source: mainline/arch/ia32/src/boot/boot.S@ 20d50a1

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 20d50a1 was 66def8d, checked in by Martin Decky <martin@…>, 20 years ago

simplify and cleanup ia32 boot process, remove obsolete stuff
  • Property mode set to 100644
File size: 5.4 KB
Line 
1#
2# Copyright (C) 2001-2004 Jakub Jermar
3# Copyright (C) 2005-2006 Martin Decky
4# All rights reserved.
5#
6# Redistribution and use in source and binary forms, with or without
7# modification, are permitted provided that the following conditions
8# are met:
9#
10# - Redistributions of source code must retain the above copyright
11# notice, this list of conditions and the following disclaimer.
12# - Redistributions in binary form must reproduce the above copyright
13# notice, this list of conditions and the following disclaimer in the
14# documentation and/or other materials provided with the distribution.
15# - The name of the author may not be used to endorse or promote products
16# derived from this software without specific prior written permission.
17#
18# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28#
29
30#include <arch/boot/boot.h>
31#include <arch/boot/memmap.h>
32#include <arch/mm/page.h>
33#include <arch/pm.h>
34
35#define START_STACK (BOOT_OFFSET - BOOT_STACK_SIZE)
36
37.section K_TEXT_START, "ax"
38
39KTEXT=8
40KDATA=16
41
42.code32
43.align 4
44.global multiboot_image_start
45multiboot_header:
46 .long MULTIBOOT_HEADER_MAGIC
47 .long MULTIBOOT_HEADER_FLAGS
48 .long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS) # checksum
49 .long multiboot_header
50 .long unmapped_ktext_start
51 .long 0
52 .long 0
53 .long multiboot_image_start
54
55multiboot_image_start:
56 movl $START_STACK, %esp # initialize stack pointer
57 lgdt KA2PA(bootstrap_gdtr) # initialize Global Descriptor Table register
58
59 movw $KDATA, %cx
60 movw %cx, %es
61 movw %cx, %gs
62 movw %cx, %fs
63 movw %cx, %ds # kernel data + stack
64 movw %cx, %ss
65
66 jmpl $KTEXT, $multiboot_meeting_point
67 multiboot_meeting_point:
68
69 pushl %ebx # save parameters from GRUB
70 pushl %eax
71
72 call map_kernel # map kernel and turn paging on
73
74 popl %eax
75 popl %ebx
76 cmpl $MULTIBOOT_LOADER_MAGIC, %eax # compare GRUB signature
77 je valid_boot
78
79 xorl %ecx, %ecx # no memory size or map available
80 movl %ecx, e801memorysize
81 movl %ecx, e820counter
82
83 jmp invalid_boot
84
85 valid_boot:
86
87 movl (%ebx), %eax # ebx = physical address of struct multiboot_info
88
89 bt $0, %eax # mbi->flags[0] (mem_lower, mem_upper valid)
90 jc mem_valid
91
92 xorl %ecx, %ecx
93 jmp mem_invalid
94
95 mem_valid:
96 movl 4(%ebx), %ecx # mbi->mem_lower
97 addl 8(%ebx), %ecx # mbi->mem_upper
98
99 mem_invalid:
100 movl %ecx, e801memorysize
101
102 bt $3, %eax # mbi->flags[3] (mods_count, mods_addr valid)
103 jc mods_valid
104
105 xorl %ecx, %ecx
106 xorl %edx, %edx
107 jmp mods_invalid
108
109 mods_valid:
110 movl 20(%ebx), %ecx # mbi->mods_count
111 cmpl $0, %ecx
112 je mods_invalid
113
114 movl 24(%ebx), %esi # mbi->mods_addr
115 movl 0(%esi), %edx # mods->mod_start
116 movl 4(%esi), %ecx # mods->mod_end
117 subl %edx, %ecx
118 addl $0x80000000, %edx
119
120 mods_invalid:
121 movl %ecx, init_size
122 movl %edx, init_addr
123
124 bt $6, %eax # mbi->flags[6] (mmap_length, mmap_addr valid)
125 jc mmap_valid
126
127 xorl %edx, %edx
128 jmp mmap_invalid
129
130 mmap_valid:
131 movl 44(%ebx), %ecx # mbi->mmap_length
132 movl 48(%ebx), %esi # mbi->mmap_addr
133 movl $e820table, %edi
134 xorl %edx, %edx
135
136 mmap_loop:
137 cmpl $0, %ecx
138 jle mmap_end
139
140 movl 4(%esi), %eax # mmap->base_addr_low
141 movl %eax, (%edi)
142
143 movl 8(%esi), %eax # mmap->base_addr_high
144 movl %eax, 4(%edi)
145
146 movl 12(%esi), %eax # mmap->length_low
147 movl %eax, 8(%edi)
148
149 movl 16(%esi), %eax # mmap->length_high
150 movl %eax, 12(%edi)
151
152 movl 20(%esi), %eax # mmap->type
153 movl %eax, 16(%edi)
154
155 movl (%esi), %eax # mmap->size
156 addl $0x4, %eax
157 addl %eax, %esi
158 subl %eax, %ecx
159 addl $MEMMAP_E820_RECORD_SIZE, %edi
160 incl %edx
161 jmp mmap_loop
162
163 mmap_end:
164
165 mmap_invalid:
166 movl %edx, e820counter
167
168 invalid_boot:
169
170#ifdef CONFIG_SMP
171
172 # copy AP bootstrap routines below 1 MB
173
174 movl $BOOT_OFFSET, %esi
175 movl $AP_BOOT_OFFSET, %edi
176 movl $_hardcoded_unmapped_size, %ecx
177 cld
178 rep movsb
179
180#endif
181
182 call main_bsp # never returns
183
184 cli
185 hlt
186
187.global map_kernel
188map_kernel:
189 #
190 # Here we setup mapping for both the unmapped and mapped sections of the kernel.
191 # For simplicity, we map the entire 4G space.
192 #
193 movl %cr4, %ecx
194 orl $(1<<4), %ecx
195 movl %ecx, %cr4 # turn PSE on
196
197 movl $(page_directory+0), %esi
198 movl $(page_directory+2048), %edi
199 xorl %ecx, %ecx
200 xorl %ebx, %ebx
2010:
202 movl $((1<<7)|(1<<0)), %eax
203 orl %ebx, %eax
204 movl %eax, (%esi,%ecx,4) # mapping 0x00000000+%ecx*4M => 0x00000000+%ecx*4M
205 movl %eax, (%edi,%ecx,4) # mapping 0x80000000+%ecx*4M => 0x00000000+%ecx*4M
206 addl $(4*1024*1024), %ebx
207
208 incl %ecx
209 cmpl $512, %ecx
210 jl 0b
211
212 movl %esi, %cr3
213
214 # turn paging on
215 movl %cr0, %ebx
216 orl $(1<<31), %ebx
217 movl %ebx, %cr0
218 ret
219
220
221.section K_DATA_START, "aw", @progbits
222
223.align 4096
224page_directory:
225 .space 4096, 0
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