xref: /linux/drivers/mtd/chips/cfi_util.c (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
1 /*
2  * Common Flash Interface support:
3  *   Generic utility functions not dependent on command set
4  *
5  * Copyright (C) 2002 Red Hat
6  * Copyright (C) 2003 STMicroelectronics Limited
7  *
8  * This code is covered by the GPL.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <asm/io.h>
15 #include <asm/byteorder.h>
16 
17 #include <linux/errno.h>
18 #include <linux/slab.h>
19 #include <linux/delay.h>
20 #include <linux/interrupt.h>
21 #include <linux/mtd/xip.h>
22 #include <linux/mtd/mtd.h>
23 #include <linux/mtd/map.h>
24 #include <linux/mtd/cfi.h>
25 
26 void cfi_udelay(int us)
27 {
28 	if (us >= 1000) {
29 		msleep((us+999)/1000);
30 	} else {
31 		udelay(us);
32 		cond_resched();
33 	}
34 }
35 EXPORT_SYMBOL(cfi_udelay);
36 
37 /*
38  * Returns the command address according to the given geometry.
39  */
40 uint32_t cfi_build_cmd_addr(uint32_t cmd_ofs,
41 				struct map_info *map, struct cfi_private *cfi)
42 {
43 	unsigned bankwidth = map_bankwidth(map);
44 	unsigned interleave = cfi_interleave(cfi);
45 	unsigned type = cfi->device_type;
46 	uint32_t addr;
47 
48 	addr = (cmd_ofs * type) * interleave;
49 
50 	/* Modify the unlock address if we are in compatibility mode.
51 	 * For 16bit devices on 8 bit busses
52 	 * and 32bit devices on 16 bit busses
53 	 * set the low bit of the alternating bit sequence of the address.
54 	 */
55 	if (((type * interleave) > bankwidth) && ((cmd_ofs & 0xff) == 0xaa))
56 		addr |= (type >> 1)*interleave;
57 
58 	return  addr;
59 }
60 EXPORT_SYMBOL(cfi_build_cmd_addr);
61 
62 /*
63  * Transforms the CFI command for the given geometry (bus width & interleave).
64  * It looks too long to be inline, but in the common case it should almost all
65  * get optimised away.
66  */
67 map_word cfi_build_cmd(u_long cmd, struct map_info *map, struct cfi_private *cfi)
68 {
69 	map_word val = { {0} };
70 	int wordwidth, words_per_bus, chip_mode, chips_per_word;
71 	unsigned long onecmd;
72 	int i;
73 
74 	/* We do it this way to give the compiler a fighting chance
75 	   of optimising away all the crap for 'bankwidth' larger than
76 	   an unsigned long, in the common case where that support is
77 	   disabled */
78 	if (map_bankwidth_is_large(map)) {
79 		wordwidth = sizeof(unsigned long);
80 		words_per_bus = (map_bankwidth(map)) / wordwidth; // i.e. normally 1
81 	} else {
82 		wordwidth = map_bankwidth(map);
83 		words_per_bus = 1;
84 	}
85 
86 	chip_mode = map_bankwidth(map) / cfi_interleave(cfi);
87 	chips_per_word = wordwidth * cfi_interleave(cfi) / map_bankwidth(map);
88 
89 	/* First, determine what the bit-pattern should be for a single
90 	   device, according to chip mode and endianness... */
91 	switch (chip_mode) {
