xref: /linux/drivers/mtd/spi-nor/core.c (revision 49420dfdedd676befaa999b165a76d8d7eec4fab)
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/cleanup.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/errno.h>
15 #include <linux/math64.h>
16 #include <linux/module.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/mtd/spi-nor.h>
19 #include <linux/mutex.h>
20 #include <linux/of.h>
21 #include <linux/regulator/consumer.h>
22 #include <linux/sched/task_stack.h>
23 #include <linux/sizes.h>
24 #include <linux/slab.h>
25 #include <linux/spi/flash.h>
26 
27 #include "core.h"
28 
29 /* Define max times to check status register before we give up. */
30 
31 /*
32  * For everything but full-chip erase; probably could be much smaller, but kept
33  * around for safety for now
34  */
35 #define DEFAULT_READY_WAIT_JIFFIES		(40UL * HZ)
36 
37 /*
38  * For full-chip erase, calibrated to a 2MB flash (M25P16); should be scaled up
39  * for larger flash
40  */
41 #define CHIP_ERASE_2MB_READY_WAIT_JIFFIES	(40UL * HZ)
42 
43 #define SPI_NOR_MAX_ADDR_NBYTES	4
44 
45 #define SPI_NOR_SRST_SLEEP_MIN 200
46 #define SPI_NOR_SRST_SLEEP_MAX 400
47 
48 /**
49  * spi_nor_get_cmd_ext() - Get the command opcode extension based on the
50  *			   extension type.
51  * @nor:		pointer to a 'struct spi_nor'
52  * @op:			pointer to the 'struct spi_mem_op' whose properties
53  *			need to be initialized.
54  *
55  * Right now, only "repeat" and "invert" are supported.
56  *
57  * Return: The opcode extension.
58  */
59 static u8 spi_nor_get_cmd_ext(const struct spi_nor *nor,
60 			      const struct spi_mem_op *op)
61 {
62 	switch (nor->cmd_ext_type) {
63 	case SPI_NOR_EXT_INVERT:
64 		return ~op->cmd.opcode;
65 
66 	case SPI_NOR_EXT_REPEAT:
67 		return op->cmd.opcode;
68 
69 	default:
70 		dev_err(nor->dev, "Unknown command extension type\n");
71 		return 0;
72 	}
73 }
74 
75 /**
76  * spi_nor_spimem_setup_op() - Set up common properties of a spi-mem op.
77  * @nor:		pointer to a 'struct spi_nor'
78  * @op:			pointer to the 'struct spi_mem_op' whose properties
79  *			need to be initialized.
80  * @proto:		the protocol from which the properties need to be set.
81  */
82 void spi_nor_spimem_setup_op(const struct spi_nor *nor,
83 			     struct spi_mem_op *op,
84 			     const enum spi_nor_protocol proto)
85 {
86 	u8 ext;
87 
88 	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(proto);
89 
90 	if (op->addr.nbytes)
91 		op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
92 
93 	if (op->dummy.nbytes)
94 		op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
95 
96 	if (op->data.nbytes)
97 		op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
98 
99 	if (spi_nor_protocol_is_dtr(proto)) {
100 		/*
101 		 * SPIMEM supports mixed DTR modes, but right now we can only
102 		 * have all phases either DTR or STR. IOW, SPIMEM can have
103 		 * something like 4S-4D-4D, but SPI NOR can't. So, set all 4
104 		 * phases to either DTR or STR.
105 		 */
106 		op->cmd.dtr = true;
107 		op->addr.dtr = true;
108 		op->dummy.dtr = true;
109 		op->data.dtr = true;
110 
111 		/* 2 bytes per clock cycle in DTR mode. */
112 		op->dummy.nbytes *= 2;
113 
114 		ext = spi_nor_get_cmd_ext(nor, op);
115 		op->cmd.opcode = (op->cmd.opcode << 8) | ext;
116 		op->cmd.nbytes = 2;
117 	}
118 
119 	if (proto == SNOR_PROTO_8_8_8_DTR && nor->flags & SNOR_F_SWAP16)
120 		op->data.swap16 = true;
121 }
122 
123 /**
124  * spi_nor_spimem_bounce() - check if a bounce buffer is needed for the data
125  *                           transfer
126  * @nor:        pointer to 'struct spi_nor'
127  * @op:         pointer to 'struct spi_mem_op' template for transfer
128  *
129  * If we have to use the bounce buffer, the data field in @op will be updated.
130  *
131  * Return: true if the bounce buffer is needed, false if not
132  */
133 static bool spi_nor_spimem_bounce(struct spi_nor *nor, struct spi_mem_op *op)
134 {
135 	/* op->data.buf.in occupies the same memory as op->data.buf.out */
136 	if (object_is_on_stack(op->data.buf.in) ||
137 	    !virt_addr_valid(op->data.buf.in)) {
138 		if (op->data.nbytes > nor->bouncebuf_size)
139 			op->data.nbytes = nor->bouncebuf_size;
140 		op->data.buf.in = nor->bouncebuf;
141 		return true;
142 	}
143 
144 	return false;
145 }
146 
147 /**
148  * spi_nor_spimem_exec_op() - execute a memory operation
149  * @nor:        pointer to 'struct spi_nor'
150  * @op:         pointer to 'struct spi_mem_op' template for transfer
151  *
152  * Return: 0 on success, -error otherwise.
153  */
154 static int spi_nor_spimem_exec_op(struct spi_nor *nor, struct spi_mem_op *op)
155 {
156 	int error;
157 
158 	error = spi_mem_adjust_op_size(nor->spimem, op);
159 	if (error)
160 		return error;
161 
162 	return spi_mem_exec_op(nor->spimem, op);
163 }
164 
165 int spi_nor_controller_ops_read_reg(struct spi_nor *nor, u8 opcode,
166 				    u8 *buf, size_t len)
167 {
168 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
169 		return -EOPNOTSUPP;
170 
171 	return nor->controller_ops->read_reg(nor, opcode, buf, len);
172 }
173 
174 int spi_nor_controller_ops_write_reg(struct spi_nor *nor, u8 opcode,
175 				     const u8 *buf, size_t len)
176 {
177 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
178 		return -EOPNOTSUPP;
179 
180 	return nor->controller_ops->write_reg(nor, opcode, buf, len);
181 }
182 
183 static int spi_nor_controller_ops_erase(struct spi_nor *nor, loff_t offs)
184 {
185 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
186 		return -EOPNOTSUPP;
187 
188 	return nor->controller_ops->erase(nor, offs);
189 }
190 
191 /**
192  * spi_nor_spimem_read_data() - read data from flash's memory region via
193  *                              spi-mem
194  * @nor:        pointer to 'struct spi_nor'
195  * @from:       offset to read from
196  * @len:        number of bytes to read
197  * @buf:        pointer to dst buffer
198  *
199  * Return: number of bytes read successfully, -errno otherwise
200  */
201 static ssize_t spi_nor_spimem_read_data(struct spi_nor *nor, loff_t from,
202 					size_t len, u8 *buf)
203 {
204 	struct spi_mem_op op =
205 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
206 			   SPI_MEM_OP_ADDR(nor->addr_nbytes, from, 0),
207 			   SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
208 			   SPI_MEM_OP_DATA_IN(len, buf, 0));
209 	bool usebouncebuf;
210 	ssize_t nbytes;
211 	int error;
212 
213 	spi_nor_spimem_setup_op(nor, &op, nor->read_proto);
214 
215 	/* convert the dummy cycles to the number of bytes */
216 	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
217 	if (spi_nor_protocol_is_dtr(nor->read_proto))
218 		op.dummy.nbytes *= 2;
219 
220 	usebouncebuf = spi_nor_spimem_bounce(nor, &op);
221 
222 	if (nor->dirmap.rdesc) {
223 		nbytes = spi_mem_dirmap_read(nor->dirmap.rdesc, op.addr.val,
224 					     op.data.nbytes, op.data.buf.in);
225 	} else {
226 		error = spi_nor_spimem_exec_op(nor, &op);
227 		if (error)
228 			return error;
229 		nbytes = op.data.nbytes;
230 	}
231 
232 	if (usebouncebuf && nbytes > 0)
233 		memcpy(buf, op.data.buf.in, nbytes);
234 
235 	return nbytes;
236 }
237 
238 /**
239  * spi_nor_read_data() - read data from flash memory
240  * @nor:        pointer to 'struct spi_nor'
241  * @from:       offset to read from
242  * @len:        number of bytes to read
243  * @buf:        pointer to dst buffer
244  *
245  * Return: number of bytes read successfully, -errno otherwise
246  */
247 ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len, u8 *buf)
248 {
249 	if (nor->spimem)
250 		return spi_nor_spimem_read_data(nor, from, len, buf);
251 
252 	return nor->controller_ops->read(nor, from, len, buf);
253 }
254 
255 /**
256  * spi_nor_spimem_write_data() - write data to flash memory via
257  *                               spi-mem
258  * @nor:        pointer to 'struct spi_nor'
259  * @to:         offset to write to
260  * @len:        number of bytes to write
261  * @buf:        pointer to src buffer
262  *
263  * Return: number of bytes written successfully, -errno otherwise
264  */
265 static ssize_t spi_nor_spimem_write_data(struct spi_nor *nor, loff_t to,
266 					 size_t len, const u8 *buf)
267 {
268 	struct spi_mem_op op =
269 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
270 			   SPI_MEM_OP_ADDR(nor->addr_nbytes, to, 0),
271 			   SPI_MEM_OP_NO_DUMMY,
272 			   SPI_MEM_OP_DATA_OUT(len, buf, 0));
273 	ssize_t nbytes;
274 	int error;
275 
276 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
277 		op.addr.nbytes = 0;
278 
279 	spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
280 
281 	if (spi_nor_spimem_bounce(nor, &op))
282 		memcpy(nor->bouncebuf, buf, op.data.nbytes);
283 
284 	if (nor->dirmap.wdesc) {
285 		nbytes = spi_mem_dirmap_write(nor->dirmap.wdesc, op.addr.val,
286 					      op.data.nbytes, op.data.buf.out);
287 	} else {
288 		error = spi_nor_spimem_exec_op(nor, &op);
289 		if (error)
290 			return error;
291 		nbytes = op.data.nbytes;
292 	}
293 
294 	return nbytes;
295 }
296 
297 /**
298  * spi_nor_write_data() - write data to flash memory
299  * @nor:        pointer to 'struct spi_nor'
300  * @to:         offset to write to
301  * @len:        number of bytes to write
302  * @buf:        pointer to src buffer
303  *
304  * Return: number of bytes written successfully, -errno otherwise
305  */
306 ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
307 			   const u8 *buf)
308 {
309 	if (nor->spimem)
310 		return spi_nor_spimem_write_data(nor, to, len, buf);
311 
312 	return nor->controller_ops->write(nor, to, len, buf);
313 }
314 
315 /**
316  * spi_nor_read_any_reg() - read any register from flash memory, nonvolatile or
317  * volatile.
318  * @nor:        pointer to 'struct spi_nor'.
319  * @op:		SPI memory operation. op->data.buf must be DMA-able.
320  * @proto:	SPI protocol to use for the register operation.
321  *
322  * Return: zero on success, -errno otherwise
323  */
324 int spi_nor_read_any_reg(struct spi_nor *nor, struct spi_mem_op *op,
325 			 enum spi_nor_protocol proto)
326 {
327 	if (!nor->spimem)
328 		return -EOPNOTSUPP;
329 
330 	spi_nor_spimem_setup_op(nor, op, proto);
331 	return spi_nor_spimem_exec_op(nor, op);
332 }
333 
334 /**
335  * spi_nor_write_any_volatile_reg() - write any volatile register to flash
336  * memory.
337  * @nor:        pointer to 'struct spi_nor'
338  * @op:		SPI memory operation. op->data.buf must be DMA-able.
339  * @proto:	SPI protocol to use for the register operation.
340  *
341  * Writing volatile registers are instant according to some manufacturers
342  * (Cypress, Micron) and do not need any status polling.
343  *
344  * Return: zero on success, -errno otherwise
345  */
346 int spi_nor_write_any_volatile_reg(struct spi_nor *nor, struct spi_mem_op *op,
347 				   enum spi_nor_protocol proto)
348 {
349 	int ret;
350 
351 	if (!nor->spimem)
352 		return -EOPNOTSUPP;
353 
354 	ret = spi_nor_write_enable(nor);
355 	if (ret)
356 		return ret;
357 	spi_nor_spimem_setup_op(nor, op, proto);
358 	return spi_nor_spimem_exec_op(nor, op);
359 }
360 
361 /**
362  * spi_nor_write_enable() - Set write enable latch with Write Enable command.
363  * @nor:	pointer to 'struct spi_nor'.
364  *
365  * Return: 0 on success, -errno otherwise.
366  */
367 int spi_nor_write_enable(struct spi_nor *nor)
368 {
369 	int ret;
370 
371 	if (nor->spimem) {
372 		struct spi_mem_op op = SPI_NOR_WREN_OP;
373 
374 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
375 
376 		ret = spi_mem_exec_op(nor->spimem, &op);
377 	} else {
378 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WREN,
379 						       NULL, 0);
380 	}
381 
382 	if (ret)
383 		dev_dbg(nor->dev, "error %d on Write Enable\n", ret);
384 
385 	return ret;
386 }
387 
388 /**
389  * spi_nor_write_disable() - Send Write Disable instruction to the chip.
390  * @nor:	pointer to 'struct spi_nor'.
391  *
392  * Return: 0 on success, -errno otherwise.
393  */
394 int spi_nor_write_disable(struct spi_nor *nor)
395 {
396 	int ret;
397 
398 	if (nor->spimem) {
399 		struct spi_mem_op op = SPI_NOR_WRDI_OP;
400 
401 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
402 
403 		ret = spi_mem_exec_op(nor->spimem, &op);
404 	} else {
405 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRDI,
406 						       NULL, 0);
407 	}
408 
409 	if (ret)
410 		dev_dbg(nor->dev, "error %d on Write Disable\n", ret);
411 
412 	return ret;
413 }
414 
415 /**
416  * spi_nor_read_id() - Read the JEDEC ID.
417  * @nor:	pointer to 'struct spi_nor'.
418  * @naddr:	number of address bytes to send. Can be zero if the operation
419  *		does not need to send an address.
420  * @ndummy:	number of dummy bytes to send after an opcode or address. Can
421  *		be zero if the operation does not require dummy bytes.
422  * @id:		pointer to a DMA-able buffer where the value of the JEDEC ID
423  *		will be written.
424  * @proto:	the SPI protocol for register operation.
425  *
426  * Return: 0 on success, -errno otherwise.
427  */
428 int spi_nor_read_id(struct spi_nor *nor, u8 naddr, u8 ndummy, u8 *id,
429 		    enum spi_nor_protocol proto)
430 {
431 	int ret;
432 
433 	if (nor->spimem) {
434 		struct spi_mem_op op =
435 			SPI_NOR_READID_OP(naddr, ndummy, id, SPI_NOR_MAX_ID_LEN);
436 
437 		spi_nor_spimem_setup_op(nor, &op, proto);
438 		ret = spi_mem_exec_op(nor->spimem, &op);
439 	} else {
440 		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDID, id,
441 						    SPI_NOR_MAX_ID_LEN);
442 	}
443 	return ret;
444 }
445 
446 /**
447  * spi_nor_read_sr() - Read the Status Register.
