# HG changeset patch
# User Pascal Bellard <pascal.bellard@slitaz.org>
# Date 1335612201 -7200
# Node ID 66e38bd6a1320b7f35f2607fddd8c775fe476949
# Parent  a619433464a8b90b2bc70aba3e454832913d8c7c
linux/embedded loader: needs 256 bytes alignements, not 64k

diff -r a619433464a8 -r 66e38bd6a132 linux/stuff/linux-header.u
--- a/linux/stuff/linux-header.u	Sat Apr 28 13:11:36 2012 +0200
+++ b/linux/stuff/linux-header.u	Sat Apr 28 13:23:21 2012 +0200
@@ -1,50 +1,43 @@
---- linux-2.6.30.6/arch/x86/boot/header.S
-+++ linux-2.6.30.6/arch/x86/boot/header.S
-@@ -6,7 +6,7 @@
-  *	Based on bootsect.S and setup.S
+--- linux-3.2.14/arch/x86/boot/header.S
++++ linux-3.2.14/arch/x86/boot/header.S
+@@ -7,6 +7,7 @@
   *	modified by more people than can be counted
   *
-- *	Rewritten as a common file by H. Peter Anvin (Apr 2007)
+  *	Rewritten as a common file by H. Peter Anvin (Apr 2007)
 + *	Rewritten Pascal Bellard (Nov 2009)
   *
   * BIG FAT NOTE: We're in real mode using 64k segments.  Therefore segment
   * addresses must be multiplied by 16 to obtain their respective linear
-@@ -27,6 +27,8 @@
+@@ -27,7 +28,12 @@
  
  BOOTSEG		= 0x07C0		/* original address of boot-sector */
  SYSSEG		= 0x1000		/* historical load address >> 4 */
 +INITSEG		= 0x9000		/* boot address >> 4 */
 +SETUPSEG	= 0x9020		/* setup address >> 4 */
  
++#define LOADSEG	 0x0800
++#define LOADSZ	 (LOADSEG*0x10)
++
  #ifndef SVGA_MODE
  #define SVGA_MODE ASK_VGA
-@@ -40,53 +42,412 @@
- #define ROOT_RDONLY 1
  #endif
- 
-+/* some extra features */
-+#define	EDIT_CMDLINE		on hotkey
-+#define SHOW_REGS		show int13 status & parameters
-+
- 	.code16
- 	.section ".bstext", "ax"
+@@ -45,48 +51,366 @@
  
  	.global bootsect_start
  bootsect_start:
 +	cld				# assume nothing
 +stacktop	= 0x9E00		# in 0x8000 .. 0xA000
-+zeroed		= 48+10			# gdt + zeroed registers
++zeroed		= 48+12			# gdt + zeroed registers
 +	movw	$stacktop-12-zeroed, %di	# stacktop is an arbitrary value >=
 +					# length of bootsect + length of
 +					# setup + room for stack;
 +					# 12 is disk parm size.
 +	pushw	$INITSEG
-+	popw	%es			# %es = INITSEG
-+
-+	pushw	%es
-+	popw	%ss			# %ss and %es already contain INITSEG
++	popw	%ss			# %ss contain INITSEG
 +	movw	%di, %sp		# put stack at INITSEG:stacktop-...
-+
+ 
+-	# Normalize the start address
+-	ljmp	$BOOTSEG, $start2
 +# Many BIOS's default disk parameter tables will not recognize
 +# multi-sector reads beyond the maximum sector number specified
 +# in the default diskette parameter tables - this may mean 7
@@ -56,41 +49,61 @@
 +# count to 36 - the most we will encounter on an ED 2.88.  
