1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1991 The Regents of the University of California.
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32/*
33 * Nec 765 floppy disc controller definitions
34 */
35
36/* Main status register */
37#define NE7_DAB 0x01 /* Diskette drive A is seeking, thus busy */
38#define NE7_DBB 0x02 /* Diskette drive B is seeking, thus busy */
39#define NE7_CB 0x10 /* Diskette Controller Busy */
40#define NE7_NDM 0x20 /* Diskette Controller in Non Dma Mode */
41#define NE7_DIO 0x40 /* Diskette Controller Data register I/O */
42#define NE7_RQM 0x80 /* Diskette Controller ReQuest for Master */
43
44/* Status register ST0 */
45#define NE7_ST0BITS "\020\010invld\007abnrml\006seek_cmplt\005equ_chck\004drive_notrdy\003top_head"
46
47#define NE7_ST0_IC 0xc0 /* interrupt completion code */
48
49#define NE7_ST0_IC_RC 0xc0 /* terminated due to ready changed, n/a */
50#define NE7_ST0_IC_IV 0x80 /* invalid command; must reset FDC */
51#define NE7_ST0_IC_AT 0x40 /* abnormal termination, check error stat */
52#define NE7_ST0_IC_NT 0x00 /* normal termination */
53
54#define NE7_ST0_SE 0x20 /* seek end */
55#define NE7_ST0_EC 0x10 /* equipment check, recalibrated but no trk0 */
56#define NE7_ST0_NR 0x08 /* not ready (n/a) */
57#define NE7_ST0_HD 0x04 /* upper head selected */
58#define NE7_ST0_DR 0x03 /* drive code */
59
60/* Status register ST1 */
61#define NE7_ST1BITS "\020\010end_of_cyl\006bad_crc\005data_overrun\003sec_not_fnd\002write_protect\001no_am"
62
63#define NE7_ST1_EN 0x80 /* end of cylinder, access past last record */
64#define NE7_ST1_DE 0x20 /* data error, CRC fail in ID or data */
65#define NE7_ST1_OR 0x10 /* DMA overrun, DMA failed to do i/o quickly */
66#define NE7_ST1_ND 0x04 /* no data, sector not found or CRC in ID f. */
67#define NE7_ST1_NW 0x02 /* not writeable, attempt to violate WP */
68#define NE7_ST1_MA 0x01 /* missing address mark (in ID or data field)*/
69
70/* Status register ST2 */
71#define NE7_ST2BITS "\020\007ctrl_mrk\006bad_crc\005wrong_cyl\004scn_eq\003scn_not_fnd\002bad_cyl\001no_dam"
72
73#define NE7_ST2_CM 0x40 /* control mark; found deleted data */
74#define NE7_ST2_DD 0x20 /* data error in data field, CRC fail */
75#define NE7_ST2_WC 0x10 /* wrong cylinder, ID field mismatches cmd */
76#define NE7_ST2_SH 0x08 /* scan equal hit */
77#define NE7_ST2_SN 0x04 /* scan not satisfied */
78#define NE7_ST2_BC 0x02 /* bad cylinder, cylinder marked 0xff */
79#define NE7_ST2_MD 0x01 /* missing address mark in data field */
80
81/* Status register ST3 */
82#define NE7_ST3BITS "\020\010fault\007write_protect\006drdy\005tk0\004two_side\003side_sel\002"
83
84#define NE7_ST3_FT 0x80 /* fault; PC: n/a */
85#define NE7_ST3_WP 0x40 /* write protected */
86#define NE7_ST3_RD 0x20 /* ready; PC: always true */
87#define NE7_ST3_T0 0x10 /* track 0 */
88#define NE7_ST3_TS 0x08 /* two-sided; PC: n/a */
89#define NE7_ST3_HD 0x04 /* upper head select */
90#define NE7_ST3_US 0x03 /* unit select */
91
92/* Data Rate Select Register DSR (enhanced controller) */
93#define I8207X_DSR_SR 0x80 /* software reset */
94#define I8207X_DSR_LP 0x40 /* low power */
95#define I8207X_DSR_PS 0x1c /* precompensation select */
96#define I8207X_DSR_RS 0x03 /* data rate select */
97
98/* Commands */
99/*
100 * the top three bits -- where appropriate -- are set as follows:
101 *
102 * MT - multi-track; allow both sides to be handled in single cmd
103 * MFM - modified frequency modulation; use MFM encoding
104 * SK - skip; skip sectors marked as "deleted"
105 */
106
107#define NE7CMD_MT 0x80 /* READ, WRITE, WRITEDEL, READDEL, SCAN* */
108#define NE7CMD_MFM 0x40 /* same as MT, plus READTRK, READID, FORMAT */
109#define NE7CMD_SK 0x20 /* READ, READDEL, SCAN* */
110
111#define NE7CMD_READTRK 0x02 /* read whole track */
112#define NE7CMD_SPECIFY 0x03 /* specify drive parameters - requires unit
113 * parameters byte */
114#define NE7CMD_SENSED 0x04 /* sense drive - requires unit select byte */
115#define NE7CMD_WRITE 0x05 /* write - requires eight additional bytes */
116#define NE7CMD_READ 0x06 /* read - requires eight additional bytes */
117#define NE7CMD_RECAL 0x07 /* recalibrate drive - requires
118 * unit select byte */
119#define NE7CMD_SENSEI 0x08 /* sense controller interrupt status */
120#define NE7CMD_WRITEDEL 0x09 /* write deleted data */
121#define NE7CMD_READID 0x0a /* read ID field */
122#define NE7CMD_READDEL 0x0c /* read deleted data */
123#define NE7CMD_FORMAT 0x0d /* format - requires five additional bytes */
124#define NE7CMD_SEEK 0x0f /* seek drive - requires unit select byte
125 * and new cyl byte */
126#define NE7CMD_VERSION 0x10 /* get version */
127#define NE7CMD_SCNEQU 0x11 /* scan equal */
128#define NE7CMD_SCNLE 0x19 /* scan less or equal */
129#define NE7CMD_SCNGE 0x1d /* scan greater or equal */
130
131/*
132 * Enhanced controller commands:
133 */
134#define I8207X_DUMPREG 0x0e /* dump internal registers */
135#define I8207X_CONFIG 0x13 /* configure enhanced features */
136
137/*
138 * "specify" definitions
139 *
140 * acronyms (times are relative to a FDC clock of 8 MHz):
141 * srt - step rate; PC usually 3 ms
142 * hut - head unload time; PC usually maximum of 240 ms
143 * hlt - head load time; PC usually minimum of 2 ms
144 * nd - no DMA flag; PC usually not set (0)
145 */
146
147#define NE7_SPEC_1(srt, hut) (((16 - (srt)) << 4) | (((hut) / 16)))
148#define NE7_SPEC_2(hlt, nd) (((hlt) & 0xFE) | ((nd) & 1))