.PAE=1 (this is _required_ before activating\r
460 # long mode). Paging is not enabled until after long mode\r
461 # is enabled.\r
462 #\r
463 .byte 0xf\r
464 .byte 0x20\r
465 .byte 0xe0\r
466# mov eax, cr4\r
467 btsl $5,%eax\r
468 .byte 0xf\r
469 .byte 0x22\r
470 .byte 0xe0\r
471# mov cr4, eax\r
472\r
473 #\r
474 # This is the Trapolean Page Tables that are guarenteed\r
475 # under 4GB.\r
476 #\r
477 # Address Map:\r
478 # 10000 ~ 12000 - efildr (loaded)\r
479 # 20000 ~ 21000 - start64.com\r
480 # 21000 ~ 22000 - efi64.com\r
481 # 22000 ~ 90000 - efildr\r
482 # 90000 ~ 96000 - 4G pagetable (will be reload later)\r
483 #\r
484 .byte 0xb8\r
485 .long 0x90000\r
486# mov eax, 90000h\r
487 movl %eax, %cr3\r
488\r
489 #\r
490 # Enable long mode (set EFER.LME=1).\r
491 #\r
492 .byte 0xb9\r
493 .long 0xc0000080\r
494# mov ecx, 0c0000080h ; EFER MSR number.\r
495 .byte 0xf\r
496 .byte 0x32\r
497# rdmsr ; Read EFER.\r
498 .byte 0xf\r
499 .byte 0xba\r
500 .byte 0xe8\r
501 .byte 0x8\r
502# bts eax, 8 ; Set LME=1.\r
503 .byte 0xf\r
504 .byte 0x30\r
505# wrmsr ; Write EFER.\r
506\r
507 #\r
508 # Enable paging to activate long mode (set CR0.PG=1)\r
509 #\r
510 movl %cr0, %eax # Read CR0.\r
511 .byte 0xf\r
512 .byte 0xba\r
513 .byte 0xe8\r
514 .byte 0x1f\r
515# bts eax, 31 ; Set PG=1.\r
516 movl %eax, %cr0 # Write CR0.\r
517 jmp GoToLongMode\r
518GoToLongMode: \r
519\r
520 .byte 0x67\r
521 .byte 0xea # Far Jump $+9:Selector to reload CS\r
522OffsetInLongMode: \r
523 .long 00000000 # $+9 Offset is ensuing instruction boundary\r
524 .word 0x38 # Selector is our code selector, 38h\r
525\r
526InLongMode: \r
527 .byte 0x66\r
528 movw $0x30,%ax\r
529 movw %ax,%ds\r
530\r
531 .byte 0x66\r
532 movw $0x18,%ax\r
533 movw %ax,%es\r
534 movw %ax,%ss\r
535 movw %ax,%ds\r
536\r
537 .byte 0xbd\r
538 .long 0x400000\r
539# mov ebp,000400000h ; Destination of EFILDR32\r
540 .byte 0xbb\r
541 .long 0x70000\r
542# mov ebx,000070000h ; Length of copy\r
543\r
544 #\r
545 # load idt later\r
546 #\r
547 .byte 0x48\r
548 .byte 0x33\r
549 .byte 0xc0\r
550# xor rax, rax\r
551 .byte 0x66\r
552 movw $idtr, %ax\r
553 .byte 0x48\r
554 .byte 0x5\r
555 .long 0x20000\r
556# add rax, 20000h\r
557\r
558 .byte 0xf\r
559 .byte 0x1\r
560 .byte 0x18\r
561# lidt fword ptr [rax]\r
562\r
563 .byte 0x48\r
564 .byte 0xc7\r
565 .byte 0xc0\r
566 .long 0x21000\r
567# mov rax, 21000h\r
568 .byte 0x50\r
569# push rax\r
570\r
571# ret\r
572 .byte 0xc3\r
573\r
574Empty8042InputBuffer: \r
575 movw $0,%cx\r
576Empty8042Loop: \r
577 outw %ax, $DELAY_PORT # Delay 1us\r
578 inb $KBD_STATUS_PORT, %al # Read the 8042 Status Port\r
579 andb $0x2,%al # Check the Input Buffer Full Flag\r
580 loopnz Empty8042Loop # Loop until the input buffer is empty or a timout of 65536 uS\r
581 ret\r
582\r
583##############################################################################\r
584# data\r
585##############################################################################\r
