wok-stable rev 540

Etherboot: by the way, add DOS/COM support
author Pascal Bellard <pascal.bellard@slitaz.org>
date Thu Apr 10 22:34:56 2008 +0000 (2008-04-10)
parents 47e6882f05da
children 4a87a0aa0476
files etherboot/stuff/etherboot-prefix.u
line diff
     1.1 --- a/etherboot/stuff/etherboot-prefix.u	Fri Apr 11 02:05:05 2008 +0200
     1.2 +++ b/etherboot/stuff/etherboot-prefix.u	Thu Apr 10 22:34:56 2008 +0000
     1.3 @@ -1,6 +1,6 @@
     1.4  --- etherboot-5.4.3/src/arch/i386/prefix/liloprefix.S
     1.5  +++ etherboot-5.4.3/src/arch/i386/prefix/liloprefix.S
     1.6 -@@ -1,92 +1,361 @@
     1.7 +@@ -1,92 +1,393 @@
     1.8  -/*
     1.9  -	Copyright (C) 2000, Entity Cyber, Inc.
    1.10  -
    1.11 @@ -85,15 +85,47 @@
    1.12  -	a .lilo file is dd'ed to a floppy), print an error message. 
    1.13  -*/
    1.14  +.equ	SYSSEG, 0x1000			/* system loaded at SYSSEG<<4 */
    1.15 - 
    1.16 --bootsector: 
    1.17 --	jmp	$BOOTSEG, $go - _prefix	/* reload cs:ip to match relocation addr */
    1.18 ++
    1.19  +	.org	0
    1.20  +	.arch i386
    1.21  +	.text
    1.22  +	.section ".prefix", "ax", @progbits
    1.23  +	.code16
    1.24 + 
    1.25 +-bootsector: 
    1.26 +-	jmp	$BOOTSEG, $go - _prefix	/* reload cs:ip to match relocation addr */
    1.27 ++	call	here
    1.28 ++here:
    1.29 ++	pop	%ax
    1.30 ++	cmpw	$0x103, %ax		/* COM entry point is cs:0x100 */
    1.31 ++	jne	bootsector
    1.32 ++/* We need a real mode stack that won't be stomped on by Etherboot
    1.33 ++   which starts at 0x20000. Choose something that's sufficiently high,
    1.34 ++   but not in DOC territory. Note that we couldn't do this in a real
    1.35 ++   .com program since stack variables are in the same segment as the
    1.36 ++   code and data, but this isn't really a .com program, it just looks
    1.37 ++   like one to make DOS load it into memory. It still has the 64kB
    1.38 ++   limitation of .com files though. */
    1.39 ++#define STACK_SEG	0x7000
    1.40 ++#define STACK_SIZE	0x4000
    1.41 ++	/* Set up temporary stack */ 
    1.42 ++	movw	$STACK_SEG, %ax
    1.43 ++	movw	%ax, %ss
    1.44 ++	movw	$STACK_SIZE, %sp
    1.45  +
    1.46 ++	pushl	$0	/* No parameters to preserve for exit path */
    1.47 ++	pushw	$0	/* Dummy return address - use prefix_exit */
    1.48 ++
    1.49 ++	/* Calculate segment address of image start */
    1.50 ++	pushw	%cs
    1.51 ++	popw	%ax
    1.52 ++	addw	$(0x100/16), %ax
    1.53 ++	pushw	%ax
    1.54 ++	pushw	$_start
    1.55 ++	/* Calculated lcall to _start with %cs:0000 = image start */
    1.56 ++	lret
    1.57 ++
    1.58 ++bootsector:
    1.59  +	jmp	$BOOTSEG, $go		/* reload cs:ip to match relocation addr */
    1.60   go: 
    1.61  -	movw	$0x2000, %di		/*  0x2000 is arbitrary value >= length
    1.62 @@ -388,8 +420,8 @@
    1.63  +	movb	$4, %cl
    1.64  +	movb	$0x0e, %ah		/* write char, tty mode */
    1.65  +	movw	$0x0007, %bx		/* page 0, attribute 7 (normal) */
    1.66 -+	call	print_digit
    1.67 -+	call	print_digit
    1.68 ++	call	print_digit2
    1.69 ++print_digit2: 
    1.70  +	call	print_digit
    1.71  +/* fall through */
    1.72  +print_digit: 
    1.73 @@ -419,7 +451,7 @@
    1.74  +	.byte 36,18,15,9
    1.75   
    1.76  +msg1: 
    1.77 -+	.ascii "Loading ROM image"
    1.78 ++	.ascii "Loading ROM"
    1.79  +msg1end: 
    1.80   
    1.81   	.org	497