 +#
 +# High doesn't hurt.  Low does.  Let's use the max: 63
-+#
-+# Segments are as follows: %es = %ss = INITSEG,
-+
+ 
+-start2:
+-	movw	%cs, %ax
+-	movw	%ax, %ds
+-	movw	%ax, %es
+-	movw	%ax, %ss
+-	xorw	%sp, %sp
+-	sti
+-	cld
++	pushw	%ss
++	popw	%es			# %es = %ss = INITSEG
 +	xorw	%ax, %ax		# %ax = 0
 +	movw	$zeroed/2, %cx		# clear gdt + offset, %ds, limits
 +	rep				# don't worry about cld
 +	stosw				# already done above
 +	popw	%bx			# offset = 0
 +	popw	%ds			# %ds = 0
-+	popw	%gs			# %gs = 0
-+
++	popw	%fs			# %fs = 0
+ 
+-	movw	$bugger_off_msg, %si
 +	movb	setup_sects+0x7C00, %al	# read bootsector + setup (%ds = 0)
 +	incw	%ax
-+
+ 
+-msg_loop:
+-	lodsb
+-	andb	%al, %al
+-	jz	bs_die
+-	movb	$0xe, %ah
+-	movw	$7, %bx
++	ldsw	0x78(%bx), %si		# %ds:%bx+0x78 is parameter table address
 +	pushw	%es
-+	pushw	%di			# %ds:%bx+0x78 is parameter table address
-+	ldsw	0x78(%bx), %si		# %ds:%si is source
++	pushw	%di
 +	movb	$6, %cl			# copy 12 bytes
 +	rep				# don't worry about cld
 +	movsw				# already done above
-+	popl	%gs:0x78(%bx)		# update parameter table address
-+	pushw	%es
++	pushw	%ss
 +	popw	%ds			# now %ds = %es = %ss = INITSEG
++	popl	%fs:0x78(%bx)		# update parameter table address
 +	movb	$63, 0x4-12(%di)	# patch sector count, %di = stacktop
 +	cli
 +
 +	xchg	%ax, %di		# sector count
 +	popw	%ax			# limits = 0
-+	incw	%cx			# cylinder 0, sector 1
++	incw	%cx			# cylinder 0, sector 1, clear Z
 +	call	read_first_sectors	# read setup
 +
-+offset_version	= 0xE
 +	movw	$0x200,%si
-+	addw	offset_version(%si),%si	# starting protocol 2.00, Kernel 1.3.73
-+	call	putstr			# show which kernel we are loading
++#define kernel_version	0xE
++type_of_loader	=	0x10
++loadflags	=	0x11
++heap_end_ptr	=	0x24
++	orw	$0x8020, type_of_loader(%si) # loader type = 0x20 = bootsect-loader
++	movb	$(stacktop-0x300)/256, heap_end_ptr+1(%si)
++	addw	kernel_version(%si),%si	# starting protocol 2.00, Kernel 1.3.73
++	call	puts			# show which kernel we are loading
 +
 +# The cmdline can be entered and modifed at boot time.
 +# Only characters before the cursor are passed to the kernel.
@@ -101,13 +114,13 @@
 +	incw	%di
 +	call	read_sectors
 +	popw	%si
-+	call	putstr
-+#ifdef	EDIT_CMDLINE
++	call	puts
 +cmdlp:
 +	movb	$0x20, %al		# clear end of line
 +	int	$0x10			#  with Space
 +	movb	$8, %al			#   and BackSpace
-+	int	$0x10
+ 	int	$0x10
+-	jmp	msg_loop
 +	decw	%si
 +cmdget:
 +	call	wait4key
@@ -116,113 +129,100 @@
 +	movb	%al, (%si)		# store char
 +	lodsw				# %si += 2
 +cmdbs:
-+#if 1
 +	cmpw	%si,cmd_line_ptr
 +	je	cmdget
-+#endif
 +	call	putc			# set %ah and %bx
 +	cmpb	$10, %al		# Enter ?
 +	jne	cmdlp
 +	movb	%bh,-2(%si)		# set end of string and remove CR
 +endcmdline:
-+#endif
 +nocmdline:
  
--	# Normalize the start address
--	ljmp	$BOOTSEG, $start2
--
--start2:
--	movw	%cs, %ax
--	movw	%ax, %ds
--	movw	%ax, %es
--	movw	%ax, %ss
--	xorw	%sp, %sp
--	sti
--	cld
--
--	movw	$bugger_off_msg, %si
-+# This routine loads the system at address SYSSEG, making sure
+-bs_die:
+-	# Allow the user to press a key, then reboot
+-	xorw	%ax, %ax
+-	int	$0x16
+-	int	$0x19
++# This routine loads the system at address LOADSEG, making sure
 +# no 64kB boundaries are crossed. We try to load it as fast as
 +# possible, loading whole tracks whenever we can.