586\r
587 .p2align 1\r
588\r
589 gdtr: .long GDT_END - GDT_BASE - 1 # GDT limit \r
590 .long 0 # (GDT base gets set above)\r
591##############################################################################\r
592# global descriptor table (GDT)\r
593##############################################################################\r
594\r
595 .p2align 1\r
596\r
597GDT_BASE: \r
598# null descriptor\r
599.equ NULL_SEL, .-GDT_BASE # Selector [0x0]\r
600 .word 0 # limit 15:0\r
601 .word 0 # base 15:0\r
602 .byte 0 # base 23:16\r
603 .byte 0 # type\r
604 .byte 0 # limit 19:16, flags\r
605 .byte 0 # base 31:24\r
606\r
607# linear data segment descriptor\r
608.equ LINEAR_SEL, .-GDT_BASE # Selector [0x8]\r
609 .word 0xFFFF # limit 0xFFFFF\r
610 .word 0 # base 0\r
611 .byte 0\r
612 .byte 0x92 # present, ring 0, data, expand-up, writable\r
613 .byte 0xCF # page-granular, 32-bit\r
614 .byte 0\r
615\r
616# linear code segment descriptor\r
617.equ LINEAR_CODE_SEL, .-GDT_BASE # Selector [0x10]\r
618 .word 0xFFFF # limit 0xFFFFF\r
619 .word 0 # base 0\r
620 .byte 0\r
621 .byte 0x9A # present, ring 0, data, expand-up, writable\r
622 .byte 0xCF # page-granular, 32-bit\r
623 .byte 0\r
624\r
625# system data segment descriptor\r
626.equ SYS_DATA_SEL, .-GDT_BASE # Selector [0x18]\r
627 .word 0xFFFF # limit 0xFFFFF\r
628 .word 0 # base 0\r
629 .byte 0\r
630 .byte 0x92 # present, ring 0, data, expand-up, writable\r
631 .byte 0xCF # page-granular, 32-bit\r
632 .byte 0\r
633\r
634# system code segment descriptor\r
635.equ SYS_CODE_SEL, .-GDT_BASE # Selector [0x20]\r
636 .word 0xFFFF # limit 0xFFFFF\r
637 .word 0 # base 0\r
638 .byte 0\r
639 .byte 0x9A # present, ring 0, data, expand-up, writable\r
640 .byte 0xCF # page-granular, 32-bit\r
641 .byte 0\r
642\r
643# spare segment descriptor\r
644.equ SPARE3_SEL, .-GDT_BASE # Selector [0x28]\r
645 .word 0 # limit 0xFFFFF\r
646 .word 0 # base 0\r
647 .byte 0\r
648 .byte 0 # present, ring 0, data, expand-up, writable\r
649 .byte 0 # page-granular, 32-bit\r
650 .byte 0\r
651\r
652#\r
653# system data segment descriptor\r
654#\r
655.equ SYS_DATA64_SEL, .-GDT_BASE # Selector [0x30]\r
656 .word 0xFFFF # limit 0xFFFFF\r
657 .word 0 # base 0\r
658 .byte 0\r
659 .byte 0x92 # P | DPL [1..2] | 1 | 1 | C | R | A\r
660 .byte 0xCF # G | D | L | AVL | Segment [19..16]\r
661 .byte 0\r
662\r
663#\r
664# system code segment descriptor\r
665#\r
666.equ SYS_CODE64_SEL, .-GDT_BASE # Selector [0x38]\r
667 .word 0xFFFF # limit 0xFFFFF\r
668 .word 0 # base 0\r
669 .byte 0\r
670 .byte 0x9A # P | DPL [1..2] | 1 | 1 | C | R | A\r
671 .byte 0xAF # G | D | L | AVL | Segment [19..16]\r
672 .byte 0\r
673\r
674# spare segment descriptor\r
675.equ SPARE4_SEL, .-GDT_BASE # Selector [0x40]\r
676 .word 0 # limit 0xFFFFF\r
677 .word 0 # base 0\r
678 .byte 0\r
679 .byte 0 # present, ring 0, data, expand-up, writable\r
680 .byte 0 # page-granular, 32-bit\r
