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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Based on m25p80.c, by Mike Lavender (mike@steroidmicros.com), with
   4 * influence from lart.c (Abraham Van Der Merwe) and mtd_dataflash.c
   5 *
   6 * Copyright (C) 2005, Intec Automation Inc.
   7 * Copyright (C) 2014, Freescale Semiconductor, Inc.
   8 */
   9
  10#include <linux/err.h>
  11#include <linux/errno.h>
  12#include <linux/delay.h>
  13#include <linux/device.h>
  14#include <linux/math64.h>
  15#include <linux/module.h>
  16#include <linux/mtd/mtd.h>
  17#include <linux/mtd/spi-nor.h>
  18#include <linux/mutex.h>
  19#include <linux/of_platform.h>
  20#include <linux/sched/task_stack.h>
  21#include <linux/sizes.h>
  22#include <linux/slab.h>
  23#include <linux/spi/flash.h>
  24
  25#include "core.h"
  26
  27/* Define max times to check status register before we give up. */
  28
  29/*
  30 * For everything but full-chip erase; probably could be much smaller, but kept
  31 * around for safety for now
  32 */
  33#define DEFAULT_READY_WAIT_JIFFIES		(40UL * HZ)
  34
  35/*
  36 * For full-chip erase, calibrated to a 2MB flash (M25P16); should be scaled up
  37 * for larger flash
  38 */
  39#define CHIP_ERASE_2MB_READY_WAIT_JIFFIES	(40UL * HZ)
  40
  41#define SPI_NOR_MAX_ADDR_NBYTES	4
  42
  43#define SPI_NOR_SRST_SLEEP_MIN 200
  44#define SPI_NOR_SRST_SLEEP_MAX 400
  45
  46/**
  47 * spi_nor_get_cmd_ext() - Get the command opcode extension based on the
  48 *			   extension type.
  49 * @nor:		pointer to a 'struct spi_nor'
  50 * @op:			pointer to the 'struct spi_mem_op' whose properties
  51 *			need to be initialized.
  52 *
  53 * Right now, only "repeat" and "invert" are supported.
  54 *
  55 * Return: The opcode extension.
  56 */
  57static u8 spi_nor_get_cmd_ext(const struct spi_nor *nor,
  58			      const struct spi_mem_op *op)
  59{
  60	switch (nor->cmd_ext_type) {
  61	case SPI_NOR_EXT_INVERT:
  62		return ~op->cmd.opcode;
  63
  64	case SPI_NOR_EXT_REPEAT:
  65		return op->cmd.opcode;
  66
  67	default:
  68		dev_err(nor->dev, "Unknown command extension type\n");
  69		return 0;
  70	}
  71}
  72
  73/**
  74 * spi_nor_spimem_setup_op() - Set up common properties of a spi-mem op.
  75 * @nor:		pointer to a 'struct spi_nor'
  76 * @op:			pointer to the 'struct spi_mem_op' whose properties
  77 *			need to be initialized.
  78 * @proto:		the protocol from which the properties need to be set.
  79 */
  80void spi_nor_spimem_setup_op(const struct spi_nor *nor,
  81			     struct spi_mem_op *op,
  82			     const enum spi_nor_protocol proto)
  83{
  84	u8 ext;
  85
  86	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(proto);
  87
  88	if (op->addr.nbytes)
  89		op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
  90
  91	if (op->dummy.nbytes)
  92		op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
  93
  94	if (op->data.nbytes)
  95		op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
  96
  97	if (spi_nor_protocol_is_dtr(proto)) {
  98		/*
  99		 * SPIMEM supports mixed DTR modes, but right now we can only
 100		 * have all phases either DTR or STR. IOW, SPIMEM can have
 101		 * something like 4S-4D-4D, but SPI NOR can't. So, set all 4
 102		 * phases to either DTR or STR.
 103		 */
 104		op->cmd.dtr = true;
 105		op->addr.dtr = true;
 106		op->dummy.dtr = true;
 107		op->data.dtr = true;
 108
 109		/* 2 bytes per clock cycle in DTR mode. */
 110		op->dummy.nbytes *= 2;
 111
 112		ext = spi_nor_get_cmd_ext(nor, op);
 113		op->cmd.opcode = (op->cmd.opcode << 8) | ext;
 114		op->cmd.nbytes = 2;
 115	}
 116}
 117
 118/**
 119 * spi_nor_spimem_bounce() - check if a bounce buffer is needed for the data
 120 *                           transfer
 121 * @nor:        pointer to 'struct spi_nor'
 122 * @op:         pointer to 'struct spi_mem_op' template for transfer
 123 *
 124 * If we have to use the bounce buffer, the data field in @op will be updated.
 125 *
 126 * Return: true if the bounce buffer is needed, false if not
 127 */
 128static bool spi_nor_spimem_bounce(struct spi_nor *nor, struct spi_mem_op *op)
 129{
 130	/* op->data.buf.in occupies the same memory as op->data.buf.out */
 131	if (object_is_on_stack(op->data.buf.in) ||
 132	    !virt_addr_valid(op->data.buf.in)) {
 133		if (op->data.nbytes > nor->bouncebuf_size)
 134			op->data.nbytes = nor->bouncebuf_size;
 135		op->data.buf.in = nor->bouncebuf;
 136		return true;
 137	}
 138
 139	return false;
 140}
 141
 142/**
 143 * spi_nor_spimem_exec_op() - execute a memory operation
 144 * @nor:        pointer to 'struct spi_nor'
 145 * @op:         pointer to 'struct spi_mem_op' template for transfer
 146 *
 147 * Return: 0 on success, -error otherwise.
 148 */
 149static int spi_nor_spimem_exec_op(struct spi_nor *nor, struct spi_mem_op *op)
 150{
 151	int error;
 152
 153	error = spi_mem_adjust_op_size(nor->spimem, op);
 154	if (error)
 155		return error;
 156
 157	return spi_mem_exec_op(nor->spimem, op);
 158}
 159
 160int spi_nor_controller_ops_read_reg(struct spi_nor *nor, u8 opcode,
 161				    u8 *buf, size_t len)
 162{
 163	if (spi_nor_protocol_is_dtr(nor->reg_proto))
 164		return -EOPNOTSUPP;
 165
 166	return nor->controller_ops->read_reg(nor, opcode, buf, len);
 167}
 168
 169int spi_nor_controller_ops_write_reg(struct spi_nor *nor, u8 opcode,
 170				     const u8 *buf, size_t len)
 171{
 172	if (spi_nor_protocol_is_dtr(nor->reg_proto))
 173		return -EOPNOTSUPP;
 174
 175	return nor->controller_ops->write_reg(nor, opcode, buf, len);
 176}
 177
 178static int spi_nor_controller_ops_erase(struct spi_nor *nor, loff_t offs)
 179{
 180	if (spi_nor_protocol_is_dtr(nor->reg_proto))
 181		return -EOPNOTSUPP;
 182
 183	return nor->controller_ops->erase(nor, offs);
 184}
 185
 186/**
 187 * spi_nor_spimem_read_data() - read data from flash's memory region via
 188 *                              spi-mem
 189 * @nor:        pointer to 'struct spi_nor'
 190 * @from:       offset to read from
 191 * @len:        number of bytes to read
 192 * @buf:        pointer to dst buffer
 193 *
 194 * Return: number of bytes read successfully, -errno otherwise
 195 */
 196static ssize_t spi_nor_spimem_read_data(struct spi_nor *nor, loff_t from,
 197					size_t len, u8 *buf)
 198{
 199	struct spi_mem_op op =
 200		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
 201			   SPI_MEM_OP_ADDR(nor->addr_nbytes, from, 0),
 202			   SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
 203			   SPI_MEM_OP_DATA_IN(len, buf, 0));
 204	bool usebouncebuf;
 205	ssize_t nbytes;
 206	int error;
 207
 208	spi_nor_spimem_setup_op(nor, &op, nor->read_proto);
 209
 210	/* convert the dummy cycles to the number of bytes */
 211	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
 212	if (spi_nor_protocol_is_dtr(nor->read_proto))
 213		op.dummy.nbytes *= 2;
 214
 215	usebouncebuf = spi_nor_spimem_bounce(nor, &op);
 216
 217	if (nor->dirmap.rdesc) {
 218		nbytes = spi_mem_dirmap_read(nor->dirmap.rdesc, op.addr.val,
 219					     op.data.nbytes, op.data.buf.in);
 220	} else {
 221		error = spi_nor_spimem_exec_op(nor, &op);
 222		if (error)
 223			return error;
 224		nbytes = op.data.nbytes;
 225	}
 226
 227	if (usebouncebuf && nbytes > 0)
 228		memcpy(buf, op.data.buf.in, nbytes);
 229
 230	return nbytes;
 231}
 232
 233/**
 234 * spi_nor_read_data() - read data from flash memory
 235 * @nor:        pointer to 'struct spi_nor'
 236 * @from:       offset to read from
 237 * @len:        number of bytes to read
 238 * @buf:        pointer to dst buffer
 239 *
 240 * Return: number of bytes read successfully, -errno otherwise
 241 */
 242ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len, u8 *buf)
 243{
 244	if (nor->spimem)
 245		return spi_nor_spimem_read_data(nor, from, len, buf);
 246
 247	return nor->controller_ops->read(nor, from, len, buf);
 248}
 249
 250/**
 251 * spi_nor_spimem_write_data() - write data to flash memory via
 252 *                               spi-mem
 253 * @nor:        pointer to 'struct spi_nor'
 254 * @to:         offset to write to
 255 * @len:        number of bytes to write
 256 * @buf:        pointer to src buffer
 257 *
 258 * Return: number of bytes written successfully, -errno otherwise
 259 */
 260static ssize_t spi_nor_spimem_write_data(struct spi_nor *nor, loff_t to,
 261					 size_t len, const u8 *buf)
 262{
 263	struct spi_mem_op op =
 264		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
 265			   SPI_MEM_OP_ADDR(nor->addr_nbytes, to, 0),
 266			   SPI_MEM_OP_NO_DUMMY,
 267			   SPI_MEM_OP_DATA_OUT(len, buf, 0));
 268	ssize_t nbytes;
 269	int error;
 270
 271	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
 272		op.addr.nbytes = 0;
 273
 274	spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
 275
 276	if (spi_nor_spimem_bounce(nor, &op))
 277		memcpy(nor->bouncebuf, buf, op.data.nbytes);
 278
 279	if (nor->dirmap.wdesc) {
 280		nbytes = spi_mem_dirmap_write(nor->dirmap.wdesc, op.addr.val,
 281					      op.data.nbytes, op.data.buf.out);
 282	} else {
 283		error = spi_nor_spimem_exec_op(nor, &op);
 284		if (error)
 285			return error;
 286		nbytes = op.data.nbytes;
 287	}
 288
 289	return nbytes;
 290}
 291
 292/**
 293 * spi_nor_write_data() - write data to flash memory
 294 * @nor:        pointer to 'struct spi_nor'
 295 * @to:         offset to write to
 296 * @len:        number of bytes to write
 297 * @buf:        pointer to src buffer
 298 *
 299 * Return: number of bytes written successfully, -errno otherwise
 300 */
 301ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
 302			   const u8 *buf)
 303{
 304	if (nor->spimem)
 305		return spi_nor_spimem_write_data(nor, to, len, buf);
 306
 307	return nor->controller_ops->write(nor, to, len, buf);
 308}
 309
 310/**
 311 * spi_nor_read_any_reg() - read any register from flash memory, nonvolatile or
 312 * volatile.
 313 * @nor:        pointer to 'struct spi_nor'.
 314 * @op:		SPI memory operation. op->data.buf must be DMA-able.
 315 * @proto:	SPI protocol to use for the register operation.
 316 *
 317 * Return: zero on success, -errno otherwise
 318 */
 319int spi_nor_read_any_reg(struct spi_nor *nor, struct spi_mem_op *op,
 320			 enum spi_nor_protocol proto)
 321{
 322	if (!nor->spimem)
 323		return -EOPNOTSUPP;
 324
 325	spi_nor_spimem_setup_op(nor, op, proto);
 326	return spi_nor_spimem_exec_op(nor, op);
 327}
 328
 329/**
 330 * spi_nor_write_any_volatile_reg() - write any volatile register to flash
 331 * memory.
 332 * @nor:        pointer to 'struct spi_nor'
 333 * @op:		SPI memory operation. op->data.buf must be DMA-able.
 334 * @proto:	SPI protocol to use for the register operation.
 335 *
 336 * Writing volatile registers are instant according to some manufacturers
 337 * (Cypress, Micron) and do not need any status polling.
 338 *
 339 * Return: zero on success, -errno otherwise
 340 */
 341int spi_nor_write_any_volatile_reg(struct spi_nor *nor, struct spi_mem_op *op,
 342				   enum spi_nor_protocol proto)
 343{
 344	int ret;
 345
 346	if (!nor->spimem)
 347		return -EOPNOTSUPP;
 348
 349	ret = spi_nor_write_enable(nor);
 350	if (ret)
 351		return ret;
 352	spi_nor_spimem_setup_op(nor, op, proto);
 353	return spi_nor_spimem_exec_op(nor, op);
 354}
 355
 356/**
 357 * spi_nor_write_enable() - Set write enable latch with Write Enable command.
 358 * @nor:	pointer to 'struct spi_nor'.
 359 *
 360 * Return: 0 on success, -errno otherwise.
 361 */
 362int spi_nor_write_enable(struct spi_nor *nor)
 363{
 364	int ret;
 365
 366	if (nor->spimem) {
 367		struct spi_mem_op op = SPI_NOR_WREN_OP;
 368
 369		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 370
 371		ret = spi_mem_exec_op(nor->spimem, &op);
 372	} else {
 373		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WREN,
 374						       NULL, 0);
 375	}
 376
 377	if (ret)
 378		dev_dbg(nor->dev, "error %d on Write Enable\n", ret);
 379
 380	return ret;
 381}
 382
 383/**
 384 * spi_nor_write_disable() - Send Write Disable instruction to the chip.
 385 * @nor:	pointer to 'struct spi_nor'.
 386 *
 387 * Return: 0 on success, -errno otherwise.
 388 */
 389int spi_nor_write_disable(struct spi_nor *nor)
 390{
 391	int ret;
 392
 393	if (nor->spimem) {
 394		struct spi_mem_op op = SPI_NOR_WRDI_OP;
 395
 396		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 397
 398		ret = spi_mem_exec_op(nor->spimem, &op);
 399	} else {
 400		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRDI,
 401						       NULL, 0);
 402	}
 403
 404	if (ret)
 405		dev_dbg(nor->dev, "error %d on Write Disable\n", ret);
 406
 407	return ret;
 408}
 409
 410/**
 411 * spi_nor_read_id() - Read the JEDEC ID.
 412 * @nor:	pointer to 'struct spi_nor'.
 413 * @naddr:	number of address bytes to send. Can be zero if the operation
 414 *		does not need to send an address.
 415 * @ndummy:	number of dummy bytes to send after an opcode or address. Can
 416 *		be zero if the operation does not require dummy bytes.
 417 * @id:		pointer to a DMA-able buffer where the value of the JEDEC ID
 418 *		will be written.
 419 * @proto:	the SPI protocol for register operation.
 420 *
 421 * Return: 0 on success, -errno otherwise.
 422 */
 423int spi_nor_read_id(struct spi_nor *nor, u8 naddr, u8 ndummy, u8 *id,
 424		    enum spi_nor_protocol proto)
 425{
 426	int ret;
 427
 428	if (nor->spimem) {
 429		struct spi_mem_op op =
 430			SPI_NOR_READID_OP(naddr, ndummy, id, SPI_NOR_MAX_ID_LEN);
 431
 432		spi_nor_spimem_setup_op(nor, &op, proto);
 433		ret = spi_mem_exec_op(nor->spimem, &op);
 434	} else {
 435		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDID, id,
 436						    SPI_NOR_MAX_ID_LEN);
 437	}
 438	return ret;
 439}
 440
 441/**
 442 * spi_nor_read_sr() - Read the Status Register.
 443 * @nor:	pointer to 'struct spi_nor'.
 444 * @sr:		pointer to a DMA-able buffer where the value of the
 445 *              Status Register will be written. Should be at least 2 bytes.
 446 *
 447 * Return: 0 on success, -errno otherwise.
 448 */
 449int spi_nor_read_sr(struct spi_nor *nor, u8 *sr)
 450{
 451	int ret;
 452
 453	if (nor->spimem) {
 454		struct spi_mem_op op = SPI_NOR_RDSR_OP(sr);
 455
 456		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
 457			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
 458			op.dummy.nbytes = nor->params->rdsr_dummy;
 459			/*
 460			 * We don't want to read only one byte in DTR mode. So,
 461			 * read 2 and then discard the second byte.
 462			 */
 463			op.data.nbytes = 2;
 464		}
 465
 466		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 467
 468		ret = spi_mem_exec_op(nor->spimem, &op);
 469	} else {
 470		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR, sr,
 471						      1);
 472	}
 473
 474	if (ret)
 475		dev_dbg(nor->dev, "error %d reading SR\n", ret);
 476
 477	return ret;
 478}
 479
 480/**
 481 * spi_nor_read_cr() - Read the Configuration Register using the
 482 * SPINOR_OP_RDCR (35h) command.
 483 * @nor:	pointer to 'struct spi_nor'
 484 * @cr:		pointer to a DMA-able buffer where the value of the
 485 *              Configuration Register will be written.
 486 *
 487 * Return: 0 on success, -errno otherwise.
