1 #------------------------------------------------------------------------------
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
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.
16 #------------------------------------------------------------------------------
23 .equ FAT_DIRECTORY_ENTRY_SIZE, 0x020
24 .equ FAT_DIRECTORY_ENTRY_SHIFT, 5
25 .equ BLOCK_SIZE, 0x0200
26 .equ BLOCK_MASK, 0x01ff
35 jmp BootSectorEntryPoint # JMP inst - 3 bytes
38 OemId: .ascii "INTEL " # OemId - 8 bytes
39 SectorSize: .word 0 # Sector Size - 2 bytes
40 SectorsPerCluster: .byte 0 # Sector Per Cluster - 1 byte
41 ReservedSectors: .word 0 # Reserved Sectors - 2 bytes
42 NoFats: .byte 0 # Number of FATs - 1 byte
43 RootEntries: .word 0 # Root Entries - 2 bytes
44 Sectors: .word 0 # Number of Sectors - 2 bytes
45 Media: .byte 0 # Media - 1 byte
46 SectorsPerFat16: .word 0 # Sectors Per FAT for FAT12/FAT16 - 2 byte
47 SectorsPerTrack: .word 0 # Sectors Per Track - 2 bytes
48 Heads: .word 0 # Heads - 2 bytes
49 HiddenSectors: .long 0 # Hidden Sectors - 4 bytes
50 LargeSectors: .long 0 # Large Sectors - 4 bytes
52 #******************************************************************************
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.)
57 #******************************************************************************
59 SectorsPerFat32: .long 0 # Sectors Per FAT for FAT32 - 4 bytes
60 ExtFlags: .word 0 # Mirror Flag - 2 bytes
61 FSVersion: .word 0 # File System Version - 2 bytes
62 RootCluster: .long 0 # 1st Cluster Number of Root Dir - 4 bytes
63 FSInfo: .word 0 # Sector Number of FSINFO - 2 bytes
64 BkBootSector: .word 0 # Sector Number of Bk BootSector - 2 bytes
65 Reserved: .fill 12,1,0 # Reserved Field - 12 bytes
66 PhysicalDrive: .byte 0 # Physical Drive Number - 1 byte
67 Reserved1: .byte 0 # Reserved Field - 1 byte
68 Signature: .byte 0 # Extended Boot Signature - 1 byte
69 VolId: .ascii " " # Volume Serial Number - 4 bytes
70 FatLabel: .ascii " " # Volume Label - 11 bytes
71 FileSystemType: .ascii "FAT32 " # File System Type - 8 bytes
76 # ds = 1000, es = 2000 + x (size of first cluster >> 4)
77 # cx = Start Cluster of EfiLdr
78 # dx = Start Cluster of Efivar.bin
80 # Re use the BPB data stored in Boot Sector
86 # 1000:dx = DirectoryEntry of Efivar.bin -> BS.com has filled already
95 # Set the 5th byte start @ 0:19000 to non-zero indicating we should init var store header in DxeIpl
101 cmpl $0x4000, %ds:2(%di)
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
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
131 movw %ax, %cs:JumpSegment
142 # ****************************************************************************
146 # CX = Start Cluster of File
147 # ES:DI = Buffer to store file content read from disk
150 # (ES << 4 + DI) = end of file content Buffer
152 # ****************************************************************************
154 # si = NumberOfClusters
156 # dx = CachedFatSectorNumber
