1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Common Flash Interface support:
4 * Generic utility functions not dependent on command set
5 *
6 * Copyright (C) 2002 Red Hat
7 * Copyright (C) 2003 STMicroelectronics Limited
8 */
9
10 #include <linux/module.h>
11 #include <linux/types.h>
12 #include <linux/kernel.h>
13 #include <asm/io.h>
14 #include <asm/byteorder.h>
15
16 #include <linux/errno.h>
17 #include <linux/slab.h>
18 #include <linux/delay.h>
19 #include <linux/interrupt.h>
20 #include <linux/mtd/xip.h>
21 #include <linux/mtd/mtd.h>
22 #include <linux/mtd/map.h>
23 #include <linux/mtd/cfi.h>
24
cfi_udelay(int us)25 void cfi_udelay(int us)
26 {
27 if (us >= 1000) {
28 msleep(DIV_ROUND_UP(us, 1000));
29 } else {
30 udelay(us);
31 cond_resched();
32 }
33 }
34 EXPORT_SYMBOL(cfi_udelay);
35
36 /*
37 * Returns the command address according to the given geometry.
38 */
cfi_build_cmd_addr(uint32_t cmd_ofs,struct map_info * map,struct cfi_private * cfi)39 uint32_t cfi_build_cmd_addr(uint32_t cmd_ofs,
40 struct map_info *map, struct cfi_private *cfi)
41 {
42 unsigned bankwidth = map_bankwidth(map);
43 unsigned interleave = cfi_interleave(cfi);
44 unsigned type = cfi->device_type;
45 uint32_t addr;
46
47 addr = (cmd_ofs * type) * interleave;
48
49 /* Modify the unlock address if we are in compatibility mode.
50 * For 16bit devices on 8 bit busses
51 * and 32bit devices on 16 bit busses
52 * set the low bit of the alternating bit sequence of the address.
53 */
54 if (((type * interleave) > bankwidth) && ((cmd_ofs & 0xff) == 0xaa))
55 addr |= (type >> 1)*interleave;
56
57 return addr;
58 }
59 EXPORT_SYMBOL(cfi_build_cmd_addr);
60
61 /*
62 * Transforms the CFI command for the given geometry (bus width & interleave).
63 * It looks too long to be inline, but in the common case it should almost all
64 * get optimised away.
65 */
cfi_build_cmd(u_long cmd,struct map_info * map,struct cfi_private * cfi)66 map_word cfi_build_cmd(u_long cmd, struct map_info *map, struct cfi_private *cfi)
67 {
68 map_word val = { {0} };
69 int wordwidth, words_per_bus, chip_mode, chips_per_word;
70 unsigned long onecmd;
71 int i;
72
73 /* We do it this way to give the compiler a fighting chance
74 of optimising away all the crap for 'bankwidth' larger than
75 an unsigned long, in the common case where that support is
76 disabled */
77 if (map_bankwidth_is_large(map)) {
78 wordwidth = sizeof(unsigned long);
79 words_per_bus = (map_bankwidth(map)) / wordwidth; // i.e. normally 1
80 } else {
81 wordwidth = map_bankwidth(map);
82 words_per_bus = 1;
83 }
84
85 chip_mode = map_bankwidth(map) / cfi_interleave(cfi);
86 chips_per_word = wordwidth * cfi_interleave(cfi) / map_bankwidth(map);
87
88 /* First, determine what the bit-pattern should be for a single
89 device, according to chip mode and endianness... */
90 switch (chip_mode) {
91 default: BUG();
92 case 1:
93 onecmd = cmd;
94 break;
95 case 2:
96 onecmd = cpu_to_cfi16(map, cmd);
97 break;
98 case 4:
99 onecmd = cpu_to_cfi32(map, cmd);
100 break;
101 }
102
103 /* Now replicate it across the size of an unsigned long, or
104 just to the bus width as appropriate */
105 switch (chips_per_word) {
106 default: BUG();
107 #if BITS_PER_LONG >= 64
108 case 8:
109 onecmd |= (onecmd << (chip_mode * 32));
110 fallthrough;
111 #endif
112 case 4:
113 onecmd |= (onecmd << (chip_mode * 16));