 488 */
 489int spi_nor_read_cr(struct spi_nor *nor, u8 *cr)
 490{
 491	int ret;
 492
 493	if (nor->spimem) {
 494		struct spi_mem_op op = SPI_NOR_RDCR_OP(cr);
 495
 496		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 497
 498		ret = spi_mem_exec_op(nor->spimem, &op);
 499	} else {
 500		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDCR, cr,
 501						      1);
 502	}
 503
 504	if (ret)
 505		dev_dbg(nor->dev, "error %d reading CR\n", ret);
 506
 507	return ret;
 508}
 509
 510/**
 511 * spi_nor_set_4byte_addr_mode_en4b_ex4b() - Enter/Exit 4-byte address mode
 512 *			using SPINOR_OP_EN4B/SPINOR_OP_EX4B. Typically used by
 513 *			Winbond and Macronix.
 514 * @nor:	pointer to 'struct spi_nor'.
 515 * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
 516 *		address mode.
 517 *
 518 * Return: 0 on success, -errno otherwise.
 519 */
 520int spi_nor_set_4byte_addr_mode_en4b_ex4b(struct spi_nor *nor, bool enable)
 521{
 522	int ret;
 523
 524	if (nor->spimem) {
 525		struct spi_mem_op op = SPI_NOR_EN4B_EX4B_OP(enable);
 526
 527		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 528
 529		ret = spi_mem_exec_op(nor->spimem, &op);
 530	} else {
 531		ret = spi_nor_controller_ops_write_reg(nor,
 532						       enable ? SPINOR_OP_EN4B :
 533								SPINOR_OP_EX4B,
 534						       NULL, 0);
 535	}
 536
 537	if (ret)
 538		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
 539
 540	return ret;
 541}
 542
 543/**
 544 * spi_nor_set_4byte_addr_mode_wren_en4b_ex4b() - Set 4-byte address mode using
 545 * SPINOR_OP_WREN followed by SPINOR_OP_EN4B or SPINOR_OP_EX4B. Typically used
 546 * by ST and Micron flashes.
 547 * @nor:	pointer to 'struct spi_nor'.
 548 * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
 549 *		address mode.
 550 *
 551 * Return: 0 on success, -errno otherwise.
 552 */
 553int spi_nor_set_4byte_addr_mode_wren_en4b_ex4b(struct spi_nor *nor, bool enable)
 554{
 555	int ret;
 556
 557	ret = spi_nor_write_enable(nor);
 558	if (ret)
 559		return ret;
 560
 561	ret = spi_nor_set_4byte_addr_mode_en4b_ex4b(nor, enable);
 562	if (ret)
 563		return ret;
 564
 565	return spi_nor_write_disable(nor);
 566}
 567
 568/**
 569 * spi_nor_set_4byte_addr_mode_brwr() - Set 4-byte address mode using
 570 *			SPINOR_OP_BRWR. Typically used by Spansion flashes.
 571 * @nor:	pointer to 'struct spi_nor'.
 572 * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
 573 *		address mode.
 574 *
 575 * 8-bit volatile bank register used to define A[30:A24] bits. MSB (bit[7]) is
 576 * used to enable/disable 4-byte address mode. When MSB is set to ‘1’, 4-byte
 577 * address mode is active and A[30:24] bits are don’t care. Write instruction is
 578 * SPINOR_OP_BRWR(17h) with 1 byte of data.
 579 *
 580 * Return: 0 on success, -errno otherwise.
 581 */
 582int spi_nor_set_4byte_addr_mode_brwr(struct spi_nor *nor, bool enable)
 583{
 584	int ret;
 585
 586	nor->bouncebuf[0] = enable << 7;
 587
 588	if (nor->spimem) {
 589		struct spi_mem_op op = SPI_NOR_BRWR_OP(nor->bouncebuf);
 590
 591		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 592
 593		ret = spi_mem_exec_op(nor->spimem, &op);
 594	} else {
 595		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_BRWR,
 596						       nor->bouncebuf, 1);
 597	}
 598
 599	if (ret)
 600		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
 601
 602	return ret;
 603}
 604
 605/**
 606 * spi_nor_sr_ready() - Query the Status Register to see if the flash is ready
 607 * for new commands.
 608 * @nor:	pointer to 'struct spi_nor'.
 609 *
 610 * Return: 1 if ready, 0 if not ready, -errno on errors.
 611 */
 612int spi_nor_sr_ready(struct spi_nor *nor)
 613{
 614	int ret;
 615
 616	ret = spi_nor_read_sr(nor, nor->bouncebuf);
 617	if (ret)
 618		return ret;
 619
 620	return !(nor->bouncebuf[0] & SR_WIP);
 621}
 622
 623/**
 624 * spi_nor_use_parallel_locking() - Checks if RWW locking scheme shall be used
 625 * @nor:	pointer to 'struct spi_nor'.
 626 *
 627 * Return: true if parallel locking is enabled, false otherwise.
 628 */
 629static bool spi_nor_use_parallel_locking(struct spi_nor *nor)
 630{
 631	return nor->flags & SNOR_F_RWW;
 632}
 633
 634/* Locking helpers for status read operations */
 635static int spi_nor_rww_start_rdst(struct spi_nor *nor)
 636{
 637	struct spi_nor_rww *rww = &nor->rww;
 638	int ret = -EAGAIN;
 639
 640	mutex_lock(&nor->lock);
 641
 642	if (rww->ongoing_io || rww->ongoing_rd)
 643		goto busy;
 644
 645	rww->ongoing_io = true;
 646	rww->ongoing_rd = true;
 647	ret = 0;
 648
 649busy:
 650	mutex_unlock(&nor->lock);
 651	return ret;
 652}
 653
 654static void spi_nor_rww_end_rdst(struct spi_nor *nor)
 655{
 656	struct spi_nor_rww *rww = &nor->rww;
 657
 658	mutex_lock(&nor->lock);
 659
 660	rww->ongoing_io = false;
 661	rww->ongoing_rd = false;
 662
 663	mutex_unlock(&nor->lock);
 664}
 665
 666static int spi_nor_lock_rdst(struct spi_nor *nor)
 667{
 668	if (spi_nor_use_parallel_locking(nor))
 669		return spi_nor_rww_start_rdst(nor);
 670
 671	return 0;
 672}
 673
 674static void spi_nor_unlock_rdst(struct spi_nor *nor)
 675{
 676	if (spi_nor_use_parallel_locking(nor)) {
 677		spi_nor_rww_end_rdst(nor);
 678		wake_up(&nor->rww.wait);
 679	}
 680}
 681
 682/**
 683 * spi_nor_ready() - Query the flash to see if it is ready for new commands.
 684 * @nor:	pointer to 'struct spi_nor'.
 685 *
 686 * Return: 1 if ready, 0 if not ready, -errno on errors.
 687 */
 688static int spi_nor_ready(struct spi_nor *nor)
 689{
 690	int ret;
 691
 692	ret = spi_nor_lock_rdst(nor);
 693	if (ret)
 694		return 0;
 695
 696	/* Flashes might override the standard routine. */
 697	if (nor->params->ready)
 698		ret = nor->params->ready(nor);
 699	else
 700		ret = spi_nor_sr_ready(nor);
 701
 702	spi_nor_unlock_rdst(nor);
 703
 704	return ret;
 705}
 706
 707/**
 708 * spi_nor_wait_till_ready_with_timeout() - Service routine to read the
 709 * Status Register until ready, or timeout occurs.
 710 * @nor:		pointer to "struct spi_nor".
 711 * @timeout_jiffies:	jiffies to wait until timeout.
 712 *
 713 * Return: 0 on success, -errno otherwise.
 714 */
 715static int spi_nor_wait_till_ready_with_timeout(struct spi_nor *nor,
 716						unsigned long timeout_jiffies)
 717{
 718	unsigned long deadline;
 719	int timeout = 0, ret;
 720
 721	deadline = jiffies + timeout_jiffies;
 722
 723	while (!timeout) {
 724		if (time_after_eq(jiffies, deadline))
 725			timeout = 1;
 726
 727		ret = spi_nor_ready(nor);
 728		if (ret < 0)
 729			return ret;
 730		if (ret)
 731			return 0;
 732
 733		cond_resched();
 734	}
 735
 736	dev_dbg(nor->dev, "flash operation timed out\n");
 737
 738	return -ETIMEDOUT;
 739}
 740
 741/**
 742 * spi_nor_wait_till_ready() - Wait for a predefined amount of time for the
 743 * flash to be ready, or timeout occurs.
 744 * @nor:	pointer to "struct spi_nor".
 745 *
 746 * Return: 0 on success, -errno otherwise.
 747 */
 748int spi_nor_wait_till_ready(struct spi_nor *nor)
 749{
 750	return spi_nor_wait_till_ready_with_timeout(nor,
 751						    DEFAULT_READY_WAIT_JIFFIES);
 752}
 753
 754/**
 755 * spi_nor_global_block_unlock() - Unlock Global Block Protection.
 756 * @nor:	pointer to 'struct spi_nor'.
 757 *
 758 * Return: 0 on success, -errno otherwise.
 759 */
 760int spi_nor_global_block_unlock(struct spi_nor *nor)
 761{
 762	int ret;
 763
 764	ret = spi_nor_write_enable(nor);
 765	if (ret)
 766		return ret;
 767
 768	if (nor->spimem) {
 769		struct spi_mem_op op = SPI_NOR_GBULK_OP;
 770
 771		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 772
 773		ret = spi_mem_exec_op(nor->spimem, &op);
 774	} else {
 775		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_GBULK,
 776						       NULL, 0);
 777	}
 778
 779	if (ret) {
 780		dev_dbg(nor->dev, "error %d on Global Block Unlock\n", ret);
 781		return ret;
 782	}
 783
 784	return spi_nor_wait_till_ready(nor);
 785}
 786
 787/**
 788 * spi_nor_write_sr() - Write the Status Register.
 789 * @nor:	pointer to 'struct spi_nor'.
 790 * @sr:		pointer to DMA-able buffer to write to the Status Register.
 791 * @len:	number of bytes to write to the Status Register.
 792 *
 793 * Return: 0 on success, -errno otherwise.
 794 */
 795int spi_nor_write_sr(struct spi_nor *nor, const u8 *sr, size_t len)
 796{
 797	int ret;
 798
 799	ret = spi_nor_write_enable(nor);
 800	if (ret)
 801		return ret;
 802
 803	if (nor->spimem) {
 804		struct spi_mem_op op = SPI_NOR_WRSR_OP(sr, len);
 805
 806		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 807
 808		ret = spi_mem_exec_op(nor->spimem, &op);
 809	} else {
 810		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR, sr,
 811						       len);
 812	}
 813
 814	if (ret) {
 815		dev_dbg(nor->dev, "error %d writing SR\n", ret);
 816		return ret;
 817	}
 818
 819	return spi_nor_wait_till_ready(nor);
 820}
 821
 822/**
 823 * spi_nor_write_sr1_and_check() - Write one byte to the Status Register 1 and
 824 * ensure that the byte written match the received value.
 825 * @nor:	pointer to a 'struct spi_nor'.
 826 * @sr1:	byte value to be written to the Status Register.
 827 *
 828 * Return: 0 on success, -errno otherwise.
 829 */
 830static int spi_nor_write_sr1_and_check(struct spi_nor *nor, u8 sr1)
 831{
 832	int ret;
 833
 834	nor->bouncebuf[0] = sr1;
 835
 836	ret = spi_nor_write_sr(nor, nor->bouncebuf, 1);
 837	if (ret)
 838		return ret;
 839
 840	ret = spi_nor_read_sr(nor, nor->bouncebuf);
 841	if (ret)
 842		return ret;
 843
 844	if (nor->bouncebuf[0] != sr1) {
 845		dev_dbg(nor->dev, "SR1: read back test failed\n");
 846		return -EIO;
 847	}
 848
 849	return 0;
 850}
 851
 852/**
 853 * spi_nor_write_16bit_sr_and_check() - Write the Status Register 1 and the
 854 * Status Register 2 in one shot. Ensure that the byte written in the Status
 855 * Register 1 match the received value, and that the 16-bit Write did not
 856 * affect what was already in the Status Register 2.
 857 * @nor:	pointer to a 'struct spi_nor'.
 858 * @sr1:	byte value to be written to the Status Register 1.
 859 *
 860 * Return: 0 on success, -errno otherwise.
 861 */
 862static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1)
 863{
 864	int ret;
 865	u8 *sr_cr = nor->bouncebuf;
 866	u8 cr_written;
 867
 868	/* Make sure we don't overwrite the contents of Status Register 2. */
 869	if (!(nor->flags & SNOR_F_NO_READ_CR)) {
 870		ret = spi_nor_read_cr(nor, &sr_cr[1]);
 871		if (ret)
 872			return ret;
 873	} else if (spi_nor_get_protocol_width(nor->read_proto) == 4 &&
 874		   spi_nor_get_protocol_width(nor->write_proto) == 4 &&
 875		   nor->params->quad_enable) {
 876		/*
 877		 * If the Status Register 2 Read command (35h) is not
 878		 * supported, we should at least be sure we don't
 879		 * change the value of the SR2 Quad Enable bit.
 880		 *
 881		 * When the Quad Enable method is set and the buswidth is 4, we
 882		 * can safely assume that the value of the QE bit is one, as a
 883		 * consequence of the nor->params->quad_enable() call.
 884		 *
 885		 * According to the JESD216 revB standard, BFPT DWORDS[15],
 886		 * bits 22:20, the 16-bit Write Status (01h) command is
 887		 * available just for the cases in which the QE bit is
 888		 * described in SR2 at BIT(1).
 889		 */
 890		sr_cr[1] = SR2_QUAD_EN_BIT1;
 891	} else {
 892		sr_cr[1] = 0;
 893	}
 894
 895	sr_cr[0] = sr1;
 896
 897	ret = spi_nor_write_sr(nor, sr_cr, 2);
 898	if (ret)
 899		return ret;
 900
 901	ret = spi_nor_read_sr(nor, sr_cr);
 902	if (ret)
 903		return ret;
 904
 905	if (sr1 != sr_cr[0]) {
 906		dev_dbg(nor->dev, "SR: Read back test failed\n");
 907		return -EIO;
 908	}
 909
 910	if (nor->flags & SNOR_F_NO_READ_CR)
 911		return 0;
 912
 913	cr_written = sr_cr[1];
 914
 915	ret = spi_nor_read_cr(nor, &sr_cr[1]);
 916	if (ret)
 917		return ret;
 918
 919	if (cr_written != sr_cr[1]) {
 920		dev_dbg(nor->dev, "CR: read back test failed\n");
 921		return -EIO;
 922	}
 923
 924	return 0;
 925}
 926
 927/**
 928 * spi_nor_write_16bit_cr_and_check() - Write the Status Register 1 and the
 929 * Configuration Register in one shot. Ensure that the byte written in the
 930 * Configuration Register match the received value, and that the 16-bit Write
 931 * did not affect what was already in the Status Register 1.
 932 * @nor:	pointer to a 'struct spi_nor'.
 933 * @cr:		byte value to be written to the Configuration Register.
 934 *
 935 * Return: 0 on success, -errno otherwise.
 936 */
 937int spi_nor_write_16bit_cr_and_check(struct spi_nor *nor, u8 cr)
 938{
 939	int ret;
 940	u8 *sr_cr = nor->bouncebuf;
 941	u8 sr_written;
 942
 943	/* Keep the current value of the Status Register 1. */
 944	ret = spi_nor_read_sr(nor, sr_cr);
 945	if (ret)
 946		return ret;
 947
 948	sr_cr[1] = cr;
 949
 950	ret = spi_nor_write_sr(nor, sr_cr, 2);
 951	if (ret)
 952		return ret;
 953
 954	sr_written = sr_cr[0];
 955
 956	ret = spi_nor_read_sr(nor, sr_cr);
 957	if (ret)
 958		return ret;
 959
 960	if (sr_written != sr_cr[0]) {
 961		dev_dbg(nor->dev, "SR: Read back test failed\n");
 962		return -EIO;
 963	}
 964
 965	if (nor->flags & SNOR_F_NO_READ_CR)
 966		return 0;
 967
 968	ret = spi_nor_read_cr(nor, &sr_cr[1]);
 969	if (ret)
 970		return ret;
 971
 972	if (cr != sr_cr[1]) {
 973		dev_dbg(nor->dev, "CR: read back test failed\n");
 974		return -EIO;
 975	}
 976
 977	return 0;
 978}
 979
 980/**
 981 * spi_nor_write_sr_and_check() - Write the Status Register 1 and ensure that
 982 * the byte written match the received value without affecting other bits in the
 983 * Status Register 1 and 2.
 984 * @nor:	pointer to a 'struct spi_nor'.
 985 * @sr1:	byte value to be written to the Status Register.
 986 *
 987 * Return: 0 on success, -errno otherwise.
 988 */
 989int spi_nor_write_sr_and_check(struct spi_nor *nor, u8 sr1)
 990{
 991	if (nor->flags & SNOR_F_HAS_16BIT_SR)
 992		return spi_nor_write_16bit_sr_and_check(nor, sr1);
 993
 994	return spi_nor_write_sr1_and_check(nor, sr1);
 995}
 996
 997/**
 998 * spi_nor_write_sr2() - Write the Status Register 2 using the
 999 * SPINOR_OP_WRSR2 (3eh) command.
1000 * @nor:	pointer to 'struct spi_nor'.
1001 * @sr2:	pointer to DMA-able buffer to write to the Status Register 2.
