Subversion Repositories HelenOS-historic

Rev

Rev 843 | Rev 934 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
160 jermar 1
#
2
# Copyright (C) 2005 Jakub Jermar
3
# All rights reserved.
4
#
5
# Redistribution and use in source and binary forms, with or without
6
# modification, are permitted provided that the following conditions
7
# are met:
8
#
9
# - Redistributions of source code must retain the above copyright
10
#   notice, this list of conditions and the following disclaimer.
11
# - Redistributions in binary form must reproduce the above copyright
12
#   notice, this list of conditions and the following disclaimer in the
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
15
#   derived from this software without specific prior written permission.
16
#
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
19
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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
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
26
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
#
28
 
845 decky 29
#include <arch/asm/regname.h>
843 palkovsky 30
#include <arch/asm/spr.h>
191 decky 31
 
160 jermar 32
.section K_TEXT_START
33
 
34
.global kernel_image_start
35
 
843 palkovsky 36
.org 0x0
37
/* 256 bytes of some data */
38
/* exception table - must use 'ba' instructions for branches,
39
 * because it is elsewhere than the linker thinks
40
 */
41
.space 4096
42
 
160 jermar 43
kernel_image_start:
843 palkovsky 44
	/* Initialize OFW, might be needed before relocate_kernel? */
207 decky 45
	lis r4, ofw@ha
46
	addi r4, r4, ofw@l
47
	stw r5, 0(r4)
185 decky 48
 
207 decky 49
	bl ofw_init
843 palkovsky 50
	bl preboot_read_config
51
 
52
	bl relocate_kernel
53
__after_reloc:
54
	/* Set stack to some more meaningful value */
55
	/* TODO: This is hardcoded for PearPC, must be changed later */
56
	lis r1, 0x70
57
	b main_bsp
207 decky 58
 
843 palkovsky 59
relocate_kernel:
60
	/* TODO: We _know_ that pearpc loads it to 8MB, and
61
	 * but it should be really generic
62
	 */
63
	lis r4, 0x80 /* r4 is where data was loaded - 8MB */
64
 
65
	bl to_real_mode
66
	/* Now we are in real mode, copy first block and jump to it,
67
	 * we are running in the loaded kernel now
68
	 * We still have in r3 physical load kernel address
69
	 */
70
 
71
	b __after_reloc /* We know in pearpc we are ok, so return,
72
	                 * otherwise we should relocate kernel
73
		         * here
74
	                 */
75
 
76
 
77
 
78
 
79
/* Turn off page translation
80
 * - assume that physical-loaded address is in r4
81
 */
82
to_real_mode:
83
	mflr r0
84
 
85
	lis   r5, ktext_start@ha // Expected start of kernel
86
	addi r5, r5, ktext_start@l
87
 
88
	add  r0, r4, r0  	
89
	sub  r0, r0, r5         // r0 now contains physical return address
90
 
91
	mfmsr r3
92
	andis. r3, r3, (~MSR_DR | MSR_IR) >> 16
93
	mtspr SPRN_SRR0, r0
94
	mtspr SPRN_SRR1, r3
95
	sync 			// Really needed? RFI should do it as well?
96
	RFI
97