1 ;------------------------------------------------------------------------------
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
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 FAT_DIRECTORY_ENTRY_SIZE EQU 020h
24 FAT_DIRECTORY_ENTRY_SHIFT EQU 5
31 jmp BootSectorEntryPoint ; JMP inst - 3 bytes
34 OemId db "INTEL " ; OemId - 8 bytes
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 "FAT16 " ; SystemId - 8 bytes
58 ; ds = 1000, es = 2000 + x (size of first cluster >> 4)
59 ; cx = Start Cluster of EfiLdr
60 ; dx = Start Cluster of Efivar.bin
62 ; Re use the BPB data stored in Boot Sector
67 ; 1000:dx = DirectoryEntry of Efivar.bin -> BS.com has filled already
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
82 cmp dword ptr ds:[di+2], 04000h
88 mov byte ptr es:[4],al
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
105 ; cx = Start Cluster of Efildr -> BS.com has filled already
106 ; ES:DI = 2000:0, first cluster will be read again
112 mov word ptr cs:[JumpSegment],ax
123 ; ****************************************************************************
127 ; CX = Start Cluster of File
128 ; ES:DI = Buffer to store file content read from disk
131 ; (ES << 4 + DI) = end of file content Buffer
133 ; ****************************************************************************
135 ; si = NumberOfClusters
137 ; dx = CachedFatSectorNumber
138 ; ds:0000 = CacheFatSectorBuffer
139 ; es:di = Buffer to load file
140 ; bx = NextClusterNumber
142 mov si,1 ; NumberOfClusters = 1
143 push cx ; Push Start Cluster onto stack
144 mov dx,0fffh ; CachedFatSectorNumber = 0xfff
146 mov ax,cx ; ax = ClusterNumber
147 and ax,0fff8h ; ax = ax & 0xfff8
148 cmp ax,0fff8h ; 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 ; FatOffset = ClusterNumber * 2
153 mov si,ax ; si = FatOffset
154 shr ax,BLOCK_SHIFT ; ax = FatOffset >> BLOCK_SHIFT
155 add ax,word ptr [bp+ReservedSectors] ; ax = FatSectorNumber = ReservedSectors + (FatOffset >> BLOCK_OFFSET)
156 and si,BLOCK_MASK ; si = FatOffset & BLOCK_MASK
157 cmp ax,dx ; Compare FatSectorNumber to CachedFatSectorNumber
163 call ReadBlocks ; Read 2 blocks starting at AX storing at ES:DI
165 mov dx,ax ; CachedFatSectorNumber = FatSectorNumber
167 mov bx,word ptr [si] ; bx = NextClusterNumber
168 mov ax,cx ; ax = ClusterNumber
170 dec bx ; bx = NextClusterNumber - 1
171 cmp bx,cx ; See if (NextClusterNumber-1)==ClusterNumber
173 inc bx ; bx = NextClusterNumber
174 inc si ; NumberOfClusters++
175 mov cx,bx ; ClusterNumber = NextClusterNumber
179 pop ax ; ax = StartCluster
180 push bx ; StartCluster = NextClusterNumber
181 mov cx,bx ; ClusterNumber = NextClusterNumber
182 sub ax,2 ; ax = StartCluster - 2
184 mov bl,byte ptr [bp+SectorsPerCluster] ; bx = SectorsPerCluster
185 mul bx ; ax = (StartCluster - 2) * SectorsPerCluster
186 add ax, word ptr [bp] ; ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster
187 push ax ; save start sector
188 mov ax,si ; ax = NumberOfClusters
189 mul bx ; ax = NumberOfClusters * SectorsPerCluster
190 mov bx,ax ; bx = Number of Sectors
191 pop ax ; ax = Start Sector
193 mov si,1 ; NumberOfClusters = 1
201 ; ****************************************************************************
202 ; ReadBlocks - Reads a set of blocks from a block device
205 ; BX = Number of Blocks to Read
206 ; ES:DI = Buffer to store sectors read from disk
207 ; ****************************************************************************
