File: /usr/src/linux/drivers/dio/dio.c
1 /* Code to support devices on the DIO (and eventually DIO-II) bus
2 * Copyright (C) 05/1998 Peter Maydell <pmaydell@chiark.greenend.org.uk>
3 *
4 * This code has basically these routines at the moment:
5 * int dio_find(u_int deviceid)
6 * Search the list of DIO devices and return the select code
7 * of the next unconfigured device found that matches the given device ID.
8 * Note that the deviceid parameter should be the encoded ID.
9 * This means that framebuffers should pass it as
10 * DIO_ENCODE_ID(DIO_ID_FBUFFER,DIO_ID2_TOPCAT)
11 * (or whatever); everybody else just uses DIO_ID_FOOBAR.
12 * void *dio_scodetoviraddr(int scode)
13 * Return the virtual address corresponding to the given select code.
14 * NB: DIO-II devices will have to be mapped in in this routine!
15 * int dio_scodetoipl(int scode)
16 * Every DIO card has a fixed interrupt priority level. This function
17 * returns it, whatever it is.
18 * const char *dio_scodetoname(int scode)
19 * Return a character string describing this board [might be "" if
20 * not CONFIG_DIO_CONSTANTS]
21 * void dio_config_board(int scode) mark board as configured in the list
22 * void dio_unconfig_board(int scode) mark board as no longer configured
23 *
24 * This file is based on the way the Amiga port handles Zorro II cards,
25 * although we aren't so complicated...
26 */
27 #include <linux/config.h>
28 #include <linux/kernel.h>
29 #include <linux/types.h>
30 #include <linux/dio.h>
31 #include <linux/slab.h> /* kmalloc() */
32 #include <linux/init.h>
33 #include <asm/hwtest.h> /* hwreg_present() */
34 #include <asm/io.h> /* readb() */
35 /* not a real config option yet! */
36 #define CONFIG_DIO_CONSTANTS
37
38 #ifdef CONFIG_DIO_CONSTANTS
39 /* We associate each numeric ID with an appropriate descriptive string
40 * using a constant array of these structs.
41 * FIXME: we should be able to arrange to throw away most of the strings
42 * using the initdata stuff. Then we wouldn't need to worry about
43 * carrying them around...
44 * I think we do this by copying them into newly kmalloc()ed memory and
45 * marking the names[] array as .initdata ?
46 */
47 struct dioname
48 {
49 int id;
50 const char *name;
51 };
52
53 /* useful macro */
54 #define DIONAME(x) { DIO_ID_##x, DIO_DESC_##x }
55 #define DIOFBNAME(x) { DIO_ENCODE_ID( DIO_ID_FBUFFER, DIO_ID2_##x), DIO_DESC2_##x }
56
57 static struct dioname names[] =
58 {
59 DIONAME(DCA0), DIONAME(DCA0REM), DIONAME(DCA1), DIONAME(DCA1REM),
60 DIONAME(DCM), DIONAME(DCMREM),
61 DIONAME(LAN),
62 DIONAME(FHPIB), DIONAME(NHPIB), DIONAME(IHPIB),
63 DIONAME(SCSI0), DIONAME(SCSI1), DIONAME(SCSI2), DIONAME(SCSI3),
64 DIONAME(FBUFFER),
65 DIONAME(PARALLEL), DIONAME(VME), DIONAME(DCL), DIONAME(DCLREM),
66 DIONAME(MISC0), DIONAME(MISC1), DIONAME(MISC2), DIONAME(MISC3),
67 DIONAME(MISC4), DIONAME(MISC5), DIONAME(MISC6), DIONAME(MISC7),
68 DIONAME(MISC8), DIONAME(MISC9), DIONAME(MISC10), DIONAME(MISC11),
69 DIONAME(MISC12), DIONAME(MISC13),
70 DIOFBNAME(GATORBOX), DIOFBNAME(TOPCAT), DIOFBNAME(RENAISSANCE),
71 DIOFBNAME(LRCATSEYE), DIOFBNAME(HRCCATSEYE), DIOFBNAME(HRMCATSEYE),
72 DIOFBNAME(DAVINCI), DIOFBNAME(XXXCATSEYE), DIOFBNAME(HYPERION),
73 DIOFBNAME(XGENESIS), DIOFBNAME(TIGER), DIOFBNAME(YGENESIS)
74 };
75
76 #undef DIONAME
77 #undef DIOFBNAME
78
79 #define NUMNAMES (sizeof(names) / sizeof(struct dioname))
80
81 static const char *unknowndioname
82 = "unknown DIO board -- please email <pmaydell@chiark.greenend.org.uk>!";
83
84 static const char *dio_getname(int id)
85 {
86 /* return pointer to a constant string describing the board with given ID */
87 unsigned int i;
88 for (i = 0; i < NUMNAMES; i++)
89 if (names[i].id == id)
90 return names[i].name;
91
92 return unknowndioname;
93 }
94
95 #else
96
97 static char dio_no_name[] = { 0 };
98 #define dio_getname(_id) (dio_no_name)
99
100 #endif /* CONFIG_DIO_CONSTANTS */
101
102 /* We represent all the DIO boards in the system with a linked list of these structs. */
103 struct dioboard
104 {
105 struct dioboard *next; /* link to next struct in list */
106 int ipl; /* IPL of this board */
107 int configured; /* has this board been configured? */
108 int scode; /* select code of this board */
109 int id; /* encoded ID */
110 const char *name;
111 };
112
113 static struct dioboard *blist = NULL;
114
115 static int __init dio_find_slow(int deviceid)
116 {
117 /* Called to find a DIO device before the full bus scan has run. Basically
118 only used by the console driver. */
119 int scode;
120 for (scode = 0; scode < DIO_SCMAX; scode++)
121 {
122 void *va;
123
124 if (DIO_SCINHOLE(scode))
125 continue;
126
127 va = dio_scodetoviraddr(scode);
128 if (!va || !hwreg_present(va + DIO_IDOFF))
129 continue; /* no board present at that select code */
130
131 if (DIO_ID(va) == deviceid)
132 return scode;
133 }
134 return 0;
135 }
136
137 int dio_find(int deviceid)
138 {
139 if (blist)
140 {
141 /* fast way */
142 struct dioboard *b;
143 for (b = blist; b; b = b->next)
144 if (b->id == deviceid && b->configured == 0)
145 return b->scode;
146 return 0;
147 }
148 return dio_find_slow(deviceid);
149 }
150
151 /* This is the function that scans the DIO space and works out what
152 * hardware is actually present.