681 .byte 0\r
682\r
683GDT_END: \r
684\r
685 .p2align 1\r
686\r
687\r
688\r
689idtr: .long IDT_END - IDT_BASE - 1 # IDT limit\r
690 .quad 0 # (IDT base gets set above)\r
691\r
692##############################################################################\r
693# interrupt descriptor table (IDT)\r
694#\r
695# Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ\r
696# mappings. This implementation only uses the system timer and all other\r
697# IRQs will remain masked. The descriptors for vectors 33+ are provided\r
698# for convenience.\r
699##############################################################################\r
700\r
701#idt_tag db "IDT",0 \r
702 .p2align 1\r
703\r
704\r
705IDT_BASE: \r
706# divide by zero (INT 0)\r
707.equ DIV_ZERO_SEL, .-IDT_BASE\r
708 .word 0 # offset 15:0\r
709 .long SYS_CODE64_SEL # selector 15:0\r
710 .byte 0 # 0 for interrupt gate\r
711 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
712 .word 0 # offset 31:16\r
713 .long 0 # offset 63:32\r
714 .long 0 # 0 for reserved\r
715\r
716# debug exception (INT 1)\r
717.equ DEBUG_EXCEPT_SEL, .-IDT_BASE\r
718 .word 0 # offset 15:0\r
719 .long SYS_CODE64_SEL # selector 15:0\r
720 .byte 0 # 0 for interrupt gate\r
721 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
722 .word 0 # offset 31:16\r
723 .long 0 # offset 63:32\r
724 .long 0 # 0 for reserved\r
725\r
726# NMI (INT 2)\r
727.equ NMI_SEL, .-IDT_BASE\r
728 .word 0 # offset 15:0\r
729 .long SYS_CODE64_SEL # selector 15:0\r
730 .byte 0 # 0 for interrupt gate\r
731 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
732 .word 0 # offset 31:16\r
733 .long 0 # offset 63:32\r
734 .long 0 # 0 for reserved\r
735\r
736# soft breakpoint (INT 3)\r
737.equ BREAKPOINT_SEL, .-IDT_BASE\r
738 .word 0 # offset 15:0\r
739 .long SYS_CODE64_SEL # selector 15:0\r
740 .byte 0 # 0 for interrupt gate\r
741 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
742 .word 0 # offset 31:16\r
743 .long 0 # offset 63:32\r
744 .long 0 # 0 for reserved\r
745\r
746# overflow (INT 4)\r
747.equ OVERFLOW_SEL, .-IDT_BASE\r
748 .word 0 # offset 15:0\r
749 .long SYS_CODE64_SEL # selector 15:0\r
750 .byte 0 # 0 for interrupt gate\r
751 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
752 .word 0 # offset 31:16\r
753 .long 0 # offset 63:32\r
754 .long 0 # 0 for reserved\r
755\r
756# bounds check (INT 5)\r
757.equ BOUNDS_CHECK_SEL, .-IDT_BASE\r
758 .word 0 # offset 15:0\r
759 .long SYS_CODE64_SEL # selector 15:0\r
760 .byte 0 # 0 for interrupt gate\r
761 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
762 .word 0 # offset 31:16\r
763 .long 0 # offset 63:32\r
764 .long 0 # 0 for reserved\r
765\r
766# invalid opcode (INT 6)\r
767.equ INVALID_OPCODE_SEL, .-IDT_BASE\r
768 .word 0 # offset 15:0\r
769 .long SYS_CODE64_SEL # selector 15:0\r
770 .byte 0 # 0 for interrupt gate\r
771 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
