diff options
| author | gikidy <gikidy@6f19259b-4bc3-4df7-8a09-765794883524> | 2009-02-20 03:11:41 +0000 |
|---|---|---|
| committer | gikidy <gikidy@6f19259b-4bc3-4df7-8a09-765794883524> | 2009-02-20 03:11:41 +0000 |
| commit | 819958c65f8d1674899c8b85ed3d4687ee381f8c (patch) | |
| tree | 09376ef148eda54b0f0038aa8c124b08e4332639 /DuetPkg/BootSector | |
| parent | 32f9b796d3bb05f608d87d49e691249e5f04d13e (diff) | |
| download | edk2-819958c65f8d1674899c8b85ed3d4687ee381f8c.tar.gz edk2-819958c65f8d1674899c8b85ed3d4687ee381f8c.tar.bz2 edk2-819958c65f8d1674899c8b85ed3d4687ee381f8c.zip | |
Port Intel .asm to GNU .S
These .S files now is not for compiler but for us to control the version.
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@7549 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'DuetPkg/BootSector')
| -rw-r--r-- | DuetPkg/BootSector/Mbr.S | 258 | ||||
| -rw-r--r-- | DuetPkg/BootSector/bootsect.S | 289 | ||||
| -rw-r--r-- | DuetPkg/BootSector/bs16.S | 289 | ||||
| -rw-r--r-- | DuetPkg/BootSector/start.S | 916 |
4 files changed, 1752 insertions, 0 deletions
diff --git a/DuetPkg/BootSector/Mbr.S b/DuetPkg/BootSector/Mbr.S new file mode 100644 index 0000000000..e69fb99ac9 --- /dev/null +++ b/DuetPkg/BootSector/Mbr.S @@ -0,0 +1,258 @@ +#------------------------------------------------------------------------------ +#* +#* Copyright 2006 - 2007, Intel Corporation +#* All rights reserved. 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. +#* +#* Mbr.asm +#* +#* Abstract: +#* +#------------------------------------------------------------------------------ + +.equ BLOCK_SIZE, 0x0200 +.equ BLOCK_MASK, 0x01ff +.equ BLOCK_SHIFT, 9 + +# **************************************************************************** +# Code loaded by BIOS at 0x0000:0x7C00 +# **************************************************************************** + +.org 0x0 +Start: + +# **************************************************************************** +# Start Print +# **************************************************************************** + + movw $0xb800, %ax + movw %ax, %es + movw $0x7c0, %ax + movw %ax, %ds + leaw %cs:StartString, %si + movw $10, %cx + movw $160, %di + rep + movsw + +# **************************************************************************** +# Print over +# **************************************************************************** + +# **************************************************************************** +# Initialize segment registers and copy code at 0x0000:0x7c00 to 0x0000:0x0600 +# **************************************************************************** + xorw %ax, %ax # AX = 0x0000 + movw $0x7c00, %bx # BX = 0x7C00 + movw $0x600, %bp # BP = 0x0600 + movw RelocatedStart, %si # SI = Offset(RelocatedStart) + movw $0x200, %cx # CX = 0x0200 + subw %si, %cx # CS = 0x0200 - Offset(RelocatedStart) + leaw (%bp,%si,), %di # DI = 0x0600 + Offset(RelocatedStart) + leaw (%bx,%si,), %si # BX = 0x7C00 + Offset(RelocatedStart) + movw %ax, %ss # SS = 0x0000 + movw %bx, %sp # SP = 0x7C00 + movw %ax, %es # ES = 0x0000 + movw %ax, %ds # DS = 0x0000 + pushw %ax # PUSH 0x0000 + pushw %di # PUSH 0x0600 + Offset(RelocatedStart) + cld # Clear the direction flag + rep + movsb # Copy 0x0200 bytes from 0x7C00 to 0x0600 + retl # JMP 0x0000:0x0600 + Offset(RelocatedStart) + +# **************************************************************************** +# Code relocated to 0x0000:0x0600 +# **************************************************************************** + +RelocatedStart: +# **************************************************************************** +# Get Driver Parameters to 0x0000:0x7BFC +# **************************************************************************** + + xorw %ax, %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 + +# **************************************************************************** +# Read Target DBR from hard disk to 0x0000:0x7C00 +# **************************************************************************** + + xorw %ax, %ax + movb MbrPartitionIndicator(%bp), %al # AX = MbrPartitionIndex + cmpb $0xff, %al # 0xFF means do legacy MBR boot + jnz EfiDbr +LegacyMbr: + movl $0x0000600, %eax # Assume LegacyMBR is backuped in Sector 6 + jmp StartReadTo7C00 # EAX = Header/Sector/Tracker/Zero + +EfiDbr: + cmpb $4, %al # MbrPartitionIndex should < 4 + jae BadDbr + shlw $4, %ax # AX = MBREntrySize * Index + addw $0x1be, %ax # AX = MBREntryOffset + movw %ax, %di # DI = MBREntryOffset + + # Here we don't use the C/H/S information provided by Partition table + # but calculate C/H/S from LBA ourselves + # Ci: Cylinder number + # Hi: Header number + # Si: Sector number + movl %es:8(%bp,%di,), %eax # Start LBA + movl %eax, %edx + shrl $16, %edx # DX:AX = Start LBA + # = Ci * (H * S) + Hi * S + (Si - 1) + + # Calculate C/H/S according to LBA + movw $0x7bfa, %bp + divw 2(%bp) # AX = Hi + H*Ci + # DX = Si - 1 + incw %dx # DX = Si + pushw %dx # 0000:7bfa = Si <---- + xorw %dx, %dx # DX:AX = Hi + H*Ci + divw 4(%bp) # AX = Ci <---- + # DX = Hi <---- + +StartReadTo7C00: + + movb (%bp), %cl # Si + movb %al, %ch # Ci[0-7] + orb %ah, %cl # Ci[8,9] + movw $0x7c00, %bx # ES:BX = 0000:7C00h + movb $0x2, %ah # Function 02h + movb $1, %al # 1 Sector + movb %dl, %dh # Hi + movw $0x600, %bp + movb PhysicalDrive(%bp), %dl # Drive number + int $0x13 + jc BadDbr + + + +# **************************************************************************** +# Transfer control to BootSector - Jump to 0x0000:0x7C00 +# **************************************************************************** + xorw %ax, %ax + pushw %ax # PUSH 0x0000 - Segment + movw $0x7c00, %di + pushw %di # PUSH 0x7C00 - Offset + retl # JMP 0x0000:0x7C00 + +# **************************************************************************** +# ERROR Condition: +# **************************************************************************** + +BadDbr: + pushw %ax + movw $0xb800, %ax + movw %ax, %es + movw $0x60, %ax + movw %ax, %ds + leaw %cs:ErrorString, %si + movw $320, %di + popw %ax + call A2C + movb %ah, 16(%si) + movb %al, 18(%si) + movw $10, %cx + rep + movsw +Halt: + jmp Halt + +StartString: +.byte 'M', 0x0c, 'B', 0x0c, 'R', 0x0c, ' ', 0x0c, 'S', 0x0c, 't', 0x0c, 'a', 0x0c, 'r', 0x0c, 't', 0x0c, '!', 0x0c +ErrorString: +.byte 'M', 0x0c, 'B', 0x0c, 'R', 0x0c, ' ', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, ':', 0x0c, '?', 0x0c, '?', 0x0c + +# **************************************************************************** +# A2C - convert Ascii code stored in AH to character stored in AX +# **************************************************************************** +A2C: + movb %ah, %al + shrb $4, %ah + andb $0xF, %al + addb '0', %ah + addb '0', %al + + cmpb '9', %ah + jle A2C_L1 + addb $7, %ah +A2C_L1: + + cmpb '9', %al + jle A2C_L2 + addb $7, %al +A2C_L2: + ret + + +# **************************************************************************** +# PhysicalDrive - Used to indicate which disk to be boot +# Can be patched by tool +# **************************************************************************** +.org 0x01B6 +PhysicalDrive: .byte 0x80 + +# **************************************************************************** +# MbrPartitionIndicator - Used to indicate which MBR partition to be boot +# Can be patched by tool +# OxFF means boot to legacy MBR. (LBA OFFSET 