1 /* 2 * SMI (Serial Memory Controller) device driver for Serial NOR Flash on 3 * SPEAr platform 4 * The serial nor interface is largely based on m25p80.c, however the SPI 5 * interface has been replaced by SMI. 6 * 7 * Copyright © 2010 STMicroelectronics. 8 * Ashish Priyadarshi 9 * Shiraz Hashim <shiraz.linux.kernel@gmail.com> 10 * 11 * This file is licensed under the terms of the GNU General Public 12 * License version 2. This program is licensed "as is" without any 13 * warranty of any kind, whether express or implied. 14 */ 15 16 #include <linux/clk.h> 17 #include <linux/delay.h> 18 #include <linux/device.h> 19 #include <linux/err.h> 20 #include <linux/errno.h> 21 #include <linux/interrupt.h> 22 #include <linux/io.h> 23 #include <linux/ioport.h> 24 #include <linux/jiffies.h> 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/param.h> 28 #include <linux/platform_device.h> 29 #include <linux/pm.h> 30 #include <linux/mtd/mtd.h> 31 #include <linux/mtd/partitions.h> 32 #include <linux/mtd/spear_smi.h> 33 #include <linux/mutex.h> 34 #include <linux/sched.h> 35 #include <linux/slab.h> 36 #include <linux/wait.h> 37 #include <linux/of.h> 38 #include <linux/of_address.h> 39 40 /* SMI clock rate */ 41 #define SMI_MAX_CLOCK_FREQ 50000000 /* 50 MHz */ 42 43 /* MAX time out to safely come out of a erase or write busy conditions */ 44 #define SMI_PROBE_TIMEOUT (HZ / 10) 45 #define SMI_MAX_TIME_OUT (3 * HZ) 46 47 /* timeout for command completion */ 48 #define SMI_CMD_TIMEOUT (HZ / 10) 49 50 /* registers of smi */ 51 #define SMI_CR1 0x0 /* SMI control register 1 */ 52 #define SMI_CR2 0x4 /* SMI control register 2 */ 53 #define SMI_SR 0x8 /* SMI status register */ 54 #define SMI_TR 0xC /* SMI transmit register */ 55 #define SMI_RR 0x10 /* SMI receive register */ 56 57 /* defines for control_reg 1 */ 58 #define BANK_EN (0xF << 0) /* enables all banks */ 59 #define DSEL_TIME (0x6 << 4) /* Deselect time 6 + 1 SMI_CK periods */ 60 #define SW_MODE (0x1 << 28) /* enables SW Mode */ 61 #define WB_MODE (0x1 << 29) /* Write Burst Mode */ 62 #define FAST_MODE (0x1 << 15) /* Fast Mode */ 63 #define HOLD1 (0x1 << 16) /* Clock Hold period selection */ 64 65 /* defines for control_reg 2 */ 66 #define SEND (0x1 << 7) /* Send data */ 67 #define TFIE (0x1 << 8) /* Transmission Flag Interrupt Enable */ 68 #define WCIE (0x1 << 9) /* Write Complete Interrupt Enable */ 69 #define RD_STATUS_REG (0x1 << 10) /* reads status reg */ 70 #define WE (0x1 << 11) /* Write Enable */ 71 72 #define TX_LEN_SHIFT 0 73 #define RX_LEN_SHIFT 4 74 #define BANK_SHIFT 12 75 76 /* defines for status register */ 77 #define SR_WIP 0x1 /* Write in progress */ 78 #define SR_WEL 0x2 /* Write enable latch */ 79 #define SR_BP0 0x4 /* Block protect 0 */ 80 #define SR_BP1 0x8 /* Block protect 1 */ 81 #define SR_BP2 0x10 /* Block protect 2 */ 82 #define SR_SRWD 0x80 /* SR write protect */ 83 #define TFF 0x100 /* Transfer Finished Flag */ 84 #define WCF 0x200 /* Transfer Finished Flag */ 85 #define ERF1 0x400 /* Forbidden Write Request */ 86 #define ERF2 0x800 /* Forbidden Access */ 87 88 #define WM_SHIFT 12 89 90 /* flash opcodes */ 91 #define OPCODE_RDID 0x9f /* Read JEDEC ID */ 92 93 /* Flash Device Ids maintenance section */ 94 95 /* data structure to maintain flash ids from different vendors */ 96 struct flash_device { 97 char *name; 98 u8 erase_cmd; 99 u32 device_id; 100 u32 pagesize; 101 unsigned long sectorsize; 102 unsigned long size_in_bytes; 103 }; 104 105 #define FLASH_ID(n, es, id, psize, ssize, size) \ 106 { \ 107 .name = n, \ 108 .erase_cmd = es, \ 109 .device_id = id, \ 110 .pagesize = psize, \ 111 .sectorsize = ssize, \ 112 .size_in_bytes = size \ 113 } 114 115 static struct flash_device flash_devices[] = { 116 FLASH_ID("st m25p16" , 0xd8, 0x00152020, 0x100, 0x10000, 0x200000), 117 FLASH_ID("st m25p32" , 0xd8, 0x00162020, 0x100, 0x10000, 0x400000), 118 FLASH_ID("st m25p64" , 0xd8, 0x00172020, 0x100, 0x10000, 0x800000), 119 FLASH_ID("st m25p128" , 0xd8, 0x00182020, 0x100, 0x40000, 0x1000000), 120 FLASH_ID("st m25p05" , 0xd8, 0x00102020, 0x80 , 0x8000 , 0x10000), 121 FLASH_ID("st m25p10" , 0xd8, 0x00112020, 0x80 , 0x8000 , 0x20000), 122 FLASH_ID("st m25p20" , 