xref: /openbmc/linux/drivers/mtd/chips/cfi_probe.c (revision 643d1f7f)
1 /*
2    Common Flash Interface probe code.
3    (C) 2000 Red Hat. GPL'd.
4    $Id: cfi_probe.c,v 1.86 2005/11/29 14:48:31 gleixner Exp $
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 	asm volatile (".rep 8; nop; .endr"); \
43 	local_irq_enable(); \
44 } while (0)
45 
46 #define xip_enable(base, map, cfi) \
47 do { \
48 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL); \
49 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL); \
50 	xip_allowed(base, map); \
51 } while (0)
52 
53 #define xip_disable_qry(base, map, cfi) \
54 do { \
55 	xip_disable(); \
56 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL); \
57 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL); \
58 	cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL); \
59 } while (0)
60 
61 #else
62 
63 #define xip_disable()			do { } while (0)
64 #define xip_allowed(base, map)		do { } while (0)
65 #define xip_enable(base, map, cfi)	do { } while (0)
66 #define xip_disable_qry(base, map, cfi) do { } while (0)
67 
68 #endif
69 
70 /* check for QRY.
71    in: interleave,type,mode
72    ret: table index, <0 for error
73  */
74 static int __xipram qry_present(struct map_info *map, __u32 base,
75 				struct cfi_private *cfi)
76 {
77 	int osf = cfi->interleave * cfi->device_type;	// scale factor
78 	map_word val[3];
79 	map_word qry[3];
80 
81 	qry[0] = cfi_build_cmd('Q', map, cfi);
82 	qry[1] = cfi_build_cmd('R', map, cfi);
83 	qry[2] = cfi_build_cmd('Y', map, cfi);
84 
85 	val[0] = map_read(map, base + osf*0x10);
86 	val[1] = map_read(map, base + osf*0x11);
87 	val[2] = map_read(map, base + osf*0x12);
88 
89 	if (!map_word_equal(map, qry[0], val[0]))
90 		return 0;
91 
92 	if (!map_word_equal(map, qry[1], val[1]))
93 		return 0;
94 
95 	if (!map_word_equal(map, qry[2], val[2]))
96 		return 0;
97 
98 	return 1; 	// "QRY" found
99 }
100 
101 static int __xipram cfi_probe_chip(struct map_info *map, __u32 base,
102 				   unsigned long *chip_map, struct cfi_private *cfi)
103 {
104 	int i;
105 
106 	if ((base + 0) >= map->size) {
107 		printk(KERN_NOTICE
108 			"Probe at base[0x00](0x%08lx) past the end of the map(0x%08lx)\n",
109 			(unsigned long)base, map->size -1);
110 		return 0;
111 	}
112 	if ((base + 0xff) >= map->size) {
113 		printk(KERN_NOTICE
114 			"Probe at base[0x55](0x%08lx) past the end of the map(0x%08lx)\n",
115 			(unsigned long)base + 0x55, map->size -1);
116 		return 0;
117 	}
118 
119 	xip_disable();
120 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
121 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
122 	cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);
123 
124 	if (!qry_present(map,base,cfi)) {
125 		xip_enable(base, map, cfi);
126 		return 0;
127 	}
128 
129 	if (!cfi->numchips) {
130 		/* This is the first time we're called. Set up the CFI
131 		   stuff accordingly and return */
132 		return cfi_chip_setup(map, cfi);
133 	}
134 
135 	/* Check each previous chip to see if it's an alias */
136  	for (i=0; i < (base >> cfi->chipshift); i++) {
137  		unsigned long start;
138  		if(!test_bit(i, chip_map)) {
139 			/* Skip location; no valid chip at this address */
140  			continue;
141  		}
142  		start = i << cfi->chipshift;
143 		/* This chip should be in read mode if it's one
144 		   we've already touched. */
145 		if (qry_present(map, start, cfi)) {
146 			/* Eep. This chip also had the QRY marker.
