Clean up all of the 16-bit assembly code in the x86 bootstrap to work

with the new binutils.  Now that we have a decent assembler, all the old
m4 macros are no longer needed.  Instead, straight assembly can be used
since as(1) now understands 16-bit addressing, branches, etc.  Also,
several bugs have been fixed in as(1), allowing boot0.s to be further
cleaned up.

3 files changed, 44 insertions, 196 deletions

diff --git a/sys/boot/i386/boot0/Makefile b/sys/boot/i386/boot0/Makefile
index 5ccddf2..015a5e8 100644
--- a/sys/boot/i386/boot0/Makefile
+++ b/sys/boot/i386/boot0/Makefile
@@ -22,9 +22,9 @@ boot0: boot0.o
 	objcopy -S -O binary boot0.out ${.TARGET}
 .endif
 
-boot0.o: boot0.m4 boot0.s
-	(cd ${.CURDIR}; ${M4} -DFLAGS=${B0FLAGS} -DTICKS=${B0TICKS} \
-		boot0.m4 boot0.s) | ${AS} ${AFLAGS} -o ${.TARGET}
+boot0.o: boot0.s
+	${AS} ${AFLAGS} --defsym FLAGS=${B0FLAGS} --defsym TICKS=${B0TICKS} \
+		${.IMPSRC} -o ${.TARGET}
 