92 	default: BUG();
93 	case 1:
94 		onecmd = cmd;
95 		break;
96 	case 2:
97 		onecmd = cpu_to_cfi16(map, cmd);
98 		break;
99 	case 4:
100 		onecmd = cpu_to_cfi32(map, cmd);
101 		break;
102 	}
103 
104 	/* Now replicate it across the size of an unsigned long, or
105 	   just to the bus width as appropriate */
106 	switch (chips_per_word) {
107 	default: BUG();
108 #if BITS_PER_LONG >= 64
109 	case 8:
110 		onecmd |= (onecmd << (chip_mode * 32));
111 #endif
112 	case 4:
113 		onecmd |= (onecmd << (chip_mode * 16));
114 	case 2:
115 		onecmd |= (onecmd << (chip_mode * 8));
116 	case 1:
117 		;
118 	}
119 
120 	/* And finally, for the multi-word case, replicate it
121 	   in all words in the structure */
122 	for (i=0; i < words_per_bus; i++) {
123 		val.x[i] = onecmd;
124 	}
125 
126 	return val;
127 }
128 EXPORT_SYMBOL(cfi_build_cmd);
129 
130 unsigned long cfi_merge_status(map_word val, struct map_info *map,
131 					   struct cfi_private *cfi)
132 {
133 	int wordwidth, words_per_bus, chip_mode, chips_per_word;
134 	unsigned long onestat, res = 0;
135 	int i;
136 
137 	/* We do it this way to give the compiler a fighting chance
138 	   of optimising away all the crap for 'bankwidth' larger than
139 	   an unsigned long, in the common case where that support is
140 	   disabled */
141 	if (map_bankwidth_is_large(map)) {
142 		wordwidth = sizeof(unsigned long);
143 		words_per_bus = (map_bankwidth(map)) / wordwidth; // i.e. normally 1
144 	} else {
145 		wordwidth = map_bankwidth(map);
146 		words_per_bus = 1;
147 	}
148 
149 	chip_mode = map_bankwidth(map) / cfi_interleave(cfi);
150 	chips_per_word = wordwidth * cfi_interleave(cfi) / map_bankwidth(map);
151 
152 	onestat = val.x[0];
153 	/* Or all status words together */
154 	for (i=1; i < words_per_bus; i++) {
155 		onestat |= val.x[i];
156 	}
157 
158 	res = onestat;
159 	switch(chips_per_word) {
160 	default: BUG();
161 #if BITS_PER_LONG >= 64
162 	case 8:
163 		res |= (onestat >> (chip_mode * 32));
164 #endif
165 	case 4:
166 		res |= (onestat >> (chip_mode * 16));
167 	case 2:
168 		res |= (onestat >> (chip_mode * 8));
169 	case 1:
170 		;
171 	}
172 
173 	/* Last, determine what the bit-pattern should be for a single
174 	   device, according to chip mode and endianness... */
175 	switch (chip_mode) {
176 	case 1:
177 		break;
178 	case 2:
179 		res = cfi16_to_cpu(map, res);
180 		break;
181 	case 4:
182 		res = cfi32_to_cpu(map, res);
183 		break;
184 	default: BUG();
185 	}
186 	return res;
187 }
188 EXPORT_SYMBOL(cfi_merge_status);
189 
190 /*
191  * Sends a CFI command to a bank of flash for the given geometry.
192  *
193  * Returns the offset in flash where the command was written.
194  * If prev_val is non-null, it will be set to the value at the command address,
195  * before the command was written.