1002 *
1003 * Return: 0 on success, -errno otherwise.
1004 */
1005static int spi_nor_write_sr2(struct spi_nor *nor, const u8 *sr2)
1006{
1007	int ret;
1008
1009	ret = spi_nor_write_enable(nor);
1010	if (ret)
1011		return ret;
1012
1013	if (nor->spimem) {
1014		struct spi_mem_op op = SPI_NOR_WRSR2_OP(sr2);
1015
1016		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1017
1018		ret = spi_mem_exec_op(nor->spimem, &op);
1019	} else {
1020		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR2,
1021						       sr2, 1);
1022	}
1023
1024	if (ret) {
1025		dev_dbg(nor->dev, "error %d writing SR2\n", ret);
1026		return ret;
1027	}
1028
1029	return spi_nor_wait_till_ready(nor);
1030}
1031
1032/**
1033 * spi_nor_read_sr2() - Read the Status Register 2 using the
1034 * SPINOR_OP_RDSR2 (3fh) command.
1035 * @nor:	pointer to 'struct spi_nor'.
1036 * @sr2:	pointer to DMA-able buffer where the value of the
1037 *		Status Register 2 will be written.
1038 *
1039 * Return: 0 on success, -errno otherwise.
1040 */
1041static int spi_nor_read_sr2(struct spi_nor *nor, u8 *sr2)
1042{
1043	int ret;
1044
1045	if (nor->spimem) {
1046		struct spi_mem_op op = SPI_NOR_RDSR2_OP(sr2);
1047
1048		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1049
1050		ret = spi_mem_exec_op(nor->spimem, &op);
1051	} else {
1052		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR2, sr2,
1053						      1);
1054	}
1055
1056	if (ret)
1057		dev_dbg(nor->dev, "error %d reading SR2\n", ret);
1058
1059	return ret;
1060}
1061
1062/**
1063 * spi_nor_erase_die() - Erase the entire die.
1064 * @nor:	pointer to 'struct spi_nor'.
1065 * @addr:	address of the die.
1066 * @die_size:	size of the die.
1067 *
1068 * Return: 0 on success, -errno otherwise.
1069 */
1070static int spi_nor_erase_die(struct spi_nor *nor, loff_t addr, size_t die_size)
1071{
1072	bool multi_die = nor->mtd.size != die_size;
1073	int ret;
1074
1075	dev_dbg(nor->dev, " %lldKiB\n", (long long)(die_size >> 10));
1076
1077	if (nor->spimem) {
1078		struct spi_mem_op op =
1079			SPI_NOR_DIE_ERASE_OP(nor->params->die_erase_opcode,
1080					     nor->addr_nbytes, addr, multi_die);
1081
1082		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1083
1084		ret = spi_mem_exec_op(nor->spimem, &op);
1085	} else {
1086		if (multi_die)
1087			return -EOPNOTSUPP;
1088
1089		ret = spi_nor_controller_ops_write_reg(nor,
1090						       SPINOR_OP_CHIP_ERASE,
1091						       NULL, 0);
1092	}
1093
1094	if (ret)
1095		dev_dbg(nor->dev, "error %d erasing chip\n", ret);
1096
1097	return ret;
1098}
1099
1100static u8 spi_nor_convert_opcode(u8 opcode, const u8 table[][2], size_t size)
1101{
1102	size_t i;
1103
1104	for (i = 0; i < size; i++)
1105		if (table[i][0] == opcode)
1106			return table[i][1];
1107
1108	/* No conversion found, keep input op code. */
1109	return opcode;
1110}
1111
1112u8 spi_nor_convert_3to4_read(u8 opcode)
1113{
1114	static const u8 spi_nor_3to4_read[][2] = {
1115		{ SPINOR_OP_READ,	SPINOR_OP_READ_4B },
1116		{ SPINOR_OP_READ_FAST,	SPINOR_OP_READ_FAST_4B },
1117		{ SPINOR_OP_READ_1_1_2,	SPINOR_OP_READ_1_1_2_4B },
1118		{ SPINOR_OP_READ_1_2_2,	SPINOR_OP_READ_1_2_2_4B },
1119		{ SPINOR_OP_READ_1_1_4,	SPINOR_OP_READ_1_1_4_4B },
1120		{ SPINOR_OP_READ_1_4_4,	SPINOR_OP_READ_1_4_4_4B },
1121		{ SPINOR_OP_READ_1_1_8,	SPINOR_OP_READ_1_1_8_4B },
1122		{ SPINOR_OP_READ_1_8_8,	SPINOR_OP_READ_1_8_8_4B },
1123
1124		{ SPINOR_OP_READ_1_1_1_DTR,	SPINOR_OP_READ_1_1_1_DTR_4B },
1125		{ SPINOR_OP_READ_1_2_2_DTR,	SPINOR_OP_READ_1_2_2_DTR_4B },
1126		{ SPINOR_OP_READ_1_4_4_DTR,	SPINOR_OP_READ_1_4_4_DTR_4B },
1127	};
1128
1129	return spi_nor_convert_opcode(opcode, spi_nor_3to4_read,
1130				      ARRAY_SIZE(spi_nor_3to4_read));
1131}
1132
1133static u8 spi_nor_convert_3to4_program(u8 opcode)
1134{
1135	static const u8 spi_nor_3to4_program[][2] = {
1136		{ SPINOR_OP_PP,		SPINOR_OP_PP_4B },
1137		{ SPINOR_OP_PP_1_1_4,	SPINOR_OP_PP_1_1_4_4B },
1138		{ SPINOR_OP_PP_1_4_4,	SPINOR_OP_PP_1_4_4_4B },
1139		{ SPINOR_OP_PP_1_1_8,	SPINOR_OP_PP_1_1_8_4B },
1140		{ SPINOR_OP_PP_1_8_8,	SPINOR_OP_PP_1_8_8_4B },
1141	};
1142
1143	return spi_nor_convert_opcode(opcode, spi_nor_3to4_program,
1144				      ARRAY_SIZE(spi_nor_3to4_program));
1145}
1146
1147static u8 spi_nor_convert_3to4_erase(u8 opcode)
1148{
1149	static const u8 spi_nor_3to4_erase[][2] = {
1150		{ SPINOR_OP_BE_4K,	SPINOR_OP_BE_4K_4B },
1151		{ SPINOR_OP_BE_32K,	SPINOR_OP_BE_32K_4B },
1152		{ SPINOR_OP_SE,		SPINOR_OP_SE_4B },
1153	};
1154
1155	return spi_nor_convert_opcode(opcode, spi_nor_3to4_erase,
1156				      ARRAY_SIZE(spi_nor_3to4_erase));
1157}
1158
1159static bool spi_nor_has_uniform_erase(const struct spi_nor *nor)
1160{
1161	return !!nor->params->erase_map.uniform_erase_type;
1162}
1163
1164static void spi_nor_set_4byte_opcodes(struct spi_nor *nor)
1165{
1166	nor->read_opcode = spi_nor_convert_3to4_read(nor->read_opcode);
1167	nor->program_opcode = spi_nor_convert_3to4_program(nor->program_opcode);
1168	nor->erase_opcode = spi_nor_convert_3to4_erase(nor->erase_opcode);
1169
1170	if (!spi_nor_has_uniform_erase(nor)) {
1171		struct spi_nor_erase_map *map = &nor->params->erase_map;
1172		struct spi_nor_erase_type *erase;
1173		int i;
1174
1175		for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
1176			erase = &map->erase_type[i];
1177			erase->opcode =
1178				spi_nor_convert_3to4_erase(erase->opcode);
1179		}
1180	}
1181}
1182
1183static int spi_nor_prep(struct spi_nor *nor)
1184{
1185	int ret = 0;
1186
1187	if (nor->controller_ops && nor->controller_ops->prepare)
1188		ret = nor->controller_ops->prepare(nor);
1189
1190	return ret;
1191}
1192
1193static void spi_nor_unprep(struct spi_nor *nor)
1194{
1195	if (nor->controller_ops && nor->controller_ops->unprepare)
1196		nor->controller_ops->unprepare(nor);
1197}
1198
1199static void spi_nor_offset_to_banks(u64 bank_size, loff_t start, size_t len,
1200				    u8 *first, u8 *last)
1201{
1202	/* This is currently safe, the number of banks being very small */
1203	*first = DIV_ROUND_DOWN_ULL(start, bank_size);
1204	*last = DIV_ROUND_DOWN_ULL(start + len - 1, bank_size);
1205}
1206
1207/* Generic helpers for internal locking and serialization */
1208static bool spi_nor_rww_start_io(struct spi_nor *nor)
1209{
1210	struct spi_nor_rww *rww = &nor->rww;
1211	bool start = false;
1212
1213	mutex_lock(&nor->lock);
1214
1215	if (rww->ongoing_io)
1216		goto busy;
1217
1218	rww->ongoing_io = true;
1219	start = true;
1220
1221busy:
1222	mutex_unlock(&nor->lock);
1223	return start;
1224}
1225
1226static void spi_nor_rww_end_io(struct spi_nor *nor)
1227{
1228	mutex_lock(&nor->lock);
1229	nor->rww.ongoing_io = false;
1230	mutex_unlock(&nor->lock);
1231}
1232
1233static int spi_nor_lock_device(struct spi_nor *nor)
1234{
1235	if (!spi_nor_use_parallel_locking(nor))
1236		return 0;
1237
1238	return wait_event_killable(nor->rww.wait, spi_nor_rww_start_io(nor));
1239}
1240
1241static void spi_nor_unlock_device(struct spi_nor *nor)
1242{
1243	if (spi_nor_use_parallel_locking(nor)) {
1244		spi_nor_rww_end_io(nor);
1245		wake_up(&nor->rww.wait);
1246	}
1247}
1248
1249/* Generic helpers for internal locking and serialization */
1250static bool spi_nor_rww_start_exclusive(struct spi_nor *nor)
1251{
1252	struct spi_nor_rww *rww = &nor->rww;
1253	bool start = false;
1254
1255	mutex_lock(&nor->lock);
1256
1257	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
1258		goto busy;
1259
1260	rww->ongoing_io = true;
1261	rww->ongoing_rd = true;
1262	rww->ongoing_pe = true;
1263	start = true;
1264
1265busy:
1266	mutex_unlock(&nor->lock);
1267	return start;
1268}
1269
1270static void spi_nor_rww_end_exclusive(struct spi_nor *nor)
1271{
1272	struct spi_nor_rww *rww = &nor->rww;
1273
1274	mutex_lock(&nor->lock);
1275	rww->ongoing_io = false;
1276	rww->ongoing_rd = false;
1277	rww->ongoing_pe = false;
1278	mutex_unlock(&nor->lock);
1279}
1280
1281int spi_nor_prep_and_lock(struct spi_nor *nor)
1282{
1283	int ret;
1284
1285	ret = spi_nor_prep(nor);
1286	if (ret)
1287		return ret;
1288
1289	if (!spi_nor_use_parallel_locking(nor))
1290		mutex_lock(&nor->lock);
1291	else
1292		ret = wait_event_killable(nor->rww.wait,
1293					  spi_nor_rww_start_exclusive(nor));
1294
1295	return ret;
1296}
1297
1298void spi_nor_unlock_and_unprep(struct spi_nor *nor)
1299{
1300	if (!spi_nor_use_parallel_locking(nor)) {
1301		mutex_unlock(&nor->lock);
1302	} else {
1303		spi_nor_rww_end_exclusive(nor);
1304		wake_up(&nor->rww.wait);
1305	}
1306
1307	spi_nor_unprep(nor);
1308}
1309
1310/* Internal locking helpers for program and erase operations */
1311static bool spi_nor_rww_start_pe(struct spi_nor *nor, loff_t start, size_t len)
1312{
1313	struct spi_nor_rww *rww = &nor->rww;
1314	unsigned int used_banks = 0;
1315	bool started = false;
1316	u8 first, last;
1317	int bank;
1318
1319	mutex_lock(&nor->lock);
1320
1321	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
1322		goto busy;
1323
1324	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1325	for (bank = first; bank <= last; bank++) {
1326		if (rww->used_banks & BIT(bank))
1327			goto busy;
1328
1329		used_banks |= BIT(bank);
1330	}
1331
1332	rww->used_banks |= used_banks;
1333	rww->ongoing_pe = true;
1334	started = true;
1335
1336busy:
1337	mutex_unlock(&nor->lock);
1338	return started;
1339}
1340
1341static void spi_nor_rww_end_pe(struct spi_nor *nor, loff_t start, size_t len)
1342{
1343	struct spi_nor_rww *rww = &nor->rww;
1344	u8 first, last;
1345	int bank;
1346
1347	mutex_lock(&nor->lock);
1348
1349	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1350	for (bank = first; bank <= last; bank++)
1351		rww->used_banks &= ~BIT(bank);
1352
1353	rww->ongoing_pe = false;
1354
1355	mutex_unlock(&nor->lock);
1356}
1357
1358static int spi_nor_prep_and_lock_pe(struct spi_nor *nor, loff_t start, size_t len)
1359{
1360	int ret;
1361
1362	ret = spi_nor_prep(nor);
1363	if (ret)
1364		return ret;
1365
1366	if (!spi_nor_use_parallel_locking(nor))
1367		mutex_lock(&nor->lock);
1368	else
1369		ret = wait_event_killable(nor->rww.wait,
1370					  spi_nor_rww_start_pe(nor, start, len));
1371
1372	return ret;
1373}
1374
1375static void spi_nor_unlock_and_unprep_pe(struct spi_nor *nor, loff_t start, size_t len)
1376{
1377	if (!spi_nor_use_parallel_locking(nor)) {
1378		mutex_unlock(&nor->lock);
1379	} else {
1380		spi_nor_rww_end_pe(nor, start, len);
1381		wake_up(&nor->rww.wait);
1382	}
1383
1384	spi_nor_unprep(nor);
1385}
1386
1387/* Internal locking helpers for read operations */
1388static bool spi_nor_rww_start_rd(struct spi_nor *nor, loff_t start, size_t len)
1389{
1390	struct spi_nor_rww *rww = &nor->rww;
1391	unsigned int used_banks = 0;
1392	bool started = false;
1393	u8 first, last;
1394	int bank;
1395
1396	mutex_lock(&nor->lock);
1397
1398	if (rww->ongoing_io || rww->ongoing_rd)
1399		goto busy;
1400
1401	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1402	for (bank = first; bank <= last; bank++) {
1403		if (rww->used_banks & BIT(bank))
1404			goto busy;
1405
1406		used_banks |= BIT(bank);
1407	}
1408
1409	rww->used_banks |= used_banks;
1410	rww->ongoing_io = true;
1411	rww->ongoing_rd = true;
1412	started = true;
1413
1414busy:
1415	mutex_unlock(&nor->lock);
1416	return started;
1417}
1418
1419static void spi_nor_rww_end_rd(struct spi_nor *nor, loff_t start, size_t len)
1420{
1421	struct spi_nor_rww *rww = &nor->rww;
1422	u8 first, last;
1423	int bank;
1424
1425	mutex_lock(&nor->lock);
1426
1427	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1428	for (bank = first; bank <= last; bank++)
1429		nor->rww.used_banks &= ~BIT(bank);
1430
1431	rww->ongoing_io = false;
1432	rww->ongoing_rd = false;
1433
1434	mutex_unlock(&nor->lock);
1435}
1436
1437static int spi_nor_prep_and_lock_rd(struct spi_nor *nor, loff_t start, size_t len)
1438{
1439	int ret;
1440
1441	ret = spi_nor_prep(nor);
1442	if (ret)
1443		return ret;
1444
1445	if (!spi_nor_use_parallel_locking(nor))
1446		mutex_lock(&nor->lock);
1447	else
1448		ret = wait_event_killable(nor->rww.wait,
1449					  spi_nor_rww_start_rd(nor, start, len));
1450
1451	return ret;
1452}
1453
1454static void spi_nor_unlock_and_unprep_rd(struct spi_nor *nor, loff_t start, size_t len)
1455{
1456	if (!spi_nor_use_parallel_locking(nor)) {
1457		mutex_unlock(&nor->lock);
1458	} else {
1459		spi_nor_rww_end_rd(nor, start, len);
1460		wake_up(&nor->rww.wait);
1461	}
1462
1463	spi_nor_unprep(nor);
1464}
1465
1466static u32 spi_nor_convert_addr(struct spi_nor *nor, loff_t addr)
1467{
1468	if (!nor->params->convert_addr)
1469		return addr;
1470
1471	return nor->params->convert_addr(nor, addr);
1472}
1473
1474/*
1475 * Initiate the erasure of a single sector
1476 */
1477int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
1478{
1479	int i;
1480
1481	addr = spi_nor_convert_addr(nor, addr);
1482
1483	if (nor->spimem) {
1484		struct spi_mem_op op =
1485			SPI_NOR_SECTOR_ERASE_OP(nor->erase_opcode,
1486						nor->addr_nbytes, addr);
1487
1488		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1489
1490		return spi_mem_exec_op(nor->spimem, &op);
1491	} else if (nor->controller_ops->erase) {
1492		return spi_nor_controller_ops_erase(nor, addr);
1493	}
1494
1495	/*
1496	 * Default implementation, if driver doesn't have a specialized HW
1497	 * control
1498	 */
1499	for (i = nor->addr_nbytes - 1; i >= 0; i--) {
1500		nor->bouncebuf[i] = addr & 0xff;
1501		addr >>= 8;
1502	}
1503
1504	return spi_nor_controller_ops_write_reg(nor, nor->erase_opcode,
1505						nor->bouncebuf, nor->addr_nbytes);
1506}
1507
1508/**
1509 * spi_nor_div_by_erase_size() - calculate remainder and update new dividend
1510 * @erase:	pointer to a structure that describes a SPI NOR erase type
1511 * @dividend:	dividend value
1512 * @remainder:	pointer to u32 remainder (will be updated)
1513 *
1514 * Return: the result of the division
1515 */
1516static u64 spi_nor_div_by_erase_size(const struct spi_nor_erase_type *erase,
1517				     u64 dividend, u32 *remainder)
1518{
1519	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
1520	*remainder = (u32)dividend & erase->size_mask;
1521	return dividend >> erase->size_shift;
1522}
1523
1524/**
1525 * spi_nor_find_best_erase_type() - find the best erase type for the given
1526 *				    offset in the serial flash memory and the
1527 *				    number of bytes to erase. The region in
1528 *				    which the address fits is expected to be
1529 *				    provided.