 CLEANFILES+= boot0.out boot0.o
 
diff --git a/sys/boot/i386/boot0/boot0.m4 b/sys/boot/i386/boot0/boot0.m4
deleted file mode 100644
index 7515d58..0000000
--- a/sys/boot/i386/boot0/boot0.m4
+++ /dev/null
@@ -1,77 +0,0 @@
-#
-# 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.
-#
-
-# $FreeBSD$
-
-define(_al,0x0)dnl
-define(_cl,0x1)dnl
-define(_dl,0x2)dnl
-define(_bl,0x3)dnl
-define(_ah,0x4)dnl
-define(_ch,0x5)dnl
-define(_dh,0x6)dnl
-define(_bh,0x7)dnl
-
-define(_ax,0x0)dnl
-define(_cx,0x1)dnl
-define(_dx,0x2)dnl
-define(_bx,0x3)dnl
-define(_sp,0x4)dnl
-define(_bp,0x5)dnl
-define(_si,0x6)dnl
-define(_di,0x7)dnl
-
-define(_es,0x0)dnl
-define(_cs,0x1)dnl
-define(_ss,0x2)dnl
-define(_ds,0x3)dnl
-define(_fs,0x4)dnl
-define(_gs,0x5)dnl
-
-define(_bx_si,0x0)dnl
-define(_bx_di,0x1)dnl
-define(_bp_si,0x2)dnl
-define(_bp_di,0x3)dnl
-define(_si_,0x4)dnl
-define(_di_,0x5)dnl
-define(_bp_,0x6)dnl
-define(_bx_,0x7)dnl
-
-define(o16,`.byte 0x66')dnl
-
-define(addw1r,`.byte 0x3; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
-define(addwia,`.byte 0x5; .word $1')dnl
-define(btwr1,`.word 0xa30f; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
-define(btswr1,`.word 0xab0f; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
-define(cmpbmr,`.byte 0x3a; .byte 0x6 | ($2 << 0x3); .word $1')dnl
-define(cmpw1r,`.byte 0x3b; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
-define(cmpwi2,`.byte 0x81; .byte 0xb8 | $3; .word $2; .word $1')dnl
-define(addwir,`.byte 0x83; .byte 0xc0 | $2; .byte $1')dnl
-define(movbr0,`.byte 0x88; .byte ($1 << 0x3) | $2')dnl
-define(movbr1,`.byte 0x88; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
-define(movwr1,`.byte 0x89; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
-define(movb0r,`.byte 0x8a; .byte ($2 << 0x3) | $1')dnl
-define(addb0r,`.byte 0x2; .byte ($2 << 0x3) | $1')dnl
-define(movb1r,`.byte 0x8a; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
-define(movw1r,`.byte 0x8b; .byte 0x40 | ($3 << 0x3) | $2; .byte $1')dnl
-define(movws1,`.byte 0x8c; .byte 0x40 | ($1 << 0x3) | $3; .byte $2')dnl
-define(movwir,`.byte 0xb8 | $2; .word $1')dnl
-define(movbi0,`.byte 0xc6; .byte $2; .byte $1')dnl
-define(callwi,`.byte 0xe8; .word $1 - . - 0x2')dnl
-define(jmpnwi,`.byte 0xe9; .word $1 - . - 0x2')dnl
-define(tstbi1,`.byte 0xf6; .byte 0x40 | $3; .byte $2; .byte $1')dnl
-define(incb1,`.byte 0xfe; .byte 0x40 | $2; .byte $1')dnl
-define(pushw1,`.byte 0xff; .byte 0x70 | $2; .byte $1')dnl
-define(retn,`.byte 0xc3')dnl
diff --git a/sys/boot/i386/boot0/boot0.s b/sys/boot/i386/boot0/boot0.s
index f7a3ec2..4d186ac 100644
--- a/sys/boot/i386/boot0/boot0.s
+++ b/sys/boot/i386/boot0/boot0.s
@@ -79,32 +79,23 @@ start:		cld				# String ops inc
 #
 # Relocate to the new copy of the code.
 #
-		incb1(-0xe,_di_)		# Sector number
-		/* incb $-0xe(%di) */
-		jmpnwi(main-LOAD+ORIGIN)	# To relocated code
-		/* jmp main-LOAD+ORIGIN */
+		incb -0xe(%di)			# Sector number
+		jmp main-LOAD+ORIGIN		# To relocated code
 #
 # 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.
 #
-main:		tstbi1(0x20,_FLAGS,_bp_)	# Set number drive?
-		/* testb $(0x20+_FLAGS)(%bp) */
-		.code32
+main:		testb $0x20,_FLAGS(%bp)	# Set number drive?
 		jnz main.1			# Yes
-		.code16
 		testb %dl,%dl			# Drive number valid?
-		.code32
 		js main.2			# Possibly (0x80 set)
-		.code16
-main.1: 	movb1r(_SETDRV,_bp_,_dl)	# Drive number to use
-		/* movb $_SETDRV(%bp),%dl */
+main.1: 	movb _SETDRV(%bp),%dl		# Drive number to use
 #
 # Whatever we decided to use, now store it into the fake
 # partition entry that lives in the data space above us.
 #
-main.2: 	movbr1(_dl,_FAKE,_bp_)		# Save drive number
-		/* movb %dl,$_FAKE(%bp) */
-		callwi(putn)			# To new line
+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
@@ -119,51 +110,39 @@ main.2: 	movbr1(_dl,_FAKE,_bp_)		# Save drive 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: 	movbr1(_ch,-0x4,_bx_)		# Zero active flag (ch == 0)
-	 	/* movb %ch,$-0x4(%bx) */
-		btwr1(_dx,_FLAGS,_bp_)		# Entry enabled?
-		/* bt %dx,$_FLAGS(%bp) */
-		.code32
+main.3: 	movb %ch,-0x4(%bx)		# Zero active flag (ch == 0)
+		btw %dx,_FLAGS(%bp)		# Entry enabled?
 		jnc main.5			# No
-		.code16
 #
 # 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.
 #
-		movb0r(_bx_,_al)		# Load type
-		/* movb (%bx),%al */
+		movb (%bx),%al			# Load type
 		movw $tables,%di		# Lookup tables
 		movb $TBL0SZ,%cl		# Number of entries
 		repne				# Exclude
 		scasb				#  partition?
-		.code32
 		je main.5			# Yes
-		.code16
 #
 # Now scan the table of known types
 #
 		movb $TBL1SZ,%cl		# Number of entries
 		repne				# Known
 		scasb				#  type?
-		.code32
 		jne main.4			# No
-		.code16
 #
 # 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: 	movb0r(_di_,_cl)		# Partition
-		/* movb (%di),%cl */
+main.4: 	movb (%di),%cl			# Partition
 		addw %cx,%di			#  description
-		callwi(putx)			# Display it
+		callw putx			# Display it
 main.5: 	incw %dx			# Next item 
 		addb $0x10,%bl			# Next entry
-		.code32
 		jnc main.3			# Till done
