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	 697ecfd313
			
		
	
	
		697ecfd313
		
	
	
	
	
		
			
			Signed-off-by: rsun3 Reviewed-by: niruiyu git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12773 6f19259b-4bc3-4df7-8a09-765794883524
		
			
				
	
	
		
			911 lines
		
	
	
		
			35 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			911 lines
		
	
	
		
			35 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| #------------------------------------------------------------------------------
 | |
| #*
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| #*   Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
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| #*   This program and the accompanying materials                          
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| #*   are licensed and made available under the terms and conditions of the BSD License         
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| #*   which accompanies this distribution.  The full text of the license may be found at        
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| #*   http://opensource.org/licenses/bsd-license.php                                            
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| #*                                                                                             
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| #*   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
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| #*   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             
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| #*   
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| #*    start16.asm
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| #*  
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| #*   Abstract:
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| #*
 | |
| #------------------------------------------------------------------------------
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| 
 | |
|         #.MODEL small
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|         .stack: 
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|         .486p: 
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|         .code16 
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| 
 | |
| .equ                        FAT_DIRECTORY_ENTRY_SIZE,   0x0020
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| .equ                        FAT_DIRECTORY_ENTRY_SHIFT,  5
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| .equ                        BLOCK_SIZE,                 0x0200
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| .equ                        BLOCK_MASK,                 0x01ff
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| .equ                        BLOCK_SHIFT,                9
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| 
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|         .org 0x00
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| 
 | |
| .global _start
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| _start:
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| 
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| Ia32Jump: 
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|   jmp   BootSectorEntryPoint  # JMP inst    - 3 bytes
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|   nop
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| 
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| OemId:             .ascii  "INTEL   "    # OemId               - 8 bytes
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| 
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| SectorSize:        .word  0              # Sector Size         - 16 bits
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| SectorsPerCluster: .byte  0              # Sector Per Cluster  - 8 bits
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| ReservedSectors:   .word  0              # Reserved Sectors    - 16 bits
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| NoFats:            .byte  0              # Number of FATs      - 8 bits
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| RootEntries:       .word  0              # Root Entries        - 16 bits
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| Sectors:           .word  0              # Number of Sectors   - 16 bits
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| Media:             .byte  0              # Media               - 8 bits  - ignored
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| SectorsPerFat:     .word  0              # Sectors Per FAT     - 16 bits
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| SectorsPerTrack:   .word  0              # Sectors Per Track   - 16 bits - ignored
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| Heads:             .word  0              # Heads               - 16 bits - ignored
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| HiddenSectors:     .long  0              # Hidden Sectors      - 32 bits - ignored
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| LargeSectors:      .long  0              # Large Sectors       - 32 bits 
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| PhysicalDrive:     .byte  0              # PhysicalDriveNumber - 8 bits  - ignored
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| CurrentHead:       .byte  0              # Current Head        - 8 bits
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| Signature:         .byte  0              # Signature           - 8 bits  - ignored
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| VolId:             .ascii  "    "        # Volume Serial Number- 4 bytes
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| FatLabel:          .ascii  "           " # Label               - 11 bytes
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| SystemId:          .ascii  "FAT16   "    # SystemId            - 8 bytes
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| 
 | |
| BootSectorEntryPoint: 
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|         #ASSUME ds:@code
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|         #ASSUME ss:@code
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|       # ds = 1000, es = 2000 + x (size of first cluster >> 4)
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|       # cx = Start Cluster of EfiLdr
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|       # dx = Start Cluster of Efivar.bin
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| 
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| # Re use the BPB data stored in Boot Sector
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|         movw    $0x7c00, %bp
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| 
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|         pushw   %cx
