diff --git a/sys/boot/i386/boot0/Makefile b/sys/boot/i386/boot0/Makefile index 434691e798aef2..e6181417bcd0ee 100644 --- a/sys/boot/i386/boot0/Makefile +++ b/sys/boot/i386/boot0/Makefile @@ -31,6 +31,14 @@ boot0.o: boot0.s ${AS} ${AFLAGS} --defsym FLAGS=${BOOT_BOOT0_FLAGS} \ --defsym TICKS=${BOOT_BOOT0_TICKS} ${.IMPSRC} -o ${.TARGET} -CLEANFILES+= boot0.out boot0.o +boot0sio: boot0sio.o + ${LD} -N -e start -Ttext ${BOOT_BOOT0_ORG} -o boot0sio.out boot0sio.o + objcopy -S -O binary boot0sio.out ${.TARGET} + +boot0sio.o: boot0sio.s + ${AS} ${AFLAGS} --defsym FLAGS=${BOOT_BOOT0_FLAGS} \ + --defsym TICKS=${BOOT_BOOT0_TICKS} ${.IMPSRC} -o ${.TARGET} + +CLEANFILES+= boot0.out boot0.o boot0sio.out boot0sio.o .include diff --git a/sys/boot/i386/boot0/boot0.S b/sys/boot/i386/boot0/boot0.S new file mode 100644 index 00000000000000..47ddfbd824dfd6 --- /dev/null +++ b/sys/boot/i386/boot0/boot0.S @@ -0,0 +1,437 @@ +# +# Copyright (c) 2002 Bruce M. Simpson +# Copyright (c) 1998 Robert Nordier +# All rights reserved. +# +# Redistribution and use in source and binary forms are freely +# permitted provided that the above copyright notice and this +# paragraph and the following disclaimer are duplicated in all +# such forms. +# +# This software is provided "AS IS" and without any express or +# implied warranties, including, without limitation, the implied +# warranties of merchantability and fitness for a particular +# purpose. +# + +# $FreeBSD$ + +# A 512-byte boot manager which uses a 9600 baud serial console on COM1. + + .set NHRDRV,0x475 # Number of hard drives + .set ORIGIN,0x600 # Execution address + .set FAKE,0x800 # Partition entry + .set LOAD,0x7c00 # Load address + + .set PRT_OFF,0x1be # Partition table + + .set TBL0SZ,0x3 # Table 0 size + .set TBL1SZ,0xc # Table 1 size + + .set MAGIC,0xaa55 # Magic: bootable + .set B0MAGIC,0xbb66 # Identification + + .set KEY_ENTER,0x1c # Enter key scan code + .set KEY_F1,0x3b # F1 key scan code + + .set ASCII_BEL,0x07 # ASCII code for + .set ASCII_CR,0x0D # ASCII code for + .set ASCII_1,0x31 # ASCII code for '1' + +# +# Addresses in the sector of embedded data values. +# Accessed with negative offsets from the end of the relocated sector (%ebp). +# + .set _NXTDRV,-0x48 # Next drive + .set _OPT,-0x47 # Default option + .set _SETDRV,-0x46 # Drive to force + .set _FLAGS,-0x45 # Flags + .set _TICKS,-0x44 # Timeout ticks + .set _FAKE,0x0 # Fake partition entry + .set _MNUOPT,0xc # Menu options + + .globl start # Entry point + .code16 # This runs in real mode + +# +# Initialise segments and registers to known values. +# segments start at 0. +# The stack is immediately below the address we were loaded to. +# +start: cld # String ops inc + xorw %ax,%ax # Zero + movw %ax,%es # Address + movw %ax,%ds # data + movw %ax,%ss # Set up + movw $LOAD,%sp # stack + +# +# Copy this code to the address it was linked for +# + movw %sp,%si # Source + movw $start,%di # Destination + movw $0x100,%cx # Word count + rep # Relocate + movsw # code +# +# Set address for variable space beyond code, and clear it. +# Notice that this is also used to point to the values embedded in the block, +# by using negative offsets. +# + movw %di,%bp # Address variables + movb $0x8,%cl # Words to clear + rep # Zero + stosw # them +# +# Relocate to the new copy of the code. +# + incb -0xe(%di) # Sector number + jmp main-LOAD+ORIGIN # To relocated code + +# +# Initialize the serial port. +# Must save DX (contains drive number) +# +main: pushw %dx # Save + xorw %dx,%dx # Port: COM1 + movb $0xE3,%al # 9600 8-N-1 + movb $0x00,%ah # BIOS: Set COM Port + int $0x14 # Parameters + popw %dx # Restore +# +# Check what flags were loaded with us, specifically, Use a predefined Drive. +# If what the bios gives us is bad, use the '0' in the block instead, as well. +# + testb $0x20,_FLAGS(%bp) # Set number drive? + jnz main.1 # Yes + testb %dl,%dl # Drive number valid? + js main.2 # Possibly (0x80 set) +main.1: movb _SETDRV(%bp),%dl # Drive number to use +# +# Whatever we decided to use, now store it into the fake +# partition entry that lives in the data space above us. +# +main.2: movb %dl,_FAKE(%bp) # Save drive number + callw putn # To new line + pushw %dx # Save drive number +# +# Start out with a pointer to the 4th byte of the first table entry +# so that after 4 iterations it's beyond the end of the sector. +# and beyond a 256 byte boundary and has overflowed 8 bits (see next comment). +# (remember that the table starts 2 bytes earlier than you would expect +# as the bootable flag is after it in the block) +# + movw $(partbl+0x4),%bx # Partition table (+4) + xorw %dx,%dx # Item number +# +# Loop around on the partition table, printing values until we +# pass a 256 byte boundary. The end of loop test is at main.5. +# +main.3: movb %ch,-0x4(%bx) # Zero active flag (ch == 0) + btw %dx,_FLAGS(%bp) # Entry enabled? + jnc main.5 # No +# +# If any of the entries in the table are +# the same as the 'type' in the slice table entry, +# then this is an empty or non bootable partition. Skip it. +# + movb (%bx),%al # Load type + movw $tables,%di # Lookup tables + movb $TBL0SZ,%cl # Number of entries + repne # Exclude + scasb # partition? + je main.5 # Yes +# +# Now scan the table of known types +# + movb $TBL1SZ,%cl # Number of entries + repne # Known + scasb # type? + jne main.4 # No +# +# If it matches get the matching element in the +# next array. if it doesn't, we are already +# pointing at its first element which points to a "?". +# + addw $TBL1SZ,%di # Adjust +main.4: movb (%di),%cl # Partition + addw %cx,%di # description + callw putx # Display it +main.5: incw %dx # Next item + addb $0x10,%bl # Next entry + jnc main.3 # Till done +# +# Passed a 256 byte boundary.. +# table is finished. +# Add one to the drive number and check it is valid, +# + popw %ax # Drive number + subb $0x80-0x1,%al # Does next + cmpb NHRDRV,%al # drive exist? (from BIOS?) + jb main.6 # Yes +# If not then if there is only one drive, +# Don't display drive as an option. +# + decw %ax # Already drive 0? + jz main.7 # Yes +# If it was illegal or we cycled through them, +# then go back to drive 0. +# + xorb %al,%al # Drive 0 +# +# Whatever drive we selected, make it an ascii digit and save it back +# to the "next drive" location in the loaded block in case we +# want to save it for next time. +# This also is part of the printed drive string so add 0x80 to indicate +# end of string. +# +main.6: addb $'0'|0x80,%al # Save next + movb %al,_NXTDRV(%bp) # drive number + movw $drive,%di # Display + callw putx # item +# +# Now that we've printed the drive (if we needed to), display a prompt. +# +main.7: movw $prompt,%si # Display + callw putstr # prompt + movb _OPT(%bp),%dl # Display + decw %si # default + callw putkey # key + +main.7_1: + xorb %ah,%ah # BIOS: Get + int $0x1a # system time + movw %dx,%si # Ticks when + addw _TICKS(%bp),%si # timeout + +# +# Check for a character on the serial port. +# + +main.8: xorw %dx,%dx # Use COM1 + movb $0x03,%ah # BIOS: Read COM + int $0x14 # Status + testb $0x01,%ah # Check line status + jnz main.11 # (bit 1 indicates input) + + xorb %ah,%ah # BIOS: Get + int $0x1a # system time + cmpw %si,%dx # Timeout? + jb main.8 # No + +# +# If timed out or defaulting, come here. +# +main.9: movb _OPT(%bp),%al # Load default + jmp main.12 # Join common code +# +# User's last try was bad, beep in displeasure. +# Since nothing was printed, just continue on as if the user +# hadn't done anything. This gives the effect of the user getting a beep +# for all bad keystrokes but no action until either the timeout +# occurs or the user hits a good key. +# +main.10: movb $ASCII_BEL,%al # Signal + callw putchr # error + jmp main.7_1 # Go back +# +# Check the character we just got on the serial port. +# If it's CR act as if timed out. +# +main.11: movb $0x02,%ah # BIOS: Receive + int $0x14 # COM Byte + + cmpb $ASCII_CR,%al # Enter pressed? + je main.9 # Yes +# +# Otherwise check if legal +# If not ask again. +# + subb $ASCII_1,%al # Less '1' ascii character + cmpb $0x4,%al # 1..5? + ja main.10 # No +# +# We have a selection. +# but if it's a bad selection go back to complain. +# The bits in MNUOPT were set when the options were printed. +# Anything not printed is not an option. +# +main.12: cbtw # Option + btw %ax,_MNUOPT(%bp) # enabled? + jnc main.10 # No +# +# Save the info in the original tables +# for rewriting to the disk. +# + movb %al,_OPT(%bp) # Save option + movw $FAKE,%si # Partition for write + movb (%si),%dl # Drive number + movw %si,%bx # Partition for read + cmpb $0x4,%al # 5 pressed? + pushf # Save + je main.13 # Yes + shlb $0x4,%al # Point to + addw $partbl,%ax # selected + xchgw %bx,%ax # partition + movb $0x80,(%bx) # Flag active +# +# If not asked to do a write-back (flags 0x40) don't do one. +# +main.13: pushw %bx # Save + testb $0x40,_FLAGS(%bp) # No updates? + jnz main.14 # Yes + movw $start,%bx # Data to write + movb $0x3,%ah # Write sector + callw intx13 # to disk +main.14: popw %si # Restore + popf # Restore +# +# If going to next drive, replace drive with selected one. +# Remember to un-ascii it. Hey 0x80 is already set, cool! +# + jne main.15 # If not 5 + movb _NXTDRV(%bp),%dl # Next drive + subb $'0',%dl # number XXX char val? +# +# load selected bootsector to the LOAD location in RAM. +# If it fails to read or isn't marked bootable, treat it +# as a bad selection. +# XXX what does %si carry? +# +main.15: movw $LOAD,%bx # Address for read + movb $0x2,%ah # Read sector + callw intx13 # from disk + jc main.10 # If error + cmpw $MAGIC,0x1fe(%bx) # Bootable? + jne main.10 # No + pushw %si # Save + movw $crlf,%si # Leave some + callw puts # space + popw %si # Restore + jmp *%bx # Invoke bootstrap +# +# Display routines +# + +putkey: movb $ASCII_1,%al # Prepare + addb %dl,%al # digit + jmp putstr.1 # Display the rest + +# +# Display the option and note that it is a valid option. +# That last point is a bit tricky.. +# +putx: btsw %dx,_MNUOPT(%bp) # Enable menu option + movw $item,%si # Display + callw putkey # key + movw %di,%si # Display the rest + +puts: callw putstr # Display string + +putn: movw $crlf,%si # To next line + +putstr: lodsb # Get byte + testb $0x80,%al # End of string? + jnz putstr.2 # Yes +putstr.1: callw putchr # Display char + jmp putstr # Continue +putstr.2: andb $~0x80,%al # Clear MSB + +putchr: pushw %dx # Save + xorw %dx,%dx # Use COM1 + xorw %cx,%cx # No timeout + movb $0x01,%ah # BIOS: Send + int $0x14 # Character + popw %dx # Restore + retw # To caller + +# One-sector disk I/O routine + +intx13: movb 0x1(%si),%dh # Load head + movw 0x2(%si),%cx # Load cylinder:sector + movb $0x1,%al # Sector count + pushw %si # Save + movw %sp,%di # Save + testb $0x80,_FLAGS(%bp) # Use packet interface? + jz