1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * LPDDR2-NVM MTD driver. This module provides read, write, erase, lock/unlock 4 * support for LPDDR2-NVM PCM memories 5 * 6 * Copyright © 2012 Micron Technology, Inc. 7 * 8 * Vincenzo Aliberti <vincenzo.aliberti@gmail.com> 9 * Domenico Manna <domenico.manna@gmail.com> 10 * Many thanks to Andrea Vigilante for initial enabling 11 */ 12 13 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__ 14 15 #include <linux/init.h> 16 #include <linux/io.h> 17 #include <linux/module.h> 18 #include <linux/kernel.h> 19 #include <linux/mtd/map.h> 20 #include <linux/mtd/mtd.h> 21 #include <linux/mtd/partitions.h> 22 #include <linux/slab.h> 23 #include <linux/platform_device.h> 24 #include <linux/ioport.h> 25 #include <linux/err.h> 26 27 /* Parameters */ 28 #define ERASE_BLOCKSIZE (0x00020000/2) /* in Word */ 29 #define WRITE_BUFFSIZE (0x00000400/2) /* in Word */ 30 #define OW_BASE_ADDRESS 0x00000000 /* OW offset */ 31 #define BUS_WIDTH 0x00000020 /* x32 devices */ 32 33 /* PFOW symbols address offset */ 34 #define PFOW_QUERY_STRING_P (0x0000/2) /* in Word */ 35 #define PFOW_QUERY_STRING_F (0x0002/2) /* in Word */ 36 #define PFOW_QUERY_STRING_O (0x0004/2) /* in Word */ 37 #define PFOW_QUERY_STRING_W (0x0006/2) /* in Word */ 38 39 /* OW registers address */ 40 #define CMD_CODE_OFS (0x0080/2) /* in Word */ 41 #define CMD_DATA_OFS (0x0084/2) /* in Word */ 42 #define CMD_ADD_L_OFS (0x0088/2) /* in Word */ 43 #define CMD_ADD_H_OFS (0x008A/2) /* in Word */ 44 #define MPR_L_OFS (0x0090/2) /* in Word */ 45 #define MPR_H_OFS (0x0092/2) /* in Word */ 46 #define CMD_EXEC_OFS (0x00C0/2) /* in Word */ 47 #define STATUS_REG_OFS (0x00CC/2) /* in Word */ 48 #define PRG_BUFFER_OFS (0x0010/2) /* in Word */ 49 50 /* Datamask */ 51 #define MR_CFGMASK 0x8000 52 #define SR_OK_DATAMASK 0x0080 53 54 /* LPDDR2-NVM Commands */ 55 #define LPDDR2_NVM_LOCK 0x0061 56 #define LPDDR2_NVM_UNLOCK 0x0062 57 #define LPDDR2_NVM_SW_PROGRAM 0x0041 58 #define LPDDR2_NVM_SW_OVERWRITE 0x0042 59 #define LPDDR2_NVM_BUF_PROGRAM 0x00E9 60 #define LPDDR2_NVM_BUF_OVERWRITE 0x00EA 61 #define LPDDR2_NVM_ERASE 0x0020 62 63 /* LPDDR2-NVM Registers offset */ 64 #define LPDDR2_MODE_REG_DATA 0x0040 65 #define LPDDR2_MODE_REG_CFG 0x0050 66 67 /* 68 * Internal Type Definitions 69 * pcm_int_data contains memory controller details: 70 * @reg_data : LPDDR2_MODE_REG_DATA register address after remapping 71 * @reg_cfg : LPDDR2_MODE_REG_CFG register address after remapping 72 * &bus_width: memory bus-width (eg: x16 2 Bytes, x32 4 Bytes) 73 */ 74 struct pcm_int_data { 75 void __iomem *ctl_regs; 76 int bus_width; 77 }; 78 79 static DEFINE_MUTEX(lpdd2_nvm_mutex); 80 81 /* 82 * Build a map_word starting from an u_long 83 */ 84 static inline map_word build_map_word(u_long myword) 85 { 86 map_word val = { {0} }; 87 val.x[0] = myword; 88 return val; 89 } 90 91 /* 92 * Build Mode Register Configuration DataMask based on device bus-width 93 */ 94 static inline u_int build_mr_cfgmask(u_int