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| # Read Efivar.bin
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| #       1000:dx    = DirectoryEntry of Efivar.bin -> BS.com has filled already
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|         movw    $0x1900, %ax
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|         movw    %ax, %es
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|         testw   %dx, %dx
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|         jnz     CheckVarStoreSize
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| 
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|         movb    $1, %al
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| NoVarStore: 
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|         pushw   %es
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| # Set the 5th byte start @ 0:19000 to non-zero indicating we should init var store header in DxeIpl
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|         movb    %al, %es:4
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|         jmp     SaveVolumeId
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| 
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| CheckVarStoreSize: 
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|         movw    %dx, %di
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|         cmpl    $0x4000, %ds:2(%di)
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|         movb    $2, %al
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|         jne     NoVarStore
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| 
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| LoadVarStore: 
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|         movb    $0, %al
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|         movb    %al, %es:4
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|         movw    (%di), %cx
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| #       ES:DI = 1500:0
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|         xorw    %di, %di
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|         pushw   %es
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|         movw    $0x1500, %ax
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|         movw    %ax, %es
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|         call    ReadFile
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| SaveVolumeId: 
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|         popw    %es
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|         movw    VolId(%bp), %ax
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|         movw    %ax, %es:0                      # Save Volume Id to 0:19000. we will find the correct volume according to this VolumeId
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|         movw    VolId+2(%bp), %ax
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|         movw    %ax, %es:2
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| 
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| # Read Efildr
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|         popw    %cx
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| #       cx    = Start Cluster of Efildr -> BS.com has filled already
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| #       ES:DI = 2000:0, first cluster will be read again
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|         xorw    %di, %di                            # di = 0
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|         movw    $0x2000, %ax
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|         movw    %ax, %es
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|         call    ReadFile
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|         movw    %cs, %ax
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|         movw    %ax, %cs:JumpSegment
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| 
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| JumpFarInstruction: 
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|         .byte   0xea
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| JumpOffset: 
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|         .word   0x200
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| JumpSegment: 
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|         .word   0x2000
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| 
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| 
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| 
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| # ****************************************************************************
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| # ReadFile
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| #
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| # Arguments:
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| #   CX    = Start Cluster of File
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| #   ES:DI = Buffer to store file content read from disk
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| #
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| # Return:
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| #   (ES << 4 + DI) = end of file content Buffer
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| #
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| # ****************************************************************************
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| ReadFile: 
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| # si      = NumberOfClusters
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| # cx      = ClusterNumber
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| # dx      = CachedFatSectorNumber
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| # ds:0000 = CacheFatSectorBuffer
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| # es:di   = Buffer to load file
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| # bx      = NextClusterNumber
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|         pusha
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|         movw    $1, %si                             # NumberOfClusters = 1
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|         pushw   %cx                                 # Push Start Cluster onto stack
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|         movw    $0xfff, %dx                         # CachedFatSectorNumber = 0xfff
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| FatChainLoop: 
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|         movw    %cx, %ax                            # ax = ClusterNumber    