-		.code16
 #
 # Passed a 256 byte boundary..
 # table is finished.
@@ -172,16 +151,12 @@ main.5: 	incw %dx			# Next item
 		popw %ax			# Drive number
 		subb $0x80-0x1,%al		# Does next
 		cmpb NHRDRV,%al			#  drive exist? (from BIOS?)
-		.code32
 		jb main.6			# Yes
-		.code16
 # If not then if there is only one drive,
 # Don't display drive as an option.
 #
 		decw %ax			# Already drive 0?
-		.code32
 		jz main.7			# Yes
-		.code16
 # If it was illegal or we cycled through them,
 # then go back to drive 0.
 #
@@ -194,48 +169,38 @@ main.5: 	incw %dx			# Next item
 # end of string.
 #
 main.6: 	addb $'0'|0x80,%al		# Save next
-		movbr1(_al,_NXTDRV,_bp_)	#  drive number
-		/* movb %al,$NXTDRV(%bp) */
+		movb %al,_NXTDRV(%bp)		#  drive number
 		movw $drive,%di			# Display
-		callwi(putx)			#  item
+		callw putx			#  item
 #
 # Now that we've printed the drive (if we needed to), display a prompt.
 # Get ready for the input byt noting the time.
 #
 main.7: 	movw $prompt,%si		# Display
-		callwi(putstr)			#  prompt
-		movb1r(_OPT,_bp_,_dl)		# Display
-		/* movb $_OPT(%bp),%dl */
+		callw putstr			#  prompt
+		movb _OPT(%bp),%dl		# Display
 		decw %si			#  default
-		callwi(putkey)			#  key
+		callw putkey			#  key
 		xorb %ah,%ah			# BIOS: Get
 		int $0x1a			#  system time
 		movw %dx,%di			# Ticks when
-		addw1r(_TICKS,_bp_,_di) 	#  timeout
-		/* addw $_TICKS(%bp),%di */
+		addw _TICKS(%bp),%di	 	#  timeout
 # 
 # Busy loop, looking for keystrokes but
 # keeping one eye on the time.
 #
 main.8: 	movb $0x1,%ah			# BIOS: Check
 		int $0x16			#  for keypress
-		.code32
 		jnz main.11			# Have one
-		.code16
 		xorb %ah,%ah			# BIOS: Get
 		int $0x1a			#  system time
 		cmpw %di,%dx			# Timeout?
-		.code32
 		jb main.8			# No
-		.code16
 #
 # If timed out or defaulting, come here.
 #
-main.9: 	movb1r(_OPT,_bp_,_al)		# Load default
-		/* movb $_OPT(%bp),%al */
-		.code32
+main.9: 	movb _OPT(%bp),%al		# Load default
 		jmp main.12			# Join common code
-		.code16
 #
 # User's last try was bad, beep in displeasure.
 # Since nothing was printed, just continue on as if the user
@@ -244,7 +209,7 @@ main.9: 	movb1r(_OPT,_bp_,_al)		# Load default
 # occurs or the user hits a good key.
 #
 main.10:	movb $0x7,%al			# Signal
-		callwi(putchr)			#  error
+		callw putchr			#  error
 #
 # Get the keystroke.
 #
@@ -255,18 +220,14 @@ main.11:	xorb %ah,%ah			# BIOS: Get
 # If it's CR act as if timed out.
 #
 		cmpb $KEY_ENTER,%al		# Enter pressed?
-		.code32
 		je main.9			# Yes
-		.code16
 #
 # Otherwise check if legal
 # If not ask again.
 #
 		subb $KEY_F1,%al		# Less F1 scan code
 		cmpb $0x4,%al			# F1..F5?
-		.code32
 		ja main.10			# No
-		.code16
 #
 # We have a selection.
 # but if it's a bad selection go back to complain.
@@ -274,54 +235,40 @@ main.11:	xorb %ah,%ah			# BIOS: Get
 # Anything not printed is not an option.
 #
 main.12:	cbtw				# Option
-		btwr1(_ax,_MNUOPT,_bp_) 	#  enabled?
-		/* btw %ax,$_MNUOPT(%bp) */
-		.code32
+		btw %ax,_MNUOPT(%bp)	 	#  enabled?
 		jnc main.10			# No
-		.code16
 #
 # Save the info in the original tables
 # for rewriting to the disk.
 #
-		movbr1(_al,_OPT,_bp_)		# Save option
-		/* movb %al,$OPT(%bp) */
+		movb %al,_OPT(%bp)		# Save option
 		movw $FAKE,%si			# Partition for write
-		movb0r(_si_,_dl)		# Drive number
-		/* movb (%si),%dl */
+		movb (%si),%dl			# Drive number
 		movw %si,%bx			# Partition for read
 		cmpb $0x4,%al			# F5 pressed?
 		pushf				# Save
-		.code32
 		je main.13			# Yes
-		.code16
 		shlb $0x4,%al			# Point to
 		addw $partbl,%ax		#  selected
 		xchgw %bx,%ax	 		#  partition
-		movbi0(0x80,_bx_)		# Flag active
-		/* movb $0x80,(%bx) */
+		movb $0x80,(%bx)		# Flag active
 #
 # If not asked to do a write-back (flags 0x40) don't do one.
 #
 main.13:	pushw %bx			# Save
-		tstbi1(0x40,_FLAGS,_bp_)	# No updates?
-		/* testb $0x40,$_FLAGS(%bp) */
-		.code32
+		testb $0x40,_FLAGS(%bp)		# No updates?
 		jnz main.14			# Yes
-		.code16
 		movw $start,%bx			# Data to write
 		movb $0x3,%ah			# Write sector
-		callwi(intx13)			#  to disk
+		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!
 #
-		.code32
 		jne main.15			# If not F5
-		.code16
-		movb1r(_NXTDRV,_bp_,_dl)	# Next drive
-		/* movb $_NXTDRV(%bp),%dl */
+		movb _NXTDRV(%bp),%dl		# Next drive
 		subb $'0',%dl			#  number
 # 
 # load  selected bootsector to the LOAD location in RAM.
@@ -331,58 +278,43 @@ main.14:	popw %si			# Restore
 #
 main.15:	movw $LOAD,%bx			# Address for read
 		movb $0x2,%ah			# Read sector
-		callwi(intx13)			#  from disk
-		.code32
+		callw intx13			#  from disk
 		jc main.10			# If error
-		.code16
-		cmpwi2(MAGIC,0x1fe,_bx_)	# Bootable?
-		/* cmpw $MAGIC,$0x1fe(%bx) */
-		.code32
+		cmpw $MAGIC,0x1fe(%bx)		# Bootable?
 		jne main.10			# No
-		.code16
 		pushw %si			# Save
 		movw $crlf,%si			# Leave some
-		callwi(puts)			#  space
+		callw puts			#  space
 		popw %si			# Restore
-		.code32
-		jmp *%ebx			# Invoke bootstrap
-		/* jmp *%bx */
-		.code16
+		jmp *%bx			# Invoke bootstrap
 #
 # Display routines
 #
 