0xd8, 0x00122020, 0x100, 0x10000, 0x40000), 123 FLASH_ID("st m25p40" , 0xd8, 0x00132020, 0x100, 0x10000, 0x80000), 124 FLASH_ID("st m25p80" , 0xd8, 0x00142020, 0x100, 0x10000, 0x100000), 125 FLASH_ID("st m45pe10" , 0xd8, 0x00114020, 0x100, 0x10000, 0x20000), 126 FLASH_ID("st m45pe20" , 0xd8, 0x00124020, 0x100, 0x10000, 0x40000), 127 FLASH_ID("st m45pe40" , 0xd8, 0x00134020, 0x100, 0x10000, 0x80000), 128 FLASH_ID("st m45pe80" , 0xd8, 0x00144020, 0x100, 0x10000, 0x100000), 129 FLASH_ID("sp s25fl004" , 0xd8, 0x00120201, 0x100, 0x10000, 0x80000), 130 FLASH_ID("sp s25fl008" , 0xd8, 0x00130201, 0x100, 0x10000, 0x100000), 131 FLASH_ID("sp s25fl016" , 0xd8, 0x00140201, 0x100, 0x10000, 0x200000), 132 FLASH_ID("sp s25fl032" , 0xd8, 0x00150201, 0x100, 0x10000, 0x400000), 133 FLASH_ID("sp s25fl064" , 0xd8, 0x00160201, 0x100, 0x10000, 0x800000), 134 FLASH_ID("atmel 25f512" , 0x52, 0x0065001F, 0x80 , 0x8000 , 0x10000), 135 FLASH_ID("atmel 25f1024" , 0x52, 0x0060001F, 0x100, 0x8000 , 0x20000), 136 FLASH_ID("atmel 25f2048" , 0x52, 0x0063001F, 0x100, 0x10000, 0x40000), 137 FLASH_ID("atmel 25f4096" , 0x52, 0x0064001F, 0x100, 0x10000, 0x80000), 138 FLASH_ID("atmel 25fs040" , 0xd7, 0x0004661F, 0x100, 0x10000, 0x80000), 139 FLASH_ID("mac 25l512" , 0xd8, 0x001020C2, 0x010, 0x10000, 0x10000), 140 FLASH_ID("mac 25l1005" , 0xd8, 0x001120C2, 0x010, 0x10000, 0x20000), 141 FLASH_ID("mac 25l2005" , 0xd8, 0x001220C2, 0x010, 0x10000, 0x40000), 142 FLASH_ID("mac 25l4005" , 0xd8, 0x001320C2, 0x010, 0x10000, 0x80000), 143 FLASH_ID("mac 25l4005a" , 0xd8, 0x001320C2, 0x010, 0x10000, 0x80000), 144 FLASH_ID("mac 25l8005" , 0xd8, 0x001420C2, 0x010, 0x10000, 0x100000), 145 FLASH_ID("mac 25l1605" , 0xd8, 0x001520C2, 0x100, 0x10000, 0x200000), 146 FLASH_ID("mac 25l1605a" , 0xd8, 0x001520C2, 0x010, 0x10000, 0x200000), 147 FLASH_ID("mac 25l3205" , 0xd8, 0x001620C2, 0x100, 0x10000, 0x400000), 148 FLASH_ID("mac 25l3205a" , 0xd8, 0x001620C2, 0x100, 0x10000, 0x400000), 149 FLASH_ID("mac 25l6405" , 0xd8, 0x001720C2, 0x100, 0x10000, 0x800000), 150 }; 151 152 /* Define spear specific structures */ 153 154 struct spear_snor_flash; 155 156 /** 157 * struct spear_smi - Structure for SMI Device 158 * 159 * @clk: functional clock 160 * @status: current status register of SMI. 161 * @clk_rate: functional clock rate of SMI (default: SMI_MAX_CLOCK_FREQ) 162 * @lock: lock to prevent parallel access of SMI. 163 * @io_base: base address for registers of SMI. 164 * @pdev: platform device 165 * @cmd_complete: queue to wait for command completion of NOR-flash. 166 * @num_flashes: number of flashes actually present on board. 167 * @flash: separate structure for each Serial NOR-flash attached to SMI. 168 */ 169 struct spear_smi { 170 struct clk *clk; 171 u32 status; 172 unsigned long clk_rate; 173 struct mutex lock; 174 void __iomem *io_base; 175 struct platform_device *pdev; 176 wait_queue_head_t cmd_complete; 177 u32 num_flashes; 178 struct spear_snor_flash *flash[MAX_NUM_FLASH_CHIP]; 179 }; 180 181 /** 182 * struct spear_snor_flash - Structure for Serial NOR Flash 183 * 184 * @bank: Bank number(0, 1, 2, 3) for each NOR-flash. 185 * @dev_id: Device ID of NOR-flash. 186 * @lock: lock to manage flash read, write and erase operations 187 * @mtd: MTD info for each NOR-flash. 188 * @num_parts: Total number of partition in each bank of NOR-flash. 189 * @parts: Partition info for each bank of NOR-flash. 190 * @page_size: Page size of NOR-flash. 191 * @base_addr: Base address of NOR-flash. 192 * @erase_cmd: erase command may vary on different flash types 193 * @fast_mode: flash supports read in fast mode 194 */ 195 struct spear_snor_flash { 196 u32 bank; 197 u32 dev_id; 198 struct mutex lock; 199 struct mtd_info mtd; 200 u32 num_parts; 201 struct mtd_partition *parts; 202 u32 page_size; 203 void __iomem *base_addr; 204 u8 erase_cmd; 205 u8 fast_mode; 206 }; 207 208 static inline struct spear_snor_flash *get_flash_data(struct mtd_info *mtd) 209 { 210 return container_of(mtd, struct spear_snor_flash, mtd); 211 } 212 213 /** 214 * spear_smi_read_sr - Read status register of flash through SMI 215 * @dev: structure of SMI information. 