xref: /openbmc/linux/drivers/mtd/chips/cfi_probe.c (revision feac8c8b)
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 /* check for QRY.
67    in: interleave,type,mode
68    ret: table index, <0 for error
69  */
70 
71 static int __xipram cfi_probe_chip(struct map_info *map, __u32 base,
72 				   unsigned long *chip_map, struct cfi_private *cfi)
73 {
74 	int i;
75 
76 	if ((base + 0) >= map->size) {
77 		printk(KERN_NOTICE
78 			"Probe at base[0x00](0x%08lx) past the end of the map(0x%08lx)\n",
79 			(unsigned long)base, map->size -1);
80 		return 0;
81 	}
82 	if ((base + 0xff) >= map->size) {
83 		printk(KERN_NOTICE
84 			"Probe at base[0x55](0x%08lx) past the end of the map(0x%08lx)\n",
85 			(unsigned long)base + 0x55, map->size -1);
86 		return 0;
87 	}
88 
89 	xip_disable();
90 	if (!cfi_qry_mode_on(base, map, cfi)) {
91 		xip_enable(base, map, cfi);
92 		return 0;
93 	}
94 
95 	if (!cfi->numchips) {
96 		/* This is the first time we're called. Set up the CFI
97 		   stuff accordingly and return */
98 		return cfi_chip_setup(map, cfi);
99 	}
100 
101 	/* Check each previous chip to see if it's an alias */
102  	for (i=0; i < (base >> cfi->chipshift); i++) {
103  		unsigned long start;
104  		if(!test_bit(i, chip_map)) {
105 			/* Skip location; no valid chip at this address */
106  			continue;
107  		}
108  		start = i << cfi->chipshift;
109 		/* This chip should be in read mode if it's one
110 		   we've already touched. */
111 		if (cfi_qry_present(map, start, cfi)) {
112 			/* Eep. This chip also had the QRY marker.
113 			 * Is it an alias for the new one? */
114 			cfi_qry_mode_off(start, map, cfi);
115 
116 			/* If the QRY marker goes away, it's an alias */
117 			if (!cfi_qry_present(map, start, cfi)) {
118 				xip_allowed(base, map);
119 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
120 				       map->name, base, start);
121 				return 0;
122 			}
123 			/* Yes, it's actually got QRY for data. Most
124 			 * unfortunate. Stick the new chip in read mode
125 			 * too and if it's the same, assume it's an alias. */
126 			/* FIXME: Use other modes to do a proper check */
127 			cfi_qry_mode_off(base, map, cfi);
128 
129 			if (cfi_qry_present(map, base, cfi)) {
130 				xip_allowed(base, map);
131 				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
132 				       map->name, base, start);
133 				return 0;
134 			}
135 		}
136 	}
137 
138 	/* OK, if we got to here, then none of the previous chips appear to
139 	   be aliases for the current one. */
140 	set_bit((base >> cfi->chipshift), chip_map); /* Update chip map */
141 	cfi->numchips++;
142 
143 	/* Put it back into Read Mode */
144 	cfi_qry_mode_off(base, map, cfi);
145 	xip_allowed(base, map);
146 
147 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
148 	       map->name, cfi->interleave, cfi->device_type*8, base,
149 	       map->bankwidth*8);
150 
151 	return 1;
152 }
153 
154 static int __xipram cfi_chip_setup(struct map_info *map,
