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>
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
dio_getname(int id)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
dio_find_slow(int deviceid)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 * We don't do the primary+secondary ID encoding thing here. Maybe we should.
120 * (that would break the topcat detection, though. I need to think about
121 * the whole primary/secondary ID thing.)
122 */
123 int scode;
124 u_char prid;
125
126 for (scode = 0; scode < DIO_SCMAX; scode++)
127 {
128 void *va;
129
130 if (DIO_SCINHOLE(scode))
131 continue;
132
133 va = dio_scodetoviraddr(scode);
134 if (!va || !hwreg_present(va + DIO_IDOFF))
135 continue; /* no board present at that select code */
136
137 /* We aren't very likely to want to use this to get at the IHPIB,
138 * but maybe it's returning the same ID as the card we do want...
139 */
140 if (!DIO_ISIHPIB(scode))
141 prid = DIO_ID(va);
142 else
143 prid = DIO_ID_IHPIB;
144
145 if (prid == deviceid)
146 return scode;
147 }
148 return 0;
149 }
150
151 /* Aargh: we use 0 for an error return code, but select code 0 exists!
152 * FIXME (trivial, use -1, but requires changes to all the drivers :-< )
153 */
dio_find(int deviceid)154 int dio_find(int deviceid)
155 {
156 if (blist)
157 {
158 /* fast way */
159 struct dioboard *b;
160 for (b = blist; b; b = b->next)
161 if (b->id == deviceid && b->configured == 0)
162 return b->scode;
163 return 0;
164 }
165 return dio_find_slow(deviceid);
166 }
167
168 /* This is the function that scans the DIO space and works out what
169 * hardware is actually present.
170 */
dio_init(void)171 void __init dio_init(void)
172 {
173 int scode;
174 struct dioboard *b, *bprev = NULL;
175
176 printk("Scanning for DIO devices...\n");
177
178 for (scode = 0; scode < DIO_SCMAX; ++scode)
179 {
180 u_char prid, secid = 0; /* primary, secondary ID bytes */
181 u_char *va;
182
183 if (DIO_SCINHOLE(scode))
184 continue;
185
186 va = dio_scodetoviraddr(scode);
187 if (!va || !hwreg_present(va + DIO_IDOFF))
188 continue; /* no board present at that select code */
189
190 /* Found a board, allocate it an entry in the list */
191 b = kmalloc(sizeof(struct dioboard), GFP_KERNEL);
192
193 /* read the ID byte(s) and encode if necessary. Note workaround
194 * for broken internal HPIB devices...
195 */
196 if (!DIO_ISIHPIB(scode))
197 prid = DIO_ID(va);
198 else
199 prid = DIO_ID_IHPIB;
200
201 if (DIO_NEEDSSECID(prid))
202 {
203 secid = DIO_SECID(va);
204 b->id = DIO_ENCODE_ID(prid, secid);
205 }
206 else
207 b->id = prid;
208
209 b->configured = 0;
210 b->scode = scode;
211 b->ipl = DIO_IPL(va);
212 b->name = dio_getname(b->id);
213 printk("select code %3d: ipl %d: ID %02X", scode, b->ipl, prid);
214 if (DIO_NEEDSSECID(b->id))
215 printk(":%02X", secid);
216 printk(": %s\n", b->name);
217
218 b->next = NULL;
219
220 if (bprev)
221 bprev->next = b;
222 else
223 blist = b;
224 bprev = b;
225 }
226 }
227
228 /* Bear in mind that this is called in the very early stages of initialisation
229 * in order to get the virtual address of the serial port for the console...
230 */
dio_scodetoviraddr(int scode)231 void *dio_scodetoviraddr(int scode)
232 {
233 if (scode > DIOII_SCBASE)
234 {
235 printk("dio_scodetoviraddr: don't support DIO-II yet!\n");
236 return 0;
237 }
238 else if (scode > DIO_SCMAX || scode < 0)
239 return 0;
240 else if (DIO_SCINHOLE(scode))
241 return 0;
242 else if (DIO_ISIHPIB(scode))
243 return (void*)DIO_IHPIBADDR;
244
245 return (void*)(DIO_VIRADDRBASE + DIO_BASE + scode * 0x10000);
246 }
247
dio_scodetoipl(int scode)248 int dio_scodetoipl(int scode)
249 {
250 struct dioboard *b;
251 for (b = blist; b; b = b->next)
252 if (b->scode == scode)
253 break;
254
255 if (!b)
256 {
257 printk("dio_scodetoipl: bad select code %d\n", scode);
258 return 0;
259 }
260 else
261 return b->ipl;
262 }
263
dio_scodetoname(int scode)264 const char *dio_scodetoname(int scode)
265 {
266 struct dioboard *b;
267 for (b = blist; b; b = b->next)
268 if (b->scode == scode)
269 break;
270
271 if (!b)
272 {
273 printk("dio_scodetoname: bad select code %d\n", scode);
274 return NULL;
275 }
276 else
277 return b->name;
278 }
279
dio_config_board(int scode)280 void dio_config_board(int scode)
281 {
282 struct dioboard *b;
283 for (b = blist; b; b = b->next)
284 if (b->scode == scode)
285 break;
286
287 if (!b)
288 printk("dio_config_board: bad select code %d\n", scode);
289 else if (b->configured)
290 printk("dio_config_board: board at select code %d already configured\n", scode);
291 else
292 b->configured = 1;
293 }
294
dio_unconfig_board(int scode)295 void dio_unconfig_board(int scode)
296 {
297 struct dioboard *b;
298 for (b = blist; b; b = b->next)
299 if (b->scode == scode)
300 break;
301
302 if (!b)
303 printk("dio_unconfig_board: bad select code %d\n", scode);
304 else if (!b->configured)
305 printk("dio_unconfig_board: board at select code %d not configured\n",
306 scode);
307 else
308 b->configured = 0;
309 }
310