aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/mtd/chips/cfi_probe.c
blob: cf750038ce6af9645df83ff320a35200c6598168 (plain) (tree)
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
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445




























































































































































































































































































































































































































































                                                                                                                                    
/* 
   Common Flash Interface probe code.
   (C) 2000 Red Hat. GPL'd.
   $Id: cfi_probe.c,v 1.83 2004/11/16 18:19:02 nico Exp $
*/

#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/io.h>
#include <asm/byteorder.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/interrupt.h>

#include <linux/mtd/xip.h>
#include <linux/mtd/map.h>
#include <linux/mtd/cfi.h>
#include <linux/mtd/gen_probe.h>

//#define DEBUG_CFI 

#ifdef DEBUG_CFI
static void print_cfi_ident(struct cfi_ident *);
#endif

static int cfi_probe_chip(struct map_info *map, __u32 base,
			  unsigned long *chip_map, struct cfi_private *cfi);
static int cfi_chip_setup(struct map_info *map, struct cfi_private *cfi);

struct mtd_info *cfi_probe(struct map_info *map);

#ifdef CONFIG_MTD_XIP

/* only needed for short periods, so this is rather simple */
#define xip_disable()	local_irq_disable()

#define xip_allowed(base, map) \
do { \
	(void) map_read(map, base); \
	asm volatile (".rep 8; nop; .endr"); \
	local_irq_enable(); \
} while (0)

#define xip_enable(base, map, cfi) \
do { \
	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL); \
	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL); \
	xip_allowed(base, map); \
} while (0)

#define xip_disable_qry(base, map, cfi) \
do { \
	xip_disable(); \
	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL); \
	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL); \
	cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL); \
} while (0)

#else

#define xip_disable()			do { } while (0)
#define xip_allowed(base, map)		do { } while (0)
#define xip_enable(base, map, cfi)	do { } while (0)
#define xip_disable_qry(base, map, cfi) do { } while (0)

#endif

/* check for QRY.
   in: interleave,type,mode
   ret: table index, <0 for error
 */
static int __xipram qry_present(struct map_info *map, __u32 base,
				struct cfi_private *cfi)
{
	int osf = cfi->interleave * cfi->device_type;	// scale factor
	map_word val[3];
	map_word qry[3];

	qry[0] = cfi_build_cmd('Q', map, cfi);
	qry[1] = cfi_build_cmd('R', map, cfi);
	qry[2] = cfi_build_cmd('Y', map, cfi);

	val[0] = map_read(map, base + osf*0x10);
	val[1] = map_read(map, base + osf*0x11);
	val[2] = map_read(map, base + osf*0x12);

	if (!map_word_equal(map, qry[0], val[0]))
		return 0;

	if (!map_word_equal(map, qry[1], val[1]))
		return 0;

	if (!map_word_equal(map, qry[2], val[2]))
		return 0;

	return 1; 	// "QRY" found
}

static int __xipram cfi_probe_chip(struct map_info *map, __u32 base,
				   unsigned long *chip_map, struct cfi_private *cfi)
{
	int i;
	
	if ((base + 0) >= map->size) {
		printk(KERN_NOTICE
			"Probe at base[0x00](0x%08lx) past the end of the map(0x%08lx)\n",
			(unsigned long)base, map->size -1);
		return 0;
	}
	if ((base + 0xff) >= map->size) {
		printk(KERN_NOTICE
			"Probe at base[0x55](0x%08lx) past the end of the map(0x%08lx)\n",
			(unsigned long)base + 0x55, map->size -1);
		return 0;
	}

	xip_disable();
	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
	cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);

	if (!qry_present(map,base,cfi)) {
		xip_enable(base, map, cfi);
		return 0;
	}

	if (!cfi->numchips) {
		/* This is the first time we're called. Set up the CFI 
		   stuff accordingly and return */
		return cfi_chip_setup(map, cfi);
	}