772 .word 0 # offset 31:16\r
773 .long 0 # offset 63:32\r
774 .long 0 # 0 for reserved\r
775\r
776# device not available (INT 7)\r
777.equ DEV_NOT_AVAIL_SEL, .-IDT_BASE\r
778 .word 0 # offset 15:0\r
779 .long SYS_CODE64_SEL # selector 15:0\r
780 .byte 0 # 0 for interrupt gate\r
781 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
782 .word 0 # offset 31:16\r
783 .long 0 # offset 63:32\r
784 .long 0 # 0 for reserved\r
785\r
786# double fault (INT 8)\r
787.equ DOUBLE_FAULT_SEL, .-IDT_BASE\r
788 .word 0 # offset 15:0\r
789 .long SYS_CODE64_SEL # selector 15:0\r
790 .byte 0 # 0 for interrupt gate\r
791 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
792 .word 0 # offset 31:16\r
793 .long 0 # offset 63:32\r
794 .long 0 # 0 for reserved\r
795\r
796# Coprocessor segment overrun - reserved (INT 9)\r
797.equ RSVD_INTR_SEL1, .-IDT_BASE\r
798 .word 0 # offset 15:0\r
799 .long SYS_CODE64_SEL # selector 15:0\r
800 .byte 0 # 0 for interrupt gate\r
801 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
802 .word 0 # offset 31:16\r
803 .long 0 # offset 63:32\r
804 .long 0 # 0 for reserved\r
805\r
806# invalid TSS (INT 0ah)\r
807.equ INVALID_TSS_SEL, .-IDT_BASE\r
808 .word 0 # offset 15:0\r
809 .long SYS_CODE64_SEL # selector 15:0\r
810 .byte 0 # 0 for interrupt gate\r
811 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
812 .word 0 # offset 31:16\r
813 .long 0 # offset 63:32\r
814 .long 0 # 0 for reserved\r
815\r
816# segment not present (INT 0bh)\r
817.equ SEG_NOT_PRESENT_SEL, .-IDT_BASE\r
818 .word 0 # offset 15:0\r
819 .long SYS_CODE64_SEL # selector 15:0\r
820 .byte 0 # 0 for interrupt gate\r
821 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
822 .word 0 # offset 31:16\r
823 .long 0 # offset 63:32\r
824 .long 0 # 0 for reserved\r
825\r
826# stack fault (INT 0ch)\r
827.equ STACK_FAULT_SEL, .-IDT_BASE\r
828 .word 0 # offset 15:0\r
829 .long SYS_CODE64_SEL # selector 15:0\r
830 .byte 0 # 0 for interrupt gate\r
831 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
832 .word 0 # offset 31:16\r
833 .long 0 # offset 63:32\r
834 .long 0 # 0 for reserved\r
835\r
836# general protection (INT 0dh)\r
837.equ GP_FAULT_SEL, .-IDT_BASE\r
838 .word 0 # offset 15:0\r
839 .long SYS_CODE64_SEL # selector 15:0\r
840 .byte 0 # 0 for interrupt gate\r
841 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
842 .word 0 # offset 31:16\r
843 .long 0 # offset 63:32\r
844 .long 0 # 0 for reserved\r
845\r
846# page fault (INT 0eh)\r
847.equ PAGE_FAULT_SEL, .-IDT_BASE\r
848 .word 0 # offset 15:0\r
849 .long SYS_CODE64_SEL # selector 15:0\r
850 .byte 0 # 0 for interrupt gate\r
851 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
852 .word 0 # offset 31:16\r
853 .long 0 # offset 63:32\r
854 .long 0 # 0 for reserved\r
855\r
856# Intel reserved - do not use (INT 0fh)\r
857.equ RSVD_INTR_SEL2, .-IDT_BASE\r
858 .word 0 # offset 15:0\r
859 .long SYS_CODE64_SEL # selector 15:0\r
