first shot of legacybios emulation.

does not work yet.. sorry :-(


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1119 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

util/extensions/legacybios/arch/x86/mboot.S

@@ -0,0 +1,57 @@
+/* mboot.S 
+ * legacybios assembler bootstrap for multiboot
+ *
+ * Copyright (C) 2003 Stefan Reinauer
+ *
+ * See the file "COPYING" for further information about
+ * the copyright and warranty status of this work.
+ */
+
+#define ASM 1
+#include <multiboot.h>
+	
+	.text
+
+	.code32
+	.globl	start, _start
+
+	/* unused */
+start:
+_start:
+	jmp	multiboot_entry
+
+	/* Align 32 bits boundary.  */
+	.align	4
+	
+	/* Multiboot header.  */
+multiboot_header:
+	.long	MULTIBOOT_HEADER_MAGIC /* magic */
+	.long	MULTIBOOT_HEADER_FLAGS /* flags */
+	.long	-(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS) 
+	        /* checksum */
+	.long	multiboot_header /* header_addr */
+	.long	_start /* load_addr */
+	.long	_edata /* load_end_addr */
+	.long	_end /* bss_end_addr */
+	.long	multiboot_entry /* entry_addr */
+
+multiboot_entry:
+	/* Initialize stack pointer.  */
+	movl	$(stack + STACK_SIZE), %esp
+
+	/* Reset EFLAGS.  */
+	pushl	$0
+	popf
+
+	/* pointer to multiboot information structure.  */
+	pushl	%ebx
+	/* magic value.  */
+	pushl	%eax
+
+	/* jump to C main function...  */
+	call	EXT_C(cmain)
+
+loop:	hlt
+	jmp	loop
+
+	.comm	stack, STACK_SIZE /* stack area.  */