210 ; bx = NumberOfBlocks
215 add eax,dword ptr [bp+LBAOffsetForBootSector] ; Add LBAOffsetForBootSector to Start LBA
216 add eax,dword ptr [bp+HiddenSectors] ; Add HiddenSectors to Start LBA
217 mov esi,eax ; esi = Start LBA
218 mov cx,bx ; cx = Number of blocks to read
220 mov bp,07bfch ; bp = 0x7bfc
221 mov eax,esi ; eax = Start LBA
222 xor edx,edx ; edx = 0
223 movzx ebx,word ptr [bp] ; bx = MaxSector
224 div ebx ; ax = StartLBA / MaxSector
225 inc dx ; dx = (StartLBA % MaxSector) + 1
227 mov bx,word ptr [bp] ; bx = MaxSector
228 sub bx,dx ; bx = MaxSector - Sector
229 inc bx ; bx = MaxSector - Sector + 1
230 cmp cx,bx ; Compare (Blocks) to (MaxSector - Sector + 1)
232 mov bx,cx ; bx = Blocks
236 shr ax,(BLOCK_SHIFT-4) ; ax = Number of blocks into mem system
237 and ax,07fh ; ax = Number of blocks into current seg
238 add ax,bx ; ax = End Block number of transfer
239 cmp ax,080h ; See if it crosses a 64K boundry
240 jle NotCrossing64KBoundry ; Branch if not crossing 64K boundry
241 sub ax,080h ; ax = Number of blocks past 64K boundry
242 sub bx,ax ; Decrease transfer size by block overage
243 NotCrossing64KBoundry:
247 mov cl,dl ; cl = (StartLBA % MaxSector) + 1 = Sector
249 div word ptr [bp+2] ; ax = ax / (MaxHead + 1) = Cylinder
250 ; dx = ax % (MaxHead + 1) = Head
252 push bx ; Save number of blocks to transfer
253 mov dh,dl ; dh = Head
254 mov bp,07c00h ; bp = 0x7c00
255 mov dl,byte ptr [bp+PhysicalDrive] ; dl = Drive Number
256 mov ch,al ; ch = Cylinder
257 mov al,bl ; al = Blocks
258 mov ah,2 ; ah = Function 2
259 mov bx,di ; es:bx = Buffer address
265 add esi,ebx ; StartLBA = StartLBA + NumberOfBlocks
266 sub cx,bx ; Blocks = Blocks - NumberOfBlocks
268 shl bx,(BLOCK_SHIFT-4)
270 mov es,ax ; es:di = es:di + NumberOfBlocks*BLOCK_SIZE
279 lea si, [ErrorString]
281 jmp PrintStringAndHalt
292 db 'S', 0ch, 'E', 0ch, 'r', 0ch, 'r', 0ch, 'o', 0ch, 'r', 0ch, '!', 0ch
295 LBAOffsetForBootSector:
301 ;******************************************************************************
302 ;******************************************************************************
303 ;******************************************************************************
305 DELAY_PORT equ 0edh ; Port to use for 1uS delay
306 KBD_CONTROL_PORT equ 060h ; 8042 control port
307 KBD_STATUS_PORT equ 064h ; 8042 status port
308 WRITE_DATA_PORT_CMD equ 0d1h ; 8042 command to write the data port
309 ENABLE_A20_CMD equ 0dfh ; 8042 command to enable A20
314 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
325 ; mov byte ptr es:[160],'a'
343 sub edi,eax ; Get the address of the memory map
344 mov dword ptr [MemoryMapSize],edi ; Save the size of the memory map
347 mov bx,cs ; BX=segment
348 shl ebx,4 ; BX="linear" address of segment base
349 lea eax,[GDT_BASE + ebx] ; EAX=PHYSICAL address of gdt
350 mov dword ptr [gdtr + 2],eax ; Put address of gdt into the gdtr
351 lea eax,[IDT_BASE + ebx] ; EAX=PHYSICAL address of idt
352 mov dword ptr [idtr + 2],eax ; Put address of idt into the idtr
353 lea edx,[MemoryMapSize + ebx] ; Physical base address of the memory map
355 add ebx,01000h ; Source of EFI32
356 mov dword ptr [JUMP+2],ebx
358 mov esi,ebx ; Source of EFILDR32
362 ; mov byte ptr es:[162],'b'
370 mov ax,2401h ; Enable A20 Gate
372 jnc A20GateEnabled ; Jump if it suceeded
375 ; If INT 15 Function 2401 is not supported, then attempt to Enable A20 manually.