114 fallthrough;
115 case 2:
116 onecmd |= (onecmd << (chip_mode * 8));
117 fallthrough;
118 case 1:
119 ;
120 }
121
122 /* And finally, for the multi-word case, replicate it
123 in all words in the structure */
124 for (i=0; i < words_per_bus; i++) {
125 val.x[i] = onecmd;
126 }
127
128 return val;
129 }
130 EXPORT_SYMBOL(cfi_build_cmd);
131
cfi_merge_status(map_word val,struct map_info * map,struct cfi_private * cfi)132 unsigned long cfi_merge_status(map_word val, struct map_info *map,
133 struct cfi_private *cfi)
134 {
135 int wordwidth, words_per_bus, chip_mode, chips_per_word;
136 unsigned long onestat, res = 0;
137 int i;
138
139 /* We do it this way to give the compiler a fighting chance
140 of optimising away all the crap for 'bankwidth' larger than
141 an unsigned long, in the common case where that support is
142 disabled */
143 if (map_bankwidth_is_large(map)) {
144 wordwidth = sizeof(unsigned long);
145 words_per_bus = (map_bankwidth(map)) / wordwidth; // i.e. normally 1
146 } else {
147 wordwidth = map_bankwidth(map);
148 words_per_bus = 1;
149 }
150
151 chip_mode = map_bankwidth(map) / cfi_interleave(cfi);
152 chips_per_word = wordwidth * cfi_interleave(cfi) / map_bankwidth(map);
153
154 onestat = val.x[0];
155 /* Or all status words together */
156 for (i=1; i < words_per_bus; i++) {
157 onestat |= val.x[i];
158 }
159
160 res = onestat;
161 switch(chips_per_word) {
162 default: BUG();
163 #if BITS_PER_LONG >= 64
164 case 8:
165 res |= (onestat >> (chip_mode * 32));
166 fallthrough;
167 #endif
168 case 4:
169 res |= (onestat >> (chip_mode * 16));
170 fallthrough;
171 case 2:
172 res |= (onestat >> (chip_mode * 8));
173 fallthrough;
174 case 1:
175 ;
176 }
177
178 /* Last, determine what the bit-pattern should be for a single
179 device, according to chip mode and endianness... */
180 switch (chip_mode) {
181 case 1:
182 break;
183 case 2:
184 res = cfi16_to_cpu(map, res);
185 break;
186 case 4:
187 res = cfi32_to_cpu(map, res);
188 break;
189 default: BUG();
190 }
191 return res;
192 }
193 EXPORT_SYMBOL(cfi_merge_status);
194
195 /*
196 * Sends a CFI command to a bank of flash for the given geometry.
197 *
198 * Returns the offset in flash where the command was written.
199 * If prev_val is non-null, it will be set to the value at the command address,
200 * before the command was written.
201 */
cfi_send_gen_cmd(u_char cmd,uint32_t cmd_addr,uint32_t base,struct map_info * map,struct cfi_private * cfi,int type,map_word * prev_val)202 uint32_t cfi_send_gen_cmd(u_char cmd, uint32_t cmd_addr, uint32_t base,
203 struct map_info *map, struct cfi_private *cfi,
204 int type, map_word *prev_val)
205 {
206 map_word val;
207 uint32_t addr = base + cfi_build_cmd_addr(cmd_addr, map, cfi);
208 val = cfi_build_cmd(cmd, map, cfi);
209
210 if (prev_val)
211 *prev_val = map_read(map, addr);
212
213 map_write(map, val, addr);
214
215 return addr - base;
216 }
217 EXPORT_SYMBOL(cfi_send_gen_cmd);
218
cfi_qry_present(struct map_info * map,__u32 base,struct cfi_private * cfi)219 int __xipram cfi_qry_present(struct map_info *map, __u32 base,
220 struct cfi_private *cfi)
221 {
222 int osf = cfi->interleave * cfi->device_type; /* scale factor */
223 map_word val[3];
224 map_word qry[3];
225
226 qry[0] = cfi_build_cmd('Q', map, cfi);
227 qry[1] = cfi_build_cmd('R', map, cfi);