155 				   struct cfi_private *cfi)
156 {
157 	int ofs_factor = cfi->interleave*cfi->device_type;
158 	__u32 base = 0;
159 	int num_erase_regions = cfi_read_query(map, base + (0x10 + 28)*ofs_factor);
160 	int i;
161 	int addr_unlock1 = 0x555, addr_unlock2 = 0x2AA;
162 
163 	xip_enable(base, map, cfi);
164 #ifdef DEBUG_CFI
165 	printk("Number of erase regions: %d\n", num_erase_regions);
166 #endif
167 	if (!num_erase_regions)
168 		return 0;
169 
170 	cfi->cfiq = kmalloc(sizeof(struct cfi_ident) + num_erase_regions * 4, GFP_KERNEL);
171 	if (!cfi->cfiq)
172 		return 0;
173 
174 	memset(cfi->cfiq,0,sizeof(struct cfi_ident));
175 
176 	cfi->cfi_mode = CFI_MODE_CFI;
177 
178 	cfi->sector_erase_cmd = CMD(0x30);
179 
180 	/* Read the CFI info structure */
181 	xip_disable_qry(base, map, cfi);
182 	for (i=0; i<(sizeof(struct cfi_ident) + num_erase_regions * 4); i++)
183 		((unsigned char *)cfi->cfiq)[i] = cfi_read_query(map,base + (0x10 + i)*ofs_factor);
184 
185 	/* Do any necessary byteswapping */
186 	cfi->cfiq->P_ID = le16_to_cpu(cfi->cfiq->P_ID);
187 
188 	cfi->cfiq->P_ADR = le16_to_cpu(cfi->cfiq->P_ADR);
189 	cfi->cfiq->A_ID = le16_to_cpu(cfi->cfiq->A_ID);
190 	cfi->cfiq->A_ADR = le16_to_cpu(cfi->cfiq->A_ADR);
191 	cfi->cfiq->InterfaceDesc = le16_to_cpu(cfi->cfiq->InterfaceDesc);
192 	cfi->cfiq->MaxBufWriteSize = le16_to_cpu(cfi->cfiq->MaxBufWriteSize);
193 
194 #ifdef DEBUG_CFI
195 	/* Dump the information therein */
196 	print_cfi_ident(cfi->cfiq);
197 #endif
198 
199 	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
200 		cfi->cfiq->EraseRegionInfo[i] = le32_to_cpu(cfi->cfiq->EraseRegionInfo[i]);
201 
202 #ifdef DEBUG_CFI
203 		printk("  Erase Region #%d: BlockSize 0x%4.4X bytes, %d blocks\n",
204 		       i, (cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff,
205 		       (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1);
206 #endif
207 	}
208 
209 	if (cfi->cfiq->P_ID == P_ID_SST_OLD) {
210 		addr_unlock1 = 0x5555;
211 		addr_unlock2 = 0x2AAA;
212 	}
213 
214 	/*
215 	 * Note we put the device back into Read Mode BEFORE going into Auto
216 	 * Select Mode, as some devices support nesting of modes, others
217 	 * don't. This way should always work.
218 	 * On cmdset 0001 the writes of 0xaa and 0x55 are not needed, and
219 	 * so should be treated as nops or illegal (and so put the device
220 	 * back into Read Mode, which is a nop in this case).
221 	 */
222 	cfi_send_gen_cmd(0xf0,     0, base, map, cfi, cfi->device_type, NULL);
223 	cfi_send_gen_cmd(0xaa, addr_unlock1, base, map, cfi, cfi->device_type, NULL);
224 	cfi_send_gen_cmd(0x55, addr_unlock2, base, map, cfi, cfi->device_type, NULL);
225 	cfi_send_gen_cmd(0x90, addr_unlock1, base, map, cfi, cfi->device_type, NULL);
226 	cfi->mfr = cfi_read_query16(map, base);
227 	cfi->id = cfi_read_query16(map, base + ofs_factor);
228 
229 	/* Get AMD/Spansion extended JEDEC ID */
230 	if (cfi->mfr == CFI_MFR_AMD && (cfi->id & 0xff) == 0x7e)