860 .byte 0 # 0 for interrupt gate\r
861 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
862 .word 0 # offset 31:16\r
863 .long 0 # offset 63:32\r
864 .long 0 # 0 for reserved\r
865\r
866# floating point error (INT 10h)\r
867.equ FLT_POINT_ERR_SEL, .-IDT_BASE\r
868 .word 0 # offset 15:0\r
869 .long SYS_CODE64_SEL # selector 15:0\r
870 .byte 0 # 0 for interrupt gate\r
871 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
872 .word 0 # offset 31:16\r
873 .long 0 # offset 63:32\r
874 .long 0 # 0 for reserved\r
875\r
876# alignment check (INT 11h)\r
877.equ ALIGNMENT_CHECK_SEL, .-IDT_BASE\r
878 .word 0 # offset 15:0\r
879 .long SYS_CODE64_SEL # selector 15:0\r
880 .byte 0 # 0 for interrupt gate\r
881 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
882 .word 0 # offset 31:16\r
883 .long 0 # offset 63:32\r
884 .long 0 # 0 for reserved\r
885\r
886# machine check (INT 12h)\r
887.equ MACHINE_CHECK_SEL, .-IDT_BASE\r
888 .word 0 # offset 15:0\r
889 .long SYS_CODE64_SEL # selector 15:0\r
890 .byte 0 # 0 for interrupt gate\r
891 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
892 .word 0 # offset 31:16\r
893 .long 0 # offset 63:32\r
894 .long 0 # 0 for reserved\r
895\r
896# SIMD floating-point exception (INT 13h)\r
897.equ SIMD_EXCEPTION_SEL, .-IDT_BASE\r
898 .word 0 # offset 15:0\r
899 .long SYS_CODE64_SEL # selector 15:0\r
900 .byte 0 # 0 for interrupt gate\r
901 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
902 .word 0 # offset 31:16\r
903 .long 0 # offset 63:32\r
904 .long 0 # 0 for reserved\r
905\r
906# 85 unspecified descriptors, First 12 of them are reserved, the rest are avail\r
907 .fill 85 * 16, 1, 0 # db (85 * 16) dup(0)\r
908\r
909# IRQ 0 (System timer) - (INT 68h)\r
910.equ IRQ0_SEL, .-IDT_BASE\r
911 .word 0 # offset 15:0\r
912 .long SYS_CODE64_SEL # selector 15:0\r
913 .byte 0 # 0 for interrupt gate\r
914 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
915 .word 0 # offset 31:16\r
916 .long 0 # offset 63:32\r
917 .long 0 # 0 for reserved\r
918\r
919# IRQ 1 (8042 Keyboard controller) - (INT 69h)\r
920.equ IRQ1_SEL, .-IDT_BASE\r
921 .word 0 # offset 15:0\r
922 .long SYS_CODE64_SEL # selector 15:0\r
923 .byte 0 # 0 for interrupt gate\r
924 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
925 .word 0 # offset 31:16\r
926 .long 0 # offset 63:32\r
927 .long 0 # 0 for reserved\r
928\r
929# Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah)\r
930.equ IRQ2_SEL, .-IDT_BASE\r
931 .word 0 # offset 15:0\r
932 .long SYS_CODE64_SEL # selector 15:0\r
933 .byte 0 # 0 for interrupt gate\r
934 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
935 .word 0 # offset 31:16\r
936 .long 0 # offset 63:32\r
937 .long 0 # 0 for reserved\r
938\r
939# IRQ 3 (COM 2) - (INT 6bh)\r
940.equ IRQ3_SEL, .-IDT_BASE\r
941 .word 0 # offset 15:0\r
942 .long SYS_CODE64_SEL # selector 15:0\r
943 .byte 0 # 0 for interrupt gate\r