216 * @bank: bank to which flash is connected 217 * 218 * This routine will return the status register of the flash chip present at the 219 * given bank. 220 */ 221 static int spear_smi_read_sr(struct spear_smi *dev, u32 bank) 222 { 223 int ret; 224 u32 ctrlreg1; 225 226 mutex_lock(&dev->lock); 227 dev->status = 0; /* Will be set in interrupt handler */ 228 229 ctrlreg1 = readl(dev->io_base + SMI_CR1); 230 /* program smi in hw mode */ 231 writel(ctrlreg1 & ~(SW_MODE | WB_MODE), dev->io_base + SMI_CR1); 232 233 /* performing a rsr instruction in hw mode */ 234 writel((bank << BANK_SHIFT) | RD_STATUS_REG | TFIE, 235 dev->io_base + SMI_CR2); 236 237 /* wait for tff */ 238 ret = wait_event_interruptible_timeout(dev->cmd_complete, 239 dev->status & TFF, SMI_CMD_TIMEOUT); 240 241 /* copy dev->status (lower 16 bits) in order to release lock */ 242 if (ret > 0) 243 ret = dev->status & 0xffff; 244 else if (ret == 0) 245 ret = -ETIMEDOUT; 246 247 /* restore the ctrl regs state */ 248 writel(ctrlreg1, dev->io_base + SMI_CR1); 249 writel(0, dev->io_base + SMI_CR2); 250 mutex_unlock(&dev->lock); 251 252 return ret; 253 } 254 255 /** 256 * spear_smi_wait_till_ready - wait till flash is ready 257 * @dev: structure of SMI information. 258 * @bank: flash corresponding to this bank 259 * @timeout: timeout for busy wait condition 260 * 261 * This routine checks for WIP (write in progress) bit in Status register 262 * If successful the routine returns 0 else -EBUSY 263 */ 264 static int spear_smi_wait_till_ready(struct spear_smi *dev, u32 bank, 265 unsigned long timeout) 266 { 267 unsigned long finish; 268 int status; 269 270 finish = jiffies + timeout; 271 do { 272 status = spear_smi_read_sr(dev, bank); 273 if (status < 0) { 274 if (status == -ETIMEDOUT) 275 continue; /* try till finish */ 276 return status; 277 } else if (!(status & SR_WIP)) { 278 return 0; 279 } 280 281 cond_resched(); 282 } while (!time_after_eq(jiffies, finish)); 283 284 dev_err(&dev->pdev->dev, "smi controller is busy, timeout\n"); 285 return -EBUSY; 286 } 287 288 /** 289 * spear_smi_int_handler - SMI Interrupt Handler. 290 * @irq: irq number 291 * @dev_id: structure of SMI device, embedded in dev_id. 292 * 293 * The handler clears all interrupt conditions and records the status in 294 * dev->status which is used by the driver later. 295 */ 296 static irqreturn_t spear_smi_int_handler(int irq, void *dev_id) 297 { 298 u32 status = 0; 299 struct spear_smi *dev = dev_id; 300 301 status = readl(dev->io_base + SMI_SR); 302 303 if (unlikely(!status)) 304 return IRQ_NONE; 305 306 /* clear all interrupt conditions */ 307 writel(0, dev->io_base + SMI_SR); 308 309 /* copy the status register in dev->status */ 310 dev->status |= status; 311 312 /* send the completion */ 313 wake_up_interruptible(&dev->cmd_complete); 314 315 return IRQ_HANDLED; 316 } 317 318 /** 319 * spear_smi_hw_init - initializes the smi controller. 320 * @dev: structure of smi device 321 * 322 * this routine initializes the smi controller wit the default values 323 */ 324 static void spear_smi_hw_init(struct spear_smi *dev) 325 { 326 unsigned long rate = 0; 327 u32 prescale = 0; 328 u32 val; 329 330 rate = clk_get_rate(dev->clk); 331 332 /* functional clock of smi */ 333 prescale = DIV_ROUND_UP(rate, dev->clk_rate); 334 335 /* 336 * setting the standard values, fast mode, prescaler for 337 * SMI_MAX_CLOCK_FREQ (50MHz) operation and bank enable 338 */ 339 val = HOLD1 | BANK_EN | DSEL_TIME | (prescale << 8); 340 341 mutex_lock(&dev->lock); 342 /* clear all interrupt conditions */ 343 writel(0, dev->io_base + SMI_SR); 344 345 writel(val, dev->io_base + SMI_CR1); 346 mutex_unlock(&dev->lock); 347 } 348 349 /** 350 * get_flash_index - match chip id from a flash list. 351 * @flash_id: a valid nor flash chip id obtained from board. 352 * 353 * try to validate the chip id by matching from a list, if not found then simply 354 * returns negative. In case of success returns index in to the flash devices 355 * array. 