intx13.1 # No + pushl $0x0 # Set the + pushl 0x8(%si) # LBA address + pushw %es # Set the transfer + pushw %bx # buffer address + push $0x1 # Block count + push $0x10 # Packet size + movw %sp,%si # Packet pointer + decw %ax # Verify off + orb $0x40,%ah # Use disk packet +intx13.1: int $0x13 # BIOS: Disk I/O + movw %di,%sp # Restore + popw %si # Restore + retw # To caller + +# Menu strings + +item: .ascii " "; .byte ' '|0x80 +prompt: .ascii "\nDef:"; .byte ' '|0x80 +crlf: .ascii "\r"; .byte '\n'|0x80 + +# Partition type tables + +tables: +# +# These entries identify invalid or NON BOOT types and partitions. +# + .byte 0x0, 0x5, 0xf +# +# These values indicate bootable types we know the names of +# + .byte 0x1, 0x4, 0x6, 0xb, 0xc, 0xe, 0x63, 0x83 + .byte 0x9f, 0xa5, 0xa6, 0xa9 +# +# These are offsets that match the known names above and point to the strings +# that will be printed. +# + .byte os_misc-. # Unknown + .byte os_dos-. # DOS + .byte os_dos-. # DOS + .byte os_dos-. # DOS + .byte os_dos-. # Windows + .byte os_dos-. # Windows + .byte os_dos-. # Windows + .byte os_unix-. # UNIX + .byte os_linux-. # Linux + .byte os_bsd-. # BSD/OS + .byte os_freebsd-. # FreeBSD + .byte os_bsd-. # OpenBSD + .byte os_bsd-. # NetBSD +# +# And here are the strings themselves. 0x80 or'd into a byte indicates +# the end of the string. (not so great for Russians but...) +# +os_misc: .ascii "?"; .byte '?'|0x80 +os_dos: .ascii "DO"; .byte 'S'|0x80 +os_unix: .ascii "UNI"; .byte 'X'|0x80 +os_linux: .ascii "Lnu"; .byte 'x'|0x80 +os_freebsd: .ascii "F" +os_bsd: .ascii "BS"; .byte 'D'|0x80 + + .org PRT_OFF-0xe,0x90 + + .word B0MAGIC # Magic number + +# +# These values are sometimes changed before writing back to the drive +# Be especially careful that nxtdrv: must come after drive:, as it +# is part of the same string. +# +drive: .ascii "Drive " +nxtdrv: .byte 0x0 # Next drive number +opt: .byte 0x0 # Option +setdrv: .byte 0x80 # Drive to force +flags: .byte FLAGS # Flags +ticks: .word TICKS # Delay + +# +# here is the 64 byte partition table that fdisk would fiddle with. +# +partbl: .fill 0x40,0x1,0x0 # Partition table + .word MAGIC # Magic number diff --git a/sys/boot/i386/boot0/boot0sio.s b/sys/boot/i386/boot0/boot0sio.s new file mode 100644 index 00000000000000..47ddfbd824dfd6 --- /dev/null +++ b/sys/boot/i386/boot0/boot0sio.s @@ -0,0 +1,437 @@ +# +# Copyright (c) 2002 Bruce M. Simpson +# Copyright (c) 1998 Robert Nordier +# All rights reserved. +# +# Redistribution and use in source and binary forms are freely +# permitted provided that the above copyright notice and this +# paragraph and the following disclaimer are duplicated in all +# such forms. +# +# This software is provided "AS IS" and without any express or +# implied warranties, including, without limitation, the implied +# warranties of merchantability and fitness for a particular +# purpose. +# + +# $FreeBSD$ + +# A 512-byte boot manager which uses a 9600 baud serial console on COM1. + + .set NHRDRV,0x475 # Number of hard drives + .set ORIGIN,0x600 # Execution address + .set FAKE,0x800 # Partition entry + .set LOAD,0x7c00 # Load address + + .set PRT_OFF,0x1be # Partition table + + .set TBL0SZ,0x3 # Table 0 size + .set TBL1SZ,0xc # Table 1 size + + .set MAGIC,0xaa55 # Magic: bootable + .set B0MAGIC,0xbb66 # Identification + + .set KEY_ENTER,0x1c # Enter key scan code + .set KEY_F1,0x3b # F1 key scan code + + .set ASCII_BEL,0x07 # ASCII code for + .set ASCII_CR,0x0D # ASCII code for + .set ASCII_1,0x31 # ASCII code for '1' + +# +# Addresses in the sector of embedded data values. +# Accessed with negative