xref: /openbmc/linux/drivers/mtd/chips/cfi_probe.c (revision e15a5365)
1 /*
2    Common Flash Interface probe code.
3    (C) 2000 Red Hat. GPL'd.
4 */
5 
6 #include <linux/module.h>
7 #include <linux/types.h>
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <asm/io.h>
11 #include <asm/byteorder.h>
12 #include <linux/errno.h>
13 #include <linux/slab.h>
14 #include <linux/interrupt.h>
15 
16 #include <linux/mtd/xip.h>
17 #include <linux/mtd/map.h>
18 #include <linux/mtd/cfi.h>
19 #include <linux/mtd/gen_probe.h>
20 
21 //#define DEBUG_CFI
22 
23 #ifdef DEBUG_CFI
24 static void print_cfi_ident(struct cfi_ident *);
25 #endif
26 
27 static int cfi_probe_chip(struct map_info *map, __u32 base,
28 			  unsigned long *chip_map, struct cfi_private *cfi);
29 static int cfi_chip_setup(struct map_info *map, struct cfi_private *cfi);
30 
31 struct mtd_info *cfi_probe(struct map_info *map);
32 
33 #ifdef CONFIG_MTD_XIP
34 
35 /* only needed for short periods, so this is rather simple */
36 #define xip_disable()	local_irq_disable()
37 
38 #define xip_allowed(base, map) \
39 do { \
40 	(void) map_read(map, base); \
41 	xip_iprefetch(); \
42 	local_irq_enable(); \
43 } while (0)
44 
45 #define xip_enable(base, map, cfi) \
46 do { \
47 	cfi_qry_mode_off(base, map, cfi);		\
48 	xip_allowed(base, map); \
49 } while (0)
50 
51 #define xip_disable_qry(base, map, cfi) \
52 do { \
53 	xip_disable(); \
54 	cfi_qry_mode_on(base, map, cfi); \
55 } while (0)
56 
57 #else
58 
59 #define xip_disable()			do { } while (0)
60 #define xip_allowed(base, map)		do { } while (0)
61 #define xip_enable(base, map, cfi)	do { } while (0)
62 #define xip_disable_qry(base, map, cfi) do { } while (0)
63 
64 #endif
65 
66 /*
67  * This fixup occurs immediately after reading the CFI structure and can affect
68  * the number of chips detected, unlike cfi_fixup, which occurs after an
69  * mtd_info structure has been created for the chip.
70  */
71 struct cfi_early_fixup {
72 	uint16_t mfr;
73 	uint16_t id;
74 	void (*fixup)(struct cfi_private *cfi);
75 };
76 
77 static void cfi_early_fixup(struct cfi_private *cfi,
78 			    const struct cfi_early_fixup *fixups)
79 {
80 	const struct cfi_early_fixup *f;
81 
82 	for (f = fixups; f->fixup; f++) {
83 		if (((f->mfr == CFI_MFR_ANY) || (f->mfr == cfi->mfr)) &&
84 		    ((f->id == CFI_ID_ANY) || (f->id == cfi->id))) {
85 			f->fixup(cfi);
86 		}
87 	}
88 }
89 
90 /* check for QRY.