	/* Check each previous chip to see if it's an alias */
 	for (i=0; i < (base >> cfi->chipshift); i++) {
 		unsigned long start;
 		if(!test_bit(i, chip_map)) {
			/* Skip location; no valid chip at this address */
 			continue; 
 		}
 		start = i << cfi->chipshift;
		/* This chip should be in read mode if it's one
		   we've already touched. */
		if (qry_present(map, start, cfi)) {
			/* Eep. This chip also had the QRY marker. 
			 * Is it an alias for the new one? */
			cfi_send_gen_cmd(0xF0, 0, start, map, cfi, cfi->device_type, NULL);
			cfi_send_gen_cmd(0xFF, 0, start, map, cfi, cfi->device_type, NULL);

			/* If the QRY marker goes away, it's an alias */
			if (!qry_present(map, start, cfi)) {
				xip_allowed(base, map);
				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
				       map->name, base, start);
				return 0;
			}
			/* Yes, it's actually got QRY for data. Most 
			 * unfortunate. Stick the new chip in read mode
			 * too and if it's the same, assume it's an alias. */
			/* FIXME: Use other modes to do a proper check */
			cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
			cfi_send_gen_cmd(0xFF, 0, start, map, cfi, cfi->device_type, NULL);
			
			if (qry_present(map, base, cfi)) {
				xip_allowed(base, map);
				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
				       map->name, base, start);
				return 0;
			}
		}
	}
	
	/* OK, if we got to here, then none of the previous chips appear to
	   be aliases for the current one. */
	set_bit((base >> cfi->chipshift), chip_map); /* Update chip map */
	cfi->numchips++;
	
	/* Put it back into Read Mode */
	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
	xip_allowed(base, map);

	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
	       map->name, cfi->interleave, cfi->device_type*8, base,
	       map->bankwidth*8);
	
	return 1;
}

static int __xipram cfi_chip_setup(struct map_info *map, 
				   struct cfi_private *cfi)
{
	int ofs_factor = cfi->interleave*cfi->device_type;
	__u32 base = 0;
	int num_erase_regions = cfi_read_query(map, base + (0x10 + 28)*ofs_factor);
	int i;

	xip_enable(base, map, cfi);
#ifdef DEBUG_CFI
	printk("Number of erase regions: %d\n", num_erase_regions);
#endif
	if (!num_erase_regions)
		return 0;

	cfi->cfiq = kmalloc(sizeof(struct cfi_ident) + num_erase_regions * 4, GFP_KERNEL);
	if (!cfi->cfiq) {
		printk(KERN_WARNING "%s: kmalloc failed for CFI ident structure\n", map->name);
		return 0;
	}
	
	memset(cfi->cfiq,0,sizeof(struct cfi_ident));	
	
	cfi->cfi_mode = CFI_MODE_CFI;
	
	/* Read the CFI info structure */
	xip_disable_qry(base, map, cfi);
	for (i=0; i<(sizeof(struct cfi_ident) + num_erase_regions * 4); i++)
		((unsigned char *)cfi->cfiq)[i] = cfi_read_query(map,base + (0x10 + i)*ofs_factor);

	/* Note we put the device back into Read Mode BEFORE going into Auto
	 * Select Mode, as some devices support nesting of modes, others
	 * don't. This way should always work.
	 * On cmdset 0001 the writes of 0xaa and 0x55 are not needed, and
	 * so should be treated as nops or illegal (and so put the device
	 * back into Read Mode, which is a nop in this case).
	 */
	cfi_send_gen_cmd(0xf0,     0, base, map, cfi, cfi->device_type, NULL);
	cfi_send_gen_cmd(0xaa, 0x555, base, map, cfi, cfi->device_type, NULL);
	cfi_send_gen_cmd(0x55, 0x2aa, base, map, cfi, cfi->device_type, NULL);
	cfi_send_gen_cmd(0x90, 0x555, base, map, cfi, cfi->device_type, NULL);
	cfi->mfr = cfi_read_query(map, base);
	cfi->id = cfi_read_query(map, base + ofs_factor);    

