obs600_locore.S revision 1.6 1 /* $NetBSD: obs600_locore.S,v 1.6 2014/08/05 16:28:39 joerg Exp $ */
2
3 /*
4 * Copyright (c) 2009 KIYOHARA Takashi
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. 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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #undef PPC_4XX_NOCACHE
30
31 #include "opt_ddb.h"
32 #include "opt_ppcarch.h"
33 #include "opt_ppcparam.h"
34 #include "assym.h"
35 #include "ksyms.h"
36
37 #include <machine/param.h>
38 #include <machine/psl.h>
39 #include <machine/trap.h>
40 #include <machine/asm.h>
41
42 #include <powerpc/ibm4xx/spr.h>
43
44 /*
45 * This symbol is here for the benefit of kvm_mkdb, and is supposed to
46 * mark the start of kernel text.
47 */
48 .text
49 .globl _C_LABEL(kernel_text)
50 _C_LABEL(kernel_text):
51
52 /*
53 * Kernel start routine for OpenBlockS600
54 * this code is excuted at the very first after the kernel is loaded
55 * by U-Boot.
56 */
57 .text
58 .globl __start
59 __start:
60 mr %r31, %r3 /* argc of 'go's */
61 mr %r30, %r4 /* argv of 'go's */
62 mr %r29, %r6 /* arg string of 'bootm's */
63
64 li %r0, 0
65 mtmsr %r0 /* Disable FPU/MMU/exceptions */
66 isync
67
68 #ifdef PPC_4XX_NOCACHE
69 /* Disable all caches for physical addresses */
70 li %r0, 0
71 #else
72 /* Allow cacheing for only the first 2GB of RAM */
73 lis %r0, 0xffff
74 #endif
75 mtdccr %r0
76 mticcr %r0
77
78 /* Invalidate all TLB entries */
79 tlbia
80 sync
81 isync
82
83 /* get start of bss */
84 lis %r3, _C_LABEL(_edata)-4@ha
85 addi %r3, %r3, _C_LABEL(_edata)-4@l
86 /* get end of kernel memory */
87 lis %r8, _C_LABEL(end)@ha
88 addi %r8, %r8, _C_LABEL(end)@l
89 /* zero bss */
90 li %r4, 0
91 2: stwu %r4, 4(%r3)
92 cmpw %r3, %r8
93 bne+ 2b
94
95 #if NKSYMS || defined(DDB) || defined(MODULAR)
96 /* If we had symbol table location we'd store it here and would've adjusted r8 here */
97 lis %r7, _C_LABEL(startsym)@ha
98 addi %r7, %r7, _C_LABEL(startsym)@l
99 stw %r8, 0(%r7)
100 lis %r7, _C_LABEL(endsym)@ha
101 addi %r7, %r7, _C_LABEL(endsym)@l
102 stw %r8, 0(%r7)
103 #endif
104
105 /* Set kernel MMU context. */
106 li %r0, KERNEL_PID
107 mtpid %r0
108 sync
109
110 INIT_CPUINFO(8,1,9,0)
111 mr %r4, %r8
112
113 lis %r3, __start@ha
114 addi %r3, %r3, __start@l
115
116 mr %r5, %r31 /* argc of 'go's */
117 mr %r6, %r30 /* argv of 'go's */
118 mr %r7, %r29 /* arg strings of 'bootm's */
119
120 bl _C_LABEL(initppc)
121 bl _C_LABEL(main)
122
123 not_reached:
124 b not_reached
125
126 #include <powerpc/ibm4xx/4xx_locore.S>
127