356 */ 357 static int get_flash_index(u32 flash_id) 358 { 359 int index; 360 361 /* Matches chip-id to entire list of 'serial-nor flash' ids */ 362 for (index = 0; index < ARRAY_SIZE(flash_devices); index++) { 363 if (flash_devices[index].device_id == flash_id) 364 return index; 365 } 366 367 /* Memory chip is not listed and not supported */ 368 return -ENODEV; 369 } 370 371 /** 372 * spear_smi_write_enable - Enable the flash to do write operation 373 * @dev: structure of SMI device 374 * @bank: enable write for flash connected to this bank 375 * 376 * Set write enable latch with Write Enable command. 377 * Returns 0 on success. 378 */ 379 static int spear_smi_write_enable(struct spear_smi *dev, u32 bank) 380 { 381 int ret; 382 u32 ctrlreg1; 383 384 mutex_lock(&dev->lock); 385 dev->status = 0; /* Will be set in interrupt handler */ 386 387 ctrlreg1 = readl(dev->io_base + SMI_CR1); 388 /* program smi in h/w mode */ 389 writel(ctrlreg1 & ~SW_MODE, dev->io_base + SMI_CR1); 390 391 /* give the flash, write enable command */ 392 writel((bank << BANK_SHIFT) | WE | TFIE, dev->io_base + SMI_CR2); 393 394 ret = wait_event_interruptible_timeout(dev->cmd_complete, 395 dev->status & TFF, SMI_CMD_TIMEOUT); 396 397 /* restore the ctrl regs state */ 398 writel(ctrlreg1, dev->io_base + SMI_CR1); 399 writel(0, dev->io_base + SMI_CR2); 400 401 if (ret == 0) { 402 ret = -EIO; 403 dev_err(&dev->pdev->dev, 404 "smi controller failed on write enable\n"); 405 } else if (ret > 0) { 406 /* check whether write mode status is set for required bank */ 407 if (dev->status & (1 << (bank + WM_SHIFT))) 408 ret = 0; 409 else { 410 dev_err(&dev->pdev->dev, "couldn't enable write\n"); 411 ret = -EIO; 412 } 413 } 414 415 mutex_unlock(&dev->lock); 416 return ret; 417 } 418 419 static inline u32 420 get_sector_erase_cmd(struct spear_snor_flash *flash, u32 offset) 421 { 422 u32 cmd; 423 u8 *x = (u8 *)&cmd; 424 425 x[0] = flash->erase_cmd; 426 x[1] = offset >> 16; 427 x[2] = offset >> 8; 428 x[3] = offset; 429 430 return cmd; 431 } 432 433 /** 434 * spear_smi_erase_sector - erase one sector of flash 435 * @dev: structure of SMI information 436 * @command: erase command to be send 437 * @bank: bank to which this command needs to be send 438 * @bytes: size of command 439 * 440 * Erase one sector of flash memory at offset ``offset'' which is any 441 * address within the sector which should be erased. 442 * Returns 0 if successful, non-zero otherwise. 443 */ 444 static int spear_smi_erase_sector(struct spear_smi *dev, 445 u32 bank, u32 command, u32 bytes) 446 { 447 u32 ctrlreg1 = 0; 448 int ret; 449 450 ret = spear_smi_wait_till_ready(dev, bank, SMI_MAX_TIME_OUT); 451 if (ret) 452 return ret; 453 454 ret = spear_smi_write_enable(dev, bank); 455 if (ret) 456 return ret; 457 458 mutex_lock(&dev->lock); 459 460 ctrlreg1 = readl(dev->io_base + SMI_CR1); 461 writel((ctrlreg1 | SW_MODE) & ~WB_MODE, dev->io_base + SMI_CR1); 462 463 /* send command in sw mode */ 464 writel(command, dev->io_base + SMI_TR); 465 466 writel((bank << BANK_SHIFT) | SEND | TFIE | (bytes << TX_LEN_SHIFT), 467 dev->io_base + SMI_CR2); 468 469 ret = wait_event_interruptible_timeout(dev->cmd_complete, 470 dev->status & TFF, SMI_CMD_TIMEOUT); 471 472 if (ret == 0) { 473 ret = -EIO; 474 dev_err(&dev->pdev->dev, "sector erase failed\n"); 475 } else if (ret > 0) 476 ret = 0; /* success */ 477 478 /* restore ctrl regs */ 479 writel(ctrlreg1, dev->io_base + SMI_CR1); 480 writel(0, dev->io_base + SMI_CR2); 481 482 mutex_unlock(&dev->lock); 483 return ret; 484 } 485 486 /** 487 * spear_mtd_erase - perform flash erase operation as requested by user 488 * @mtd: Provides the memory characteristics 489 * @e_info: Provides the erase information 490 * 491 * Erase an address range on the flash chip. The address range may extend 492 * one or more erase sectors. Return an error is there is a problem erasing. 