153 */
154 void __init dio_init(void)
155 {
156 int scode;
157 struct dioboard *b, *bprev = NULL;
158
159 printk("Scanning for DIO devices...\n");
160
161 for (scode = 0; scode < DIO_SCMAX; ++scode)
162 {
163 u_char prid, secid = 0; /* primary, secondary ID bytes */
164 u_char *va;
165
166 if (DIO_SCINHOLE(scode))
167 continue;
168
169 va = dio_scodetoviraddr(scode);
170 if (!va || !hwreg_present(va + DIO_IDOFF))
171 continue; /* no board present at that select code */
172
173 /* Found a board, allocate it an entry in the list */
174 b = kmalloc(sizeof(struct dioboard), GFP_KERNEL);
175
176 /* read the ID byte(s) and encode if necessary. Note workaround
177 * for broken internal HPIB devices...
178 */
179 if (!DIO_ISIHPIB(scode))
180 prid = DIO_ID(va);
181 else
182 prid = DIO_ID_IHPIB;
183
184 if (DIO_NEEDSSECID(prid))
185 {
186 secid = DIO_SECID(va);
187 b->id = DIO_ENCODE_ID(prid, secid);
188 }
189 else
190 b->id = prid;
191
192 b->configured = 0;
193 b->scode = scode;
194 b->ipl = DIO_IPL(va);
195 b->name = dio_getname(b->id);
196 printk("select code %3d: ID %02X", scode, prid);
197 if (DIO_NEEDSSECID(b->id))
198 printk(":%02X", secid);
199 printk(" %s\n", b->name);
200
201 b->next = NULL;
202
203 if (bprev)
204 bprev->next = b;
205 else
206 blist = b;
207 bprev = b;
208 }
209 }
210
211 /* Bear in mind that this is called in the very early stages of initialisation
212 * in order to get the virtual address of the serial port for the console...
213 */
214 void *dio_scodetoviraddr(int scode)
215 {
216 if (scode > DIOII_SCBASE)
217 {
218 printk("dio_scodetoviraddr: don't support DIO-II yet!\n");
219 return 0;
220 }
221 else if (scode > DIO_SCMAX || scode < 0)
222 return 0;
223 else if (DIO_SCINHOLE(scode))
224 return 0;
225 else if (scode == DIO_IHPIBSCODE) /* this should really be #ifdef CONFIG_IHPIB */
226 return (void*)DIO_IHPIBADDR; /* or something similar... */
227
228 return (void*)(DIO_VIRADDRBASE + DIO_BASE + scode * 0x10000);
229 }
230
231 int dio_scodetoipl(int scode)
232 {
233 struct dioboard *b;
234 for (b = blist; b; b = b->next)
235 if (b->scode == scode)
236 break;
237
238 if (!b)
239 {
240 printk("dio_scodetoipl: bad select code %d\n", scode);
241 return 0;
242 }
243 else
244 return b->ipl;
245 }
246
247 const char *dio_scodetoname(int scode)
248 {
249 struct dioboard *b;
250 for (b = blist; b; b = b->next)
251 if (b->scode == scode)
252 break;
253
254 if (!b)
255 {
256 printk("dio_scodetoname: bad select code %d\n", scode);
257 return NULL;
258 }
259 else
260 return b->name;
261 }
262
263 void dio_config_board(int scode)
264 {
265 struct dioboard *b;
266 for (b = blist; b; b = b->next)
267 if (b->scode == scode)
268 break;
269
270 if (!b)
271 printk("dio_config_board: bad select code %d\n", scode);
272 else if (b->configured)
273 printk("dio_config_board: board at select code %d already configured\n", scode);
274 else
275 b->configured = 1;
276 }
277
278 void dio_unconfig_board(int scode)
279 {
280 struct dioboard *b;
281 for (b = blist; b; b = b->next)
282 if (b->scode == scode)
283 break;
284
285 if (!b)
286 printk("dio_unconfig_board: bad select code %d\n", scode);
287 else if (!b->configured)
288 printk("dio_unconfig_board: board at select code %d not configured\n",
289 scode);
290 else
291 b->configured = 0;
292 }
293