6) +# **************************************************************************** +.org 0x01B7 +MbrPartitionIndicator: .byte 0 + +# **************************************************************************** +# Unique MBR signature +# **************************************************************************** +.org 0x01B8 + .ascii "DUET" + +# **************************************************************************** +# Unknown +# **************************************************************************** +.org 0x01BC + .word 0 + +# **************************************************************************** +# MBR Entry - To be patched +# **************************************************************************** +.org 0x01BE + .long 0,0,0,0 +.org 0x01CE + .long 0,0,0,0 +.org 0x01DE + .long 0,0,0,0 +.org 0x01EE + .long 0,0,0,0 + +# **************************************************************************** +# Sector Signature +# **************************************************************************** + +.org 0x01FE +SectorSignature: + .word 0xaa55 # Boot Sector Signature + + + diff --git a/DuetPkg/BootSector/bootsect.S b/DuetPkg/BootSector/bootsect.S new file mode 100644 index 0000000000..edf941bcb3 --- /dev/null +++ b/DuetPkg/BootSector/bootsect.S @@ -0,0 +1,289 @@ +#------------------------------------------------------------------------------
+#*
+#* Copyright 2006 - 2007, Intel Corporation
+#* All rights reserved. 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.
+#*
+#* bootsect.asm
+#*
+#* Abstract:
+#*
+#------------------------------------------------------------------------------
+
+ #.MODEL small
+ .stack:
+ .486p:
+ .code:
+
+.equ FAT_DIRECTORY_ENTRY_SIZE, 0x020
+.equ FAT_DIRECTORY_ENTRY_SHIFT, 5
+.equ BLOCK_SIZE, 0x0200
+.equ BLOCK_MASK, 0x01ff
+.equ BLOCK_SHIFT, 9
+ # "EFILDR_____"
+.equ LOADER_FILENAME_PART1, 0x04c494645 # "EFIL"
+.equ LOADER_FILENAME_PART2, 0x020205244 # "DR__"
+.equ LOADER_FILENAME_PART3, 0x020202020 # "____"
+
+ .org 0x0
+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
+PhysicalDrive: .byte 0 # PhysicalDriveNumber - 8 bits - ignored
+CurrentHead: .byte 0 # Current Head - 8 bits
+Signature: .byte 0 # Signature - 8 bits - ignored
+VolId: .ascii " " # Volume Serial Number- 4 bytes
+FatLabel: .ascii " " # Label - 11 bytes
+SystemId: .ascii "FAT12 " # SystemId - 8 bytes
+
+BootSectorEntryPoint:
+ #ASSUME ds:@code
+ #ASSUME ss:@code
+
+# ****************************************************************************
+# Start Print
+# ****************************************************************************
+ leaw %cs: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 SectorsPerFat(%bp) # ax = NoFats * SectorsPerFat
+ addw ReservedSectors(%bp), %ax # ax = NoFats * SectorsPerFat + ReservedSectors = RootLBA
+ pushw %ds
+ popw %es
+ xorw %di, %di # Store directory in es:di = 1000:0000
+ call ReadBlocks # Read entire Root Directory
+ addw %bx, %ax # ax = NoFats * SectorsPerFat + ReservedSectors + RootDirSectors = FirstClusterLBA (FirstDataSector)
+ movw %ax, (%bp) # Save FirstClusterLBA (FirstDataSector) for later use
+
+ # 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) # Compare to "EFIL"
+ 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 $7, %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:
+ leaw %cs:ErrorString, %si
+ call PrintString
+Halt:
+ jmp Halt
+
+StartString:
+ .byte 'B', 0x0c, 'S', 0x0c, 't', 0x0c, 'a', 0x0c, 'r', 0x0c, 't', 0x0c, '!', 0x0c
+ErrorString:
+ .byte 'B', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, 'o', 0x0c, 'r', 0x0c, '!', 0x0c
+
+# ****************************************************************************
+# LBA Offset for BootSector, need patched by tool for HD boot.