493 */ 494 static int spear_mtd_erase(struct mtd_info *mtd, struct erase_info *e_info) 495 { 496 struct spear_snor_flash *flash = get_flash_data(mtd); 497 struct spear_smi *dev = mtd->priv; 498 u32 addr, command, bank; 499 int len, ret; 500 501 if (!flash || !dev) 502 return -ENODEV; 503 504 bank = flash->bank; 505 if (bank > dev->num_flashes - 1) { 506 dev_err(&dev->pdev->dev, "Invalid Bank Num"); 507 return -EINVAL; 508 } 509 510 addr = e_info->addr; 511 len = e_info->len; 512 513 mutex_lock(&flash->lock); 514 515 /* now erase sectors in loop */ 516 while (len) { 517 command = get_sector_erase_cmd(flash, addr); 518 /* preparing the command for flash */ 519 ret = spear_smi_erase_sector(dev, bank, command, 4); 520 if (ret) { 521 mutex_unlock(&flash->lock); 522 return ret; 523 } 524 addr += mtd->erasesize; 525 len -= mtd->erasesize; 526 } 527 528 mutex_unlock(&flash->lock); 529 530 return 0; 531 } 532 533 /** 534 * spear_mtd_read - performs flash read operation as requested by the user 535 * @mtd: MTD information of the memory bank 536 * @from: Address from which to start read 537 * @len: Number of bytes to be read 538 * @retlen: Fills the Number of bytes actually read 539 * @buf: Fills this after reading 540 * 541 * Read an address range from the flash chip. The address range 542 * may be any size provided it is within the physical boundaries. 543 * Returns 0 on success, non zero otherwise 544 */ 545 static int spear_mtd_read(struct mtd_info *mtd, loff_t from, size_t len, 546 size_t *retlen, u8 *buf) 547 { 548 struct spear_snor_flash *flash = get_flash_data(mtd); 549 struct spear_smi *dev = mtd->priv; 550 void __iomem *src; 551 u32 ctrlreg1, val; 552 int ret; 553 554 if (!flash || !dev) 555 return -ENODEV; 556 557 if (flash->bank > dev->num_flashes - 1) { 558 dev_err(&dev->pdev->dev, "Invalid Bank Num"); 559 return -EINVAL; 560 } 561 562 /* select address as per bank number */ 563 src = flash->base_addr + from; 564 565 mutex_lock(&flash->lock); 566 567 /* wait till previous write/erase is done. */ 568 ret = spear_smi_wait_till_ready(dev, flash->bank, SMI_MAX_TIME_OUT); 569 if (ret) { 570 mutex_unlock(&flash->lock); 571 return ret; 572 } 573 574 mutex_lock(&dev->lock); 575 /* put smi in hw mode not wbt mode */ 576 ctrlreg1 = val = readl(dev->io_base + SMI_CR1); 577 val &= ~(SW_MODE | WB_MODE); 578 if (flash->fast_mode) 579 val |= FAST_MODE; 580 581 writel(val, dev->io_base + SMI_CR1); 582 583 memcpy_fromio(buf, src, len); 584 585 /* restore ctrl reg1 */ 586 writel(ctrlreg1, dev->io_base + SMI_CR1); 587 mutex_unlock(&dev->lock); 588 589 *retlen = len; 590 mutex_unlock(&flash->lock); 591 592 return 0; 593 } 594 595 /* 596 * The purpose of this function is to ensure a memcpy_toio() with byte writes 597 * only. Its structure is inspired from the ARM implementation of _memcpy_toio() 598 * which also does single byte writes but cannot be used here as this is just an 599 * implementation detail and not part of the API. Not mentioning the comment 600 * stating that _memcpy_toio() should be optimized. 601 */ 602 static void spear_smi_memcpy_toio_b(volatile void __iomem *dest, 603 const void *src, size_t len) 604 { 605 const unsigned char *from = src; 606 607 while (len) { 608 len--; 609 writeb(*from, dest); 610 from++; 611 dest++; 612 } 613 } 614 615 static inline int spear_smi_cpy_toio(struct spear_smi *dev, u32 bank, 616 void __iomem *dest, const void *src, size_t len) 617 { 618 int ret; 619 u32 ctrlreg1; 620 621 /* wait until finished previous write command. */ 622 ret = spear_smi_wait_till_ready(dev, bank, SMI_MAX_TIME_OUT); 623 if (ret) 624 return ret; 625 626 /* put smi in write enable */ 627 ret = spear_smi_write_enable(dev, bank); 628 if (ret) 629 return ret; 630 631 /* put smi in hw, write burst mode */ 632 mutex_lock(&dev->lock); 633 634 ctrlreg1 = readl(dev->io_base + SMI_CR1); 635 writel((ctrlreg1 | WB_MODE) & ~SW_MODE, dev->io_base + SMI_CR1); 636 637 /* 638 * In Write Burst mode (WB_MODE), the specs states that writes must be: 639 * - incremental 640 * - of the same size 641 * The ARM implementation of memcpy_toio() will optimize the number of 642 * I/O by using as much 4-byte writes as possible, surrounded by 643 * 2-byte/1-byte access if: 644 * - the destination is not 4-byte aligned 645 * - the length is not a multiple of 4-byte. 646 * Avoid this alternance of write access size by using our own 'byte 647 * access' helper if at least one of the two conditions above is true. 648 */ 649 if (IS_ALIGNED(len, sizeof(u32)) && 650 IS_ALIGNED((uintptr_t)dest, sizeof(u32))) 651 memcpy_toio(dest, src, len); 652 else 653 spear_smi_memcpy_toio_b(dest, src, len); 654 655 writel(ctrlreg1, dev->io_base + SMI_CR1); 656 657 mutex_unlock(&dev->lock); 658 return 0; 659 } 660 661 /** 662 * spear_mtd_write - performs write operation as requested by the user. 663 * @mtd: MTD information of the memory bank. 664 * @to: Address to write. 