91    in: interleave,type,mode
92    ret: table index, <0 for error
93  */
94 
95 static int __xipram cfi_probe_chip(struct map_info *map, __u32 base,
96 				   unsigned long *chip_map, struct cfi_private *cfi)
97 {
98 	int i;
99 
100 	if ((base + 0) >= map->size) {
101 		printk(KERN_NOTICE
102 			"Probe at base[0x00](0x%08lx) past the end of the map(0x%08lx)\n",
103 			(unsigned long)base, map->size -1);
104 		return 0;
105 	}
106 	if ((base + 0xff) >= map->size) {
107 		printk(KERN_NOTICE
108 			"Probe at base[0x55](0x%08lx) past the end of the map(0x%08lx)\n",
109 			(unsigned long)base + 0x55, map->size -1);
110 		return 0;
111 	}
112 
113 	xip_disable();
114 	if (!cfi_qry_mode_on(base, map, cfi)) {
115 		xip_enable(base, map, cfi);
116 		return 0;
117 	}
118 
119 	if (!cfi->numchips) {
120 		/* This is the first time we're called. Set up the CFI
121 		   stuff accordingly and return */
122 		return cfi_chip_setup(map, cfi);
123 	}
124 
125 	/* Check each previous chip to see if it's an alias */
126  	for (i=0; i < (base >> cfi->chipshift); i++) {
127  		unsigned long start;
128  		if(!test_bit(i, chip_map)) {
129 			/* Skip location; no valid chip at this address */
130  			continue;
131  		}
132  		start = i << cfi->chipshift;
133 		/* This chip should be in read mode if it's one
134 		   we've already touched. */
135 		if (cfi_qry_present(map, start, cfi)) {
136 			/* Eep. This chip also had the QRY marker.
137 			 * Is it an alias for the new one? */
138 			cfi_qry_mode_off(start, map, cfi);
139 
140 			/* If the QRY marker goes away, it's an alias */
141 			if (!cfi_qry_present(map, start, cfi)) {
142 				xip_allowed(base, map);
143 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
144 				       map->name, base, start);
145 				return 0;
146 			}
147 			/* Yes, it's actually got QRY for data. Most
148 			 * unfortunate. Stick the new chip in read mode
149 			 * too and if it's the same, assume it's an alias. */
150 			/* FIXME: Use other modes to do a proper check */
151 			cfi_qry_mode_off(base, map, cfi);
152 
153 			if (cfi_qry_present(map, base, cfi)) {
154 				xip_allowed(base, map);
155 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
156 				       map->name, base, start);
157 				return 0;
158 			}
159 		}
160 	}
161 
162 	/* OK, if we got to here, then none of the previous chips appear to
163 	   be aliases for the current one. */
164 	set_bit((base >> cfi->chipshift), chip_map); /* Update chip map */
165 	cfi->numchips++;
166 
167 	/* Put it back into Read Mode */
168 	cfi_qry_mode_off(base, map, cfi);
169 	xip_allowed(base, map);
170 
171 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
172 	       map->name, cfi->interleave, cfi->device_type*8, base,
173 	       map->bankwidth*8);
174 
175 	return 1;
176 }
177 
178 static void fixup_s70gl02gs_chips(struct cfi_private *cfi)
179 {
180 	/*
181 	 * S70GL02GS flash reports a single 256 MiB chip, but is really made up
182 	 * of two 128 MiB chips with 1024 sectors each.
183 	 */
184 	cfi->cfiq->DevSize = 27;
185 	cfi->cfiq->EraseRegionInfo[0] = 0x20003ff;