157 # ds:0000 = CacheFatSectorBuffer
158 # es:di = Buffer to load file
159 # bx = NextClusterNumber
161 movw $1, %si # NumberOfClusters = 1
162 pushw %cx # Push Start Cluster onto stack
163 movw $0xfff, %dx # CachedFatSectorNumber = 0xfff
165 movw %cx, %ax # ax = ClusterNumber
166 andw $0xfff8, %ax # ax = ax & 0xfff8
167 cmpw $0xfff8, %ax # See if this is the last cluster
168 je FoundLastCluster # Jump if last cluster found
169 movw %cx, %ax # ax = ClusterNumber
170 shlw $2, %ax # FatOffset = ClusterNumber * 4
172 movw %ax, %si # si = FatOffset
173 shrw $BLOCK_SHIFT, %ax # ax = FatOffset >> BLOCK_SHIFT
174 addw ReservedSectors(%bp), %ax # ax = FatSectorNumber = ReservedSectors + (FatOffset >> BLOCK_OFFSET)
175 andw $BLOCK_MASK, %si # si = FatOffset & BLOCK_MASK
176 cmpw %dx, %ax # Compare FatSectorNumber to CachedFatSectorNumber
182 call ReadBlocks # Read 2 blocks starting at AX storing at ES:DI
184 movw %ax, %dx # CachedFatSectorNumber = FatSectorNumber
186 movw (%si), %bx # bx = NextClusterNumber
187 movw %cx, %ax # ax = ClusterNumber
188 popw %si # Restore si
189 decw %bx # bx = NextClusterNumber - 1
190 cmpw %cx, %bx # See if (NextClusterNumber-1)==ClusterNumber
192 incw %bx # bx = NextClusterNumber
193 incw %si # NumberOfClusters++
194 movw %bx, %cx # ClusterNumber = NextClusterNumber
198 popw %ax # ax = StartCluster
199 pushw %bx # StartCluster = NextClusterNumber
200 movw %bx, %cx # ClusterNumber = NextClusterNumber
201 subw $2, %ax # ax = StartCluster - 2
203 movb SectorsPerCluster(%bp), %bl # bx = SectorsPerCluster
204 mulw %bx # ax = (StartCluster - 2) * SectorsPerCluster
205 addw (%bp), %ax # ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster
206 pushw %ax # save start sector
207 movw %si, %ax # ax = NumberOfClusters
208 mulw %bx # ax = NumberOfClusters * SectorsPerCluster
209 movw %ax, %bx # bx = Number of Sectors
210 popw %ax # ax = Start Sector
212 movw $1, %si # NumberOfClusters = 1
220 # ****************************************************************************
221 # ReadBlocks - Reads a set of blocks from a block device
224 # BX = Number of Blocks to Read
225 # ES:DI = Buffer to store sectors read from disk
226 # ****************************************************************************
229 # bx = NumberOfBlocks
234 addl LBAOffsetForBootSector(%bp), %eax # Add LBAOffsetForBootSector to Start LBA
235 addl HiddenSectors(%bp), %eax # Add HiddenSectors to Start LBA
236 movl %eax, %esi # esi = Start LBA
237 movw %bx, %cx # cx = Number of blocks to read
239 movw $0x7bfc, %bp # bp = 0x7bfc
240 movl %esi, %eax # eax = Start LBA
241 xorl %edx, %edx # edx = 0
242 movzwl (%bp), %ebx # bx = MaxSector
243 divl %ebx # ax = StartLBA / MaxSector
244 incw %dx # dx = (StartLBA % MaxSector) + 1
246 movw (%bp), %bx # bx = MaxSector
247 subw %dx, %bx # bx = MaxSector - Sector
248 incw %bx # bx = MaxSector - Sector + 1
249 cmpw %bx, %cx # Compare (Blocks) to (MaxSector - Sector + 1)
251 movw %cx, %bx # bx = Blocks
254 movw %es, %ax # ax = es
