WebSVN – HelenOS – Diff – /SPARTAN/trunk/arch/ia32/src/boot/boot.S


#
# Copyright (C) 2001-2004 Jakub Jermar
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
# - 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.
# - The name of the author may not be used to endorse or promote products
#   derived from this software without specific prior written permission.
#
# 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 AUTHOR 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.
#
 
#define __ASM__
	
#include <arch/boot/boot.h>
#include <arch/boot/memmapasm.h>
#include <arch/mm/page.h>
#include <arch/pm.h>
 
.section K_TEXT_START
.global kernel_image_start
 
KTEXT=8
KDATA=16
 
.code16
#
# This is where we require any SPARTAN-kernel-compatible boot loader
# to pass control in real mode.
#
# Protected mode tables are statically initialised during compile
# time. So we can just load the respective table registers and
# switch to protected mode.
#
kernel_image_start:
	cli
	xorw %ax, %ax
	movw %ax, %ds
	movw %ax, %es
	movw %ax, %ss							# initialize stack segment register
	movl $BOOTSTRAP_OFFSET - 0x400, %esp				# initialize stack pointer
	
	call memmap_arch_init
	
	lgdt real_bootstrap_gdtr_boot					# initialize Global Descriptor Table register
	
	movl %cr0, %eax
	orl $0x1, %eax
	movl %eax, %cr0							# switch to protected mode
	
	jmpl $KTEXT, $boot_image_start
	
.code32
.align 4
multiboot_header:
	.long MULTIBOOT_HEADER_MAGIC
	.long MULTIBOOT_HEADER_FLAGS
	.long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)	# checksum
	.long multiboot_header + BOOT_OFFSET
	.long unmapped_ktext_start + BOOT_OFFSET
	.long 0
	.long 0
	.long multiboot_image_start + BOOT_OFFSET
	
boot_image_start:
	movw $KDATA, %ax
	movw %ax, %es
	movw %ax, %gs
	movw %ax, %fs
	movw %ax, %ds							# kernel data + stack
	movw %ax, %ss
	
	movb $0xd1, %al							# enable A20 using i8042 controller
	outb %al, $0x64
	movb $0xdf, %al
	outb %al, $0x60
	
	movl $BOOTSTRAP_OFFSET, %esi
	movl $BOOTSTRAP_OFFSET + BOOT_OFFSET, %edi
	movl $_hardcoded_kernel_size, %ecx
	cld
	rep movsb
	
	call map_kernel							# map kernel and turn paging on
	
	call main_bsp							# never returns
 
	cli
	hlt
	
multiboot_image_start:
	movl $BOOTSTRAP_OFFSET - 0x400, %esp				# initialize stack pointer
	
	lgdt protected_bootstrap_gdtr - 0x80000000			# initialize Global Descriptor Table register
 
	movw $KDATA, %cx
	movw %cx, %es
	movw %cx, %gs
	movw %cx, %fs
	movw %cx, %ds							# kernel data + stack
	movw %cx, %ss
	
	jmpl $KTEXT, $multiboot_meeting_point + BOOT_OFFSET
	multiboot_meeting_point:
	
	pushl %ebx							# save parameters from GRUB
	pushl %eax
	
	movl $BOOTSTRAP_OFFSET + BOOT_OFFSET, %esi
	movl $BOOTSTRAP_OFFSET, %edi
	movl $_hardcoded_unmapped_size, %ecx
	cld
	rep movsb
	
	call map_kernel							# map kernel and turn paging on
	
	popl %eax
	popl %ebx
	cmpl $MULTIBOOT_LOADER_MAGIC, %eax				# compare GRUB signature
	je valid_boot
		
		xorl %ecx, %ecx							# no memory size or map available
		movl %ecx, e801memorysize
		movl %ecx, e820counter
		
		jmp invalid_boot
		
	valid_boot:
		
		movl (%ebx), %eax						# ebx = physical address of struct multiboot_info
		
		bt $0, %eax								# mbi->flags[0] (mem_lower, mem_upper valid)
		jc mem_valid
			
			xorl %ecx, %ecx
			jmp mem_invalid
			
		mem_valid:
		movl 4(%ebx), %ecx						# mbi->mem_lower
		addl 8(%ebx), %ecx						# mbi->mem_upper
		
		mem_invalid:
		movl %ecx, e801memorysize
		
		bt $6, %eax								# mbi->flags[6] (mmap_length, mmap_addr valid)	
		jc mmap_valid
			