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|         andw    $0xfff8, %ax                        # ax = ax & 0xfff8
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|         cmpw    $0xfff8, %ax                        # See if this is the last cluster
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|         je      FoundLastCluster                    # Jump if last cluster found
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|         movw    %cx, %ax                            # ax = ClusterNumber
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|         shlw    %ax                                 # FatOffset = ClusterNumber * 2
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|         pushw   %si                                 # Save si
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|         movw    %ax, %si                            # si = FatOffset
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|         shrw    $BLOCK_SHIFT, %ax                   # ax = FatOffset >> BLOCK_SHIFT
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|         addw    ReservedSectors(%bp), %ax           # ax = FatSectorNumber = ReservedSectors + (FatOffset >> BLOCK_OFFSET)
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|         andw    $BLOCK_MASK, %si                    # si = FatOffset & BLOCK_MASK
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|         cmpw    %dx, %ax                            # Compare FatSectorNumber to CachedFatSectorNumber
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|         je      SkipFatRead
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|         movw    $2, %bx
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|         pushw   %es
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|         pushw   %ds
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|         popw    %es
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|         call    ReadBlocks                          # Read 2 blocks starting at AX storing at ES:DI
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|         popw    %es
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|         movw    %ax, %dx                            # CachedFatSectorNumber = FatSectorNumber
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| SkipFatRead: 
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|         movw    (%si), %bx                          # bx = NextClusterNumber
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|         movw    %cx, %ax                            # ax = ClusterNumber
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|         popw    %si                                 # Restore si
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|         decw    %bx                                 # bx = NextClusterNumber - 1
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|         cmpw    %cx, %bx                            # See if (NextClusterNumber-1)==ClusterNumber
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|         jne     ReadClusters
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|         incw    %bx                                 # bx = NextClusterNumber
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|         incw    %si                                 # NumberOfClusters++
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|         movw    %bx, %cx                            # ClusterNumber = NextClusterNumber
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|         jmp     FatChainLoop
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| ReadClusters: 
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|         incw    %bx
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|         popw    %ax                                 # ax = StartCluster
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|         pushw   %bx                                 # StartCluster = NextClusterNumber
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|         movw    %bx, %cx                            # ClusterNumber = NextClusterNumber
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|         subw    $2, %ax                             # ax = StartCluster - 2
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|         xorb    %bh, %bh
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|         movb    SectorsPerCluster(%bp), %bl         # bx = SectorsPerCluster
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|         mulw    %bx                                 # ax = (StartCluster - 2) * SectorsPerCluster
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|         addw    (%bp), %ax                          # ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster
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|         pushw   %ax                                 # save start sector
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|         movw    %si, %ax                            # ax = NumberOfClusters
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|         mulw    %bx                                 # ax = NumberOfClusters * SectorsPerCluster
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|         movw    %ax, %bx                            # bx = Number of Sectors
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|         popw    %ax                                 # ax = Start Sector
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|         call    ReadBlocks
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|         movw    $1, %si                             # NumberOfClusters = 1
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|         jmp     FatChainLoop
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| FoundLastCluster: 
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|         popw    %cx
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|         popa
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|         ret
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| 
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| 
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| # ****************************************************************************
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| # ReadBlocks - Reads a set of blocks from a block device
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| #
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| # AX    = Start LBA
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| # BX    = Number of Blocks to Read
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| # ES:DI = Buffer to store sectors read from disk
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| # ****************************************************************************
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| 
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| # cx = Blocks