255 shrw $(BLOCK_SHIFT-4), %ax # ax = Number of blocks into mem system
256 andw $0x7f, %ax # ax = Number of blocks into current seg
257 addw %bx, %ax # ax = End Block number of transfer
258 cmpw $0x80, %ax # See if it crosses a 64K boundry
259 jle NotCrossing64KBoundry # Branch if not crossing 64K boundry
260 subw $0x80, %ax # ax = Number of blocks past 64K boundry
261 subw %ax, %bx # Decrease transfer size by block overage
262 NotCrossing64KBoundry:
263 popw %ax # restore ax
266 movb %dl, %cl # cl = (StartLBA % MaxSector) + 1 = Sector
267 xorw %dx, %dx # dx = 0
268 divw 2(%bp) # ax = ax / (MaxHead + 1) = Cylinder
269 # dx = ax % (MaxHead + 1) = Head
271 pushw %bx # Save number of blocks to transfer
272 movb %dl, %dh # dh = Head
273 movw $0x7c00, %bp # bp = 0x7c00
274 movb PhysicalDrive(%bp), %dl # dl = Drive Number
275 movb %al, %ch # ch = Cylinder
276 movb %bl, %al # al = Blocks
277 movb $2, %ah # ah = Function 2
278 movw %di, %bx # es:bx = Buffer address
284 addl %ebx, %esi # StartLBA = StartLBA + NumberOfBlocks
285 subw %bx, %cx # Blocks = Blocks - NumberOfBlocks
287 shlw $(BLOCK_SHIFT-4), %bx
289 movw %ax, %es # es:di = es:di + NumberOfBlocks*BLOCK_SIZE
298 leaw ErrorString, %si
300 jmp PrintStringAndHalt
312 .byte 'S', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, 'o', 0x0c, 'r', 0x0c, '!', 0x0c
314 # .org 0x01fa # Will cause build break
315 LBAOffsetForBootSector:
318 # .org 0x01fe # Will cause build break
321 #******************************************************************************
322 #******************************************************************************
323 #******************************************************************************
325 .equ DELAY_PORT, 0x0ed # Port to use for 1uS delay
326 .equ KBD_CONTROL_PORT, 0x060 # 8042 control port
327 .equ KBD_STATUS_PORT, 0x064 # 8042 status port
328 .equ WRITE_DATA_PORT_CMD, 0x0d1 # 8042 command to write the data port
329 .equ ENABLE_A20_CMD, 0x0df # 8042 command to enable A20
331 # .org 0x200 # Will cause build break
334 .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
345 # mov byte ptr es:[160],'a'
354 movl $0x534d4150, %edx # 0x534d4150 = 'SMAP'
363 subl %eax, %edi # Get the address of the memory map
364 movl %edi, MemoryMapSize # Save the size of the memory map
367 movw %cs, %bx # BX=segment
368 shll $4, %ebx # BX="linear" address of segment base
369 leal GDT_BASE(%ebx), %eax # EAX=PHYSICAL address of gdt
370 movl %eax, gdtr + 2 # Put address of gdt into the gdtr
371 leal IDT_BASE(%ebx), %eax # EAX=PHYSICAL address of idt
372 movl %eax, idtr + 2 # Put address of idt into the idtr
373 leal MemoryMapSize(%ebx), %edx # Physical base address of the memory map
375 addl $0x1000, %ebx # Source of EFI32
378 movl %ebx, %esi # Source of EFILDR32
382 # mov byte ptr es:[162],'b'
390 movw $0x2401, %ax # Enable A20 Gate
392 jnc A20GateEnabled # Jump if it suceeded
395 # If INT 15 Function 2401 is not supported, then attempt to Enable A20 manually.