offsets from the end of the relocated sector (%ebp). +# + .set _NXTDRV,-0x48 # Next drive + .set _OPT,-0x47 # Default option + .set _SETDRV,-0x46 # Drive to force + .set _FLAGS,-0x45 # Flags + .set _TICKS,-0x44 # Timeout ticks + .set _FAKE,0x0 # Fake partition entry + .set _MNUOPT,0xc # Menu options + + .globl start # Entry point + .code16 # This runs in real mode + +# +# Initialise segments and registers to known values. +# segments start at 0. +# The stack is immediately below the address we were loaded to. +# +start: cld # String ops inc + xorw %ax,%ax # Zero + movw %ax,%es # Address + movw %ax,%ds # data + movw %ax,%ss # Set up + movw $LOAD,%sp # stack + +# +# Copy this code to the address it was linked for +# + movw %sp,%si # Source + movw $start,%di # Destination + movw $0x100,%cx # Word count + rep # Relocate + movsw # code +# +# Set address for variable space beyond code, and clear it. +# Notice that this is also used to point to the values embedded in the block, +# by using negative offsets. +# + movw %di,%bp # Address variables + movb $0x8,%cl # Words to clear + rep # Zero + stosw # them +# +# Relocate to the new copy of the code. +# + incb -0xe(%di) # Sector number + jmp main-LOAD+ORIGIN # To relocated code + +# +# Initialize the serial port. +# Must save DX (contains drive number) +# +main: pushw %dx # Save + xorw %dx,%dx # Port: COM1 + movb $0xE3,%al # 9600 8-N-1 + movb $0x00,%ah # BIOS: Set COM Port + int $0x14 # Parameters + popw %dx # Restore +# +# Check what flags were loaded with us, specifically, Use a predefined Drive. +# If what the bios gives us is bad, use the '0' in the block instead, as well. +# + testb $0x20,_FLAGS(%bp) # Set number drive? + jnz main.1 # Yes + testb %dl,%dl # Drive number valid? + js main.2 # Possibly (0x80 set) +main.1: movb _SETDRV(%bp),%dl # Drive number to use +# +# Whatever we decided to use, now store it into the fake +# partition entry that lives in the data space above us. +# +main.2: movb %dl,_FAKE(%bp) # Save drive number + callw putn # To new line + pushw %dx # Save drive number +# +# Start out with a pointer to the 4th byte of the first table entry +# so that after 4 iterations it's beyond the end of the sector. +# and beyond a 256 byte boundary and has overflowed 8 bits (see next comment). +# (remember that the table starts 2 bytes earlier than you would expect +# as the bootable flag is after it in the block) +# + movw $(partbl+0x4),%bx # Partition table (+4) + xorw %dx,%dx # Item number +# +# Loop around on the partition table, printing values until we +# pass a 256 byte boundary. The end of loop test is at main.5. +# +main.3: movb %ch,-0x4(%bx) # Zero active flag (ch == 0) + btw %dx,_FLAGS(%bp) # Entry enabled? + jnc main.5 # No +# +# If any of the entries in the table are +# the same as the 'type' in the slice table entry, +# then this is an empty or non bootable partition. Skip it. +# + movb (%bx),%al # Load type + movw $tables,%di # Lookup tables + movb $TBL0SZ,%cl # Number of entries + repne # Exclude + scasb # partition? + je main.5 # Yes +# +# Now scan the table of known types +# + movb $TBL1SZ,%cl # Number of entries + repne # Known + scasb # type? + jne main.4 # No +# +# If it matches get the matching element in the +# next array. if it doesn't, we are already +# pointing at its first element which points to a "?". +# + addw $TBL1SZ,%di # Adjust +main.4: movb (%di),%cl # Partition + addw %cx,%di # description + callw putx # Display it +main.5: incw %dx # Next item + addb $0x10,%bl # Next entry + jnc main.3 # Till done +# +# Passed a 256 byte boundary.. +# table is