aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/block/swim_asm.S
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-03-26 19:15:31 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-03-26 19:15:31 -0400
commit4496d937a518fde0d0e1980e4ab470cedb4b50cd (patch)
treea02d57e13b44483417973a306f9fd23743959375 /drivers/block/swim_asm.S
parent8e9d2089723d08d51e66c5eea49253d76e27941e (diff)
parent4b2873ba0bda7dc747cde8b6c7dc6c0b01ea6213 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: m68k: irq_node.handler() should return irqreturn_t m68k: section mismatch fixes: Atari SCSI m68k: section mismatch fixes: DMAsound for Atari MAINTAINERS: Replace dead link to m68k CVS repository by link to new git repository m68k: mac - Add SWIM floppy support m68k: mac - Add a new entry in mac_model to identify the floppy controller type. m68k: Add install target
Diffstat (limited to 'drivers/block/swim_asm.S')
-rw-r--r--drivers/block/swim_asm.S247
1 files changed, 247 insertions, 0 deletions
diff --git a/drivers/block/swim_asm.S b/drivers/block/swim_asm.S
new file mode 100644
index 000000000000..c9668206857b
--- /dev/null
+++ b/drivers/block/swim_asm.S
@@ -0,0 +1,247 @@
1/*
2 * low-level functions for the SWIM floppy controller
3 *
4 * needs assembly language because is very timing dependent
5 * this controller exists only on macintosh 680x0 based
6 *
7 * Copyright (C) 2004,2008 Laurent Vivier <Laurent@lvivier.info>
8 *
9 * based on Alastair Bridgewater SWIM analysis, 2001
10 * based on netBSD IWM driver (c) 1997, 1998 Hauke Fath.
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 *
17 * 2004-08-21 (lv) - Initial implementation
18 * 2008-11-05 (lv) - add get_swim_mode
19 */
20
21 .equ write_data, 0x0000
22 .equ write_mark, 0x0200
23 .equ write_CRC, 0x0400
24 .equ write_parameter,0x0600
25 .equ write_phase, 0x0800
26 .equ write_setup, 0x0a00
27 .equ write_mode0, 0x0c00
28 .equ write_mode1, 0x0e00
29 .equ read_data, 0x1000
30 .equ read_mark, 0x1200
31 .equ read_error, 0x1400
32 .equ read_parameter, 0x1600
33 .equ read_phase, 0x1800
34 .equ read_setup, 0x1a00
35 .equ read_status, 0x1c00
36 .equ read_handshake, 0x1e00
37
38 .equ o_side, 0
39 .equ o_track, 1
40 .equ o_sector, 2
41 .equ o_size, 3
42 .equ o_crc0, 4
43 .equ o_crc1, 5
44
45 .equ seek_time, 30000
46 .equ max_retry, 40
47 .equ sector_size, 512
48
49 .global swim_read_sector_header
50swim_read_sector_header:
51 link %a6, #0
52 moveml %d1-%d5/%a0-%a4,%sp@-
53 movel %a6@(0x0c), %a4
54 bsr mfm_read_addrmark
55 moveml %sp@+, %d1-%d5/%a0-%a4
56 unlk %a6
57 rts
58
59sector_address_mark:
60 .byte 0xa1, 0xa1, 0xa1, 0xfe
61sector_data_mark:
62 .byte 0xa1, 0xa1, 0xa1, 0xfb
63
64mfm_read_addrmark:
65 movel %a6@(0x08), %a3
66 lea %a3@(read_handshake), %a2
67 lea %a3@(read_mark), %a3
68 moveq #-1, %d0
69 movew #seek_time, %d2
70
71wait_header_init:
72 tstb %a3@(read_error - read_mark)
73 moveb #0x18, %a3@(write_mode0 - read_mark)
74 moveb #0x01, %a3@(write_mode1 - read_mark)
75 moveb #0x01, %a3@(write_mode0 - read_mark)
76 tstb %a3@(read_error - read_mark)
77 moveb #0x08, %a3@(write_mode1 - read_mark)
78
79 lea sector_address_mark, %a0
80 moveq #3, %d1
