drivers/mtd/nand/raw/bcm47xxnflash/ops_bcm4706.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * BCM47XX NAND flash driver
   4  *
   5  * Copyright (C) 2012 Rafał Miłecki <zajec5@gmail.com>
   6  */
   7
   8 #include "bcm47xxnflash.h"
   9
  10 #include <linux/module.h>
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/delay.h>
  14 #include <linux/bcma/bcma.h>
  15
  16 /* Broadcom uses 1'000'000 but it seems to be too many. Tests on WNDR4500 has
  17  * shown ~1000 retries as maxiumum. */
  18 #define NFLASH_READY_RETRIES            10000
  19
  20 #define NFLASH_SECTOR_SIZE              512
  21
  22 #define NCTL_CMD0                       0x00010000
  23 #define NCTL_COL                        0x00020000      /* Update column with value from BCMA_CC_NFLASH_COL_ADDR */
  24 #define NCTL_ROW                        0x00040000      /* Update row (page) with value from BCMA_CC_NFLASH_ROW_ADDR */
  25 #define NCTL_CMD1W                      0x00080000
  26 #define NCTL_READ                       0x00100000
  27 #define NCTL_WRITE                      0x00200000
  28 #define NCTL_SPECADDR                   0x01000000
  29 #define NCTL_READY                      0x04000000
  30 #define NCTL_ERR                        0x08000000
  31 #define NCTL_CSA                        0x40000000
  32 #define NCTL_START                      0x80000000
  33
  34 /**************************************************
  35  * Various helpers
  36  **************************************************/
  37
  38 static inline u8 bcm47xxnflash_ops_bcm4706_ns_to_cycle(u16 ns, u16 clock)
  39 {
  40         return ((ns * 1000 * clock) / 1000000) + 1;
  41 }
  42
  43 static int bcm47xxnflash_ops_bcm4706_ctl_cmd(struct bcma_drv_cc *cc, u32 code)
  44 {
  45         int i = 0;
  46
  47         bcma_cc_write32(cc, BCMA_CC_NFLASH_CTL, NCTL_START | code);
  48         for (i = 0; i < NFLASH_READY_RETRIES; i++) {
  49                 if (!(bcma_cc_read32(cc, BCMA_CC_NFLASH_CTL) & NCTL_START)) {
  50                         i = 0;
  51                         break;
  52                 }
  53         }
  54         if (i) {
  55                 pr_err("NFLASH control command not ready!\n");
  56                 return -EBUSY;
  57         }
  58         return 0;
  59 }
  60
  61 static int bcm47xxnflash_ops_bcm4706_poll(struct bcma_drv_cc *cc)
  62 {
  63         int i;
  64
  65         for (i = 0; i < NFLASH_READY_RETRIES; i++) {
  66                 if (bcma_cc_read32(cc, BCMA_CC_NFLASH_CTL) & NCTL_READY) {
  67                         if (bcma_cc_read32(cc, BCMA_CC_NFLASH_CTL) &
  68                             BCMA_CC_NFLASH_CTL_ERR) {
  69                                 pr_err("Error on polling\n");
  70                                 return -EBUSY;
  71                         } else {
  72                                 return 0;
  73                         }
  74                 }
  75         }
  76
  77         pr_err("Polling timeout!\n");
  78         return -EBUSY;
  79 }
  80
  81 /**************************************************
  82  * R/W
  83  **************************************************/
  84
  85 static void bcm47xxnflash_ops_bcm4706_read(struct mtd_info *mtd, uint8_t *buf,
  86                                            int len)
  87 {
  88         struct nand_chip *nand_chip = mtd_to_nand(mtd);
  89         struct bcm47xxnflash *b47n = nand_get_controller_data(nand_chip);
  90
  91         u32 ctlcode;
  92         u32 *dest = (u32 *)buf;
  93         int i;
  94         int toread;
  95
  96         BUG_ON(b47n->curr_page_addr & ~nand_chip->pagemask);
  97         /* Don't validate column using nand_chip->page_shift, it may be bigger
  98          * when accessing OOB */
  99
 100         while (len) {
 101                 /* We can read maximum of 0x200 bytes at once */
 102                 toread = min(len, 0x200);
 103
 104                 /* Set page and column */
 105                 bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_COL_ADDR,
 106                                 b47n->curr_column);
