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 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 */ 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 */ 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); 131 132 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 */ 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); 218 219 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); 246 247 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); 284 285 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 * 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); 340 341 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); 356 357 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