bus_width) 95 { 96 u_int val = MR_CFGMASK; 97 98 if (bus_width == 0x0004) /* x32 device */ 99 val = val << 16; 100 101 return val; 102 } 103 104 /* 105 * Build Status Register OK DataMask based on device bus-width 106 */ 107 static inline u_int build_sr_ok_datamask(u_int bus_width) 108 { 109 u_int val = SR_OK_DATAMASK; 110 111 if (bus_width == 0x0004) /* x32 device */ 112 val = (val << 16)+val; 113 114 return val; 115 } 116 117 /* 118 * Evaluates Overlay Window Control Registers address 119 */ 120 static inline u_long ow_reg_add(struct map_info *map, u_long offset) 121 { 122 u_long val = 0; 123 struct pcm_int_data *pcm_data = map->fldrv_priv; 124 125 val = map->pfow_base + offset*pcm_data->bus_width; 126 127 return val; 128 } 129 130 /* 131 * Enable lpddr2-nvm Overlay Window 132 * Overlay Window is a memory mapped area containing all LPDDR2-NVM registers 133 * used by device commands as well as uservisible resources like Device Status 134 * Register, Device ID, etc 135 */ 136 static inline void ow_enable(struct map_info *map) 137 { 138 struct pcm_int_data *pcm_data = map->fldrv_priv; 139 140 writel_relaxed(build_mr_cfgmask(pcm_data->bus_width) | 0x18, 141 pcm_data->ctl_regs + LPDDR2_MODE_REG_CFG); 142 writel_relaxed(0x01, pcm_data->ctl_regs + LPDDR2_MODE_REG_DATA); 143 } 144 145 /* 146 * Disable lpddr2-nvm Overlay Window 147 * Overlay Window is a memory mapped area containing all LPDDR2-NVM registers 148 * used by device commands as well as uservisible resources like Device Status 149 * Register, Device ID, etc 150 */ 151 static inline void ow_disable(struct map_info *map) 152 { 153 struct pcm_int_data *pcm_data = map->fldrv_priv; 154 155 writel_relaxed(build_mr_cfgmask(pcm_data->bus_width) | 0x18, 156 pcm_data->ctl_regs + LPDDR2_MODE_REG_CFG); 157 writel_relaxed(0x02, pcm_data->ctl_regs + LPDDR2_MODE_REG_DATA); 158 } 159 160 /* 161 * Execute lpddr2-nvm operations 162 */ 163 static int lpddr2_nvm_do_op(struct map_info *map, u_long cmd_code, 164 u_long cmd_data, u_long cmd_add, u_long cmd_mpr, u_char *buf) 165 { 166 map_word add_l = { {0} }, add_h = { {0} }, mpr_l = { {0} }, 167 mpr_h = { {0} }, data_l = { {0} }, cmd = { {0} }, 168 exec_cmd = { {0} }, sr; 169 map_word data_h = { {0} }; /* only for 2x x16 devices stacked */ 170 u_long i, status_reg, prg_buff_ofs; 171 struct pcm_int_data *pcm_data = map->fldrv_priv; 172 u_int sr_ok_datamask = build_sr_ok_datamask(pcm_data->bus_width); 173 174 /* Builds low and high words for OW Control Registers */ 175 add_l.x[0] = cmd_add & 0x0000FFFF; 176 add_h.x[0] = (cmd_add >> 16) & 0x0000FFFF; 177 mpr_l.x[0] = cmd_mpr & 0x0000FFFF; 178 mpr_h.x[0] = (cmd_mpr >> 16) & 0x0000FFFF; 179 cmd.x[0] = cmd_code & 0x0000FFFF; 180 exec_cmd.x[0] = 0x0001; 181 data_l.x[0] = cmd_data & 0x0000FFFF; 182 data_h.x[0] = (cmd_data >> 16) & 0x0000FFFF; /* only for 2x x16 */ 183 184 /* Set Overlay Window Control Registers */ 185 map_write(map, cmd, ow_reg_add(map, CMD_CODE_OFS)); 186 map_write(map, data_l, ow_reg_add(map, CMD_DATA_OFS)); 