+# ****************************************************************************
+
+ # .org 0x01fa # Comment it for pass build. Should optimise code size.
+LBAOffsetForBootSector:
+ .long 0x0
+
+# ****************************************************************************
+# Sector Signature
+# ****************************************************************************
+
+ # .org 0x01fe # Comment it for pass build.
+SectorSignature:
+ .word 0xaa55 # Boot Sector Signature
+
+
+
diff --git a/DuetPkg/BootSector/bs16.S b/DuetPkg/BootSector/bs16.S new file mode 100644 index 0000000000..b2ade2c734 --- /dev/null +++ b/DuetPkg/BootSector/bs16.S @@ -0,0 +1,289 @@ +#------------------------------------------------------------------------------
+#*
+#* Copyright 2006 - 2007, Intel Corporation
+#* All rights reserved. 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.
+#*
+#* bs16.asm
+#*
+#* Abstract:
+#*
+#------------------------------------------------------------------------------
+
+ #.MODEL small
+ .stack:
+ .486p:
+ .code:
+
+.equ FAT_DIRECTORY_ENTRY_SIZE, 0x020
+.equ FAT_DIRECTORY_ENTRY_SHIFT, 5
+.equ BLOCK_SIZE, 0x0200
+.equ BLOCK_MASK, 0x01ff
+.equ BLOCK_SHIFT, 9
+ # "EFILDR_____"
+.equ LOADER_FILENAME_PART1, 0x04c494645 # "EFIL"
+.equ LOADER_FILENAME_PART2, 0x036315244 # "DR16"
+.equ LOADER_FILENAME_PART3, 0x020202036 # "6___"
+
+ .org 0x0
+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
+PhysicalDrive: .byte 0 # PhysicalDriveNumber - 8 bits - ignored
+CurrentHead: .byte 0 # Current Head - 8 bits
+Signature: .byte 0 # Signature - 8 bits - ignored
+VolId: .ascii " " # Volume Serial Number- 4 bytes
+FatLabel: .ascii " " # Label - 11 bytes
+SystemId: .ascii "FAT12 " # SystemId - 8 bytes
+
+BootSectorEntryPoint:
+ #ASSUME ds:@code
+ #ASSUME ss:@code
+
+# ****************************************************************************
+# Start Print
+# ****************************************************************************
+ leaw %cs: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 SectorsPerFat(%bp) # ax = NoFats * SectorsPerFat
+ addw ReservedSectors(%bp), %ax # ax = NoFats * SectorsPerFat + ReservedSectors = RootLBA
+ pushw %ds
+ popw %es
+ xorw %di, %di # Store directory in es:di = 1000:0000
+ call ReadBlocks # Read entire Root Directory
+ addw %bx, %ax # ax = NoFats * SectorsPerFat + ReservedSectors + RootDirSectors = FirstClusterLBA (FirstDataSector)
+ movw %ax, (%bp) # Save FirstClusterLBA (FirstDataSector) for later use
+
+ # 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) # Compare to "EFIL"
+ 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 $7, %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:
+ leaw %cs:ErrorString, %si
+ call PrintString
+Halt:
+ jmp Halt
+
+StartString:
+ .byte 'B', 0x0c, 'S', 0x0c, 't', 0x0c, 'a', 0x0c, 'r', 0x0c, 't', 0x0c, '!', 0x0c
+ErrorString:
+ .byte 'B', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, 'o', 0x0c, 'r', 0x0c, '!', 0x0c
+
+# ****************************************************************************
+# LBA Offset for BootSector, need patched by tool for HD boot.
