diff --git a/src/arch/i386/prefix/boot1a.s b/src/arch/i386/prefix/boot1a.s deleted file mode 100644 index 557462f1..00000000 --- a/src/arch/i386/prefix/boot1a.s +++ /dev/null @@ -1,410 +0,0 @@ -# This code is no longer used in Etherboot. It is not maintained and -# may not work. - - -# -# Copyright (c) 1998 Robert Nordier -# All rights reserved. -# Very small bootrom changes by Luigi Rizzo -# -# I recently had the problem of downloading the etherboot code -# from a hard disk partition instead of a floppy, and noticed that -# floppyload.S does not do the job. With a bit of hacking to -# the FreeBSD's boot1.s code, I managed to obtain a boot sector -# which works both for floppies and hard disks -- basically you -# do something like -# -# cat boot1a bin32/.lzrom > /dev/ad0s4 -# -# (or whatever is the HD partition you are using, I am using slice -# 4 on FreeBSD) and you are up and running. -# Then with "fdisk" you have to mark your partition as having type "1" -# (which is listed as DOS-- but basically it must be something matching -# the variable PRT_BSD in the assembly source below). -# -# -# 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. -# -# Makefile: -#boot1a: boot1a.out -# objcopy -S -O binary boot1a.out boot1a -# -#boot1a.out: boot1a.o -# ld -nostdlib -static -N -e start -Ttext 0x7c00 -o boot1a.out boot1a.o -# -#boot1a.o: boot1a.s -# as --defsym FLAGS=0x80 boot1a.s -o boot1a.o -# -# - -# $FreeBSD: src/sys/boot/i386/boot2/boot1.s,v 1.10.2.2 2000/07/07 21:12:32 jhb Exp $ - -# Memory Locations - .set MEM_REL,0x700 # Relocation address - .set MEM_ARG,0x900 # Arguments - .set MEM_ORG,0x7c00 # Origin - .set MEM_BUF,0x8c00 # Load area - .set MEM_BTX,0x9000 # BTX start - .set MEM_JMP,0x9010 # BTX entry point - .set MEM_USR,0xa000 # Client start - .set BDA_BOOT,0x472 # Boot howto flag - -# Partition Constants - .set PRT_OFF,0x1be # Partition offset - .set PRT_NUM,0x4 # Partitions - .set PRT_BSD,0x1 # Partition type - -# Flag Bits - .set FL_PACKET,0x80 # Packet mode - -# Misc. Constants - .set SIZ_PAG,0x1000 # Page size - .set SIZ_SEC,0x200 # Sector size - - .globl start - .globl xread - .code16 - -start: jmp main # Start recognizably - - .org 0x4,0x90 -# -# Trampoline used by boot2 to call read to read data from the disk via -# the BIOS. Call with: -# -# %cx:%ax - long - LBA to read in -# %es:(%bx) - caddr_t - buffer to read data into -# %dl - byte - drive to read from -# %dh - byte - num sectors to read -# - -xread: push %ss # Address - pop %ds # data -# -# Setup an EDD disk packet and pass it to read -# -xread.1: # Starting - pushl $0x0 # absolute - push %cx # block - push %ax # number - push %es # Address of - push %bx # transfer buffer - xor %ax,%ax # Number of - movb %dh,%al # blocks to - push %ax # transfer - push $0x10 # Size of packet - mov %sp,%bp # Packet pointer - callw read # Read from disk - lea 0x10(%bp),%sp # Clear stack - lret # To far caller -# -# Load the rest of boot2 and BTX up, copy the parts to the right locations, -# and start it all up. -# - -# -# Setup the segment registers to flat addressing (segment 0) and setup the -# stack to end just below the start of our code. -# -main: cld # String ops inc - xor %cx,%cx # Zero - mov %cx,%es # Address - mov %cx,%ds # data - mov %cx,%ss # Set up - mov $start,%sp # stack -# -# Relocate ourself to MEM_REL. Since %cx == 0, the inc %ch sets -# %cx == 0x100. -# - mov %sp,%si # Source - mov $MEM_REL,%di # Destination - incb %ch # Word count - rep # Copy - movsw # code -# -# If we are on a hard drive, then load the MBR and look for the first -# FreeBSD slice. We use the fake partition entry below that points to -# the MBR when we call nread. The first pass looks for the first active -# FreeBSD slice. The second pass looks for the first non-active