186 	pr_warn("Bad S70GL02GS CFI data; adjust to detect 2 chips\n");
187 }
188 
189 static const struct cfi_early_fixup cfi_early_fixup_table[] = {
190 	{ CFI_MFR_AMD, 0x4801, fixup_s70gl02gs_chips },
191 	{ },
192 };
193 
194 static int __xipram cfi_chip_setup(struct map_info *map,
195 				   struct cfi_private *cfi)
196 {
197 	int ofs_factor = cfi->interleave*cfi->device_type;
198 	__u32 base = 0;
199 	int num_erase_regions = cfi_read_query(map, base + (0x10 + 28)*ofs_factor);
200 	int i;
201 	int addr_unlock1 = 0x555, addr_unlock2 = 0x2AA;
202 
203 	xip_enable(base, map, cfi);
204 #ifdef DEBUG_CFI
205 	printk("Number of erase regions: %d\n", num_erase_regions);
206 #endif
207 	if (!num_erase_regions)
208 		return 0;
209 
210 	cfi->cfiq = kmalloc(sizeof(struct cfi_ident) + num_erase_regions * 4, GFP_KERNEL);
211 	if (!cfi->cfiq)
212 		return 0;
213 
214 	memset(cfi->cfiq,0,sizeof(struct cfi_ident));
215 
216 	cfi->cfi_mode = CFI_MODE_CFI;
217 
218 	cfi->sector_erase_cmd = CMD(0x30);
219 
220 	/* Read the CFI info structure */
221 	xip_disable_qry(base, map, cfi);
222 	for (i=0; i<(sizeof(struct cfi_ident) + num_erase_regions * 4); i++)
223 		((unsigned char *)cfi->cfiq)[i] = cfi_read_query(map,base + (0x10 + i)*ofs_factor);
224 
225 	/* Do any necessary byteswapping */
226 	cfi->cfiq->P_ID = le16_to_cpu(cfi->cfiq->P_ID);
227 
228 	cfi->cfiq->P_ADR = le16_to_cpu(cfi->cfiq->P_ADR);
229 	cfi->cfiq->A_ID = le16_to_cpu(cfi->cfiq->A_ID);
230 	cfi->cfiq->A_ADR = le16_to_cpu(cfi->cfiq->A_ADR);
231 	cfi->cfiq->InterfaceDesc = le16_to_cpu(cfi->cfiq->InterfaceDesc);
232 	cfi->cfiq->MaxBufWriteSize = le16_to_cpu(cfi->cfiq->MaxBufWriteSize);
233 
234 #ifdef DEBUG_CFI
235 	/* Dump the information therein */
236 	print_cfi_ident(cfi->cfiq);
237 #endif
238 
239 	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
240 		cfi->cfiq->EraseRegionInfo[i] = le32_to_cpu(cfi->cfiq->EraseRegionInfo[i]);
241 
242 #ifdef DEBUG_CFI
243 		printk("  Erase Region #%d: BlockSize 0x%4.4X bytes, %d blocks\n",
244 		       i, (cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff,
245 		       (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1);
246 #endif
247 	}
248 
249 	if (cfi->cfiq->P_ID == P_ID_SST_OLD) {
250 		addr_unlock1 = 0x5555;
251 		addr_unlock2 = 0x2AAA;
252 	}
253 
254 	/*
255 	 * Note we put the device back into Read Mode BEFORE going into Auto
256 	 * Select Mode, as some devices support nesting of modes, others
257 	 * don't. This way should always work.
258 	 * On cmdset 0001 the writes of 0xaa and 0x55 are not needed, and
259 	 * so should be treated as nops or illegal (and so put the device
260 	 * back into Read Mode, which is a nop in this case).
261 	 */
262 	cfi_send_gen_cmd(0xf0,     0, base, map, cfi, cfi->device_type, NULL);
263 	cfi_send_gen_cmd(0xaa, addr_unlock1, base, map, cfi, cfi->device_type, NULL);
264 	cfi_send_gen_cmd(0x55, addr_unlock2, base, map, cfi, cfi->device_type, NULL);
265 	cfi_send_gen_cmd(0x90, addr_unlock1, base, map, cfi, cfi->device_type, NULL);
266 	cfi->mfr = cfi_read_query16(map, base);
