1 /*
2  * Routines common to all CFI-type probes.
3  * (C) 2001, 2001 Red Hat, Inc.
4  * GPL'd
5  * $Id: gen_probe.c,v 1.9 2002/09/05 05:15:32 acurtis Exp $
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/mtd/mtd.h>
10 #include <linux/mtd/map.h>
11 #include <linux/mtd/cfi.h>
12 #include <linux/mtd/gen_probe.h>
13 
14 static struct mtd_info *check_cmd_set(struct map_info *, int);
15 static struct cfi_private *genprobe_ident_chips(struct map_info *map,
16 						struct chip_probe *cp);
17 static int genprobe_new_chip(struct map_info *map, struct chip_probe *cp,
18 			     struct cfi_private *cfi);
19 
mtd_do_chip_probe(struct map_info * map,struct chip_probe * cp)20 struct mtd_info *mtd_do_chip_probe(struct map_info *map, struct chip_probe *cp)
21 {
22 	struct mtd_info *mtd = NULL;
23 	struct cfi_private *cfi;
24 
25 	/* First probe the map to see if we have CFI stuff there. */
26 	cfi = genprobe_ident_chips(map, cp);
27 
28 	if (!cfi)
29 		return NULL;
30 
31 	map->fldrv_priv = cfi;
32 	/* OK we liked it. Now find a driver for the command set it talks */
33 
34 	mtd = check_cmd_set(map, 1); /* First the primary cmdset */
35 	if (!mtd)
36 		mtd = check_cmd_set(map, 0); /* Then the secondary */
37 
38 	if (mtd)
39 		return mtd;
40 
41 	printk(KERN_WARNING"gen_probe: No supported Vendor Command Set found\n");
42 
43 	kfree(cfi->cfiq);
44 	kfree(cfi);
45 	map->fldrv_priv = NULL;
46 	return NULL;
47 }
48 EXPORT_SYMBOL(mtd_do_chip_probe);
49 
50 
genprobe_ident_chips(struct map_info * map,struct chip_probe * cp)51 struct cfi_private *genprobe_ident_chips(struct map_info *map, struct chip_probe *cp)
52 {
53 	unsigned long base=0;
54 	struct cfi_private cfi;
55 	struct cfi_private *retcfi;
56 	struct flchip chip[MAX_CFI_CHIPS];
57 	int i;
58 
59 	memset(&cfi, 0, sizeof(cfi));
60 
61 	/* Call the probetype-specific code with all permutations of
62 	   interleave and device type, etc. */
63 	if (!genprobe_new_chip(map, cp, &cfi)) {
64 		/* The probe didn't like it */
65 		printk(KERN_WARNING "%s: Found no %s device at location zero\n",
66 		       cp->name, map->name);
67 		return NULL;
68 	}
69 
70 #if 0 /* Let the CFI probe routine do this sanity check. The Intel and AMD
71 	 probe routines won't ever return a broken CFI structure anyway,
72 	 because they make them up themselves.
73       */
74 	if (cfi.cfiq->NumEraseRegions == 0) {
75 		printk(KERN_WARNING "Number of erase regions is zero\n");
76 		kfree(cfi.cfiq);
77 		return NULL;
78 	}
79 #endif
80 	chip[0].start = 0;
81 	chip[0].state = FL_READY;
82 	cfi.chipshift = cfi.cfiq->DevSize;
83 
84 	switch(cfi.interleave) {
85 #ifdef CFIDEV_INTERLEAVE_1
86 	case 1:
87 		break;
88 #endif
89 #ifdef CFIDEV_INTERLEAVE_2
90 	case 2:
91 		cfi.chipshift++;
92 		break;
93 #endif
94 #ifdef CFIDEV_INTERLEAVE_4
95 	case 4:
96 		cfi.chipshift+=2;
97 		break;
98 #endif
99 	default:
100 		BUG();
101 	}
102 
103 	cfi.numchips = 1;
104 
105 	/*
106 	 * Now probe for other chips, checking sensibly for aliases while
107 	 * we're at it. The new_chip probe above should have let the first
108 	 * chip in read mode.
109 	 *
110 	 * NOTE: Here, we're checking if there is room for another chip
111 	 *       the same size within the mapping. Therefore,
112 	 *       base + chipsize <= map->size is the correct thing to do,
113 	 *       because, base + chipsize would be the  _first_ byte of the
114 	 *       next chip, not the one we're currently pondering.
115 	 */
116 
117 	for (base = (1<<cfi.chipshift); base + (1<<cfi.chipshift) <= map->size;
118 	     base += (1<<cfi.chipshift))
119 		cp->probe_chip(map, base, &chip[0], &cfi);
120 
121 	/*
122 	 * Now allocate the space for the structures we need to return to
123 	 * our caller, and copy the appropriate data into them.