+# ****************************************************************************
+
+ # .org 0x01fa # Comment it for pass build. Should optimise code size.
+LBAOffsetForBootSector:
+ .long 0x0
+
+# ****************************************************************************
+# Sector Signature
+# ****************************************************************************
+
+ # .org 0x01fe # Comment it for pass build. Should optimise code size.
+SectorSignature:
+ .word 0xaa55 # Boot Sector Signature
+
+
+
diff --git a/DuetPkg/BootSector/start.S b/DuetPkg/BootSector/start.S new file mode 100644 index 0000000000..4b65ff038e --- /dev/null +++ b/DuetPkg/BootSector/start.S @@ -0,0 +1,916 @@ +#------------------------------------------------------------------------------
+#*
+#* Copyright 2006 - 2007, Intel Corporation
+#* All rights reserved. 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.
+#*
+#* start.S
+#*
+#* Abstract:
+#*
+#------------------------------------------------------------------------------
+
+
+.equ FAT_DIRECTORY_ENTRY_SIZE, 0x020
+.equ FAT_DIRECTORY_ENTRY_SHIFT, 5
+.equ BLOCK_SIZE, 0x0200
+.equ BLOCK_MASK, 0x01ff
+.equ BLOCK_SHIFT, 9
+
+ .org 0x0
+Ia32Jump:
+ jmp BootSectorEntryPoint # JMP inst - 3 bytes
+ nop
+
+OemId: .ascii "INTEL " # OemId - 8 bytes
+
+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
+PhysicalDrive: .byte 0 # PhysicalDriveNumber - 8 bits - ignored
+CurrentHead: .byte 0 # Current Head - 8 bits
+Signature: .byte 0 # Signature - 8 bits - ignored
+VolId: .ascii " " # Volume Serial Number- 4 bytes
+FatLabel: .ascii " " # Label - 11 bytes
+SystemId: .ascii "FAT12 " # SystemId - 8 bytes
+
+BootSectorEntryPoint:
+ #ASSUME ds:@code
+ #ASSUME ss:@code
+ # ds = 1000, es = 2000 + x (size of first cluster >> 4)
+ # cx = Start Cluster of EfiLdr
+ # dx = Start Cluster of Efivar.bin
+
+# Re use the BPB data stored in Boot Sector
+ movw $0x7c00, %bp
+
+ pushw %cx
+# Read Efivar.bin
+# 1000:dx = DirectoryEntry of Efivar.bin -> BS.com has filled already
+ movw $0x1900, %ax
+ movw %ax, %es
+ testw %dx, %dx
+ jnz CheckVarStoreSize
+
+ movb $1, %al
+NoVarStore:
+ pushw %es
+# Set the 5th byte start @ 0:19000 to non-zero indicating we should init var store header in DxeIpl
+ movb %al, %es:($4)
+ jmp SaveVolumeId
+
+CheckVarStoreSize:
+ movw %dx, %di
+ cmpl $0x4000, %ds:2(%di)
+ movb $2, %al
+ jne NoVarStore
+
+LoadVarStore:
+ movb $0, %al
+ movb %al, %es:($4)
+ movw (%di), %cx
+# ES:DI = 1500:0
+ xorw %di, %di
+ pushw %es
+ movw $0x1500, %ax
+ movw %ax, %es
+ call ReadFile
+SaveVolumeId:
+ popw %es
+ movw VolId(%bp), %ax
+ movw %ax, %es:($0) # Save Volume Id to 0:19000. we will find the correct volume according to this VolumeId
+ movw VolId+2(%bp), %ax
+ movw %ax, %es:($2)
+
+# Read Efildr
+ popw %cx
+# cx = Start Cluster of Efildr -> BS.com has filled already
+# ES:DI = 2000:0, first cluster will be read again
+ xorw %di, %di # di = 0
+ movw $0x2000, %ax
+ movw %ax, %es
+ call ReadFile
+ movw %cs, %ax
+ movw %ax, %cs:JumpSegment
+
+JumpFarInstruction:
+ .byte 0xea
+JumpOffset:
+ .word 0x200
+JumpSegment:
+ .word 0x2000
+
+
+
+# ****************************************************************************
+# ReadFile
+#
+# Arguments:
+# CX = Start Cluster of File
+# ES:DI = Buffer to store file content read from disk
+#
+# Return:
+# (ES << 4 + DI) = end of file content Buffer
+#
+# ****************************************************************************