147 			 * Is it an alias for the new one? */
148 			cfi_send_gen_cmd(0xF0, 0, start, map, cfi, cfi->device_type, NULL);
149 			cfi_send_gen_cmd(0xFF, 0, start, map, cfi, cfi->device_type, NULL);
150 
151 			/* If the QRY marker goes away, it's an alias */
152 			if (!qry_present(map, start, cfi)) {
153 				xip_allowed(base, map);
154 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
155 				       map->name, base, start);
156 				return 0;
157 			}
158 			/* Yes, it's actually got QRY for data. Most
159 			 * unfortunate. Stick the new chip in read mode
160 			 * too and if it's the same, assume it's an alias. */
161 			/* FIXME: Use other modes to do a proper check */
162 			cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
163 			cfi_send_gen_cmd(0xFF, 0, start, map, cfi, cfi->device_type, NULL);
164 
165 			if (qry_present(map, base, cfi)) {
166 				xip_allowed(base, map);
167 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
168 				       map->name, base, start);
169 				return 0;
170 			}
171 		}
172 	}
173 
174 	/* OK, if we got to here, then none of the previous chips appear to
175 	   be aliases for the current one. */
176 	set_bit((base >> cfi->chipshift), chip_map); /* Update chip map */
177 	cfi->numchips++;
178 
179 	/* Put it back into Read Mode */
180 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
181 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
182 	xip_allowed(base, map);
183 
184 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
185 	       map->name, cfi->interleave, cfi->device_type*8, base,
186 	       map->bankwidth*8);
187 
188 	return 1;
189 }
190 
191 static int __xipram cfi_chip_setup(struct map_info *map,
192 				   struct cfi_private *cfi)
193 {
194 	int ofs_factor = cfi->interleave*cfi->device_type;
195 	__u32 base = 0;
196 	int num_erase_regions = cfi_read_query(map, base + (0x10 + 28)*ofs_factor);
197 	int i;
198 
199 	xip_enable(base, map, cfi);
200 #ifdef DEBUG_CFI
201 	printk("Number of erase regions: %d\n", num_erase_regions);
202 #endif
203 	if (!num_erase_regions)
204 		return 0;
205 
206 	cfi->cfiq = kmalloc(sizeof(struct cfi_ident) + num_erase_regions * 4, GFP_KERNEL);
207 	if (!cfi->cfiq) {
208 		printk(KERN_WARNING "%s: kmalloc failed for CFI ident structure\n", map->name);
209 		return 0;
210 	}
211 
212 	memset(cfi->cfiq,0,sizeof(struct cfi_ident));
213 
214 	cfi->cfi_mode = CFI_MODE_CFI;
215 
216 	/* Read the CFI info structure */
217 	xip_disable_qry(base, map, cfi);
218 	for (i=0; i<(sizeof(struct cfi_ident) + num_erase_regions * 4); i++)
219 		((unsigned char *)cfi->cfiq)[i] = cfi_read_query(map,base + (0x10 + i)*ofs_factor);
220 
221 	/* Note we put the device back into Read Mode BEFORE going into Auto
222 	 * Select Mode, as some devices support nesting of modes, others
223 	 * don't. This way should always work.
224 	 * On cmdset 0001 the writes of 0xaa and 0x55 are not needed, and
225 	 * so should be treated as nops or illegal (and so put the device
226 	 * back into Read Mode, which is a nop in this case).
