xref: /openbmc/linux/drivers/mtd/chips/cfi_probe.c (revision 86e281fc)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3    Common Flash Interface probe code.
4    (C) 2000 Red Hat.
5 */
6 
7 #include <linux/module.h>
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <asm/io.h>
12 #include <asm/byteorder.h>
13 #include <linux/errno.h>
14 #include <linux/slab.h>
15 #include <linux/interrupt.h>
16 
17 #include <linux/mtd/xip.h>
18 #include <linux/mtd/map.h>
19 #include <linux/mtd/cfi.h>
20 #include <linux/mtd/gen_probe.h>
21 
22 //#define DEBUG_CFI
23 
24 #ifdef DEBUG_CFI
25 static void print_cfi_ident(struct cfi_ident *);
26 #endif
27 
28 static int cfi_probe_chip(struct map_info *map, __u32 base,
29 			  unsigned long *chip_map, struct cfi_private *cfi);
30 static int cfi_chip_setup(struct map_info *map, struct cfi_private *cfi);
31 
32 struct mtd_info *cfi_probe(struct map_info *map);
33 
34 #ifdef CONFIG_MTD_XIP
35 
36 /* only needed for short periods, so this is rather simple */
37 #define xip_disable()	local_irq_disable()
38 
39 #define xip_allowed(base, map) \
40 do { \
41 	(void) map_read(map, base); \
42 	xip_iprefetch(); \
43 	local_irq_enable(); \
44 } while (0)
45 
46 #define xip_enable(base, map, cfi) \
47 do { \
48 	cfi_qry_mode_off(base, map, cfi);		\
49 	xip_allowed(base, map); \
50 } while (0)
51 
52 #define xip_disable_qry(base, map, cfi) \
53 do { \
54 	xip_disable(); \
55 	cfi_qry_mode_on(base, map, cfi); \
56 } while (0)
57 
58 #else
59 
60 #define xip_disable()			do { } while (0)
61 #define xip_allowed(base, map)		do { } while (0)
62 #define xip_enable(base, map, cfi)	do { } while (0)
63 #define xip_disable_qry(base, map, cfi) do { } while (0)
64 
65 #endif
66 
67 /*
68  * This fixup occurs immediately after reading the CFI structure and can affect
69  * the number of chips detected, unlike cfi_fixup, which occurs after an
70  * mtd_info structure has been created for the chip.
71  */
72 struct cfi_early_fixup {
73 	uint16_t mfr;
74 	uint16_t id;
75 	void (*fixup)(struct cfi_private *cfi);
76 };
77 
78 static void cfi_early_fixup(struct cfi_private *cfi,
79 			    const struct cfi_early_fixup *fixups)
80 {
81 	const struct cfi_early_fixup *f;
82 
83 	for (f = fixups; f->fixup; f++) {
84 		if (((f->mfr == CFI_MFR_ANY) || (f->mfr == cfi->mfr)) &&
85 		    ((f->id == CFI_ID_ANY) || (f->id == cfi->id))) {
86 			f->fixup(cfi);
87 		}
88 	}
89 }
90 
91 /* check for QRY.
