summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/chips/gen_probe.c
blob: 4d4f978410161e63ed3a72e448fce6959d799ddf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
/*
 * Routines common to all CFI-type probes.
 * (C) 2001-2003 Red Hat, Inc.
 * GPL'd
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/cfi.h>
#include <linux/mtd/gen_probe.h>

static struct mtd_info *check_cmd_set(struct map_info *, int);
static struct cfi_private *genprobe_ident_chips(struct map_info *map,
						struct chip_probe *cp);
static int genprobe_new_chip(struct map_info *map, struct chip_probe *cp,
			     struct cfi_private *cfi);

struct mtd_info *mtd_do_chip_probe(struct map_info *map, struct chip_probe *cp)
{
	struct mtd_info *mtd;
	struct cfi_private *cfi;

	/* First probe the map to see if we have CFI stuff there. */
	cfi = genprobe_ident_chips(map, cp);

	if (!cfi)
		return NULL;

	map->fldrv_priv = cfi;
	/* OK we liked it. Now find a driver for the command set it talks */

	mtd = check_cmd_set(map, 1); /* First the primary cmdset */
	if (!mtd)
		mtd = check_cmd_set(map, 0); /* Then the secondary */

	if (mtd) {
		if (mtd->size > map->size) {
			printk(KERN_WARNING "Reducing visibility of %ldKiB chip to %ldKiB\n",
			       (unsigned long)mtd->size >> 10,
			       (unsigned long)map->size >> 10);
			mtd->size = map->size;
		}
		return mtd;
	}

	printk(KERN_WARNING"gen_probe: No supported Vendor Command Set found\n");

	kfree(cfi->cfiq);
	kfree(cfi);
	map->fldrv_priv = NULL;
	return NULL;
}
EXPORT_SYMBOL(mtd_do_chip_probe);


static struct cfi_private *genprobe_ident_chips(struct map_info *map, struct chip_probe *cp)
{
	struct cfi_private cfi;
	struct cfi_private *retcfi;
	unsigned long *chip_map;
	int max_chips;
	int i, j;

	memset(&cfi, 0, sizeof(cfi));

	/* Call the probetype-specific code with all permutations of
	   interleave and device type, etc. */
	if (!genprobe_new_chip(map, cp, &cfi)) {
		/* The probe didn't like it */
		pr_debug("%s: Found no %s device at location zero\n",
			 cp->name, map->name);
		return NULL;
	}

#if 0 /* Let the CFI probe routine do this sanity check. The Intel and AMD
	 probe routines won't ever return a broken CFI structure anyway,
	 because they make them up themselves.
      */
	if (cfi.cfiq->NumEraseRegions == 0) {
		printk(KERN_WARNING "Number of erase regions is zero\n");
		kfree(cfi.cfiq);
		return NULL;
	}
#endif
	cfi.chipshift = cfi.cfiq->DevSize;

	if (cfi_interleave_is_1(&cfi)) {
		;
	} else if (cfi_interleave_is_2(&cfi)) {
		cfi.chipshift++;
	} else if (cfi_interleave_is_4((&cfi))) {
		cfi.chipshift += 2;
	} else if (cfi_interleave_is_8(&cfi)) {
		cfi.chipshift += 3;
	} else {
		BUG();
	}

	cfi.numchips = 1;

	/*
	 * Allocate memory for bitmap of valid chips.
	 * Align bitmap storage size to full byte.
	 */
	max_chips = map->size >> cfi.chipshift;
	if (!max_chips) {
		printk(KERN_WARNING "NOR chip too large to fit in mapping. Attempting to cope...\n");
		max_chips = 1;
	}

	chip_map = bitmap_zalloc(max_chips, GFP_KERNEL);
	if (!chip_map) {
		kfree(cfi.cfiq);
		return NULL;
	}

	set_bit(0, chip_map); /* Mark first chip valid */

	/*
	 * Now probe for other chips, checking sensibly for aliases while
	 * we're at it. The new_chip probe above should have let the first
	 * chip in read mode.
	 */

	for (i = 1; i < max_chips; i++) {
		cp->probe_chip(map, i << cfi.chipshift, chip_map, &cfi);
	}