231 		cfi->id = cfi_read_query(map, base + 0xe * ofs_factor) << 8 |
232 			  cfi_read_query(map, base + 0xf * ofs_factor);
233 
234 	/* Put it back into Read Mode */
235 	cfi_qry_mode_off(base, map, cfi);
236 	xip_allowed(base, map);
237 
238 	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank. Manufacturer ID %#08x Chip ID %#08x\n",
239 	       map->name, cfi->interleave, cfi->device_type*8, base,
240 	       map->bankwidth*8, cfi->mfr, cfi->id);
241 
242 	return 1;
243 }
244 
245 #ifdef DEBUG_CFI
246 static char *vendorname(__u16 vendor)
247 {
248 	switch (vendor) {
249 	case P_ID_NONE:
250 		return "None";
251 
252 	case P_ID_INTEL_EXT:
253 		return "Intel/Sharp Extended";
254 
255 	case P_ID_AMD_STD:
256 		return "AMD/Fujitsu Standard";
257 
258 	case P_ID_INTEL_STD:
259 		return "Intel/Sharp Standard";
260 
261 	case P_ID_AMD_EXT:
262 		return "AMD/Fujitsu Extended";
263 
264 	case P_ID_WINBOND:
265 		return "Winbond Standard";
266 
267 	case P_ID_ST_ADV:
268 		return "ST Advanced";
269 
270 	case P_ID_MITSUBISHI_STD:
271 		return "Mitsubishi Standard";
272 
273 	case P_ID_MITSUBISHI_EXT:
274 		return "Mitsubishi Extended";
275 
276 	case P_ID_SST_PAGE:
277 		return "SST Page Write";
278 
279 	case P_ID_SST_OLD:
280 		return "SST 39VF160x/39VF320x";
281 
282 	case P_ID_INTEL_PERFORMANCE:
283 		return "Intel Performance Code";
284 
285 	case P_ID_INTEL_DATA:
286 		return "Intel Data";
287 
288 	case P_ID_RESERVED:
289 		return "Not Allowed / Reserved for Future Use";
290 
291 	default:
292 		return "Unknown";
293 	}
294 }
295 
296 
297 static void print_cfi_ident(struct cfi_ident *cfip)
298 {
299 #if 0
300 	if (cfip->qry[0] != 'Q' || cfip->qry[1] != 'R' || cfip->qry[2] != 'Y') {
301 		printk("Invalid CFI ident structure.\n");
302 		return;
303 	}
304 #endif
305 	printk("Primary Vendor Command Set: %4.4X (%s)\n", cfip->P_ID, vendorname(cfip->P_ID));
306 	if (cfip->P_ADR)
307 		printk("Primary Algorithm Table at %4.4X\n", cfip->P_ADR);
308 	else
309 		printk("No Primary Algorithm Table\n");
310 
311 	printk("Alternative Vendor Command Set: %4.4X (%s)\n", cfip->A_ID, vendorname(cfip->A_ID));
312 	if (cfip->A_ADR)
313 		printk("Alternate Algorithm Table at %4.4X\n", cfip->A_ADR);
314 	else
315 		printk("No Alternate Algorithm Table\n");
316 
317 
318 	printk("Vcc Minimum: %2d.%d V\n", cfip->VccMin >> 4, cfip->VccMin & 0xf);
319 	printk("Vcc Maximum: %2d.%d V\n", cfip->VccMax >> 4, cfip->VccMax & 0xf);
320 	if (cfip->VppMin) {
321 		printk("Vpp Minimum: %2d.%d V\n", cfip->VppMin >> 4, cfip->VppMin & 0xf);
322 		printk("Vpp Maximum: %2d.%d V\n", cfip->VppMax >> 4, cfip->VppMax & 0xf);
323 	}
324 	else
325 		printk("No Vpp line\n");
326 
327 	printk("Typical byte/word write timeout: %d µs\n", 1<<cfip->WordWriteTimeoutTyp);
328 	printk("Maximum byte/word write timeout: %d µs\n", (1<<cfip->WordWriteTimeoutMax) * (1<<cfip->WordWriteTimeoutTyp));
329 
330 	if (cfip->BufWriteTimeoutTyp || cfip->BufWriteTimeoutMax) {