1530 * @map:	the erase map of the SPI NOR
1531 * @region:	pointer to a structure that describes a SPI NOR erase region
1532 * @addr:	offset in the serial flash memory
1533 * @len:	number of bytes to erase
1534 *
1535 * Return: a pointer to the best fitted erase type, NULL otherwise.
1536 */
1537static const struct spi_nor_erase_type *
1538spi_nor_find_best_erase_type(const struct spi_nor_erase_map *map,
1539			     const struct spi_nor_erase_region *region,
1540			     u64 addr, u32 len)
1541{
1542	const struct spi_nor_erase_type *erase;
1543	u32 rem;
1544	int i;
1545	u8 erase_mask = region->offset & SNOR_ERASE_TYPE_MASK;
1546
1547	/*
1548	 * Erase types are ordered by size, with the smallest erase type at
1549	 * index 0.
1550	 */
1551	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
1552		/* Does the erase region support the tested erase type? */
1553		if (!(erase_mask & BIT(i)))
1554			continue;
1555
1556		erase = &map->erase_type[i];
1557		if (!erase->size)
1558			continue;
1559
1560		/* Alignment is not mandatory for overlaid regions */
1561		if (region->offset & SNOR_OVERLAID_REGION &&
1562		    region->size <= len)
1563			return erase;
1564
1565		/* Don't erase more than what the user has asked for. */
1566		if (erase->size > len)
1567			continue;
1568
1569		spi_nor_div_by_erase_size(erase, addr, &rem);
1570		if (!rem)
1571			return erase;
1572	}
1573
1574	return NULL;
1575}
1576
1577static u64 spi_nor_region_is_last(const struct spi_nor_erase_region *region)
1578{
1579	return region->offset & SNOR_LAST_REGION;
1580}
1581
1582static u64 spi_nor_region_end(const struct spi_nor_erase_region *region)
1583{
1584	return (region->offset & ~SNOR_ERASE_FLAGS_MASK) + region->size;
1585}
1586
1587/**
1588 * spi_nor_region_next() - get the next spi nor region
1589 * @region:	pointer to a structure that describes a SPI NOR erase region
1590 *
1591 * Return: the next spi nor region or NULL if last region.
1592 */
1593struct spi_nor_erase_region *
1594spi_nor_region_next(struct spi_nor_erase_region *region)
1595{
1596	if (spi_nor_region_is_last(region))
1597		return NULL;
1598	region++;
1599	return region;
1600}
1601
1602/**
1603 * spi_nor_find_erase_region() - find the region of the serial flash memory in
1604 *				 which the offset fits
1605 * @map:	the erase map of the SPI NOR
1606 * @addr:	offset in the serial flash memory
1607 *
1608 * Return: a pointer to the spi_nor_erase_region struct, ERR_PTR(-errno)
1609 *	   otherwise.
1610 */
1611static struct spi_nor_erase_region *
1612spi_nor_find_erase_region(const struct spi_nor_erase_map *map, u64 addr)
1613{
1614	struct spi_nor_erase_region *region = map->regions;
1615	u64 region_start = region->offset & ~SNOR_ERASE_FLAGS_MASK;
1616	u64 region_end = region_start + region->size;
1617
1618	while (addr < region_start || addr >= region_end) {
1619		region = spi_nor_region_next(region);
1620		if (!region)
1621			return ERR_PTR(-EINVAL);
1622
1623		region_start = region->offset & ~SNOR_ERASE_FLAGS_MASK;
1624		region_end = region_start + region->size;
1625	}
1626
1627	return region;
1628}
1629
1630/**
1631 * spi_nor_init_erase_cmd() - initialize an erase command
1632 * @region:	pointer to a structure that describes a SPI NOR erase region
1633 * @erase:	pointer to a structure that describes a SPI NOR erase type
1634 *
1635 * Return: the pointer to the allocated erase command, ERR_PTR(-errno)
1636 *	   otherwise.
1637 */
1638static struct spi_nor_erase_command *
1639spi_nor_init_erase_cmd(const struct spi_nor_erase_region *region,
1640		       const struct spi_nor_erase_type *erase)
1641{
1642	struct spi_nor_erase_command *cmd;
1643
1644	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
1645	if (!cmd)
1646		return ERR_PTR(-ENOMEM);
1647
1648	INIT_LIST_HEAD(&cmd->list);
1649	cmd->opcode = erase->opcode;
1650	cmd->count = 1;
1651
1652	if (region->offset & SNOR_OVERLAID_REGION)
1653		cmd->size = region->size;
1654	else
1655		cmd->size = erase->size;
1656
1657	return cmd;
1658}
1659
1660/**
1661 * spi_nor_destroy_erase_cmd_list() - destroy erase command list
1662 * @erase_list:	list of erase commands
1663 */
1664static void spi_nor_destroy_erase_cmd_list(struct list_head *erase_list)
1665{
1666	struct spi_nor_erase_command *cmd, *next;
1667
1668	list_for_each_entry_safe(cmd, next, erase_list, list) {
1669		list_del(&cmd->list);
1670		kfree(cmd);
1671	}
1672}
1673
1674/**
1675 * spi_nor_init_erase_cmd_list() - initialize erase command list
1676 * @nor:	pointer to a 'struct spi_nor'
1677 * @erase_list:	list of erase commands to be executed once we validate that the
1678 *		erase can be performed
1679 * @addr:	offset in the serial flash memory
1680 * @len:	number of bytes to erase
1681 *
1682 * Builds the list of best fitted erase commands and verifies if the erase can
1683 * be performed.
1684 *
1685 * Return: 0 on success, -errno otherwise.
1686 */
1687static int spi_nor_init_erase_cmd_list(struct spi_nor *nor,
1688				       struct list_head *erase_list,
1689				       u64 addr, u32 len)
1690{
1691	const struct spi_nor_erase_map *map = &nor->params->erase_map;
1692	const struct spi_nor_erase_type *erase, *prev_erase = NULL;
1693	struct spi_nor_erase_region *region;
1694	struct spi_nor_erase_command *cmd = NULL;
1695	u64 region_end;
1696	int ret = -EINVAL;
1697
1698	region = spi_nor_find_erase_region(map, addr);
1699	if (IS_ERR(region))
1700		return PTR_ERR(region);
1701
1702	region_end = spi_nor_region_end(region);
1703
1704	while (len) {
1705		erase = spi_nor_find_best_erase_type(map, region, addr, len);
1706		if (!erase)
1707			goto destroy_erase_cmd_list;
1708
1709		if (prev_erase != erase ||
1710		    erase->size != cmd->size ||
1711		    region->offset & SNOR_OVERLAID_REGION) {
1712			cmd = spi_nor_init_erase_cmd(region, erase);
1713			if (IS_ERR(cmd)) {
1714				ret = PTR_ERR(cmd);
1715				goto destroy_erase_cmd_list;
1716			}
1717
1718			list_add_tail(&cmd->list, erase_list);
1719		} else {
1720			cmd->count++;
1721		}
1722
1723		addr += cmd->size;
1724		len -= cmd->size;
1725
1726		if (len && addr >= region_end) {
1727			region = spi_nor_region_next(region);
1728			if (!region)
1729				goto destroy_erase_cmd_list;
1730			region_end = spi_nor_region_end(region);
1731		}
1732
1733		prev_erase = erase;
1734	}
1735
1736	return 0;
1737
1738destroy_erase_cmd_list:
1739	spi_nor_destroy_erase_cmd_list(erase_list);
1740	return ret;
1741}
1742
1743/**
1744 * spi_nor_erase_multi_sectors() - perform a non-uniform erase
1745 * @nor:	pointer to a 'struct spi_nor'
1746 * @addr:	offset in the serial flash memory
1747 * @len:	number of bytes to erase
1748 *
1749 * Build a list of best fitted erase commands and execute it once we validate
1750 * that the erase can be performed.
1751 *
1752 * Return: 0 on success, -errno otherwise.
1753 */
1754static int spi_nor_erase_multi_sectors(struct spi_nor *nor, u64 addr, u32 len)
1755{
1756	LIST_HEAD(erase_list);
1757	struct spi_nor_erase_command *cmd, *next;
1758	int ret;
1759
1760	ret = spi_nor_init_erase_cmd_list(nor, &erase_list, addr, len);
1761	if (ret)
1762		return ret;
1763
1764	list_for_each_entry_safe(cmd, next, &erase_list, list) {
1765		nor->erase_opcode = cmd->opcode;
1766		while (cmd->count) {
1767			dev_vdbg(nor->dev, "erase_cmd->size = 0x%08x, erase_cmd->opcode = 0x%02x, erase_cmd->count = %u\n",
1768				 cmd->size, cmd->opcode, cmd->count);
1769
1770			ret = spi_nor_lock_device(nor);
1771			if (ret)
1772				goto destroy_erase_cmd_list;
1773
1774			ret = spi_nor_write_enable(nor);
1775			if (ret) {
1776				spi_nor_unlock_device(nor);
1777				goto destroy_erase_cmd_list;
1778			}
1779
1780			ret = spi_nor_erase_sector(nor, addr);
1781			spi_nor_unlock_device(nor);
1782			if (ret)
1783				goto destroy_erase_cmd_list;
1784
1785			ret = spi_nor_wait_till_ready(nor);
1786			if (ret)
1787				goto destroy_erase_cmd_list;
1788
1789			addr += cmd->size;
1790			cmd->count--;
1791		}
1792		list_del(&cmd->list);
1793		kfree(cmd);
1794	}
1795
1796	return 0;
1797
1798destroy_erase_cmd_list:
1799	spi_nor_destroy_erase_cmd_list(&erase_list);
1800	return ret;
1801}
1802
1803static int spi_nor_erase_dice(struct spi_nor *nor, loff_t addr,
1804			      size_t len, size_t die_size)
1805{
1806	unsigned long timeout;
1807	int ret;
1808
1809	/*
1810	 * Scale the timeout linearly with the size of the flash, with
1811	 * a minimum calibrated to an old 2MB flash. We could try to
1812	 * pull these from CFI/SFDP, but these values should be good
1813	 * enough for now.
1814	 */
1815	timeout = max(CHIP_ERASE_2MB_READY_WAIT_JIFFIES,
1816		      CHIP_ERASE_2MB_READY_WAIT_JIFFIES *
1817		      (unsigned long)(nor->mtd.size / SZ_2M));
1818
1819	do {
1820		ret = spi_nor_lock_device(nor);
1821		if (ret)
1822			return ret;
1823
1824		ret = spi_nor_write_enable(nor);
1825		if (ret) {
1826			spi_nor_unlock_device(nor);
1827			return ret;
1828		}
1829
1830		ret = spi_nor_erase_die(nor, addr, die_size);
1831
1832		spi_nor_unlock_device(nor);
1833		if (ret)
1834			return ret;
1835
1836		ret = spi_nor_wait_till_ready_with_timeout(nor, timeout);
1837		if (ret)
1838			return ret;
1839
1840		addr += die_size;
1841		len -= die_size;
1842
1843	} while (len);
1844
1845	return 0;
1846}
1847
1848/*
1849 * Erase an address range on the nor chip.  The address range may extend
1850 * one or more erase sectors. Return an error if there is a problem erasing.
1851 */
1852static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
1853{
1854	struct spi_nor *nor = mtd_to_spi_nor(mtd);
1855	u8 n_dice = nor->params->n_dice;
1856	bool multi_die_erase = false;
1857	u32 addr, len, rem;
1858	size_t die_size;
1859	int ret;
1860
1861	dev_dbg(nor->dev, "at 0x%llx, len %lld\n", (long long)instr->addr,
1862			(long long)instr->len);
1863
1864	if (spi_nor_has_uniform_erase(nor)) {
1865		div_u64_rem(instr->len, mtd->erasesize, &rem);
1866		if (rem)
1867			return -EINVAL;
1868	}
1869
1870	addr = instr->addr;
1871	len = instr->len;
1872
1873	if (n_dice) {
1874		die_size = div_u64(mtd->size, n_dice);
1875		if (!(len & (die_size - 1)) && !(addr & (die_size - 1)))
1876			multi_die_erase = true;
1877	} else {
1878		die_size = mtd->size;
1879	}
1880
1881	ret = spi_nor_prep_and_lock_pe(nor, instr->addr, instr->len);
1882	if (ret)
1883		return ret;
1884
1885	/* chip (die) erase? */
1886	if ((len == mtd->size && !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) ||
1887	    multi_die_erase) {
1888		ret = spi_nor_erase_dice(nor, addr, len, die_size);
1889		if (ret)
1890			goto erase_err;
1891
1892	/* REVISIT in some cases we could speed up erasing large regions
1893	 * by using SPINOR_OP_SE instead of SPINOR_OP_BE_4K.  We may have set up
1894	 * to use "small sector erase", but that's not always optimal.
1895	 */
1896
1897	/* "sector"-at-a-time erase */
1898	} else if (spi_nor_has_uniform_erase(nor)) {
1899		while (len) {
1900			ret = spi_nor_lock_device(nor);
1901			if (ret)
1902				goto erase_err;
1903
1904			ret = spi_nor_write_enable(nor);
1905			if (ret) {
1906				spi_nor_unlock_device(nor);
1907				goto erase_err;
1908			}
1909
1910			ret = spi_nor_erase_sector(nor, addr);
1911			spi_nor_unlock_device(nor);
1912			if (ret)
1913				goto erase_err;
1914
1915			ret = spi_nor_wait_till_ready(nor);
1916			if (ret)
1917				goto erase_err;
1918
1919			addr += mtd->erasesize;
1920			len -= mtd->erasesize;
1921		}
1922
1923	/* erase multiple sectors */
1924	} else {
1925		ret = spi_nor_erase_multi_sectors(nor, addr, len);
1926		if (ret)
1927			goto erase_err;
1928	}
1929
1930	ret = spi_nor_write_disable(nor);
1931
1932erase_err:
1933	spi_nor_unlock_and_unprep_pe(nor, instr->addr, instr->len);
1934
1935	return ret;
1936}
1937
1938/**
1939 * spi_nor_sr1_bit6_quad_enable() - Set the Quad Enable BIT(6) in the Status
1940 * Register 1.
1941 * @nor:	pointer to a 'struct spi_nor'
1942 *
1943 * Bit 6 of the Status Register 1 is the QE bit for Macronix like QSPI memories.
1944 *
1945 * Return: 0 on success, -errno otherwise.
1946 */
1947int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor)
1948{
1949	int ret;
1950
1951	ret = spi_nor_read_sr(nor, nor->bouncebuf);
1952	if (ret)
1953		return ret;
1954
1955	if (nor->bouncebuf[0] & SR1_QUAD_EN_BIT6)
1956		return 0;
1957
1958	nor->bouncebuf[0] |= SR1_QUAD_EN_BIT6;
1959
1960	return spi_nor_write_sr1_and_check(nor, nor->bouncebuf[0]);
1961}
1962
1963/**
1964 * spi_nor_sr2_bit1_quad_enable() - set the Quad Enable BIT(1) in the Status
1965 * Register 2.
1966 * @nor:       pointer to a 'struct spi_nor'.
1967 *
1968 * Bit 1 of the Status Register 2 is the QE bit for Spansion like QSPI memories.
1969 *
1970 * Return: 0 on success, -errno otherwise.
1971 */
1972int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor)
1973{
1974	int ret;
1975
1976	if (nor->flags & SNOR_F_NO_READ_CR)
1977		return spi_nor_write_16bit_cr_and_check(nor, SR2_QUAD_EN_BIT1);
1978
1979	ret = spi_nor_read_cr(nor, nor->bouncebuf);
1980	if (ret)
1981		return ret;
1982
1983	if (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)
1984		return 0;
1985
1986	nor->bouncebuf[0] |= SR2_QUAD_EN_BIT1;
1987
1988	return spi_nor_write_16bit_cr_and_check(nor, nor->bouncebuf[0]);
1989}
1990
1991/**
1992 * spi_nor_sr2_bit7_quad_enable() - set QE bit in Status Register 2.
1993 * @nor:	pointer to a 'struct spi_nor'
1994 *
1995 * Set the Quad Enable (QE) bit in the Status Register 2.
1996 *
1997 * This is one of the procedures to set the QE bit described in the SFDP
1998 * (JESD216 rev B) specification but no manufacturer using this procedure has
1999 * been identified yet, hence the name of the function.
2000 *
2001 * Return: 0 on success, -errno otherwise.
