xref: /netbsd-src/sys/arch/atari/stand/xxboot/ahdi-sdb00t/sdb00t.ahdi.S (revision 9fb66d812c00ebfb445c0b47dea128f32aa6fe96)
1/*	$NetBSD: sdb00t.ahdi.S,v 1.2 2005/12/11 12:17:02 christos Exp $	*/
2
3/*
4 * Copyright (c) 1995 Waldi Ravens
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 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *        This product includes software developed by Waldi Ravens.
18 * 4. The name of the author may not be used to endorse or promote products
19 *    derived from this software without specific prior written permission
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33#include "xxboot.h"
34
35#ifdef __ELF__
36	.globl	_start, main, fill
37
38	.text
39
40_start:	bras	main
41#else
42	.globl	start, main, fill
43
44	.text
45
46start:	bras	main
47#endif
48	bra	rds0
49
50main:	bclr	#2,(_drvbits+3):w
51	clrl	pun_ptr:w
52	movml	%d3/%d5,%sp@-
53	movw	#-1,%sp@-
54	movw	#Kbshift,%sp@-
55	trap	#BIOS
56	addql	#4,%sp
57	btst	#3,%d0			| Alternate?
58	bnes	exit
59	movq	#3,%d0
60	lea	%pc@(p0_dsc),%a0
61	cmpl	#0x444d4172,%d3		| SCSI bootdev?
62	beqs	0f
63	movq	#-1,%d4			| no, ACSI
64	movq	#0,%d5
650:	movb	%d5,%d1			| NVRAM bootpref
66	bnes	1f
67
68	| The Hades bios does not provide a bootprev. In case
69	| of doubt, we fetch it ourselves.
70 	moveml	%d0-%d2/%a0-%a2,%sp@-
71 	pea	bpref
72 	movw	#1, %sp@-
73 	movw	#1, %sp@-
74 	movw	#0, %sp@-
75 	movw	#NVMaccess, %sp@-
76 	trap	#XBIOS
77 	lea	%sp@(12),%sp
78 	moveml	%sp@+,%d0-%d2/%a0-%a2
79 	movb	bpref:w,%d1
80	bnes	1f
81	movq	#-8,%d1	 		| bootpref = any
82
831:	movb	%a0@,%d2			| bootflags
84	btst	#0,%d2
85	beqs	2f
86	andb	%d1,%d2
87	bnes	boot
882:	lea	%a0@(12),%a0
89	dbra	%d0,1b
90
91exit:	movml	%sp@+,%d3/%d5
92tostst:	clrw	_bootdev:w
93	movl	_sysbase:w,%a0
94	movl	%a0@(24),%d0
95	swap	%d0
96	cmpl	#0x19870422,%d0		| old TOS?
97	bccs	0f			| no
98	movw	#0xe0,%d7
990:	rts
100
101boot:	movl	%a0@(4),%d6
102	movq	#1,%d5
103	lea	%pc@(end),%a4
104	bsrs	rds0
105	tstw	%d0
106	bnes	exit
107	movl	%a4,%a0
108	movw	#0xff,%d0
109	movq	#0,%d1
1100:	addw	%a0@+,%d1
111	dbra	%d0,0b
112	cmpw	#0x1234,%d1
113	bnes	exit
114	lea	%pc@(rds0),%a3
115	lea	%pc@(tostst),%a5
116	movml	%sp@+,%d3/%d5
117	jmp	%a4@			| start bootsector code
118/*
119 * in:  d4/d7 (target) d5 (count), d6 (offset), a4 (buffer)
120 * out: d0 (<= 0)
121 * mod: d0, d1, d2, a0, a1, a5, a6
122 */
123rds0:	tstl	%d4
124	bmis	0f
125	movw	%d4,%sp@-			| device
126	pea	%a4@			| buffer
127	movw	%d5,%sp@-			| count
128	movl	%d6,%sp@-			| offset
129	movw	#DMAread,%sp@-
130	trap	#XBIOS
131	lea	%sp@(14),%sp
132	rts
133
1340:	st	flock:w
135	movl	_hz_200:w,%d0
136	addql	#2,%d0
1371:	cmpl	_hz_200:w,%d0
138	bccs	1b
139	movml	%d6/%a4,%sp@-
140	lea	dmahi:w,%a6
141	movb	%sp@(7),%a6@(4)
142	movb	%sp@(6),%a6@(2)
143	movb	%sp@(5),%a6@
144	lea	%pc@(r0com),%a6
145	movb	%sp@(1),%a6@(1)
146	movb	%sp@(2),%a6@(5)
147	movb	%sp@(3),%a6@(9)
148	movb	%d5,%a6@(13)
149	addql	#8,%sp
150	lea	dmodus:w,%a6
151	lea	daccess:w,%a5
152	movw	#0x198,%a6@
153	movw	#0x098,%a6@
154	movw	%d5,%a5@
155	movw	#0x88,%a6@
156	movq	#0,%d0
157	movb	%d7,%d0
158	orb	#0x08,%d0
159	swap	%d0
160	movw	#0x8a,%d0
161	bsrs	shake
162	lea	%pc@(r0com),%a0
163	movq	#3,%d2
1642:	movl	%a0@+,%d0
165	bsrs	shake
166	dbra	%d2,2b
167	movq	#0x0a,%d0
168	movl	%d0,%a5@
169	movl	#0x190,%d1
170	bsrs	wait
171	movw	#0x8a,%a6@
172	movw	%a5@,%d0
173	andw	#0xff,%d0
174	beqs	0f
175r0err:	movq	#-1,%d0
1760:	movw	#0x80,%a6@
177	clrb	flock:w
178r0ret:	rts
179
180shake:	movl	%d0,%a5@
181	movq	#0x0a,%d1
182wait:	addl	_hz_200:w,%d1
1830:	btst	#5,gpip:w
184	beqs	r0ret
185	cmpl	_hz_200:w,%d1
186	bccs	0b
187	addql	#4,%sp
188	bras	r0err
189
190r0com:	.long	0x0000008a
191	.long	0x0000008a
192	.long	0x0000008a
193	.long	0x0001008a
194bpref:	.word	0
195
196fill:	.space	16
197
198	.ascii	"NetBSD"
199hd_siz:	.long	0
200p0_dsc:	.long	0, 0, 0
201p1_dsc:	.long	0, 0, 0
202p2_dsc:	.long	0, 0, 0
203p3_dsc:	.long	0, 0, 0
204bsl_st:	.long	0
205bsl_sz:	.long	0
206	.word	0
207end:
208