			xorl %edx, %edx
			jmp mmap_invalid
			
		mmap_valid:
		movl 44(%ebx), %ecx						# mbi->mmap_length
		movl 48(%ebx), %esi						# mbi->mmap_addr
		movl $e820table, %edi
		xorl %edx, %edx
		
		mmap_loop:
			cmpl $0, %ecx
			jle mmap_end
			
			movl 4(%esi), %eax					# mmap->base_addr_low
			movl %eax, (%edi)
			
			movl 8(%esi), %eax					# mmap->base_addr_high
			movl %eax, 4(%edi)
			
			movl 12(%esi), %eax					# mmap->length_low
			movl %eax, 8(%edi)
			
			movl 16(%esi), %eax					# mmap->length_high
			movl %eax, 12(%edi)
			
			movl 20(%esi), %eax					# mmap->type
			movl %eax, 16(%edi)
			
			movl (%esi), %eax					# mmap->size
			addl $0x4, %eax
			addl %eax, %esi
			subl %eax, %ecx
			addl $MEMMAP_E820_RECORD_SIZE, %edi
			incl %edx
			jmp mmap_loop
		
		mmap_end:
		
		mmap_invalid:
		movl %edx, e820counter
		
	invalid_boot:
	
	call main_bsp - BOOT_OFFSET					# never returns
 
	cli
	hlt
 
.global map_kernel
map_kernel:
	#
	# Here we setup mapping for both the unmapped and mapped sections of the kernel.
	# For simplicity, we set only one 4M page for 0x00000000 and one for 0x80000000.
	#
	movl %cr4, %ecx
	orl $(1<<4), %ecx
	movl %ecx, %cr4							# turn PSE on
	
	movl $((1<<7)|(1<<0)), %eax
	movl %eax, page_directory					# mapping 0x00000000 => 0x00000000
 
	movl $(page_directory+2048), %edx
	movl %eax, (%edx)						# mapping 0x80000000 => 0x00000000
 
	leal page_directory, %eax
	movl %eax, %cr3
	
	# turn paging on
	movl %cr0, %ebx
	orl $(1<<31), %ebx
	movl %ebx, %cr0
	ret
 
 
.section K_DATA_START
 
.align 4096
page_directory:
	.space 4096, 0
 
.global real_bootstrap_gdtr_boot
real_bootstrap_gdtr_boot:
	.word selector(GDT_ITEMS)
	.long KA2PA(gdt)-BOOT_OFFSET
 
 