665 * @len: Number of bytes to be written. 666 * @retlen: Number of bytes actually wrote. 667 * @buf: Buffer from which the data to be taken. 668 * 669 * Write an address range to the flash chip. Data must be written in 670 * flash_page_size chunks. The address range may be any size provided 671 * it is within the physical boundaries. 672 * Returns 0 on success, non zero otherwise 673 */ 674 static int spear_mtd_write(struct mtd_info *mtd, loff_t to, size_t len, 675 size_t *retlen, const u8 *buf) 676 { 677 struct spear_snor_flash *flash = get_flash_data(mtd); 678 struct spear_smi *dev = mtd->priv; 679 void __iomem *dest; 680 u32 page_offset, page_size; 681 int ret; 682 683 if (!flash || !dev) 684 return -ENODEV; 685 686 if (flash->bank > dev->num_flashes - 1) { 687 dev_err(&dev->pdev->dev, "Invalid Bank Num"); 688 return -EINVAL; 689 } 690 691 /* select address as per bank number */ 692 dest = flash->base_addr + to; 693 mutex_lock(&flash->lock); 694 695 page_offset = (u32)to % flash->page_size; 696 697 /* do if all the bytes fit onto one page */ 698 if (page_offset + len <= flash->page_size) { 699 ret = spear_smi_cpy_toio(dev, flash->bank, dest, buf, len); 700 if (!ret) 701 *retlen += len; 702 } else { 703 u32 i; 704 705 /* the size of data remaining on the first page */ 706 page_size = flash->page_size - page_offset; 707 708 ret = spear_smi_cpy_toio(dev, flash->bank, dest, buf, 709 page_size); 710 if (ret) 711 goto err_write; 712 else 713 *retlen += page_size; 714 715 /* write everything in pagesize chunks */ 716 for (i = page_size; i < len; i += page_size) { 717 page_size = len - i; 718 if (page_size > flash->page_size) 719 page_size = flash->page_size; 720 721 ret = spear_smi_cpy_toio(dev, flash->bank, dest + i, 722 buf + i, page_size); 723 if (ret) 724 break; 725 else 726 *retlen += page_size; 727 } 728 } 729 730 err_write: 731 mutex_unlock(&flash->lock); 732 733 return ret; 734 } 735 736 /** 737 * spear_smi_probe_flash - Detects the NOR Flash chip. 738 * @dev: structure of SMI information. 739 * @bank: bank on which flash must be probed 740 * 741 * This routine will check whether there exists a flash chip on a given memory 742 * bank ID. 743 * Return index of the probed flash in flash devices structure 744 */ 745 static int spear_smi_probe_flash(struct spear_smi *dev, u32 bank) 746 { 747 int ret; 748 u32 val = 0; 749 750 ret = spear_smi_wait_till_ready(dev, bank, SMI_PROBE_TIMEOUT); 751 if (ret) 752 return ret; 753 754 mutex_lock(&dev->lock); 755 756 dev->status = 0; /* Will be set in interrupt handler */ 757 /* put smi in sw mode */ 758 val = readl(dev->io_base + SMI_CR1); 759 writel(val | SW_MODE, dev->io_base + SMI_CR1); 760 761 /* send readid command in sw mode */ 762 writel(OPCODE_RDID, dev->io_base + SMI_TR); 763 764 val = (bank << BANK_SHIFT) | SEND | (1 << TX_LEN_SHIFT) | 765 (3 << RX_LEN_SHIFT) | TFIE; 766 writel(val, dev->io_base + SMI_CR2); 767 768 /* wait for TFF */ 769 ret = wait_event_interruptible_timeout(dev->cmd_complete, 770 dev->status & TFF, SMI_CMD_TIMEOUT); 771 if (ret <= 0) { 772 ret = -ENODEV; 773 goto err_probe; 774 } 775 776 /* get memory chip id */ 777 val = readl(dev->io_base + SMI_RR); 778 val &= 0x00ffffff; 779 ret = get_flash_index(val); 780 781 err_probe: 782 /* clear sw mode */ 783 val = readl(dev->io_base + SMI_CR1); 784 writel(val & ~SW_MODE, dev->io_base + SMI_CR1); 785 786 mutex_unlock(&dev->lock); 787 return ret; 788 } 789 790 791 #ifdef CONFIG_OF 792 static int spear_smi_probe_config_dt(struct platform_device *pdev, 793 struct device_node *np) 794 { 795 struct spear_smi_plat_data *pdata = dev_get_platdata(&pdev->dev); 796 struct device_node *pp = NULL; 797 const __be32 *addr; 798 u32 val; 799 int len; 800 int i = 0; 801 802 if (!np) 803 return -ENODEV; 804 805 of_property_read_u32(np, "clock-rate", &val); 806 pdata->clk_rate = val; 807 808 pdata->board_flash_info = devm_kzalloc(&pdev->dev, 809 sizeof(*pdata->board_flash_info), 810 GFP_KERNEL); 811 if (!pdata->board_flash_info) 812 return -ENOMEM; 813 814 /* Fill structs for each subnode (flash device) */ 815 while ((pp = of_get_next_child(np, pp))) { 816 pdata->np[i] = pp; 817 818 /* Read base-addr and size from DT */ 819 addr = of_get_property(pp, "reg", &len); 820 pdata->board_flash_info->mem_base = be32_to_cpup(&addr[0]); 821 pdata->board_flash_info->size = be32_to_cpup(&addr[1]); 822 823 if (of_get_property(pp, "st,smi-fast-mode", NULL)) 824 pdata->board_flash_info->fast_mode = 1; 825 826 i++; 827 } 828 829 pdata->num_flashes = i; 830 831 return 0; 832 } 833 #else 834 static int spear_smi_probe_config_dt(struct platform_device *pdev, 835 struct device_node *np) 836 { 837 return -ENOSYS; 838 } 839 #endif 840 841 static int spear_smi_setup_banks(struct platform_device *pdev, 842 u32 bank, struct device_node *np) 843 { 844 struct spear_smi *dev = platform_get_drvdata(pdev); 845 struct spear_smi_flash_info *flash_info; 846 struct spear_smi_plat_data *pdata; 847 struct spear_snor_flash *flash; 848 struct mtd_partition *parts = NULL; 849 int count = 0; 850 int flash_index; 851 int ret = 0; 852 853 pdata = dev_get_platdata(&pdev->dev); 854 if (bank > pdata->num_flashes - 1) 855 return -EINVAL; 856 857 flash_info = &pdata->board_flash_info[bank]; 858 if (!flash_info) 859 return -ENODEV; 860 861 flash = devm_kzalloc(&pdev->dev, sizeof(*flash), GFP_ATOMIC); 862 if (!flash) 863 return -ENOMEM; 864 flash->bank = bank; 865 flash->fast_mode = flash_info->fast_mode ? 1 : 0; 866 mutex_init(&flash->lock); 867 868 /* verify whether nor flash is really present on board */ 869 flash_index = spear_smi_probe_flash(dev, bank); 870 if (flash_index < 0) { 871 dev_info(&dev->pdev->dev, "smi-nor%d not found\n", bank); 872 return flash_index; 873 } 874 /* map the memory for nor flash chip */ 875 flash->base_addr = devm_ioremap(&pdev->dev, flash_info->mem_base, 876 flash_info->size); 877 if (!flash->base_addr) 878 return -EIO; 879 880 dev->flash[bank] = flash; 881 flash->mtd.priv = dev; 882 883 if (flash_info->name) 884 flash->mtd.name = flash_info->name; 885 else 886 flash->mtd.name = flash_devices[flash_index].name; 887 888 flash->mtd.dev.parent = &pdev->dev; 889 mtd_set_of_node(&flash->mtd, np); 890 flash->mtd.type = MTD_NORFLASH; 891 flash->mtd.writesize = 1; 892 flash->mtd.flags = MTD_CAP_NORFLASH; 893 flash->mtd.size = flash_info->size; 894 flash->mtd.erasesize = flash_devices[flash_index].sectorsize; 895 flash->page_size = flash_devices[flash_index].pagesize; 896 flash->mtd.writebufsize = flash->page_size; 897 flash->erase_cmd = flash_devices[flash_index].erase_cmd; 898 flash->mtd._erase = spear_mtd_erase; 899 flash->mtd._read = spear_mtd_read; 900 flash->mtd._write = spear_mtd_write; 901 flash->dev_id = flash_devices[flash_index].device_id; 902 903 dev_info(&dev->pdev->dev, "mtd .name=%s .size=%llx(%lluM)\n", 904 flash->mtd.name, flash->mtd.size, 905 flash->mtd.size / (1024 * 1024)); 906 907 dev_info(&dev->pdev->dev, ".erasesize = 0x%x(%uK)\n", 908 flash->mtd.erasesize, flash->mtd.erasesize / 1024); 909 910 #ifndef CONFIG_OF 911 if (flash_info->partitions) { 912 parts = flash_info->partitions; 913 count = flash_info->nr_partitions; 914 } 915 #endif 916 917 ret = mtd_device_register(&flash->mtd, parts, count); 918 if (ret) { 919 dev_err(&dev->pdev->dev, "Err MTD partition=%d\n", ret); 920 return ret; 921 } 922 923 return 0; 924 } 925 926 /** 927 * spear_smi_probe - Entry routine 928 * @pdev: platform device structure 929 * 930 * This is the first routine which gets invoked during booting and does all 931 * initialization/allocation work. The routine looks for available memory banks, 932 * and do proper init for any found one. 933 * Returns 0 on success, non zero otherwise 934 */ 935 static int spear_smi_probe(struct platform_device *pdev) 936 { 937 struct device_node *np = pdev->dev.of_node; 938 struct spear_smi_plat_data *pdata = NULL; 939 struct spear_smi *dev; 940 struct resource *smi_base; 941 int irq, ret = 0; 942 int i; 943 944 if (np) { 945 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); 946 if (!pdata) { 947 ret = -ENOMEM; 948 goto err; 949 } 950 pdev->dev.platform_data = pdata; 951 ret = spear_smi_probe_config_dt(pdev, np); 952 if (ret) { 953 ret = -ENODEV; 954 