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| # bx = NumberOfBlocks
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| # si = StartLBA
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| 
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| ReadBlocks: 
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|         pusha
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|         addl    LBAOffsetForBootSector(%bp), %eax            # Add LBAOffsetForBootSector to Start LBA
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|         addl    HiddenSectors(%bp), %eax            # Add HiddenSectors to Start LBA
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|         movl    %eax, %esi                          # esi = Start LBA
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|         movw    %bx, %cx                            # cx = Number of blocks to read
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| ReadCylinderLoop: 
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|         movw    $0x7bfc, %bp                        # bp = 0x7bfc
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|         movl    %esi, %eax                          # eax = Start LBA
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|         xorl    %edx, %edx                          # edx = 0
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|         movzwl  (%bp), %ebx                         # bx = MaxSector
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|         divl    %ebx                                # ax = StartLBA / MaxSector
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|         incw    %dx                                 # dx = (StartLBA % MaxSector) + 1
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| 
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|         movw    (%bp), %bx                          # bx = MaxSector
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|         subw    %dx, %bx                            # bx = MaxSector - Sector
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|         incw    %bx                                 # bx = MaxSector - Sector + 1
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|         cmpw    %bx, %cx                            # Compare (Blocks) to (MaxSector - Sector + 1)
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|         jg      LimitTransfer
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|         movw    %cx, %bx                            # bx = Blocks
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| LimitTransfer: 
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|         pushw   %ax                                 # save ax
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|         movw    %es, %ax                            # ax = es
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|         shrw    $(BLOCK_SHIFT-4), %ax               # ax = Number of blocks into mem system
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|         andw    $0x7f, %ax                          # ax = Number of blocks into current seg
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|         addw    %bx, %ax                            # ax = End Block number of transfer
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|         cmpw    $0x80, %ax                          # See if it crosses a 64K boundry
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|         jle     NotCrossing64KBoundry               # Branch if not crossing 64K boundry
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|         subw    $0x80, %ax                          # ax = Number of blocks past 64K boundry
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|         subw    %ax, %bx                            # Decrease transfer size by block overage
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| NotCrossing64KBoundry: 
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|         popw    %ax                                 # restore ax
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| 
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|         pushw   %cx
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|         movb    %dl, %cl                            # cl = (StartLBA % MaxSector) + 1 = Sector
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|         xorw    %dx, %dx                            # dx = 0
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|         divw    2(%bp)                              # ax = ax / (MaxHead + 1) = Cylinder  
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|                                                     # dx = ax % (MaxHead + 1) = Head
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| 
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|         pushw   %bx                                 # Save number of blocks to transfer
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|         movb    %dl, %dh                            # dh = Head
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|         movw    $0x7c00, %bp                        # bp = 0x7c00
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|         movb    PhysicalDrive(%bp), %dl             # dl = Drive Number
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|         movb    %al, %ch                            # ch = Cylinder
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|         movb    %bl, %al                            # al = Blocks
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|         movb    $2, %ah                             # ah = Function 2
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|         movw    %di, %bx                            # es:bx = Buffer address
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|         int     $0x13
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|         jc      DiskError
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|         popw    %bx
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|         popw    %cx
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|         movzwl  %bx, %ebx
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|         addl    %ebx, %esi                          # StartLBA = StartLBA + NumberOfBlocks
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|         subw    %bx, %cx                            # Blocks = Blocks - NumberOfBlocks
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|         movw    %es, %ax
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|         shlw    $(BLOCK_SHIFT-4), %bx
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|         addw    %bx, %ax
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|         movw    %ax, %es                            # es:di = es:di + NumberOfBlocks*BLOCK_SIZE
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|         cmpw    $0, %cx