448  * @nor:	pointer to 'struct spi_nor'.
449  * @sr:		pointer to a DMA-able buffer where the value of the
450  *              Status Register will be written. Should be at least 2 bytes.
451  *
452  * Return: 0 on success, -errno otherwise.
453  */
454 int spi_nor_read_sr(struct spi_nor *nor, u8 *sr)
455 {
456 	int ret;
457 
458 	if (nor->spimem) {
459 		struct spi_mem_op op = SPI_NOR_RDSR_OP(sr);
460 
461 		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
462 			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
463 			op.dummy.nbytes = nor->params->rdsr_dummy;
464 			/*
465 			 * We don't want to read only one byte in DTR mode. So,
466 			 * read 2 and then discard the second byte.
467 			 */
468 			op.data.nbytes = 2;
469 		}
470 
471 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
472 
473 		ret = spi_mem_exec_op(nor->spimem, &op);
474 	} else {
475 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR, sr,
476 						      1);
477 	}
478 
479 	if (ret)
480 		dev_dbg(nor->dev, "error %d reading SR\n", ret);
481 
482 	return ret;
483 }
484 
485 /**
486  * spi_nor_read_cr() - Read the Configuration Register using the
487  * SPINOR_OP_RDCR (35h) command.
488  * @nor:	pointer to 'struct spi_nor'
489  * @cr:		pointer to a DMA-able buffer where the value of the
490  *              Configuration Register will be written.
491  *
492  * Return: 0 on success, -errno otherwise.
493  */
494 int spi_nor_read_cr(struct spi_nor *nor, u8 *cr)
495 {
496 	int ret;
497 
498 	if (nor->spimem) {
499 		struct spi_mem_op op = SPI_NOR_RDCR_OP(cr);
500 
501 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
502 
503 		ret = spi_mem_exec_op(nor->spimem, &op);
504 	} else {
505 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDCR, cr,
506 						      1);
507 	}
508 
509 	if (ret)
510 		dev_dbg(nor->dev, "error %d reading CR\n", ret);
511 
512 	return ret;
513 }
514 
515 /**
516  * spi_nor_set_4byte_addr_mode_en4b_ex4b() - Enter/Exit 4-byte address mode
517  *			using SPINOR_OP_EN4B/SPINOR_OP_EX4B. Typically used by
518  *			Winbond and Macronix.
519  * @nor:	pointer to 'struct spi_nor'.
520  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
521  *		address mode.
522  *
523  * Return: 0 on success, -errno otherwise.
524  */
525 int spi_nor_set_4byte_addr_mode_en4b_ex4b(struct spi_nor *nor, bool enable)
526 {
527 	int ret;
528 
529 	if (nor->spimem) {
530 		struct spi_mem_op op = SPI_NOR_EN4B_EX4B_OP(enable);
531 
532 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
533 
534 		ret = spi_mem_exec_op(nor->spimem, &op);
535 	} else {
536 		ret = spi_nor_controller_ops_write_reg(nor,
537 						       enable ? SPINOR_OP_EN4B :
538 								SPINOR_OP_EX4B,
539 						       NULL, 0);
540 	}
541 
542 	if (ret)
543 		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
544 
545 	return ret;
546 }
547 
548 /**
549  * spi_nor_set_4byte_addr_mode_wren_en4b_ex4b() - Set 4-byte address mode using
550  * SPINOR_OP_WREN followed by SPINOR_OP_EN4B or SPINOR_OP_EX4B. Typically used
551  * by ST and Micron flashes.
552  * @nor:	pointer to 'struct spi_nor'.
553  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
554  *		address mode.
555  *
556  * Return: 0 on success, -errno otherwise.
557  */
558 int spi_nor_set_4byte_addr_mode_wren_en4b_ex4b(struct spi_nor *nor, bool enable)
559 {
560 	int ret;
561 
562 	ret = spi_nor_write_enable(nor);
563 	if (ret)
564 		return ret;
565 
566 	ret = spi_nor_set_4byte_addr_mode_en4b_ex4b(nor, enable);
567 	if (ret)
568 		return ret;
569 
570 	return spi_nor_write_disable(nor);
571 }
572 
573 /**
574  * spi_nor_set_4byte_addr_mode_brwr() - Set 4-byte address mode using
575  *			SPINOR_OP_BRWR. Typically used by Spansion flashes.
576  * @nor:	pointer to 'struct spi_nor'.
577  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
578  *		address mode.
579  *
580  * 8-bit volatile bank register used to define A[30:A24] bits. MSB (bit[7]) is
581  * used to enable/disable 4-byte address mode. When MSB is set to ‘1’, 4-byte
582  * address mode is active and A[30:24] bits are don’t care. Write instruction is
583  * SPINOR_OP_BRWR(17h) with 1 byte of data.
584  *
585  * Return: 0 on success, -errno otherwise.
586  */
587 int spi_nor_set_4byte_addr_mode_brwr(struct spi_nor *nor, bool enable)
588 {
589 	int ret;
590 
591 	nor->bouncebuf[0] = enable << 7;
592 
593 	if (nor->spimem) {
594 		struct spi_mem_op op = SPI_NOR_BRWR_OP(nor->bouncebuf);
595 
596 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
597 
598 		ret = spi_mem_exec_op(nor->spimem, &op);
599 	} else {
600 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_BRWR,
601 						       nor->bouncebuf, 1);
602 	}
603 
604 	if (ret)
605 		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
606 
607 	return ret;
608 }
609 
610 /**
611  * spi_nor_sr_ready() - Query the Status Register to see if the flash is ready
612  * for new commands.
613  * @nor:	pointer to 'struct spi_nor'.
614  *
615  * Return: 1 if ready, 0 if not ready, -errno on errors.
616  */
617 int spi_nor_sr_ready(struct spi_nor *nor)
618 {
619 	int ret;
620 
621 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
622 	if (ret)
623 		return ret;
624 
625 	return !(nor->bouncebuf[0] & SR_WIP);
626 }
627 
628 /**
629  * spi_nor_use_parallel_locking() - Checks if RWW locking scheme shall be used
630  * @nor:	pointer to 'struct spi_nor'.
631  *
632  * Return: true if parallel locking is enabled, false otherwise.
633  */
634 static bool spi_nor_use_parallel_locking(struct spi_nor *nor)
635 {
636 	return nor->flags & SNOR_F_RWW;
637 }
638 
639 /* Locking helpers for status read operations */
640 static int spi_nor_rww_start_rdst(struct spi_nor *nor)
641 {
642 	struct spi_nor_rww *rww = &nor->rww;
643 
644 	guard(mutex)(&nor->lock);
645 
646 	if (rww->ongoing_io || rww->ongoing_rd)
647 		return -EAGAIN;
648 
649 	rww->ongoing_io = true;
650 	rww->ongoing_rd = true;
651 
652 	return 0;
653 }
654 
655 static void spi_nor_rww_end_rdst(struct spi_nor *nor)
656 {
657 	struct spi_nor_rww *rww = &nor->rww;
658 
659 	guard(mutex)(&nor->lock);
660 
661 	rww->ongoing_io = false;
662 	rww->ongoing_rd = false;
663 }
664 
665 static int spi_nor_lock_rdst(struct spi_nor *nor)
666 {
667 	if (spi_nor_use_parallel_locking(nor))
668 		return spi_nor_rww_start_rdst(nor);
669 
670 	return 0;
671 }
672 
673 static void spi_nor_unlock_rdst(struct spi_nor *nor)
674 {
675 	if (spi_nor_use_parallel_locking(nor)) {
676 		spi_nor_rww_end_rdst(nor);
677 		wake_up(&nor->rww.wait);
678 	}
679 }
680 
681 /**
682  * spi_nor_ready() - Query the flash to see if it is ready for new commands.
683  * @nor:	pointer to 'struct spi_nor'.
684  *
685  * Return: 1 if ready, 0 if not ready, -errno on errors.
686  */
687 static int spi_nor_ready(struct spi_nor *nor)
688 {
689 	int ret;
690 
691 	ret = spi_nor_lock_rdst(nor);
692 	if (ret)
693 		return 0;
694 
695 	/* Flashes might override the standard routine. */
696 	if (nor->params->ready)
697 		ret = nor->params->ready(nor);
698 	else
699 		ret = spi_nor_sr_ready(nor);
700 
701 	spi_nor_unlock_rdst(nor);
702 
703 	return ret;
704 }
705 
706 /**
707  * spi_nor_wait_till_ready_with_timeout() - Service routine to read the
708  * Status Register until ready, or timeout occurs.
709  * @nor:		pointer to "struct spi_nor".
710  * @timeout_jiffies:	jiffies to wait until timeout.
711  *
712  * Return: 0 on success, -errno otherwise.
713  */
714 static int spi_nor_wait_till_ready_with_timeout(struct spi_nor *nor,
715 						unsigned long timeout_jiffies)
716 {
717 	unsigned long deadline;
718 	int timeout = 0, ret;
719 
720 	deadline = jiffies + timeout_jiffies;
721 
722 	while (!timeout) {
723 		if (time_after_eq(jiffies, deadline))
724 			timeout = 1;
725 
726 		ret = spi_nor_ready(nor);
727 		if (ret < 0)
728 			return ret;
729 		if (ret)
730 			return 0;
731 
732 		cond_resched();
733 	}
734 
735 	dev_dbg(nor->dev, "flash operation timed out\n");
736 
737 	return -ETIMEDOUT;
738 }
739 
740 /**
741  * spi_nor_wait_till_ready() - Wait for a predefined amount of time for the
742  * flash to be ready, or timeout occurs.
743  * @nor:	pointer to "struct spi_nor".
744  *
745  * Return: 0 on success, -errno otherwise.
746  */
747 int spi_nor_wait_till_ready(struct spi_nor *nor)
748 {
749 	return spi_nor_wait_till_ready_with_timeout(nor,
750 						    DEFAULT_READY_WAIT_JIFFIES);
751 }
752 
753 /**
754  * spi_nor_global_block_unlock() - Unlock Global Block Protection.
755  * @nor:	pointer to 'struct spi_nor'.
756  *
757  * Return: 0 on success, -errno otherwise.
758  */
759 int spi_nor_global_block_unlock(struct spi_nor *nor)
760 {
761 	int ret;
762 
763 	ret = spi_nor_write_enable(nor);
764 	if (ret)
765 		return ret;
766 
767 	if (nor->spimem) {
768 		struct spi_mem_op op = SPI_NOR_GBULK_OP;
769 
770 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
771 
772 		ret = spi_mem_exec_op(nor->spimem, &op);
773 	} else {
774 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_GBULK,
775 						       NULL, 0);
776 	}
777 
778 	if (ret) {
779 		dev_dbg(nor->dev, "error %d on Global Block Unlock\n", ret);
780 		return ret;
781 	}
782 
783 	return spi_nor_wait_till_ready(nor);
784 }
785 
786 /**
787  * spi_nor_write_sr() - Write the Status Register.
788  * @nor:	pointer to 'struct spi_nor'.
789  * @sr:		pointer to DMA-able buffer to write to the Status Register.
790  * @len:	number of bytes to write to the Status Register.
791  *
792  * Return: 0 on success, -errno otherwise.
793  */
794 int spi_nor_write_sr(struct spi_nor *nor, const u8 *sr, size_t len)
795 {
796 	int ret;
797 
798 	ret = spi_nor_write_enable(nor);
799 	if (ret)
800 		return ret;
801 
802 	if (nor->spimem) {
803 		struct spi_mem_op op = SPI_NOR_WRSR_OP(sr, len);
804 
805 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
806 
807 		ret = spi_mem_exec_op(nor->spimem, &op);
808 	} else {
809 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR, sr,
810 						       len);
811 	}
812 
813 	if (ret) {
814 		dev_dbg(nor->dev, "error %d writing SR\n", ret);
815 		return ret;
816 	}
817 
818 	return spi_nor_wait_till_ready(nor);
819 }
820 
821 /**
822  * spi_nor_write_sr1_and_check() - Write one byte to the Status Register 1 and
823  * ensure that the byte written match the received value.
824  * @nor:	pointer to a 'struct spi_nor'.
825  * @sr1:	byte value to be written to the Status Register.
826  *
827  * Return: 0 on success, -errno otherwise.
828  */
829 static int spi_nor_write_sr1_and_check(struct spi_nor *nor, u8 sr1)
830 {
831 	int ret;
832 
833 	nor->bouncebuf[0] = sr1;
834 
835 	ret = spi_nor_write_sr(nor, nor->bouncebuf, 1);
836 	if (ret)
837 		return ret;
838 
839 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
840 	if (ret)
841 		return ret;
842 
843 	if (nor->bouncebuf[0] != sr1) {
844 		dev_dbg(nor->dev, "SR1: read back test failed\n");
845 		return -EIO;
846 	}
847 
848 	return 0;
849 }
850 
851 /**
852  * spi_nor_write_16bit_sr_and_check() - Write the Status Register 1 and the
853  * Status Register 2 in one shot. Ensure that the byte written in the Status
854  * Register 1 match the received value, and that the 16-bit Write did not
855  * affect what was already in the Status Register 2.
856  * @nor:	pointer to a 'struct spi_nor'.
857  * @sr1:	byte value to be written to the Status Register 1.
858  *
859  * Return: 0 on success, -errno otherwise.
860  */
861 static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1)
862 {
863 	int ret;
864 	u8 *sr_cr = nor->bouncebuf;
865 	u8 cr_written;
866 
867 	/* Make sure we don't overwrite the contents of Status Register 2. */
868 	if (!(nor->flags & SNOR_F_NO_READ_CR)) {
869 		ret = spi_nor_read_cr(nor, &sr_cr[1]);
870 		if (ret)
871 			return ret;
872 	} else if ((spi_nor_get_protocol_width(nor->read_proto) == 4 ||
873 		    spi_nor_get_protocol_width(nor->write_proto) == 4) &&
874 		   nor->params->quad_enable) {
875 		/*
876 		 * If the Status Register 2 Read command (35h) is not
877 		 * supported, we should at least be sure we don't
878 		 * change the value of the SR2 Quad Enable bit.
879 		 *
880 		 * When the Quad Enable method is set and the buswidth is 4, we
881 		 * can safely assume that the value of the QE bit is one, as a
882 		 * consequence of the nor->params->quad_enable() call.
883 		 *
884 		 * According to the JESD216 revB standard, BFPT DWORDS[15],
885 		 * bits 22:20, the 16-bit Write Status (01h) command is
886 		 * available just for the cases in which the QE bit is
887 		 * described in SR2 at BIT(1).