Rev 323	Rev 347
1	#	1	#
2	# Copyright (C) 2001-2004 Jakub Jermar	2	# Copyright (C) 2001-2004 Jakub Jermar
3	# All rights reserved.	3	# All rights reserved.
4	#	4	#
5	# Redistribution and use in source and binary forms, with or without	5	# Redistribution and use in source and binary forms, with or without
6	# modification, are permitted provided that the following conditions	6	# modification, are permitted provided that the following conditions
7	# are met:	7	# are met:
8	#	8	#
9	# - Redistributions of source code must retain the above copyright	9	# - Redistributions of source code must retain the above copyright
10	# notice, this list of conditions and the following disclaimer.	10	# notice, this list of conditions and the following disclaimer.
11	# - Redistributions in binary form must reproduce the above copyright	11	# - Redistributions in binary form must reproduce the above copyright
12	# notice, this list of conditions and the following disclaimer in the	12	# notice, this list of conditions and the following disclaimer in the
13	# documentation and/or other materials provided with the distribution.	13	# documentation and/or other materials provided with the distribution.
14	# - The name of the author may not be used to endorse or promote products	14	# - The name of the author may not be used to endorse or promote products
15	# derived from this software without specific prior written permission.	15	# derived from this software without specific prior written permission.
16	#	16	#
17	# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	#	27	#
28		28
29	#define __ASM__	29	#define __ASM__
30		30
31	#include <arch/boot/boot.h>	31	#include <arch/boot/boot.h>
32	#include <arch/boot/memmapasm.h>	32	#include <arch/boot/memmapasm.h>
33	#include <arch/mm/page.h>	33	#include <arch/mm/page.h>
34	#include <arch/pm.h>	34	#include <arch/pm.h>
35		35
36	.section K_TEXT_START	36	.section K_TEXT_START
37	.global kernel_image_start	37	.global kernel_image_start
38		38
39	KTEXT=8	39	KTEXT=8
40	KDATA=16	40	KDATA=16
41		41
42	.code16	42	.code16
43	#	43	#
44	# This is where we require any SPARTAN-kernel-compatible boot loader	44	# This is where we require any SPARTAN-kernel-compatible boot loader
45	# to pass control in real mode.	45	# to pass control in real mode.
46	#	46	#
47	# Protected mode tables are statically initialised during compile	47	# Protected mode tables are statically initialised during compile
48	# time. So we can just load the respective table registers and	48	# time. So we can just load the respective table registers and
49	# switch to protected mode.	49	# switch to protected mode.
50	#	50	#
51	kernel_image_start:	51	kernel_image_start:
52	cli	52	cli
53	xorw %ax, %ax	53	xorw %ax, %ax
54	movw %ax, %ds	54	movw %ax, %ds
-		55	movw %ax, %es
55	movw %ax, %ss # initialize stack segment register	56	movw %ax, %ss # initialize stack segment register
56	movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer	57	movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer
57		58
58	call memmap_arch_init	59	call memmap_arch_init
59		60
60	lgdt real_bootstrap_gdtr_boot # initialize Global Descriptor Table register	61	lgdt real_bootstrap_gdtr_boot # initialize Global Descriptor Table register
61		62
62	movl %cr0, %eax	63	movl %cr0, %eax
63	orl $0x1, %eax	64	orl $0x1, %eax
64	movl %eax, %cr0 # switch to protected mode	65	movl %eax, %cr0 # switch to protected mode
65		66
66	jmpl $KTEXT, $boot_image_start	67	jmpl $KTEXT, $boot_image_start
67		68
68	.code32	69	.code32
69	.align 4	70	.align 4
70	multiboot_header:	71	multiboot_header:
71	.long MULTIBOOT_HEADER_MAGIC	72	.long MULTIBOOT_HEADER_MAGIC
72	.long MULTIBOOT_HEADER_FLAGS	73	.long MULTIBOOT_HEADER_FLAGS
73	.long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS) # checksum	74	.long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS) # checksum
74	.long multiboot_header + BOOT_OFFSET	75	.long multiboot_header + BOOT_OFFSET