398 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller
399 jnz Timeout8042 # Jump if the 8042 timed out
400 outw %ax, $DELAY_PORT # Delay 1 uS
401 movb $WRITE_DATA_PORT_CMD, %al # 8042 cmd to write output port
402 outb %al, $KBD_STATUS_PORT # Send command to the 8042
403 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller
404 jnz Timeout8042 # Jump if the 8042 timed out
405 movb $ENABLE_A20_CMD, %al # gate address bit 20 on
406 outb %al, $KBD_CONTROL_PORT # Send command to thre 8042
407 call Empty8042InputBuffer # Empty the Input Buffer on the 8042 controller
408 movw $25, %cx # Delay 25 uS for the command to complete on the 8042
410 outw %ax, $DELAY_PORT # Delay 1 uS
418 # DISABLE INTERRUPTS - Entering Protected Mode
425 # mov byte ptr es:[164],'c'
438 movl $0x008, %eax # Flat data descriptor
439 movl $0x00400000, %ebp # Destination of EFILDR32
440 movl $0x00070000, %ebx # Length of copy
443 # jmp far 0010:00020000
449 Empty8042InputBuffer:
452 outw %ax, $DELAY_PORT # Delay 1us
453 inb $KBD_STATUS_PORT, %al # Read the 8042 Status Port
454 andb $0x2, %al # Check the Input Buffer Full Flag
455 loopnz Empty8042Loop # Loop until the input buffer is empty or a timout of 65536 uS
458 ##############################################################################
460 ##############################################################################
464 gdtr: .word GDT_END - GDT_BASE - 1
465 .long 0 # (GDT base gets set above)
466 ##############################################################################
467 # global descriptor table (GDT)
468 ##############################################################################
474 .equ NULL_SEL, .-GDT_BASE
479 .byte 0 # limit 19:16, flags
482 # linear data segment descriptor
483 .equ LINEAR_SEL, .-GDT_BASE
484 .word 0xFFFF # limit 0xFFFFF
487 .byte 0x92 # present, ring 0, data, expand-up, writable
488 .byte 0xCF # page-granular, 32-bit
491 # linear code segment descriptor
492 .equ LINEAR_CODE_SEL, .-GDT_BASE
493 .word 0xFFFF # limit 0xFFFFF
496 .byte 0x9A # present, ring 0, data, expand-up, writable
497 .byte 0xCF # page-granular, 32-bit
500 # system data segment descriptor
501 .equ SYS_DATA_SEL, .-GDT_BASE
502 .word 0xFFFF # limit 0xFFFFF
505 .byte 0x92 # present, ring 0, data, expand-up, writable
506 .byte 0xCF # page-granular, 32-bit
509 # system code segment descriptor
510 .equ SYS_CODE_SEL, .-GDT_BASE
511 .word 0xFFFF # limit 0xFFFFF
514 .byte 0x9A # present, ring 0, data, expand-up, writable
515 .byte 0xCF # page-granular, 32-bit
518 # spare segment descriptor
519 .equ SPARE3_SEL, .-GDT_BASE
520 .word 0 # limit 0xFFFFF
523 .byte 0 # present, ring 0, data, expand-up, writable
524 .byte 0 # page-granular, 32-bit
527 # spare segment descriptor
528 .equ SPARE4_SEL, .-GDT_BASE
529 .word 0 # limit 0xFFFFF
532 .byte 0 # present, ring 0, data, expand-up, writable
533 .byte 0 # page-granular, 32-bit
536 # spare segment descriptor
537 .equ SPARE5_SEL, .-GDT_BASE
538 .word 0 # limit 0xFFFFF
541 .byte 0 # present, ring 0, data, expand-up, writable
542 .byte 0 # page-granular, 32-bit
551 idtr: .word IDT_END - IDT_BASE - 1
552 .long 0 # (IDT base gets set above)
553 ##############################################################################
554 # interrupt descriptor table (IDT)
556 # Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ
557 # mappings. This implementation only uses the system timer and all other