2002 */
2003int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor)
2004{
2005	u8 *sr2 = nor->bouncebuf;
2006	int ret;
2007	u8 sr2_written;
2008
2009	/* Check current Quad Enable bit value. */
2010	ret = spi_nor_read_sr2(nor, sr2);
2011	if (ret)
2012		return ret;
2013	if (*sr2 & SR2_QUAD_EN_BIT7)
2014		return 0;
2015
2016	/* Update the Quad Enable bit. */
2017	*sr2 |= SR2_QUAD_EN_BIT7;
2018
2019	ret = spi_nor_write_sr2(nor, sr2);
2020	if (ret)
2021		return ret;
2022
2023	sr2_written = *sr2;
2024
2025	/* Read back and check it. */
2026	ret = spi_nor_read_sr2(nor, sr2);
2027	if (ret)
2028		return ret;
2029
2030	if (*sr2 != sr2_written) {
2031		dev_dbg(nor->dev, "SR2: Read back test failed\n");
2032		return -EIO;
2033	}
2034
2035	return 0;
2036}
2037
2038static const struct spi_nor_manufacturer *manufacturers[] = {
2039	&spi_nor_atmel,
2040	&spi_nor_eon,
2041	&spi_nor_esmt,
2042	&spi_nor_everspin,
2043	&spi_nor_gigadevice,
2044	&spi_nor_intel,
2045	&spi_nor_issi,
2046	&spi_nor_macronix,
2047	&spi_nor_micron,
2048	&spi_nor_st,
2049	&spi_nor_spansion,
2050	&spi_nor_sst,
2051	&spi_nor_winbond,
2052	&spi_nor_xilinx,
2053	&spi_nor_xmc,
2054};
2055
2056static const struct flash_info spi_nor_generic_flash = {
2057	.name = "spi-nor-generic",
2058};
2059
2060static const struct flash_info *spi_nor_match_id(struct spi_nor *nor,
2061						 const u8 *id)
2062{
2063	const struct flash_info *part;
2064	unsigned int i, j;
2065
2066	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
2067		for (j = 0; j < manufacturers[i]->nparts; j++) {
2068			part = &manufacturers[i]->parts[j];
2069			if (part->id &&
2070			    !memcmp(part->id->bytes, id, part->id->len)) {
2071				nor->manufacturer = manufacturers[i];
2072				return part;
2073			}
2074		}
2075	}
2076
2077	return NULL;
2078}
2079
2080static const struct flash_info *spi_nor_detect(struct spi_nor *nor)
2081{
2082	const struct flash_info *info;
2083	u8 *id = nor->bouncebuf;
2084	int ret;
2085
2086	ret = spi_nor_read_id(nor, 0, 0, id, nor->reg_proto);
2087	if (ret) {
2088		dev_dbg(nor->dev, "error %d reading JEDEC ID\n", ret);
2089		return ERR_PTR(ret);
2090	}
2091
2092	/* Cache the complete flash ID. */
2093	nor->id = devm_kmemdup(nor->dev, id, SPI_NOR_MAX_ID_LEN, GFP_KERNEL);
2094	if (!nor->id)
2095		return ERR_PTR(-ENOMEM);
2096
2097	info = spi_nor_match_id(nor, id);
2098
2099	/* Fallback to a generic flash described only by its SFDP data. */
2100	if (!info) {
2101		ret = spi_nor_check_sfdp_signature(nor);
2102		if (!ret)
2103			info = &spi_nor_generic_flash;
2104	}
2105
2106	if (!info) {
2107		dev_err(nor->dev, "unrecognized JEDEC id bytes: %*ph\n",
2108			SPI_NOR_MAX_ID_LEN, id);
2109		return ERR_PTR(-ENODEV);
2110	}
2111	return info;
2112}
2113
2114static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
2115			size_t *retlen, u_char *buf)
2116{
2117	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2118	loff_t from_lock = from;
2119	size_t len_lock = len;
2120	ssize_t ret;
2121
2122	dev_dbg(nor->dev, "from 0x%08x, len %zd\n", (u32)from, len);
2123
2124	ret = spi_nor_prep_and_lock_rd(nor, from_lock, len_lock);
2125	if (ret)
2126		return ret;
2127
2128	while (len) {
2129		loff_t addr = from;
2130
2131		addr = spi_nor_convert_addr(nor, addr);
2132
2133		ret = spi_nor_read_data(nor, addr, len, buf);
2134		if (ret == 0) {
2135			/* We shouldn't see 0-length reads */
2136			ret = -EIO;
2137			goto read_err;
2138		}
2139		if (ret < 0)
2140			goto read_err;
2141
2142		WARN_ON(ret > len);
2143		*retlen += ret;
2144		buf += ret;
2145		from += ret;
2146		len -= ret;
2147	}
2148	ret = 0;
2149
2150read_err:
2151	spi_nor_unlock_and_unprep_rd(nor, from_lock, len_lock);
2152
2153	return ret;
2154}
2155
2156/*
2157 * Write an address range to the nor chip.  Data must be written in
2158 * FLASH_PAGESIZE chunks.  The address range may be any size provided
2159 * it is within the physical boundaries.
2160 */
2161static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
2162	size_t *retlen, const u_char *buf)
2163{
2164	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2165	size_t page_offset, page_remain, i;
2166	ssize_t ret;
2167	u32 page_size = nor->params->page_size;
2168
2169	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
2170
2171	ret = spi_nor_prep_and_lock_pe(nor, to, len);
2172	if (ret)
2173		return ret;
2174
2175	for (i = 0; i < len; ) {
2176		ssize_t written;
2177		loff_t addr = to + i;
2178
2179		/*
2180		 * If page_size is a power of two, the offset can be quickly
2181		 * calculated with an AND operation. On the other cases we
2182		 * need to do a modulus operation (more expensive).
2183		 */
2184		if (is_power_of_2(page_size)) {
2185			page_offset = addr & (page_size - 1);
2186		} else {
2187			u64 aux = addr;
2188
2189			page_offset = do_div(aux, page_size);
2190		}
2191		/* the size of data remaining on the first page */
2192		page_remain = min_t(size_t, page_size - page_offset, len - i);
2193
2194		addr = spi_nor_convert_addr(nor, addr);
2195
2196		ret = spi_nor_lock_device(nor);
2197		if (ret)
2198			goto write_err;
2199
2200		ret = spi_nor_write_enable(nor);
2201		if (ret) {
2202			spi_nor_unlock_device(nor);
2203			goto write_err;
2204		}
2205
2206		ret = spi_nor_write_data(nor, addr, page_remain, buf + i);
2207		spi_nor_unlock_device(nor);
2208		if (ret < 0)
2209			goto write_err;
2210		written = ret;
2211
2212		ret = spi_nor_wait_till_ready(nor);
2213		if (ret)
2214			goto write_err;
2215		*retlen += written;
2216		i += written;
2217	}
2218
2219write_err:
2220	spi_nor_unlock_and_unprep_pe(nor, to, len);
2221
2222	return ret;
2223}
2224
2225static int spi_nor_check(struct spi_nor *nor)
2226{
2227	if (!nor->dev ||
2228	    (!nor->spimem && !nor->controller_ops) ||
2229	    (!nor->spimem && nor->controller_ops &&
2230	    (!nor->controller_ops->read ||
2231	     !nor->controller_ops->write ||
2232	     !nor->controller_ops->read_reg ||
2233	     !nor->controller_ops->write_reg))) {
2234		pr_err("spi-nor: please fill all the necessary fields!\n");
2235		return -EINVAL;
2236	}
2237
2238	if (nor->spimem && nor->controller_ops) {
2239		dev_err(nor->dev, "nor->spimem and nor->controller_ops are mutually exclusive, please set just one of them.\n");
2240		return -EINVAL;
2241	}
2242
2243	return 0;
2244}
2245
2246void
2247spi_nor_set_read_settings(struct spi_nor_read_command *read,
2248			  u8 num_mode_clocks,
2249			  u8 num_wait_states,
2250			  u8 opcode,
2251			  enum spi_nor_protocol proto)
2252{
2253	read->num_mode_clocks = num_mode_clocks;
2254	read->num_wait_states = num_wait_states;
2255	read->opcode = opcode;
2256	read->proto = proto;
2257}
2258
2259void spi_nor_set_pp_settings(struct spi_nor_pp_command *pp, u8 opcode,
2260			     enum spi_nor_protocol proto)
2261{
2262	pp->opcode = opcode;
2263	pp->proto = proto;
2264}
2265
2266static int spi_nor_hwcaps2cmd(u32 hwcaps, const int table[][2], size_t size)
2267{
2268	size_t i;
2269
2270	for (i = 0; i < size; i++)
2271		if (table[i][0] == (int)hwcaps)
2272			return table[i][1];
2273
2274	return -EINVAL;
2275}
2276
2277int spi_nor_hwcaps_read2cmd(u32 hwcaps)
2278{
2279	static const int hwcaps_read2cmd[][2] = {
2280		{ SNOR_HWCAPS_READ,		SNOR_CMD_READ },
2281		{ SNOR_HWCAPS_READ_FAST,	SNOR_CMD_READ_FAST },
2282		{ SNOR_HWCAPS_READ_1_1_1_DTR,	SNOR_CMD_READ_1_1_1_DTR },
2283		{ SNOR_HWCAPS_READ_1_1_2,	SNOR_CMD_READ_1_1_2 },
2284		{ SNOR_HWCAPS_READ_1_2_2,	SNOR_CMD_READ_1_2_2 },
2285		{ SNOR_HWCAPS_READ_2_2_2,	SNOR_CMD_READ_2_2_2 },
2286		{ SNOR_HWCAPS_READ_1_2_2_DTR,	SNOR_CMD_READ_1_2_2_DTR },
2287		{ SNOR_HWCAPS_READ_1_1_4,	SNOR_CMD_READ_1_1_4 },
2288		{ SNOR_HWCAPS_READ_1_4_4,	SNOR_CMD_READ_1_4_4 },
2289		{ SNOR_HWCAPS_READ_4_4_4,	SNOR_CMD_READ_4_4_4 },
2290		{ SNOR_HWCAPS_READ_1_4_4_DTR,	SNOR_CMD_READ_1_4_4_DTR },
2291		{ SNOR_HWCAPS_READ_1_1_8,	SNOR_CMD_READ_1_1_8 },
2292		{ SNOR_HWCAPS_READ_1_8_8,	SNOR_CMD_READ_1_8_8 },
2293		{ SNOR_HWCAPS_READ_8_8_8,	SNOR_CMD_READ_8_8_8 },
2294		{ SNOR_HWCAPS_READ_1_8_8_DTR,	SNOR_CMD_READ_1_8_8_DTR },
2295		{ SNOR_HWCAPS_READ_8_8_8_DTR,	SNOR_CMD_READ_8_8_8_DTR },
2296	};
2297
2298	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_read2cmd,
2299				  ARRAY_SIZE(hwcaps_read2cmd));
2300}
2301
2302int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
2303{
2304	static const int hwcaps_pp2cmd[][2] = {
2305		{ SNOR_HWCAPS_PP,		SNOR_CMD_PP },
2306		{ SNOR_HWCAPS_PP_1_1_4,		SNOR_CMD_PP_1_1_4 },
2307		{ SNOR_HWCAPS_PP_1_4_4,		SNOR_CMD_PP_1_4_4 },
2308		{ SNOR_HWCAPS_PP_4_4_4,		SNOR_CMD_PP_4_4_4 },
2309		{ SNOR_HWCAPS_PP_1_1_8,		SNOR_CMD_PP_1_1_8 },
2310		{ SNOR_HWCAPS_PP_1_8_8,		SNOR_CMD_PP_1_8_8 },
2311		{ SNOR_HWCAPS_PP_8_8_8,		SNOR_CMD_PP_8_8_8 },
2312		{ SNOR_HWCAPS_PP_8_8_8_DTR,	SNOR_CMD_PP_8_8_8_DTR },
2313	};
2314
2315	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_pp2cmd,
2316				  ARRAY_SIZE(hwcaps_pp2cmd));
2317}
2318
2319/**
2320 * spi_nor_spimem_check_op - check if the operation is supported
2321 *                           by controller
2322 *@nor:        pointer to a 'struct spi_nor'
2323 *@op:         pointer to op template to be checked
2324 *
2325 * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2326 */
2327static int spi_nor_spimem_check_op(struct spi_nor *nor,
2328				   struct spi_mem_op *op)
2329{
2330	/*
2331	 * First test with 4 address bytes. The opcode itself might
2332	 * be a 3B addressing opcode but we don't care, because
2333	 * SPI controller implementation should not check the opcode,
2334	 * but just the sequence.
2335	 */
2336	op->addr.nbytes = 4;
2337	if (!spi_mem_supports_op(nor->spimem, op)) {
2338		if (nor->params->size > SZ_16M)
2339			return -EOPNOTSUPP;
2340
2341		/* If flash size <= 16MB, 3 address bytes are sufficient */
2342		op->addr.nbytes = 3;
2343		if (!spi_mem_supports_op(nor->spimem, op))
2344			return -EOPNOTSUPP;
2345	}
2346
2347	return 0;
2348}
2349
2350/**
2351 * spi_nor_spimem_check_readop - check if the read op is supported
2352 *                               by controller
2353 *@nor:         pointer to a 'struct spi_nor'
2354 *@read:        pointer to op template to be checked
2355 *
2356 * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2357 */
2358static int spi_nor_spimem_check_readop(struct spi_nor *nor,
2359				       const struct spi_nor_read_command *read)
2360{
2361	struct spi_mem_op op = SPI_NOR_READ_OP(read->opcode);
2362
2363	spi_nor_spimem_setup_op(nor, &op, read->proto);
2364
2365	/* convert the dummy cycles to the number of bytes */
2366	op.dummy.nbytes = (read->num_mode_clocks + read->num_wait_states) *
2367			  op.dummy.buswidth / 8;
2368	if (spi_nor_protocol_is_dtr(nor->read_proto))
2369		op.dummy.nbytes *= 2;
2370
2371	return spi_nor_spimem_check_op(nor, &op);
2372}
2373
2374/**
2375 * spi_nor_spimem_check_pp - check if the page program op is supported
2376 *                           by controller
2377 *@nor:         pointer to a 'struct spi_nor'
2378 *@pp:          pointer to op template to be checked
2379 *
2380 * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2381 */
2382static int spi_nor_spimem_check_pp(struct spi_nor *nor,
2383				   const struct spi_nor_pp_command *pp)
2384{
2385	struct spi_mem_op op = SPI_NOR_PP_OP(pp->opcode);
2386
2387	spi_nor_spimem_setup_op(nor, &op, pp->proto);
2388
2389	return spi_nor_spimem_check_op(nor, &op);
2390}
2391
2392/**
2393 * spi_nor_spimem_adjust_hwcaps - Find optimal Read/Write protocol
2394 *                                based on SPI controller capabilities
2395 * @nor:        pointer to a 'struct spi_nor'
2396 * @hwcaps:     pointer to resulting capabilities after adjusting
2397 *              according to controller and flash's capability
2398 */
2399static void
2400spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor, u32 *hwcaps)
2401{
2402	struct spi_nor_flash_parameter *params = nor->params;
2403	unsigned int cap;
2404
2405	/* X-X-X modes are not supported yet, mask them all. */
2406	*hwcaps &= ~SNOR_HWCAPS_X_X_X;
2407
2408	/*
2409	 * If the reset line is broken, we do not want to enter a stateful
2410	 * mode.
2411	 */
2412	if (nor->flags & SNOR_F_BROKEN_RESET)
2413		*hwcaps &= ~(SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR);
2414
2415	for (cap = 0; cap < sizeof(*hwcaps) * BITS_PER_BYTE; cap++) {
2416		int rdidx, ppidx;
2417
2418		if (!(*hwcaps & BIT(cap)))
2419			continue;
2420
2421		rdidx = spi_nor_hwcaps_read2cmd(BIT(cap));
2422		if (rdidx >= 0 &&
2423		    spi_nor_spimem_check_readop(nor, &params->reads[rdidx]))
2424			*hwcaps &= ~BIT(cap);
2425
2426		ppidx = spi_nor_hwcaps_pp2cmd(BIT(cap));
2427		if (ppidx < 0)
2428			continue;
2429
2430		if (spi_nor_spimem_check_pp(nor,
2431					    &params->page_programs[ppidx]))
2432			*hwcaps &= ~BIT(cap);
2433	}
2434}
2435
2436/**
2437 * spi_nor_set_erase_type() - set a SPI NOR erase type
2438 * @erase:	pointer to a structure that describes a SPI NOR erase type
2439 * @size:	the size of the sector/block erased by the erase type
2440 * @opcode:	the SPI command op code to erase the sector/block
2441 */
2442void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
2443			    u8 opcode)
2444{
2445	erase->size = size;
2446	erase->opcode = opcode;
2447	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
2448	erase->size_shift = ffs(erase->size) - 1;
2449	erase->size_mask = (1 << erase->size_shift) - 1;
2450}
2451
2452/**
2453 * spi_nor_mask_erase_type() - mask out a SPI NOR erase type
2454 * @erase:	pointer to a structure that describes a SPI NOR erase type
2455 */
2456void spi_nor_mask_erase_type(struct spi_nor_erase_type *erase)
2457{
2458	erase->size = 0;
2459}
2460
2461/**
2462 * spi_nor_init_uniform_erase_map() - Initialize uniform erase map
2463 * @map:		the erase map of the SPI NOR
2464 * @erase_mask:		bitmask encoding erase types that can erase the entire
2465 *			flash memory
2466 * @flash_size:		the spi nor flash memory size
2467 */
2468void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
2469				    u8 erase_mask, u64 flash_size)
2470{
2471	/* Offset 0 with erase_mask and SNOR_LAST_REGION bit set */
2472	map->uniform_region.offset = (erase_mask & SNOR_ERASE_TYPE_MASK) |
2473				     SNOR_LAST_REGION;
2474	map->uniform_region.size = flash_size;
2475	map->regions = &map->uniform_region;
2476	map->uniform_erase_type = erase_mask;
2477}
2478
2479int spi_nor_post_bfpt_fixups(struct spi_nor *nor,
2480			     const struct sfdp_parameter_header *bfpt_header,
2481			     const struct sfdp_bfpt *bfpt)
2482{
2483	int ret;
2484
2485	if (nor->manufacturer && nor->manufacturer->fixups &&
2486	    nor->manufacturer->fixups->post_bfpt) {
2487		ret = nor->manufacturer->fixups->post_bfpt(nor, bfpt_header,
2488							   bfpt);
2489		if (ret)
2490			return ret;
2491	}
2492
2493	if (nor->info->fixups && nor->info->fixups->post_bfpt)
2494		return nor->info->fixups->post_bfpt(nor, bfpt_header, bfpt);
2495
2496	return 0;
2497}
2498
2499static int spi_nor_select_read(struct spi_nor *nor,
2500			       u32 shared_hwcaps)
2501{
2502	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_READ_MASK) - 1;
2503	const struct spi_nor_read_command *read;
2504
2505	if (best_match < 0)
2506		return -EINVAL;
2507
2508	cmd = spi_nor_hwcaps_read2cmd(BIT(best_match));
2509	if (cmd < 0)
2510		return -EINVAL;
2511
2512	read = &nor->params->reads[cmd];
2513	nor->read_opcode = read->opcode;
2514	nor->read_proto = read->proto;
2515
2516	/*
2517	 * In the SPI NOR framework, we don't need to make the difference
2518	 * between mode clock cycles and wait state clock cycles.
