xref: /openbmc/linux/drivers/mtd/chips/cfi_probe.c (revision 1da177e4)
1 /*
2    Common Flash Interface probe code.
3    (C) 2000 Red Hat. GPL'd.
4    $Id: cfi_probe.c,v 1.83 2004/11/16 18:19:02 nico Exp $
5 */
6 
7 #include <linux/config.h>
8 #include <linux/module.h>
9 #include <linux/types.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <asm/io.h>
13 #include <asm/byteorder.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/interrupt.h>
17 
18 #include <linux/mtd/xip.h>
19 #include <linux/mtd/map.h>
20 #include <linux/mtd/cfi.h>
21 #include <linux/mtd/gen_probe.h>
22 
23 //#define DEBUG_CFI
24 
25 #ifdef DEBUG_CFI
26 static void print_cfi_ident(struct cfi_ident *);
27 #endif
28 
29 static int cfi_probe_chip(struct map_info *map, __u32 base,
30 			  unsigned long *chip_map, struct cfi_private *cfi);
31 static int cfi_chip_setup(struct map_info *map, struct cfi_private *cfi);
32 
33 struct mtd_info *cfi_probe(struct map_info *map);
34 
35 #ifdef CONFIG_MTD_XIP
36 
37 /* only needed for short periods, so this is rather simple */
38 #define xip_disable()	local_irq_disable()
39 
40 #define xip_allowed(base, map) \
41 do { \
42 	(void) map_read(map, base); \
43 	asm volatile (".rep 8; nop; .endr"); \
44 	local_irq_enable(); \
45 } while (0)
46 
47 #define xip_enable(base, map, cfi) \
48 do { \
49 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL); \
50 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL); \
51 	xip_allowed(base, map); \
52 } while (0)
53 
54 #define xip_disable_qry(base, map, cfi) \
55 do { \
56 	xip_disable(); \
57 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL); \
58 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL); \
59 	cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL); \
60 } while (0)
61 
62 #else
63 
64 #define xip_disable()			do { } while (0)
65 #define xip_allowed(base, map)		do { } while (0)
66 #define xip_enable(base, map, cfi)	do { } while (0)
67 #define xip_disable_qry(base, map, cfi) do { } while (0)
68 
69 #endif
70 
71 /* check for QRY.
72    in: interleave,type,mode
73    ret: table index, <0 for error
74  */
75 static int __xipram qry_present(struct map_info *map, __u32 base,
76 				struct cfi_private *cfi)
77 {
78 	int osf = cfi->interleave * cfi->device_type;	// scale factor
79 	map_word val[3];
80 	map_word qry[3];
81 
82 	qry[0] = cfi_build_cmd('Q', map, cfi);
83 	qry[1] = cfi_build_cmd('R', map, cfi);
84 	qry[2] = cfi_build_cmd('Y', map, cfi);
85 
86 	val[0] = map_read(map, base + osf*0x10);
87 	val[1] = map_read(map, base + osf*0x11);
88 	val[2] = map_read(map, base + osf*0x12);
89 
90 	if (!map_word_equal(map, qry[0], val[0]))
91 		return 0;
92 
93 	if (!map_word_equal(map, qry[1], val[1]))
94 		return 0;
95 
96 	if (!map_word_equal(map, qry[2], val[2]))
97 		return 0;
98 
99 	return 1; 	// "QRY" found
100 }
101 
102 static int __xipram cfi_probe_chip(struct map_info *map, __u32 base,
103 				   unsigned long *chip_map, struct cfi_private *cfi)
104 {
105 	int i;
106 
107 	if ((base + 0) >= map->size) {
108 		printk(KERN_NOTICE
109 			"Probe at base[0x00](0x%08lx) past the end of the map(0x%08lx)\n",
110 			(unsigned long)base, map->size -1);
111 		return 0;
112 	}
113 	if ((base + 0xff) >= map->size) {
114 		printk(KERN_NOTICE
115 			"Probe at base[0x55](0x%08lx) past the end of the map(0x%08lx)\n",
116 			(unsigned long)base + 0x55, map->size -1);
117 		return 0;
118 	}
119 
120 	xip_disable();
121 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
122 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
123 	cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);
124 
125 	if (!qry_present(map,base,cfi)) {
126 		xip_enable(base, map, cfi);
127 		return 0;
128 	}
129 
130 	if (!cfi->numchips) {
131 		/* This is the first time we're called. Set up the CFI
132 		   stuff accordingly and return */
133 		return cfi_chip_setup(map, cfi);
134 	}
135 
136 	/* Check each previous chip to see if it's an alias */
137  	for (i=0; i < (base >> cfi->chipshift); i++) {
138  		unsigned long start;
139  		if(!test_bit(i, chip_map)) {
140 			/* Skip location; no valid chip at this address */
141  			continue;
142  		}
143  		start = i << cfi->chipshift;
144 		/* This chip should be in read mode if it's one
145 		   we've already touched. */
146 		if (qry_present(map, start, cfi)) {
147 			/* Eep. This chip also had the QRY marker.