92    in: interleave,type,mode
93    ret: table index, <0 for error
94  */
95 
96 static int __xipram cfi_probe_chip(struct map_info *map, __u32 base,
97 				   unsigned long *chip_map, struct cfi_private *cfi)
98 {
99 	int i;
100 
101 	if ((base + 0) >= map->size) {
102 		printk(KERN_NOTICE
103 			"Probe at base[0x00](0x%08lx) past the end of the map(0x%08lx)\n",
104 			(unsigned long)base, map->size -1);
105 		return 0;
106 	}
107 	if ((base + 0xff) >= map->size) {
108 		printk(KERN_NOTICE
109 			"Probe at base[0x55](0x%08lx) past the end of the map(0x%08lx)\n",
110 			(unsigned long)base + 0x55, map->size -1);
111 		return 0;
112 	}
113 
114 	xip_disable();
115 	if (!cfi_qry_mode_on(base, map, cfi)) {
116 		xip_enable(base, map, cfi);
117 		return 0;
118 	}
119 
120 	if (!cfi->numchips) {
121 		/* This is the first time we're called. Set up the CFI
122 		   stuff accordingly and return */
123 		return cfi_chip_setup(map, cfi);
124 	}
125 
126 	/* Check each previous chip to see if it's an alias */
127  	for (i=0; i < (base >> cfi->chipshift); i++) {
128  		unsigned long start;
129  		if(!test_bit(i, chip_map)) {
130 			/* Skip location; no valid chip at this address */
131  			continue;
132  		}
133  		start = i << cfi->chipshift;
134 		/* This chip should be in read mode if it's one
135 		   we've already touched. */
136 		if (cfi_qry_present(map, start, cfi)) {
137 			/* Eep. This chip also had the QRY marker.
138 			 * Is it an alias for the new one? */
139 			cfi_qry_mode_off(start, map, cfi);
140 
141 			/* If the QRY marker goes away, it's an alias */
142 			if (!cfi_qry_present(map, start, cfi)) {
143 				xip_allowed(base, map);
144 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
145 				       map->name, base, start);
146 				return 0;
147 			}
148 			/* Yes, it's actually got QRY for data. Most
149 			 * unfortunate. Stick the new chip in read mode
150 			 * too and if it's the same, assume it's an alias. */
151 			/* FIXME: Use other modes to do a proper check */
152 			cfi_qry_mode_off(base, map, cfi);
153 
154 			if (cfi_qry_present(map, base, cfi)) {
155 				xip_allowed(base, map);
156 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
157 				       map->name, base, start);
158 				return 0;
159 			}
160 		}
161 	}
162 
163 	/* OK, if we got to here, then none of the previous chips appear to
164 	   be aliases for the current one. */
165 	set_bit((base >> cfi->chipshift), chip_map); /* Update chip map */
166 	cfi->numchips++;
167 
168 	/* Put it back into Read Mode */
169 	cfi_qry_mode_off(base, map, cfi);
170 	xip_allowed(base, map);
171 
172 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
173 	       map->name, cfi->interleave, cfi->device_type*8, base,
174 	       map->bankwidth*8);
175 
176 	return 1;
177 }
178 
179 static void fixup_s70gl02gs_chips(struct cfi_private *cfi)
180 {
181 	/*
182 	 * S70GL02GS flash reports a single 256 MiB chip, but is really made up
183 	 * of two 128 MiB chips with 1024 sectors each.
184 	 */
185 	cfi->cfiq->DevSize = 27;
186 	cfi->cfiq->EraseRegionInfo[0] = 0x20003ff;