finished. +# Add one to the drive number and check it is valid, +# + popw %ax # Drive number + subb $0x80-0x1,%al # Does next + cmpb NHRDRV,%al # drive exist? (from BIOS?) + jb main.6 # Yes +# If not then if there is only one drive, +# Don't display drive as an option. +# + decw %ax # Already drive 0? + jz main.7 # Yes +# If it was illegal or we cycled through them, +# then go back to drive 0. +# + xorb %al,%al # Drive 0 +# +# Whatever drive we selected, make it an ascii digit and save it back +# to the "next drive" location in the loaded block in case we +# want to save it for next time. +# This also is part of the printed drive string so add 0x80 to indicate +# end of string. +# +main.6: addb $'0'|0x80,%al # Save next + movb %al,_NXTDRV(%bp) # drive number + movw $drive,%di # Display + callw putx # item +# +# Now that we've printed the drive (if we needed to), display a prompt. +# +main.7: movw $prompt,%si # Display + callw putstr # prompt + movb _OPT(%bp),%dl # Display + decw %si # default + callw putkey # key + +main.7_1: + xorb %ah,%ah # BIOS: Get + int $0x1a # system time + movw %dx,%si # Ticks when + addw _TICKS(%bp),%si # timeout + +# +# Check for a character on the serial port. +# + +main.8: xorw %dx,%dx # Use COM1 + movb $0x03,%ah # BIOS: Read COM + int $0x14 # Status + testb $0x01,%ah # Check line status + jnz main.11 # (bit 1 indicates input) + + xorb %ah,%ah # BIOS: Get + int $0x1a # system time + cmpw %si,%dx # Timeout? + jb main.8 # No + +# +# If timed out or defaulting, come here. +# +main.9: movb _OPT(%bp),%al # Load default + jmp main.12 # Join common code +# +# User's last try was bad, beep in displeasure. +# Since nothing was printed, just continue on as if the user +# hadn't done anything. This gives the effect of the user getting a beep +# for all bad keystrokes but no action until either the timeout +# occurs or the user hits a good key. +# +main.10: movb $ASCII_BEL,%al # Signal + callw putchr # error + jmp main.7_1 # Go back +# +# Check the character we just got on the serial port. +# If it's CR act as if timed out. +# +main.11: movb $0x02,%ah # BIOS: Receive + int $0x14 # COM Byte + + cmpb $ASCII_CR,%al # Enter pressed? + je main.9 # Yes +# +# Otherwise check if legal +# If not ask again. +# + subb $ASCII_1,%al # Less '1' ascii character + cmpb $0x4,%al # 1..5? + ja main.10 # No +# +# We have a selection. +# but if it's a bad selection go back to complain. +# The bits in MNUOPT were set when the options were printed. +# Anything not printed is not an option. +# +main.12: cbtw # Option + btw %ax,_MNUOPT(%bp) # enabled? + jnc main.10 # No +# +# Save the info in the original tables +# for rewriting to the disk. +# + movb %al,_OPT(%bp) # Save option + movw $FAKE,%si # Partition for write + movb (%si),%dl # Drive number + movw %si,%bx # Partition for read + cmpb $0x4,%al # 5 pressed? + pushf # Save + je main.13 # Yes + shlb $0x4,%al # Point to + addw $partbl,%ax # selected + xchgw %bx,%ax # partition + movb $0x80,(%bx) # Flag active +# +# If not asked to do a write-back (flags 0x40) don't do one. +# +main.13: pushw %bx # Save + testb $0x40,_FLAGS(%bp) # No updates? + jnz main.14 # Yes + movw $start,%bx # Data to write + movb $0x3,%ah # Write sector + callw intx13 # to disk +main.14: popw %si # Restore + popf # Restore +# +# If going to next drive, replace drive with selected one. +# Remember to un-ascii it. Hey 0x80 is already set, cool! +# + jne main.15 # If not 5 + movb _NXTDRV(%bp),%dl # Next drive + subb $'0',%dl # number XXX char val? +# +# load selected bootsector to the LOAD location in RAM. +# If it fails