888 		 */
889 		sr_cr[1] = SR2_QUAD_EN_BIT1;
890 	} else {
891 		sr_cr[1] = 0;
892 	}
893 
894 	sr_cr[0] = sr1;
895 
896 	ret = spi_nor_write_sr(nor, sr_cr, 2);
897 	if (ret)
898 		return ret;
899 
900 	ret = spi_nor_read_sr(nor, sr_cr);
901 	if (ret)
902 		return ret;
903 
904 	if (sr1 != sr_cr[0]) {
905 		dev_dbg(nor->dev, "SR: Read back test failed\n");
906 		return -EIO;
907 	}
908 
909 	if (nor->flags & SNOR_F_NO_READ_CR)
910 		return 0;
911 
912 	cr_written = sr_cr[1];
913 
914 	ret = spi_nor_read_cr(nor, &sr_cr[1]);
915 	if (ret)
916 		return ret;
917 
918 	if (cr_written != sr_cr[1]) {
919 		dev_dbg(nor->dev, "CR: read back test failed\n");
920 		return -EIO;
921 	}
922 
923 	return 0;
924 }
925 
926 /**
927  * spi_nor_write_16bit_cr_and_check() - Write the Status Register 1 and the
928  * Configuration Register in one shot. Ensure that the byte written in the
929  * Configuration Register match the received value, and that the 16-bit Write
930  * did not affect what was already in the Status Register 1.
931  * @nor:	pointer to a 'struct spi_nor'.
932  * @cr:		byte value to be written to the Configuration Register.
933  *
934  * Return: 0 on success, -errno otherwise.
935  */
936 int spi_nor_write_16bit_cr_and_check(struct spi_nor *nor, u8 cr)
937 {
938 	int ret;
939 	u8 *sr_cr = nor->bouncebuf;
940 	u8 sr_written;
941 
942 	/* Keep the current value of the Status Register 1. */
943 	ret = spi_nor_read_sr(nor, sr_cr);
944 	if (ret)
945 		return ret;
946 
947 	sr_cr[1] = cr;
948 
949 	ret = spi_nor_write_sr(nor, sr_cr, 2);
950 	if (ret)
951 		return ret;
952 
953 	sr_written = sr_cr[0];
954 
955 	ret = spi_nor_read_sr(nor, sr_cr);
956 	if (ret)
957 		return ret;
958 
959 	if (sr_written != sr_cr[0]) {
960 		dev_dbg(nor->dev, "SR: Read back test failed\n");
961 		return -EIO;
962 	}
963 
964 	if (nor->flags & SNOR_F_NO_READ_CR)
965 		return 0;
966 
967 	ret = spi_nor_read_cr(nor, &sr_cr[1]);
968 	if (ret)
969 		return ret;
970 
971 	if (cr != sr_cr[1]) {
972 		dev_dbg(nor->dev, "CR: read back test failed\n");
973 		return -EIO;
974 	}
975 
976 	return 0;
977 }
978 
979 /**
980  * spi_nor_write_16bit_sr_cr_and_check() - Write the Status Register 1 and the
981  * Configuration Register in one shot. Ensure that the bytes written in both
982  * registers match the received value.
983  * @nor:	pointer to a 'struct spi_nor'.
984  * @regs:	two-byte array with values to be written to the status and
985  *		configuration registers.
986  *
987  * Return: 0 on success, -errno otherwise.
988  */
989 static int spi_nor_write_16bit_sr_cr_and_check(struct spi_nor *nor, const u8 *regs)
990 {
991 	u8 written_regs[2];
992 	int ret;
993 
994 	written_regs[0] = regs[0];
995 	written_regs[1] = regs[1];
996 	nor->bouncebuf[0] = regs[0];
997 	nor->bouncebuf[1] = regs[1];
998 
999 	ret = spi_nor_write_sr(nor, nor->bouncebuf, 2);
1000 	if (ret)
1001 		return ret;
1002 
1003 	ret = spi_nor_read_sr(nor, &nor->bouncebuf[0]);
1004 	if (ret)
1005 		return ret;
1006 
1007 	if (written_regs[0] != nor->bouncebuf[0]) {
1008 		dev_dbg(nor->dev, "SR: Read back test failed\n");
1009 		return -EIO;
1010 	}
1011 
1012 	if (nor->flags & SNOR_F_NO_READ_CR)
1013 		return 0;
1014 
1015 	ret = spi_nor_read_cr(nor, &nor->bouncebuf[1]);
1016 	if (ret)
1017 		return ret;
1018 
1019 	if (written_regs[1] != nor->bouncebuf[1]) {
1020 		dev_dbg(nor->dev, "CR: read back test failed\n");
1021 		return -EIO;
1022 	}
1023 
1024 	return 0;
1025 }
1026 
1027 /**
1028  * spi_nor_write_sr_and_check() - Write the Status Register 1 and ensure that
1029  * the byte written match the received value without affecting other bits in the
1030  * Status Register 1 and 2.
1031  * @nor:	pointer to a 'struct spi_nor'.
1032  * @sr1:	byte value to be written to the Status Register.
1033  *
1034  * Return: 0 on success, -errno otherwise.
1035  */
1036 int spi_nor_write_sr_and_check(struct spi_nor *nor, u8 sr1)
1037 {
1038 	if (nor->flags & SNOR_F_HAS_16BIT_SR)
1039 		return spi_nor_write_16bit_sr_and_check(nor, sr1);
1040 
1041 	return spi_nor_write_sr1_and_check(nor, sr1);
1042 }
1043 
1044 /**
1045  * spi_nor_write_sr_cr_and_check() - Write the Status Register 1 and ensure that
1046  * the byte written match the received value. Same for the Control Register if
1047  * available.
1048  * @nor:	pointer to a 'struct spi_nor'.
1049  * @regs:	byte array to be written to the registers.
1050  *
1051  * Return: 0 on success, -errno otherwise.
1052  */
1053 int spi_nor_write_sr_cr_and_check(struct spi_nor *nor, const u8 *regs)
1054 {
1055 	if (nor->flags & SNOR_F_HAS_16BIT_SR)
1056 		return spi_nor_write_16bit_sr_cr_and_check(nor, regs);
1057 
1058 	return spi_nor_write_sr1_and_check(nor, regs[0]);
1059 }
1060 
1061 /**
1062  * spi_nor_write_sr2() - Write the Status Register 2 using the
1063  * SPINOR_OP_WRSR2 (3eh) command.
1064  * @nor:	pointer to 'struct spi_nor'.
1065  * @sr2:	pointer to DMA-able buffer to write to the Status Register 2.
1066  *
1067  * Return: 0 on success, -errno otherwise.
1068  */
1069 static int spi_nor_write_sr2(struct spi_nor *nor, const u8 *sr2)
1070 {
1071 	int ret;
1072 
1073 	ret = spi_nor_write_enable(nor);
1074 	if (ret)
1075 		return ret;
1076 
1077 	if (nor->spimem) {
1078 		struct spi_mem_op op = SPI_NOR_WRSR2_OP(sr2);
1079 
1080 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1081 
1082 		ret = spi_mem_exec_op(nor->spimem, &op);
1083 	} else {
1084 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR2,
1085 						       sr2, 1);
1086 	}
1087 
1088 	if (ret) {
1089 		dev_dbg(nor->dev, "error %d writing SR2\n", ret);
1090 		return ret;
1091 	}
1092 
1093 	return spi_nor_wait_till_ready(nor);
1094 }
1095 
1096 /**
1097  * spi_nor_read_sr2() - Read the Status Register 2 using the
1098  * SPINOR_OP_RDSR2 (3fh) command.
1099  * @nor:	pointer to 'struct spi_nor'.
1100  * @sr2:	pointer to DMA-able buffer where the value of the
1101  *		Status Register 2 will be written.
1102  *
1103  * Return: 0 on success, -errno otherwise.
1104  */
1105 static int spi_nor_read_sr2(struct spi_nor *nor, u8 *sr2)
1106 {
1107 	int ret;
1108 
1109 	if (nor->spimem) {
1110 		struct spi_mem_op op = SPI_NOR_RDSR2_OP(sr2);
1111 
1112 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1113 
1114 		ret = spi_mem_exec_op(nor->spimem, &op);
1115 	} else {
1116 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR2, sr2,
1117 						      1);
1118 	}
1119 
1120 	if (ret)
1121 		dev_dbg(nor->dev, "error %d reading SR2\n", ret);
1122 
1123 	return ret;
1124 }
1125 
1126 /**
1127  * spi_nor_erase_die() - Erase the entire die.
1128  * @nor:	pointer to 'struct spi_nor'.
1129  * @addr:	address of the die.
1130  * @die_size:	size of the die.
1131  *
1132  * Return: 0 on success, -errno otherwise.
1133  */
1134 static int spi_nor_erase_die(struct spi_nor *nor, loff_t addr, size_t die_size)
1135 {
1136 	bool multi_die = nor->mtd.size != die_size;
1137 	int ret;
1138 
1139 	dev_dbg(nor->dev, " %lldKiB\n", (long long)(die_size >> 10));
1140 
1141 	if (nor->spimem) {
1142 		struct spi_mem_op op =
1143 			SPI_NOR_DIE_ERASE_OP(nor->params->die_erase_opcode,
1144 					     nor->addr_nbytes, addr, multi_die);
1145 
1146 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1147 
1148 		ret = spi_mem_exec_op(nor->spimem, &op);
1149 	} else {
1150 		if (multi_die)
1151 			return -EOPNOTSUPP;
1152 
1153 		ret = spi_nor_controller_ops_write_reg(nor,
1154 						       SPINOR_OP_CHIP_ERASE,
1155 						       NULL, 0);
1156 	}
1157 
1158 	if (ret)
1159 		dev_dbg(nor->dev, "error %d erasing chip\n", ret);
1160 
1161 	return ret;
1162 }
1163 
1164 static u8 spi_nor_convert_opcode(u8 opcode, const u8 table[][2], size_t size)
1165 {
1166 	size_t i;
1167 
1168 	for (i = 0; i < size; i++)
1169 		if (table[i][0] == opcode)
1170 			return table[i][1];
1171 
1172 	/* No conversion found, keep input op code. */
1173 	return opcode;
1174 }
1175 
1176 u8 spi_nor_convert_3to4_read(u8 opcode)
1177 {
1178 	static const u8 spi_nor_3to4_read[][2] = {
1179 		{ SPINOR_OP_READ,	SPINOR_OP_READ_4B },
1180 		{ SPINOR_OP_READ_FAST,	SPINOR_OP_READ_FAST_4B },
1181 		{ SPINOR_OP_READ_1_1_2,	SPINOR_OP_READ_1_1_2_4B },
1182 		{ SPINOR_OP_READ_1_2_2,	SPINOR_OP_READ_1_2_2_4B },
1183 		{ SPINOR_OP_READ_1_1_4,	SPINOR_OP_READ_1_1_4_4B },
1184 		{ SPINOR_OP_READ_1_4_4,	SPINOR_OP_READ_1_4_4_4B },
1185 		{ SPINOR_OP_READ_1_1_8,	SPINOR_OP_READ_1_1_8_4B },
1186 		{ SPINOR_OP_READ_1_8_8,	SPINOR_OP_READ_1_8_8_4B },
1187 
1188 		{ SPINOR_OP_READ_1_1_1_DTR,	SPINOR_OP_READ_1_1_1_DTR_4B },
1189 		{ SPINOR_OP_READ_1_2_2_DTR,	SPINOR_OP_READ_1_2_2_DTR_4B },
1190 		{ SPINOR_OP_READ_1_4_4_DTR,	SPINOR_OP_READ_1_4_4_DTR_4B },
1191 	};
1192 
1193 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_read,
1194 				      ARRAY_SIZE(spi_nor_3to4_read));
1195 }
1196 
1197 static u8 spi_nor_convert_3to4_program(u8 opcode)
1198 {
1199 	static const u8 spi_nor_3to4_program[][2] = {
1200 		{ SPINOR_OP_PP,		SPINOR_OP_PP_4B },
1201 		{ SPINOR_OP_PP_1_1_4,	SPINOR_OP_PP_1_1_4_4B },
1202 		{ SPINOR_OP_PP_1_4_4,	SPINOR_OP_PP_1_4_4_4B },
1203 		{ SPINOR_OP_PP_1_1_8,	SPINOR_OP_PP_1_1_8_4B },
1204 		{ SPINOR_OP_PP_1_8_8,	SPINOR_OP_PP_1_8_8_4B },
1205 	};
1206 
1207 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_program,
1208 				      ARRAY_SIZE(spi_nor_3to4_program));
1209 }
1210 
1211 static u8 spi_nor_convert_3to4_erase(u8 opcode)
1212 {
1213 	static const u8 spi_nor_3to4_erase[][2] = {
1214 		{ SPINOR_OP_BE_4K,	SPINOR_OP_BE_4K_4B },
1215 		{ SPINOR_OP_BE_32K,	SPINOR_OP_BE_32K_4B },
1216 		{ SPINOR_OP_SE,		SPINOR_OP_SE_4B },
1217 	};
1218 
1219 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_erase,
1220 				      ARRAY_SIZE(spi_nor_3to4_erase));
1221 }
1222 
1223 static bool spi_nor_has_uniform_erase(const struct spi_nor *nor)
1224 {
1225 	return !!nor->params->erase_map.uniform_region.erase_mask;
1226 }
1227 
1228 static void spi_nor_set_4byte_opcodes(struct spi_nor *nor)
1229 {
1230 	nor->read_opcode = spi_nor_convert_3to4_read(nor->read_opcode);
1231 	nor->program_opcode = spi_nor_convert_3to4_program(nor->program_opcode);
1232 	nor->erase_opcode = spi_nor_convert_3to4_erase(nor->erase_opcode);
1233 
1234 	if (!spi_nor_has_uniform_erase(nor)) {
1235 		struct spi_nor_erase_map *map = &nor->params->erase_map;
1236 		struct spi_nor_erase_type *erase;
1237 		int i;
1238 
1239 		for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
1240 			erase = &map->erase_type[i];
1241 			erase->opcode =
1242 				spi_nor_convert_3to4_erase(erase->opcode);
1243 		}
1244 	}
1245 }
1246 
1247 static int spi_nor_prep(struct spi_nor *nor)
1248 {
1249 	int ret = 0;
1250 
1251 	if (nor->controller_ops && nor->controller_ops->prepare)
1252 		ret = nor->controller_ops->prepare(nor);
1253 
1254 	return ret;
1255 }
1256 
1257 static void spi_nor_unprep(struct spi_nor *nor)
1258 {
1259 	if (nor->controller_ops && nor->controller_ops->unprepare)
1260 		nor->controller_ops->unprepare(nor);
1261 }
1262 
1263 static void spi_nor_offset_to_banks(u64 bank_size, loff_t start, size_t len,
1264 				    u8 *first, u8 *last)
1265 {
1266 	/* This is currently safe, the number of banks being very small */
1267 	*first = DIV_ROUND_DOWN_ULL(start, bank_size);
1268 	*last = DIV_ROUND_DOWN_ULL(start + len - 1, bank_size);
1269 }
1270 
1271 /* Generic helpers for internal locking and serialization */
1272 static bool spi_nor_rww_start_io(struct spi_nor *nor)
1273 {
1274 	struct spi_nor_rww *rww = &nor->rww;
1275 
1276 	guard(mutex)(&nor->lock);
1277 
1278 	if (rww->ongoing_io)
1279 		return false;
1280 
1281 	rww->ongoing_io = true;
1282 
1283 	return true;
1284 }
1285 
1286 static void spi_nor_rww_end_io(struct spi_nor *nor)
1287 {
1288 	guard(mutex)(&nor->lock);
1289 	nor->rww.ongoing_io = false;
1290 }
1291 
1292 static int spi_nor_lock_device(struct spi_nor *nor)
1293 {
1294 	if (!spi_nor_use_parallel_locking(nor))
1295 		return 0;
1296 
1297 	return wait_event_killable(nor->rww.wait, spi_nor_rww_start_io(nor));
1298 }
1299 
1300 static void spi_nor_unlock_device(struct spi_nor *nor)
1301 {