 107                 bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_ROW_ADDR,
 108                                 b47n->curr_page_addr);
 109
 110                 /* Prepare to read */
 111                 ctlcode = NCTL_CSA | NCTL_CMD1W | NCTL_ROW | NCTL_COL |
 112                           NCTL_CMD0;
 113                 ctlcode |= NAND_CMD_READSTART << 8;
 114                 if (bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc, ctlcode))
 115                         return;
 116                 if (bcm47xxnflash_ops_bcm4706_poll(b47n->cc))
 117                         return;
 118
 119                 /* Eventually read some data :) */
 120                 for (i = 0; i < toread; i += 4, dest++) {
 121                         ctlcode = NCTL_CSA | 0x30000000 | NCTL_READ;
 122                         if (i == toread - 4) /* Last read goes without that */
 123                                 ctlcode &= ~NCTL_CSA;
 124                         if (bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc,
 125                                                               ctlcode))
 126                                 return;
 127                         *dest = bcma_cc_read32(b47n->cc, BCMA_CC_NFLASH_DATA);
 128                 }
 129
 130                 b47n->curr_column += toread;
 131                 len -= toread;
 132         }
 133 }
 134
 135 static void bcm47xxnflash_ops_bcm4706_write(struct mtd_info *mtd,
 136                                             const uint8_t *buf, int len)
 137 {
 138         struct nand_chip *nand_chip = mtd_to_nand(mtd);
 139         struct bcm47xxnflash *b47n = nand_get_controller_data(nand_chip);
 140         struct bcma_drv_cc *cc = b47n->cc;
 141
 142         u32 ctlcode;
 143         const u32 *data = (u32 *)buf;
 144         int i;
 145
 146         BUG_ON(b47n->curr_page_addr & ~nand_chip->pagemask);
 147         /* Don't validate column using nand_chip->page_shift, it may be bigger
 148          * when accessing OOB */
 149
 150         for (i = 0; i < len; i += 4, data++) {
 151                 bcma_cc_write32(cc, BCMA_CC_NFLASH_DATA, *data);
 152
 153                 ctlcode = NCTL_CSA | 0x30000000 | NCTL_WRITE;
 154                 if (i == len - 4) /* Last read goes without that */
 155                         ctlcode &= ~NCTL_CSA;
 156                 if (bcm47xxnflash_ops_bcm4706_ctl_cmd(cc, ctlcode)) {
 157                         pr_err("%s ctl_cmd didn't work!\n", __func__);
 158                         return;
 159                 }
 160         }
 161
 162         b47n->curr_column += len;
 163 }
 164
 165 /**************************************************
 166  * NAND chip ops
 167  **************************************************/
 168
 169 static void bcm47xxnflash_ops_bcm4706_cmd_ctrl(struct nand_chip *nand_chip,
 170                                                int cmd, unsigned int ctrl)
 171 {
 172         struct bcm47xxnflash *b47n = nand_get_controller_data(nand_chip);
 173         u32 code = 0;
 174
 175         if (cmd == NAND_CMD_NONE)
 176                 return;
 177
 178         if (cmd & NAND_CTRL_CLE)
 179                 code = cmd | NCTL_CMD0;
 180
 181         /* nCS is not needed for reset command */
 182         if (cmd != NAND_CMD_RESET)
 183                 code |= NCTL_CSA;
 184
 185         bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc, code);
 186 }
 187
 188 /* Default nand_select_chip calls cmd_ctrl, which is not used in BCM4706 */
 189 static void bcm47xxnflash_ops_bcm4706_select_chip(struct nand_chip *chip,
 190                                                   int cs)
 191 {
 192         return;
 193 }
 194
 195 static int bcm47xxnflash_ops_bcm4706_dev_ready(struct nand_chip *nand_chip)
 196 {
 197         struct bcm47xxnflash *b47n = nand_get_controller_data(nand_chip);
 198
 199         return !!(bcma_cc_read32(b47n->cc, BCMA_CC_NFLASH_CTL) & NCTL_READY);
 200 }
 201
 202 /*
 203  * Default nand_command and nand_command_lp don't match BCM4706 hardware layout.