	/*
	 * Now allocate the space for the structures we need to return to
	 * our caller, and copy the appropriate data into them.
	 */

	retcfi = kmalloc(struct_size(retcfi, chips, cfi.numchips), GFP_KERNEL);

	if (!retcfi) {
		kfree(cfi.cfiq);
		bitmap_free(chip_map);
		return NULL;
	}

	memcpy(retcfi, &cfi, sizeof(cfi));
	memset(&retcfi->chips[0], 0, sizeof(struct flchip) * cfi.numchips);

	for (i = 0, j = 0; (j < cfi.numchips) && (i < max_chips); i++) {
		if(test_bit(i, chip_map)) {
			struct flchip *pchip = &retcfi->chips[j++];

			pchip->start = (i << cfi.chipshift);
			pchip->state = FL_READY;
			init_waitqueue_head(&pchip->wq);
			mutex_init(&pchip->mutex);
		}
	}

	bitmap_free(chip_map);
	return retcfi;
}


static int genprobe_new_chip(struct map_info *map, struct chip_probe *cp,
			     struct cfi_private *cfi)
{
	int min_chips = (map_bankwidth(map)/4?:1); /* At most 4-bytes wide. */
	int max_chips = map_bankwidth(map); /* And minimum 1 */
	int nr_chips, type;

	for (nr_chips = max_chips; nr_chips >= min_chips; nr_chips >>= 1) {

		if (!cfi_interleave_supported(nr_chips))
		    continue;

		cfi->interleave = nr_chips;

		/* Minimum device size. Don't look for one 8-bit device
		   in a 16-bit bus, etc. */
		type = map_bankwidth(map) / nr_chips;

		for (; type <= CFI_DEVICETYPE_X32; type<<=1) {
			cfi->device_type = type;

			if (cp->probe_chip(map, 0, NULL, cfi))
				return 1;
		}
	}
	return 0;
}

typedef struct mtd_info *cfi_cmdset_fn_t(struct map_info *, int);

extern cfi_cmdset_fn_t cfi_cmdset_0001;
extern cfi_cmdset_fn_t cfi_cmdset_0002;
extern cfi_cmdset_fn_t cfi_cmdset_0020;

static inline struct mtd_info *cfi_cmdset_unknown(struct map_info *map,
						  int primary)
{
	struct cfi_private *cfi = map->fldrv_priv;
	__u16 type = primary?cfi->cfiq->P_ID:cfi->cfiq->A_ID;
#ifdef CONFIG_MODULES
	cfi_cmdset_fn_t *probe_function;
	char *probename;

	probename = kasprintf(GFP_KERNEL, "cfi_cmdset_%4.4X", type);
	if (!probename)
		return NULL;

	probe_function = __symbol_get(probename);
	if (!probe_function) {
		request_module("cfi_cmdset_%4.4X", type);
		probe_function = __symbol_get(probename);
	}
	kfree(probename);

	if (probe_function) {
		struct mtd_info *mtd;

		mtd = (*probe_function)(map, primary);
		/* If it was happy, it'll have increased its own use count */
		symbol_put_addr(probe_function);
		return mtd;
	}
#endif
	printk(KERN_NOTICE "Support for command set %04X not present\n", type);

	return NULL;
}

static struct mtd_info *check_cmd_set(struct map_info *map, int primary)
{
	struct cfi_private *cfi = map->fldrv_priv;
	__u16 type = primary?cfi->cfiq->P_ID:cfi->cfiq->A_ID;

	if (type == P_ID_NONE || type == P_ID_RESERVED)
		return NULL;

	switch(type){
		/* We need these for the !CONFIG_MODULES case,
		   because symbol_get() doesn't work there */
#ifdef CONFIG_MTD_CFI_INTELEXT
	case P_ID_INTEL_EXT:
	case P_ID_INTEL_STD:
	case P_ID_INTEL_PERFORMANCE:
		return cfi_cmdset_0001(map, primary);
#endif
#ifdef CONFIG_MTD_CFI_AMDSTD
	case P_ID_AMD_STD:
	case P_ID_SST_OLD:
	case P_ID_WINBOND:
		return cfi_cmdset_0002(map, primary);
#endif
#ifdef CONFIG_MTD_CFI_STAA
        case P_ID_ST_ADV:
		return cfi_cmdset_0020(map, primary);
#endif
	default:
		return cfi_cmdset_unknown(map, primary);
	}
}

MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_DESCRIPTION("Helper routines for flash chip probe code");