 putkey: 	movb $'F',%al			# Display
-		callwi(putchr)			#  'F'
+		callw putchr			#  'F'
 		movb $'1',%al			# Prepare
 		addb %dl,%al			#  digit
-		.code32
 		jmp putstr.1			# Display the rest
-		.code16
 
 #
 # Display the option and note that it is a valid option.
 # That last point is a bit tricky..
 #
-putx:		btswr1(_dx,_MNUOPT,_bp_)	# Enable menu option
-		/* btsw %dx,$_MNUOPT(%bp) */
+putx:		btsw %dx,_MNUOPT(%bp)		# Enable menu option
 		movw $item,%si			# Display
-		callwi(putkey)			#  key
+		callw putkey			#  key
 		movw %di,%si			# Display the rest
 
-puts:		callwi(putstr)			# Display string
+puts:		callw putstr			# Display string
 
 putn:		movw $crlf,%si			# To next line
 
 putstr: 	lodsb				# Get byte
 		testb $0x80,%al 		# End of string?
-		.code32
 		jnz putstr.2			# Yes
-		.code16
-putstr.1:	callwi(putchr)			# Display char
-		.code32
+putstr.1:	callw putchr			# Display char
 		jmp putstr			# Continue
-		.code16
 putstr.2:	andb $~0x80,%al 		# Clear MSB
 
 putchr: 	pushw %bx			# Save
@@ -390,26 +322,19 @@ putchr: 	pushw %bx			# Save
 		movb $0xe,%ah			# BIOS: Display
 		int $0x10			#  character
 		popw %bx			# Restore
-		retn				# To caller
+		retw				# To caller
 
 # One-sector disk I/O routine
 
-intx13: 	movb1r(0x1,_si_,_dh)		# Load head
-		/* movb $0x1(%si),%dh */
-		movw1r(0x2,_si_,_cx)		# Load cylinder:sector
-		/* movw $0x2(%si),%cx */
+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
-		tstbi1(0x80,_FLAGS,_bp_)	# Use packet interface?
-		/* testb $0x80,$_FLAGS(%bp) */
-		.code32
+		testb $0x80,_FLAGS(%bp)		# Use packet interface?
 		jz intx13.1			# No
-		.code16
 		pushl $0x0			# Set the
-		o16				#  LBA
-		pushw1(0x8,_si_)		#  address
-		/* pushl $0x8(%si) */
+		pushl 0x8(%si)			# LBA address
 		pushw %es			# Set the transfer
 		pushw %bx			#  buffer address
 		push  $0x1			# Block count
@@ -420,7 +345,7 @@ intx13: 	movb1r(0x1,_si_,_dh)		# Load head
 intx13.1:	int $0x13			# BIOS: Disk I/O
 		movw %di,%sp			# Restore
 		popw %si			# Restore
-		retn				# To caller
+		retw				# To caller
 
 # Menu strings