1302 	if (spi_nor_use_parallel_locking(nor)) {
1303 		spi_nor_rww_end_io(nor);
1304 		wake_up(&nor->rww.wait);
1305 	}
1306 }
1307 
1308 /* Generic helpers for internal locking and serialization */
1309 static bool spi_nor_rww_start_exclusive(struct spi_nor *nor)
1310 {
1311 	struct spi_nor_rww *rww = &nor->rww;
1312 
1313 	mutex_lock(&nor->lock);
1314 
1315 	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
1316 		return false;
1317 
1318 	rww->ongoing_io = true;
1319 	rww->ongoing_rd = true;
1320 	rww->ongoing_pe = true;
1321 
1322 	return true;
1323 }
1324 
1325 static void spi_nor_rww_end_exclusive(struct spi_nor *nor)
1326 {
1327 	struct spi_nor_rww *rww = &nor->rww;
1328 
1329 	guard(mutex)(&nor->lock);
1330 	rww->ongoing_io = false;
1331 	rww->ongoing_rd = false;
1332 	rww->ongoing_pe = false;
1333 }
1334 
1335 int spi_nor_prep_and_lock(struct spi_nor *nor)
1336 {
1337 	int ret;
1338 
1339 	ret = spi_nor_prep(nor);
1340 	if (ret)
1341 		return ret;
1342 
1343 	if (!spi_nor_use_parallel_locking(nor))
1344 		mutex_lock(&nor->lock);
1345 	else
1346 		ret = wait_event_killable(nor->rww.wait,
1347 					  spi_nor_rww_start_exclusive(nor));
1348 
1349 	return ret;
1350 }
1351 
1352 void spi_nor_unlock_and_unprep(struct spi_nor *nor)
1353 {
1354 	if (!spi_nor_use_parallel_locking(nor)) {
1355 		mutex_unlock(&nor->lock);
1356 	} else {
1357 		spi_nor_rww_end_exclusive(nor);
1358 		wake_up(&nor->rww.wait);
1359 	}
1360 
1361 	spi_nor_unprep(nor);
1362 }
1363 
1364 /* Internal locking helpers for program and erase operations */
1365 static bool spi_nor_rww_start_pe(struct spi_nor *nor, loff_t start, size_t len)
1366 {
1367 	struct spi_nor_rww *rww = &nor->rww;
1368 	unsigned int used_banks = 0;
1369 	u8 first, last;
1370 	int bank;
1371 
1372 	guard(mutex)(&nor->lock);
1373 
1374 	if (rww->ongoing_io || rww->ongoing_rd || rww->ongoing_pe)
1375 		return false;
1376 
1377 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1378 	for (bank = first; bank <= last; bank++) {
1379 		if (rww->used_banks & BIT(bank))
1380 			return false;
1381 
1382 		used_banks |= BIT(bank);
1383 	}
1384 
1385 	rww->used_banks |= used_banks;
1386 	rww->ongoing_pe = true;
1387 
1388 	return true;
1389 }
1390 
1391 static void spi_nor_rww_end_pe(struct spi_nor *nor, loff_t start, size_t len)
1392 {
1393 	struct spi_nor_rww *rww = &nor->rww;
1394 	u8 first, last;
1395 	int bank;
1396 
1397 	guard(mutex)(&nor->lock);
1398 
1399 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1400 	for (bank = first; bank <= last; bank++)
1401 		rww->used_banks &= ~BIT(bank);
1402 
1403 	rww->ongoing_pe = false;
1404 }
1405 
1406 static int spi_nor_prep_and_lock_pe(struct spi_nor *nor, loff_t start, size_t len)
1407 {
1408 	int ret;
1409 
1410 	ret = spi_nor_prep(nor);
1411 	if (ret)
1412 		return ret;
1413 
1414 	if (!spi_nor_use_parallel_locking(nor))
1415 		mutex_lock(&nor->lock);
1416 	else
1417 		ret = wait_event_killable(nor->rww.wait,
1418 					  spi_nor_rww_start_pe(nor, start, len));
1419 
1420 	return ret;
1421 }
1422 
1423 static void spi_nor_unlock_and_unprep_pe(struct spi_nor *nor, loff_t start, size_t len)
1424 {
1425 	if (!spi_nor_use_parallel_locking(nor)) {
1426 		mutex_unlock(&nor->lock);
1427 	} else {
1428 		spi_nor_rww_end_pe(nor, start, len);
1429 		wake_up(&nor->rww.wait);
1430 	}
1431 
1432 	spi_nor_unprep(nor);
1433 }
1434 
1435 /* Internal locking helpers for read operations */
1436 static bool spi_nor_rww_start_rd(struct spi_nor *nor, loff_t start, size_t len)
1437 {
1438 	struct spi_nor_rww *rww = &nor->rww;
1439 	unsigned int used_banks = 0;
1440 	u8 first, last;
1441 	int bank;
1442 
1443 	guard(mutex)(&nor->lock);
1444 
1445 	if (rww->ongoing_io || rww->ongoing_rd)
1446 		return false;
1447 
1448 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1449 	for (bank = first; bank <= last; bank++) {
1450 		if (rww->used_banks & BIT(bank))
1451 			return false;
1452 
1453 		used_banks |= BIT(bank);
1454 	}
1455 
1456 	rww->used_banks |= used_banks;
1457 	rww->ongoing_io = true;
1458 	rww->ongoing_rd = true;
1459 
1460 	return true;
1461 }
1462 
1463 static void spi_nor_rww_end_rd(struct spi_nor *nor, loff_t start, size_t len)
1464 {
1465 	struct spi_nor_rww *rww = &nor->rww;
1466 	u8 first, last;
1467 	int bank;
1468 
1469 	guard(mutex)(&nor->lock);
1470 
1471 	spi_nor_offset_to_banks(nor->params->bank_size, start, len, &first, &last);
1472 	for (bank = first; bank <= last; bank++)
1473 		nor->rww.used_banks &= ~BIT(bank);
1474 
1475 	rww->ongoing_io = false;
1476 	rww->ongoing_rd = false;
1477 }
1478 
1479 static int spi_nor_prep_and_lock_rd(struct spi_nor *nor, loff_t start, size_t len)
1480 {
1481 	int ret;
1482 
1483 	ret = spi_nor_prep(nor);
1484 	if (ret)
1485 		return ret;
1486 
1487 	if (!spi_nor_use_parallel_locking(nor))
1488 		mutex_lock(&nor->lock);
1489 	else
1490 		ret = wait_event_killable(nor->rww.wait,
1491 					  spi_nor_rww_start_rd(nor, start, len));
1492 
1493 	return ret;
1494 }
1495 
1496 static void spi_nor_unlock_and_unprep_rd(struct spi_nor *nor, loff_t start, size_t len)
1497 {
1498 	if (!spi_nor_use_parallel_locking(nor)) {
1499 		mutex_unlock(&nor->lock);
1500 	} else {
1501 		spi_nor_rww_end_rd(nor, start, len);
1502 		wake_up(&nor->rww.wait);
1503 	}
1504 
1505 	spi_nor_unprep(nor);
1506 }
1507 
1508 /*
1509  * Initiate the erasure of a single sector
1510  */
1511 int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
1512 {
1513 	int i;
1514 
1515 	if (nor->spimem) {
1516 		struct spi_mem_op op =
1517 			SPI_NOR_SECTOR_ERASE_OP(nor->erase_opcode,
1518 						nor->addr_nbytes, addr);
1519 
1520 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1521 
1522 		return spi_mem_exec_op(nor->spimem, &op);
1523 	} else if (nor->controller_ops->erase) {
1524 		return spi_nor_controller_ops_erase(nor, addr);
1525 	}
1526 
1527 	/*
1528 	 * Default implementation, if driver doesn't have a specialized HW
1529 	 * control
1530 	 */
1531 	for (i = nor->addr_nbytes - 1; i >= 0; i--) {
1532 		nor->bouncebuf[i] = addr & 0xff;
1533 		addr >>= 8;
1534 	}
1535 
1536 	return spi_nor_controller_ops_write_reg(nor, nor->erase_opcode,
1537 						nor->bouncebuf, nor->addr_nbytes);
1538 }
1539 
1540 /**
1541  * spi_nor_div_by_erase_size() - calculate remainder and update new dividend
1542  * @erase:	pointer to a structure that describes a SPI NOR erase type
1543  * @dividend:	dividend value
1544  * @remainder:	pointer to u32 remainder (will be updated)
1545  *
1546  * Return: the result of the division
1547  */
1548 static u64 spi_nor_div_by_erase_size(const struct spi_nor_erase_type *erase,
1549 				     u64 dividend, u32 *remainder)
1550 {
1551 	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
1552 	*remainder = (u32)dividend & erase->size_mask;
1553 	return dividend >> erase->size_shift;
1554 }
1555 
1556 /**
1557  * spi_nor_find_best_erase_type() - find the best erase type for the given
1558  *				    offset in the serial flash memory and the
1559  *				    number of bytes to erase. The region in
1560  *				    which the address fits is expected to be
1561  *				    provided.
1562  * @map:	the erase map of the SPI NOR
1563  * @region:	pointer to a structure that describes a SPI NOR erase region
1564  * @addr:	offset in the serial flash memory
1565  * @len:	number of bytes to erase
1566  *
1567  * Return: a pointer to the best fitted erase type, NULL otherwise.
1568  */
1569 static const struct spi_nor_erase_type *
1570 spi_nor_find_best_erase_type(const struct spi_nor_erase_map *map,
1571 			     const struct spi_nor_erase_region *region,
1572 			     u64 addr, u32 len)
1573 {
1574 	const struct spi_nor_erase_type *erase;
1575 	u32 rem;
1576 	int i;
1577 
1578 	/*
1579 	 * Erase types are ordered by size, with the smallest erase type at
1580 	 * index 0.
1581 	 */
1582 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
1583 		/* Does the erase region support the tested erase type? */
1584 		if (!(region->erase_mask & BIT(i)))
1585 			continue;
1586 
1587 		erase = &map->erase_type[i];
1588 		if (!erase->size)
1589 			continue;
1590 
1591 		/* Alignment is not mandatory for overlaid regions */
1592 		if (region->overlaid && region->size <= len)
1593 			return erase;
1594 
1595 		/* Don't erase more than what the user has asked for. */
1596 		if (erase->size > len)
1597 			continue;
1598 
1599 		spi_nor_div_by_erase_size(erase, addr, &rem);
1600 		if (!rem)
1601 			return erase;
1602 	}
1603 
1604 	return NULL;
1605 }
1606 
1607 /**
1608  * spi_nor_init_erase_cmd() - initialize an erase command
1609  * @region:	pointer to a structure that describes a SPI NOR erase region
1610  * @erase:	pointer to a structure that describes a SPI NOR erase type
1611  *
1612  * Return: the pointer to the allocated erase command, ERR_PTR(-errno)
1613  *	   otherwise.
1614  */
1615 static struct spi_nor_erase_command *
1616 spi_nor_init_erase_cmd(const struct spi_nor_erase_region *region,
1617 		       const struct spi_nor_erase_type *erase)
1618 {
1619 	struct spi_nor_erase_command *cmd;
1620 
1621 	cmd = kmalloc_obj(*cmd);
1622 	if (!cmd)
1623 		return ERR_PTR(-ENOMEM);
1624 
1625 	INIT_LIST_HEAD(&cmd->list);
1626 	cmd->opcode = erase->opcode;
1627 	cmd->count = 1;
1628 
1629 	if (region->overlaid)
1630 		cmd->size = region->size;
1631 	else
1632 		cmd->size = erase->size;
1633 
1634 	return cmd;
1635 }
1636 
1637 /**
1638  * spi_nor_destroy_erase_cmd_list() - destroy erase command list
1639  * @erase_list:	list of erase commands
1640  */
1641 static void spi_nor_destroy_erase_cmd_list(struct list_head *erase_list)
1642 {
1643 	struct spi_nor_erase_command *cmd, *next;
1644 
1645 	list_for_each_entry_safe(cmd, next, erase_list, list) {
1646 		list_del(&cmd->list);
1647 		kfree(cmd);
1648 	}
1649 }
1650 
1651 /**
1652  * spi_nor_init_erase_cmd_list() - initialize erase command list
1653  * @nor:	pointer to a 'struct spi_nor'
1654  * @erase_list:	list of erase commands to be executed once we validate that the
1655  *		erase can be performed
1656  * @addr:	offset in the serial flash memory
1657  * @len:	number of bytes to erase
1658  *
1659  * Builds the list of best fitted erase commands and verifies if the erase can
1660  * be performed.
1661  *
1662  * Return: 0 on success, -errno otherwise.
1663  */
1664 static int spi_nor_init_erase_cmd_list(struct spi_nor *nor,
1665 				       struct list_head *erase_list,
1666 				       u64 addr, u32 len)
1667 {
1668 	const struct spi_nor_erase_map *map = &nor->params->erase_map;
1669 	const struct spi_nor_erase_type *erase, *prev_erase = NULL;
1670 	struct spi_nor_erase_region *region;
1671 	struct spi_nor_erase_command *cmd = NULL;
1672 	u64 region_end;
1673 	unsigned int i;
1674 	int ret = -EINVAL;
1675 
1676 	for (i = 0; i < map->n_regions && len; i++) {
1677 		region = &map->regions[i];
1678 		region_end = region->offset + region->size;
1679 
1680 		while (len && addr >= region->offset && addr < region_end) {
1681 			erase = spi_nor_find_best_erase_type(map, region, addr,
1682 							     len);
1683 			if (!erase)
1684 				goto destroy_erase_cmd_list;
1685 
1686 			if (prev_erase != erase || erase->size != cmd->size ||
1687 			    region->overlaid) {
1688 				cmd = spi_nor_init_erase_cmd(region, erase);
1689 				if (IS_ERR(cmd)) {
1690 					ret = PTR_ERR(cmd);
1691 					goto destroy_erase_cmd_list;
1692 				}
1693 
1694 				list_add_tail(&cmd->list, erase_list);
1695 			} else {
1696 				cmd->count++;
1697 			}
1698 
1699 			len -= cmd->size;
1700 			addr += cmd->size;
1701 			prev_erase = erase;
1702 		}
1703 	}
1704 
1705 	return 0;
1706 
1707 destroy_erase_cmd_list:
1708 	spi_nor_destroy_erase_cmd_list(erase_list);
1709 	return ret;
1710 }
1711 
1712 /**
1713  * spi_nor_erase_multi_sectors() - perform a non-uniform erase
1714  * @nor:	pointer to a 'struct spi_nor'
1715  * @addr:	offset in the serial flash memory
1716  * @len:	number of bytes to erase
1717  *
1718  * Build a list of best fitted erase commands and execute it once we validate
1719  * that the erase can be performed.