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|         jne     ReadCylinderLoop
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|         popa
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|         ret
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| 
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| DiskError: 
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|         pushw %cs
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|         popw %ds
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|         leaw ErrorString, %si
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|         movw $7, %cx
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|         jmp  PrintStringAndHalt
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| 
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| PrintStringAndHalt: 
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|         movw $0xb800, %ax
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|         movw %ax, %es
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|         movw $160, %di
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|         rep
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|         movsw
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| Halt: 
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|         jmp   Halt
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| 
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| ErrorString: 
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|         .byte 'S', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, 'o', 0x0c, 'r', 0x0c, '!', 0x0c
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| 
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|         # .org     0x01fa # Just for passing build.
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| LBAOffsetForBootSector: 
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|         .long   0x0
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| 
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|         # .org     0x01fe # Just for passing build.
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|         .word   0xaa55
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| 
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| #******************************************************************************
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| #******************************************************************************
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| #******************************************************************************
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| 
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| .equ                 DELAY_PORT,            0x0ed     # Port to use for 1uS delay
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| .equ                 KBD_CONTROL_PORT,      0x060     # 8042 control port     
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| .equ                 KBD_STATUS_PORT,       0x064     # 8042 status port      
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| .equ                 WRITE_DATA_PORT_CMD,   0x0d1     # 8042 command to write the data port
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| .equ                 ENABLE_A20_CMD,        0x0df     # 8042 command to enable A20
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| 
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|         # .org     0x0200 # Just for passing build.
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|         jmp start
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| Em64String: 
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|         .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
 | |
| 
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| start:  
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|         movw %cs, %ax
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|         movw %ax, %ds
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|         movw %ax, %es
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|         movw %ax, %ss
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|         movw $MyStack, %sp
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| 
 | |
| #        mov ax,0b800h
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| #        mov es,ax
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| #        mov byte ptr es:[160],'a'
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| #        mov ax,cs
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| #        mov es,ax
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| 
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|         movl $0, %ebx
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|         leal MemoryMap, %edi
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| MemMapLoop: 
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|         movl $0xe820, %eax
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|         movl $20, %ecx
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|         movl $0x534d4150, %edx  # 0x534d4150  stands for 'SMAP'
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|         int $0x15
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|         jc  MemMapDone
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|         addl $20, %edi
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|         cmpl $0, %ebx
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|         je  MemMapDone
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|         jmp MemMapLoop
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| MemMapDone: 
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|         leal MemoryMap, %eax
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|         subl %eax, %edi                     # Get the address of the memory map
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|         movl %edi, MemoryMapSize            # Save the size of the memory map
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| 
 | |
|         xorl    %ebx, %ebx
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|         movw    %cs, %bx                    # BX=segment
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|         shll    $4, %ebx                    # BX="linear" address of segment base
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|         leal    GDT_BASE(%ebx), %eax        # EAX=PHYSICAL address of gdt
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|         movl    %eax, gdtr + 2              # Put address of gdt into the gdtr
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|         leal    IDT_BASE(%ebx), %eax        # EAX=PHYSICAL address of idt
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|         movl    %eax, idtr + 2              # Put address of idt into the idtr