187 	pr_warn("Bad S70GL02GS CFI data; adjust to detect 2 chips\n");
188 }
189 
190 static const struct cfi_early_fixup cfi_early_fixup_table[] = {
191 	{ CFI_MFR_AMD, 0x4801, fixup_s70gl02gs_chips },
192 	{ },
193 };
194 
195 static int __xipram cfi_chip_setup(struct map_info *map,
196 				   struct cfi_private *cfi)
197 {
198 	int ofs_factor = cfi->interleave*cfi->device_type;
199 	__u32 base = 0;
200 	int num_erase_regions = cfi_read_query(map, base + (0x10 + 28)*ofs_factor);
201 	int i;
202 	int addr_unlock1 = 0x555, addr_unlock2 = 0x2AA;
203 
204 	xip_enable(base, map, cfi);
205 #ifdef DEBUG_CFI
206 	printk("Number of erase regions: %d\n", num_erase_regions);
207 #endif
208 	if (!num_erase_regions)
209 		return 0;
210 
211 	cfi->cfiq = kmalloc(sizeof(struct cfi_ident) + num_erase_regions * 4, GFP_KERNEL);
212 	if (!cfi->cfiq)
213 		return 0;
214 
215 	memset(cfi->cfiq,0,sizeof(struct cfi_ident));
216 
217 	cfi->cfi_mode = CFI_MODE_CFI;
218 
219 	cfi->sector_erase_cmd = CMD(0x30);
220 
221 	/* Read the CFI info structure */
222 	xip_disable_qry(base, map, cfi);
223 	for (i=0; i<(sizeof(struct cfi_ident) + num_erase_regions * 4); i++)
224 		((unsigned char *)cfi->cfiq)[i] = cfi_read_query(map,base + (0x10 + i)*ofs_factor);
225 
226 	/* Do any necessary byteswapping */
227 	cfi->cfiq->P_ID = le16_to_cpu(cfi->cfiq->P_ID);
228 
229 	cfi->cfiq->P_ADR = le16_to_cpu(cfi->cfiq->P_ADR);
230 	cfi->cfiq->A_ID = le16_to_cpu(cfi->cfiq->A_ID);
231 	cfi->cfiq->A_ADR = le16_to_cpu(cfi->cfiq->A_ADR);
232 	cfi->cfiq->InterfaceDesc = le16_to_cpu(cfi->cfiq->InterfaceDesc);
233 	cfi->cfiq->MaxBufWriteSize = le16_to_cpu(cfi->cfiq->MaxBufWriteSize);
234 
235 #ifdef DEBUG_CFI
236 	/* Dump the information therein */
237 	print_cfi_ident(cfi->cfiq);
238 #endif
239 
240 	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
241 		cfi->cfiq->EraseRegionInfo[i] = le32_to_cpu(cfi->cfiq->EraseRegionInfo[i]);
242 
243 #ifdef DEBUG_CFI
244 		printk("  Erase Region #%d: BlockSize 0x%4.4X bytes, %d blocks\n",
245 		       i, (cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff,
246 		       (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1);
247 #endif
248 	}
249 
250 	if (cfi->cfiq->P_ID == P_ID_SST_OLD) {
251 		addr_unlock1 = 0x5555;
252 		addr_unlock2 = 0x2AAA;
253 	}
254 
255 	/*
256 	 * Note we put the device back into Read Mode BEFORE going into Auto
257 	 * Select Mode, as some devices support nesting of modes, others
258 	 * don't. This way should always work.
259 	 * On cmdset 0001 the writes of 0xaa and 0x55 are not needed, and
260 	 * so should be treated as nops or illegal (and so put the device
261 	 * back into Read Mode, which is a nop in this case).
262 	 */
263 	cfi_send_gen_cmd(0xf0,     0, base, map, cfi, cfi->device_type, NULL);
264 	cfi_send_gen_cmd(0xaa, addr_unlock1, base, map, cfi, cfi->device_type, NULL);
265 	cfi_send_gen_cmd(0x55, addr_unlock2, base, map, cfi, cfi->device_type, NULL);
266 	cfi_send_gen_cmd(0x90, addr_unlock1, base, map, cfi, cfi->device_type, NULL);
267 	cfi->mfr = cfi_read_query16(map, base);