944 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
945 .word 0 # offset 31:16\r
946 .long 0 # offset 63:32\r
947 .long 0 # 0 for reserved\r
948\r
949# IRQ 4 (COM 1) - (INT 6ch)\r
950.equ IRQ4_SEL, .-IDT_BASE\r
951 .word 0 # offset 15:0\r
952 .long SYS_CODE64_SEL # selector 15:0\r
953 .byte 0 # 0 for interrupt gate\r
954 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
955 .word 0 # offset 31:16\r
956 .long 0 # offset 63:32\r
957 .long 0 # 0 for reserved\r
958\r
959# IRQ 5 (LPT 2) - (INT 6dh)\r
960.equ IRQ5_SEL, .-IDT_BASE\r
961 .word 0 # offset 15:0\r
962 .long SYS_CODE64_SEL # selector 15:0\r
963 .byte 0 # 0 for interrupt gate\r
964 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
965 .word 0 # offset 31:16\r
966 .long 0 # offset 63:32\r
967 .long 0 # 0 for reserved\r
968\r
969# IRQ 6 (Floppy controller) - (INT 6eh)\r
970.equ IRQ6_SEL, .-IDT_BASE\r
971 .word 0 # offset 15:0\r
972 .long SYS_CODE64_SEL # selector 15:0\r
973 .byte 0 # 0 for interrupt gate\r
974 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
975 .word 0 # offset 31:16\r
976 .long 0 # offset 63:32\r
977 .long 0 # 0 for reserved\r
978\r
979# IRQ 7 (LPT 1) - (INT 6fh)\r
980.equ IRQ7_SEL, .-IDT_BASE\r
981 .word 0 # offset 15:0\r
982 .long SYS_CODE64_SEL # selector 15:0\r
983 .byte 0 # 0 for interrupt gate\r
984 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
985 .word 0 # offset 31:16\r
986 .long 0 # offset 63:32\r
987 .long 0 # 0 for reserved\r
988\r
989# IRQ 8 (RTC Alarm) - (INT 70h)\r
990.equ IRQ8_SEL, .-IDT_BASE\r
991 .word 0 # offset 15:0\r
992 .long SYS_CODE64_SEL # selector 15:0\r
993 .byte 0 # 0 for interrupt gate\r
994 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
995 .word 0 # offset 31:16\r
996 .long 0 # offset 63:32\r
997 .long 0 # 0 for reserved\r
998\r
999# IRQ 9 - (INT 71h)\r
1000.equ IRQ9_SEL, .-IDT_BASE\r
1001 .word 0 # offset 15:0\r
1002 .long SYS_CODE64_SEL # selector 15:0\r
1003 .byte 0 # 0 for interrupt gate\r
1004 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
1005 .word 0 # offset 31:16\r
1006 .long 0 # offset 63:32\r
1007 .long 0 # 0 for reserved\r
1008\r
1009# IRQ 10 - (INT 72h)\r
1010.equ IRQ10_SEL, .-IDT_BASE\r
1011 .word 0 # offset 15:0\r
1012 .long SYS_CODE64_SEL # selector 15:0\r
1013 .byte 0 # 0 for interrupt gate\r
1014 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
1015 .word 0 # offset 31:16\r
1016 .long 0 # offset 63:32\r
1017 .long 0 # 0 for reserved\r
1018\r
1019# IRQ 11 - (INT 73h)\r
1020.equ IRQ11_SEL, .-IDT_BASE\r
1021 .word 0 # offset 15:0\r
1022 .long SYS_CODE64_SEL # selector 15:0\r
1023 .byte 0 # 0 for interrupt gate\r
1024 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
1025 .word 0 # offset 31:16\r
1026 .long 0 # offset 63:32\r
1027 .long 0 # 0 for reserved\r
1028\r
1029# IRQ 12 (PS/2 mouse) - (INT 74h)\r
1030.equ IRQ12_SEL, .-IDT_BASE\r
1031 .word 0 # offset 15:0\r
1032 .long SYS_CODE64_SEL # selector 15:0\r