558 # IRQs will remain masked. The descriptors for vectors 33+ are provided
560 ##############################################################################
566 # divide by zero (INT 0)
567 .equ DIV_ZERO_SEL, .-IDT_BASE
568 .word 0 # offset 15:0
569 .word SYS_CODE_SEL # selector 15:0
570 .byte 0 # 0 for interrupt gate
571 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
572 .word 0 # offset 31:16
574 # debug exception (INT 1)
575 .equ DEBUG_EXCEPT_SEL, .-IDT_BASE
576 .word 0 # offset 15:0
577 .word SYS_CODE_SEL # selector 15:0
578 .byte 0 # 0 for interrupt gate
579 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
580 .word 0 # offset 31:16
583 .equ NMI_SEL, .-IDT_BASE
584 .word 0 # offset 15:0
585 .word SYS_CODE_SEL # selector 15:0
586 .byte 0 # 0 for interrupt gate
587 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
588 .word 0 # offset 31:16
590 # soft breakpoint (INT 3)
591 .equ BREAKPOINT_SEL, .-IDT_BASE
592 .word 0 # offset 15:0
593 .word SYS_CODE_SEL # selector 15:0
594 .byte 0 # 0 for interrupt gate
595 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
596 .word 0 # offset 31:16
599 .equ OVERFLOW_SEL, .-IDT_BASE
600 .word 0 # offset 15:0
601 .word SYS_CODE_SEL # selector 15:0
602 .byte 0 # 0 for interrupt gate
603 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
604 .word 0 # offset 31:16
606 # bounds check (INT 5)
607 .equ BOUNDS_CHECK_SEL, .-IDT_BASE
608 .word 0 # offset 15:0
609 .word SYS_CODE_SEL # selector 15:0
610 .byte 0 # 0 for interrupt gate
611 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
612 .word 0 # offset 31:16
614 # invalid opcode (INT 6)
615 .equ INVALID_OPCODE_SEL, .-IDT_BASE
616 .word 0 # offset 15:0
617 .word SYS_CODE_SEL # selector 15:0
618 .byte 0 # 0 for interrupt gate
619 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
620 .word 0 # offset 31:16
622 # device not available (INT 7)
623 .equ DEV_NOT_AVAIL_SEL, .-IDT_BASE
624 .word 0 # offset 15:0
625 .word SYS_CODE_SEL # selector 15:0
626 .byte 0 # 0 for interrupt gate
627 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
628 .word 0 # offset 31:16
630 # double fault (INT 8)
631 .equ DOUBLE_FAULT_SEL, .-IDT_BASE
632 .word 0 # offset 15:0
633 .word SYS_CODE_SEL # selector 15:0
634 .byte 0 # 0 for interrupt gate
635 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
636 .word 0 # offset 31:16
638 # Coprocessor segment overrun - reserved (INT 9)
639 .equ RSVD_INTR_SEL1, .-IDT_BASE
640 .word 0 # offset 15:0
641 .word SYS_CODE_SEL # selector 15:0
642 .byte 0 # 0 for interrupt gate
643 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
644 .word 0 # offset 31:16
646 # invalid TSS (INT 0ah)
647 .equ INVALID_TSS_SEL, .-IDT_BASE
648 .word 0 # offset 15:0
649 .word SYS_CODE_SEL # selector 15:0
650 .byte 0 # 0 for interrupt gate
651 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
652 .word 0 # offset 31:16
654 # segment not present (INT 0bh)
655 .equ SEG_NOT_PRESENT_SEL, .-IDT_BASE
656 .word 0 # offset 15:0
657 .word SYS_CODE_SEL # selector 15:0
658 .byte 0 # 0 for interrupt gate
659 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
660 .word 0 # offset 31:16
662 # stack fault (INT 0ch)
663 .equ STACK_FAULT_SEL, .-IDT_BASE
664 .word 0 # offset 15:0
665 .word SYS_CODE_SEL # selector 15:0
666 .byte 0 # 0 for interrupt gate
667 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