	/* Put it back into Read Mode */
	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
	/* ... even if it's an Intel chip */
	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
	xip_allowed(base, map);

	/* Do any necessary byteswapping */
	cfi->cfiq->P_ID = le16_to_cpu(cfi->cfiq->P_ID);

	cfi->cfiq->P_ADR = le16_to_cpu(cfi->cfiq->P_ADR);
	cfi->cfiq->A_ID = le16_to_cpu(cfi->cfiq->A_ID);
	cfi->cfiq->A_ADR = le16_to_cpu(cfi->cfiq->A_ADR);
	cfi->cfiq->InterfaceDesc = le16_to_cpu(cfi->cfiq->InterfaceDesc);
	cfi->cfiq->MaxBufWriteSize = le16_to_cpu(cfi->cfiq->MaxBufWriteSize);

#ifdef DEBUG_CFI
	/* Dump the information therein */
	print_cfi_ident(cfi->cfiq);
#endif

	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
		cfi->cfiq->EraseRegionInfo[i] = le32_to_cpu(cfi->cfiq->EraseRegionInfo[i]);
		
#ifdef DEBUG_CFI		
		printk("  Erase Region #%d: BlockSize 0x%4.4X bytes, %d blocks\n",
		       i, (cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff, 
		       (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1);
#endif
	}

	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
	       map->name, cfi->interleave, cfi->device_type*8, base,
	       map->bankwidth*8);

	return 1;
}

#ifdef DEBUG_CFI
static char *vendorname(__u16 vendor) 
{
	switch (vendor) {
	case P_ID_NONE:
		return "None";
		
	case P_ID_INTEL_EXT:
		return "Intel/Sharp Extended";
		
	case P_ID_AMD_STD:
		return "AMD/Fujitsu Standard";
		
	case P_ID_INTEL_STD:
		return "Intel/Sharp Standard";
		
	case P_ID_AMD_EXT:
		return "AMD/Fujitsu Extended";

	case P_ID_WINBOND:
		return "Winbond Standard";
		
	case P_ID_ST_ADV:
		return "ST Advanced";

	case P_ID_MITSUBISHI_STD:
		return "Mitsubishi Standard";
		
	case P_ID_MITSUBISHI_EXT:
		return "Mitsubishi Extended";

	case P_ID_SST_PAGE:
		return "SST Page Write";

	case P_ID_INTEL_PERFORMANCE:
		return "Intel Performance Code";
		
	case P_ID_INTEL_DATA:
		return "Intel Data";
		
	case P_ID_RESERVED:
		return "Not Allowed / Reserved for Future Use";
		
	default:
		return "Unknown";
	}
}


static void print_cfi_ident(struct cfi_ident *cfip)
{
#if 0
	if (cfip->qry[0] != 'Q' || cfip->qry[1] != 'R' || cfip->qry[2] != 'Y') {
		printk("Invalid CFI ident structure.\n");
		return;
	}	
#endif		
	printk("Primary Vendor Command Set: %4.4X (%s)\n", cfip->P_ID, vendorname(cfip->P_ID));
	if (cfip->P_ADR)
		printk("Primary Algorithm Table at %4.4X\n", cfip->P_ADR);
	else
		printk("No Primary Algorithm Table\n");
	
	printk("Alternative Vendor Command Set: %4.4X (%s)\n", cfip->A_ID, vendorname(cfip->A_ID));
	if (cfip->A_ADR)
		printk("Alternate Algorithm Table at %4.4X\n", cfip->A_ADR);
	else
		printk("No Alternate Algorithm Table\n");
		
		
	printk("Vcc Minimum: %2d.%d V\n", cfip->VccMin >> 4, cfip->VccMin & 0xf);
	printk("Vcc Maximum: %2d.%d V\n", cfip->VccMax >> 4, cfip->VccMax & 0xf);
	if (cfip->VppMin) {
		printk("Vpp Minimum: %2d.%d V\n", cfip->VppMin >> 4, cfip->VppMin & 0xf);
		printk("Vpp Maximum: %2d.%d V\n", cfip->VppMax >> 4, cfip->VppMax & 0xf);
	}
	else
		printk("No Vpp line\n");
	