1720  *
1721  * Return: 0 on success, -errno otherwise.
1722  */
1723 static int spi_nor_erase_multi_sectors(struct spi_nor *nor, u64 addr, u32 len)
1724 {
1725 	LIST_HEAD(erase_list);
1726 	struct spi_nor_erase_command *cmd, *next;
1727 	int ret;
1728 
1729 	ret = spi_nor_init_erase_cmd_list(nor, &erase_list, addr, len);
1730 	if (ret)
1731 		return ret;
1732 
1733 	list_for_each_entry_safe(cmd, next, &erase_list, list) {
1734 		nor->erase_opcode = cmd->opcode;
1735 		while (cmd->count) {
1736 			dev_vdbg(nor->dev, "erase_cmd->size = 0x%08x, erase_cmd->opcode = 0x%02x, erase_cmd->count = %u\n",
1737 				 cmd->size, cmd->opcode, cmd->count);
1738 
1739 			ret = spi_nor_lock_device(nor);
1740 			if (ret)
1741 				goto destroy_erase_cmd_list;
1742 
1743 			ret = spi_nor_write_enable(nor);
1744 			if (ret) {
1745 				spi_nor_unlock_device(nor);
1746 				goto destroy_erase_cmd_list;
1747 			}
1748 
1749 			ret = spi_nor_erase_sector(nor, addr);
1750 			spi_nor_unlock_device(nor);
1751 			if (ret)
1752 				goto destroy_erase_cmd_list;
1753 
1754 			ret = spi_nor_wait_till_ready(nor);
1755 			if (ret)
1756 				goto destroy_erase_cmd_list;
1757 
1758 			addr += cmd->size;
1759 			cmd->count--;
1760 		}
1761 		list_del(&cmd->list);
1762 		kfree(cmd);
1763 	}
1764 
1765 	return 0;
1766 
1767 destroy_erase_cmd_list:
1768 	spi_nor_destroy_erase_cmd_list(&erase_list);
1769 	return ret;
1770 }
1771 
1772 static int spi_nor_erase_dice(struct spi_nor *nor, loff_t addr,
1773 			      size_t len, size_t die_size)
1774 {
1775 	unsigned long timeout;
1776 	int ret;
1777 
1778 	/*
1779 	 * Scale the timeout linearly with the size of the flash, with
1780 	 * a minimum calibrated to an old 2MB flash. We could try to
1781 	 * pull these from CFI/SFDP, but these values should be good
1782 	 * enough for now.
1783 	 */
1784 	timeout = max(CHIP_ERASE_2MB_READY_WAIT_JIFFIES,
1785 		      CHIP_ERASE_2MB_READY_WAIT_JIFFIES *
1786 		      (unsigned long)(nor->mtd.size / SZ_2M));
1787 
1788 	do {
1789 		ret = spi_nor_lock_device(nor);
1790 		if (ret)
1791 			return ret;
1792 
1793 		ret = spi_nor_write_enable(nor);
1794 		if (ret) {
1795 			spi_nor_unlock_device(nor);
1796 			return ret;
1797 		}
1798 
1799 		ret = spi_nor_erase_die(nor, addr, die_size);
1800 
1801 		spi_nor_unlock_device(nor);
1802 		if (ret)
1803 			return ret;
1804 
1805 		ret = spi_nor_wait_till_ready_with_timeout(nor, timeout);
1806 		if (ret)
1807 			return ret;
1808 
1809 		addr += die_size;
1810 		len -= die_size;
1811 
1812 	} while (len);
1813 
1814 	return 0;
1815 }
1816 
1817 /*
1818  * Erase an address range on the nor chip.  The address range may extend
1819  * one or more erase sectors. Return an error if there is a problem erasing.
1820  */
1821 static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
1822 {
1823 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
1824 	u8 n_dice = nor->params->n_dice;
1825 	bool multi_die_erase = false;
1826 	u32 addr, len, rem;
1827 	size_t die_size;
1828 	int ret;
1829 
1830 	dev_dbg(nor->dev, "at 0x%llx, len %lld\n", (long long)instr->addr,
1831 			(long long)instr->len);
1832 
1833 	if (spi_nor_has_uniform_erase(nor)) {
1834 		div_u64_rem(instr->len, mtd->erasesize, &rem);
1835 		if (rem)
1836 			return -EINVAL;
1837 	}
1838 
1839 	addr = instr->addr;
1840 	len = instr->len;
1841 
1842 	if (n_dice) {
1843 		die_size = div_u64(mtd->size, n_dice);
1844 		if (!(len & (die_size - 1)) && !(addr & (die_size - 1)))
1845 			multi_die_erase = true;
1846 	} else {
1847 		die_size = mtd->size;
1848 	}
1849 
1850 	ret = spi_nor_prep_and_lock_pe(nor, instr->addr, instr->len);
1851 	if (ret)
1852 		return ret;
1853 
1854 	/* chip (die) erase? */
1855 	if ((len == mtd->size && !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) ||
1856 	    multi_die_erase) {
1857 		ret = spi_nor_erase_dice(nor, addr, len, die_size);
1858 		if (ret)
1859 			goto erase_err;
1860 
1861 	/* REVISIT in some cases we could speed up erasing large regions
1862 	 * by using SPINOR_OP_SE instead of SPINOR_OP_BE_4K.  We may have set up
1863 	 * to use "small sector erase", but that's not always optimal.
1864 	 */
1865 
1866 	/* "sector"-at-a-time erase */
1867 	} else if (spi_nor_has_uniform_erase(nor)) {
1868 		while (len) {
1869 			ret = spi_nor_lock_device(nor);
1870 			if (ret)
1871 				goto erase_err;
1872 
1873 			ret = spi_nor_write_enable(nor);
1874 			if (ret) {
1875 				spi_nor_unlock_device(nor);
1876 				goto erase_err;
1877 			}
1878 
1879 			ret = spi_nor_erase_sector(nor, addr);
1880 			spi_nor_unlock_device(nor);
1881 			if (ret)
1882 				goto erase_err;
1883 
1884 			ret = spi_nor_wait_till_ready(nor);
1885 			if (ret)
1886 				goto erase_err;
1887 
1888 			addr += mtd->erasesize;
1889 			len -= mtd->erasesize;
1890 		}
1891 
1892 	/* erase multiple sectors */
1893 	} else {
1894 		ret = spi_nor_erase_multi_sectors(nor, addr, len);
1895 		if (ret)
1896 			goto erase_err;
1897 	}
1898 
1899 	ret = spi_nor_write_disable(nor);
1900 
1901 erase_err:
1902 	spi_nor_unlock_and_unprep_pe(nor, instr->addr, instr->len);
1903 
1904 	return ret;
1905 }
1906 
1907 /**
1908  * spi_nor_sr1_bit6_quad_enable() - Set the Quad Enable BIT(6) in the Status
1909  * Register 1.
1910  * @nor:	pointer to a 'struct spi_nor'
1911  *
1912  * Bit 6 of the Status Register 1 is the QE bit for Macronix like QSPI memories.
1913  *
1914  * Return: 0 on success, -errno otherwise.
1915  */
1916 int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor)
1917 {
1918 	int ret;
1919 
1920 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
1921 	if (ret)
1922 		return ret;
1923 
1924 	if (nor->bouncebuf[0] & SR1_QUAD_EN_BIT6)
1925 		return 0;
1926 
1927 	nor->bouncebuf[0] |= SR1_QUAD_EN_BIT6;
1928 
1929 	return spi_nor_write_sr1_and_check(nor, nor->bouncebuf[0]);
1930 }
1931 
1932 /**
1933  * spi_nor_sr2_bit1_quad_enable() - set the Quad Enable BIT(1) in the Status
1934  * Register 2.
1935  * @nor:       pointer to a 'struct spi_nor'.
1936  *
1937  * Bit 1 of the Status Register 2 is the QE bit for Spansion like QSPI memories.
1938  *
1939  * Return: 0 on success, -errno otherwise.
1940  */
1941 int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor)
1942 {
1943 	int ret;
1944 
1945 	if (nor->flags & SNOR_F_NO_READ_CR)
1946 		return spi_nor_write_16bit_cr_and_check(nor, SR2_QUAD_EN_BIT1);
1947 
1948 	ret = spi_nor_read_cr(nor, nor->bouncebuf);
1949 	if (ret)
1950 		return ret;
1951 
1952 	if (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)
1953 		return 0;
1954 
1955 	nor->bouncebuf[0] |= SR2_QUAD_EN_BIT1;
1956 
1957 	return spi_nor_write_16bit_cr_and_check(nor, nor->bouncebuf[0]);
1958 }
1959 
1960 /**
1961  * spi_nor_sr2_bit7_quad_enable() - set QE bit in Status Register 2.
1962  * @nor:	pointer to a 'struct spi_nor'
1963  *
1964  * Set the Quad Enable (QE) bit in the Status Register 2.
1965  *
1966  * This is one of the procedures to set the QE bit described in the SFDP
1967  * (JESD216 rev B) specification but no manufacturer using this procedure has
1968  * been identified yet, hence the name of the function.
1969  *
1970  * Return: 0 on success, -errno otherwise.
1971  */
1972 int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor)
1973 {
1974 	u8 *sr2 = nor->bouncebuf;
1975 	int ret;
1976 	u8 sr2_written;
1977 
1978 	/* Check current Quad Enable bit value. */
1979 	ret = spi_nor_read_sr2(nor, sr2);
1980 	if (ret)
1981 		return ret;
1982 	if (*sr2 & SR2_QUAD_EN_BIT7)
1983 		return 0;
1984 
1985 	/* Update the Quad Enable bit. */
1986 	*sr2 |= SR2_QUAD_EN_BIT7;
1987 
1988 	ret = spi_nor_write_sr2(nor, sr2);
1989 	if (ret)
1990 		return ret;
1991 
1992 	sr2_written = *sr2;
1993 
1994 	/* Read back and check it. */
1995 	ret = spi_nor_read_sr2(nor, sr2);
1996 	if (ret)
1997 		return ret;
1998 
1999 	if (*sr2 != sr2_written) {
2000 		dev_dbg(nor->dev, "SR2: Read back test failed\n");
2001 		return -EIO;
2002 	}
2003 
2004 	return 0;
2005 }
2006 
2007 static const struct spi_nor_manufacturer *manufacturers[] = {
2008 	&spi_nor_atmel,
2009 	&spi_nor_eon,
2010 	&spi_nor_esmt,
2011 	&spi_nor_everspin,
2012 	&spi_nor_gigadevice,
2013 	&spi_nor_intel,
2014 	&spi_nor_issi,
2015 	&spi_nor_macronix,
2016 	&spi_nor_micron,
2017 	&spi_nor_st,
2018 	&spi_nor_spansion,
2019 	&spi_nor_sst,
2020 	&spi_nor_winbond,
2021 	&spi_nor_xmc,
2022 };
2023 
2024 static const struct flash_info spi_nor_generic_flash = {
2025 	.name = "spi-nor-generic",
2026 };
2027 
2028 static const struct flash_info *spi_nor_match_id(struct spi_nor *nor,
2029 						 const u8 *id)
2030 {
2031 	const struct flash_info *part;
2032 	unsigned int i, j;
2033 
2034 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
2035 		for (j = 0; j < manufacturers[i]->nparts; j++) {
2036 			part = &manufacturers[i]->parts[j];
2037 			if (part->id &&
2038 			    !memcmp(part->id->bytes, id, part->id->len)) {
2039 				nor->manufacturer = manufacturers[i];
2040 				return part;
2041 			}
2042 		}
2043 	}
2044 
2045 	return NULL;
2046 }
2047 
2048 static const struct flash_info *spi_nor_detect(struct spi_nor *nor)
2049 {
2050 	const struct flash_info *info;
2051 	u8 *id = nor->bouncebuf;
2052 	int ret;
2053 
2054 	ret = spi_nor_read_id(nor, 0, 0, id, nor->reg_proto);
2055 	if (ret) {
2056 		dev_dbg(nor->dev, "error %d reading JEDEC ID\n", ret);
2057 		return ERR_PTR(ret);
2058 	}
2059 
2060 	/* Cache the complete flash ID. */
2061 	nor->id = devm_kmemdup(nor->dev, id, SPI_NOR_MAX_ID_LEN, GFP_KERNEL);
2062 	if (!nor->id)
2063 		return ERR_PTR(-ENOMEM);
2064 
2065 	info = spi_nor_match_id(nor, id);
2066 
2067 	/* Fallback to a generic flash described only by its SFDP data. */
2068 	if (!info) {
2069 		ret = spi_nor_check_sfdp_signature(nor);
2070 		if (!ret)
2071 			info = &spi_nor_generic_flash;
2072 	}
2073 
2074 	if (!info) {
2075 		dev_err(nor->dev, "unrecognized JEDEC id bytes: %*ph\n",
2076 			SPI_NOR_MAX_ID_LEN, id);
2077 		return ERR_PTR(-ENODEV);
2078 	}
2079 	return info;
2080 }
2081 
2082 /*
2083  * On Octal DTR capable flashes, reads cannot start or end at an odd
2084  * address in Octal DTR mode. Extra bytes need to be read at the start
2085  * or end to make sure both the start address and length remain even.
2086  */
2087 static int spi_nor_octal_dtr_read(struct spi_nor *nor, loff_t from, size_t len,
2088 				  u_char *buf)
2089 {
2090 	u_char *tmp_buf;
2091 	size_t tmp_len;
2092 	loff_t start, end;
2093 	int ret, bytes_read;
2094 
2095 	if (IS_ALIGNED(from, 2) && IS_ALIGNED(len, 2))
2096 		return spi_nor_read_data(nor, from, len, buf);
2097 	else if (IS_ALIGNED(from, 2) && len > PAGE_SIZE)
2098 		return spi_nor_read_data(nor, from, round_down(len, PAGE_SIZE),
2099 					 buf);
2100 
2101 	tmp_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
2102 	if (!tmp_buf)
2103 		return -ENOMEM;
2104 
2105 	start = round_down(from, 2);
2106 	end = round_up(from + len, 2);
2107 
2108 	/*
2109 	 * Avoid allocating too much memory. The requested read length might be
2110 	 * quite large. Allocating a buffer just as large (slightly bigger, in
2111 	 * fact) would put unnecessary memory pressure on the system.
2112 	 *
2113 	 * For example if the read is from 3 to 1M, then this will read from 2
2114 	 * to 4098. The reads from 4098 to 1M will then not need a temporary
2115 	 * buffer so they can proceed as normal.
2116 	 */
2117 	tmp_len = min_t(size_t, end - start, PAGE_SIZE);
2118 
2119 	ret = spi_nor_read_data(nor, start, tmp_len, tmp_buf);
2120 	if (ret == 0) {
2121 		ret = -EIO;
2122 		goto out;
2123 	}
2124 	if (ret < 0)
2125 		goto out;
2126 
2127 	/*
2128 	 * More bytes are read than actually requested, but that number can't be
2129 	 * reported to the calling function or it will confuse its calculations.
