xref: /netbsd/sys/arch/i386/i386/bioscall.S (revision d30037bb)
1/*	$NetBSD: bioscall.S,v 1.11 2023/02/25 13:52:09 riastradh Exp $ */
2
3/*-
4 * Copyright (c) 1997 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by John Kohl.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <machine/asm.h>
33__KERNEL_RCSID(0, "$NetBSD: bioscall.S,v 1.11 2023/02/25 13:52:09 riastradh Exp $");
34
35#include <machine/bioscall.h>
36
37#include "assym.h"
38
39/* LINTSTUB: include <sys/types.h> */
40/* LINTSTUB: include <machine/bioscall.h> */
41
42	.section ".rodata"
43_C_LABEL(biostramp_image):
44	.globl	_C_LABEL(biostramp_image)
45
468:
47#include "i386/bioscall/biostramp.inc"
489:
49
50	.globl	_C_LABEL(biostramp_image_size)
51_C_LABEL(biostramp_image_size):
52	.long	9b - 8b
53
54	.text
55/*
56 * void bioscall(int function, struct bioscallregs *regs):
57 * 	call the BIOS interrupt "function" from real mode with
58 *	registers as specified in "regs"
59 *	for the flags, though, only these flags are passed to the BIOS--
60 *	the remainder come from the flags register at the time of the call:
61 *	(PSL_C|PSL_PF|PSL_AF|PSL_Z|PSL_N|PSL_D|PSL_V)
62 *
63 *	Fills in *regs with registers as returned by BIOS.
64 */
65/* LINTSTUB: Func: void bioscall(int function, struct bioscallregs *regs) */
66ENTRY(bioscall)
67	pushl	%ebp
68	movl	%esp,%ebp		/* set up frame ptr */
69
70	call	_C_LABEL(kpreempt_disable)
71
72	/* install lwp0 pmap */
73	movl	_C_LABEL(kernel_pmap_ptr),%eax
74	pushl	%eax
75	call	_C_LABEL(cpu_load_pmap)
76	addl	$4,%esp
77
78	movl	$(BIOSTRAMP_BASE),%eax	/* address of trampoline area */
79	pushl	12(%ebp)
80	pushl	8(%ebp)
81	call	*%eax			/* machdep.c initializes it */
82	addl	$8,%esp			/* clear args from stack */
83
84	/* restore pmap - saved value is in curcpu()->ci_pmap */
85	movl	%fs:(CPU_INFO_PMAP),%eax
86	pushl	%eax
87	call	_C_LABEL(cpu_load_pmap)
88	addl	$4,%esp
89
90	call	_C_LABEL(kpreempt_enable)
91
92	leave
93	ret
94