to read or isn't marked bootable, treat it +# as a bad selection. +# XXX what does %si carry? +# +main.15: movw $LOAD,%bx # Address for read + movb $0x2,%ah # Read sector + callw intx13 # from disk + jc main.10 # If error + cmpw $MAGIC,0x1fe(%bx) # Bootable? + jne main.10 # No + pushw %si # Save + movw $crlf,%si # Leave some + callw puts # space + popw %si # Restore + jmp *%bx # Invoke bootstrap +# +# Display routines +# + +putkey: movb $ASCII_1,%al # Prepare + addb %dl,%al # digit + jmp putstr.1 # Display the rest + +# +# Display the option and note that it is a valid option. +# That last point is a bit tricky.. +# +putx: btsw %dx,_MNUOPT(%bp) # Enable menu option + movw $item,%si # Display + callw putkey # key + movw %di,%si # Display the rest + +puts: callw putstr # Display string + +putn: movw $crlf,%si # To next line + +putstr: lodsb # Get byte + testb $0x80,%al # End of string? + jnz putstr.2 # Yes +putstr.1: callw putchr # Display char + jmp putstr # Continue +putstr.2: andb $~0x80,%al # Clear MSB + +putchr: pushw %dx # Save + xorw %dx,%dx # Use COM1 + xorw %cx,%cx # No timeout + movb $0x01,%ah # BIOS: Send + int $0x14 # Character + popw %dx # Restore + retw # To caller + +# One-sector disk I/O routine + +intx13: movb 0x1(%si),%dh # Load head + movw 0x2(%si),%cx # Load cylinder:sector + movb $0x1,%al # Sector count + pushw %si # Save + movw %sp,%di # Save + testb $0x80,_FLAGS(%bp) # Use packet interface? + jz intx13.1 # No + pushl $0x0 # Set the + pushl 0x8(%si) # LBA address + pushw %es # Set the transfer + pushw %bx # buffer address + push $0x1 # Block count + push $0x10 # Packet size + movw %sp,%si # Packet pointer + decw %ax # Verify off + orb $0x40,%ah # Use disk packet +intx13.1: int $0x13 # BIOS: Disk I/O + movw %di,%sp # Restore + popw %si # Restore + retw # To caller + +# Menu strings + +item: .ascii " "; .byte ' '|0x80 +prompt: .ascii "\nDef:"; .byte ' '|0x80 +crlf: .ascii "\r"; .byte '\n'|0x80 + +# Partition type tables + +tables: +# +# These entries identify invalid or NON BOOT types and partitions. +# + .byte 0x0, 0x5, 0xf +# +# These values indicate bootable types we know the names of +# + .byte 0x1, 0x4, 0x6, 0xb, 0xc, 0xe, 0x63, 0x83 + .byte 0x9f, 0xa5, 0xa6, 0xa9 +# +# These are offsets that match the known names above and point to the strings +# that will be printed. +# + .byte os_misc-. # Unknown + .byte os_dos-. # DOS + .byte os_dos-. # DOS + .byte os_dos-. # DOS + .byte os_dos-. # Windows + .byte os_dos-. # Windows + .byte os_dos-. # Windows + .byte os_unix-. # UNIX + .byte os_linux-. # Linux + .byte os_bsd-. # BSD/OS + .byte os_freebsd-. # FreeBSD + .byte os_bsd-. # OpenBSD + .byte os_bsd-. # NetBSD +# +# And here are the strings themselves. 0x80 or'd into a byte indicates +# the end of the string. (not so great for Russians but...) +# +os_misc: .ascii "?"; .byte '?'|0x80 +os_dos: .ascii "DO"; .byte 'S'|0x80 +os_unix: .ascii "UNI"; .byte 'X'|0x80 +os_linux: .ascii "Lnu"; .byte 'x'|0x80 +os_freebsd: .ascii "F" +os_bsd: .ascii "BS"; .byte 'D'|0x80 + + .org PRT_OFF-0xe,0x90 + + .word B0MAGIC # Magic number + +# +# These values are sometimes changed before writing back to the drive +# Be especially careful that nxtdrv: must come after drive:, as it +# is part of the same string. +# +drive: .ascii "Drive " +nxtdrv: .byte 0x0 # Next drive number +opt: .byte 0x0 # Option +setdrv: .byte 0x80 # Drive to force +flags: .byte FLAGS # Flags +ticks: .word TICKS # Delay + +# +# here is the 64 byte partition table that fdisk would fiddle with. +# +partbl: .fill 0x40,0x1,0x0 # Partition table + .word MAGIC # Magic number