1/*	$NetBSD: wdb00t.ahdi.S,v 1.1.4.3 2004/09/21 13:14:11 skrll 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	movb	%d5,%d1			| NVRAM bootpref
62	bnes	0f
63
64	| The Hades bios does not provide a bootprev. In case
65	| of doubt, we fetch it ourselves.
66	movb	#BOOTPREF,rtcrnr:w
67	movb	rtcdat:w,%d1
68	bnes	0f
69	movq	#-8,%d1	 		| bootpref = any
70
710:	movb	%a0@,%d2			| bootflags
72	btst	#0,%d2
73	beqs	1f
74	andb	%d1,%d2
75	bnes	boot
761:	lea	%a0@(12),%a0
77	dbra	%d0,0b
78
79exit:	movml	%sp@+,%d3/%d5
80tostst:	clrw	_bootdev:w
81	movl	_sysbase:w,%a0
82	movl	%a0@(24),%d0
83	swap	%d0
84	cmpl	#0x19870422,%d0		| old TOS?
85	bccs	0f			| no
86	movw	#0xe0,%d7
870:	rts
88
89boot:	movl	%a0@(4),%d6
90	movq	#1,%d5
91	lea	%pc@(end),%a4
92	bsrs	rds0
93	tstw	%d0
94	bnes	exit
95	movl	%a4,%a0
96	movw	#0xff,%d0
97	movq	#0,%d1
980:	addw	%a0@+,%d1
99	dbra	%d0,0b
100	cmpw	#0x1234,%d1
101	bnes	exit
102	lea	%pc@(rds0),%a3
103	lea	%pc@(tostst),%a5
104	movml	%sp@+,%d3/%d5
105	jmp	%a4@			| start bootsector code
106/*
107 * in:  d4 (target) d5 (count), d6 (offset), a4 (buffer)
108 * out: d0 (<= 0)
109 * mod: d0, d1, d2, a0, a1, a5, a6
110 */
111rds0:	lea	%pc@(dpar),%a6
112	tstb	%a6@
113	bnes	0f
114	movb	%d4,%d0
115	andb	#1,%d0
116	aslb	#4,%d0
117	orb	#0xa0,%d0
118	movb	%d0,idesdh:l
119	movl	%a4,%a0
120	movq	#0,%d1
121	movb	#0,idedor:l
122	movb	#0xec,idecr:l		| IDENTIFY DRIVE
123	bsrs	wait
124	bnes	err
125	movb	%a4@(7),%a6@		| tracks/cylinder
126	movb	%a4@(13),%a6@(1)		| sectors/track
1270:	movl	%d6,%d1
128	movq	#0,%d0
129	movb	%a6@(1),%d0
130	movq	#0,%d2
131	movb	%a6@,%d2
132	mulu	%d0,%d2
133	divu	%d2,%d1
134	movb	%d1,idecl:l
135	lsrl	#8,%d1
136	movb	%d1,idech:l
137	lsrl	#8,%d1
138	divu	%d0,%d1
139	movb	%d4,%d0
140	andb	#1,%d0
141	aslb	#4,%d0
142	orb	%d0,%d1
143	orb	#0xa0,%d1
144	movb	%d1,idesdh:l
145	swap	%d1
146	addqw	#1,%d1
147	movb	%d1,idesn:l
148	movl	%a4,%a0
149	movb	%d5,idesc:l
150	movw	%d5,%d1
151	subqw	#1,%d1
152	movb	#0,idedor:l
153	movb	#0x20,idecr:l
154wait:	movl	#0x7d0,%d0
155	addl	_hz_200:w,%d0
1562:	btst	#5,gpip:w
157	beqs	3f
158	cmpl	_hz_200:w,%d0
159	bhis	2b
160err:	movq	#-1,%d0
161	rts
1623:	movb	idesr:l,%d0
163	btst	#0,%d0
164	bnes	err
165	btst	#3,%d0
166	beqs	err
167	movq	#63,%d0
168	lea	idedr:l,%a1
1694:	movw	%a1@,%a0@+
170	movw	%a1@,%a0@+
171	movw	%a1@,%a0@+
172	movw	%a1@,%a0@+
173	dbra	%d0,4b
174	dbra	%d1,wait
175	movq	#0,%d0
176	rts
177
178fill:	.space	52
179
180dpar:	.byte	0			| tracks/cylinder
181	.byte	0			| sectors/track
182	.ascii	"NetBSD"
183hd_siz:	.long	0
184p0_dsc:	.long	0, 0, 0
185p1_dsc:	.long	0, 0, 0
186p2_dsc:	.long	0, 0, 0
187p3_dsc:	.long	0, 0, 0
188bsl_st:	.long	0
189bsl_sz:	.long	0
190	.word	0
191end:
192