227 	 */
228 	cfi_send_gen_cmd(0xf0,     0, base, map, cfi, cfi->device_type, NULL);
229 	cfi_send_gen_cmd(0xaa, 0x555, base, map, cfi, cfi->device_type, NULL);
230 	cfi_send_gen_cmd(0x55, 0x2aa, base, map, cfi, cfi->device_type, NULL);
231 	cfi_send_gen_cmd(0x90, 0x555, base, map, cfi, cfi->device_type, NULL);
232 	cfi->mfr = cfi_read_query16(map, base);
233 	cfi->id = cfi_read_query16(map, base + ofs_factor);
234 
235 	/* Put it back into Read Mode */
236 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
237 	/* ... even if it's an Intel chip */
238 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
239 	xip_allowed(base, map);
240 
241 	/* Do any necessary byteswapping */
242 	cfi->cfiq->P_ID = le16_to_cpu(cfi->cfiq->P_ID);
243 
244 	cfi->cfiq->P_ADR = le16_to_cpu(cfi->cfiq->P_ADR);
245 	cfi->cfiq->A_ID = le16_to_cpu(cfi->cfiq->A_ID);
246 	cfi->cfiq->A_ADR = le16_to_cpu(cfi->cfiq->A_ADR);
247 	cfi->cfiq->InterfaceDesc = le16_to_cpu(cfi->cfiq->InterfaceDesc);
248 	cfi->cfiq->MaxBufWriteSize = le16_to_cpu(cfi->cfiq->MaxBufWriteSize);
249 
250 #ifdef DEBUG_CFI
251 	/* Dump the information therein */
252 	print_cfi_ident(cfi->cfiq);
253 #endif
254 
255 	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
256 		cfi->cfiq->EraseRegionInfo[i] = le32_to_cpu(cfi->cfiq->EraseRegionInfo[i]);
257 
258 #ifdef DEBUG_CFI
259 		printk("  Erase Region #%d: BlockSize 0x%4.4X bytes, %d blocks\n",
260 		       i, (cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff,
261 		       (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1);
262 #endif
263 	}
264 
265 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
266 	       map->name, cfi->interleave, cfi->device_type*8, base,
267 	       map->bankwidth*8);
268 
269 	return 1;
270 }
271 
272 #ifdef DEBUG_CFI
273 static char *vendorname(__u16 vendor)
274 {
275 	switch (vendor) {
276 	case P_ID_NONE:
277 		return "None";
278 
279 	case P_ID_INTEL_EXT:
280 		return "Intel/Sharp Extended";
281 
282 	case P_ID_AMD_STD:
283 		return "AMD/Fujitsu Standard";
284 
285 	case P_ID_INTEL_STD:
286 		return "Intel/Sharp Standard";
287 
288 	case P_ID_AMD_EXT:
289 		return "AMD/Fujitsu Extended";
290 
291 	case P_ID_WINBOND:
292 		return "Winbond Standard";
293 
294 	case P_ID_ST_ADV:
295 		return "ST Advanced";
296 
297 	case P_ID_MITSUBISHI_STD:
298 		return "Mitsubishi Standard";
299 
300 	case P_ID_MITSUBISHI_EXT:
301 		return "Mitsubishi Extended";
302 
303 	case P_ID_SST_PAGE:
304 		return "SST Page Write";
305 
306 	case P_ID_INTEL_PERFORMANCE:
307 		return "Intel Performance Code";
308 
309 	case P_ID_INTEL_DATA:
310 		return "Intel Data";
311 
312 	case P_ID_RESERVED:
313 		return "Not Allowed / Reserved for Future Use";
314 
315 	default:
316 		return "Unknown";
317 	}
318 }
319 
320 
321 static void print_cfi_ident(struct cfi_ident *cfip)
322 {
323 #if 0
324 	if (cfip->qry[0] != 'Q' || cfip->qry[1] != 'R' || cfip->qry[2] != 'Y') {
325 		printk("Invalid CFI ident structure.\n");
326 		return;
327 	}
328 #endif
329 	printk("Primary Vendor Command Set: %4.4X (%s)\n", cfip->P_ID, vendorname(cfip->P_ID));
330 	if (cfip->P_ADR)
331 		printk("Primary Algorithm Table at %4.4X\n", cfip->P_ADR);
332 	else
333 		printk("No Primary Algorithm Table\n");
334 
335 	printk("Alternative Vendor Command Set: %4.4X (%s)\n", cfip->A_ID, vendorname(cfip->A_ID));
336 	if (cfip->A_ADR)
337 		printk("Alternate Algorithm Table at %4.4X\n", cfip->A_ADR);
338 	else
339 		printk("No Alternate Algorithm Table\n");
340 
341 