187 map_write(map, add_l, ow_reg_add(map, CMD_ADD_L_OFS)); 188 map_write(map, add_h, ow_reg_add(map, CMD_ADD_H_OFS)); 189 map_write(map, mpr_l, ow_reg_add(map, MPR_L_OFS)); 190 map_write(map, mpr_h, ow_reg_add(map, MPR_H_OFS)); 191 if (pcm_data->bus_width == 0x0004) { /* 2x16 devices stacked */ 192 map_write(map, cmd, ow_reg_add(map, CMD_CODE_OFS) + 2); 193 map_write(map, data_h, ow_reg_add(map, CMD_DATA_OFS) + 2); 194 map_write(map, add_l, ow_reg_add(map, CMD_ADD_L_OFS) + 2); 195 map_write(map, add_h, ow_reg_add(map, CMD_ADD_H_OFS) + 2); 196 map_write(map, mpr_l, ow_reg_add(map, MPR_L_OFS) + 2); 197 map_write(map, mpr_h, ow_reg_add(map, MPR_H_OFS) + 2); 198 } 199 200 /* Fill Program Buffer */ 201 if ((cmd_code == LPDDR2_NVM_BUF_PROGRAM) || 202 (cmd_code == LPDDR2_NVM_BUF_OVERWRITE)) { 203 prg_buff_ofs = (map_read(map, 204 ow_reg_add(map, PRG_BUFFER_OFS))).x[0]; 205 for (i = 0; i < cmd_mpr; i++) { 206 map_write(map, build_map_word(buf[i]), map->pfow_base + 207 prg_buff_ofs + i); 208 } 209 } 210 211 /* Command Execute */ 212 map_write(map, exec_cmd, ow_reg_add(map, CMD_EXEC_OFS)); 213 if (pcm_data->bus_width == 0x0004) /* 2x16 devices stacked */ 214 map_write(map, exec_cmd, ow_reg_add(map, CMD_EXEC_OFS) + 2); 215 216 /* Status Register Check */ 217 do { 218 sr = map_read(map, ow_reg_add(map, STATUS_REG_OFS)); 219 status_reg = sr.x[0]; 220 if (pcm_data->bus_width == 0x0004) {/* 2x16 devices stacked */ 221 sr = map_read(map, ow_reg_add(map, 222 STATUS_REG_OFS) + 2); 223 status_reg += sr.x[0] << 16; 224 } 225 } while ((status_reg & sr_ok_datamask) != sr_ok_datamask); 226 227 return (((status_reg & sr_ok_datamask) == sr_ok_datamask) ? 0 : -EIO); 228 } 229 230 /* 231 * Execute lpddr2-nvm operations @ block level 232 */ 233 static int lpddr2_nvm_do_block_op(struct mtd_info *mtd, loff_t start_add, 234 uint64_t len, u_char block_op) 235 { 236 struct map_info *map = mtd->priv; 237 u_long add, end_add; 238 int ret = 0; 239 240 mutex_lock(&lpdd2_nvm_mutex); 241 242 ow_enable(map); 243 244 add = start_add; 245 end_add = add + len; 246 247 do { 248 ret = lpddr2_nvm_do_op(map, block_op, 0x00, add, add, NULL); 249 if (ret) 250 goto out; 251 add += mtd->erasesize; 252 } while (add < end_add); 253 254 out: 255 ow_disable(map); 256 mutex_unlock(&lpdd2_nvm_mutex); 257 return ret; 258 } 259 260 /* 261 * verify presence of PFOW string 262 */ 263 static int lpddr2_nvm_pfow_present(struct map_info *map) 264 { 265 map_word pfow_val[4]; 266 unsigned int found = 1; 267 268 mutex_lock(&lpdd2_nvm_mutex); 269 270 ow_enable(map); 271 272 /* Load string from array */ 273 pfow_val[0] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_P)); 274 pfow_val[1] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_F)); 275 pfow_val[2] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_O)); 276 pfow_val[3] = map_read(map, ow_reg_add(map, PFOW_QUERY_STRING_W)); 277 278 /* Verify the string loaded vs expected */ 279 if (!map_word_equal(map, build_map_word('P'), pfow_val[0])) 280 found = 0; 281 if (!map_word_equal(map, build_map_word('F'), pfow_val[1])) 282 found = 0; 283 if (!map_word_equal(map, build_map_word('O'), pfow_val[2])) 284 found = 0; 285 if (!map_word_equal(map, build_map_word('W'), pfow_val[3])) 286 found = 0; 287 288 ow_disable(map); 289 290 mutex_unlock(&lpdd2_nvm_mutex); 291 292 return found; 293 } 294 295 /* 296 * lpddr2_nvm driver read method 297 */ 298 static int lpddr2_nvm_read(struct mtd_info *mtd, loff_t start_add, 299 size_t len, size_t *retlen, u_char *buf) 300 { 301 struct map_info *map = mtd->priv; 302 303 mutex_lock(&lpdd2_nvm_mutex); 304 305 *retlen = len; 306 307 map_copy_from(map, buf, start_add, *retlen); 308 309 mutex_unlock(&lpdd2_nvm_mutex); 310 return 0; 311 } 312 313 /* 314 * lpddr2_nvm driver write method 315 */ 316 static int lpddr2_nvm_write(struct mtd_info *mtd, loff_t start_add, 317 size_t len, size_t *retlen, const u_char *buf) 318 { 319 struct map_info *map = mtd->priv; 320 struct pcm_int_data *pcm_data = map->fldrv_priv; 321 u_long add, current_len, tot_len, target_len, my_data; 322 u_char *write_buf = (u_char *)buf; 323 int ret = 0; 324 325 mutex_lock(&lpdd2_nvm_mutex); 326 327 ow_enable(map); 328 329 /* Set start value for the variables */ 330 add = start_add; 331 target_len = len; 332 tot_len = 0; 333 334 while (tot_len < target_len) { 335 if (!(IS_ALIGNED(add, mtd->writesize))) { /* do sw program */ 336 my_data = write_buf[tot_len]; 337 my_data += (write_buf[tot_len+1]) << 8; 338 if (pcm_data->bus_width == 0x0004) {/* 2x16 devices */ 339 my_data += (write_buf[tot_len+2]) << 16; 340 my_data += (write_buf[tot_len+3]) << 24; 341 } 342 ret = lpddr2_nvm_do_op(map, LPDDR2_NVM_SW_OVERWRITE, 343 my_data, add, 0x00, NULL); 344 if (ret) 345 goto out; 346 347 add += pcm_data->bus_width; 348 tot_len += pcm_data->bus_width; 349 } else { /* do buffer program */ 350 current_len = min(target_len - tot_len, 351 (u_long) mtd->writesize); 352 ret = lpddr2_nvm_do_op(map, LPDDR2_NVM_BUF_OVERWRITE, 353 0x00, add, current_len, write_buf + tot_len); 354 if (ret) 355 goto out; 356 357 add += current_len; 358 tot_len += current_len; 359 } 360 } 361 362 out: 363 *retlen = tot_len; 364 ow_disable(map); 365 mutex_unlock(&lpdd2_nvm_mutex); 366 return ret; 367 } 368 369 /* 370 * lpddr2_nvm driver erase method 371 */ 372 static int lpddr2_nvm_erase(struct mtd_info *mtd, struct erase_info *instr) 373 { 374 return lpddr2_nvm_do_block_op(mtd, instr->addr, instr->len, 375 LPDDR2_NVM_ERASE); 376 } 377 378 /* 379 * lpddr2_nvm driver unlock method 380 */ 381 static int lpddr2_nvm_unlock(struct mtd_info *mtd, loff_t start_add, 382 uint64_t len) 383 { 384 return lpddr2_nvm_do_block_op(mtd, start_add, len, LPDDR2_NVM_UNLOCK); 385 } 386 387 /* 388 * lpddr2_nvm driver lock method 389 */ 390 static int lpddr2_nvm_lock(struct mtd_info *mtd, loff_t start_add, 391 uint64_t len) 392 { 393 return lpddr2_nvm_do_block_op(mtd, start_add, len, LPDDR2_NVM_LOCK); 394 } 395 396 static const struct mtd_info lpddr2_nvm_mtd_info = { 397 .type = MTD_RAM, 398 .writesize = 1, 399 .flags = (MTD_CAP_NVRAM | MTD_POWERUP_LOCK), 400 ._read = lpddr2_nvm_read, 401 ._write = lpddr2_nvm_write, 402 ._erase = lpddr2_nvm_erase, 403 ._unlock = lpddr2_nvm_unlock, 404 ._lock = lpddr2_nvm_lock, 405 }; 406 407 /* 408 * lpddr2_nvm driver probe method 409 */ 410 static int lpddr2_nvm_probe(struct platform_device *pdev) 411 { 412 struct map_info *map; 413 struct mtd_info *mtd; 414 struct resource *add_range; 415 struct pcm_int_data *pcm_data; 416 417 /* Allocate memory control_regs data structures */ 418 pcm_data = devm_kzalloc(&pdev->dev, sizeof(*pcm_data), GFP_KERNEL); 419 if (!pcm_data) 420 return -ENOMEM; 421 422 pcm_data->bus_width = BUS_WIDTH; 423 424 /* Allocate memory for map_info & mtd_info data structures */ 425 map = devm_kzalloc(&pdev->dev, sizeof(*map), GFP_KERNEL); 426 if (!map) 427 return -ENOMEM; 428 429 mtd = devm_kzalloc(&pdev->dev, sizeof(*mtd), GFP_KERNEL); 430 if (!mtd) 431 return -ENOMEM; 432 433 /* lpddr2_nvm address range */ 434 add_range = platform_get_resource(pdev, IORESOURCE_MEM, 0); 435 if (!add_range) 436 return -ENODEV; 437 438 /* Populate map_info data structure */ 439 *map = (struct map_info) { 440 .virt = devm_ioremap_resource(&pdev->dev, add_range), 441 .name = pdev->dev.init_name, 442 .phys = add_range->start, 443 .size = resource_size(add_range), 444 .bankwidth = pcm_data->bus_width / 2, 445 .pfow_base = OW_BASE_ADDRESS, 446 .fldrv_priv = pcm_data, 447 }; 448 449 if (IS_ERR(map->virt)) 450 return PTR_ERR(map->virt); 451 452 simple_map_init(map); /* fill with default methods */ 453 454 pcm_data->ctl_regs = devm_platform_ioremap_resource(pdev, 1); 455 if (IS_ERR(pcm_data->ctl_regs)) 456 return PTR_ERR(pcm_data->ctl_regs); 457 458 /* Populate mtd_info data structure */ 459 *mtd = lpddr2_nvm_mtd_info; 460 mtd->dev.parent = &pdev->dev; 461 mtd->name = pdev->dev.init_name; 462 mtd->priv = map; 463 mtd->size = resource_size(add_range); 464 mtd->erasesize = ERASE_BLOCKSIZE * pcm_data->bus_width; 465 mtd->writebufsize = WRITE_BUFFSIZE * pcm_data->bus_width; 466 467 /* Verify the presence of the device looking for PFOW string */ 468 if (!lpddr2_nvm_pfow_present(map)) { 469 pr_err("device not recognized\n"); 470 return -EINVAL; 471 } 472 /* Parse partitions and register the MTD device */ 473 return mtd_device_register(mtd, NULL, 0); 474 } 475 476 /* 477 * lpddr2_nvm driver remove method 478 */ 479 static void lpddr2_nvm_remove(struct platform_device *pdev) 480 { 481 WARN_ON(mtd_device_unregister(dev_get_drvdata(&pdev->dev))); 482 } 483 484 /* Initialize platform_driver data structure for lpddr2_nvm */ 485 static struct platform_driver lpddr2_nvm_drv = { 486 .driver = { 487 .name = "lpddr2_nvm", 488 }, 489 .probe = lpddr2_nvm_probe, 490 .remove_new = lpddr2_nvm_remove, 491 }; 492 493 module_platform_driver(lpddr2_nvm_drv); 494 MODULE_LICENSE("GPL"); 495 MODULE_AUTHOR("Vincenzo Aliberti <vincenzo.aliberti@gmail.com>"); 496 MODULE_DESCRIPTION("MTD driver for LPDDR2-NVM PCM memories"); 497