+ReadFile:
+# si = NumberOfClusters
+# cx = ClusterNumber
+# dx = CachedFatSectorNumber
+# ds:0000 = CacheFatSectorBuffer
+# es:di = Buffer to load file
+# bx = NextClusterNumber
+ pusha
+ movw $1, %si # NumberOfClusters = 1
+ pushw %cx # Push Start Cluster onto stack
+ movw $0xfff, %dx # CachedFatSectorNumber = 0xfff
+FatChainLoop:
+ movw %cx, %ax # ax = ClusterNumber
+ andw $0xff8, %ax # ax = ax & 0xff8
+ cmpw $0xff8, %ax # See if this is the last cluster
+ je FoundLastCluster # Jump if last cluster found
+ movw %cx, %ax # ax = ClusterNumber
+ shlw %ax # ax = ClusterNumber * 2
+ addw %cx, %ax # ax = ClusterNumber * 2 + ClusterNumber = ClusterNumber * 3
+ shrw %ax # FatOffset = ClusterNumber*3 / 2
+ pushw %si # Save si
+ movw %ax, %si # si = FatOffset
+ shrw %ax # ax = FatOffset >> BLOCK_SHIFT
+ addw ReservedSectors(%bp), %ax # ax = FatSectorNumber = ReservedSectors + (FatOffset >> BLOCK_OFFSET)
+ andw BLOCK_MASK,%si # si = FatOffset & BLOCK_MASK
+ cmpw %dx, %ax # Compare FatSectorNumber to CachedFatSectorNumber
+ je SkipFatRead
+ movw $2, %bx
+ pushw %es
+ pushw %ds
+ popw %es
+ call ReadBlocks # Read 2 blocks starting at AX storing at ES:DI
+ popw %es
+ movw %ax, %dx # CachedFatSectorNumber = FatSectorNumber
+SkipFatRead:
+ movw (%si), %bx # bx = NextClusterNumber
+ movw %cx, %ax # ax = ClusterNumber
+ andw $1, %ax # See if this is an odd cluster number
+ je EvenFatEntry
+ shrw $4, %bx # NextClusterNumber = NextClusterNumber >> 4
+EvenFatEntry:
+ andw $0xfff, %bx # Strip upper 4 bits of NextClusterNumber
+ popw %si # Restore si
+ decw %bx # bx = NextClusterNumber - 1
+ cmpw %cx, %bx # See if (NextClusterNumber-1)==ClusterNumber
+ jne ReadClusters
+ incw %bx # bx = NextClusterNumber
+ incw %si # NumberOfClusters++
+ movw %bx, %cx # ClusterNumber = NextClusterNumber
+ jmp FatChainLoop
+ReadClusters:
+ incw %bx
+ popw %ax # ax = StartCluster
+ pushw %bx # StartCluster = NextClusterNumber
+ movw %bx, %cx # ClusterNumber = NextClusterNumber
+ 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 %ax # save start sector
+ movw %si, %ax # ax = NumberOfClusters
+ mulw %bx # ax = NumberOfClusters * SectorsPerCluster
+ movw %ax, %bx # bx = Number of Sectors
+ popw %ax # ax = Start Sector
+ call ReadBlocks
+ movw $1, %si # NumberOfClusters = 1
+ jmp FatChainLoop
+FoundLastCluster:
+ popw %cx
+ popa
+ 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
+
+ movw (%bp), %bx # bx = MaxSector
+ 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 %ax # save ax
+ movw %es, %ax # ax = es
+ shrw %ax # ax = Number of blocks into mem system
+ andw $0x7f, %ax # ax = Number of blocks into current seg
+ addw %bx, %ax # ax = End Block number of transfer
+ cmpw $0x80, %ax # See if it crosses a 64K boundry
+ jle NotCrossing64KBoundry # Branch if not crossing 64K boundry
+ subw $0x80, %ax # ax = Number of blocks past 64K boundry
+ subw %ax, %bx # Decrease transfer size by block overage
+NotCrossing64KBoundry:
+ popw %ax # restore ax
+
+ 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 %bx
+ addw %bx, %ax
+ movw %ax, %es # es:di = es:di + NumberOfBlocks*BLOCK_SIZE
+ cmpw $0, %cx
+ jne ReadCylinderLoop
+ popa
+ ret
+
+DiskError:
+ pushw %cs
+ popw %ds
+ leaw %cs:ErrorString, %si
+ movw $7, %cx
+ jmp PrintStringAndHalt
+
+PrintStringAndHalt:
+ movw $0xb800, %ax
+ movw %ax, %es
+ movw $160, %di
+ rep
+ movsw
+Halt:
+ jmp Halt
+
+ErrorString:
+ .byte 'S', 0x0c, 'E', 0x0c, 'r', 0x0c, 'r', 0x0c, 'o', 0x0c, 'r', 0x0c, '!',0x0c
+
+ #.org 0x0242 # For Code size overflow, Modified this just for pass build
+LBAOffsetForBootSector:
+ .long 0x0
+
+ #.org 0x0227 # For Code size overflow, Modified this just for pass build
+ .word 0xaa55
+
+#******************************************************************************
+#******************************************************************************
+#******************************************************************************
+
+.equ DELAY_PORT, 0x0ed # Port to use for 1uS delay
+.equ KBD_CONTROL_PORT, 0x060 # 8042 control port
+.equ KBD_STATUS_PORT, 0x064 # 8042 status port
+.equ WRITE_DATA_PORT_CMD, 0x0d1 # 8042 command to write the data port
+.equ ENABLE_A20_CMD, 0x0df # 8042 command to enable A20
+
+ #.org 0x200
+ jmp start
+Em64String:
+ .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
+
+start:
+ movw %cs, %ax
+ movw %ax, %ds
+ movw %ax, %es
+ movw %ax, %ss
+ movw $MyStack, %sp
+
+# mov ax,0b800h
+# mov es,ax
+# mov byte ptr es:[160],'a'
+# mov ax,cs
+# mov es,ax
+
+ movl $0, %ebx
+ leal MemoryMap, %edi
+MemMapLoop:
+ movl $0xe820, %eax
+ movl $20, %ecx
+ movl 0x534d4150, %edx # SMAP
+ int $0x15
+ jc MemMapDone
+ addl $20, %edi
+ cmpl $0, %ebx
+ je MemMapDone
+ jmp MemMapLoop
+MemMapDone:
+ leal MemoryMap, %eax
+ subl %eax, %edi # Get the address of the memory map
+ movl %edi, MemoryMapSize # Save the size of the memory map
+
+ xorl %ebx, %ebx
+ movw %cs, %bx # BX=segment
+ shll $4, %ebx # BX="linear" address of segment base
+ leal GDT_BASE(%ebx), %eax #
+ movl %eax, (gdtr + 2) #
+ leal IDT_BASE(%ebx), %eax #
+ movl %eax, (idtr + 2) #
+ leal MemoryMapSize(%ebx), %edx #
+
+ addl $0x1000, %ebx # Source of EFI32
+ movl %ebx, JUMP+2
+ addl $0x1000, %ebx
+ movl %ebx, %esi # Source of EFILDR32
+
+# mov ax,0b800h
+# mov es,ax
+# mov byte ptr es:[162],'b'
+# mov ax,cs
+# mov es,ax
+
+#
+# Enable A20 Gate
+#
+
+ movw $0x2401, %ax # Enable A20 Gate
+ int $0x15
+ jnc A20GateEnabled # Jump if it suceeded
+
+#
+# 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
+ mov $WRITE_DATA_PORT_CMD, %al # 8042 cmd to write output port
+ out %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
+ mov $ENABLE_A20_CMD, %al # gate address bit 20 on
+ out %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:
+
+#
+# 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
+
+ movl $0x008, %eax # Flat data descriptor
+ movl $0x00400000, %ebp # Destination of EFILDR32
+ movl $0x00070000, %ebx # Length of copy
+
+JUMP:
+# jmp far 0010:00020000
+ .byte 0x66
+ .byte 0xea
+ .long 0x00020000
+ .word 0x0010
+
+Empty8042InputBuffer:
+ movw $0, %cx
+Empty8042Loop:
+ outw %ax, $DELAY_PORT # Delay 1us
+ in $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
+##############################################################################
+
+ .align 0x2
+
+ gdtr: .long GDT_END - GDT_BASE - 1 # GDT limit
+ .long 0 # (GDT base gets set above)
+##############################################################################
+# global descriptor table (GDT)
+##############################################################################
+
+ .align 0x2
+
+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:
+
+ .align 0x2
+
+
+
+idtr: .long 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
+ .align 0x2
+
+IDT_BASE:
+# divide by zero (INT 0)
+.equ DIV_ZERO_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # 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