148 			 * Is it an alias for the new one? */
149 			cfi_send_gen_cmd(0xF0, 0, start, map, cfi, cfi->device_type, NULL);
150 			cfi_send_gen_cmd(0xFF, 0, start, map, cfi, cfi->device_type, NULL);
151 
152 			/* If the QRY marker goes away, it's an alias */
153 			if (!qry_present(map, start, 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 			/* Yes, it's actually got QRY for data. Most
160 			 * unfortunate. Stick the new chip in read mode
161 			 * too and if it's the same, assume it's an alias. */
162 			/* FIXME: Use other modes to do a proper check */
163 			cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
164 			cfi_send_gen_cmd(0xFF, 0, start, map, cfi, cfi->device_type, NULL);
165 
166 			if (qry_present(map, base, cfi)) {
167 				xip_allowed(base, map);
168 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
169 				       map->name, base, start);
170 				return 0;
171 			}
172 		}
173 	}
174 
175 	/* OK, if we got to here, then none of the previous chips appear to
176 	   be aliases for the current one. */
177 	set_bit((base >> cfi->chipshift), chip_map); /* Update chip map */
178 	cfi->numchips++;
179 
180 	/* Put it back into Read Mode */
181 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
182 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
183 	xip_allowed(base, map);
184 
185 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
186 	       map->name, cfi->interleave, cfi->device_type*8, base,
187 	       map->bankwidth*8);
188 
189 	return 1;
190 }
191 
192 static int __xipram cfi_chip_setup(struct map_info *map,
193 				   struct cfi_private *cfi)
194 {
195 	int ofs_factor = cfi->interleave*cfi->device_type;
196 	__u32 base = 0;
197 	int num_erase_regions = cfi_read_query(map, base + (0x10 + 28)*ofs_factor);
198 	int i;
199 
200 	xip_enable(base, map, cfi);
201 #ifdef DEBUG_CFI
202 	printk("Number of erase regions: %d\n", num_erase_regions);
203 #endif
204 	if (!num_erase_regions)
205 		return 0;
206 
207 	cfi->cfiq = kmalloc(sizeof(struct cfi_ident) + num_erase_regions * 4, GFP_KERNEL);
208 	if (!cfi->cfiq) {
209 		printk(KERN_WARNING "%s: kmalloc failed for CFI ident structure\n", map->name);
210 		return 0;
211 	}
212 
213 	memset(cfi->cfiq,0,sizeof(struct cfi_ident));
214 
215 	cfi->cfi_mode = CFI_MODE_CFI;
216 
217 	/* Read the CFI info structure */
218 	xip_disable_qry(base, map, cfi);
219 	for (i=0; i<(sizeof(struct cfi_ident) + num_erase_regions * 4); i++)
220 		((unsigned char *)cfi->cfiq)[i] = cfi_read_query(map,base + (0x10 + i)*ofs_factor);
221 
222 	/* Note we put the device back into Read Mode BEFORE going into Auto
223 	 * Select Mode, as some devices support nesting of modes, others
224 	 * don't. This way should always work.
225 	 * On cmdset 0001 the writes of 0xaa and 0x55 are not needed, and
226 	 * so should be treated as nops or illegal (and so put the device
227 	 * back into Read Mode, which is a nop in this case).
