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Diffstat (limited to 'DuetPkg/BootSector/bs32.S')
| -rw-r--r-- | DuetPkg/BootSector/bs32.S | 312 |
1 files changed, 0 insertions, 312 deletions
diff --git a/DuetPkg/BootSector/bs32.S b/DuetPkg/BootSector/bs32.S deleted file mode 100644 index 2584517386..0000000000 --- a/DuetPkg/BootSector/bs32.S +++ /dev/null @@ -1,312 +0,0 @@ -#------------------------------------------------------------------------------
-#*
-#* Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>
-#* This program and the accompanying materials
-#* are licensed and made available under the terms and conditions of the BSD License
-#* which accompanies this distribution. The full text of the license may be found at
-#* http://opensource.org/licenses/bsd-license.php
-#*
-#* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
-#* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
-#*
-#* bs32.asm
-#*
-#* Abstract:
-#*
-#------------------------------------------------------------------------------
-
- #.MODEL small
- .stack:
- .486p:
- .code16
-
-.equ FAT_DIRECTORY_ENTRY_SIZE, 0x0020
-.equ FAT_DIRECTORY_ENTRY_SHIFT, 5
-.equ BLOCK_SIZE, 0x0200
-.equ BLOCK_MASK, 0x01ff
-.equ BLOCK_SHIFT, 9
- # "EFILDR_____"
-.equ LOADER_FILENAME_PART1, 0x4c494645 # "EFIL"
-.equ LOADER_FILENAME_PART2, 0x30325244 # "DR20"
-.equ LOADER_FILENAME_PART3, 0x20202030 # "0___"
-
- .org 0x0
-.global _start
-_start:
-Ia32Jump:
- jmp BootSectorEntryPoint # JMP inst - 3 bytes
- nop
-
-OemId: .ascii "INTEL " # OemId - 8 bytes
-# BPB data below will be fixed by tool
-SectorSize: .word 0 # Sector Size - 16 bits
-SectorsPerCluster: .byte 0 # Sector Per Cluster - 8 bits
-ReservedSectors: .word 0 # Reserved Sectors - 16 bits
-NoFats: .byte 0 # Number of FATs - 8 bits
-RootEntries: .word 0 # Root Entries - 16 bits
-Sectors: .word 0 # Number of Sectors - 16 bits
-Media: .byte 0 # Media - 8 bits - ignored
-SectorsPerFat: .word 0 # Sectors Per FAT - 16 bits
-SectorsPerTrack: .word 0 # Sectors Per Track - 16 bits - ignored
-Heads: .word 0 # Heads - 16 bits - ignored
-HiddenSectors: .long 0 # Hidden Sectors - 32 bits - ignored
-LargeSectors: .long 0 # Large Sectors - 32 bits
-
-#******************************************************************************
-#
-#The structure for FAT32 starting at offset 36 of the boot sector. (At this point,
-#the BPB/boot sector for FAT12 and FAT16 differs from the BPB/boot sector for FAT32.)
-#
-#******************************************************************************
-
-SectorsPerFat32: .long 0 # Sectors Per FAT for FAT32 - 4 bytes
-ExtFlags: .word 0 # Mirror Flag - 2 bytes
-FSVersion: .word 0 # File System Version - 2 bytes
-RootCluster: .long 0 # 1st Cluster Number of Root Dir - 4 bytes
-FSInfo: .word 0 # Sector Number of FSINFO - 2 bytes
-BkBootSector: .word 0 # Sector Number of Bk BootSector - 2 bytes
-Reserved: .fill 12, 1, 0 # Reserved Field - 12 bytes
-PhysicalDrive: .byte 0 # Physical Drive Number - 1 byte
-Reserved1: .byte 0 # Reserved Field - 1 byte
-Signature: .byte 0 # Extended Boot Signature - 1 byte
-VolId: .ascii " " # Volume Serial Number - 4 bytes
-FatLabel: .ascii " " # Volume Label - 11 bytes
-FileSystemType: .ascii "FAT32 " # File System Type - 8 bytes
-BootSectorEntryPoint:
- #ASSUME ds:@code
- #ASSUME ss:@code
-
-# ****************************************************************************
-# Start Print
-# ****************************************************************************
- movw $StartString, %si
- call PrintString
-
-# ****************************************************************************
-# Print over
-# ****************************************************************************
-
- movw %cs, %ax # ax = 0
- movw %ax, %ss # ss = 0
- addw $0x1000, %ax
- movw %ax, %ds
-
- movw $0x7c00, %sp # sp = 0x7c00
- movw %sp, %bp # bp = 0x7c00
-
- movb $8, %ah # ah = 8 - Get Drive Parameters Function
- movb %dl, PhysicalDrive(%bp) # BBS defines that BIOS would pass the booting driver number to the loader through DL
- int $0x13 # Get Drive Parameters
- xorw %ax, %ax # ax = 0
- movb %dh, %al # al = dh
- incb %al # MaxHead = al + 1
- pushw %ax # 0000:7bfe = MaxHead
- movb %cl, %al # al = cl
- andb $0x3f, %al # MaxSector = al & 0x3f
- pushw %ax # 0000:7bfc = MaxSector
-
- cmpw $0xaa55, SectorSignature(%bp) # Verify Boot Sector Signature
- jne BadBootSector
- movw RootEntries(%bp), %cx # cx = RootEntries
- shlw $FAT_DIRECTORY_ENTRY_SHIFT, %cx # cx = cx * 32 = cx * sizeof(FAT_DIRECTORY_ENTRY) = Size of Root Directory in bytes
- movw %cx, %bx # bx = size of the Root Directory in bytes
- andw $BLOCK_MASK, %bx # See if it is an even number of sectors long
- jne BadBootSector # If is isn't, then the boot sector is bad.