378 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
379 jnz Timeout8042 ; Jump if the 8042 timed out
380 out DELAY_PORT,ax ; Delay 1 uS
381 mov al,WRITE_DATA_PORT_CMD ; 8042 cmd to write output port
382 out KBD_STATUS_PORT,al ; Send command to the 8042
383 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
384 jnz Timeout8042 ; Jump if the 8042 timed out
385 mov al,ENABLE_A20_CMD ; gate address bit 20 on
386 out KBD_CONTROL_PORT,al ; Send command to thre 8042
387 call Empty8042InputBuffer ; Empty the Input Buffer on the 8042 controller
388 mov cx,25 ; Delay 25 uS for the command to complete on the 8042
390 out DELAY_PORT,ax ; Delay 1 uS
396 mov bx,0008h ; Flat data descriptor
398 ; DISABLE INTERRUPTS - Entering Protected Mode
405 ; mov byte ptr es:[164],'c'
410 lgdt fword ptr [gdtr]
412 lidt fword ptr [idtr]
418 ; jmp far 0010:00020000
424 Empty8042InputBuffer:
427 out DELAY_PORT,ax ; Delay 1us
428 in al,KBD_STATUS_PORT ; Read the 8042 Status Port
429 and al,02h ; Check the Input Buffer Full Flag
430 loopnz Empty8042Loop ; Loop until the input buffer is empty or a timout of 65536 uS
433 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
435 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
439 gdtr dw GDT_END - GDT_BASE - 1 ; GDT limit
440 dd 0 ; (GDT base gets set above)
441 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
442 ; global descriptor table (GDT)
443 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
450 NULL_SEL equ $-GDT_BASE
455 db 0 ; limit 19:16, flags
458 ; linear data segment descriptor
459 LINEAR_SEL equ $-GDT_BASE
460 dw 0FFFFh ; limit 0xFFFFF
463 db 092h ; present, ring 0, data, expand-up, writable
464 db 0CFh ; page-granular, 32-bit
467 ; linear code segment descriptor
468 LINEAR_CODE_SEL equ $-GDT_BASE
469 dw 0FFFFh ; limit 0xFFFFF
472 db 09Ah ; present, ring 0, data, expand-up, writable
473 db 0CFh ; page-granular, 32-bit
476 ; system data segment descriptor
477 SYS_DATA_SEL equ $-GDT_BASE
478 dw 0FFFFh ; limit 0xFFFFF
481 db 092h ; present, ring 0, data, expand-up, writable
482 db 0CFh ; page-granular, 32-bit
485 ; system code segment descriptor
486 SYS_CODE_SEL equ $-GDT_BASE
487 dw 0FFFFh ; limit 0xFFFFF
490 db 09Ah ; present, ring 0, data, expand-up, writable
491 db 0CFh ; page-granular, 32-bit
494 ; spare segment descriptor
495 SPARE3_SEL equ $-GDT_BASE
499 db 0 ; present, ring 0, data, expand-up, writable
500 db 0 ; page-granular, 32-bit
503 ; spare segment descriptor
504 SPARE4_SEL equ $-GDT_BASE
508 db 0 ; present, ring 0, data, expand-up, writable
509 db 0 ; page-granular, 32-bit
512 ; spare segment descriptor
513 SPARE5_SEL equ $-GDT_BASE
517 db 0 ; present, ring 0, data, expand-up, writable
518 db 0 ; page-granular, 32-bit
527 idtr dw IDT_END - IDT_BASE - 1 ; IDT limit
528 dd 0 ; (IDT base gets set above)
529 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
530 ; interrupt descriptor table (IDT)
532 ; Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ
533 ; mappings. This implementation only uses the system timer and all other
534 ; IRQs will remain masked. The descriptors for vectors 33+ are provided
536 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
543 ; divide by zero (INT 0)
544 DIV_ZERO_SEL equ $-IDT_BASE
546 dw SYS_CODE_SEL ; selector 15:0
547 db 0 ; 0 for interrupt gate
548 db 0eh OR 80h ; type = 386 interrupt gate, present
551 ; debug exception (INT 1)
552 DEBUG_EXCEPT_SEL equ $-IDT_BASE
554 dw SYS_CODE_SEL ; selector 15:0