668 .word 0 # offset 31:16
670 # general protection (INT 0dh)
671 .equ GP_FAULT_SEL, .-IDT_BASE
672 .word 0 # offset 15:0
673 .word SYS_CODE_SEL # selector 15:0
674 .byte 0 # 0 for interrupt gate
675 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
676 .word 0 # offset 31:16
678 # page fault (INT 0eh)
679 .equ PAGE_FAULT_SEL, .-IDT_BASE
680 .word 0 # offset 15:0
681 .word SYS_CODE_SEL # selector 15:0
682 .byte 0 # 0 for interrupt gate
683 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
684 .word 0 # offset 31:16
686 # Intel reserved - do not use (INT 0fh)
687 .equ RSVD_INTR_SEL2, .-IDT_BASE
688 .word 0 # offset 15:0
689 .word SYS_CODE_SEL # selector 15:0
690 .byte 0 # 0 for interrupt gate
691 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
692 .word 0 # offset 31:16
694 # floating point error (INT 10h)
695 .equ FLT_POINT_ERR_SEL, .-IDT_BASE
696 .word 0 # offset 15:0
697 .word SYS_CODE_SEL # selector 15:0
698 .byte 0 # 0 for interrupt gate
699 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
700 .word 0 # offset 31:16
702 # alignment check (INT 11h)
703 .equ ALIGNMENT_CHECK_SEL, .-IDT_BASE
704 .word 0 # offset 15:0
705 .word SYS_CODE_SEL # selector 15:0
706 .byte 0 # 0 for interrupt gate
707 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
708 .word 0 # offset 31:16
710 # machine check (INT 12h)
711 .equ MACHINE_CHECK_SEL, .-IDT_BASE
712 .word 0 # offset 15:0
713 .word SYS_CODE_SEL # selector 15:0
714 .byte 0 # 0 for interrupt gate
715 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
716 .word 0 # offset 31:16
718 # SIMD floating-point exception (INT 13h)
719 .equ SIMD_EXCEPTION_SEL, .-IDT_BASE
720 .word 0 # offset 15:0
721 .word SYS_CODE_SEL # selector 15:0
722 .byte 0 # 0 for interrupt gate
723 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
724 .word 0 # offset 31:16
726 # 85 unspecified descriptors, First 12 of them are reserved, the rest are avail
729 # IRQ 0 (System timer) - (INT 68h)
730 .equ IRQ0_SEL, .-IDT_BASE
731 .word 0 # offset 15:0
732 .word SYS_CODE_SEL # selector 15:0
733 .byte 0 # 0 for interrupt gate
734 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
735 .word 0 # offset 31:16
737 # IRQ 1 (8042 Keyboard controller) - (INT 69h)
738 .equ IRQ1_SEL, .-IDT_BASE
739 .word 0 # offset 15:0
740 .word SYS_CODE_SEL # selector 15:0
741 .byte 0 # 0 for interrupt gate
742 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
743 .word 0 # offset 31:16
745 # Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah)
746 .equ IRQ2_SEL, .-IDT_BASE
747 .word 0 # offset 15:0
748 .word SYS_CODE_SEL # selector 15:0
749 .byte 0 # 0 for interrupt gate
750 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
751 .word 0 # offset 31:16
753 # IRQ 3 (COM 2) - (INT 6bh)
754 .equ IRQ3_SEL, .-IDT_BASE
755 .word 0 # offset 15:0
756 .word SYS_CODE_SEL # selector 15:0
757 .byte 0 # 0 for interrupt gate
758 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
759 .word 0 # offset 31:16
761 # IRQ 4 (COM 1) - (INT 6ch)
762 .equ IRQ4_SEL, .-IDT_BASE
763 .word 0 # offset 15:0
764 .word SYS_CODE_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
769 # IRQ 5 (LPT 2) - (INT 6dh)
770 .equ IRQ5_SEL, .-IDT_BASE
771 .word 0 # offset 15:0
772 .word SYS_CODE_SEL # selector 15:0
773 .byte 0 # 0 for interrupt gate
774 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
775 .word 0 # offset 31:16