2519	 * Indeed, the value of the mode clock cycles is used by a QSPI
2520	 * flash memory to know whether it should enter or leave its 0-4-4
2521	 * (Continuous Read / XIP) mode.
2522	 * eXecution In Place is out of the scope of the mtd sub-system.
2523	 * Hence we choose to merge both mode and wait state clock cycles
2524	 * into the so called dummy clock cycles.
2525	 */
2526	nor->read_dummy = read->num_mode_clocks + read->num_wait_states;
2527	return 0;
2528}
2529
2530static int spi_nor_select_pp(struct spi_nor *nor,
2531			     u32 shared_hwcaps)
2532{
2533	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_PP_MASK) - 1;
2534	const struct spi_nor_pp_command *pp;
2535
2536	if (best_match < 0)
2537		return -EINVAL;
2538
2539	cmd = spi_nor_hwcaps_pp2cmd(BIT(best_match));
2540	if (cmd < 0)
2541		return -EINVAL;
2542
2543	pp = &nor->params->page_programs[cmd];
2544	nor->program_opcode = pp->opcode;
2545	nor->write_proto = pp->proto;
2546	return 0;
2547}
2548
2549/**
2550 * spi_nor_select_uniform_erase() - select optimum uniform erase type
2551 * @map:		the erase map of the SPI NOR
2552 *
2553 * Once the optimum uniform sector erase command is found, disable all the
2554 * other.
2555 *
2556 * Return: pointer to erase type on success, NULL otherwise.
2557 */
2558static const struct spi_nor_erase_type *
2559spi_nor_select_uniform_erase(struct spi_nor_erase_map *map)
2560{
2561	const struct spi_nor_erase_type *tested_erase, *erase = NULL;
2562	int i;
2563	u8 uniform_erase_type = map->uniform_erase_type;
2564
2565	/*
2566	 * Search for the biggest erase size, except for when compiled
2567	 * to use 4k erases.
2568	 */
2569	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2570		if (!(uniform_erase_type & BIT(i)))
2571			continue;
2572
2573		tested_erase = &map->erase_type[i];
2574
2575		/* Skip masked erase types. */
2576		if (!tested_erase->size)
2577			continue;
2578
2579		/*
2580		 * If the current erase size is the 4k one, stop here,
2581		 * we have found the right uniform Sector Erase command.
2582		 */
2583		if (IS_ENABLED(CONFIG_MTD_SPI_NOR_USE_4K_SECTORS) &&
2584		    tested_erase->size == SZ_4K) {
2585			erase = tested_erase;
2586			break;
2587		}
2588
2589		/*
2590		 * Otherwise, the current erase size is still a valid candidate.
2591		 * Select the biggest valid candidate.
2592		 */
2593		if (!erase && tested_erase->size)
2594			erase = tested_erase;
2595			/* keep iterating to find the wanted_size */
2596	}
2597
2598	if (!erase)
2599		return NULL;
2600
2601	/* Disable all other Sector Erase commands. */
2602	map->uniform_erase_type &= ~SNOR_ERASE_TYPE_MASK;
2603	map->uniform_erase_type |= BIT(erase - map->erase_type);
2604	return erase;
2605}
2606
2607static int spi_nor_select_erase(struct spi_nor *nor)
2608{
2609	struct spi_nor_erase_map *map = &nor->params->erase_map;
2610	const struct spi_nor_erase_type *erase = NULL;
2611	struct mtd_info *mtd = &nor->mtd;
2612	int i;
2613
2614	/*
2615	 * The previous implementation handling Sector Erase commands assumed
2616	 * that the SPI flash memory has an uniform layout then used only one
2617	 * of the supported erase sizes for all Sector Erase commands.
2618	 * So to be backward compatible, the new implementation also tries to
2619	 * manage the SPI flash memory as uniform with a single erase sector
2620	 * size, when possible.
2621	 */
2622	if (spi_nor_has_uniform_erase(nor)) {
2623		erase = spi_nor_select_uniform_erase(map);
2624		if (!erase)
2625			return -EINVAL;
2626		nor->erase_opcode = erase->opcode;
2627		mtd->erasesize = erase->size;
2628		return 0;
2629	}
2630
2631	/*
2632	 * For non-uniform SPI flash memory, set mtd->erasesize to the
2633	 * maximum erase sector size. No need to set nor->erase_opcode.
2634	 */
2635	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2636		if (map->erase_type[i].size) {
2637			erase = &map->erase_type[i];
2638			break;
2639		}
2640	}
2641
2642	if (!erase)
2643		return -EINVAL;
2644
2645	mtd->erasesize = erase->size;
2646	return 0;
2647}
2648
2649static int spi_nor_default_setup(struct spi_nor *nor,
2650				 const struct spi_nor_hwcaps *hwcaps)
2651{
2652	struct spi_nor_flash_parameter *params = nor->params;
2653	u32 ignored_mask, shared_mask;
2654	int err;
2655
2656	/*
2657	 * Keep only the hardware capabilities supported by both the SPI
2658	 * controller and the SPI flash memory.
2659	 */
2660	shared_mask = hwcaps->mask & params->hwcaps.mask;
2661
2662	if (nor->spimem) {
2663		/*
2664		 * When called from spi_nor_probe(), all caps are set and we
2665		 * need to discard some of them based on what the SPI
2666		 * controller actually supports (using spi_mem_supports_op()).
2667		 */
2668		spi_nor_spimem_adjust_hwcaps(nor, &shared_mask);
2669	} else {
2670		/*
2671		 * SPI n-n-n protocols are not supported when the SPI
2672		 * controller directly implements the spi_nor interface.
2673		 * Yet another reason to switch to spi-mem.
2674		 */
2675		ignored_mask = SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR;
2676		if (shared_mask & ignored_mask) {
2677			dev_dbg(nor->dev,
2678				"SPI n-n-n protocols are not supported.\n");
2679			shared_mask &= ~ignored_mask;
2680		}
2681	}
2682
2683	/* Select the (Fast) Read command. */
2684	err = spi_nor_select_read(nor, shared_mask);
2685	if (err) {
2686		dev_dbg(nor->dev,
2687			"can't select read settings supported by both the SPI controller and memory.\n");
2688		return err;
2689	}
2690
2691	/* Select the Page Program command. */
2692	err = spi_nor_select_pp(nor, shared_mask);
2693	if (err) {
2694		dev_dbg(nor->dev,
2695			"can't select write settings supported by both the SPI controller and memory.\n");
2696		return err;
2697	}
2698
2699	/* Select the Sector Erase command. */
2700	err = spi_nor_select_erase(nor);
2701	if (err) {
2702		dev_dbg(nor->dev,
2703			"can't select erase settings supported by both the SPI controller and memory.\n");
2704		return err;
2705	}
2706
2707	return 0;
2708}
2709
2710static int spi_nor_set_addr_nbytes(struct spi_nor *nor)
2711{
2712	if (nor->params->addr_nbytes) {
2713		nor->addr_nbytes = nor->params->addr_nbytes;
2714	} else if (nor->read_proto == SNOR_PROTO_8_8_8_DTR) {
2715		/*
2716		 * In 8D-8D-8D mode, one byte takes half a cycle to transfer. So
2717		 * in this protocol an odd addr_nbytes cannot be used because
2718		 * then the address phase would only span a cycle and a half.
2719		 * Half a cycle would be left over. We would then have to start
2720		 * the dummy phase in the middle of a cycle and so too the data
2721		 * phase, and we will end the transaction with half a cycle left
2722		 * over.
2723		 *
2724		 * Force all 8D-8D-8D flashes to use an addr_nbytes of 4 to
2725		 * avoid this situation.
2726		 */
2727		nor->addr_nbytes = 4;
2728	} else if (nor->info->addr_nbytes) {
2729		nor->addr_nbytes = nor->info->addr_nbytes;
2730	} else {
2731		nor->addr_nbytes = 3;
2732	}
2733
2734	if (nor->addr_nbytes == 3 && nor->params->size > 0x1000000) {
2735		/* enable 4-byte addressing if the device exceeds 16MiB */
2736		nor->addr_nbytes = 4;
2737	}
2738
2739	if (nor->addr_nbytes > SPI_NOR_MAX_ADDR_NBYTES) {
2740		dev_dbg(nor->dev, "The number of address bytes is too large: %u\n",
2741			nor->addr_nbytes);
2742		return -EINVAL;
2743	}
2744
2745	/* Set 4byte opcodes when possible. */
2746	if (nor->addr_nbytes == 4 && nor->flags & SNOR_F_4B_OPCODES &&
2747	    !(nor->flags & SNOR_F_HAS_4BAIT))
2748		spi_nor_set_4byte_opcodes(nor);
2749
2750	return 0;
2751}
2752
2753static int spi_nor_setup(struct spi_nor *nor,
2754			 const struct spi_nor_hwcaps *hwcaps)
2755{
2756	int ret;
2757
2758	if (nor->params->setup)
2759		ret = nor->params->setup(nor, hwcaps);
2760	else
2761		ret = spi_nor_default_setup(nor, hwcaps);
2762	if (ret)
2763		return ret;
2764
2765	return spi_nor_set_addr_nbytes(nor);
2766}
2767
2768/**
2769 * spi_nor_manufacturer_init_params() - Initialize the flash's parameters and
2770 * settings based on MFR register and ->default_init() hook.
2771 * @nor:	pointer to a 'struct spi_nor'.
2772 */
2773static void spi_nor_manufacturer_init_params(struct spi_nor *nor)
2774{
2775	if (nor->manufacturer && nor->manufacturer->fixups &&
2776	    nor->manufacturer->fixups->default_init)
2777		nor->manufacturer->fixups->default_init(nor);
2778
2779	if (nor->info->fixups && nor->info->fixups->default_init)
2780		nor->info->fixups->default_init(nor);
2781}
2782
2783/**
2784 * spi_nor_no_sfdp_init_params() - Initialize the flash's parameters and
2785 * settings based on nor->info->sfdp_flags. This method should be called only by
2786 * flashes that do not define SFDP tables. If the flash supports SFDP but the
2787 * information is wrong and the settings from this function can not be retrieved
2788 * by parsing SFDP, one should instead use the fixup hooks and update the wrong
2789 * bits.
2790 * @nor:	pointer to a 'struct spi_nor'.
2791 */
2792static void spi_nor_no_sfdp_init_params(struct spi_nor *nor)
2793{
2794	struct spi_nor_flash_parameter *params = nor->params;
2795	struct spi_nor_erase_map *map = &params->erase_map;
2796	const struct flash_info *info = nor->info;
2797	const u8 no_sfdp_flags = info->no_sfdp_flags;
2798	u8 i, erase_mask;
2799
2800	if (no_sfdp_flags & SPI_NOR_DUAL_READ) {
2801		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
2802		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_2],
2803					  0, 8, SPINOR_OP_READ_1_1_2,
2804					  SNOR_PROTO_1_1_2);
2805	}
2806
2807	if (no_sfdp_flags & SPI_NOR_QUAD_READ) {
2808		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
2809		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_4],
2810					  0, 8, SPINOR_OP_READ_1_1_4,
2811					  SNOR_PROTO_1_1_4);
2812	}
2813
2814	if (no_sfdp_flags & SPI_NOR_OCTAL_READ) {
2815		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
2816		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
2817					  0, 8, SPINOR_OP_READ_1_1_8,
2818					  SNOR_PROTO_1_1_8);
2819	}
2820
2821	if (no_sfdp_flags & SPI_NOR_OCTAL_DTR_READ) {
2822		params->hwcaps.mask |= SNOR_HWCAPS_READ_8_8_8_DTR;
2823		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_8_8_8_DTR],
2824					  0, 20, SPINOR_OP_READ_FAST,
2825					  SNOR_PROTO_8_8_8_DTR);
2826	}
2827
2828	if (no_sfdp_flags & SPI_NOR_OCTAL_DTR_PP) {
2829		params->hwcaps.mask |= SNOR_HWCAPS_PP_8_8_8_DTR;
2830		/*
2831		 * Since xSPI Page Program opcode is backward compatible with
2832		 * Legacy SPI, use Legacy SPI opcode there as well.
2833		 */
2834		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_8_8_8_DTR],
2835					SPINOR_OP_PP, SNOR_PROTO_8_8_8_DTR);
2836	}
2837
2838	/*
2839	 * Sector Erase settings. Sort Erase Types in ascending order, with the
2840	 * smallest erase size starting at BIT(0).
2841	 */
2842	erase_mask = 0;
2843	i = 0;
2844	if (no_sfdp_flags & SECT_4K) {
2845		erase_mask |= BIT(i);
2846		spi_nor_set_erase_type(&map->erase_type[i], 4096u,
2847				       SPINOR_OP_BE_4K);
2848		i++;
2849	}
2850	erase_mask |= BIT(i);
2851	spi_nor_set_erase_type(&map->erase_type[i],
2852			       info->sector_size ?: SPI_NOR_DEFAULT_SECTOR_SIZE,
2853			       SPINOR_OP_SE);
2854	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
2855}
2856
2857/**
2858 * spi_nor_init_flags() - Initialize NOR flags for settings that are not defined
2859 * in the JESD216 SFDP standard, thus can not be retrieved when parsing SFDP.
2860 * @nor:	pointer to a 'struct spi_nor'
2861 */
2862static void spi_nor_init_flags(struct spi_nor *nor)
2863{
2864	struct device_node *np = spi_nor_get_flash_node(nor);
2865	const u16 flags = nor->info->flags;
2866
2867	if (of_property_read_bool(np, "broken-flash-reset"))
2868		nor->flags |= SNOR_F_BROKEN_RESET;
2869
2870	if (of_property_read_bool(np, "no-wp"))
2871		nor->flags |= SNOR_F_NO_WP;
2872
2873	if (flags & SPI_NOR_SWP_IS_VOLATILE)
2874		nor->flags |= SNOR_F_SWP_IS_VOLATILE;
2875
2876	if (flags & SPI_NOR_HAS_LOCK)
2877		nor->flags |= SNOR_F_HAS_LOCK;
2878
2879	if (flags & SPI_NOR_HAS_TB) {
2880		nor->flags |= SNOR_F_HAS_SR_TB;
2881		if (flags & SPI_NOR_TB_SR_BIT6)
2882			nor->flags |= SNOR_F_HAS_SR_TB_BIT6;
2883	}
2884
2885	if (flags & SPI_NOR_4BIT_BP) {
2886		nor->flags |= SNOR_F_HAS_4BIT_BP;
2887		if (flags & SPI_NOR_BP3_SR_BIT6)
2888			nor->flags |= SNOR_F_HAS_SR_BP3_BIT6;
2889	}
2890
2891	if (flags & SPI_NOR_RWW && nor->params->n_banks > 1 &&
2892	    !nor->controller_ops)
2893		nor->flags |= SNOR_F_RWW;
2894}
2895
2896/**
2897 * spi_nor_init_fixup_flags() - Initialize NOR flags for settings that can not
2898 * be discovered by SFDP for this particular flash because the SFDP table that
2899 * indicates this support is not defined in the flash. In case the table for
2900 * this support is defined but has wrong values, one should instead use a
2901 * post_sfdp() hook to set the SNOR_F equivalent flag.
2902 * @nor:       pointer to a 'struct spi_nor'
2903 */
2904static void spi_nor_init_fixup_flags(struct spi_nor *nor)
2905{
2906	const u8 fixup_flags = nor->info->fixup_flags;
2907
2908	if (fixup_flags & SPI_NOR_4B_OPCODES)
2909		nor->flags |= SNOR_F_4B_OPCODES;
2910
2911	if (fixup_flags & SPI_NOR_IO_MODE_EN_VOLATILE)
2912		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;
2913}
2914
2915/**
2916 * spi_nor_late_init_params() - Late initialization of default flash parameters.