 204  * For example, reading chip id is performed in a non-standard way.
 205  * Setting column and page is also handled differently, we use a special
 206  * registers of ChipCommon core. Hacking cmd_ctrl to understand and convert
 207  * standard commands would be much more complicated.
 208  */
 209 static void bcm47xxnflash_ops_bcm4706_cmdfunc(struct nand_chip *nand_chip,
 210                                               unsigned command, int column,
 211                                               int page_addr)
 212 {
 213         struct mtd_info *mtd = nand_to_mtd(nand_chip);
 214         struct bcm47xxnflash *b47n = nand_get_controller_data(nand_chip);
 215         struct bcma_drv_cc *cc = b47n->cc;
 216         u32 ctlcode;
 217         int i;
 218
 219         if (column != -1)
 220                 b47n->curr_column = column;
 221         if (page_addr != -1)
 222                 b47n->curr_page_addr = page_addr;
 223
 224         switch (command) {
 225         case NAND_CMD_RESET:
 226                 nand_chip->legacy.cmd_ctrl(nand_chip, command, NAND_CTRL_CLE);
 227
 228                 ndelay(100);
 229                 nand_wait_ready(nand_chip);
 230                 break;
 231         case NAND_CMD_READID:
 232                 ctlcode = NCTL_CSA | 0x01000000 | NCTL_CMD1W | NCTL_CMD0;
 233                 ctlcode |= NAND_CMD_READID;
 234                 if (bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc, ctlcode)) {
 235                         pr_err("READID error\n");
 236                         break;
 237                 }
 238
 239                 /*
 240                  * Reading is specific, last one has to go without NCTL_CSA
 241                  * bit. We don't know how many reads NAND subsystem is going
 242                  * to perform, so cache everything.
 243                  */
 244                 for (i = 0; i < ARRAY_SIZE(b47n->id_data); i++) {
 245                         ctlcode = NCTL_CSA | NCTL_READ;
 246                         if (i == ARRAY_SIZE(b47n->id_data) - 1)
 247                                 ctlcode &= ~NCTL_CSA;
 248                         if (bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc,
 249                                                               ctlcode)) {
 250                                 pr_err("READID error\n");
 251                                 break;
 252                         }
 253                         b47n->id_data[i] =
 254                                 bcma_cc_read32(b47n->cc, BCMA_CC_NFLASH_DATA)
 255                                 & 0xFF;
 256                 }
 257
 258                 break;
 259         case NAND_CMD_STATUS:
 260                 ctlcode = NCTL_CSA | NCTL_CMD0 | NAND_CMD_STATUS;
 261                 if (bcm47xxnflash_ops_bcm4706_ctl_cmd(cc, ctlcode))
 262                         pr_err("STATUS command error\n");
 263                 break;
 264         case NAND_CMD_READ0:
 265                 break;
 266         case NAND_CMD_READOOB:
 267                 if (page_addr != -1)
 268                         b47n->curr_column += mtd->writesize;
 269                 break;
 270         case NAND_CMD_ERASE1:
 271                 bcma_cc_write32(cc, BCMA_CC_NFLASH_ROW_ADDR,
 272                                 b47n->curr_page_addr);
 273                 ctlcode = NCTL_ROW | NCTL_CMD1W | NCTL_CMD0 |
 274                           NAND_CMD_ERASE1 | (NAND_CMD_ERASE2 << 8);
 275                 if (bcm47xxnflash_ops_bcm4706_ctl_cmd(cc, ctlcode))
 276                         pr_err("ERASE1 failed\n");
 277                 break;
 278         case NAND_CMD_ERASE2:
 279                 break;
 280         case NAND_CMD_SEQIN:
 281                 /* Set page and column */
 282                 bcma_cc_write32(cc, BCMA_CC_NFLASH_COL_ADDR,