228 qry[2] = cfi_build_cmd('Y', map, cfi);
229
230 val[0] = map_read(map, base + osf*0x10);
231 val[1] = map_read(map, base + osf*0x11);
232 val[2] = map_read(map, base + osf*0x12);
233
234 if (!map_word_equal(map, qry[0], val[0]))
235 return 0;
236
237 if (!map_word_equal(map, qry[1], val[1]))
238 return 0;
239
240 if (!map_word_equal(map, qry[2], val[2]))
241 return 0;
242
243 return 1; /* "QRY" found */
244 }
245 EXPORT_SYMBOL_GPL(cfi_qry_present);
246
cfi_qry_mode_on(uint32_t base,struct map_info * map,struct cfi_private * cfi)247 int __xipram cfi_qry_mode_on(uint32_t base, struct map_info *map,
248 struct cfi_private *cfi)
249 {
250 cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
251 cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);
252 if (cfi_qry_present(map, base, cfi))
253 return 1;
254 /* QRY not found probably we deal with some odd CFI chips */
255 /* Some revisions of some old Intel chips? */
256 cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
257 cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
258 cfi_send_gen_cmd(0x98, 0x55, base, map, cfi, cfi->device_type, NULL);
259 if (cfi_qry_present(map, base, cfi))
260 return 1;
261 /* ST M29DW chips */
262 cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
263 cfi_send_gen_cmd(0x98, 0x555, base, map, cfi, cfi->device_type, NULL);
264 if (cfi_qry_present(map, base, cfi))
265 return 1;
266 /* some old SST chips, e.g. 39VF160x/39VF320x */
267 cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
268 cfi_send_gen_cmd(0xAA, 0x5555, base, map, cfi, cfi->device_type, NULL);
269 cfi_send_gen_cmd(0x55, 0x2AAA, base, map, cfi, cfi->device_type, NULL);
270 cfi_send_gen_cmd(0x98, 0x5555, base, map, cfi, cfi->device_type, NULL);
271 if (cfi_qry_present(map, base, cfi))
272 return 1;
273 /* SST 39VF640xB */
274 cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
275 cfi_send_gen_cmd(0xAA, 0x555, base, map, cfi, cfi->device_type, NULL);
276 cfi_send_gen_cmd(0x55, 0x2AA, base, map, cfi, cfi->device_type, NULL);
277 cfi_send_gen_cmd(0x98, 0x555, base, map, cfi, cfi->device_type, NULL);
278 if (cfi_qry_present(map, base, cfi))
279 return 1;
280 /* QRY not found */
281 return 0;
282 }
283 EXPORT_SYMBOL_GPL(cfi_qry_mode_on);
284
cfi_qry_mode_off(uint32_t base,struct map_info * map,struct cfi_private * cfi)285 void __xipram cfi_qry_mode_off(uint32_t base, struct map_info *map,
286 struct cfi_private *cfi)
287 {
288 cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
289 cfi_send_gen_cmd(0xFF, 0, base, map, cfi, cfi->device_type, NULL);
290 /* M29W128G flashes require an additional reset command
291 when exit qry mode */
292 if ((cfi->mfr == CFI_MFR_ST) && (cfi->id == 0x227E || cfi->id == 0x7E))
293 cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
294 }
295 EXPORT_SYMBOL_GPL(cfi_qry_mode_off);
296
297 struct cfi_extquery *
cfi_read_pri(struct map_info * map,__u16 adr,__u16 size,const char * name)298 __xipram cfi_read_pri(struct map_info *map, __u16 adr, __u16 size, const char* name)
299 {
300 struct cfi_private *cfi = map->fldrv_priv;
301 __u32 base = 0; // cfi->chips[0].start;
302 int ofs_factor = cfi->interleave * cfi->device_type;
303 int i;
304 struct cfi_extquery *extp = NULL;
305
306 if (!adr)
307 goto out;
308
309 printk(KERN_INFO "%s Extended Query Table at 0x%4.4X\n", name, adr);
310
311 extp = kmalloc(size, GFP_KERNEL);