- movw %cx, %bx # bx = size of the Root Directory in bytes
- shrw $BLOCK_SHIFT, %bx # bx = size of Root Directory in sectors
- movb NoFats(%bp), %al # al = NoFats
- xorb %ah, %ah # ah = 0 ==> ax = NoFats
- mulw SectorsPerFat32(%bp) # ax = NoFats * SectorsPerFat
- addw ReservedSectors(%bp), %ax # ax = NoFats * SectorsPerFat + ReservedSectors = RootLBA
- addw %bx, %ax # ax = NoFats * SectorsPerFat + ReservedSectors + RootDirSectors = FirstClusterLBA
- movw %ax, (%bp) # Save FirstClusterLBA for later use
-
- movw RootCluster(%bp), %ax # ax = StartCluster of Root Directory
- subw $2, %ax # ax = StartCluster - 2
- xorb %bh, %bh
- movb SectorsPerCluster(%bp), %bl # bx = SectorsPerCluster
- mulw %bx # ax = (StartCluster - 2) * SectorsPerCluster
- addw (%bp), %ax # ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster
- pushw %ds
- popw %es
- xorw %di, %di # Store directory in es:di = 1000:0000
- call ReadBlocks # Read StartCluster of Root Directory
-
- # dx - variable storage (initial value is 0)
- # bx - loader (initial value is 0)
- xorw %dx, %dx
- xorw %bx, %bx
-
-FindEFILDR:
- cmpl $LOADER_FILENAME_PART1, (%di)
- jne FindVARSTORE
- cmpl $LOADER_FILENAME_PART2, 4(%di)
- jne FindVARSTORE
- cmpl $LOADER_FILENAME_PART3, 7(%di)
- jne FindVARSTORE
- movw 26(%di), %bx # bx = Start Cluster for EFILDR <----------------------------------
- testw %dx, %dx
- je FindNext # Efivar.bin is not loaded
- jmp FoundAll
-
-FindVARSTORE:
- ## if the file is not loader file, see if it's "EFIVAR BIN"
- cmpl $0x56494645, (%di) # Compare to "EFIV"
- jne FindNext
- cmpl $0x20205241, 4(%di) # Compare to "AR "
- jne FindNext
- cmpl $0x4e494220, 7(%di) # Compare to " BIN"
- jne FindNext
- movw %di, %dx # dx = Offset of Start Cluster for Efivar.bin <---------------------
- addw $26, %dx
- testw %bx, %bx
- je FindNext # Efildr is not loaded
- jmp FoundAll
-
-FindNext:
- # go to next find
- addw $FAT_DIRECTORY_ENTRY_SIZE, %di # Increment di
- subw $FAT_DIRECTORY_ENTRY_SIZE, %cx # Decrement cx
- # TODO: jump to FindVarStore if ...