124 	 */
125 
126 	retcfi = kmalloc(sizeof(struct cfi_private) + cfi.numchips * sizeof(struct flchip), GFP_KERNEL);
127 
128 	if (!retcfi) {
129 		printk(KERN_WARNING "%s: kmalloc failed for CFI private structure\n", map->name);
130 		kfree(cfi.cfiq);
131 		return NULL;
132 	}
133 
134 	memcpy(retcfi, &cfi, sizeof(cfi));
135 	memcpy(&retcfi->chips[0], chip, sizeof(struct flchip) * cfi.numchips);
136 
137 	/* Fix up the stuff that breaks when you move it */
138 	for (i=0; i< retcfi->numchips; i++) {
139 		init_waitqueue_head(&retcfi->chips[i].wq);
140 		spin_lock_init(&retcfi->chips[i]._spinlock);
141 		retcfi->chips[i].mutex = &retcfi->chips[i]._spinlock;
142 	}
143 
144 	return retcfi;
145 }
146 
147 
genprobe_new_chip(struct map_info * map,struct chip_probe * cp,struct cfi_private * cfi)148 static int genprobe_new_chip(struct map_info *map, struct chip_probe *cp,
149 			     struct cfi_private *cfi)
150 {
151 	switch (map->buswidth) {
152 #ifdef CFIDEV_BUSWIDTH_1
153 	case CFIDEV_BUSWIDTH_1:
154 		cfi->interleave = CFIDEV_INTERLEAVE_1;
155 
156 		cfi->device_type = CFI_DEVICETYPE_X8;
157 		if (cp->probe_chip(map, 0, NULL, cfi))
158 			return 1;
159 
160 		cfi->device_type = CFI_DEVICETYPE_X16;
161 		if (cp->probe_chip(map, 0, NULL, cfi))
162 			return 1;
163 		break;
164 #endif /* CFIDEV_BUSWITDH_1 */
165 
166 #ifdef CFIDEV_BUSWIDTH_2
167 	case CFIDEV_BUSWIDTH_2:
168 #ifdef CFIDEV_INTERLEAVE_1
169 		cfi->interleave = CFIDEV_INTERLEAVE_1;
170 
171 		cfi->device_type = CFI_DEVICETYPE_X16;
172 		if (cp->probe_chip(map, 0, NULL, cfi))
173 			return 1;
174 #endif /* CFIDEV_INTERLEAVE_1 */
175 #ifdef CFIDEV_INTERLEAVE_2
176 		cfi->interleave = CFIDEV_INTERLEAVE_2;
177 
178 		cfi->device_type = CFI_DEVICETYPE_X8;
179 		if (cp->probe_chip(map, 0, NULL, cfi))
180 			return 1;
181 
182 		cfi->device_type = CFI_DEVICETYPE_X16;
183 		if (cp->probe_chip(map, 0, NULL, cfi))
184 			return 1;
185 #endif /* CFIDEV_INTERLEAVE_2 */
186 		break;
187 #endif /* CFIDEV_BUSWIDTH_2 */
188 
189 #ifdef CFIDEV_BUSWIDTH_4
190 	case CFIDEV_BUSWIDTH_4:
191 #if defined(CFIDEV_INTERLEAVE_1) && defined(SOMEONE_ACTUALLY_MAKES_THESE)
192                 cfi->interleave = CFIDEV_INTERLEAVE_1;
193 
194                 cfi->device_type = CFI_DEVICETYPE_X32;
195 		if (cp->probe_chip(map, 0, NULL, cfi))
196 			return 1;
197 #endif /* CFIDEV_INTERLEAVE_1 */
198 #ifdef CFIDEV_INTERLEAVE_2
199 		cfi->interleave = CFIDEV_INTERLEAVE_2;
200 
201 #ifdef SOMEONE_ACTUALLY_MAKES_THESE
202 		cfi->device_type = CFI_DEVICETYPE_X32;
203 		if (cp->probe_chip(map, 0, NULL, cfi))
204 			return 1;
205 #endif
206 		cfi->device_type = CFI_DEVICETYPE_X16;
207 		if (cp->probe_chip(map, 0, NULL, cfi))
208 			return 1;
209 
210 		cfi->device_type = CFI_DEVICETYPE_X8;
211 		if (cp->probe_chip(map, 0, NULL, cfi))
212 			return 1;
213 #endif /* CFIDEV_INTERLEAVE_2 */
214 #ifdef CFIDEV_INTERLEAVE_4
215 		cfi->interleave = CFIDEV_INTERLEAVE_4;
216 
217 #ifdef SOMEONE_ACTUALLY_MAKES_THESE
218 		cfi->device_type = CFI_DEVICETYPE_X32;
219 		if (cp->probe_chip(map, 0, NULL, cfi))
220 			return 1;
221 #endif
222 		cfi->device_type = CFI_DEVICETYPE_X16;
223 		if (cp->probe_chip(map, 0, NULL, cfi))
224 			return 1;
225 
226 		cfi->device_type = CFI_DEVICETYPE_X8;
227 		if (cp->probe_chip(map, 0, NULL, cfi))
228 			return 1;
229 #endif /* CFIDEV_INTERLEAVE_4 */
230 		break;
231 #endif /* CFIDEV_BUSWIDTH_4 */
232 
233 #ifdef CFIDEV_BUSWIDTH_8
234 	case CFIDEV_BUSWIDTH_8:
235 #if defined(CFIDEV_INTERLEAVE_2) && defined(SOMEONE_ACTUALLY_MAKES_THESE)
236                 cfi->interleave = CFIDEV_INTERLEAVE_2;
237 
238                 cfi->device_type = CFI_DEVICETYPE_X32;
239 		if (cp->probe_chip(map, 0, NULL, cfi))
240 			return 1;
241 #endif /* CFIDEV_INTERLEAVE_2 */
242 #ifdef CFIDEV_INTERLEAVE_4
243 		cfi->interleave = CFIDEV_INTERLEAVE_4;
244 
245 #ifdef SOMEONE_ACTUALLY_MAKES_THESE
246 		cfi->device_type = CFI_DEVICETYPE_X32;
247 		if (cp->probe_chip(map, 0, NULL, cfi))
248 			return 1;
249 #endif
250 		cfi->device_type = CFI_DEVICETYPE_X16;
251 		if (cp->probe_chip(map, 0, NULL, cfi))
252 			return 1;
253 #endif /* CFIDEV_INTERLEAVE_4 */
254 #ifdef CFIDEV_INTERLEAVE_8
255 		cfi->interleave = CFIDEV_INTERLEAVE_8;
256 
257 		cfi->device_type = CFI_DEVICETYPE_X16;
258 		if (cp->probe_chip(map, 0, NULL, cfi))
259 			return 1;
260 
261 		cfi->device_type = CFI_DEVICETYPE_X8;
262 		if (cp->probe_chip(map, 0, NULL, cfi))
263 			return 1;
264 #endif /* CFIDEV_INTERLEAVE_8 */
265 		break;
266 #endif /* CFIDEV_BUSWIDTH_8 */
267 
268 	default:
269 		printk(KERN_WARNING "genprobe_new_chip called with unsupported buswidth %d\n", map->buswidth);
270 		return 0;
271 	}
272 	return 0;
273 }
274 
275 
276 typedef struct mtd_info *cfi_cmdset_fn_t(struct map_info *, int);
277 
278 extern cfi_cmdset_fn_t cfi_cmdset_0001;
279 extern cfi_cmdset_fn_t cfi_cmdset_0002;
280 extern cfi_cmdset_fn_t cfi_cmdset_0020;
281 
cfi_cmdset_unknown(struct map_info * map,int primary)282 static inline struct mtd_info *cfi_cmdset_unknown(struct map_info *map,
283 						  int primary)
284 {
285 	struct cfi_private *cfi = map->fldrv_priv;
286 	__u16 type = primary?cfi->cfiq->P_ID:cfi->cfiq->A_ID;
287 #if defined(CONFIG_MODULES) && defined(HAVE_INTER_MODULE)
288 	char probename[32];
289 	cfi_cmdset_fn_t *probe_function;
290 
291 	sprintf(probename, "cfi_cmdset_%4.4X", type);
292 
293 	probe_function = inter_module_get_request(probename, probename);
294 
295 	if (probe_function) {
296 		struct mtd_info *mtd;
297 
298 		mtd = (*probe_function)(map, primary);
299 		/* If it was happy, it'll have increased its own use count */
300 		inter_module_put(probename);
301 		return mtd;
302 	}
303 #endif
304 	printk(KERN_NOTICE "Support for command set %04X not present\n",
305 	       type);
306 
307 	return NULL;
308 }
309 
check_cmd_set(struct map_info * map,int primary)310 static struct mtd_info *check_cmd_set(struct map_info *map, int primary)
311 {
312 	struct cfi_private *cfi = map->fldrv_priv;
313 	__u16 type = primary?cfi->cfiq->P_ID:cfi->cfiq->A_ID;
314 
315 	if (type == P_ID_NONE || type == P_ID_RESERVED)
316 		return NULL;
317 
318 	switch(type){
319 		/* Urgh. Ifdefs. The version with weak symbols was
320 		 * _much_ nicer. Shame it didn't seem to work on
321 		 * anything but x86, really.
322 		 * But we can't rely in inter_module_get() because
323 		 * that'd mean we depend on link order.
324 		 */
325 #ifdef CONFIG_MTD_CFI_INTELEXT
326 	case 0x0001:
327 	case 0x0003:
328 		return cfi_cmdset_0001(map, primary);
329 #endif
330 #ifdef CONFIG_MTD_CFI_AMDSTD
331 	case 0x0002:
332 		return cfi_cmdset_0002(map, primary);
333 #endif
334 #ifdef CONFIG_MTD_CFI_STAA
335         case 0x0020:
336 		return cfi_cmdset_0020(map, primary);
337 #endif
338 	}
339 
340 	return cfi_cmdset_unknown(map, primary);
341 }
342 
343 MODULE_LICENSE("GPL");
344 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
345 MODULE_DESCRIPTION("Helper routines for flash chip probe code");
346