75	.long unmapped_ktext_start + BOOT_OFFSET	76	.long unmapped_ktext_start + BOOT_OFFSET
76	.long 0	77	.long 0
77	.long 0	78	.long 0
78	.long multiboot_image_start + BOOT_OFFSET	79	.long multiboot_image_start + BOOT_OFFSET
79		80
80	boot_image_start:	81	boot_image_start:
81	movw $KDATA, %ax	82	movw $KDATA, %ax
82	movw %ax, %es	83	movw %ax, %es
83	movw %ax, %gs	84	movw %ax, %gs
84	movw %ax, %fs	85	movw %ax, %fs
85	movw %ax, %ds # kernel data + stack	86	movw %ax, %ds # kernel data + stack
86	movw %ax, %ss	87	movw %ax, %ss
87		88
88	movb $0xd1, %al # enable A20 using the keyboard controller	89	movb $0xd1, %al # enable A20 using i8042 controller
89	outb %al, $0x64	90	outb %al, $0x64
90	movb $0xdf, %al	91	movb $0xdf, %al
91	outb %al, $0x60	92	outb %al, $0x60
92		93
93	movl $BOOTSTRAP_OFFSET, %esi	94	movl $BOOTSTRAP_OFFSET, %esi
94	movl $BOOTSTRAP_OFFSET + BOOT_OFFSET, %edi	95	movl $BOOTSTRAP_OFFSET + BOOT_OFFSET, %edi
95	movl $_hardcoded_kernel_size, %ecx	96	movl $_hardcoded_kernel_size, %ecx
96	cld	97	cld
97	rep movsb	98	rep movsb
98		99
99	call map_kernel # map kernel and turn paging on	100	call map_kernel # map kernel and turn paging on
100		101
101	call main_bsp # never returns	102	call main_bsp # never returns
102		103
103	cli	104	cli
104	hlt	105	hlt
105		106
106	multiboot_image_start:	107	multiboot_image_start:
107	movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer	108	movl $BOOTSTRAP_OFFSET - 0x400, %esp # initialize stack pointer
108		109
109	lgdt protected_bootstrap_gdtr - 0x80000000 # initialize Global Descriptor Table register	110	lgdt protected_bootstrap_gdtr - 0x80000000 # initialize Global Descriptor Table register
110		111
111	movw $KDATA, %cx	112	movw $KDATA, %cx
112	movw %cx, %es	113	movw %cx, %es
113	movw %cx, %gs	114	movw %cx, %gs
114	movw %cx, %fs	115	movw %cx, %fs
115	movw %cx, %ds # kernel data + stack	116	movw %cx, %ds # kernel data + stack
116	movw %cx, %ss	117	movw %cx, %ss
117		118
118	jmpl $KTEXT, $multiboot_meeting_point + BOOT_OFFSET	119	jmpl $KTEXT, $multiboot_meeting_point + BOOT_OFFSET
119	multiboot_meeting_point:	120	multiboot_meeting_point:
120		121
121	pushl %ebx # save parameters from GRUB	122	pushl %ebx # save parameters from GRUB
122	pushl %eax	123	pushl %eax
123		124
124	movl $BOOTSTRAP_OFFSET + BOOT_OFFSET, %esi	125	movl $BOOTSTRAP_OFFSET + BOOT_OFFSET, %esi
125	movl $BOOTSTRAP_OFFSET, %edi	126	movl $BOOTSTRAP_OFFSET, %edi
126	movl $_hardcoded_unmapped_size, %ecx	127	movl $_hardcoded_unmapped_size, %ecx
127	cld	128	cld
128	rep movsb	129	rep movsb
129		130
130	call map_kernel # map kernel and turn paging on	131	call map_kernel # map kernel and turn paging on
131		132
132	popl %eax	133	popl %eax
133	popl %ebx	134	popl %ebx
134	cmpl $MULTIBOOT_LOADER_MAGIC, %eax # compare GRUB signature	135	cmpl $MULTIBOOT_LOADER_MAGIC, %eax # compare GRUB signature
135	je valid_boot	136	je valid_boot
136		137
137	xorl %ecx, %ecx # no memory size or map available	138	xorl %ecx, %ecx # no memory size or map available
138	movl %ecx, e801memorysize	139	movl %ecx, e801memorysize
139	movl %ecx, e820counter	140	movl %ecx, e820counter
140		141
141	jmp invalid_boot	142	jmp invalid_boot
142		143
143	valid_boot:	144	valid_boot:
144		145
145	movl (%ebx), %eax # ebx = physical address of struct multiboot_info	146	movl (%ebx), %eax # ebx = physical address of struct multiboot_info
146		147
147	bt $0, %eax # mbi->flags[0] (mem_lower, mem_upper valid)	148	bt $0, %eax # mbi->flags[0] (mem_lower, mem_upper valid)
148	jc mem_valid	149	jc mem_valid
149		150
150	xorl %ecx, %ecx	151	xorl %ecx, %ecx
151	jmp mem_invalid	152	jmp mem_invalid
152		153
153	mem_valid:	154	mem_valid:
154	movl 4(%ebx), %ecx # mbi->mem_lower	155	movl 4(%ebx), %ecx # mbi->mem_lower
155	addl 8(%ebx), %ecx # mbi->mem_upper	156	addl 8(%ebx), %ecx # mbi->mem_upper
156		157
157	mem_invalid:	158	mem_invalid:
158	movl %ecx, e801memorysize	159	movl %ecx, e801memorysize