-+
+ 
+-	# int 0x19 should never return.  In case it does anyway,
+-	# invoke the BIOS reset code...
+-	ljmp	$0xf000,$0xfff0
 +ramdisk_image	=	0x0218
 +ramdisk_size	=	0x021C
++bootsect_src_limit	= 16
++bootsect_dst_limit	= 24
++bootsect_src_base	= 18
++bootsect_dst_base	= 26
++	popw	%bx			# clear %bx
 +	movw	%sp, %si		# for bootsect_gdt
-+	decw	16(%si)			# bootsect_src = 64Kb
-+	decw	24(%si)			# bootsect_dst = 64Kb
-+	movw	$syssize, %di
-+type_of_loader	=	0x210
-+loadflags	=	0x211
-+heap_end_ptr	=	0x224
-+ksyssize	= 	500
-+	orw	$0x80FF, type_of_loader-ksyssize(%di) # loader type = 0xFF
-+	movw	$stacktop-0x200, heap_end_ptr-ksyssize(%di)
-+	movb	$0x10, %al		# destination = 0x100000
++init_gdt:
++	decw	bootsect_src_limit(%bx,%si)	# max 64Kb
++	movb	$0x93, bootsect_src_base+3(%bx,%si)
++	xorb	$bootsect_dst_limit-bootsect_src_limit, %bl
++	jne	init_gdt
++	movw	$syssize, %bx
++code32_start	=	0x214
++	movw	code32_start+1, %ax		# destination = 0x00100000 or 0x00010000
 +	movb	$5, %cl
 +initrdlp:
-+	decw	%ax
-+	movb	$0x93,%ah
-+	movw	%ax, 28(%si)		# bootsect_dst_base+2
-+	movb	$(SYSSEG/4096), %al	# source = SYSSEG
-+	movw	%ax, 20(%si)		# bootsect_src_base+2
-+	cbw
-+	cwde
-+	shlw	%cl, %ax
-+	decw	%ax
-+	addl	(%di),%eax
-+	shrl	%cl, %eax
++	movl	(%bx),%ebx
++	decl	%ebx
++	shrl	%cl, %ebx
++	incw	%bx
 +syslp:
-+	pushw	$SYSSEG
++	pushw	$LOADSEG
 +	popw	%es
-+	movw	$128,%di		# 64Kb
-+	subw	%di, %ax		# max 32M > int 15 limit
++	movw	$LOADSZ/256,%di		# size in pages
++	movw	%di, bootsect_src_base+1(%si) # assume LOADSZ == LOADSEG*16
++	movw	%ax, bootsect_dst_base+1(%si)
++	addw	%di, %ax		# next dest
++	shrw	$1, %di			# pages to sectors
++	subw	%di, %bx		# max 32M > int 15 limit
 +	pushf
 +	jnc	not_last
-+	addw	%ax, %di
++	addw	%bx, %di
 +not_last:
-+	xorw	%bx, %bx		# clear %bx
 +	pushw	%ax
-+#if defined(SHOW_REGS)
++	pushw	%di
 +	pushw	%si
-+	call	read_sectors
++	pushw	%bx
++	xorw	%bx,%bx
++	call	read_sectors		# update %bp
++	popw	%bx
 +	popw	%si
-+#else
-+	call	read_sectors
-+#endif
-+	movw	$0x8000, %cx		# full 64K
++	popw	%cx			# sectors to word count:
++	xchgb	%cl, %ch		# %cx <<= 8
 +	movb	$0x87, %ah
-+	incb	28(%si)			# bootsect_dst_base+2
++	pushw	%ss
++	popw	%es			# restore es
 +	int	$0x15			# max 16M
 +	popw	%ax
 +	popf
 +	ja	syslp
-+	movw	ramdisk_image+2,%ax
-+	movw	$ramdisk_size,%di
++	movw	ramdisk_image+1,%ax
++	movw	$ramdisk_size,%bx
 +	movb	$9, %cl
-+	cmpb	%al,28(%si)
++	cmpw	%ax, bootsect_dst_base+1(%si)
 +	jb	initrdlp
-+
+ 
+-	.section ".bsdata", "a"
+-bugger_off_msg:
+-	.ascii	"Direct booting from floppy is no longer supported.\r\n"
+-	.ascii	"Please use a boot loader program instead.\r\n"
+-	.ascii	"\n"
+-	.ascii	"Remove disk and press any key to reboot . . .\r\n"
+-	.byte	0
 +# This procedure turns off the floppy drive motor, so
 +# that we enter the kernel in a known state, and
 +# don't have to worry about it later.