81
82wait_addr_mark_byte:
83
84 tstb %a2@
85 dbmi %d2, wait_addr_mark_byte
86 bpl header_exit
87
88 moveb %a3@, %d3
89 cmpb %a0@+, %d3
90 dbne %d1, wait_addr_mark_byte
91 bne wait_header_init
92
93 moveq #max_retry, %d2
94
95amark0: tstb %a2@
96 dbmi %d2, amark0
97 bpl signal_nonyb
98
99 moveb %a3@, %a4@(o_track)
100
101 moveq #max_retry, %d2
102
103amark1: tstb %a2@
104 dbmi %d2, amark1
105 bpl signal_nonyb
106
107 moveb %a3@, %a4@(o_side)
108
109 moveq #max_retry, %d2
110
111amark2: tstb %a2@
112 dbmi %d2, amark2
113 bpl signal_nonyb
114
115 moveb %a3@, %a4@(o_sector)
116
117 moveq #max_retry, %d2
118
119amark3: tstb %a2@
120 dbmi %d2, amark3
121 bpl signal_nonyb
122
123 moveb %a3@, %a4@(o_size)
124
125 moveq #max_retry, %d2
126
127crc0: tstb %a2@
128 dbmi %d2, crc0
129 bpl signal_nonyb
130
131 moveb %a3@, %a4@(o_crc0)
132
133 moveq #max_retry, %d2
134
135crc1: tstb %a2@
136 dbmi %d2, crc1
137 bpl signal_nonyb
138
139 moveb %a3@, %a4@(o_crc1)
140
141 tstb %a3@(read_error - read_mark)
142
143header_exit:
144 moveq #0, %d0
145 moveb #0x18, %a3@(write_mode0 - read_mark)
146 rts
147signal_nonyb:
148 moveq #-1, %d0
149 moveb #0x18, %a3@(write_mode0 - read_mark)
150 rts
151
152 .global swim_read_sector_data
153swim_read_sector_data:
154 link %a6, #0
155 moveml %d1-%d5/%a0-%a5,%sp@-
156 movel %a6@(0x0c), %a4
157 bsr mfm_read_data
158 moveml %sp@+, %d1-%d5/%a0-%a5
159 unlk %a6
160 rts
161
162mfm_read_data:
163 movel %a6@(0x08), %a3
164 lea %a3@(read_handshake), %a2
165 lea %a3@(read_data), %a5
166 lea %a3@(read_mark), %a3
167 movew #seek_time, %d2
168
169wait_data_init:
170 tstb %a3@(read_error - read_mark)
171 moveb #0x18, %a3@(write_mode0 - read_mark)
172 moveb #0x01, %a3@(write_mode1 - read_mark)
173 moveb #0x01, %a3@(write_mode0 - read_mark)
174 tstb %a3@(read_error - read_mark)
175 moveb #0x08, %a3@(write_mode1 - read_mark)
176
177 lea sector_data_mark, %a0
178 moveq #3, %d1
179
180 /* wait data address mark */
181
182wait_data_mark_byte:
183
184 tstb %a2@
185 dbmi %d2, wait_data_mark_byte
186 bpl data_exit
187
188 moveb %a3@, %d3
189 cmpb %a0@+, %d3
190 dbne %d1, wait_data_mark_byte
191 bne wait_data_init
192
193 /* read data */
194
195 tstb %a3@(read_error - read_mark)
196
197 movel #sector_size-1, %d4 /* sector size */
198read_new_data:
199 movew #max_retry, %d2
200read_data_loop:
201 moveb %a2@, %d5
202 andb #0xc0, %d5
203 dbne %d2, read_data_loop
204 beq data_exit
205 moveb %a5@, %a4@+
206 andb #0x40, %d5
207 dbne %d4, read_new_data
208 beq exit_loop
209 moveb %a5@, %a4@+
210 dbra %d4, read_new_data
211exit_loop:
212
213 /* read CRC */
214
215 movew #max_retry, %d2
216data_crc0:
217
218 tstb %a2@
219 dbmi %d2, data_crc0
220 bpl data_exit
221
222 moveb %a3@, %d5
223
224 moveq #max_retry, %d2
225
226data_crc1:
227
228 tstb %a2@
229 dbmi %d2, data_crc1
230 bpl data_exit
231
232 moveb %a3@, %d5
233
234 tstb %a3@(read_error - read_mark)
235
236 moveb #0x18, %a3@(write_mode0 - read_mark)
237
238 /* return number of bytes read */
239
240 movel #sector_size, %d0
241 addw #1, %d4
242 subl %d4, %d0
243 rts
244data_exit:
245 moveb #0x18, %a3@(write_mode0 - read_mark)
246 moveq #-1, %d0
247 rts