	printk("Typical byte/word write timeout: %d µs\n", 1<<cfip->WordWriteTimeoutTyp);
	printk("Maximum byte/word write timeout: %d µs\n", (1<<cfip->WordWriteTimeoutMax) * (1<<cfip->WordWriteTimeoutTyp));
	
	if (cfip->BufWriteTimeoutTyp || cfip->BufWriteTimeoutMax) {
		printk("Typical full buffer write timeout: %d µs\n", 1<<cfip->BufWriteTimeoutTyp);
		printk("Maximum full buffer write timeout: %d µs\n", (1<<cfip->BufWriteTimeoutMax) * (1<<cfip->BufWriteTimeoutTyp));
	}
	else
		printk("Full buffer write not supported\n");
	
	printk("Typical block erase timeout: %d ms\n", 1<<cfip->BlockEraseTimeoutTyp);
	printk("Maximum block erase timeout: %d ms\n", (1<<cfip->BlockEraseTimeoutMax) * (1<<cfip->BlockEraseTimeoutTyp));
	if (cfip->ChipEraseTimeoutTyp || cfip->ChipEraseTimeoutMax) {
		printk("Typical chip erase timeout: %d ms\n", 1<<cfip->ChipEraseTimeoutTyp); 
		printk("Maximum chip erase timeout: %d ms\n", (1<<cfip->ChipEraseTimeoutMax) * (1<<cfip->ChipEraseTimeoutTyp));
	}
	else
		printk("Chip erase not supported\n");
	
	printk("Device size: 0x%X bytes (%d MiB)\n", 1 << cfip->DevSize, 1<< (cfip->DevSize - 20));
	printk("Flash Device Interface description: 0x%4.4X\n", cfip->InterfaceDesc);
	switch(cfip->InterfaceDesc) {
	case 0:
		printk("  - x8-only asynchronous interface\n");
		break;
		
	case 1:
		printk("  - x16-only asynchronous interface\n");
		break;
		
	case 2:
		printk("  - supports x8 and x16 via BYTE# with asynchronous interface\n");
		break;
		
	case 3:
		printk("  - x32-only asynchronous interface\n");
		break;
		
	case 4:
		printk("  - supports x16 and x32 via Word# with asynchronous interface\n");
		break;
		
	case 65535:
		printk("  - Not Allowed / Reserved\n");
		break;
		
	default:
		printk("  - Unknown\n");
		break;
	}
	
	printk("Max. bytes in buffer write: 0x%x\n", 1<< cfip->MaxBufWriteSize);
	printk("Number of Erase Block Regions: %d\n", cfip->NumEraseRegions);
	
}
#endif /* DEBUG_CFI */

static struct chip_probe cfi_chip_probe = {
	.name		= "CFI",
	.probe_chip	= cfi_probe_chip
};

struct mtd_info *cfi_probe(struct map_info *map)
{
	/*
	 * Just use the generic probe stuff to call our CFI-specific
	 * chip_probe routine in all the possible permutations, etc.
	 */
	return mtd_do_chip_probe(map, &cfi_chip_probe);
}

static struct mtd_chip_driver cfi_chipdrv = {
	.probe		= cfi_probe,
	.name		= "cfi_probe",
	.module		= THIS_MODULE
};

int __init cfi_probe_init(void)
{
	register_mtd_chip_driver(&cfi_chipdrv);
	return 0;
}

static void __exit cfi_probe_exit(void)
{
	unregister_mtd_chip_driver(&cfi_chipdrv);
}

module_init(cfi_probe_init);
module_exit(cfi_probe_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org> et al.");
MODULE_DESCRIPTION("Probe code for CFI-compliant flash chips");