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# NMI (INT 2)
+.equ NMI_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# soft breakpoint (INT 3)
+.equ BREAKPOINT_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# overflow (INT 4)
+.equ OVERFLOW_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # 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
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # 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
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # 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
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # 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
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # 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
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# invalid TSS (INT 0x0a)
+.equ INVALID_TSS_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# segment not present (INT 0x0b)
+.equ SEG_NOT_PRESENT_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# stack fault (INT 0x0c)
+.equ STACK_FAULT_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# general protection (INT 0x0d)
+.equ GP_FAULT_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# page fault (INT 0x0e)
+.equ PAGE_FAULT_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# Intel reserved - do not use (INT 0x0f)
+.equ RSVD_INTR_SEL2, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# floating point error (INT 0x10)
+.equ FLT_POINT_ERR_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long SYS_CODE_SEL # selector 15:0
+ .byte 0 # 0 for interrupt gate
+ .byte 0x0e | 0x80 # type = 386 interrupt gate, present
+ .word 0 # offset 31:16
+
+# alignment check (INT 0x11)
+.equ ALIGNMENT_CHECK_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x12)
+.equ MACHINE_CHECK_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x13)
+.equ SIMD_EXCEPTION_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 # db (85 * 8) dup(0)
+
+# IRQ 0 (System timer) - (INT 0x68)
+.equ IRQ0_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x69)
+.equ IRQ1_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x6a)
+.equ IRQ2_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x6b)
+.equ IRQ3_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x6c)
+.equ IRQ4_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x6d)
+.equ IRQ5_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x6e)
+.equ IRQ6_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x6f)
+.equ IRQ7_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x70)
+.equ IRQ8_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x71)
+.equ IRQ9_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x72)
+.equ IRQ10_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x73)
+.equ IRQ11_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x74)
+.equ IRQ12_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x75)
+.equ IRQ13_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x76)
+.equ IRQ14_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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 0x77)
+.equ IRQ15_SEL, .-IDT_BASE
+ .word 0 # offset 15:0
+ .long 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:
+
+ .align 0x2
+
+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
+
+
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