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|         leal    MemoryMapSize(%ebx), %edx   # Physical base address of the memory map
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| 
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|         addl $0x1000, %ebx                  # Source of EFI32
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|         movl %ebx, JUMP+2
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|         addl $0x1000, %ebx
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|         movl %ebx, %esi                     # Source of EFILDR32
 | |
| 
 | |
| #        mov ax,0b800h
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| #        mov es,ax
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| #        mov byte ptr es:[162],'b'
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| #        mov ax,cs
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| #        mov es,ax
 | |
| 
 | |
| #
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| # Enable A20 Gate 
 | |
| #
 | |
| 
 | |
|         movw $0x2401, %ax                   # Enable A20 Gate
 | |
|         int $0x15
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|         jnc A20GateEnabled                  # Jump if it suceeded
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| 
 | |
| #
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| # If INT 15 Function 2401 is not supported, then attempt to Enable A20 manually.
 | |
| #
 | |
| 
 | |
|         call    Empty8042InputBuffer        # Empty the Input Buffer on the 8042 controller
 | |
|         jnz     Timeout8042                 # Jump if the 8042 timed out
 | |
|         outw    %ax, $DELAY_PORT            # Delay 1 uS
 | |
|         movb    $WRITE_DATA_PORT_CMD, %al   # 8042 cmd to write output port
 | |
|         outb    %al, $KBD_STATUS_PORT       # Send command to the 8042
 | |
|         call    Empty8042InputBuffer        # Empty the Input Buffer on the 8042 controller
 | |
|         jnz     Timeout8042                 # Jump if the 8042 timed out
 | |
|         movb    $ENABLE_A20_CMD, %al        # gate address bit 20 on
 | |
|         outb    %al, $KBD_CONTROL_PORT      # Send command to thre 8042
 | |
|         call    Empty8042InputBuffer        # Empty the Input Buffer on the 8042 controller
 | |
|         movw    $25, %cx                    # Delay 25 uS for the command to complete on the 8042
 | |
| Delay25uS: 
 | |
|         outw    %ax, $DELAY_PORT            # Delay 1 uS
 | |
|         loop    Delay25uS
 | |
| Timeout8042: 
 | |
| 
 | |
| 
 | |
| A20GateEnabled: 
 | |
|         movw    $0x0008, %bx                # Flat data descriptor
 | |
| #
 | |
| # DISABLE INTERRUPTS - Entering Protected Mode
 | |
| #
 | |
| 
 | |
|         cli
 | |
| 
 | |
| #        mov ax,0b800h
 | |
| #        mov es,ax
 | |
| #        mov byte ptr es:[164],'c'
 | |
| #        mov ax,cs
 | |
| #        mov es,ax
 | |
| 
 | |
|         .byte   0x66
 | |
|         lgdt    gdtr
 | |
|         .byte   0x66
 | |
|         lidt    idtr
 | |
| 
 | |
|         movl    %cr0, %eax
 | |
|         orb     $1, %al
 | |
|         movl    %eax, %cr0
 | |
| JUMP: 
 | |
| # jmp far 0010:00020000
 | |
|         .byte 0x66
 | |
|         .byte 0xea
 | |
|         .long 0x00020000
 | |
|         .word 0x0010
 | |
| 
 | |
| Empty8042InputBuffer: 
 | |
|         movw $0, %cx
 | |
| Empty8042Loop: 
 | |
|         outw    %ax, $DELAY_PORT            # Delay 1us
 | |
|         inb     $KBD_STATUS_PORT, %al       # Read the 8042 Status Port
 | |
|         andb    $0x2, %al                   # Check the Input Buffer Full Flag
 | |
|         loopnz  Empty8042Loop               # Loop until the input buffer is empty or a timout of 65536 uS
 | |
|         ret
 | |
| 
 | |
| ##############################################################################
 | |
| # data
 | |
| ##############################################################################
 | |
| 
 | |
|         .p2align 1
 | |
| 
 | |
| gdtr:   .word  GDT_END - GDT_BASE - 1       # GDT limit
 | |
|         .long 0                             # (GDT base gets set above)
 | |
| ##############################################################################
 | |
| #   global descriptor table (GDT)
 | |
| ##############################################################################
 | |
| 
 | |
|         .p2align 1
 | |
| 
 | |
| GDT_BASE: 
 | |
| # null descriptor
 | |
| .equ                NULL_SEL, .-GDT_BASE
 | |
|         .word 0         # limit 15:0
 | |
|         .word 0         # base 15:0
 | |
|         .byte 0         # base 23:16
 | |
|         .byte 0         # type
 | |
|         .byte 0         # limit 19:16, flags
 | |
|         .byte 0         # base 31:24
 | |
| 
 | |
| # linear data segment descriptor
 | |
| .equ            LINEAR_SEL, .-GDT_BASE
 | |
|         .word 0xFFFF    # limit 0xFFFFF
 | |
|         .word 0         # base 0
 | |
|         .byte 0
 | |
|         .byte 0x92      # present, ring 0, data, expand-up, writable
 | |
|         .byte 0xCF              # page-granular, 32-bit
 | |
|         .byte 0
 | |
| 
 | |
| # linear code segment descriptor
 | |
| .equ            LINEAR_CODE_SEL, .-GDT_BASE
 | |
|         .word 0xFFFF    # limit 0xFFFFF
 | |
|         .word 0         # base 0
 | |
|         .byte 0
 | |
|         .byte 0x9A      # present, ring 0, data, expand-up, writable
 | |
|         .byte 0xCF              # page-granular, 32-bit
 | |
|         .byte 0
 | |
| 
 | |
| # system data segment descriptor
 | |
| .equ            SYS_DATA_SEL, .-GDT_BASE
 | |
|         .word 0xFFFF    # limit 0xFFFFF
 | |
|         .word 0         # base 0
 | |
|         .byte 0
 | |
|         .byte 0x92      # present, ring 0, data, expand-up, writable
 | |
|         .byte 0xCF              # page-granular, 32-bit
 | |
|         .byte 0
 | |
| 
 | |
| # system code segment descriptor
 | |
| .equ            SYS_CODE_SEL, .-GDT_BASE
 | |
|         .word 0xFFFF    # limit 0xFFFFF
 | |
|         .word 0         # base 0
 | |
|         .byte 0
 | |
|         .byte 0x9A      # present, ring 0, data, expand-up, writable
 | |
|         .byte 0xCF              # page-granular, 32-bit
 | |
|         .byte 0
 | |
| 
 | |
| # spare segment descriptor
 | |
| .equ        SPARE3_SEL, .-GDT_BASE
 | |
|         .word 0         # limit 0xFFFFF
 | |
|         .word 0         # base 0
 | |
|         .byte 0
 | |
|         .byte 0         # present, ring 0, data, expand-up, writable
 | |
|         .byte 0         # page-granular, 32-bit
 | |
|         .byte 0
 | |
| 
 | |
| # spare segment descriptor
 | |
| .equ        SPARE4_SEL, .-GDT_BASE
 | |
|         .word 0         # limit 0xFFFFF
 | |
|         .word 0         # base 0
 | |
|         .byte 0
 | |
|         .byte 0         # present, ring 0, data, expand-up, writable
 | |
|         .byte 0         # page-granular, 32-bit