196  */
197 uint32_t cfi_send_gen_cmd(u_char cmd, uint32_t cmd_addr, uint32_t base,
198 				struct map_info *map, struct cfi_private *cfi,
199 				int type, map_word *prev_val)
200 {
201 	map_word val;
202 	uint32_t addr = base + cfi_build_cmd_addr(cmd_addr, map, cfi);
203 	val = cfi_build_cmd(cmd, map, cfi);
204 
205 	if (prev_val)
206 		*prev_val = map_read(map, addr);
207 
208 	map_write(map, val, addr);
209 
210 	return addr - base;
211 }
212 EXPORT_SYMBOL(cfi_send_gen_cmd);
213 
214 int __xipram cfi_qry_present(struct map_info *map, __u32 base,
215 			     struct cfi_private *cfi)
216 {
217 	int osf = cfi->interleave * cfi->device_type;	/* scale factor */
218 	map_word val[3];
219 	map_word qry[3];
220 
221 	qry[0] = cfi_build_cmd('Q', map, cfi);
222 	qry[1] = cfi_build_cmd('R', map, cfi);
223 	qry[2] = cfi_build_cmd('Y', map, cfi);
224 
225 	val[0] = map_read(map, base + osf*0x10);
226 	val[1] = map_read(map, base + osf*0x11);
227 	val[2] = map_read(map, base + osf*0x12);
228 
229 	if (!map_word_equal(map, qry[0], val[0]))
230 		return 0;
231 
232 	if (!map_word_equal(map, qry[1], val[1]))
233 		return 0;
234 
235 	if (!map_word_equal(map, qry[2], val[2]))
236 		return 0;
237 
238 	return 1; 	/* "QRY" found */
239 }
240 EXPORT_SYMBOL_GPL(cfi_qry_present);
241 
242 int __xipram cfi_qry_mode_on(uint32_t base, struct map_info *map,
243 			     struct cfi_private *cfi)
244 {
245 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
246 	cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);
247 	if (cfi_qry_present(map, base, cfi))
248 		return 1;
249 	/* QRY not found probably we deal with some odd CFI chips */
250 	/* Some revisions of some old Intel chips? */
251 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
252 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
253 	cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);
254 	if (cfi_qry_present(map, base, cfi))
255 		return 1;
256 	/* ST M29DW chips */
257 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
258 	cfi_send_gen_cmd(0x98, 0x555, base, map, cfi, cfi->device_type, NULL);
259 	if (cfi_qry_present(map, base, cfi))
260 		return 1;
261 	/* some old SST chips, e.g. 39VF160x/39VF320x */
262 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
263 	cfi_send_gen_cmd(0xAA, 0x5555, base, map, cfi, cfi->device_type, NULL);
264 	cfi_send_gen_cmd(0x55, 0x2AAA, base, map, cfi, cfi->device_type, NULL);
265 	cfi_send_gen_cmd(0x98, 0x5555, base, map, cfi, cfi->device_type, NULL);
266 	if (cfi_qry_present(map, base, cfi))
267 		return 1;
268 	/* SST 39VF640xB */
269 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
270 	cfi_send_gen_cmd(0xAA, 0x555, base, map, cfi, cfi->device_type, NULL);
271 	cfi_send_gen_cmd(0x55, 0x2AA, base, map, cfi, cfi->device_type, NULL);
272 	cfi_send_gen_cmd(0x98, 0x555, base, map, cfi, cfi->device_type, NULL);
273 	if (cfi_qry_present(map, base, cfi))
274 		return 1;
275 	/* QRY not found */
276 	return 0;
277 }
278 EXPORT_SYMBOL_GPL(cfi_qry_mode_on);
279 
280 void __xipram cfi_qry_mode_off(uint32_t base, struct map_info *map,
281 			       struct cfi_private *cfi)
282 {
283 	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
284 	cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
285 	/* M29W128G flashes require an additional reset command
286 	   when exit qry mode */
287 	if ((cfi->mfr == CFI_MFR_ST) && (cfi->id == 0x227E || cfi->id == 0x7E))
288 		cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
289 }
290 EXPORT_SYMBOL_GPL(cfi_qry_mode_off);
291 
292 struct cfi_extquery *
293 __xipram cfi_read_pri(struct map_info *map, __u16 adr, __u16 size, const char* name)
294 {
295 	struct cfi_private *cfi = map->fldrv_priv;