 283                                 b47n->curr_column);
 284                 bcma_cc_write32(cc, BCMA_CC_NFLASH_ROW_ADDR,
 285                                 b47n->curr_page_addr);
 286
 287                 /* Prepare to write */
 288                 ctlcode = 0x40000000 | NCTL_ROW | NCTL_COL | NCTL_CMD0;
 289                 ctlcode |= NAND_CMD_SEQIN;
 290                 if (bcm47xxnflash_ops_bcm4706_ctl_cmd(cc, ctlcode))
 291                         pr_err("SEQIN failed\n");
 292                 break;
 293         case NAND_CMD_PAGEPROG:
 294                 if (bcm47xxnflash_ops_bcm4706_ctl_cmd(cc, NCTL_CMD0 |
 295                                                           NAND_CMD_PAGEPROG))
 296                         pr_err("PAGEPROG failed\n");
 297                 if (bcm47xxnflash_ops_bcm4706_poll(cc))
 298                         pr_err("PAGEPROG not ready\n");
 299                 break;
 300         default:
 301                 pr_err("Command 0x%X unsupported\n", command);
 302                 break;
 303         }
 304         b47n->curr_command = command;
 305 }
 306
 307 static u8 bcm47xxnflash_ops_bcm4706_read_byte(struct nand_chip *nand_chip)
 308 {
 309         struct mtd_info *mtd = nand_to_mtd(nand_chip);
 310         struct bcm47xxnflash *b47n = nand_get_controller_data(nand_chip);
 311         struct bcma_drv_cc *cc = b47n->cc;
 312         u32 tmp = 0;
 313
 314         switch (b47n->curr_command) {
 315         case NAND_CMD_READID:
 316                 if (b47n->curr_column >= ARRAY_SIZE(b47n->id_data)) {
 317                         pr_err("Requested invalid id_data: %d\n",
 318                                b47n->curr_column);
 319                         return 0;
 320                 }
 321                 return b47n->id_data[b47n->curr_column++];
 322         case NAND_CMD_STATUS:
 323                 if (bcm47xxnflash_ops_bcm4706_ctl_cmd(cc, NCTL_READ))
 324                         return 0;
 325                 return bcma_cc_read32(cc, BCMA_CC_NFLASH_DATA) & 0xff;
 326         case NAND_CMD_READOOB:
 327                 bcm47xxnflash_ops_bcm4706_read(mtd, (u8 *)&tmp, 4);
 328                 return tmp & 0xFF;
 329         }
 330
 331         pr_err("Invalid command for byte read: 0x%X\n", b47n->curr_command);
 332         return 0;
 333 }
 334
 335 static void bcm47xxnflash_ops_bcm4706_read_buf(struct nand_chip *nand_chip,
 336                                                uint8_t *buf, int len)
 337 {
 338         struct bcm47xxnflash *b47n = nand_get_controller_data(nand_chip);
 339
 340         switch (b47n->curr_command) {
 341         case NAND_CMD_READ0:
 342         case NAND_CMD_READOOB:
 343                 bcm47xxnflash_ops_bcm4706_read(nand_to_mtd(nand_chip), buf,
 344                                                len);
 345                 return;
 346         }
 347
 348         pr_err("Invalid command for buf read: 0x%X\n", b47n->curr_command);
 349 }
 350
 351 static void bcm47xxnflash_ops_bcm4706_write_buf(struct nand_chip *nand_chip,
 352                                                 const uint8_t *buf, int len)
 353 {
 354         struct bcm47xxnflash *b47n = nand_get_controller_data(nand_chip);
 355
 356         switch (b47n->curr_command) {
 357         case NAND_CMD_SEQIN:
 358                 bcm47xxnflash_ops_bcm4706_write(nand_to_mtd(nand_chip), buf,
 359                                                 len);
 360                 return;
 361         }
 362
 363         pr_err("Invalid command for buf write: 0x%X\n", b47n->curr_command);
 364 }
 365
 366 /**************************************************
 367  * Init
 368  **************************************************/
 369
 370 int bcm47xxnflash_ops_bcm4706_init(struct bcm47xxnflash *b47n)