FreeBSD -# slice if the first one fails. -# - mov $part4,%si # Partition - cmpb $0x80,%dl # Hard drive? - jb main.4 # No - movb $0x1,%dh # Block count - callw nread # Read MBR - mov $0x1,%cx # Two passes -main.1: mov $MEM_BUF+PRT_OFF,%si # Partition table - movb $0x1,%dh # Partition -main.2: cmpb $PRT_BSD,0x4(%si) # Our partition type? - jne main.3 # No - jcxz main.5 # If second pass - testb $0x80,(%si) # Active? - jnz main.5 # Yes -main.3: add $0x10,%si # Next entry - incb %dh # Partition - cmpb $0x1+PRT_NUM,%dh # In table? - jb main.2 # Yes - dec %cx # Do two - jcxz main.1 # passes -# -# If we get here, we didn't find any FreeBSD slices at all, so print an -# error message and die. -# -booterror: mov $msg_part,%si # Message - jmp error # Error -# -# Floppies use partition 0 of drive 0. -# -main.4: xor %dx,%dx # Partition:drive -# -# Ok, we have a slice and drive in %dx now, so use that to locate and load -# boot2. %si references the start of the slice we are looking for, so go -# ahead and load up the first 16 sectors (boot1 + boot2) from that. When -# we read it in, we conveniently use 0x8c00 as our transfer buffer. Thus, -# boot1 ends up at 0x8c00, and boot2 starts at 0x8c00 + 0x200 = 0x8e00. -# The first part of boot2 is the disklabel, which is 0x200 bytes long. -# The second part is BTX, which is thus loaded into 0x9000, which is where -# it also runs from. The boot2.bin binary starts right after the end of -# BTX, so we have to figure out where the start of it is and then move the -# binary to 0xb000. Normally, BTX clients start at MEM_USR, or 0xa000, but -# when we use btxld create boot2, we use an entry point of 0x1000. That -# entry point is relative to MEM_USR; thus boot2.bin starts at 0xb000. -# -main.5: mov %dx,MEM_ARG # Save args - movb $0x2,%dh # Sector count - mov $0x7e00, %bx - callw nreadbx # Read disk - movb $0x40,%dh # Sector count - movb %dh, %al - callw puthex - mov $0x7e00, %bx - callw nreadbx # Read disk - push %si - mov $msg_r1,%si - callw putstr - pop %si - lcall $0x800,$0 # enter the rom code - int $0x19 - -msg_r1: .asciz " done\r\n" - -.if 0 - mov $MEM_BTX,%bx # BTX - mov 0xa(%bx),%si # Get BTX length and set - add %bx,%si # %si to start of boot2.bin - mov $MEM_USR+SIZ_PAG,%di # Client page 1 - mov $MEM_BTX+0xe*SIZ_SEC,%cx # Byte - sub %si,%cx # count - rep # Relocate - movsb # client - sub %di,%cx # Byte count - xorb %al,%al # Zero assumed bss from - rep # the end of boot2.bin - stosb # up to 0x10000 - callw seta20 # Enable A20 - jmp start+MEM_JMP-MEM_ORG # Start BTX -# -# Enable A20 so we can access memory above 1 meg. -# -seta20: cli # Disable interrupts -seta20.1: inb $0x64,%al # Get status - testb $0x2,%al # Busy? - jnz seta20.1 # Yes - movb $0xd1,%al # Command: Write - outb %al,$0x64 # output port -seta20.2: inb $0x64,%al # Get status - testb $0x2,%al # Busy? - jnz seta20.2 # Yes - movb $0xdf,%al # Enable - outb %al,$0x60 # A20 - sti # Enable interrupts - retw # To caller -.endif -# -# Trampoline used to call read from within boot1. -# -nread: mov $MEM_BUF,%bx # Transfer buffer -nreadbx: # same but address is in bx - mov 0x8(%si),%ax # Get - mov 0xa(%si),%cx # LBA - push %bx - push %ax - callw putword - pop %ax - pop %bx - push %cs # Read from - callw xread.1 # disk - jnc return # If success, return - mov $msg_read,%si # Otherwise, set the error - # message and fall through to - # the error routine -# -# Print out the error message pointed to by %ds:(%si) followed -# by a prompt, wait for a keypress, and then reboot the machine. -# -error: callw putstr # Display message - mov $prompt,%si # Display - callw putstr # prompt - xorb %ah,%ah # BIOS: Get - int $0x16 # keypress - movw $0x1234, BDA_BOOT # Do a warm boot - ljmp $0xffff,$0x0 # reboot the machine -# -# Display