296 	__u32 base = 0; // cfi->chips[0].start;
297 	int ofs_factor = cfi->interleave * cfi->device_type;
298 	int i;
299 	struct cfi_extquery *extp = NULL;
300 
301 	if (!adr)
302 		goto out;
303 
304 	printk(KERN_INFO "%s Extended Query Table at 0x%4.4X\n", name, adr);
305 
306 	extp = kmalloc(size, GFP_KERNEL);
307 	if (!extp)
308 		goto out;
309 
310 #ifdef CONFIG_MTD_XIP
311 	local_irq_disable();
312 #endif
313 
314 	/* Switch it into Query Mode */
315 	cfi_qry_mode_on(base, map, cfi);
316 	/* Read in the Extended Query Table */
317 	for (i=0; i<size; i++) {
318 		((unsigned char *)extp)[i] =
319 			cfi_read_query(map, base+((adr+i)*ofs_factor));
320 	}
321 
322 	/* Make sure it returns to read mode */
323 	cfi_qry_mode_off(base, map, cfi);
324 
325 #ifdef CONFIG_MTD_XIP
326 	(void) map_read(map, base);
327 	xip_iprefetch();
328 	local_irq_enable();
329 #endif
330 
331  out:	return extp;
332 }
333 
334 EXPORT_SYMBOL(cfi_read_pri);
335 
336 void cfi_fixup(struct mtd_info *mtd, struct cfi_fixup *fixups)
337 {
338 	struct map_info *map = mtd->priv;
339 	struct cfi_private *cfi = map->fldrv_priv;
340 	struct cfi_fixup *f;
341 
342 	for (f=fixups; f->fixup; f++) {
343 		if (((f->mfr == CFI_MFR_ANY) || (f->mfr == cfi->mfr)) &&
344 		    ((f->id  == CFI_ID_ANY)  || (f->id  == cfi->id))) {
345 			f->fixup(mtd);
346 		}
347 	}
348 }
349 
350 EXPORT_SYMBOL(cfi_fixup);
351 
352 int cfi_varsize_frob(struct mtd_info *mtd, varsize_frob_t frob,
353 				     loff_t ofs, size_t len, void *thunk)
354 {
355 	struct map_info *map = mtd->priv;
356 	struct cfi_private *cfi = map->fldrv_priv;
357 	unsigned long adr;
358 	int chipnum, ret = 0;
359 	int i, first;
360 	struct mtd_erase_region_info *regions = mtd->eraseregions;
361 
362 	/* Check that both start and end of the requested erase are
363 	 * aligned with the erasesize at the appropriate addresses.
364 	 */
365 
366 	i = 0;
367 
368 	/* Skip all erase regions which are ended before the start of
369 	   the requested erase. Actually, to save on the calculations,
370 	   we skip to the first erase region which starts after the
371 	   start of the requested erase, and then go back one.
372 	*/
373 
374 	while (i < mtd->numeraseregions && ofs >= regions[i].offset)
375 	       i++;
376 	i--;
377 
378 	/* OK, now i is pointing at the erase region in which this
379 	   erase request starts. Check the start of the requested
380 	   erase range is aligned with the erase size which is in
381 	   effect here.
382 	*/
383 
384 	if (ofs & (regions[i].erasesize-1))
385 		return -EINVAL;
386 
387 	/* Remember the erase region we start on */
388 	first = i;
389 
390 	/* Next, check that the end of the requested erase is aligned
391 	 * with the erase region at that address.
392 	 */
393 
394 	while (i<mtd->numeraseregions && (ofs + len) >= regions[i].offset)
395 		i++;
396 
397 	/* As before, drop back one to point at the region in which
398 	   the address actually falls
399 	*/
400 	i--;
401 
402 	if ((ofs + len) & (regions[i].erasesize-1))
403 		return -EINVAL;
404 
405 	chipnum = ofs >> cfi->chipshift;
406 	adr = ofs - (chipnum << cfi->chipshift);
407 
408 	i=first;
409 
410 	while(len) {
411 		int size = regions[i].erasesize;
412 
413 		ret = (*frob)(map, &cfi->chips[chipnum], adr, size, thunk);
414 
415 		if (ret)
416 			return ret;
417 
418 		adr += size;
419 		ofs += size;
420 		len -= size;
421 
422 		if (ofs == regions[i].offset + size * regions[i].numblocks)
423 			i++;
424 
425 		if (adr >> cfi->chipshift) {
426 			adr = 0;
427 			chipnum++;
428 
429 			if (chipnum >= cfi->numchips)
430 				break;
431 		}
432 	}
433 
434 	return 0;
435 }
436 
437 EXPORT_SYMBOL(cfi_varsize_frob);
438 
439 MODULE_LICENSE("GPL");
440