268 	cfi->id = cfi_read_query16(map, base + ofs_factor);
269 
270 	/* Get AMD/Spansion extended JEDEC ID */
271 	if (cfi->mfr == CFI_MFR_AMD && (cfi->id & 0xff) == 0x7e)
272 		cfi->id = cfi_read_query(map, base + 0xe * ofs_factor) << 8 |
273 			  cfi_read_query(map, base + 0xf * ofs_factor);
274 
275 	/* Put it back into Read Mode */
276 	cfi_qry_mode_off(base, map, cfi);
277 	xip_allowed(base, map);
278 
279 	cfi_early_fixup(cfi, cfi_early_fixup_table);
280 
281 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank. Manufacturer ID %#08x Chip ID %#08x\n",
282 	       map->name, cfi->interleave, cfi->device_type*8, base,
283 	       map->bankwidth*8, cfi->mfr, cfi->id);
284 
285 	return 1;
286 }
287 
288 #ifdef DEBUG_CFI
289 static char *vendorname(__u16 vendor)
290 {
291 	switch (vendor) {
292 	case P_ID_NONE:
293 		return "None";
294 
295 	case P_ID_INTEL_EXT:
296 		return "Intel/Sharp Extended";
297 
298 	case P_ID_AMD_STD:
299 		return "AMD/Fujitsu Standard";
300 
301 	case P_ID_INTEL_STD:
302 		return "Intel/Sharp Standard";
303 
304 	case P_ID_AMD_EXT:
305 		return "AMD/Fujitsu Extended";
306 
307 	case P_ID_WINBOND:
308 		return "Winbond Standard";
309 
310 	case P_ID_ST_ADV:
311 		return "ST Advanced";
312 
313 	case P_ID_MITSUBISHI_STD:
314 		return "Mitsubishi Standard";
315 
316 	case P_ID_MITSUBISHI_EXT:
317 		return "Mitsubishi Extended";
318 
319 	case P_ID_SST_PAGE:
320 		return "SST Page Write";
321 
322 	case P_ID_SST_OLD:
323 		return "SST 39VF160x/39VF320x";
324 
325 	case P_ID_INTEL_PERFORMANCE:
326 		return "Intel Performance Code";
327 
328 	case P_ID_INTEL_DATA:
329 		return "Intel Data";
330 
331 	case P_ID_RESERVED:
332 		return "Not Allowed / Reserved for Future Use";
333 
334 	default:
335 		return "Unknown";
336 	}
337 }
338 
339 
340 static void print_cfi_ident(struct cfi_ident *cfip)
341 {
342 #if 0
343 	if (cfip->qry[0] != 'Q' || cfip->qry[1] != 'R' || cfip->qry[2] != 'Y') {
344 		printk("Invalid CFI ident structure.\n");
345 		return;
346 	}
347 #endif
348 	printk("Primary Vendor Command Set: %4.4X (%s)\n", cfip->P_ID, vendorname(cfip->P_ID));
349 	if (cfip->P_ADR)
350 		printk("Primary Algorithm Table at %4.4X\n", cfip->P_ADR);
351 	else
352 		printk("No Primary Algorithm Table\n");
353 
354 	printk("Alternative Vendor Command Set: %4.4X (%s)\n", cfip->A_ID, vendorname(cfip->A_ID));
355 	if (cfip->A_ADR)
356 		printk("Alternate Algorithm Table at %4.4X\n", cfip->A_ADR);
357 	else
358 		printk("No Alternate Algorithm Table\n");
359 
360 
361 	printk("Vcc Minimum: %2d.%d V\n", cfip->VccMin >> 4, cfip->VccMin & 0xf);
362 	printk("Vcc Maximum: %2d.%d V\n", cfip->VccMax >> 4, cfip->VccMax & 0xf);
363 	if (cfip->VppMin) {
364 		printk("Vpp Minimum: %2d.%d V\n", cfip->VppMin >> 4, cfip->VppMin & 0xf);
365 		printk("Vpp Maximum: %2d.%d V\n", cfip->VppMax >> 4, cfip->VppMax & 0xf);
366 	}
367 	else
368 		printk("No Vpp line\n");
369 
370 	printk("Typical byte/word write timeout: %d µs\n", 1<<cfip->WordWriteTimeoutTyp);
371 	printk("Maximum byte/word write timeout: %d µs\n", (1<<cfip->WordWriteTimeoutMax) * (1<<cfip->WordWriteTimeoutTyp));
