WebSVN – HelenOS-historic – Diff – /kernel/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.
#
 
.section K_TEXT_START
.global kernel_image_start
 
.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,%ss			# initialize stack segment register
	movl $0x7c00,%esp		# initialize stack pointer
	
	call memmap_arch_init
	
	lgdt gdtr			# initialize Global Descriptor Table register
	lidt idtr			# initialize Interrupt Descriptor Table register
	
	movl %cr0,%eax
	orl $0x1,%eax
	movl %eax,%cr0			# switch to protected mode
	jmpl $8,$meeting_point
meeting_point:
.code32
 
	movw $16,%ax
	movw %ax,%es
	movw %ax,%gs
	movw %ax,%fs
	movw %ax,%ds			# kernel data + stack
	movw %ax,%ss
 
 
 
	call map_kernel			# map kernel and turn paging on
 
	movl $_hardcoded_ktext_size, hardcoded_ktext_size
	movl $_hardcoded_kdata_size, hardcoded_kdata_size
	movl $_hardcoded_load_address, hardcoded_load_address
 
	call main_bsp			# 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+(4096/2)), %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
 

Rev 176	Rev 177
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	.section K_TEXT_START	29	.section K_TEXT_START
30	.global kernel_image_start	30	.global kernel_image_start
31		31
32	.code16	32	.code16
33	#	33	#
34	# This is where we require any SPARTAN-kernel-compatible boot loader	34	# This is where we require any SPARTAN-kernel-compatible boot loader
35	# to pass control in real mode.	35	# to pass control in real mode.
36	#	36	#
37	# Protected mode tables are statically initialised during compile	37	# Protected mode tables are statically initialised during compile
38	# time. So we can just load the respective table registers and	38	# time. So we can just load the respective table registers and
39	# switch to protected mode.	39	# switch to protected mode.
40	#	40	#
41	kernel_image_start:	41	kernel_image_start:
42	cli	42	cli
43	xorw %ax,%ax	43	xorw %ax,%ax
44	movw %ax,%ds	44	movw %ax,%ds
45	movw %ax,%ss # initialize stack segment register	45	movw %ax,%ss # initialize stack segment register
46	movl $0x7c00,%esp # initialize stack pointer	46	movl $0x7c00,%esp # initialize stack pointer
47		47
48	call memmap_arch_init	48	call memmap_arch_init
49		49
-		50	lgdt gdtr # initialize Global Descriptor Table register
-		51	lidt idtr # initialize Interrupt Descriptor Table register
50	lgdt gdtr	52
51	movl %cr0,%eax	53	movl %cr0,%eax
52	orl $0x1,%eax	54	orl $0x1,%eax
53	movl %eax,%cr0	55	movl %eax,%cr0 # switch to protected mode
54	jmpl $8,$meeting_point	56	jmpl $8,$meeting_point
55	meeting_point:	57	meeting_point:
56	.code32	58	.code32
57		59
58	movw $16,%ax	60	movw $16,%ax
59	movw %ax,%es	61	movw %ax,%es
60	movw %ax,%gs	62	movw %ax,%gs
61	movw %ax,%fs	63	movw %ax,%fs
62	movw %ax,%ds # kernel data + stack	64	movw %ax,%ds # kernel data + stack
63	movw %ax,%ss	65	movw %ax,%ss
64		66
65	lidt idtr	-
66		-
67	call map_kernel	67	call map_kernel # map kernel and turn paging on
68		68
69	movl $_hardcoded_ktext_size, hardcoded_ktext_size	69	movl $_hardcoded_ktext_size, hardcoded_ktext_size
70	movl $_hardcoded_kdata_size, hardcoded_kdata_size	70	movl $_hardcoded_kdata_size, hardcoded_kdata_size
71	movl $_hardcoded_load_address, hardcoded_load_address	71	movl $_hardcoded_load_address, hardcoded_load_address
72		72
73	call main_bsp # never returns	73	call main_bsp # never returns
74		74
75	cli	75	cli
76	hlt	76	hlt
77		77
78	.global map_kernel	78	.global map_kernel
79	map_kernel:	79	map_kernel:
80	#	80	#
81	# Here we setup mapping for both the unmapped and mapped sections of the kernel.	81	# Here we setup mapping for both the unmapped and mapped sections of the kernel.
82	# For simplicity, we set only one 4M page for 0x00000000 and one for 0x80000000.	82	# For simplicity, we set only one 4M page for 0x00000000 and one for 0x80000000.
83	#	83	#
84	movl %cr4, %ecx	84	movl %cr4, %ecx
85	orl $(1<<4), %ecx	85	orl $(1<<4), %ecx
86	movl %ecx, %cr4 # turn PSE on	86	movl %ecx, %cr4 # turn PSE on
87		87
88	movl $((1<<7)\|(1<<0)), %eax	88	movl $((1<<7)\|(1<<0)), %eax
89	movl %eax, page_directory # mapping 0x00000000 => 0x00000000	89	movl %eax, page_directory # mapping 0x00000000 => 0x00000000
90		90
91	movl $(page_directory+(4096/2)), %edx	91	movl $(page_directory+(4096/2)), %edx
92	movl %eax, (%edx) # mapping 0x80000000 => 0x00000000	92	movl %eax, (%edx) # mapping 0x80000000 => 0x00000000
93		93
94	leal page_directory, %eax	94	leal page_directory, %eax
95	movl %eax, %cr3	95	movl %eax, %cr3
96		96
97	# turn on paging	97	# turn paging on
98	movl %cr0, %ebx	98	movl %cr0, %ebx
99	orl $(1<<31), %ebx	99	orl $(1<<31), %ebx
100	movl %ebx, %cr0	100	movl %ebx, %cr0
101	ret	101	ret
102		102
103		103
104	.section K_DATA_START	104	.section K_DATA_START
105		105
106	.align 4096	106	.align 4096
107	page_directory:	107	page_directory:
108	.space 4096, 0	108	.space 4096, 0
109		109

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/arch/ia32/src/boot/boot.S @ 1639 – Rev 176 → 177