summaryrefslogtreecommitdiff
path: root/sys/arch/sparc/stand/srt0.S
blob: 36a04cd33d98b1aaa0002cdf4b85cb89e8ad8aec (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
/*	$NetBSD: srt0.S,v 1.5.4.2 1996/07/17 01:51:46 jtc Exp $	*/

/*
 * Copyright (c) 1994 Paul Kranenburg
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Paul Kranenburg.
 * 4. 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.
 */

#include <machine/param.h>
#include <machine/psl.h>

#define	CCFSZ	96

	.file	"str0.s"

	.data
	.global	_cputyp, _nbpg, _pgofset, _pgshift
_cputyp:
	.word	1
_nbpg:
	.word	1
_pgofset:
	.word	1
_pgshift:
	.word	1

	.text	
	.globl	start

start:
	/*
	 * Set up a stack.
	 */
	set	start, %o1
	save	%o1, -CCFSZ, %sp

	/*
	 * Relocate.
	 */
1:	call	2f
	 nop
2:	add	%o7, (start-1b), %l0
	set	start, %l1
	set	_end, %o0
	sub	%o0, %l1, %l2		! length
3:	ld	[%l0], %o0
	add	%l0, 4, %l0
	st	%o0, [%l1]
	subcc	%l2, 4, %l2
	bg	3b
	 add	%l1, 4, %l1

	set	4f, %g1
	jmp	%g1
	 nop

4:
#ifdef notyet
	/*
	 * Enable traps
	 */
	wr	%g0, 0, %wim		! make sure we can set psr
	nop; nop; nop
	wr	%g0, PSR_S|PSR_PS|PSR_PIL, %psr	! set initial psr
	nop; nop; nop
	wr	%g0, 2, %wim		! set initial %wim (w1 invalid)

	rd	%psr, %l0
	wr	%l0, PSR_ET, %psr
	nop; nop; nop
#endif

	/*
	 * Clear BSS
	 */
	set     _edata, %o0             ! bzero(edata, end - edata)
	set     _end, %o1
	call    _bzero
	 sub    %o1, %o0, %o1

	/*
	 * Enable interrupts, but only above level 11. This enables "L1-A",
	 * but avoids spurious interrupt bites from most other devices.
	 */
	rd	%psr, %o0
	andn	%o0, PSR_PIL, %o0
	wr	%o0, 0xb00, %psr	! (11 << 8)
	nop; nop; nop

	/*
	 * Set CPU type that we are running on.
	 */
	sethi	%hi(_cputyp), %o0
	set	0x4000, %g7
	cmp	%i0, %g7
	beq	5f
	 nop

	/*
	 * Save address of PROM vector (passed in %i0).
	 */
	sethi	%hi(_promvec), %o1
	st	%i0, [%o1 + %lo(_promvec)]

	mov	CPU_SUN4C, %g4
	mov	SUN4CM_PGSHIFT, %g5
	b,a	6f

5:
	mov	CPU_SUN4, %g4
	mov	SUN4_PGSHIFT, %g5

6:
	st	%g4, [%o0 + %lo(_cputyp)]
	sethi	%hi(_pgshift), %o0	! pgshift = log2(nbpg)
	st	%g5, [%o0 + %lo(_pgshift)]

	mov	1, %o0			! nbpg = 1 << pgshift
	sll	%o0, %g5, %g5
	sethi	%hi(_nbpg), %o0		! nbpg = bytes in a page
	st	%g5, [%o0 + %lo(_nbpg)]

	sub	%g5, 1, %g5
	sethi	%hi(_pgofset), %o0	! page offset = bytes in a page - 1
	st	%g5, [%o0 + %lo(_pgofset)]

	call	_main
	 mov	%i0, %o0

	ret
	 restore


#ifdef TIGHT

/*
 * XXX - Space saving .div & .rem routines (small & non-negative numbres only)
 */
	.align	4
	.global .div, .udiv
! int n = 0; while (a >= b) { a -= b; n++; }; return n;
.div:
.udiv:
	cmp	%o0, %o1
	bl	2f
	 mov	0, %o5
1:
	sub	%o0, %o1, %o0
	cmp	%o0, %o1
	bge	1b
	 add	%o5, 1, %o5
2:
	retl
	 mov	%o5, %o0

	.align	4
	.global .rem, .urem
! while (a>=b) a -= b; return a;
.rem:
.urem:
	cmp	%o0, %o1
	bl	2f
	 nop
	sub	%o0, %o1, %o0
1:
	cmp	%o0, %o1
	bge,a	1b
	 sub	%o0, %o1, %o0
2:
	retl
	 nop

#endif /* TIGHT */