diff options
Diffstat (limited to 'sys/arch/amd64/stand/boot/srt0.S')
| -rw-r--r-- | sys/arch/amd64/stand/boot/srt0.S | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/sys/arch/amd64/stand/boot/srt0.S b/sys/arch/amd64/stand/boot/srt0.S new file mode 100644 index 00000000000..ccd3eff0ed2 --- /dev/null +++ b/sys/arch/amd64/stand/boot/srt0.S @@ -0,0 +1,92 @@ +/* $OpenBSD: srt0.S,v 1.1 2004/02/03 12:09:47 mickey Exp $ */ + +/* + * Copyright (c) 1997 Michael Shalayeff + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + */ +#include <machine/asm.h> +#include <assym.h> + +#define BOOTSTACK 0xfffc + + .globl _C_LABEL(end) + .globl _C_LABEL(edata) + .globl _C_LABEL(boot) + .globl _C_LABEL(_rtt) + .globl _C_LABEL(bios_bootdev) + .globl _ASM_LABEL(pmm_init) + .globl Gdtr + + .text + .code16 + .globl _start +_start: + popl %eax + cmpl $BOOTMAGIC, %eax + je 1f +#ifdef DEBUG + movl $0xb80a0, %ebx + addr32 movl $0x07420742, (%ebx) +#endif +1: + popl %edx + cli + pushl %cs + popl %ds + addr32 data32 lgdt (Gdtr - LINKADDR) + movl %cr0, %eax + orl $CR0_PE, %eax + data32 movl %eax, %cr0 + data32 ljmp $8, $1f +1: + .code32 + movl $0x10,%eax + mov %ax,%ds + mov %ax,%ss + mov %ax,%es + mov %ax,%fs + mov %ax,%gs + movl $BOOTSTACK,%esp + pushl %edx + movl %edx, _C_LABEL(bios_bootdev) + + /* Now do it all */ + call _ASM_LABEL(pmm_init) +#ifdef DEBUG + movl $0xb80a4, %ebx + movl $0x07520752, (%ebx) +#endif + /* zero .bss */ + xorl %eax, %eax + movl $_C_LABEL(end), %ecx + subl $_C_LABEL(edata),%ecx + movl $_C_LABEL(edata), %edi + cld + rep; stosb + + call _C_LABEL(boot) + + jmp _C_LABEL(_rtt) + |