1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
/****************************************************************************
* arch/x86/src/i486/i486_utils.S
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Based on Bran's kernel development tutorials. Rewritten for JamesM's
* kernel development tutorials.
*
* 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.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifdef __CYGWIN__
# define SYMBOL(s) _##s
#else
# define SYMBOL(s) s
#endif
#define KSEG 0x10
/****************************************************************************
* Nasm
****************************************************************************/
#ifdef CONFIG_X86_NASM
/****************************************************************************
* Nasm externals
****************************************************************************/
global SYMBOL(gdt_flush)
global SYMBOL(idt_flush)
/****************************************************************************
* Nasm macros
****************************************************************************/
/****************************************************************************
* Nasm .text
****************************************************************************/
SECTION .text
BITS 32
/****************************************************************************
* Name: gdt_flush
****************************************************************************/
SYMBOL(gdt_flush):
mov eax, [esp+4] /* Get the pointer to the GDT, passed as a parameter */
lgdt [eax] /* Load the new GDT pointer */
mov $KSEG, ax /* KSEG is the offset in the GDT to our data segment */
mov ax, ds /* Load all data segment selectors */
mov ax, es
mov ax, fs
mov ax, gs
mov ax, ss
jmp 0x08:.gflush /* 0x08 is the offset to our code segment: Far jump! */
.gflush:
ret
/****************************************************************************
* Name: idt_flush
****************************************************************************/
SYMBOL(idt_flush):
mov eax, [esp+4] /* Get the pointer to the IDT, passed as a parameter */
lidt [eax] /* Load the IDT pointer */
ret
#else /* !CONFIG_X86_NASM (GAS) */
/****************************************************************************
* GAS
****************************************************************************/
.file "i486_utils.S"
/****************************************************************************
* GAS Globals
****************************************************************************/
.globl SYMBOL(gdt_flush)
.globl SYMBOL(idt_flush)
/****************************************************************************
* GAS .text
****************************************************************************/
.text
/****************************************************************************
* Name: gdt_flush
****************************************************************************/
#ifndef __CYGWIN__
.type SYMBOL(gdt_flush), @function
#endif
SYMBOL(gdt_flush):
movl %eax, 4(%esp) /* Get the pointer to the GDT, passed as a parameter */
lgdt (%eax) /* Load the new GDT pointer */
mov $KSEG, %ax /* KSEG is the offset in the GDT to our data segment */
mov %ax, %ds /* Load all data segment selectors */
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
mov %ax, %ss
jmp $0x08, $.Lgflush /* 0x08 is the offset to our code segment: Far jump! */
.Lgflush:
ret
#ifndef __CYGWIN__
.size SYMBOL(gdt_flush), . - SYMBOL(gdt_flush)
#endif
/****************************************************************************
* Name: idt_flush
****************************************************************************/
#ifndef __CYGWIN__
.type SYMBOL(idt_flush), @function
#endif
SYMBOL(idt_flush):
movl %eax, 4(%esp) /* Get the pointer to the IDT, passed as a parameter */
lidt (%eax) /* Load the IDT pointer */
ret
#ifndef __CYGWIN__
.size SYMBOL(idt_flush), . - SYMBOL(idt_flush)
#endif
.end
#endif /* CONFIG_X86_NASM */
|