312 if (!extp)
313 goto out;
314
315 #ifdef CONFIG_MTD_XIP
316 local_irq_disable();
317 #endif
318
319 /* Switch it into Query Mode */
320 cfi_qry_mode_on(base, map, cfi);
321 /* Read in the Extended Query Table */
322 for (i=0; i<size; i++) {
323 ((unsigned char *)extp)[i] =
324 cfi_read_query(map, base+((adr+i)*ofs_factor));
325 }
326
327 /* Make sure it returns to read mode */
328 cfi_qry_mode_off(base, map, cfi);
329
330 #ifdef CONFIG_MTD_XIP
331 (void) map_read(map, base);
332 xip_iprefetch();
333 local_irq_enable();
334 #endif
335
336 out: return extp;
337 }
338
339 EXPORT_SYMBOL(cfi_read_pri);
340
cfi_fixup(struct mtd_info * mtd,struct cfi_fixup * fixups)341 void cfi_fixup(struct mtd_info *mtd, struct cfi_fixup *fixups)
342 {
343 struct map_info *map = mtd->priv;
344 struct cfi_private *cfi = map->fldrv_priv;
345 struct cfi_fixup *f;
346
347 for (f=fixups; f->fixup; f++) {
348 if (((f->mfr == CFI_MFR_ANY) || (f->mfr == cfi->mfr)) &&
349 ((f->id == CFI_ID_ANY) || (f->id == cfi->id))) {
350 f->fixup(mtd);
351 }
352 }
353 }
354
355 EXPORT_SYMBOL(cfi_fixup);
356
cfi_varsize_frob(struct mtd_info * mtd,varsize_frob_t frob,loff_t ofs,size_t len,void * thunk)357 int cfi_varsize_frob(struct mtd_info *mtd, varsize_frob_t frob,
358 loff_t ofs, size_t len, void *thunk)
359 {
360 struct map_info *map = mtd->priv;
361 struct cfi_private *cfi = map->fldrv_priv;
362 unsigned long adr;
363 int chipnum, ret = 0;
364 int i, first;
365 struct mtd_erase_region_info *regions = mtd->eraseregions;
366
367 /* Check that both start and end of the requested erase are
368 * aligned with the erasesize at the appropriate addresses.
369 */
370
371 i = 0;
372
373 /* Skip all erase regions which are ended before the start of
374 the requested erase. Actually, to save on the calculations,
375 we skip to the first erase region which starts after the
376 start of the requested erase, and then go back one.
377 */
378
379 while (i < mtd->numeraseregions && ofs >= regions[i].offset)
380 i++;
381 i--;
382
383 /* OK, now i is pointing at the erase region in which this
384 erase request starts. Check the start of the requested
385 erase range is aligned with the erase size which is in
386 effect here.
387 */
388
389 if (ofs & (regions[i].erasesize-1))
390 return -EINVAL;
391
392 /* Remember the erase region we start on */
393 first = i;
394
395 /* Next, check that the end of the requested erase is aligned
396 * with the erase region at that address.
397 */
398
399 while (i<mtd->numeraseregions && (ofs + len) >= regions[i].offset)
400 i++;
401
402 /* As before, drop back one to point at the region in which
403 the address actually falls
404 */
405 i--;
406
407 if ((ofs + len) & (regions[i].erasesize-1))
408 return -EINVAL;
409
410 chipnum = ofs >> cfi->chipshift;
411 adr = ofs - (chipnum << cfi->chipshift);
412
413 i=first;
414
415 while(len) {
416 int size = regions[i].erasesize;
417
418 ret = (*frob)(map, &cfi->chips[chipnum], adr, size, thunk);
419
420 if (ret)
421 return ret;
422
423 adr += size;
424 ofs += size;
425 len -= size;
426
427 if (ofs == regions[i].offset + size * regions[i].numblocks)
428 i++;
429
430 if (adr >> cfi->chipshift) {
431 adr = 0;
432 chipnum++;
433
434 if (chipnum >= cfi->numchips)
435 break;
436 }
437 }
438
439 return 0;
440 }
441
442 EXPORT_SYMBOL(cfi_varsize_frob);
443
444 MODULE_LICENSE("GPL");
445