2130 	 * Calculate how many of the _requested_ bytes were read.
2131 	 */
2132 	bytes_read = ret;
2133 
2134 	if (from != start)
2135 		ret -= from - start;
2136 
2137 	/*
2138 	 * Only account for extra bytes at the end if they were actually read.
2139 	 * For example, if the total length was truncated because of temporary
2140 	 * buffer size limit then the adjustment for the extra bytes at the end
2141 	 * is not needed.
2142 	 */
2143 	if (start + bytes_read == end)
2144 		ret -= end - (from + len);
2145 
2146 	memcpy(buf, tmp_buf + (from - start), ret);
2147 out:
2148 	kfree(tmp_buf);
2149 	return ret;
2150 }
2151 
2152 static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
2153 			size_t *retlen, u_char *buf)
2154 {
2155 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2156 	loff_t from_lock = from;
2157 	size_t len_lock = len;
2158 	ssize_t ret;
2159 
2160 	dev_dbg(nor->dev, "from 0x%08x, len %zd\n", (u32)from, len);
2161 
2162 	ret = spi_nor_prep_and_lock_rd(nor, from_lock, len_lock);
2163 	if (ret)
2164 		return ret;
2165 
2166 	while (len) {
2167 		loff_t addr = from;
2168 
2169 		if (nor->read_proto == SNOR_PROTO_8_8_8_DTR)
2170 			ret = spi_nor_octal_dtr_read(nor, addr, len, buf);
2171 		else
2172 			ret = spi_nor_read_data(nor, addr, len, buf);
2173 
2174 		if (ret == 0) {
2175 			/* We shouldn't see 0-length reads */
2176 			ret = -EIO;
2177 			goto read_err;
2178 		}
2179 		if (ret < 0)
2180 			goto read_err;
2181 
2182 		WARN_ON(ret > len);
2183 		*retlen += ret;
2184 		buf += ret;
2185 		from += ret;
2186 		len -= ret;
2187 	}
2188 	ret = 0;
2189 
2190 read_err:
2191 	spi_nor_unlock_and_unprep_rd(nor, from_lock, len_lock);
2192 
2193 	return ret;
2194 }
2195 
2196 /*
2197  * On Octal DTR capable flashes, writes cannot start or end at an odd address
2198  * in Octal DTR mode. Extra 0xff bytes need to be appended or prepended to
2199  * make sure the start address and end address are even. 0xff is used because
2200  * on NOR flashes a program operation can only flip bits from 1 to 0, not the
2201  * other way round. 0 to 1 flip needs to happen via erases.
2202  */
2203 static int spi_nor_octal_dtr_write(struct spi_nor *nor, loff_t to, size_t len,
2204 				   const u8 *buf)
2205 {
2206 	u8 *tmp_buf;
2207 	size_t bytes_written;
2208 	loff_t start, end;
2209 	int ret;
2210 
2211 	if (IS_ALIGNED(to, 2) && IS_ALIGNED(len, 2))
2212 		return spi_nor_write_data(nor, to, len, buf);
2213 
2214 	tmp_buf = kmalloc(nor->params->page_size, GFP_KERNEL);
2215 	if (!tmp_buf)
2216 		return -ENOMEM;
2217 
2218 	memset(tmp_buf, 0xff, nor->params->page_size);
2219 
2220 	start = round_down(to, 2);
2221 	end = round_up(to + len, 2);
2222 
2223 	memcpy(tmp_buf + (to - start), buf, len);
2224 
2225 	ret = spi_nor_write_data(nor, start, end - start, tmp_buf);
2226 	if (ret == 0) {
2227 		ret = -EIO;
2228 		goto out;
2229 	}
2230 	if (ret < 0)
2231 		goto out;
2232 
2233 	/*
2234 	 * More bytes are written than actually requested, but that number can't
2235 	 * be reported to the calling function or it will confuse its
2236 	 * calculations. Calculate how many of the _requested_ bytes were
2237 	 * written.
2238 	 */
2239 	bytes_written = ret;
2240 
2241 	if (to != start)
2242 		ret -= to - start;
2243 
2244 	/*
2245 	 * Only account for extra bytes at the end if they were actually
2246 	 * written. For example, if for some reason the controller could only
2247 	 * complete a partial write then the adjustment for the extra bytes at
2248 	 * the end is not needed.
2249 	 */
2250 	if (start + bytes_written == end)
2251 		ret -= end - (to + len);
2252 
2253 out:
2254 	kfree(tmp_buf);
2255 	return ret;
2256 }
2257 
2258 /*
2259  * Write an address range to the nor chip.  Data must be written in
2260  * FLASH_PAGESIZE chunks.  The address range may be any size provided
2261  * it is within the physical boundaries.
2262  */
2263 static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
2264 	size_t *retlen, const u_char *buf)
2265 {
2266 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2267 	size_t i;
2268 	ssize_t ret;
2269 	u32 page_size = nor->params->page_size;
2270 
2271 	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
2272 
2273 	ret = spi_nor_prep_and_lock_pe(nor, to, len);
2274 	if (ret)
2275 		return ret;
2276 
2277 	for (i = 0; i < len; ) {
2278 		ssize_t written;
2279 		loff_t addr = to + i;
2280 		size_t page_offset = addr & (page_size - 1);
2281 		/* the size of data remaining on the first page */
2282 		size_t page_remain = min_t(size_t, page_size - page_offset, len - i);
2283 
2284 		ret = spi_nor_lock_device(nor);
2285 		if (ret)
2286 			goto write_err;
2287 
2288 		ret = spi_nor_write_enable(nor);
2289 		if (ret) {
2290 			spi_nor_unlock_device(nor);
2291 			goto write_err;
2292 		}
2293 
2294 		if (nor->write_proto == SNOR_PROTO_8_8_8_DTR)
2295 			ret = spi_nor_octal_dtr_write(nor, addr, page_remain,
2296 						      buf + i);
2297 		else
2298 			ret = spi_nor_write_data(nor, addr, page_remain,
2299 						 buf + i);
2300 		spi_nor_unlock_device(nor);
2301 		if (ret < 0)
2302 			goto write_err;
2303 		written = ret;
2304 
2305 		ret = spi_nor_wait_till_ready(nor);
2306 		if (ret)
2307 			goto write_err;
2308 		*retlen += written;
2309 		i += written;
2310 	}
2311 
2312 write_err:
2313 	spi_nor_unlock_and_unprep_pe(nor, to, len);
2314 
2315 	return ret;
2316 }
2317 
2318 static int spi_nor_check(struct spi_nor *nor)
2319 {
2320 	if (!nor->dev ||
2321 	    (!nor->spimem && !nor->controller_ops) ||
2322 	    (!nor->spimem && nor->controller_ops &&
2323 	    (!nor->controller_ops->read ||
2324 	     !nor->controller_ops->write ||
2325 	     !nor->controller_ops->read_reg ||
2326 	     !nor->controller_ops->write_reg))) {
2327 		pr_err("spi-nor: please fill all the necessary fields!\n");
2328 		return -EINVAL;
2329 	}
2330 
2331 	if (nor->spimem && nor->controller_ops) {
2332 		dev_err(nor->dev, "nor->spimem and nor->controller_ops are mutually exclusive, please set just one of them.\n");
2333 		return -EINVAL;
2334 	}
2335 
2336 	return 0;
2337 }
2338 
2339 void
2340 spi_nor_set_read_settings(struct spi_nor_read_command *read,
2341 			  u8 num_mode_clocks,
2342 			  u8 num_wait_states,
2343 			  u8 opcode,
2344 			  enum spi_nor_protocol proto)
2345 {
2346 	read->num_mode_clocks = num_mode_clocks;
2347 	read->num_wait_states = num_wait_states;
2348 	read->opcode = opcode;
2349 	read->proto = proto;
2350 }
2351 
2352 void spi_nor_set_pp_settings(struct spi_nor_pp_command *pp, u8 opcode,
2353 			     enum spi_nor_protocol proto)
2354 {
2355 	pp->opcode = opcode;
2356 	pp->proto = proto;
2357 }
2358 
2359 static int spi_nor_hwcaps2cmd(u32 hwcaps, const int table[][2], size_t size)
2360 {
2361 	size_t i;
2362 
2363 	for (i = 0; i < size; i++)
2364 		if (table[i][0] == (int)hwcaps)
2365 			return table[i][1];
2366 
2367 	return -EINVAL;
2368 }
2369 
2370 int spi_nor_hwcaps_read2cmd(u32 hwcaps)
2371 {
2372 	static const int hwcaps_read2cmd[][2] = {
2373 		{ SNOR_HWCAPS_READ,		SNOR_CMD_READ },
2374 		{ SNOR_HWCAPS_READ_FAST,	SNOR_CMD_READ_FAST },
2375 		{ SNOR_HWCAPS_READ_1_1_1_DTR,	SNOR_CMD_READ_1_1_1_DTR },
2376 		{ SNOR_HWCAPS_READ_1_1_2,	SNOR_CMD_READ_1_1_2 },
2377 		{ SNOR_HWCAPS_READ_1_2_2,	SNOR_CMD_READ_1_2_2 },
2378 		{ SNOR_HWCAPS_READ_2_2_2,	SNOR_CMD_READ_2_2_2 },
2379 		{ SNOR_HWCAPS_READ_1_2_2_DTR,	SNOR_CMD_READ_1_2_2_DTR },
2380 		{ SNOR_HWCAPS_READ_1_1_4,	SNOR_CMD_READ_1_1_4 },
2381 		{ SNOR_HWCAPS_READ_1_4_4,	SNOR_CMD_READ_1_4_4 },
2382 		{ SNOR_HWCAPS_READ_4_4_4,	SNOR_CMD_READ_4_4_4 },
2383 		{ SNOR_HWCAPS_READ_1_4_4_DTR,	SNOR_CMD_READ_1_4_4_DTR },
2384 		{ SNOR_HWCAPS_READ_1_1_8,	SNOR_CMD_READ_1_1_8 },
2385 		{ SNOR_HWCAPS_READ_1_8_8,	SNOR_CMD_READ_1_8_8 },
2386 		{ SNOR_HWCAPS_READ_8_8_8,	SNOR_CMD_READ_8_8_8 },
2387 		{ SNOR_HWCAPS_READ_1_8_8_DTR,	SNOR_CMD_READ_1_8_8_DTR },
2388 		{ SNOR_HWCAPS_READ_8_8_8_DTR,	SNOR_CMD_READ_8_8_8_DTR },
2389 	};
2390 
2391 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_read2cmd,
2392 				  ARRAY_SIZE(hwcaps_read2cmd));
2393 }
2394 
2395 int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
2396 {
2397 	static const int hwcaps_pp2cmd[][2] = {
2398 		{ SNOR_HWCAPS_PP,		SNOR_CMD_PP },
2399 		{ SNOR_HWCAPS_PP_1_1_4,		SNOR_CMD_PP_1_1_4 },
2400 		{ SNOR_HWCAPS_PP_1_4_4,		SNOR_CMD_PP_1_4_4 },
2401 		{ SNOR_HWCAPS_PP_4_4_4,		SNOR_CMD_PP_4_4_4 },
2402 		{ SNOR_HWCAPS_PP_1_1_8,		SNOR_CMD_PP_1_1_8 },
2403 		{ SNOR_HWCAPS_PP_1_8_8,		SNOR_CMD_PP_1_8_8 },
2404 		{ SNOR_HWCAPS_PP_8_8_8,		SNOR_CMD_PP_8_8_8 },
2405 		{ SNOR_HWCAPS_PP_8_8_8_DTR,	SNOR_CMD_PP_8_8_8_DTR },
2406 	};
2407 
2408 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_pp2cmd,
2409 				  ARRAY_SIZE(hwcaps_pp2cmd));
2410 }
2411 
2412 /**
2413  * spi_nor_spimem_check_read_pp_op - check if a read or a page program operation is
2414  *                                   supported by controller
2415  *@nor:        pointer to a 'struct spi_nor'
2416  *@op:         pointer to op template to be checked
2417  *
2418  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2419  */
2420 static int spi_nor_spimem_check_read_pp_op(struct spi_nor *nor,
2421 					   struct spi_mem_op *op)
2422 {
2423 	/*
2424 	 * First test with 4 address bytes. The opcode itself might
2425 	 * be a 3B addressing opcode but we don't care, because
2426 	 * SPI controller implementation should not check the opcode,
2427 	 * but just the sequence.
2428 	 */
2429 	op->addr.nbytes = 4;
2430 	if (!spi_mem_supports_op(nor->spimem, op)) {
2431 		if (nor->params->size > SZ_16M)
2432 			return -EOPNOTSUPP;
2433 
2434 		/* If flash size <= 16MB, 3 address bytes are sufficient */
2435 		op->addr.nbytes = 3;
2436 		if (!spi_mem_supports_op(nor->spimem, op))
2437 			return -EOPNOTSUPP;
2438 	}
2439 
2440 	return 0;
2441 }
2442 
2443 /**
2444  * spi_nor_spimem_check_readop - check if the read op is supported
2445  *                               by controller
2446  *@nor:         pointer to a 'struct spi_nor'
2447  *@read:        pointer to op template to be checked
2448  *
2449  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2450  */
2451 static int spi_nor_spimem_check_readop(struct spi_nor *nor,
2452 				       const struct spi_nor_read_command *read)
2453 {
2454 	struct spi_mem_op op = SPI_NOR_READ_OP(read->opcode);
2455 
2456 	spi_nor_spimem_setup_op(nor, &op, read->proto);
2457 
2458 	/* convert the dummy cycles to the number of bytes */
2459 	op.dummy.nbytes = (read->num_mode_clocks + read->num_wait_states) *
2460 			  op.dummy.buswidth / 8;
2461 	if (spi_nor_protocol_is_dtr(read->proto))
2462 		op.dummy.nbytes *= 2;
2463 
2464 	return spi_nor_spimem_check_read_pp_op(nor, &op);
2465 }
2466 
2467 /**
2468  * spi_nor_spimem_check_pp - check if the page program op is supported
2469  *                           by controller
2470  *@nor:         pointer to a 'struct spi_nor'
2471  *@pp:          pointer to op template to be checked
2472  *
2473  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2474  */
2475 static int spi_nor_spimem_check_pp(struct spi_nor *nor,
2476 				   const struct spi_nor_pp_command *pp)
2477 {
2478 	struct spi_mem_op op = SPI_NOR_PP_OP(pp->opcode);
2479 
2480 	spi_nor_spimem_setup_op(nor, &op, pp->proto);
2481 
2482 	return spi_nor_spimem_check_read_pp_op(nor, &op);
2483 }
2484 
2485 /**
2486  * spi_nor_spimem_adjust_hwcaps - Find optimal Read/Write protocol
2487  *                                based on SPI controller capabilities
2488  * @nor:        pointer to a 'struct spi_nor'
2489  * @hwcaps:     pointer to resulting capabilities after adjusting
2490  *              according to controller and flash's capability
2491  */
2492 static void
2493 spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor, u32 *hwcaps)
2494 {
2495 	struct spi_nor_flash_parameter *params = nor->params;
2496 	unsigned int cap;
2497 
2498 	/* X-X-X modes are not supported yet, mask them all. */
2499 	*hwcaps &= ~SNOR_HWCAPS_X_X_X;
2500 
2501 	/*
2502 	 * If the reset line is broken, we do not want to enter a stateful
2503 	 * mode.