267 	cfi->id = cfi_read_query16(map, base + ofs_factor);
268 
269 	/* Get AMD/Spansion extended JEDEC ID */
270 	if (cfi->mfr == CFI_MFR_AMD && (cfi->id & 0xff) == 0x7e)
271 		cfi->id = cfi_read_query(map, base + 0xe * ofs_factor) << 8 |
272 			  cfi_read_query(map, base + 0xf * ofs_factor);
273 
274 	/* Put it back into Read Mode */
275 	cfi_qry_mode_off(base, map, cfi);
276 	xip_allowed(base, map);
277 
278 	cfi_early_fixup(cfi, cfi_early_fixup_table);
279 
280 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank. Manufacturer ID %#08x Chip ID %#08x\n",
281 	       map->name, cfi->interleave, cfi->device_type*8, base,
282 	       map->bankwidth*8, cfi->mfr, cfi->id);
283 
284 	return 1;
285 }
286 
287 #ifdef DEBUG_CFI
288 static char *vendorname(__u16 vendor)
289 {
290 	switch (vendor) {
291 	case P_ID_NONE:
292 		return "None";
293 
294 	case P_ID_INTEL_EXT:
295 		return "Intel/Sharp Extended";
296 
297 	case P_ID_AMD_STD:
298 		return "AMD/Fujitsu Standard";
299 
300 	case P_ID_INTEL_STD:
301 		return "Intel/Sharp Standard";
302 
303 	case P_ID_AMD_EXT:
304 		return "AMD/Fujitsu Extended";
305 
306 	case P_ID_WINBOND:
307 		return "Winbond Standard";
308 
309 	case P_ID_ST_ADV:
310 		return "ST Advanced";
311 
312 	case P_ID_MITSUBISHI_STD:
313 		return "Mitsubishi Standard";
314 
315 	case P_ID_MITSUBISHI_EXT:
316 		return "Mitsubishi Extended";
317 
318 	case P_ID_SST_PAGE:
319 		return "SST Page Write";
320 
321 	case P_ID_SST_OLD:
322 		return "SST 39VF160x/39VF320x";
323 
324 	case P_ID_INTEL_PERFORMANCE:
325 		return "Intel Performance Code";
326 
327 	case P_ID_INTEL_DATA:
328 		return "Intel Data";
329 
330 	case P_ID_RESERVED:
331 		return "Not Allowed / Reserved for Future Use";
332 
333 	default:
334 		return "Unknown";
335 	}
336 }
337 
338 
339 static void print_cfi_ident(struct cfi_ident *cfip)
340 {
341 #if 0
342 	if (cfip->qry[0] != 'Q' || cfip->qry[1] != 'R' || cfip->qry[2] != 'Y') {
343 		printk("Invalid CFI ident structure.\n");
344 		return;
345 	}
346 #endif
347 	printk("Primary Vendor Command Set: %4.4X (%s)\n", cfip->P_ID, vendorname(cfip->P_ID));
348 	if (cfip->P_ADR)
349 		printk("Primary Algorithm Table at %4.4X\n", cfip->P_ADR);
350 	else
351 		printk("No Primary Algorithm Table\n");
352 
353 	printk("Alternative Vendor Command Set: %4.4X (%s)\n", cfip->A_ID, vendorname(cfip->A_ID));
354 	if (cfip->A_ADR)
355 		printk("Alternate Algorithm Table at %4.4X\n", cfip->A_ADR);
356 	else
357 		printk("No Alternate Algorithm Table\n");
358 
359 
360 	printk("Vcc Minimum: %2d.%d V\n", cfip->VccMin >> 4, cfip->VccMin & 0xf);
361 	printk("Vcc Maximum: %2d.%d V\n", cfip->VccMax >> 4, cfip->VccMax & 0xf);
362 	if (cfip->VppMin) {
363 		printk("Vpp Minimum: %2d.%d V\n", cfip->VppMin >> 4, cfip->VppMin & 0xf);
364 		printk("Vpp Maximum: %2d.%d V\n", cfip->VppMax >> 4, cfip->VppMax & 0xf);
365 	}
366 	else
367 		printk("No Vpp line\n");
368 
369 	printk("Typical byte/word write timeout: %d µs\n", 1<<cfip->WordWriteTimeoutTyp);
370 	printk("Maximum byte/word write timeout: %d µs\n", (1<<cfip->WordWriteTimeoutMax) * (1<<cfip->WordWriteTimeoutTyp));