1033 .byte 0 # 0 for interrupt gate\r
1034 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
1035 .word 0 # offset 31:16\r
1036 .long 0 # offset 63:32\r
1037 .long 0 # 0 for reserved\r
1038\r
1039# IRQ 13 (Floating point error) - (INT 75h)\r
1040.equ IRQ13_SEL, .-IDT_BASE\r
1041 .word 0 # offset 15:0\r
1042 .long SYS_CODE64_SEL # selector 15:0\r
1043 .byte 0 # 0 for interrupt gate\r
1044 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
1045 .word 0 # offset 31:16\r
1046 .long 0 # offset 63:32\r
1047 .long 0 # 0 for reserved\r
1048\r
1049# IRQ 14 (Secondary IDE) - (INT 76h)\r
1050.equ IRQ14_SEL, .-IDT_BASE\r
1051 .word 0 # offset 15:0\r
1052 .long SYS_CODE64_SEL # selector 15:0\r
1053 .byte 0 # 0 for interrupt gate\r
1054 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
1055 .word 0 # offset 31:16\r
1056 .long 0 # offset 63:32\r
1057 .long 0 # 0 for reserved\r
1058\r
1059# IRQ 15 (Primary IDE) - (INT 77h)\r
1060.equ IRQ15_SEL, .-IDT_BASE\r
1061 .word 0 # offset 15:0\r
1062 .long SYS_CODE64_SEL # selector 15:0\r
1063 .byte 0 # 0 for interrupt gate\r
1064 .byte 0x0e | 0x80 # type = 386 interrupt gate, present\r
1065 .word 0 # offset 31:16\r
1066 .long 0 # offset 63:32\r
1067 .long 0 # 0 for reserved\r
1068\r
1069IDT_END: \r
1070\r
1071 .p2align 1\r
1072\r
1073MemoryMapSize: .long 0\r
1074MemoryMap: .long 0,0,0,0,0,0,0,0\r
1075 .long 0,0,0,0,0,0,0,0\r
1076 .long 0,0,0,0,0,0,0,0\r
1077 .long 0,0,0,0,0,0,0,0\r
1078 .long 0,0,0,0,0,0,0,0\r
1079 .long 0,0,0,0,0,0,0,0\r
1080 .long 0,0,0,0,0,0,0,0\r
1081 .long 0,0,0,0,0,0,0,0\r
1082 .long 0,0,0,0,0,0,0,0\r
1083 .long 0,0,0,0,0,0,0,0\r
1084 .long 0,0,0,0,0,0,0,0\r
1085 .long 0,0,0,0,0,0,0,0\r
1086 .long 0,0,0,0,0,0,0,0\r
1087 .long 0,0,0,0,0,0,0,0\r
1088 .long 0,0,0,0,0,0,0,0\r
1089 .long 0,0,0,0,0,0,0,0\r
1090 .long 0,0,0,0,0,0,0,0\r
1091 .long 0,0,0,0,0,0,0,0\r
1092 .long 0,0,0,0,0,0,0,0\r
1093 .long 0,0,0,0,0,0,0,0\r
1094 .long 0,0,0,0,0,0,0,0\r
1095 .long 0,0,0,0,0,0,0,0\r
1096 .long 0,0,0,0,0,0,0,0\r
1097 .long 0,0,0,0,0,0,0,0\r
1098 .long 0,0,0,0,0,0,0,0\r
1099 .long 0,0,0,0,0,0,0,0\r
1100 .long 0,0,0,0,0,0,0,0\r
1101 .long 0,0,0,0,0,0,0,0\r
1102 .long 0,0,0,0,0,0,0,0\r
1103 .long 0,0,0,0,0,0,0,0\r
1104\r
1105 .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\r
1106\r
1107 .org 0x0fe0\r
1108MyStack: \r
1109 # below is the pieces of the IVT that is used to redirect INT 68h - 6fh\r
1110 # back to INT 08h - 0fh when in real mode... It is 'org'ed to a\r
1111 # known low address (20f00) so it can be set up by PlMapIrqToVect in\r
1112 # 8259.c\r
1113\r
1114 int $8\r
1115 iret\r
1116\r
1117 int $9\r
1118 iret\r
1119\r
1120 int $10\r
1121 iret\r
1122\r
1123 int $11\r
1124 iret\r
1125\r
1126 int $12\r
1127 iret\r
1128\r
1129 int $13\r
1130 iret\r
1131\r
1132 int $14\r
1133 iret\r
1134\r
1135 int $15\r
1136 iret\r
1137\r
1138\r
1139 .org 0x0ffe\r
1140BlockSignature: \r
1141 .word 0xaa55\r
1142\r