2504 	 */
2505 	if (nor->flags & SNOR_F_BROKEN_RESET)
2506 		*hwcaps &= ~(SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR);
2507 
2508 	for (cap = 0; cap < sizeof(*hwcaps) * BITS_PER_BYTE; cap++) {
2509 		int rdidx, ppidx;
2510 
2511 		if (!(*hwcaps & BIT(cap)))
2512 			continue;
2513 
2514 		rdidx = spi_nor_hwcaps_read2cmd(BIT(cap));
2515 		if (rdidx >= 0 &&
2516 		    spi_nor_spimem_check_readop(nor, &params->reads[rdidx]))
2517 			*hwcaps &= ~BIT(cap);
2518 
2519 		ppidx = spi_nor_hwcaps_pp2cmd(BIT(cap));
2520 		if (ppidx < 0)
2521 			continue;
2522 
2523 		if (spi_nor_spimem_check_pp(nor,
2524 					    &params->page_programs[ppidx]))
2525 			*hwcaps &= ~BIT(cap);
2526 	}
2527 
2528 	/* Some SPI controllers might not support CR read opcode. */
2529 	if (!(nor->flags & SNOR_F_NO_READ_CR)) {
2530 		struct spi_mem_op op = SPI_NOR_RDCR_OP(nor->bouncebuf);
2531 
2532 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
2533 
2534 		if (!spi_mem_supports_op(nor->spimem, &op))
2535 			nor->flags |= SNOR_F_NO_READ_CR;
2536 	}
2537 }
2538 
2539 /**
2540  * spi_nor_set_erase_type() - set a SPI NOR erase type
2541  * @erase:	pointer to a structure that describes a SPI NOR erase type
2542  * @size:	the size of the sector/block erased by the erase type
2543  * @opcode:	the SPI command op code to erase the sector/block
2544  */
2545 void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
2546 			    u8 opcode)
2547 {
2548 	erase->size = size;
2549 	erase->opcode = opcode;
2550 	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
2551 	erase->size_shift = ffs(erase->size) - 1;
2552 	erase->size_mask = (1 << erase->size_shift) - 1;
2553 }
2554 
2555 /**
2556  * spi_nor_mask_erase_type() - mask out a SPI NOR erase type
2557  * @erase:	pointer to a structure that describes a SPI NOR erase type
2558  */
2559 void spi_nor_mask_erase_type(struct spi_nor_erase_type *erase)
2560 {
2561 	erase->size = 0;
2562 }
2563 
2564 /**
2565  * spi_nor_init_uniform_erase_map() - Initialize uniform erase map
2566  * @map:		the erase map of the SPI NOR
2567  * @erase_mask:		bitmask encoding erase types that can erase the entire
2568  *			flash memory
2569  * @flash_size:		the spi nor flash memory size
2570  */
2571 void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
2572 				    u8 erase_mask, u64 flash_size)
2573 {
2574 	map->uniform_region.offset = 0;
2575 	map->uniform_region.size = flash_size;
2576 	map->uniform_region.erase_mask = erase_mask;
2577 	map->regions = &map->uniform_region;
2578 	map->n_regions = 1;
2579 }
2580 
2581 int spi_nor_post_bfpt_fixups(struct spi_nor *nor,
2582 			     const struct sfdp_parameter_header *bfpt_header,
2583 			     const struct sfdp_bfpt *bfpt)
2584 {
2585 	int ret;
2586 
2587 	if (nor->manufacturer && nor->manufacturer->fixups &&
2588 	    nor->manufacturer->fixups->post_bfpt) {
2589 		ret = nor->manufacturer->fixups->post_bfpt(nor, bfpt_header,
2590 							   bfpt);
2591 		if (ret)
2592 			return ret;
2593 	}
2594 
2595 	if (nor->info->fixups && nor->info->fixups->post_bfpt)
2596 		return nor->info->fixups->post_bfpt(nor, bfpt_header, bfpt);
2597 
2598 	return 0;
2599 }
2600 
2601 static int spi_nor_select_read(struct spi_nor *nor,
2602 			       u32 shared_hwcaps)
2603 {
2604 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_READ_MASK) - 1;
2605 	const struct spi_nor_read_command *read;
2606 
2607 	if (best_match < 0)
2608 		return -EINVAL;
2609 
2610 	cmd = spi_nor_hwcaps_read2cmd(BIT(best_match));
2611 	if (cmd < 0)
2612 		return -EINVAL;
2613 
2614 	read = &nor->params->reads[cmd];
2615 	nor->read_opcode = read->opcode;
2616 	nor->read_proto = read->proto;
2617 
2618 	/*
2619 	 * In the SPI NOR framework, we don't need to make the difference
2620 	 * between mode clock cycles and wait state clock cycles.
2621 	 * Indeed, the value of the mode clock cycles is used by a QSPI
2622 	 * flash memory to know whether it should enter or leave its 0-4-4
2623 	 * (Continuous Read / XIP) mode.
2624 	 * eXecution In Place is out of the scope of the mtd sub-system.
2625 	 * Hence we choose to merge both mode and wait state clock cycles
2626 	 * into the so called dummy clock cycles.
2627 	 */
2628 	nor->read_dummy = read->num_mode_clocks + read->num_wait_states;
2629 	return 0;
2630 }
2631 
2632 static int spi_nor_select_pp(struct spi_nor *nor,
2633 			     u32 shared_hwcaps)
2634 {
2635 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_PP_MASK) - 1;
2636 	const struct spi_nor_pp_command *pp;
2637 
2638 	if (best_match < 0)
2639 		return -EINVAL;
2640 
2641 	cmd = spi_nor_hwcaps_pp2cmd(BIT(best_match));
2642 	if (cmd < 0)
2643 		return -EINVAL;
2644 
2645 	pp = &nor->params->page_programs[cmd];
2646 	nor->program_opcode = pp->opcode;
2647 	nor->write_proto = pp->proto;
2648 	return 0;
2649 }
2650 
2651 /**
2652  * spi_nor_select_uniform_erase() - select optimum uniform erase type
2653  * @map:		the erase map of the SPI NOR
2654  *
2655  * Once the optimum uniform sector erase command is found, disable all the
2656  * other.
2657  *
2658  * Return: pointer to erase type on success, NULL otherwise.
2659  */
2660 static const struct spi_nor_erase_type *
2661 spi_nor_select_uniform_erase(struct spi_nor_erase_map *map)
2662 {
2663 	const struct spi_nor_erase_type *tested_erase, *erase = NULL;
2664 	int i;
2665 	u8 uniform_erase_type = map->uniform_region.erase_mask;
2666 
2667 	/*
2668 	 * Search for the biggest erase size, except for when compiled
2669 	 * to use 4k erases.
2670 	 */
2671 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2672 		if (!(uniform_erase_type & BIT(i)))
2673 			continue;
2674 
2675 		tested_erase = &map->erase_type[i];
2676 
2677 		/* Skip masked erase types. */
2678 		if (!tested_erase->size)
2679 			continue;
2680 
2681 		/*
2682 		 * If the current erase size is the 4k one, stop here,
2683 		 * we have found the right uniform Sector Erase command.
2684 		 */
2685 		if (IS_ENABLED(CONFIG_MTD_SPI_NOR_USE_4K_SECTORS) &&
2686 		    tested_erase->size == SZ_4K) {
2687 			erase = tested_erase;
2688 			break;
2689 		}
2690 
2691 		/*
2692 		 * Otherwise, the current erase size is still a valid candidate.
2693 		 * Select the biggest valid candidate.
2694 		 */
2695 		if (!erase && tested_erase->size)
2696 			erase = tested_erase;
2697 			/* keep iterating to find the wanted_size */
2698 	}
2699 
2700 	if (!erase)
2701 		return NULL;
2702 
2703 	/* Disable all other Sector Erase commands. */
2704 	map->uniform_region.erase_mask = BIT(erase - map->erase_type);
2705 	return erase;
2706 }
2707 
2708 static int spi_nor_select_erase(struct spi_nor *nor)
2709 {
2710 	struct spi_nor_erase_map *map = &nor->params->erase_map;
2711 	const struct spi_nor_erase_type *erase = NULL;
2712 	struct mtd_info *mtd = &nor->mtd;
2713 	int i;
2714 
2715 	/*
2716 	 * The previous implementation handling Sector Erase commands assumed
2717 	 * that the SPI flash memory has an uniform layout then used only one
2718 	 * of the supported erase sizes for all Sector Erase commands.
2719 	 * So to be backward compatible, the new implementation also tries to
2720 	 * manage the SPI flash memory as uniform with a single erase sector
2721 	 * size, when possible.
2722 	 */
2723 	if (spi_nor_has_uniform_erase(nor)) {
2724 		erase = spi_nor_select_uniform_erase(map);
2725 		if (!erase)
2726 			return -EINVAL;
2727 		nor->erase_opcode = erase->opcode;
2728 		mtd->erasesize = erase->size;
2729 		return 0;
2730 	}
2731 
2732 	/*
2733 	 * For non-uniform SPI flash memory, set mtd->erasesize to the
2734 	 * maximum erase sector size. No need to set nor->erase_opcode.
2735 	 */
2736 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2737 		if (map->erase_type[i].size) {
2738 			erase = &map->erase_type[i];
2739 			break;
2740 		}
2741 	}
2742 
2743 	if (!erase)
2744 		return -EINVAL;
2745 
2746 	mtd->erasesize = erase->size;
2747 	return 0;
2748 }
2749 
2750 static int spi_nor_set_addr_nbytes(struct spi_nor *nor)
2751 {
2752 	if (nor->params->addr_nbytes) {
2753 		nor->addr_nbytes = nor->params->addr_nbytes;
2754 	} else if (nor->read_proto == SNOR_PROTO_8_8_8_DTR) {
2755 		/*
2756 		 * In 8D-8D-8D mode, one byte takes half a cycle to transfer. So
2757 		 * in this protocol an odd addr_nbytes cannot be used because
2758 		 * then the address phase would only span a cycle and a half.
2759 		 * Half a cycle would be left over. We would then have to start
2760 		 * the dummy phase in the middle of a cycle and so too the data
2761 		 * phase, and we will end the transaction with half a cycle left
2762 		 * over.
2763 		 *
2764 		 * Force all 8D-8D-8D flashes to use an addr_nbytes of 4 to
2765 		 * avoid this situation.
2766 		 */
2767 		nor->addr_nbytes = 4;
2768 	} else if (nor->info->addr_nbytes) {
2769 		nor->addr_nbytes = nor->info->addr_nbytes;
2770 	} else {
2771 		nor->addr_nbytes = 3;
2772 	}
2773 
2774 	if (nor->addr_nbytes == 3 && nor->params->size > 0x1000000) {
2775 		/* enable 4-byte addressing if the device exceeds 16MiB */
2776 		nor->addr_nbytes = 4;
2777 	}
2778 
2779 	if (nor->addr_nbytes > SPI_NOR_MAX_ADDR_NBYTES) {
2780 		dev_dbg(nor->dev, "The number of address bytes is too large: %u\n",
2781 			nor->addr_nbytes);
2782 		return -EINVAL;
2783 	}
2784 
2785 	/* Set 4byte opcodes when possible. */
2786 	if (nor->addr_nbytes == 4 && nor->flags & SNOR_F_4B_OPCODES &&
2787 	    !(nor->flags & SNOR_F_HAS_4BAIT))
2788 		spi_nor_set_4byte_opcodes(nor);
2789 
2790 	return 0;
2791 }
2792 
2793 static int spi_nor_setup(struct spi_nor *nor,
2794 			 const struct spi_nor_hwcaps *hwcaps)
2795 {
2796 	struct spi_nor_flash_parameter *params = nor->params;
2797 	u32 ignored_mask, shared_mask;
2798 	int err;
2799 
2800 	/*
2801 	 * Keep only the hardware capabilities supported by both the SPI
2802 	 * controller and the SPI flash memory.
2803 	 */
2804 	shared_mask = hwcaps->mask & params->hwcaps.mask;
2805 
2806 	if (nor->spimem) {
2807 		/*
2808 		 * When called from spi_nor_probe(), all caps are set and we
2809 		 * need to discard some of them based on what the SPI
2810 		 * controller actually supports (using spi_mem_supports_op()).
2811 		 */
2812 		spi_nor_spimem_adjust_hwcaps(nor, &shared_mask);
2813 	} else {
2814 		/*
2815 		 * SPI n-n-n protocols are not supported when the SPI
2816 		 * controller directly implements the spi_nor interface.
2817 		 * Yet another reason to switch to spi-mem.
2818 		 */
2819 		ignored_mask = SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR;
2820 		if (shared_mask & ignored_mask) {
2821 			dev_dbg(nor->dev,
2822 				"SPI n-n-n protocols are not supported.\n");
2823 			shared_mask &= ~ignored_mask;
2824 		}
2825 	}
2826 
2827 	/* Select the (Fast) Read command. */
2828 	err = spi_nor_select_read(nor, shared_mask);
2829 	if (err) {
2830 		dev_dbg(nor->dev,
2831 			"can't select read settings supported by both the SPI controller and memory.\n");
2832 		return err;
2833 	}
2834 
2835 	/* Select the Page Program command. */
2836 	err = spi_nor_select_pp(nor, shared_mask);
2837 	if (err) {
2838 		dev_dbg(nor->dev,
2839 			"can't select write settings supported by both the SPI controller and memory.\n");
2840 		return err;
2841 	}
2842 
2843 	/* Select the Sector Erase command. */
2844 	err = spi_nor_select_erase(nor);
2845 	if (err) {
2846 		dev_dbg(nor->dev,
2847 			"can't select erase settings supported by both the SPI controller and memory.\n");
2848 		return err;
2849 	}
2850 
2851 	return spi_nor_set_addr_nbytes(nor);
2852 }
2853 
2854 /**
2855  * spi_nor_manufacturer_init_params() - Initialize the flash's parameters and
2856  * settings based on MFR register and ->default_init() hook.
2857  * @nor:	pointer to a 'struct spi_nor'.
2858  */
2859 static void spi_nor_manufacturer_init_params(struct spi_nor *nor)
2860 {
2861 	if (nor->manufacturer && nor->manufacturer->fixups &&
2862 	    nor->manufacturer->fixups->default_init)
2863 		nor->manufacturer->fixups->default_init(nor);
2864 
2865 	if (nor->info->fixups && nor->info->fixups->default_init)
2866 		nor->info->fixups->default_init(nor);
2867 }
2868 
2869 /**
2870  * spi_nor_no_sfdp_init_params() - Initialize the flash's parameters and
2871  * settings based on nor->info->sfdp_flags. This method should be called only by
2872  * flashes that do not define SFDP tables. If the flash supports SFDP but the
2873  * information is wrong and the settings from this function can not be retrieved
2874  * by parsing SFDP, one should instead use the fixup hooks and update the wrong
2875  * bits.