dev_err(&pdev->dev, "no platform data\n"); 955 goto err; 956 } 957 } else { 958 pdata = dev_get_platdata(&pdev->dev); 959 if (!pdata) { 960 ret = -ENODEV; 961 dev_err(&pdev->dev, "no platform data\n"); 962 goto err; 963 } 964 } 965 966 irq = platform_get_irq(pdev, 0); 967 if (irq < 0) { 968 ret = -ENODEV; 969 goto err; 970 } 971 972 dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_ATOMIC); 973 if (!dev) { 974 ret = -ENOMEM; 975 goto err; 976 } 977 978 smi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); 979 980 dev->io_base = devm_ioremap_resource(&pdev->dev, smi_base); 981 if (IS_ERR(dev->io_base)) { 982 ret = PTR_ERR(dev->io_base); 983 goto err; 984 } 985 986 dev->pdev = pdev; 987 dev->clk_rate = pdata->clk_rate; 988 989 if (dev->clk_rate > SMI_MAX_CLOCK_FREQ) 990 dev->clk_rate = SMI_MAX_CLOCK_FREQ; 991 992 dev->num_flashes = pdata->num_flashes; 993 994 if (dev->num_flashes > MAX_NUM_FLASH_CHIP) { 995 dev_err(&pdev->dev, "exceeding max number of flashes\n"); 996 dev->num_flashes = MAX_NUM_FLASH_CHIP; 997 } 998 999 dev->clk = devm_clk_get(&pdev->dev, NULL); 1000 if (IS_ERR(dev->clk)) { 1001 ret = PTR_ERR(dev->clk); 1002 goto err; 1003 } 1004 1005 ret = clk_prepare_enable(dev->clk); 1006 if (ret) 1007 goto err; 1008 1009 ret = devm_request_irq(&pdev->dev, irq, spear_smi_int_handler, 0, 1010 pdev->name, dev); 1011 if (ret) { 1012 dev_err(&dev->pdev->dev, "SMI IRQ allocation failed\n"); 1013 goto err_irq; 1014 } 1015 1016 mutex_init(&dev->lock); 1017 init_waitqueue_head(&dev->cmd_complete); 1018 spear_smi_hw_init(dev); 1019 platform_set_drvdata(pdev, dev); 1020 1021 /* loop for each serial nor-flash which is connected to smi */ 1022 for (i = 0; i < dev->num_flashes; i++) { 1023 ret = spear_smi_setup_banks(pdev, i, pdata->np[i]); 1024 if (ret) { 1025 dev_err(&dev->pdev->dev, "bank setup failed\n"); 1026 goto err_irq; 1027 } 1028 } 1029 1030 return 0; 1031 1032 err_irq: 1033 clk_disable_unprepare(dev->clk); 1034 err: 1035 return ret; 1036 } 1037 1038 /** 1039 * spear_smi_remove - Exit routine 1040 * @pdev: platform device structure 1041 * 1042 * free all allocations and delete the partitions. 1043 */ 1044 static int spear_smi_remove(struct platform_device *pdev) 1045 { 1046 struct spear_smi *dev; 1047 struct spear_snor_flash *flash; 1048 int ret, i; 1049 1050 dev = platform_get_drvdata(pdev); 1051 if (!dev) { 1052 dev_err(&pdev->dev, "dev is null\n"); 1053 return -ENODEV; 1054 } 1055 1056 /* clean up for all nor flash */ 1057 for (i = 0; i < dev->num_flashes; i++) { 1058 flash = dev->flash[i]; 1059 if (!flash) 1060 continue; 1061 1062 /* clean up mtd stuff */ 1063 ret = mtd_device_unregister(&flash->mtd); 1064 if (ret) 1065 dev_err(&pdev->dev, "error removing mtd\n"); 1066 } 1067 1068 clk_disable_unprepare(dev->clk); 1069 1070 return 0; 1071 } 1072 1073 #ifdef CONFIG_PM_SLEEP 1074 static int spear_smi_suspend(struct device *dev) 1075 { 1076 struct spear_smi *sdev = dev_get_drvdata(dev); 1077 1078 if (sdev && sdev->clk) 1079 clk_disable_unprepare(sdev->clk); 1080 1081 return 0; 1082 } 1083 1084 static int spear_smi_resume(struct device *dev) 1085 { 1086 struct spear_smi *sdev = dev_get_drvdata(dev); 1087 int ret = -EPERM; 1088 1089 if (sdev && sdev->clk) 1090 ret = clk_prepare_enable(sdev->clk); 1091 1092 if (!ret) 1093 spear_smi_hw_init(sdev); 1094 return ret; 1095 } 1096 #endif 1097 1098 static SIMPLE_DEV_PM_OPS(spear_smi_pm_ops, spear_smi_suspend, spear_smi_resume); 1099 1100 #ifdef CONFIG_OF 1101 static const struct of_device_id spear_smi_id_table[] = { 1102 { .compatible = "st,spear600-smi" }, 1103 {} 1104 }; 1105 MODULE_DEVICE_TABLE(of, spear_smi_id_table); 1106 #endif 1107 1108 static struct platform_driver spear_smi_driver = { 1109 .driver = { 1110 .name = "smi", 1111 .bus = &platform_bus_type, 1112 .of_match_table = of_match_ptr(spear_smi_id_table), 1113 .pm = &spear_smi_pm_ops, 1114 }, 1115 .probe = spear_smi_probe, 1116 .remove = spear_smi_remove, 1117 }; 1118 module_platform_driver(spear_smi_driver); 1119 1120 MODULE_LICENSE("GPL"); 1121 MODULE_AUTHOR("Ashish Priyadarshi, Shiraz Hashim <shiraz.linux.kernel@gmail.com>"); 1122 MODULE_DESCRIPTION("MTD SMI driver for serial nor flash chips"); 1123