342 	printk("Vcc Minimum: %2d.%d V\n", cfip->VccMin >> 4, cfip->VccMin & 0xf);
343 	printk("Vcc Maximum: %2d.%d V\n", cfip->VccMax >> 4, cfip->VccMax & 0xf);
344 	if (cfip->VppMin) {
345 		printk("Vpp Minimum: %2d.%d V\n", cfip->VppMin >> 4, cfip->VppMin & 0xf);
346 		printk("Vpp Maximum: %2d.%d V\n", cfip->VppMax >> 4, cfip->VppMax & 0xf);
347 	}
348 	else
349 		printk("No Vpp line\n");
350 
351 	printk("Typical byte/word write timeout: %d µs\n", 1<<cfip->WordWriteTimeoutTyp);
352 	printk("Maximum byte/word write timeout: %d µs\n", (1<<cfip->WordWriteTimeoutMax) * (1<<cfip->WordWriteTimeoutTyp));
353 
354 	if (cfip->BufWriteTimeoutTyp || cfip->BufWriteTimeoutMax) {
355 		printk("Typical full buffer write timeout: %d µs\n", 1<<cfip->BufWriteTimeoutTyp);
356 		printk("Maximum full buffer write timeout: %d µs\n", (1<<cfip->BufWriteTimeoutMax) * (1<<cfip->BufWriteTimeoutTyp));
357 	}
358 	else
359 		printk("Full buffer write not supported\n");
360 
361 	printk("Typical block erase timeout: %d ms\n", 1<<cfip->BlockEraseTimeoutTyp);
362 	printk("Maximum block erase timeout: %d ms\n", (1<<cfip->BlockEraseTimeoutMax) * (1<<cfip->BlockEraseTimeoutTyp));
363 	if (cfip->ChipEraseTimeoutTyp || cfip->ChipEraseTimeoutMax) {
364 		printk("Typical chip erase timeout: %d ms\n", 1<<cfip->ChipEraseTimeoutTyp);
365 		printk("Maximum chip erase timeout: %d ms\n", (1<<cfip->ChipEraseTimeoutMax) * (1<<cfip->ChipEraseTimeoutTyp));
366 	}
367 	else
368 		printk("Chip erase not supported\n");
369 
370 	printk("Device size: 0x%X bytes (%d MiB)\n", 1 << cfip->DevSize, 1<< (cfip->DevSize - 20));
371 	printk("Flash Device Interface description: 0x%4.4X\n", cfip->InterfaceDesc);
372 	switch(cfip->InterfaceDesc) {
373 	case 0:
374 		printk("  - x8-only asynchronous interface\n");
375 		break;
376 
377 	case 1:
378 		printk("  - x16-only asynchronous interface\n");
379 		break;
380 
381 	case 2:
382 		printk("  - supports x8 and x16 via BYTE# with asynchronous interface\n");
383 		break;
384 
385 	case 3:
386 		printk("  - x32-only asynchronous interface\n");
387 		break;
388 
389 	case 4:
390 		printk("  - supports x16 and x32 via Word# with asynchronous interface\n");
391 		break;
392 
393 	case 65535:
394 		printk("  - Not Allowed / Reserved\n");
395 		break;
396 
397 	default:
398 		printk("  - Unknown\n");
399 		break;
400 	}
401 
402 	printk("Max. bytes in buffer write: 0x%x\n", 1<< cfip->MaxBufWriteSize);
403 	printk("Number of Erase Block Regions: %d\n", cfip->NumEraseRegions);
404 
405 }
406 #endif /* DEBUG_CFI */
407 
408 static struct chip_probe cfi_chip_probe = {
409 	.name		= "CFI",
410 	.probe_chip	= cfi_probe_chip
411 };
412 
413 struct mtd_info *cfi_probe(struct map_info *map)
414 {
415 	/*
416 	 * Just use the generic probe stuff to call our CFI-specific
417 	 * chip_probe routine in all the possible permutations, etc.
418 	 */
419 	return mtd_do_chip_probe(map, &cfi_chip_probe);
420 }
421 
422 static struct mtd_chip_driver cfi_chipdrv = {
423 	.probe		= cfi_probe,
424 	.name		= "cfi_probe",
425 	.module		= THIS_MODULE
426 };
427 
428 static int __init cfi_probe_init(void)
429 {
430 	register_mtd_chip_driver(&cfi_chipdrv);
431 	return 0;
432 }
433 
434 static void __exit cfi_probe_exit(void)
435 {
436 	unregister_mtd_chip_driver(&cfi_chipdrv);
437 }
438 
439 module_init(cfi_probe_init);
440 module_exit(cfi_probe_exit);
441 
442 MODULE_LICENSE("GPL");
443 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org> et al.");
444 MODULE_DESCRIPTION("Probe code for CFI-compliant flash chips");
445