- jne FindEFILDR
- jmp NotFoundAll
-
-FoundAll:
-FoundEFILDR:
- movw %bx, %cx # cx = Start Cluster for EFILDR <----------------------------------
- movw %cs, %ax # Destination = 2000:0000
- addw $0x2000, %ax
- movw %ax, %es
- xorw %di, %di
-ReadFirstClusterOfEFILDR:
- movw %cx, %ax # ax = StartCluster
- subw $2, %ax # ax = StartCluster - 2
- xorb %bh, %bh
- movb SectorsPerCluster(%bp), %bl # bx = SectorsPerCluster
- pushw %dx
- mulw %bx
- popw %dx # ax = (StartCluster - 2) * SectorsPerCluster
- addw (%bp), %ax # ax = FirstClusterLBA + (StartCluster-2)*SectorsPerCluster
- xorb %bh, %bh
- movb SectorsPerCluster(%bp), %bl # bx = Number of Sectors in a cluster
- pushw %es
- call ReadBlocks
- popw %ax
-JumpIntoFirstSectorOfEFILDR:
- movw %ax, JumpSegment(%bp)
-JumpFarInstruction:
- .byte 0xea
-JumpOffset:
- .word 0x000
-JumpSegment:
- .word 0x2000
-
-
-PrintString:
- movw $0xb800, %ax
- movw %ax, %es
- movw $0x7c0, %ax
- movw %ax, %ds
- movw $6, %cx
- movw $160, %di
- rep
- movsw
- ret
-# ****************************************************************************
-# ReadBlocks - Reads a set of blocks from a block device
-#
-# AX = Start LBA
-# BX = Number of Blocks to Read
-# ES:DI = Buffer to store sectors read from disk
-# ****************************************************************************
-
-# cx = Blocks
-# bx = NumberOfBlocks
-# si = StartLBA
-
-ReadBlocks:
- pusha
- addl LBAOffsetForBootSector(%bp), %eax # Add LBAOffsetForBootSector to Start LBA
- addl HiddenSectors(%bp), %eax # Add HiddenSectors to Start LBA
- movl %eax, %esi # esi = Start LBA
- movw %bx, %cx # cx = Number of blocks to read
-ReadCylinderLoop:
- movw $0x7bfc, %bp # bp = 0x7bfc
- movl %esi, %eax # eax = Start LBA
- xorl %edx, %edx # edx = 0
- movzwl (%bp), %ebx # bx = MaxSector
- divl %ebx # ax = StartLBA / MaxSector
- incw %dx # dx = (StartLBA % MaxSector) + 1
- subw %dx, %bx # bx = MaxSector - Sector
- incw %bx # bx = MaxSector - Sector + 1
- cmpw %bx, %cx # Compare (Blocks) to (MaxSector - Sector + 1)
- jg LimitTransfer
- movw %cx, %bx # bx = Blocks
-LimitTransfer:
- pushw %cx
- movb %dl, %cl # cl = (StartLBA % MaxSector) + 1 = Sector
- xorw %dx, %dx # dx = 0
- divw 2(%bp) # ax = ax / (MaxHead + 1) = Cylinder
- # dx = ax % (MaxHead + 1) = Head
-
- pushw %bx # Save number of blocks to transfer
- movb %dl, %dh # dh = Head
- movw $0x7c00, %bp # bp = 0x7c00
- movb PhysicalDrive(%bp), %dl # dl = Drive Number
- movb %al, %ch # ch = Cylinder
- movb %bl, %al # al = Blocks
- movb $2, %ah # ah = Function 2
- movw %di, %bx # es:bx = Buffer address
- int $0x13
- jc DiskError
- popw %bx
- popw %cx
- movzwl %bx, %ebx
- addl %ebx, %esi # StartLBA = StartLBA + NumberOfBlocks
- subw %bx, %cx # Blocks = Blocks - NumberOfBlocks
- movw %es, %ax
- shlw $(BLOCK_SHIFT-4), %bx
- addw %bx, %ax
- movw %ax, %es # es:di = es:di + NumberOfBlocks*BLOCK_SIZE
- cmpw $0, %cx
- jne ReadCylinderLoop
- popa
- ret
-
-# ****************************************************************************
-# ERROR Condition:
-# ****************************************************************************
-NotFoundAll:
- ## if we found EFILDR, continue
- testw %bx, %bx
- jne FoundEFILDR
-BadBootSector:
-DiskError:
- movw $ErrorString, %si
- call PrintString
-Halt:
- jmp Halt
-
-StartString:
- .byte 'B', 0x0c, 'S', 0x0c, 't', 0x0c, 'a', 0x0c, 'r', 0x0c, 't', 0x0c
-ErrorString:
- .byte 'B', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, 'o', 0x0c, 'r', 0x0c
-
-# ****************************************************************************
-# LBA Offset for BootSector, need patched by tool for HD boot.
-# ****************************************************************************
-
- .org 0x01fa
-LBAOffsetForBootSector:
- .long 0x0
-
-# ****************************************************************************
-# Sector Signature
-# ****************************************************************************
-
- .org 0x01fe
-SectorSignature:
- .word 0xaa55 # Boot Sector Signature
-
-
-
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