 371 {
 372         struct nand_chip *nand_chip = (struct nand_chip *)&b47n->nand_chip;
 373         int err;
 374         u32 freq;
 375         u16 clock;
 376         u8 w0, w1, w2, w3, w4;
 377
 378         unsigned long chipsize; /* MiB */
 379         u8 tbits, col_bits, col_size, row_bits, row_bsize;
 380         u32 val;
 381
 382         nand_chip->legacy.select_chip = bcm47xxnflash_ops_bcm4706_select_chip;
 383         nand_chip->legacy.cmd_ctrl = bcm47xxnflash_ops_bcm4706_cmd_ctrl;
 384         nand_chip->legacy.dev_ready = bcm47xxnflash_ops_bcm4706_dev_ready;
 385         b47n->nand_chip.legacy.cmdfunc = bcm47xxnflash_ops_bcm4706_cmdfunc;
 386         b47n->nand_chip.legacy.read_byte = bcm47xxnflash_ops_bcm4706_read_byte;
 387         b47n->nand_chip.legacy.read_buf = bcm47xxnflash_ops_bcm4706_read_buf;
 388         b47n->nand_chip.legacy.write_buf = bcm47xxnflash_ops_bcm4706_write_buf;
 389         b47n->nand_chip.legacy.set_features = nand_get_set_features_notsupp;
 390         b47n->nand_chip.legacy.get_features = nand_get_set_features_notsupp;
 391
 392         nand_chip->legacy.chip_delay = 50;
 393         b47n->nand_chip.bbt_options = NAND_BBT_USE_FLASH;
 394         /* TODO: implement ECC */
 395         b47n->nand_chip.ecc.engine_type = NAND_ECC_ENGINE_TYPE_NONE;
 396
 397         /* Enable NAND flash access */
 398         bcma_cc_set32(b47n->cc, BCMA_CC_4706_FLASHSCFG,
 399                       BCMA_CC_4706_FLASHSCFG_NF1);
 400
 401         /* Configure wait counters */
 402         if (b47n->cc->status & BCMA_CC_CHIPST_4706_PKG_OPTION) {
 403                 /* 400 MHz */
 404                 freq = 400000000 / 4;
 405         } else {
 406                 freq = bcma_chipco_pll_read(b47n->cc, 4);
 407                 freq = (freq & 0xFFF) >> 3;
 408                 /* Fixed reference clock 25 MHz and m = 2 */
 409                 freq = (freq * 25000000 / 2) / 4;
 410         }
 411         clock = freq / 1000000;
 412         w0 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(15, clock);
 413         w1 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(20, clock);
 414         w2 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(10, clock);
 415         w3 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(10, clock);
 416         w4 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(100, clock);
 417         bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_WAITCNT0,
 418                         (w4 << 24 | w3 << 18 | w2 << 12 | w1 << 6 | w0));
 419
 420         /* Scan NAND */
 421         err = nand_scan(&b47n->nand_chip, 1);
 422         if (err) {
 423                 pr_err("Could not scan NAND flash: %d\n", err);
 424                 goto exit;
 425         }
 426
 427         /* Configure FLASH */
 428         chipsize = nanddev_target_size(&b47n->nand_chip.base) >> 20;
 429         tbits = ffs(chipsize); /* find first bit set */
 430         if (!tbits || tbits != fls(chipsize)) {
 431                 pr_err("Invalid flash size: 0x%lX\n", chipsize);
 432                 err = -ENOTSUPP;
 433                 goto exit;
 434         }
 435         tbits += 19; /* Broadcom increases *index* by 20, we increase *pos* */
 436
 437         col_bits = b47n->nand_chip.page_shift + 1;
 438         col_size = (col_bits + 7) / 8;
 439
 440         row_bits = tbits - col_bits + 1;
 441         row_bsize = (row_bits + 7) / 8;
 442
 443         val = ((row_bsize - 1) << 6) | ((col_size - 1) << 4) | 2;
 444         bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_CONF, val);
 445
 446 exit:
 447         if (err)
 448                 bcma_cc_mask32(b47n->cc, BCMA_CC_4706_FLASHSCFG,
 449                                ~BCMA_CC_4706_FLASHSCFG_NF1);
 450         return err;
 451 }