 | |
|         .byte 0
 | |
| 
 | |
| # spare segment descriptor
 | |
| .equ        SPARE5_SEL, .-GDT_BASE
 | |
|         .word 0         # limit 0xFFFFF
 | |
|         .word 0         # base 0
 | |
|         .byte 0
 | |
|         .byte 0         # present, ring 0, data, expand-up, writable
 | |
|         .byte 0         # page-granular, 32-bit
 | |
|         .byte 0
 | |
| 
 | |
| GDT_END: 
 | |
| 
 | |
|         .p2align 1
 | |
| 
 | |
| 
 | |
| 
 | |
| idtr:   .word IDT_END - IDT_BASE - 1  # IDT limit
 | |
|         .long 0                       # (IDT base gets set above)
 | |
| ##############################################################################
 | |
| #   interrupt descriptor table (IDT)
 | |
| #
 | |
| #   Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ
 | |
| #       mappings.  This implementation only uses the system timer and all other
 | |
| #       IRQs will remain masked.  The descriptors for vectors 33+ are provided
 | |
| #       for convenience.
 | |
| ##############################################################################
 | |
| 
 | |
| #idt_tag db "IDT",0     
 | |
|         .p2align 1
 | |
| 
 | |
| IDT_BASE: 
 | |
| # divide by zero (INT 0)
 | |
| .equ                DIV_ZERO_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # debug exception (INT 1)
 | |
| .equ                DEBUG_EXCEPT_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # NMI (INT 2)
 | |
| .equ                NMI_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # soft breakpoint (INT 3)
 | |
| .equ                BREAKPOINT_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # overflow (INT 4)
 | |
| .equ                OVERFLOW_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # bounds check (INT 5)
 | |
| .equ                BOUNDS_CHECK_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # invalid opcode (INT 6)
 | |
| .equ                INVALID_OPCODE_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # device not available (INT 7)
 | |
| .equ                DEV_NOT_AVAIL_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # double fault (INT 8)
 | |
| .equ                DOUBLE_FAULT_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # Coprocessor segment overrun - reserved (INT 9)
 | |
| .equ                RSVD_INTR_SEL1, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # invalid TSS (INT 0ah)
 | |
| .equ                INVALID_TSS_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # segment not present (INT 0bh)
 | |
| .equ                SEG_NOT_PRESENT_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # stack fault (INT 0ch)
 | |
| .equ                STACK_FAULT_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # general protection (INT 0dh)
 | |
| .equ                GP_FAULT_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # page fault (INT 0eh)
 | |
| .equ                PAGE_FAULT_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # Intel reserved - do not use (INT 0fh)
 | |
| .equ                RSVD_INTR_SEL2, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # floating point error (INT 10h)
 | |
| .equ                FLT_POINT_ERR_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # alignment check (INT 11h)
 | |
| .equ                ALIGNMENT_CHECK_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # machine check (INT 12h)
 | |
| .equ                MACHINE_CHECK_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # SIMD floating-point exception (INT 13h)
 | |
| .equ                SIMD_EXCEPTION_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # 85 unspecified descriptors, First 12 of them are reserved, the rest are avail
 | |
|         .fill  85 * 8, 1, 0
 | |
| 
 | |
| # IRQ 0 (System timer) - (INT 68h)
 | |
| .equ                IRQ0_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 1 (8042 Keyboard controller) - (INT 69h)
 | |
| .equ                IRQ1_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah)
 | |
| .equ                IRQ2_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 3 (COM 2) - (INT 6bh)
 | |
| .equ                IRQ3_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 4 (COM 1) - (INT 6ch)
 | |
| .equ                IRQ4_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 5 (LPT 2) - (INT 6dh)
 | |
| .equ                IRQ5_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 6 (Floppy controller) - (INT 6eh)
 | |
| .equ                IRQ6_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 7 (LPT 1) - (INT 6fh)
 | |
| .equ                IRQ7_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 8 (RTC Alarm) - (INT 70h)
 | |
| .equ                IRQ8_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 9 - (INT 71h)
 | |
| .equ                IRQ9_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 10 - (INT 72h)
 | |
| .equ                 IRQ10_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 11 - (INT 73h)
 | |
| .equ                 IRQ11_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 12 (PS/2 mouse) - (INT 74h)
 | |
| .equ                 IRQ12_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 13 (Floating point error) - (INT 75h)
 | |
| .equ                 IRQ13_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 14 (Secondary IDE) - (INT 76h)
 | |
| .equ                 IRQ14_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| # IRQ 15 (Primary IDE) - (INT 77h)
 | |
| .equ                 IRQ15_SEL, .-IDT_BASE
 | |
|         .word 0             # offset 15:0
 | |
|         .word SYS_CODE_SEL  # selector 15:0
 | |
|         .byte 0             # 0 for interrupt gate
 | |
|         .byte 0x0e | 0x80  # (10001110)type = 386 interrupt gate, present
 | |
|         .word 0             # offset 31:16
 | |
| 
 | |
| IDT_END: 
 | |
| 
 | |
|         .p2align 1
 | |
| 
 | |
| MemoryMapSize:  .long 0
 | |
| MemoryMap:  .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
|         .long 0,0,0,0,0,0,0,0
 | |
| 
 | |
|         .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
 | |
|         .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
 | |
| 
 | |
|         .org 0x0fe0
 | |
| MyStack:    
 | |
|         # below is the pieces of the IVT that is used to redirect INT 68h - 6fh
 | |
|         #    back to INT 08h - 0fh  when in real mode...  It is 'org'ed to a
 | |
|         #    known low address (20f00) so it can be set up by PlMapIrqToVect in
 | |
|         #    8259.c
 | |
| 
 | |
|         int $8
 | |
|         iret
 | |
| 
 | |
|         int $9
 | |
|         iret
 | |
| 
 | |
|         int $10
 | |
|         iret
 | |
| 
 | |
|         int $11
 | |
|         iret
 | |
| 
 | |
|         int $12
 | |
|         iret
 | |
| 
 | |
|         int $13
 | |
|         iret
 | |
| 
 | |
|         int $14
 | |
|         iret
 | |
| 
 | |
|         int $15
 | |
|         iret
 | |
| 
 | |
| 
 | |
|         .org 0x0ffe
 | |
| BlockSignature: 
 | |
|         .word 0xaa55
 |