777 # IRQ 6 (Floppy controller) - (INT 6eh)
778 .equ IRQ6_SEL, .-IDT_BASE
779 .word 0 # offset 15:0
780 .word SYS_CODE_SEL # selector 15:0
781 .byte 0 # 0 for interrupt gate
782 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
783 .word 0 # offset 31:16
785 # IRQ 7 (LPT 1) - (INT 6fh)
786 .equ IRQ7_SEL, .-IDT_BASE
787 .word 0 # offset 15:0
788 .word SYS_CODE_SEL # selector 15:0
789 .byte 0 # 0 for interrupt gate
790 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
791 .word 0 # offset 31:16
793 # IRQ 8 (RTC Alarm) - (INT 70h)
794 .equ IRQ8_SEL, .-IDT_BASE
795 .word 0 # offset 15:0
796 .word SYS_CODE_SEL # selector 15:0
797 .byte 0 # 0 for interrupt gate
798 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
799 .word 0 # offset 31:16
802 .equ IRQ9_SEL, .-IDT_BASE
803 .word 0 # offset 15:0
804 .word SYS_CODE_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
810 .equ IRQ10_SEL, .-IDT_BASE
811 .word 0 # offset 15:0
812 .word SYS_CODE_SEL # selector 15:0
813 .byte 0 # 0 for interrupt gate
814 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
815 .word 0 # offset 31:16
818 .equ IRQ11_SEL, .-IDT_BASE
819 .word 0 # offset 15:0
820 .word SYS_CODE_SEL # selector 15:0
821 .byte 0 # 0 for interrupt gate
822 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
823 .word 0 # offset 31:16
825 # IRQ 12 (PS/2 mouse) - (INT 74h)
826 .equ IRQ12_SEL, .-IDT_BASE
827 .word 0 # offset 15:0
828 .word SYS_CODE_SEL # selector 15:0
829 .byte 0 # 0 for interrupt gate
830 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
831 .word 0 # offset 31:16
833 # IRQ 13 (Floating point error) - (INT 75h)
834 .equ IRQ13_SEL, .-IDT_BASE
835 .word 0 # offset 15:0
836 .word SYS_CODE_SEL # selector 15:0
837 .byte 0 # 0 for interrupt gate
838 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
839 .word 0 # offset 31:16
841 # IRQ 14 (Secondary IDE) - (INT 76h)
842 .equ IRQ14_SEL, .-IDT_BASE
843 .word 0 # offset 15:0
844 .word SYS_CODE_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
849 # IRQ 15 (Primary IDE) - (INT 77h)
850 .equ IRQ15_SEL, .-IDT_BASE
851 .word 0 # offset 15:0
852 .word SYS_CODE_SEL # selector 15:0
853 .byte 0 # 0 for interrupt gate
854 .byte 0x0e | 0x80 # type = 386 interrupt gate, present
855 .word 0 # offset 31:16
861 MemoryMapSize: .long 0
862 MemoryMap: .long 0,0,0,0,0,0,0,0
863 .long 0,0,0,0,0,0,0,0
864 .long 0,0,0,0,0,0,0,0
865 .long 0,0,0,0,0,0,0,0
866 .long 0,0,0,0,0,0,0,0
867 .long 0,0,0,0,0,0,0,0
868 .long 0,0,0,0,0,0,0,0
869 .long 0,0,0,0,0,0,0,0
870 .long 0,0,0,0,0,0,0,0
871 .long 0,0,0,0,0,0,0,0
872 .long 0,0,0,0,0,0,0,0
873 .long 0,0,0,0,0,0,0,0
874 .long 0,0,0,0,0,0,0,0
875 .long 0,0,0,0,0,0,0,0
876 .long 0,0,0,0,0,0,0,0
877 .long 0,0,0,0,0,0,0,0
878 .long 0,0,0,0,0,0,0,0
879 .long 0,0,0,0,0,0,0,0
880 .long 0,0,0,0,0,0,0,0
881 .long 0,0,0,0,0,0,0,0
882 .long 0,0,0,0,0,0,0,0
883 .long 0,0,0,0,0,0,0,0
884 .long 0,0,0,0,0,0,0,0
885 .long 0,0,0,0,0,0,0,0
886 .long 0,0,0,0,0,0,0,0
887 .long 0,0,0,0,0,0,0,0
888 .long 0,0,0,0,0,0,0,0
889 .long 0,0,0,0,0,0,0,0
890 .long 0,0,0,0,0,0,0,0
891 .long 0,0,0,0,0,0,0,0
893 .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
894 .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
898 # below is the pieces of the IVT that is used to redirect INT 68h - 6fh
899 # back to INT 08h - 0fh when in real mode... It is 'org'ed to a
900 # known low address (20f00) so it can be set up by PlMapIrqToVect in