+ 
++kill_motor:
++	xchgw	%ax, %di		# reset FDC (%di < 128)
++	int	$0x13
 +
-+#if 1
-+kill_motor:
-+	xchgw	%ax, %bx		# reset FDC
-+	int	$0x13
-+#else
-+kill_motor:
-+	movw	$0x3f2, %dx
-+	xchgw	%ax, %bx
-+	outb	%al, %dx
-+#endif
- 
--msg_loop:
--	lodsb
--	andb	%al, %al
--	jz	bs_die
--	movb	$0xe, %ah
--	movw	$7, %bx
 +# After that (everything loaded), we jump to the setup-routine
 +# loaded directly after the bootblock:
 +# Segments are as follows: %ds = %ss = INITSEG
@@ -240,20 +240,15 @@
 +#define FLOPPY_HEADS		2	/* 2 heads minimum */
 +#define FLOPPY_SECTORS		18	/* 18 sectors minimum */
 +
-+#ifdef SHOW_REGS
 +print_loop:
 +	movb	$0x6 + 'A' - 1, %al
 +	subb	%cl, %al
 +	movw	$regs, %si		# caller %si is saved
-+	call	putcs			# putc(%al) + putstr(%si)
++	call	putcs			# putc(%al) + puts(%si)
 +# it will print out all of the registers.
 +	popw	%bp			# load word into %si
 +	jmp	print_all		# print %bp (status)
-+#endif
 +check_limits:
-+#ifndef SHOW_REGS
-+	popw	%dx
-+#endif
 +	cmpb	$FLOPPY_SECTORS+1, %cl	# 18 sectors minimum
 +	jb	check_head
 +        cmpb    %al, %cl		# max sector known ?
@@ -265,7 +260,6 @@
 +        ja	next_cylinder		#   no -> store it
 +check_cylinder:
 +	pushaw
-+#ifdef SHOW_REGS
 +	cmpw	$0x600,%bp		# disk changed ?
 +	je	reset_floppy
 +	pushw	%es			# print %es (named EX)
@@ -290,19 +284,11 @@
 +	decb	%ch
 +	jnz	print_digit
 +	movb	$0x20, %al		# SPACE
- 	int	$0x10
--	jmp	msg_loop
--
--bs_die:
--	# Allow the user to press a key, then reboot
--	xorw	%ax, %ax
++	int	$0x10
 +	loop	print_loop
 +	call	wait
 +	cbw				# %ah = 0
 +reset_floppy:
-+#else
-+	cbw				# %ah = 0
-+#endif
 +        int     $0x13			# reset controler
 +	popaw
 +read_sectorslp:
@@ -320,38 +306,24 @@
 +	pushw	%ax			# save context
 +	movb	$2, %ah			# cmd: read chs
 +        int     $0x13
-+#ifdef SHOW_REGS
 +	xchgw	%ax, %bp		# status
-+#endif
-+# ifdef SHOW_REGS
 +	popw	%si			# save %ax
 +        popw    %ax			# limits
 +	popw	%dx
-+# else
-+	popw	%dx			# save %ax
-+        popw    %ax			# limits
-+# endif
 +	jc	check_limits
 +	xchgw	%ax, %bp
-+# ifdef SHOW_REGS
 +update_regs:
 +	incw	%cx			# next sector
-+	movw	%cx, %fs
++	movw	%cx, %gs
 +	addb	$2,%bh			# next location
 +	decw	%di			# update sector counter
 +	jz	putcdot
 +	decw	%si
 +	jnz	update_regs
-+# else
-+	addw	%dx,%cx			# next sector
-+	addb	%dl,%bh
-+	addb	%dl,%bh			# next location
-+	subw	%dx,%di			# update sector counter
-+	popw	%dx
-+	jz	putcdot
-+# endif
 +read_sectors:
-+	movw	%fs, %cx
++	movw	%gs, %cx
++#   al is last sector+1
++#   ah is last cylinder+1
 +	xchgw	%ax, %bp
 +        cmpb    %al,%cl			# reach sector limit ?