2917 * @nor:	pointer to a 'struct spi_nor'
2918 *
2919 * Used to initialize flash parameters that are not declared in the JESD216
2920 * SFDP standard, or where SFDP tables are not defined at all.
2921 * Will replace the spi_nor_manufacturer_init_params() method.
2922 */
2923static int spi_nor_late_init_params(struct spi_nor *nor)
2924{
2925	struct spi_nor_flash_parameter *params = nor->params;
2926	int ret;
2927
2928	if (nor->manufacturer && nor->manufacturer->fixups &&
2929	    nor->manufacturer->fixups->late_init) {
2930		ret = nor->manufacturer->fixups->late_init(nor);
2931		if (ret)
2932			return ret;
2933	}
2934
2935	/* Needed by some flashes late_init hooks. */
2936	spi_nor_init_flags(nor);
2937
2938	if (nor->info->fixups && nor->info->fixups->late_init) {
2939		ret = nor->info->fixups->late_init(nor);
2940		if (ret)
2941			return ret;
2942	}
2943
2944	if (!nor->params->die_erase_opcode)
2945		nor->params->die_erase_opcode = SPINOR_OP_CHIP_ERASE;
2946
2947	/* Default method kept for backward compatibility. */
2948	if (!params->set_4byte_addr_mode)
2949		params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_brwr;
2950
2951	spi_nor_init_fixup_flags(nor);
2952
2953	/*
2954	 * NOR protection support. When locking_ops are not provided, we pick
2955	 * the default ones.
2956	 */
2957	if (nor->flags & SNOR_F_HAS_LOCK && !nor->params->locking_ops)
2958		spi_nor_init_default_locking_ops(nor);
2959
2960	if (params->n_banks > 1)
2961		params->bank_size = div64_u64(params->size, params->n_banks);
2962
2963	return 0;
2964}
2965
2966/**
2967 * spi_nor_sfdp_init_params_deprecated() - Deprecated way of initializing flash
2968 * parameters and settings based on JESD216 SFDP standard.
2969 * @nor:	pointer to a 'struct spi_nor'.
2970 *
2971 * The method has a roll-back mechanism: in case the SFDP parsing fails, the
2972 * legacy flash parameters and settings will be restored.
2973 */
2974static void spi_nor_sfdp_init_params_deprecated(struct spi_nor *nor)
2975{
2976	struct spi_nor_flash_parameter sfdp_params;
2977
2978	memcpy(&sfdp_params, nor->params, sizeof(sfdp_params));
2979
2980	if (spi_nor_parse_sfdp(nor)) {
2981		memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
2982		nor->flags &= ~SNOR_F_4B_OPCODES;
2983	}
2984}
2985
2986/**
2987 * spi_nor_init_params_deprecated() - Deprecated way of initializing flash
2988 * parameters and settings.
2989 * @nor:	pointer to a 'struct spi_nor'.
2990 *
2991 * The method assumes that flash doesn't support SFDP so it initializes flash
2992 * parameters in spi_nor_no_sfdp_init_params() which later on can be overwritten
2993 * when parsing SFDP, if supported.
2994 */
2995static void spi_nor_init_params_deprecated(struct spi_nor *nor)
2996{
2997	spi_nor_no_sfdp_init_params(nor);
2998
2999	spi_nor_manufacturer_init_params(nor);
3000
3001	if (nor->info->no_sfdp_flags & (SPI_NOR_DUAL_READ |
3002					SPI_NOR_QUAD_READ |
3003					SPI_NOR_OCTAL_READ |
3004					SPI_NOR_OCTAL_DTR_READ))
3005		spi_nor_sfdp_init_params_deprecated(nor);
3006}
3007
3008/**
3009 * spi_nor_init_default_params() - Default initialization of flash parameters
3010 * and settings. Done for all flashes, regardless is they define SFDP tables
3011 * or not.
3012 * @nor:	pointer to a 'struct spi_nor'.
3013 */
3014static void spi_nor_init_default_params(struct spi_nor *nor)
3015{
3016	struct spi_nor_flash_parameter *params = nor->params;
3017	const struct flash_info *info = nor->info;
3018	struct device_node *np = spi_nor_get_flash_node(nor);
3019
3020	params->quad_enable = spi_nor_sr2_bit1_quad_enable;
3021	params->otp.org = info->otp;
3022
3023	/* Default to 16-bit Write Status (01h) Command */
3024	nor->flags |= SNOR_F_HAS_16BIT_SR;
3025
3026	/* Set SPI NOR sizes. */
3027	params->writesize = 1;
3028	params->size = info->size;
3029	params->bank_size = params->size;
3030	params->page_size = info->page_size ?: SPI_NOR_DEFAULT_PAGE_SIZE;
3031	params->n_banks = info->n_banks ?: SPI_NOR_DEFAULT_N_BANKS;
3032
3033	if (!(info->flags & SPI_NOR_NO_FR)) {
3034		/* Default to Fast Read for DT and non-DT platform devices. */
3035		params->hwcaps.mask |= SNOR_HWCAPS_READ_FAST;
3036
3037		/* Mask out Fast Read if not requested at DT instantiation. */
3038		if (np && !of_property_read_bool(np, "m25p,fast-read"))
3039			params->hwcaps.mask &= ~SNOR_HWCAPS_READ_FAST;
3040	}
3041
3042	/* (Fast) Read settings. */
3043	params->hwcaps.mask |= SNOR_HWCAPS_READ;
3044	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ],
3045				  0, 0, SPINOR_OP_READ,
3046				  SNOR_PROTO_1_1_1);
3047
3048	if (params->hwcaps.mask & SNOR_HWCAPS_READ_FAST)
3049		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_FAST],
3050					  0, 8, SPINOR_OP_READ_FAST,
3051					  SNOR_PROTO_1_1_1);
3052	/* Page Program settings. */
3053	params->hwcaps.mask |= SNOR_HWCAPS_PP;
3054	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP],
3055				SPINOR_OP_PP, SNOR_PROTO_1_1_1);
3056
3057	if (info->flags & SPI_NOR_QUAD_PP) {
3058		params->hwcaps.mask |= SNOR_HWCAPS_PP_1_1_4;
3059		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_1_1_4],
3060					SPINOR_OP_PP_1_1_4, SNOR_PROTO_1_1_4);
3061	}
3062}
3063
3064/**
3065 * spi_nor_init_params() - Initialize the flash's parameters and settings.
3066 * @nor:	pointer to a 'struct spi_nor'.
3067 *
3068 * The flash parameters and settings are initialized based on a sequence of
3069 * calls that are ordered by priority:
3070 *
3071 * 1/ Default flash parameters initialization. The initializations are done
3072 *    based on nor->info data:
3073 *		spi_nor_info_init_params()
3074 *
3075 * which can be overwritten by:
3076 * 2/ Manufacturer flash parameters initialization. The initializations are
3077 *    done based on MFR register, or when the decisions can not be done solely
3078 *    based on MFR, by using specific flash_info tweeks, ->default_init():
3079 *		spi_nor_manufacturer_init_params()
3080 *
3081 * which can be overwritten by:
3082 * 3/ SFDP flash parameters initialization. JESD216 SFDP is a standard and
3083 *    should be more accurate that the above.
3084 *		spi_nor_parse_sfdp() or spi_nor_no_sfdp_init_params()
3085 *
3086 *    Please note that there is a ->post_bfpt() fixup hook that can overwrite
3087 *    the flash parameters and settings immediately after parsing the Basic
3088 *    Flash Parameter Table.
3089 *    spi_nor_post_sfdp_fixups() is called after the SFDP tables are parsed.
3090 *    It is used to tweak various flash parameters when information provided
3091 *    by the SFDP tables are wrong.
3092 *
3093 * which can be overwritten by:
3094 * 4/ Late flash parameters initialization, used to initialize flash
3095 * parameters that are not declared in the JESD216 SFDP standard, or where SFDP
3096 * tables are not defined at all.
3097 *		spi_nor_late_init_params()
3098 *
3099 * Return: 0 on success, -errno otherwise.
3100 */
3101static int spi_nor_init_params(struct spi_nor *nor)
3102{
3103	int ret;
3104
3105	nor->params = devm_kzalloc(nor->dev, sizeof(*nor->params), GFP_KERNEL);
3106	if (!nor->params)
3107		return -ENOMEM;
3108
3109	spi_nor_init_default_params(nor);
3110
3111	if (spi_nor_needs_sfdp(nor)) {
3112		ret = spi_nor_parse_sfdp(nor);
3113		if (ret) {
3114			dev_err(nor->dev, "BFPT parsing failed. Please consider using SPI_NOR_SKIP_SFDP when declaring the flash\n");
3115			return ret;
3116		}
3117	} else if (nor->info->no_sfdp_flags & SPI_NOR_SKIP_SFDP) {
3118		spi_nor_no_sfdp_init_params(nor);
3119	} else {
3120		spi_nor_init_params_deprecated(nor);
3121	}
3122
3123	return spi_nor_late_init_params(nor);
3124}
3125
3126/** spi_nor_set_octal_dtr() - enable or disable Octal DTR I/O.
3127 * @nor:                 pointer to a 'struct spi_nor'
3128 * @enable:              whether to enable or disable Octal DTR
3129 *
3130 * Return: 0 on success, -errno otherwise.
3131 */
3132static int spi_nor_set_octal_dtr(struct spi_nor *nor, bool enable)
3133{
3134	int ret;
3135
3136	if (!nor->params->set_octal_dtr)
3137		return 0;
3138
3139	if (!(nor->read_proto == SNOR_PROTO_8_8_8_DTR &&
3140	      nor->write_proto == SNOR_PROTO_8_8_8_DTR))
3141		return 0;
3142
3143	if (!(nor->flags & SNOR_F_IO_MODE_EN_VOLATILE))
3144		return 0;
3145
3146	ret = nor->params->set_octal_dtr(nor, enable);
3147	if (ret)
3148		return ret;
3149
3150	if (enable)
3151		nor->reg_proto = SNOR_PROTO_8_8_8_DTR;
3152	else
3153		nor->reg_proto = SNOR_PROTO_1_1_1;
3154
3155	return 0;
3156}
3157
3158/**
3159 * spi_nor_quad_enable() - enable Quad I/O if needed.
3160 * @nor:                pointer to a 'struct spi_nor'
3161 *
3162 * Return: 0 on success, -errno otherwise.
3163 */
3164static int spi_nor_quad_enable(struct spi_nor *nor)
3165{
3166	if (!nor->params->quad_enable)
3167		return 0;
3168
3169	if (!(spi_nor_get_protocol_width(nor->read_proto) == 4 ||
3170	      spi_nor_get_protocol_width(nor->write_proto) == 4))
3171		return 0;
3172
3173	return nor->params->quad_enable(nor);
3174}
3175
3176/**
3177 * spi_nor_set_4byte_addr_mode() - Set address mode.
3178 * @nor:                pointer to a 'struct spi_nor'.
3179 * @enable:             enable/disable 4 byte address mode.
3180 *
3181 * Return: 0 on success, -errno otherwise.
3182 */
3183int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
3184{
3185	struct spi_nor_flash_parameter *params = nor->params;
3186	int ret;
3187
3188	if (enable) {
3189		/*
3190		 * If the RESET# pin isn't hooked up properly, or the system
3191		 * otherwise doesn't perform a reset command in the boot
3192		 * sequence, it's impossible to 100% protect against unexpected
3193		 * reboots (e.g., crashes). Warn the user (or hopefully, system
3194		 * designer) that this is bad.
3195		 */
3196		WARN_ONCE(nor->flags & SNOR_F_BROKEN_RESET,
3197			  "enabling reset hack; may not recover from unexpected reboots\n");
3198	}
3199
3200	ret = params->set_4byte_addr_mode(nor, enable);
3201	if (ret && ret != -EOPNOTSUPP)
3202		return ret;
3203
3204	if (enable) {
3205		params->addr_nbytes = 4;
3206		params->addr_mode_nbytes = 4;
3207	} else {
3208		params->addr_nbytes = 3;
3209		params->addr_mode_nbytes = 3;
3210	}
3211
3212	return 0;
3213}
3214
3215static int spi_nor_init(struct spi_nor *nor)
3216{
3217	int err;
3218
3219	err = spi_nor_set_octal_dtr(nor, true);
3220	if (err) {
3221		dev_dbg(nor->dev, "octal mode not supported\n");
3222		return err;
3223	}
3224
3225	err = spi_nor_quad_enable(nor);
3226	if (err) {
3227		dev_dbg(nor->dev, "quad mode not supported\n");
3228		return err;
3229	}
3230
3231	/*
3232	 * Some SPI NOR flashes are write protected by default after a power-on
3233	 * reset cycle, in order to avoid inadvertent writes during power-up.
3234	 * Backward compatibility imposes to unlock the entire flash memory
3235	 * array at power-up by default. Depending on the kernel configuration
3236	 * (1) do nothing, (2) always unlock the entire flash array or (3)
3237	 * unlock the entire flash array only when the software write
3238	 * protection bits are volatile. The latter is indicated by
3239	 * SNOR_F_SWP_IS_VOLATILE.
3240	 */
3241	if (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE) ||
3242	    (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE_ON_VOLATILE) &&
3243	     nor->flags & SNOR_F_SWP_IS_VOLATILE))
3244		spi_nor_try_unlock_all(nor);
3245
3246	if (nor->addr_nbytes == 4 &&
3247	    nor->read_proto != SNOR_PROTO_8_8_8_DTR &&
3248	    !(nor->flags & SNOR_F_4B_OPCODES))
3249		return spi_nor_set_4byte_addr_mode(nor, true);
3250
3251	return 0;
3252}
3253
3254/**
3255 * spi_nor_soft_reset() - Perform a software reset
3256 * @nor:	pointer to 'struct spi_nor'
3257 *
3258 * Performs a "Soft Reset and Enter Default Protocol Mode" sequence which resets
3259 * the device to its power-on-reset state. This is useful when the software has
3260 * made some changes to device (volatile) registers and needs to reset it before
3261 * shutting down, for example.
3262 *
3263 * Not every flash supports this sequence. The same set of opcodes might be used
3264 * for some other operation on a flash that does not support this. Support for
3265 * this sequence can be discovered via SFDP in the BFPT table.
3266 *
3267 * Return: 0 on success, -errno otherwise.
3268 */
3269static void spi_nor_soft_reset(struct spi_nor *nor)
3270{
3271	struct spi_mem_op op;
3272	int ret;
3273
3274	op = (struct spi_mem_op)SPINOR_SRSTEN_OP;
3275
3276	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3277
3278	ret = spi_mem_exec_op(nor->spimem, &op);
3279	if (ret) {
3280		if (ret != -EOPNOTSUPP)
3281			dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3282		return;
3283	}
3284
3285	op = (struct spi_mem_op)SPINOR_SRST_OP;
3286
3287	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3288
3289	ret = spi_mem_exec_op(nor->spimem, &op);
3290	if (ret) {
3291		dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3292		return;
3293	}
3294
3295	/*
3296	 * Software Reset is not instant, and the delay varies from flash to
3297	 * flash. Looking at a few flashes, most range somewhere below 100
3298	 * microseconds. So, sleep for a range of 200-400 us.
3299	 */
3300	usleep_range(SPI_NOR_SRST_SLEEP_MIN, SPI_NOR_SRST_SLEEP_MAX);
3301}
3302
3303/* mtd suspend handler */
3304static int spi_nor_suspend(struct mtd_info *mtd)
3305{
3306	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3307	int ret;
3308
3309	/* Disable octal DTR mode if we enabled it. */
3310	ret = spi_nor_set_octal_dtr(nor, false);
3311	if (ret)
3312		dev_err(nor->dev, "suspend() failed\n");
3313
3314	return ret;
3315}
3316
3317/* mtd resume handler */
3318static void spi_nor_resume(struct mtd_info *mtd)
3319{
3320	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3321	struct device *dev = nor->dev;
3322	int ret;
3323
3324	/* re-initialize the nor chip */
3325	ret = spi_nor_init(nor);
3326	if (ret)
3327		dev_err(dev, "resume() failed\n");
3328}
3329
3330static int spi_nor_get_device(struct mtd_info *mtd)
3331{
3332	struct mtd_info *master = mtd_get_master(mtd);
3333	struct spi_nor *nor = mtd_to_spi_nor(master);
3334	struct device *dev;
3335
3336	if (nor->spimem)
3337		dev = nor->spimem->spi->controller->dev.parent;
3338	else
3339		dev = nor->dev;
3340
3341	if (!try_module_get(dev->driver->owner))
3342		return -ENODEV;
3343
3344	return 0;
3345}
3346
3347static void spi_nor_put_device(struct mtd_info *mtd)
3348{
3349	struct mtd_info *master = mtd_get_master(mtd);
3350	struct spi_nor *nor = mtd_to_spi_nor(master);
3351	struct device *dev;
3352
3353	if (nor->spimem)
3354		dev = nor->spimem->spi->controller->dev.parent;
3355	else
3356		dev = nor->dev;
3357
3358	module_put(dev->driver->owner);
3359}
3360
3361static void spi_nor_restore(struct spi_nor *nor)
3362{
3363	int ret;
3364
3365	/* restore the addressing mode */
3366	if (nor->addr_nbytes == 4 && !(nor->flags & SNOR_F_4B_OPCODES) &&
3367	    nor->flags & SNOR_F_BROKEN_RESET) {
3368		ret = spi_nor_set_4byte_addr_mode(nor, false);
3369		if (ret)
3370			/*
3371			 * Do not stop the execution in the hope that the flash
3372			 * will default to the 3-byte address mode after the
3373			 * software reset.