372 
373 	if (cfip->BufWriteTimeoutTyp || cfip->BufWriteTimeoutMax) {
374 		printk("Typical full buffer write timeout: %d µs\n", 1<<cfip->BufWriteTimeoutTyp);
375 		printk("Maximum full buffer write timeout: %d µs\n", (1<<cfip->BufWriteTimeoutMax) * (1<<cfip->BufWriteTimeoutTyp));
376 	}
377 	else
378 		printk("Full buffer write not supported\n");
379 
380 	printk("Typical block erase timeout: %d ms\n", 1<<cfip->BlockEraseTimeoutTyp);
381 	printk("Maximum block erase timeout: %d ms\n", (1<<cfip->BlockEraseTimeoutMax) * (1<<cfip->BlockEraseTimeoutTyp));
382 	if (cfip->ChipEraseTimeoutTyp || cfip->ChipEraseTimeoutMax) {
383 		printk("Typical chip erase timeout: %d ms\n", 1<<cfip->ChipEraseTimeoutTyp);
384 		printk("Maximum chip erase timeout: %d ms\n", (1<<cfip->ChipEraseTimeoutMax) * (1<<cfip->ChipEraseTimeoutTyp));
385 	}
386 	else
387 		printk("Chip erase not supported\n");
388 
389 	printk("Device size: 0x%X bytes (%d MiB)\n", 1 << cfip->DevSize, 1<< (cfip->DevSize - 20));
390 	printk("Flash Device Interface description: 0x%4.4X\n", cfip->InterfaceDesc);
391 	switch(cfip->InterfaceDesc) {
392 	case CFI_INTERFACE_X8_ASYNC:
393 		printk("  - x8-only asynchronous interface\n");
394 		break;
395 
396 	case CFI_INTERFACE_X16_ASYNC:
397 		printk("  - x16-only asynchronous interface\n");
398 		break;
399 
400 	case CFI_INTERFACE_X8_BY_X16_ASYNC:
401 		printk("  - supports x8 and x16 via BYTE# with asynchronous interface\n");
402 		break;
403 
404 	case CFI_INTERFACE_X32_ASYNC:
405 		printk("  - x32-only asynchronous interface\n");
406 		break;
407 
408 	case CFI_INTERFACE_X16_BY_X32_ASYNC:
409 		printk("  - supports x16 and x32 via Word# with asynchronous interface\n");
410 		break;
411 
412 	case CFI_INTERFACE_NOT_ALLOWED:
413 		printk("  - Not Allowed / Reserved\n");
414 		break;
415 
416 	default:
417 		printk("  - Unknown\n");
418 		break;
419 	}
420 
421 	printk("Max. bytes in buffer write: 0x%x\n", 1<< cfip->MaxBufWriteSize);
422 	printk("Number of Erase Block Regions: %d\n", cfip->NumEraseRegions);
423 
424 }
425 #endif /* DEBUG_CFI */
426 
427 static struct chip_probe cfi_chip_probe = {
428 	.name		= "CFI",
429 	.probe_chip	= cfi_probe_chip
430 };
431 
432 struct mtd_info *cfi_probe(struct map_info *map)
433 {
434 	/*
435 	 * Just use the generic probe stuff to call our CFI-specific
436 	 * chip_probe routine in all the possible permutations, etc.
437 	 */
438 	return mtd_do_chip_probe(map, &cfi_chip_probe);
439 }
440 
441 static struct mtd_chip_driver cfi_chipdrv = {
442 	.probe		= cfi_probe,
443 	.name		= "cfi_probe",
444 	.module		= THIS_MODULE
445 };
446 
447 static int __init cfi_probe_init(void)
448 {
449 	register_mtd_chip_driver(&cfi_chipdrv);
450 	return 0;
451 }
452 
453 static void __exit cfi_probe_exit(void)
454 {
455 	unregister_mtd_chip_driver(&cfi_chipdrv);
456 }
457 
458 module_init(cfi_probe_init);
459 module_exit(cfi_probe_exit);
460 
461 MODULE_LICENSE("GPL");
462 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org> et al.");
463 MODULE_DESCRIPTION("Probe code for CFI-compliant flash chips");
464