331 		printk("Typical full buffer write timeout: %d µs\n", 1<<cfip->BufWriteTimeoutTyp);
332 		printk("Maximum full buffer write timeout: %d µs\n", (1<<cfip->BufWriteTimeoutMax) * (1<<cfip->BufWriteTimeoutTyp));
333 	}
334 	else
335 		printk("Full buffer write not supported\n");
336 
337 	printk("Typical block erase timeout: %d ms\n", 1<<cfip->BlockEraseTimeoutTyp);
338 	printk("Maximum block erase timeout: %d ms\n", (1<<cfip->BlockEraseTimeoutMax) * (1<<cfip->BlockEraseTimeoutTyp));
339 	if (cfip->ChipEraseTimeoutTyp || cfip->ChipEraseTimeoutMax) {
340 		printk("Typical chip erase timeout: %d ms\n", 1<<cfip->ChipEraseTimeoutTyp);
341 		printk("Maximum chip erase timeout: %d ms\n", (1<<cfip->ChipEraseTimeoutMax) * (1<<cfip->ChipEraseTimeoutTyp));
342 	}
343 	else
344 		printk("Chip erase not supported\n");
345 
346 	printk("Device size: 0x%X bytes (%d MiB)\n", 1 << cfip->DevSize, 1<< (cfip->DevSize - 20));
347 	printk("Flash Device Interface description: 0x%4.4X\n", cfip->InterfaceDesc);
348 	switch(cfip->InterfaceDesc) {
349 	case CFI_INTERFACE_X8_ASYNC:
350 		printk("  - x8-only asynchronous interface\n");
351 		break;
352 
353 	case CFI_INTERFACE_X16_ASYNC:
354 		printk("  - x16-only asynchronous interface\n");
355 		break;
356 
357 	case CFI_INTERFACE_X8_BY_X16_ASYNC:
358 		printk("  - supports x8 and x16 via BYTE# with asynchronous interface\n");
359 		break;
360 
361 	case CFI_INTERFACE_X32_ASYNC:
362 		printk("  - x32-only asynchronous interface\n");
363 		break;
364 
365 	case CFI_INTERFACE_X16_BY_X32_ASYNC:
366 		printk("  - supports x16 and x32 via Word# with asynchronous interface\n");
367 		break;
368 
369 	case CFI_INTERFACE_NOT_ALLOWED:
370 		printk("  - Not Allowed / Reserved\n");
371 		break;
372 
373 	default:
374 		printk("  - Unknown\n");
375 		break;
376 	}
377 
378 	printk("Max. bytes in buffer write: 0x%x\n", 1<< cfip->MaxBufWriteSize);
379 	printk("Number of Erase Block Regions: %d\n", cfip->NumEraseRegions);
380 
381 }
382 #endif /* DEBUG_CFI */
383 
384 static struct chip_probe cfi_chip_probe = {
385 	.name		= "CFI",
386 	.probe_chip	= cfi_probe_chip
387 };
388 
389 struct mtd_info *cfi_probe(struct map_info *map)
390 {
391 	/*
392 	 * Just use the generic probe stuff to call our CFI-specific
393 	 * chip_probe routine in all the possible permutations, etc.
394 	 */
395 	return mtd_do_chip_probe(map, &cfi_chip_probe);
396 }
397 
398 static struct mtd_chip_driver cfi_chipdrv = {
399 	.probe		= cfi_probe,
400 	.name		= "cfi_probe",
401 	.module		= THIS_MODULE
402 };
403 
404 static int __init cfi_probe_init(void)
405 {
406 	register_mtd_chip_driver(&cfi_chipdrv);
407 	return 0;
408 }
409 
410 static void __exit cfi_probe_exit(void)
411 {
412 	unregister_mtd_chip_driver(&cfi_chipdrv);
413 }
414 
415 module_init(cfi_probe_init);
416 module_exit(cfi_probe_exit);
417 
418 MODULE_LICENSE("GPL");
419 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org> et al.");
420 MODULE_DESCRIPTION("Probe code for CFI-compliant flash chips");
421