a null-terminated string using the BIOS output. -# -putstr.0: call putchar -putstr: lodsb # Get char - testb %al,%al # End of string? - jne putstr.0 # No - retw - -putword: push %ax - movb $'.', %al - callw putchar - movb %ah, %al - callw puthex - pop %ax -puthex: push %ax - shr $4, %al - callw putdigit - pop %ax -putdigit: - andb $0xf, %al - addb $0x30, %al - cmpb $0x39, %al - jbe putchar - addb $7, %al -putchar: push %ax - mov $0x7,%bx - movb $0xe,%ah - int $0x10 - pop %ax - retw - -# -# Overused return code. ereturn is used to return an error from the -# read function. Since we assume putstr succeeds, we (ab)use the -# same code when we return from putstr. -# -ereturn: movb $0x1,%ah # Invalid - stc # argument -return: retw # To caller -# -# Reads sectors from the disk. If EDD is enabled, then check if it is -# installed and use it if it is. If it is not installed or not enabled, then -# fall back to using CHS. Since we use a LBA, if we are using CHS, we have to -# fetch the drive parameters from the BIOS and divide it out ourselves. -# Call with: -# -# %dl - byte - drive number -# stack - 10 bytes - EDD Packet -# -read: push %dx # Save - movb $0x8,%ah # BIOS: Get drive - int $0x13 # parameters - movb %dh,%ch # Max head number - pop %dx # Restore - jc return # If error - andb $0x3f,%cl # Sectors per track - jz ereturn # If zero - cli # Disable interrupts - mov 0x8(%bp),%eax # Get LBA - push %dx # Save - movzbl %cl,%ebx # Divide by - xor %edx,%edx # sectors - div %ebx # per track - movb %ch,%bl # Max head number - movb %dl,%ch # Sector number - inc %bx # Divide by - xorb %dl,%dl # number - div %ebx # of heads - movb %dl,%bh # Head number - pop %dx # Restore - cmpl $0x3ff,%eax # Cylinder number supportable? - sti # Enable interrupts - ja read.7 # No, try EDD - xchgb %al,%ah # Set up cylinder - rorb $0x2,%al # number - orb %ch,%al # Merge - inc %ax # sector - xchg %ax,%cx # number - movb %bh,%dh # Head number - subb %ah,%al # Sectors this track - mov 0x2(%bp),%ah # Blocks to read - cmpb %ah,%al # To read - jb read.2 # this - movb %ah,%al # track -read.2: mov $0x5,%di # Try count -read.3: les 0x4(%bp),%bx # Transfer buffer - push %ax # Save - movb $0x2,%ah # BIOS: Read - int $0x13 # from disk - pop %bx # Restore - jnc read.4 # If success - dec %di # Retry? - jz read.6 # No - xorb %ah,%ah # BIOS: Reset - int $0x13 # disk system - xchg %bx,%ax # Block count - jmp read.3 # Continue -read.4: movzbw %bl,%ax # Sectors read - add %ax,0x8(%bp) # Adjust - jnc read.5 # LBA, - incw 0xa(%bp) # transfer -read.5: shlb %bl # buffer - add %bl,0x5(%bp) # pointer, - sub %al,0x2(%bp) # block count - ja read # If not done -read.6: retw # To caller -read.7: testb $FL_PACKET,%cs:MEM_REL+flags-start # LBA support enabled? - jz ereturn # No, so return an error - mov $0x55aa,%bx # Magic - push %dx # Save - movb $0x41,%ah # BIOS: Check - int $0x13 # extensions present - pop %dx # Restore - jc return # If error, return an error - cmp $0xaa55,%bx # Magic? - jne ereturn # No, so return an error - testb $0x1,%cl # Packet interface? - jz ereturn # No, so return an error - mov %bp,%si # Disk packet - movb $0x42,%ah # BIOS: Extended - int $0x13 # read - retw # To caller - -# Messages - -msg_read: .asciz "Rd" -msg_part: .asciz "Boot" - -prompt: .asciz " err\r\n" - -flags: .byte FLAGS # Flags - - .org PRT_OFF,0x90 - -# Partition table - - .fill 0x30,0x1,0x0 -part4: .byte 0x80 - .byte 0x00 # start head - .byte 0x01 # start sector (6 bits) + start cyl (2 bit) - .byte 0x00 # start cyl (low 8 bits) - .byte 0x1 # part.type - .byte 0xff # end head - .byte 0xff # end sect (6) + end_cyl(2) - .byte 0xff # end cyl - .byte 0x00, 0x00, 0x00, 0x00 # explicit start - .byte 0x50, 0xc3, 0x00, 0x00 # 50000 sectors long, bleh - - .word 0xaa55 # Magic number