3374			 */
3375			dev_err(nor->dev, "Failed to exit 4-byte address mode, err = %d\n", ret);
3376	}
3377
3378	if (nor->flags & SNOR_F_SOFT_RESET)
3379		spi_nor_soft_reset(nor);
3380}
3381
3382static const struct flash_info *spi_nor_match_name(struct spi_nor *nor,
3383						   const char *name)
3384{
3385	unsigned int i, j;
3386
3387	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
3388		for (j = 0; j < manufacturers[i]->nparts; j++) {
3389			if (!strcmp(name, manufacturers[i]->parts[j].name)) {
3390				nor->manufacturer = manufacturers[i];
3391				return &manufacturers[i]->parts[j];
3392			}
3393		}
3394	}
3395
3396	return NULL;
3397}
3398
3399static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
3400						       const char *name)
3401{
3402	const struct flash_info *info = NULL;
3403
3404	if (name)
3405		info = spi_nor_match_name(nor, name);
3406	/* Try to auto-detect if chip name wasn't specified or not found */
3407	if (!info)
3408		return spi_nor_detect(nor);
3409
3410	/*
3411	 * If caller has specified name of flash model that can normally be
3412	 * detected using JEDEC, let's verify it.
3413	 */
3414	if (name && info->id) {
3415		const struct flash_info *jinfo;
3416
3417		jinfo = spi_nor_detect(nor);
3418		if (IS_ERR(jinfo)) {
3419			return jinfo;
3420		} else if (jinfo != info) {
3421			/*
3422			 * JEDEC knows better, so overwrite platform ID. We
3423			 * can't trust partitions any longer, but we'll let
3424			 * mtd apply them anyway, since some partitions may be
3425			 * marked read-only, and we don't want to loose that
3426			 * information, even if it's not 100% accurate.
3427			 */
3428			dev_warn(nor->dev, "found %s, expected %s\n",
3429				 jinfo->name, info->name);
3430			info = jinfo;
3431		}
3432	}
3433
3434	return info;
3435}
3436
3437static void spi_nor_set_mtd_info(struct spi_nor *nor)
3438{
3439	struct mtd_info *mtd = &nor->mtd;
3440	struct device *dev = nor->dev;
3441
3442	spi_nor_set_mtd_locking_ops(nor);
3443	spi_nor_set_mtd_otp_ops(nor);
3444
3445	mtd->dev.parent = dev;
3446	if (!mtd->name)
3447		mtd->name = dev_name(dev);
3448	mtd->type = MTD_NORFLASH;
3449	mtd->flags = MTD_CAP_NORFLASH;
3450	/* Unset BIT_WRITEABLE to enable JFFS2 write buffer for ECC'd NOR */
3451	if (nor->flags & SNOR_F_ECC)
3452		mtd->flags &= ~MTD_BIT_WRITEABLE;
3453	if (nor->info->flags & SPI_NOR_NO_ERASE)
3454		mtd->flags |= MTD_NO_ERASE;
3455	else
3456		mtd->_erase = spi_nor_erase;
3457	mtd->writesize = nor->params->writesize;
3458	mtd->writebufsize = nor->params->page_size;
3459	mtd->size = nor->params->size;
3460	mtd->_read = spi_nor_read;
3461	/* Might be already set by some SST flashes. */
3462	if (!mtd->_write)
3463		mtd->_write = spi_nor_write;
3464	mtd->_suspend = spi_nor_suspend;
3465	mtd->_resume = spi_nor_resume;
3466	mtd->_get_device = spi_nor_get_device;
3467	mtd->_put_device = spi_nor_put_device;
3468}
3469
3470static int spi_nor_hw_reset(struct spi_nor *nor)
3471{
3472	struct gpio_desc *reset;
3473
3474	reset = devm_gpiod_get_optional(nor->dev, "reset", GPIOD_OUT_LOW);
3475	if (IS_ERR_OR_NULL(reset))
3476		return PTR_ERR_OR_ZERO(reset);
3477
3478	/*
3479	 * Experimental delay values by looking at different flash device
3480	 * vendors datasheets.
3481	 */
3482	usleep_range(1, 5);
3483	gpiod_set_value_cansleep(reset, 1);
3484	usleep_range(100, 150);
3485	gpiod_set_value_cansleep(reset, 0);
3486	usleep_range(1000, 1200);
3487
3488	return 0;
3489}
3490
3491int spi_nor_scan(struct spi_nor *nor, const char *name,
3492		 const struct spi_nor_hwcaps *hwcaps)
3493{
3494	const struct flash_info *info;
3495	struct device *dev = nor->dev;
3496	int ret;
3497
3498	ret = spi_nor_check(nor);
3499	if (ret)
3500		return ret;
3501
3502	/* Reset SPI protocol for all commands. */
3503	nor->reg_proto = SNOR_PROTO_1_1_1;
3504	nor->read_proto = SNOR_PROTO_1_1_1;
3505	nor->write_proto = SNOR_PROTO_1_1_1;
3506
3507	/*
3508	 * We need the bounce buffer early to read/write registers when going
3509	 * through the spi-mem layer (buffers have to be DMA-able).
3510	 * For spi-mem drivers, we'll reallocate a new buffer if
3511	 * nor->params->page_size turns out to be greater than PAGE_SIZE (which
3512	 * shouldn't happen before long since NOR pages are usually less
3513	 * than 1KB) after spi_nor_scan() returns.
3514	 */
3515	nor->bouncebuf_size = PAGE_SIZE;
3516	nor->bouncebuf = devm_kmalloc(dev, nor->bouncebuf_size,
3517				      GFP_KERNEL);
3518	if (!nor->bouncebuf)
3519		return -ENOMEM;
3520
3521	ret = spi_nor_hw_reset(nor);
3522	if (ret)
3523		return ret;
3524
3525	info = spi_nor_get_flash_info(nor, name);
3526	if (IS_ERR(info))
3527		return PTR_ERR(info);
3528
3529	nor->info = info;
3530
3531	mutex_init(&nor->lock);
3532
3533	/* Init flash parameters based on flash_info struct and SFDP */
3534	ret = spi_nor_init_params(nor);
3535	if (ret)
3536		return ret;
3537
3538	if (spi_nor_use_parallel_locking(nor))
3539		init_waitqueue_head(&nor->rww.wait);
3540
3541	/*
3542	 * Configure the SPI memory:
3543	 * - select op codes for (Fast) Read, Page Program and Sector Erase.
3544	 * - set the number of dummy cycles (mode cycles + wait states).
3545	 * - set the SPI protocols for register and memory accesses.
3546	 * - set the number of address bytes.
3547	 */
3548	ret = spi_nor_setup(nor, hwcaps);
3549	if (ret)
3550		return ret;
3551
3552	/* Send all the required SPI flash commands to initialize device */
3553	ret = spi_nor_init(nor);
3554	if (ret)
3555		return ret;
3556
3557	/* No mtd_info fields should be used up to this point. */
3558	spi_nor_set_mtd_info(nor);
3559
3560	dev_dbg(dev, "Manufacturer and device ID: %*phN\n",
3561		SPI_NOR_MAX_ID_LEN, nor->id);
3562
3563	return 0;
3564}
3565EXPORT_SYMBOL_GPL(spi_nor_scan);
3566
3567static int spi_nor_create_read_dirmap(struct spi_nor *nor)
3568{
3569	struct spi_mem_dirmap_info info = {
3570		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
3571				      SPI_MEM_OP_ADDR(nor->addr_nbytes, 0, 0),
3572				      SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
3573				      SPI_MEM_OP_DATA_IN(0, NULL, 0)),
3574		.offset = 0,
3575		.length = nor->params->size,
3576	};
3577	struct spi_mem_op *op = &info.op_tmpl;
3578
3579	spi_nor_spimem_setup_op(nor, op, nor->read_proto);
3580
3581	/* convert the dummy cycles to the number of bytes */
3582	op->dummy.nbytes = (nor->read_dummy * op->dummy.buswidth) / 8;
3583	if (spi_nor_protocol_is_dtr(nor->read_proto))
3584		op->dummy.nbytes *= 2;
3585
3586	/*
3587	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3588	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3589	 * do it explicitly.
3590	 */
3591	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
3592
3593	nor->dirmap.rdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3594						       &info);
3595	return PTR_ERR_OR_ZERO(nor->dirmap.rdesc);
3596}
3597
3598static int spi_nor_create_write_dirmap(struct spi_nor *nor)
3599{
3600	struct spi_mem_dirmap_info info = {
3601		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
3602				      SPI_MEM_OP_ADDR(nor->addr_nbytes, 0, 0),
3603				      SPI_MEM_OP_NO_DUMMY,
3604				      SPI_MEM_OP_DATA_OUT(0, NULL, 0)),
3605		.offset = 0,
3606		.length = nor->params->size,
3607	};
3608	struct spi_mem_op *op = &info.op_tmpl;
3609
3610	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
3611		op->addr.nbytes = 0;
3612
3613	spi_nor_spimem_setup_op(nor, op, nor->write_proto);
3614
3615	/*
3616	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3617	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3618	 * do it explicitly.
3619	 */
3620	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
3621
3622	nor->dirmap.wdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3623						       &info);
3624	return PTR_ERR_OR_ZERO(nor->dirmap.wdesc);
3625}
3626
3627static int spi_nor_probe(struct spi_mem *spimem)
3628{
3629	struct spi_device *spi = spimem->spi;
3630	struct flash_platform_data *data = dev_get_platdata(&spi->dev);
3631	struct spi_nor *nor;
3632	/*
3633	 * Enable all caps by default. The core will mask them after
3634	 * checking what's really supported using spi_mem_supports_op().
3635	 */
3636	const struct spi_nor_hwcaps hwcaps = { .mask = SNOR_HWCAPS_ALL };
3637	char *flash_name;
3638	int ret;
3639
3640	nor = devm_kzalloc(&spi->dev, sizeof(*nor), GFP_KERNEL);
3641	if (!nor)
3642		return -ENOMEM;
3643
3644	nor->spimem = spimem;
3645	nor->dev = &spi->dev;
3646	spi_nor_set_flash_node(nor, spi->dev.of_node);
3647
3648	spi_mem_set_drvdata(spimem, nor);
3649
3650	if (data && data->name)
3651		nor->mtd.name = data->name;
3652
3653	if (!nor->mtd.name)
3654		nor->mtd.name = spi_mem_get_name(spimem);
3655
3656	/*
3657	 * For some (historical?) reason many platforms provide two different
3658	 * names in flash_platform_data: "name" and "type". Quite often name is
3659	 * set to "m25p80" and then "type" provides a real chip name.
3660	 * If that's the case, respect "type" and ignore a "name".
3661	 */
3662	if (data && data->type)
3663		flash_name = data->type;
3664	else if (!strcmp(spi->modalias, "spi-nor"))
3665		flash_name = NULL; /* auto-detect */
3666	else
3667		flash_name = spi->modalias;
3668
3669	ret = spi_nor_scan(nor, flash_name, &hwcaps);
3670	if (ret)
3671		return ret;
3672
3673	spi_nor_debugfs_register(nor);
3674
3675	/*
3676	 * None of the existing parts have > 512B pages, but let's play safe
3677	 * and add this logic so that if anyone ever adds support for such
3678	 * a NOR we don't end up with buffer overflows.
3679	 */
3680	if (nor->params->page_size > PAGE_SIZE) {
3681		nor->bouncebuf_size = nor->params->page_size;
3682		devm_kfree(nor->dev, nor->bouncebuf);
3683		nor->bouncebuf = devm_kmalloc(nor->dev,
3684					      nor->bouncebuf_size,
3685					      GFP_KERNEL);
3686		if (!nor->bouncebuf)
3687			return -ENOMEM;
3688	}
3689
3690	ret = spi_nor_create_read_dirmap(nor);
3691	if (ret)
3692		return ret;
3693
3694	ret = spi_nor_create_write_dirmap(nor);
3695	if (ret)
3696		return ret;
3697
3698	return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
3699				   data ? data->nr_parts : 0);
3700}
3701
3702static int spi_nor_remove(struct spi_mem *spimem)
3703{
3704	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3705
3706	spi_nor_restore(nor);
3707
3708	/* Clean up MTD stuff. */
3709	return mtd_device_unregister(&nor->mtd);
3710}
3711
3712static void spi_nor_shutdown(struct spi_mem *spimem)
3713{
3714	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3715
3716	spi_nor_restore(nor);
3717}
3718
3719/*
3720 * Do NOT add to this array without reading the following:
3721 *
3722 * Historically, many flash devices are bound to this driver by their name. But
3723 * since most of these flash are compatible to some extent, and their
3724 * differences can often be differentiated by the JEDEC read-ID command, we
3725 * encourage new users to add support to the spi-nor library, and simply bind
3726 * against a generic string here (e.g., "jedec,spi-nor").
3727 *
3728 * Many flash names are kept here in this list to keep them available
3729 * as module aliases for existing platforms.
3730 */
3731static const struct spi_device_id spi_nor_dev_ids[] = {
3732	/*
3733	 * Allow non-DT platform devices to bind to the "spi-nor" modalias, and
3734	 * hack around the fact that the SPI core does not provide uevent
3735	 * matching for .of_match_table
3736	 */
3737	{"spi-nor"},
3738
3739	/*
3740	 * Entries not used in DTs that should be safe to drop after replacing
3741	 * them with "spi-nor" in platform data.
3742	 */
3743	{"s25sl064a"},	{"w25x16"},	{"m25p10"},	{"m25px64"},
3744
3745	/*
3746	 * Entries that were used in DTs without "jedec,spi-nor" fallback and
3747	 * should be kept for backward compatibility.
3748	 */
3749	{"at25df321a"},	{"at25df641"},	{"at26df081a"},
3750	{"mx25l4005a"},	{"mx25l1606e"},	{"mx25l6405d"},	{"mx25l12805d"},
3751	{"mx25l25635e"},{"mx66l51235l"},
3752	{"n25q064"},	{"n25q128a11"},	{"n25q128a13"},	{"n25q512a"},
3753	{"s25fl256s1"},	{"s25fl512s"},	{"s25sl12801"},	{"s25fl008k"},
3754	{"s25fl064k"},
3755	{"sst25vf040b"},{"sst25vf016b"},{"sst25vf032b"},{"sst25wf040"},
3756	{"m25p40"},	{"m25p80"},	{"m25p16"},	{"m25p32"},
3757	{"m25p64"},	{"m25p128"},
3758	{"w25x80"},	{"w25x32"},	{"w25q32"},	{"w25q32dw"},
3759	{"w25q80bl"},	{"w25q128"},	{"w25q256"},
3760
3761	/* Flashes that can't be detected using JEDEC */
3762	{"m25p05-nonjedec"},	{"m25p10-nonjedec"},	{"m25p20-nonjedec"},
3763	{"m25p40-nonjedec"},	{"m25p80-nonjedec"},	{"m25p16-nonjedec"},
3764	{"m25p32-nonjedec"},	{"m25p64-nonjedec"},	{"m25p128-nonjedec"},
3765
3766	/* Everspin MRAMs (non-JEDEC) */
3767	{ "mr25h128" }, /* 128 Kib, 40 MHz */
3768	{ "mr25h256" }, /* 256 Kib, 40 MHz */
3769	{ "mr25h10" },  /*   1 Mib, 40 MHz */
3770	{ "mr25h40" },  /*   4 Mib, 40 MHz */
3771
3772	{ },
3773};
3774MODULE_DEVICE_TABLE(spi, spi_nor_dev_ids);
3775
3776static const struct of_device_id spi_nor_of_table[] = {
3777	/*
3778	 * Generic compatibility for SPI NOR that can be identified by the
3779	 * JEDEC READ ID opcode (0x9F). Use this, if possible.
3780	 */
3781	{ .compatible = "jedec,spi-nor" },
3782	{ /* sentinel */ },
3783};
3784MODULE_DEVICE_TABLE(of, spi_nor_of_table);
3785
3786/*
3787 * REVISIT: many of these chips have deep power-down modes, which
3788 * should clearly be entered on suspend() to minimize power use.
3789 * And also when they're otherwise idle...
3790 */
3791static struct spi_mem_driver spi_nor_driver = {
3792	.spidrv = {
3793		.driver = {
3794			.name = "spi-nor",
3795			.of_match_table = spi_nor_of_table,
3796			.dev_groups = spi_nor_sysfs_groups,
3797		},
3798		.id_table = spi_nor_dev_ids,
3799	},
3800	.probe = spi_nor_probe,
3801	.remove = spi_nor_remove,
3802	.shutdown = spi_nor_shutdown,
3803};
3804
3805static int __init spi_nor_module_init(void)
3806{
3807	return spi_mem_driver_register(&spi_nor_driver);
3808}
3809module_init(spi_nor_module_init);
3810
3811static void __exit spi_nor_module_exit(void)
3812{
3813	spi_mem_driver_unregister(&spi_nor_driver);
3814	spi_nor_debugfs_shutdown();
3815}
3816module_exit(spi_nor_module_exit);
3817
3818MODULE_LICENSE("GPL v2");
3819MODULE_AUTHOR("Huang Shijie <shijie8@gmail.com>");
3820MODULE_AUTHOR("Mike Lavender");
3821MODULE_DESCRIPTION("framework for SPI NOR");