555 db 0 ; 0 for interrupt gate
556 db 0eh OR 80h ; type = 386 interrupt gate, present
560 NMI_SEL equ $-IDT_BASE
562 dw SYS_CODE_SEL ; selector 15:0
563 db 0 ; 0 for interrupt gate
564 db 0eh OR 80h ; type = 386 interrupt gate, present
567 ; soft breakpoint (INT 3)
568 BREAKPOINT_SEL equ $-IDT_BASE
570 dw SYS_CODE_SEL ; selector 15:0
571 db 0 ; 0 for interrupt gate
572 db 0eh OR 80h ; type = 386 interrupt gate, present
576 OVERFLOW_SEL equ $-IDT_BASE
578 dw SYS_CODE_SEL ; selector 15:0
579 db 0 ; 0 for interrupt gate
580 db 0eh OR 80h ; type = 386 interrupt gate, present
583 ; bounds check (INT 5)
584 BOUNDS_CHECK_SEL equ $-IDT_BASE
586 dw SYS_CODE_SEL ; selector 15:0
587 db 0 ; 0 for interrupt gate
588 db 0eh OR 80h ; type = 386 interrupt gate, present
591 ; invalid opcode (INT 6)
592 INVALID_OPCODE_SEL equ $-IDT_BASE
594 dw SYS_CODE_SEL ; selector 15:0
595 db 0 ; 0 for interrupt gate
596 db 0eh OR 80h ; type = 386 interrupt gate, present
599 ; device not available (INT 7)
600 DEV_NOT_AVAIL_SEL equ $-IDT_BASE
602 dw SYS_CODE_SEL ; selector 15:0
603 db 0 ; 0 for interrupt gate
604 db 0eh OR 80h ; type = 386 interrupt gate, present
607 ; double fault (INT 8)
608 DOUBLE_FAULT_SEL equ $-IDT_BASE
610 dw SYS_CODE_SEL ; selector 15:0
611 db 0 ; 0 for interrupt gate
612 db 0eh OR 80h ; type = 386 interrupt gate, present
615 ; Coprocessor segment overrun - reserved (INT 9)
616 RSVD_INTR_SEL1 equ $-IDT_BASE
618 dw SYS_CODE_SEL ; selector 15:0
619 db 0 ; 0 for interrupt gate
620 db 0eh OR 80h ; type = 386 interrupt gate, present
623 ; invalid TSS (INT 0ah)
624 INVALID_TSS_SEL equ $-IDT_BASE
626 dw SYS_CODE_SEL ; selector 15:0
627 db 0 ; 0 for interrupt gate
628 db 0eh OR 80h ; type = 386 interrupt gate, present
631 ; segment not present (INT 0bh)
632 SEG_NOT_PRESENT_SEL equ $-IDT_BASE
634 dw SYS_CODE_SEL ; selector 15:0
635 db 0 ; 0 for interrupt gate
636 db 0eh OR 80h ; type = 386 interrupt gate, present
639 ; stack fault (INT 0ch)
640 STACK_FAULT_SEL equ $-IDT_BASE
642 dw SYS_CODE_SEL ; selector 15:0
643 db 0 ; 0 for interrupt gate
644 db 0eh OR 80h ; type = 386 interrupt gate, present
647 ; general protection (INT 0dh)
648 GP_FAULT_SEL equ $-IDT_BASE
650 dw SYS_CODE_SEL ; selector 15:0
651 db 0 ; 0 for interrupt gate
652 db 0eh OR 80h ; type = 386 interrupt gate, present
655 ; page fault (INT 0eh)
656 PAGE_FAULT_SEL equ $-IDT_BASE
658 dw SYS_CODE_SEL ; selector 15:0
659 db 0 ; 0 for interrupt gate
660 db 0eh OR 80h ; type = 386 interrupt gate, present
663 ; Intel reserved - do not use (INT 0fh)
664 RSVD_INTR_SEL2 equ $-IDT_BASE
666 dw SYS_CODE_SEL ; selector 15:0
667 db 0 ; 0 for interrupt gate
668 db 0eh OR 80h ; type = 386 interrupt gate, present
671 ; floating point error (INT 10h)
672 FLT_POINT_ERR_SEL equ $-IDT_BASE
674 dw SYS_CODE_SEL ; selector 15:0
675 db 0 ; 0 for interrupt gate
676 db 0eh OR 80h ; type = 386 interrupt gate, present
679 ; alignment check (INT 11h)
680 ALIGNMENT_CHECK_SEL equ $-IDT_BASE
682 dw SYS_CODE_SEL ; selector 15:0
683 db 0 ; 0 for interrupt gate
684 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
687 ; machine check (INT 12h)
688 MACHINE_CHECK_SEL equ $-IDT_BASE
690 dw SYS_CODE_SEL ; selector 15:0
691 db 0 ; 0 for interrupt gate
692 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
695 ; SIMD floating-point exception (INT 13h)
696 SIMD_EXCEPTION_SEL equ $-IDT_BASE
698 dw SYS_CODE_SEL ; selector 15:0
699 db 0 ; 0 for interrupt gate
700 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