228 	 */
229 	cfi_send_gen_cmd(0xf0,     0, base, map, cfi, cfi->device_type, NULL);
230 	cfi_send_gen_cmd(0xaa, 0x555, base, map, cfi, cfi->device_type, NULL);
231 	cfi_send_gen_cmd(0x55, 0x2aa, base, map, cfi, cfi->device_type, NULL);
232 	cfi_send_gen_cmd(0x90, 0x555, base, map, cfi, cfi->device_type, NULL);
233 	cfi->mfr = cfi_read_query(map, base);
234 	cfi->id = cfi_read_query(map, base + ofs_factor);
235 
236 	/* Put it back into Read Mode */
237 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
238 	/* ... even if it's an Intel chip */
239 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
240 	xip_allowed(base, map);
241 
242 	/* Do any necessary byteswapping */
243 	cfi->cfiq->P_ID = le16_to_cpu(cfi->cfiq->P_ID);
244 
245 	cfi->cfiq->P_ADR = le16_to_cpu(cfi->cfiq->P_ADR);
246 	cfi->cfiq->A_ID = le16_to_cpu(cfi->cfiq->A_ID);
247 	cfi->cfiq->A_ADR = le16_to_cpu(cfi->cfiq->A_ADR);
248 	cfi->cfiq->InterfaceDesc = le16_to_cpu(cfi->cfiq->InterfaceDesc);
249 	cfi->cfiq->MaxBufWriteSize = le16_to_cpu(cfi->cfiq->MaxBufWriteSize);
250 
251 #ifdef DEBUG_CFI
252 	/* Dump the information therein */
253 	print_cfi_ident(cfi->cfiq);
254 #endif
255 
256 	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
257 		cfi->cfiq->EraseRegionInfo[i] = le32_to_cpu(cfi->cfiq->EraseRegionInfo[i]);
258 
259 #ifdef DEBUG_CFI
260 		printk("  Erase Region #%d: BlockSize 0x%4.4X bytes, %d blocks\n",
261 		       i, (cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff,
262 		       (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1);
263 #endif
264 	}
265 
266 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
267 	       map->name, cfi->interleave, cfi->device_type*8, base,
268 	       map->bankwidth*8);
269 
270 	return 1;
271 }
272 
273 #ifdef DEBUG_CFI
274 static char *vendorname(__u16 vendor)
275 {
276 	switch (vendor) {
277 	case P_ID_NONE:
278 		return "None";
279 
280 	case P_ID_INTEL_EXT:
281 		return "Intel/Sharp Extended";
282 
283 	case P_ID_AMD_STD:
284 		return "AMD/Fujitsu Standard";
285 
286 	case P_ID_INTEL_STD:
287 		return "Intel/Sharp Standard";
288 
289 	case P_ID_AMD_EXT:
290 		return "AMD/Fujitsu Extended";
291 
292 	case P_ID_WINBOND:
293 		return "Winbond Standard";
294 
295 	case P_ID_ST_ADV:
296 		return "ST Advanced";
297 
298 	case P_ID_MITSUBISHI_STD:
299 		return "Mitsubishi Standard";
300 
301 	case P_ID_MITSUBISHI_EXT:
302 		return "Mitsubishi Extended";
303 
304 	case P_ID_SST_PAGE:
305 		return "SST Page Write";
306 
307 	case P_ID_INTEL_PERFORMANCE:
308 		return "Intel Performance Code";
309 
310 	case P_ID_INTEL_DATA:
311 		return "Intel Data";
312 
313 	case P_ID_RESERVED:
314 		return "Not Allowed / Reserved for Future Use";
315 
316 	default:
317 		return "Unknown";
318 	}
319 }
320 
321 
322 static void print_cfi_ident(struct cfi_ident *cfip)
323 {
324 #if 0
325 	if (cfip->qry[0] != 'Q' || cfip->qry[1] != 'R' || cfip->qry[2] != 'Y') {
326 		printk("Invalid CFI ident structure.\n");
327 		return;
328 	}
329 #endif
330 	printk("Primary Vendor Command Set: %4.4X (%s)\n", cfip->P_ID, vendorname(cfip->P_ID));
331 	if (cfip->P_ADR)
332 		printk("Primary Algorithm Table at %4.4X\n", cfip->P_ADR);
333 	else
334 		printk("No Primary Algorithm Table\n");
335 
336 	printk("Alternative Vendor Command Set: %4.4X (%s)\n", cfip->A_ID, vendorname(cfip->A_ID));
337 	if (cfip->A_ADR)
338 		printk("Alternate Algorithm Table at %4.4X\n", cfip->A_ADR);
339 	else
340 		printk("No Alternate Algorithm Table\n");
341 
342 