371 
372 	if (cfip->BufWriteTimeoutTyp || cfip->BufWriteTimeoutMax) {
373 		printk("Typical full buffer write timeout: %d µs\n", 1<<cfip->BufWriteTimeoutTyp);
374 		printk("Maximum full buffer write timeout: %d µs\n", (1<<cfip->BufWriteTimeoutMax) * (1<<cfip->BufWriteTimeoutTyp));
375 	}
376 	else
377 		printk("Full buffer write not supported\n");
378 
379 	printk("Typical block erase timeout: %d ms\n", 1<<cfip->BlockEraseTimeoutTyp);
380 	printk("Maximum block erase timeout: %d ms\n", (1<<cfip->BlockEraseTimeoutMax) * (1<<cfip->BlockEraseTimeoutTyp));
381 	if (cfip->ChipEraseTimeoutTyp || cfip->ChipEraseTimeoutMax) {
382 		printk("Typical chip erase timeout: %d ms\n", 1<<cfip->ChipEraseTimeoutTyp);
383 		printk("Maximum chip erase timeout: %d ms\n", (1<<cfip->ChipEraseTimeoutMax) * (1<<cfip->ChipEraseTimeoutTyp));
384 	}
385 	else
386 		printk("Chip erase not supported\n");
387 
388 	printk("Device size: 0x%X bytes (%d MiB)\n", 1 << cfip->DevSize, 1<< (cfip->DevSize - 20));
389 	printk("Flash Device Interface description: 0x%4.4X\n", cfip->InterfaceDesc);
390 	switch(cfip->InterfaceDesc) {
391 	case CFI_INTERFACE_X8_ASYNC:
392 		printk("  - x8-only asynchronous interface\n");
393 		break;
394 
395 	case CFI_INTERFACE_X16_ASYNC:
396 		printk("  - x16-only asynchronous interface\n");
397 		break;
398 
399 	case CFI_INTERFACE_X8_BY_X16_ASYNC:
400 		printk("  - supports x8 and x16 via BYTE# with asynchronous interface\n");
401 		break;
402 
403 	case CFI_INTERFACE_X32_ASYNC:
404 		printk("  - x32-only asynchronous interface\n");
405 		break;
406 
407 	case CFI_INTERFACE_X16_BY_X32_ASYNC:
408 		printk("  - supports x16 and x32 via Word# with asynchronous interface\n");
409 		break;
410 
411 	case CFI_INTERFACE_NOT_ALLOWED:
412 		printk("  - Not Allowed / Reserved\n");
413 		break;
414 
415 	default:
416 		printk("  - Unknown\n");
417 		break;
418 	}
419 
420 	printk("Max. bytes in buffer write: 0x%x\n", 1<< cfip->MaxBufWriteSize);
421 	printk("Number of Erase Block Regions: %d\n", cfip->NumEraseRegions);
422 
423 }
424 #endif /* DEBUG_CFI */
425 
426 static struct chip_probe cfi_chip_probe = {
427 	.name		= "CFI",
428 	.probe_chip	= cfi_probe_chip
429 };
430 
431 struct mtd_info *cfi_probe(struct map_info *map)
432 {
433 	/*
434 	 * Just use the generic probe stuff to call our CFI-specific
435 	 * chip_probe routine in all the possible permutations, etc.
436 	 */
437 	return mtd_do_chip_probe(map, &cfi_chip_probe);
438 }
439 
440 static struct mtd_chip_driver cfi_chipdrv = {
441 	.probe		= cfi_probe,
442 	.name		= "cfi_probe",
443 	.module		= THIS_MODULE
444 };
445 
446 static int __init cfi_probe_init(void)
447 {
448 	register_mtd_chip_driver(&cfi_chipdrv);
449 	return 0;
450 }
451 
452 static void __exit cfi_probe_exit(void)
453 {
454 	unregister_mtd_chip_driver(&cfi_chipdrv);
455 }
456 
457 module_init(cfi_probe_init);
458 module_exit(cfi_probe_exit);
459 
460 MODULE_LICENSE("GPL");
461 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org> et al.");
462 MODULE_DESCRIPTION("Probe code for CFI-compliant flash chips");
463