703 ; 85 unspecified descriptors, First 12 of them are reserved, the rest are avail
706 ; IRQ 0 (System timer) - (INT 68h)
707 IRQ0_SEL equ $-IDT_BASE
709 dw SYS_CODE_SEL ; selector 15:0
710 db 0 ; 0 for interrupt gate
711 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
714 ; IRQ 1 (8042 Keyboard controller) - (INT 69h)
715 IRQ1_SEL equ $-IDT_BASE
717 dw SYS_CODE_SEL ; selector 15:0
718 db 0 ; 0 for interrupt gate
719 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
722 ; Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah)
723 IRQ2_SEL equ $-IDT_BASE
725 dw SYS_CODE_SEL ; selector 15:0
726 db 0 ; 0 for interrupt gate
727 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
730 ; IRQ 3 (COM 2) - (INT 6bh)
731 IRQ3_SEL equ $-IDT_BASE
733 dw SYS_CODE_SEL ; selector 15:0
734 db 0 ; 0 for interrupt gate
735 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
738 ; IRQ 4 (COM 1) - (INT 6ch)
739 IRQ4_SEL equ $-IDT_BASE
741 dw SYS_CODE_SEL ; selector 15:0
742 db 0 ; 0 for interrupt gate
743 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
746 ; IRQ 5 (LPT 2) - (INT 6dh)
747 IRQ5_SEL equ $-IDT_BASE
749 dw SYS_CODE_SEL ; selector 15:0
750 db 0 ; 0 for interrupt gate
751 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
754 ; IRQ 6 (Floppy controller) - (INT 6eh)
755 IRQ6_SEL equ $-IDT_BASE
757 dw SYS_CODE_SEL ; selector 15:0
758 db 0 ; 0 for interrupt gate
759 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
762 ; IRQ 7 (LPT 1) - (INT 6fh)
763 IRQ7_SEL equ $-IDT_BASE
765 dw SYS_CODE_SEL ; selector 15:0
766 db 0 ; 0 for interrupt gate
767 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
770 ; IRQ 8 (RTC Alarm) - (INT 70h)
771 IRQ8_SEL equ $-IDT_BASE
773 dw SYS_CODE_SEL ; selector 15:0
774 db 0 ; 0 for interrupt gate
775 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
779 IRQ9_SEL equ $-IDT_BASE
781 dw SYS_CODE_SEL ; selector 15:0
782 db 0 ; 0 for interrupt gate
783 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
787 IRQ10_SEL equ $-IDT_BASE
789 dw SYS_CODE_SEL ; selector 15:0
790 db 0 ; 0 for interrupt gate
791 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
795 IRQ11_SEL equ $-IDT_BASE
797 dw SYS_CODE_SEL ; selector 15:0
798 db 0 ; 0 for interrupt gate
799 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
802 ; IRQ 12 (PS/2 mouse) - (INT 74h)
803 IRQ12_SEL equ $-IDT_BASE
805 dw SYS_CODE_SEL ; selector 15:0
806 db 0 ; 0 for interrupt gate
807 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
810 ; IRQ 13 (Floating point error) - (INT 75h)
811 IRQ13_SEL equ $-IDT_BASE
813 dw SYS_CODE_SEL ; selector 15:0
814 db 0 ; 0 for interrupt gate
815 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
818 ; IRQ 14 (Secondary IDE) - (INT 76h)
819 IRQ14_SEL equ $-IDT_BASE
821 dw SYS_CODE_SEL ; selector 15:0
822 db 0 ; 0 for interrupt gate
823 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
826 ; IRQ 15 (Primary IDE) - (INT 77h)
827 IRQ15_SEL equ $-IDT_BASE
829 dw SYS_CODE_SEL ; selector 15:0
830 db 0 ; 0 for interrupt gate
831 db 0eh OR 80h ; (10001110)type = 386 interrupt gate, present
839 MemoryMap dd 0,0,0,0,0,0,0,0
870 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
871 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
875 ; below is the pieces of the IVT that is used to redirect INT 68h - 6fh
876 ; back to INT 08h - 0fh when in real mode... It is 'org'ed to a
877 ; known low address (20f00) so it can be set up by PlMapIrqToVect in