159		160
160	bt $6, %eax # mbi->flags[6] (mmap_length, mmap_addr valid)	161	bt $6, %eax # mbi->flags[6] (mmap_length, mmap_addr valid)
161	jc mmap_valid	162	jc mmap_valid
162		163
163	xorl %edx, %edx	164	xorl %edx, %edx
164	jmp mmap_invalid	165	jmp mmap_invalid
165		166
166	mmap_valid:	167	mmap_valid:
167	movl 44(%ebx), %ecx # mbi->mmap_length	168	movl 44(%ebx), %ecx # mbi->mmap_length
168	movl 48(%ebx), %esi # mbi->mmap_addr	169	movl 48(%ebx), %esi # mbi->mmap_addr
169	movl $e820table, %edi	170	movl $e820table, %edi
170	xorl %edx, %edx	171	xorl %edx, %edx
171		172
172	mmap_loop:	173	mmap_loop:
173	cmpl $0, %ecx	174	cmpl $0, %ecx
174	jle mmap_end	175	jle mmap_end
175		176
176	movl 4(%esi), %eax # mmap->base_addr_low	177	movl 4(%esi), %eax # mmap->base_addr_low
177	movl %eax, (%edi)	178	movl %eax, (%edi)
178		179
179	movl 8(%esi), %eax # mmap->base_addr_high	180	movl 8(%esi), %eax # mmap->base_addr_high
180	movl %eax, 4(%edi)	181	movl %eax, 4(%edi)
181		182
182	movl 12(%esi), %eax # mmap->length_low	183	movl 12(%esi), %eax # mmap->length_low
183	movl %eax, 8(%edi)	184	movl %eax, 8(%edi)
184		185
185	movl 16(%esi), %eax # mmap->length_high	186	movl 16(%esi), %eax # mmap->length_high
186	movl %eax, 12(%edi)	187	movl %eax, 12(%edi)
187		188
188	movl 20(%esi), %eax # mmap->type	189	movl 20(%esi), %eax # mmap->type
189	movl %eax, 16(%edi)	190	movl %eax, 16(%edi)
190		191
191	movl (%esi), %eax # mmap->size	192	movl (%esi), %eax # mmap->size
192	addl $0x4, %eax	193	addl $0x4, %eax
193	addl %eax, %esi	194	addl %eax, %esi
194	subl %eax, %ecx	195	subl %eax, %ecx
195	addl $MEMMAP_E820_RECORD_SIZE, %edi	196	addl $MEMMAP_E820_RECORD_SIZE, %edi
196	incl %edx	197	incl %edx
197	jmp mmap_loop	198	jmp mmap_loop
198		199
199	mmap_end:	200	mmap_end:
200		201
201	mmap_invalid:	202	mmap_invalid:
202	movl %edx, e820counter	203	movl %edx, e820counter
203		204
204	invalid_boot:	205	invalid_boot:
205		206
206	call main_bsp - BOOT_OFFSET # never returns	207	call main_bsp - BOOT_OFFSET # never returns
207		208
208	cli	209	cli
209	hlt	210	hlt
210		211
211	.global map_kernel	212	.global map_kernel
212	map_kernel:	213	map_kernel:
213	#	214	#
214	# Here we setup mapping for both the unmapped and mapped sections of the kernel.	215	# Here we setup mapping for both the unmapped and mapped sections of the kernel.
215	# For simplicity, we set only one 4M page for 0x00000000 and one for 0x80000000.	216	# For simplicity, we set only one 4M page for 0x00000000 and one for 0x80000000.
216	#	217	#
217	movl %cr4, %ecx	218	movl %cr4, %ecx
218	orl $(1<<4), %ecx	219	orl $(1<<4), %ecx
219	movl %ecx, %cr4 # turn PSE on	220	movl %ecx, %cr4 # turn PSE on
220		221
221	movl $((1<<7)\|(1<<0)), %eax	222	movl $((1<<7)\|(1<<0)), %eax
222	movl %eax, page_directory # mapping 0x00000000 => 0x00000000	223	movl %eax, page_directory # mapping 0x00000000 => 0x00000000
223		224
224	movl $(page_directory+2048), %edx	225	movl $(page_directory+2048), %edx
225	movl %eax, (%edx) # mapping 0x80000000 => 0x00000000	226	movl %eax, (%edx) # mapping 0x80000000 => 0x00000000
226		227
227	leal page_directory, %eax	228	leal page_directory, %eax
228	movl %eax, %cr3	229	movl %eax, %cr3
229		230
230	# turn paging on	231	# turn paging on
231	movl %cr0, %ebx	232	movl %cr0, %ebx
232	orl $(1<<31), %ebx	233	orl $(1<<31), %ebx
233	movl %ebx, %cr0	234	movl %ebx, %cr0
234	ret	235	ret
235		236
236		237
237	.section K_DATA_START	238	.section K_DATA_START
238		239
239	.align 4096	240	.align 4096
240	page_directory:	241	page_directory:
241	.space 4096, 0	242	.space 4096, 0
242		243
243	.global real_bootstrap_gdtr_boot	244	.global real_bootstrap_gdtr_boot
244	real_bootstrap_gdtr_boot:	245	real_bootstrap_gdtr_boot:
245	.word selector(GDT_ITEMS)	246	.word selector(GDT_ITEMS)
246	.long KA2PA(gdt)-BOOT_OFFSET	247	.long KA2PA(gdt)-BOOT_OFFSET
247		248
248		249

Subversion Repositories HelenOS

(root)/SPARTAN/trunk/arch/ia32/src/boot/boot.S – Rev 323 → 347