 +        jne     bdendlp
@@ -365,20 +337,17 @@
 +        movb    %dh,%ah
 +# NOTE : support 256 cylinders max
 +        incb    %ch			# next cylinder
++        cmpb    $FLOPPY_CYLINDERS, %ch	# reach cylinder limit ?
 +read_first_sectors:
 +        movb    $0,%dh			# first head
-+cylinder_count	= 496
-+        cmpb    $FLOPPY_CYLINDERS,%ch	# reach cylinder limit ?
-+        jb	bdendlp
-+	cmpb	cylinder_count, %ch
-+        jb	bdendlp
++        jne	bdendlp
 +next_floppy:
 +	movb	$0,%ch			# first cylinder
 +	pushaw
 +	movw	$swap_floppy,%si
 +	incb	12(%si)
 +	pushw	%bx
-+	call	putstr
++	call	puts
 +	popw	%bx
 +waitfloppy:
 +	call	wait
@@ -387,8 +356,6 @@
 +	cbw
 +	int	$0x13			# reset FDC
 +	movw	$0x201,%ax
-+#	cwd
-+#	movw	$1,%cx
 +	int	$0x13			# read first sector
 +	popw	%dx
 +	rclb	$1,%ah			# floppy changed 06=>0D no error 00
@@ -403,8 +370,10 @@
 +        jmp	read_sectorslp
 +
 +putcdot:
-+	pushw	%ss
-+	popw	%es			# restore es
++# REMOVE ME START
++# pushw	%ss
++# popw	%es
++# REMOVE ME STOP
 +	movb	$0x2e+3, %al 		# loading... message 2e = .
 +putclf:
 +	subb	$3, %al
@@ -416,7 +385,7 @@
 +	je	putclf
 +	ret
 +
-+putstr:
++puts:
 +	movb	$0xd, %al		# CR
 +putcs:
 +	call	putc
@@ -431,38 +400,23 @@
 +	movw	$clock, %di
 +#define DELAY 5
 +	movb	$(DELAY*182)/10,%cl
-+	addb	%gs:(%di),%cl
++	addb	%fs:(%di),%cl
 +waitkbd:
 +	movw	$0x10D, %ax		# test keyboard, timeout => CR
-+	cmpb	%gs:(%di),%cl
++	cmpb	%fs:(%di),%cl
 +	je	waitdone
- 	int	$0x16
--	int	$0x19
++	int	$0x16
 +	jz	waitkbd
 +	cbw
 +	int	$0x16			# eat char
-+	movw	%di, %gs		# disable timeout
++	movw	%di, %fs		# disable timeout
 +	incw	%di			# clear Z
 +waitdone:
 +	ret
- 
--	# int 0x19 should never return.  In case it does anyway,
--	# invoke the BIOS reset code...
--	ljmp	$0xf000,$0xfff0
--
--	.section ".bsdata", "a"
--bugger_off_msg:
--	.ascii	"Direct booting from floppy is no longer supported.\r\n"
--	.ascii	"Please use a boot loader program instead.\r\n"
--	.ascii	"\n"
--	.ascii	"Remove disk and press any key to reboot . . .\r\n"
--	.byte	0
-+#ifdef SHOW_REGS
-+regs:		.asciz	"X:"
-+#endif
- 
++
++regs:	.asciz	"X:"
++
 +swap_floppy:	.ascii	"Insert disk 1"
-+		.ascii	"."
 +		.byte	7,13,0
  
  	# Kernel attributes; used by setup.  This is part 1 of the