343 	printk("Vcc Minimum: %2d.%d V\n", cfip->VccMin >> 4, cfip->VccMin & 0xf);
344 	printk("Vcc Maximum: %2d.%d V\n", cfip->VccMax >> 4, cfip->VccMax & 0xf);
345 	if (cfip->VppMin) {
346 		printk("Vpp Minimum: %2d.%d V\n", cfip->VppMin >> 4, cfip->VppMin & 0xf);
347 		printk("Vpp Maximum: %2d.%d V\n", cfip->VppMax >> 4, cfip->VppMax & 0xf);
348 	}
349 	else
350 		printk("No Vpp line\n");
351 
352 	printk("Typical byte/word write timeout: %d �s\n", 1<<cfip->WordWriteTimeoutTyp);
353 	printk("Maximum byte/word write timeout: %d �s\n", (1<<cfip->WordWriteTimeoutMax) * (1<<cfip->WordWriteTimeoutTyp));
354 
355 	if (cfip->BufWriteTimeoutTyp || cfip->BufWriteTimeoutMax) {
356 		printk("Typical full buffer write timeout: %d �s\n", 1<<cfip->BufWriteTimeoutTyp);
357 		printk("Maximum full buffer write timeout: %d �s\n", (1<<cfip->BufWriteTimeoutMax) * (1<<cfip->BufWriteTimeoutTyp));
358 	}
359 	else
360 		printk("Full buffer write not supported\n");
361 
362 	printk("Typical block erase timeout: %d ms\n", 1<<cfip->BlockEraseTimeoutTyp);
363 	printk("Maximum block erase timeout: %d ms\n", (1<<cfip->BlockEraseTimeoutMax) * (1<<cfip->BlockEraseTimeoutTyp));
364 	if (cfip->ChipEraseTimeoutTyp || cfip->ChipEraseTimeoutMax) {
365 		printk("Typical chip erase timeout: %d ms\n", 1<<cfip->ChipEraseTimeoutTyp);
366 		printk("Maximum chip erase timeout: %d ms\n", (1<<cfip->ChipEraseTimeoutMax) * (1<<cfip->ChipEraseTimeoutTyp));
367 	}
368 	else
369 		printk("Chip erase not supported\n");
370 
371 	printk("Device size: 0x%X bytes (%d MiB)\n", 1 << cfip->DevSize, 1<< (cfip->DevSize - 20));
372 	printk("Flash Device Interface description: 0x%4.4X\n", cfip->InterfaceDesc);
373 	switch(cfip->InterfaceDesc) {
374 	case 0:
375 		printk("  - x8-only asynchronous interface\n");
376 		break;
377 
378 	case 1:
379 		printk("  - x16-only asynchronous interface\n");
380 		break;
381 
382 	case 2:
383 		printk("  - supports x8 and x16 via BYTE# with asynchronous interface\n");
384 		break;
385 
386 	case 3:
387 		printk("  - x32-only asynchronous interface\n");
388 		break;
389 
390 	case 4:
391 		printk("  - supports x16 and x32 via Word# with asynchronous interface\n");
392 		break;
393 
394 	case 65535:
395 		printk("  - Not Allowed / Reserved\n");
396 		break;
397 
398 	default:
399 		printk("  - Unknown\n");
400 		break;
401 	}
402 
403 	printk("Max. bytes in buffer write: 0x%x\n", 1<< cfip->MaxBufWriteSize);
404 	printk("Number of Erase Block Regions: %d\n", cfip->NumEraseRegions);
405 
406 }
407 #endif /* DEBUG_CFI */
408 
409 static struct chip_probe cfi_chip_probe = {
410 	.name		= "CFI",
411 	.probe_chip	= cfi_probe_chip
412 };
413 
414 struct mtd_info *cfi_probe(struct map_info *map)
415 {
416 	/*
417 	 * Just use the generic probe stuff to call our CFI-specific
418 	 * chip_probe routine in all the possible permutations, etc.
419 	 */
420 	return mtd_do_chip_probe(map, &cfi_chip_probe);
421 }
422 
423 static struct mtd_chip_driver cfi_chipdrv = {
424 	.probe		= cfi_probe,
425 	.name		= "cfi_probe",
426 	.module		= THIS_MODULE
427 };
428 
429 int __init cfi_probe_init(void)
430 {
431 	register_mtd_chip_driver(&cfi_chipdrv);
432 	return 0;
433 }
434 
435 static void __exit cfi_probe_exit(void)
436 {
437 	unregister_mtd_chip_driver(&cfi_chipdrv);
438 }
439 
440 module_init(cfi_probe_init);
441 module_exit(cfi_probe_exit);
442 
443 MODULE_LICENSE("GPL");
444 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org> et al.");
445 MODULE_DESCRIPTION("Probe code for CFI-compliant flash chips");
446