2876  * @nor:	pointer to a 'struct spi_nor'.
2877  */
2878 static void spi_nor_no_sfdp_init_params(struct spi_nor *nor)
2879 {
2880 	struct spi_nor_flash_parameter *params = nor->params;
2881 	struct spi_nor_erase_map *map = &params->erase_map;
2882 	const struct flash_info *info = nor->info;
2883 	const u8 no_sfdp_flags = info->no_sfdp_flags;
2884 	u8 i, erase_mask;
2885 
2886 	if (no_sfdp_flags & SPI_NOR_DUAL_READ) {
2887 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
2888 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_2],
2889 					  0, 8, SPINOR_OP_READ_1_1_2,
2890 					  SNOR_PROTO_1_1_2);
2891 	}
2892 
2893 	if (no_sfdp_flags & SPI_NOR_QUAD_READ) {
2894 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
2895 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_4],
2896 					  0, 8, SPINOR_OP_READ_1_1_4,
2897 					  SNOR_PROTO_1_1_4);
2898 	}
2899 
2900 	if (no_sfdp_flags & SPI_NOR_OCTAL_READ) {
2901 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
2902 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
2903 					  0, 8, SPINOR_OP_READ_1_1_8,
2904 					  SNOR_PROTO_1_1_8);
2905 	}
2906 
2907 	if (no_sfdp_flags & SPI_NOR_OCTAL_DTR_READ) {
2908 		params->hwcaps.mask |= SNOR_HWCAPS_READ_8_8_8_DTR;
2909 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_8_8_8_DTR],
2910 					  0, 20, SPINOR_OP_READ_FAST,
2911 					  SNOR_PROTO_8_8_8_DTR);
2912 	}
2913 
2914 	if (no_sfdp_flags & SPI_NOR_OCTAL_DTR_PP) {
2915 		params->hwcaps.mask |= SNOR_HWCAPS_PP_8_8_8_DTR;
2916 		/*
2917 		 * Since xSPI Page Program opcode is backward compatible with
2918 		 * Legacy SPI, use Legacy SPI opcode there as well.
2919 		 */
2920 		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_8_8_8_DTR],
2921 					SPINOR_OP_PP, SNOR_PROTO_8_8_8_DTR);
2922 	}
2923 
2924 	/*
2925 	 * Sector Erase settings. Sort Erase Types in ascending order, with the
2926 	 * smallest erase size starting at BIT(0).
2927 	 */
2928 	erase_mask = 0;
2929 	i = 0;
2930 	if (no_sfdp_flags & SECT_4K) {
2931 		erase_mask |= BIT(i);
2932 		spi_nor_set_erase_type(&map->erase_type[i], 4096u,
2933 				       SPINOR_OP_BE_4K);
2934 		i++;
2935 	}
2936 	erase_mask |= BIT(i);
2937 	spi_nor_set_erase_type(&map->erase_type[i],
2938 			       info->sector_size ?: SPI_NOR_DEFAULT_SECTOR_SIZE,
2939 			       SPINOR_OP_SE);
2940 	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
2941 }
2942 
2943 /**
2944  * spi_nor_init_flags() - Initialize NOR flags for settings that are not defined
2945  * in the JESD216 SFDP standard, thus can not be retrieved when parsing SFDP.
2946  * @nor:	pointer to a 'struct spi_nor'
2947  */
2948 static void spi_nor_init_flags(struct spi_nor *nor)
2949 {
2950 	struct device_node *np = spi_nor_get_flash_node(nor);
2951 	const u16 flags = nor->info->flags;
2952 
2953 	if (of_property_read_bool(np, "broken-flash-reset"))
2954 		nor->flags |= SNOR_F_BROKEN_RESET;
2955 
2956 	if (of_property_read_bool(np, "no-wp"))
2957 		nor->flags |= SNOR_F_NO_WP;
2958 
2959 	if (flags & SPI_NOR_SWP_IS_VOLATILE)
2960 		nor->flags |= SNOR_F_SWP_IS_VOLATILE;
2961 
2962 	if (flags & SPI_NOR_HAS_LOCK)
2963 		nor->flags |= SNOR_F_HAS_LOCK;
2964 
2965 	if (flags & SPI_NOR_HAS_TB) {
2966 		nor->flags |= SNOR_F_HAS_SR_TB;
2967 		if (flags & SPI_NOR_TB_SR_BIT6)
2968 			nor->flags |= SNOR_F_HAS_SR_TB_BIT6;
2969 	}
2970 
2971 	if (flags & SPI_NOR_4BIT_BP) {
2972 		nor->flags |= SNOR_F_HAS_4BIT_BP;
2973 		if (flags & SPI_NOR_BP3_SR_BIT6)
2974 			nor->flags |= SNOR_F_HAS_SR_BP3_BIT6;
2975 	}
2976 
2977 	if (flags & SPI_NOR_HAS_CMP)
2978 		nor->flags |= SNOR_F_HAS_SR2_CMP_BIT6;
2979 
2980 	if (flags & SPI_NOR_RWW && nor->params->n_banks > 1 &&
2981 	    !nor->controller_ops)
2982 		nor->flags |= SNOR_F_RWW;
2983 }
2984 
2985 /**
2986  * spi_nor_init_fixup_flags() - Initialize NOR flags for settings that can not
2987  * be discovered by SFDP for this particular flash because the SFDP table that
2988  * indicates this support is not defined in the flash. In case the table for
2989  * this support is defined but has wrong values, one should instead use a
2990  * post_sfdp() hook to set the SNOR_F equivalent flag.
2991  * @nor:       pointer to a 'struct spi_nor'
2992  */
2993 static void spi_nor_init_fixup_flags(struct spi_nor *nor)
2994 {
2995 	const u8 fixup_flags = nor->info->fixup_flags;
2996 
2997 	if (fixup_flags & SPI_NOR_4B_OPCODES)
2998 		nor->flags |= SNOR_F_4B_OPCODES;
2999 
3000 	if (fixup_flags & SPI_NOR_IO_MODE_EN_VOLATILE)
3001 		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;
3002 }
3003 
3004 /**
3005  * spi_nor_late_init_params() - Late initialization of default flash parameters.
3006  * @nor:	pointer to a 'struct spi_nor'
3007  *
3008  * Used to initialize flash parameters that are not declared in the JESD216
3009  * SFDP standard, or where SFDP tables are not defined at all.
3010  * Will replace the spi_nor_manufacturer_init_params() method.
3011  */
3012 static int spi_nor_late_init_params(struct spi_nor *nor)
3013 {
3014 	struct spi_nor_flash_parameter *params = nor->params;
3015 	int ret;
3016 
3017 	if (nor->manufacturer && nor->manufacturer->fixups &&
3018 	    nor->manufacturer->fixups->late_init) {
3019 		ret = nor->manufacturer->fixups->late_init(nor);
3020 		if (ret)
3021 			return ret;
3022 	}
3023 
3024 	/* Needed by some flashes late_init hooks. */
3025 	spi_nor_init_flags(nor);
3026 
3027 	if (nor->info->fixups && nor->info->fixups->late_init) {
3028 		ret = nor->info->fixups->late_init(nor);
3029 		if (ret)
3030 			return ret;
3031 	}
3032 
3033 	if (!nor->params->die_erase_opcode)
3034 		nor->params->die_erase_opcode = SPINOR_OP_CHIP_ERASE;
3035 
3036 	/* Default method kept for backward compatibility. */
3037 	if (!params->set_4byte_addr_mode)
3038 		params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_brwr;
3039 
3040 	spi_nor_init_fixup_flags(nor);
3041 
3042 	/*
3043 	 * NOR protection support. When locking_ops are not provided, we pick
3044 	 * the default ones.
3045 	 */
3046 	if (nor->flags & SNOR_F_HAS_LOCK && !nor->params->locking_ops)
3047 		spi_nor_init_default_locking_ops(nor);
3048 
3049 	if (params->n_banks > 1)
3050 		params->bank_size = div_u64(params->size, params->n_banks);
3051 
3052 	return 0;
3053 }
3054 
3055 /**
3056  * spi_nor_sfdp_init_params_deprecated() - Deprecated way of initializing flash
3057  * parameters and settings based on JESD216 SFDP standard.
3058  * @nor:	pointer to a 'struct spi_nor'.
3059  *
3060  * The method has a roll-back mechanism: in case the SFDP parsing fails, the
3061  * legacy flash parameters and settings will be restored.
3062  */
3063 static void spi_nor_sfdp_init_params_deprecated(struct spi_nor *nor)
3064 {
3065 	struct spi_nor_flash_parameter sfdp_params;
3066 
3067 	memcpy(&sfdp_params, nor->params, sizeof(sfdp_params));
3068 
3069 	if (spi_nor_parse_sfdp(nor)) {
3070 		memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
3071 		nor->flags &= ~SNOR_F_4B_OPCODES;
3072 	}
3073 }
3074 
3075 /**
3076  * spi_nor_init_params_deprecated() - Deprecated way of initializing flash
3077  * parameters and settings.
3078  * @nor:	pointer to a 'struct spi_nor'.
3079  *
3080  * The method assumes that flash doesn't support SFDP so it initializes flash
3081  * parameters in spi_nor_no_sfdp_init_params() which later on can be overwritten
3082  * when parsing SFDP, if supported.
3083  */
3084 static void spi_nor_init_params_deprecated(struct spi_nor *nor)
3085 {
3086 	spi_nor_no_sfdp_init_params(nor);
3087 
3088 	spi_nor_manufacturer_init_params(nor);
3089 
3090 	if (nor->info->no_sfdp_flags & (SPI_NOR_DUAL_READ |
3091 					SPI_NOR_QUAD_READ |
3092 					SPI_NOR_OCTAL_READ |
3093 					SPI_NOR_OCTAL_DTR_READ))
3094 		spi_nor_sfdp_init_params_deprecated(nor);
3095 }
3096 
3097 /**
3098  * spi_nor_init_default_params() - Default initialization of flash parameters
3099  * and settings. Done for all flashes, regardless is they define SFDP tables
3100  * or not.
3101  * @nor:	pointer to a 'struct spi_nor'.
3102  */
3103 static void spi_nor_init_default_params(struct spi_nor *nor)
3104 {
3105 	struct spi_nor_flash_parameter *params = nor->params;
3106 	const struct flash_info *info = nor->info;
3107 	struct device_node *np = spi_nor_get_flash_node(nor);
3108 
3109 	params->quad_enable = spi_nor_sr2_bit1_quad_enable;
3110 	params->otp.org = info->otp;
3111 
3112 	/* Default to 16-bit Write Status (01h) Command */
3113 	nor->flags |= SNOR_F_HAS_16BIT_SR;
3114 
3115 	/* Set SPI NOR sizes. */
3116 	params->writesize = 1;
3117 	params->size = info->size;
3118 	params->bank_size = params->size;
3119 	params->page_size = info->page_size ?: SPI_NOR_DEFAULT_PAGE_SIZE;
3120 	params->n_banks = info->n_banks ?: SPI_NOR_DEFAULT_N_BANKS;
3121 
3122 	/* Default to Fast Read for non-DT and enable it if requested by DT. */
3123 	if (!np || of_property_read_bool(np, "m25p,fast-read"))
3124 		params->hwcaps.mask |= SNOR_HWCAPS_READ_FAST;
3125 
3126 	/* (Fast) Read settings. */
3127 	params->hwcaps.mask |= SNOR_HWCAPS_READ;
3128 	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ],
3129 				  0, 0, SPINOR_OP_READ,
3130 				  SNOR_PROTO_1_1_1);
3131 
3132 	if (params->hwcaps.mask & SNOR_HWCAPS_READ_FAST)
3133 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_FAST],
3134 					  0, 8, SPINOR_OP_READ_FAST,
3135 					  SNOR_PROTO_1_1_1);
3136 	/* Page Program settings. */
3137 	params->hwcaps.mask |= SNOR_HWCAPS_PP;
3138 	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP],
3139 				SPINOR_OP_PP, SNOR_PROTO_1_1_1);
3140 
3141 	if (info->flags & SPI_NOR_QUAD_PP) {
3142 		params->hwcaps.mask |= SNOR_HWCAPS_PP_1_1_4;
3143 		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_1_1_4],
3144 					SPINOR_OP_PP_1_1_4, SNOR_PROTO_1_1_4);
3145 	}
3146 }
3147 
3148 /**
3149  * spi_nor_init_params() - Initialize the flash's parameters and settings.
3150  * @nor:	pointer to a 'struct spi_nor'.
3151  *
3152  * The flash parameters and settings are initialized based on a sequence of
3153  * calls that are ordered by priority:
3154  *
3155  * 1/ Default flash parameters initialization. The initializations are done
3156  *    based on nor->info data:
3157  *		spi_nor_info_init_params()
3158  *
3159  * which can be overwritten by:
3160  * 2/ Manufacturer flash parameters initialization. The initializations are
3161  *    done based on MFR register, or when the decisions can not be done solely
3162  *    based on MFR, by using specific flash_info tweeks, ->default_init():
3163  *		spi_nor_manufacturer_init_params()
3164  *
3165  * which can be overwritten by:
3166  * 3/ SFDP flash parameters initialization. JESD216 SFDP is a standard and
3167  *    should be more accurate that the above.
3168  *		spi_nor_parse_sfdp() or spi_nor_no_sfdp_init_params()
3169  *
3170  *    Please note that there is a ->post_bfpt() fixup hook that can overwrite
3171  *    the flash parameters and settings immediately after parsing the Basic
3172  *    Flash Parameter Table.
3173  *    spi_nor_post_sfdp_fixups() is called after the SFDP tables are parsed.
3174  *    It is used to tweak various flash parameters when information provided
3175  *    by the SFDP tables are wrong.
3176  *
3177  * which can be overwritten by:
3178  * 4/ Late flash parameters initialization, used to initialize flash
3179  * parameters that are not declared in the JESD216 SFDP standard, or where SFDP
3180  * tables are not defined at all.
3181  *		spi_nor_late_init_params()
3182  *
3183  * Return: 0 on success, -errno otherwise.
3184  */
3185 static int spi_nor_init_params(struct spi_nor *nor)
3186 {
3187 	int ret;
3188 
3189 	nor->params = devm_kzalloc(nor->dev, sizeof(*nor->params), GFP_KERNEL);
3190 	if (!nor->params)
3191 		return -ENOMEM;
3192 
3193 	spi_nor_init_default_params(nor);
3194 
3195 	if (spi_nor_needs_sfdp(nor)) {
3196 		ret = spi_nor_parse_sfdp(nor);
3197 		if (ret) {
3198 			dev_err(nor->dev, "BFPT parsing failed. Please consider using SPI_NOR_SKIP_SFDP when declaring the flash\n");
3199 			return ret;
3200 		}
3201 	} else if (nor->info->no_sfdp_flags & SPI_NOR_SKIP_SFDP) {
3202 		spi_nor_no_sfdp_init_params(nor);
3203 	} else {
3204 		spi_nor_init_params_deprecated(nor);
3205 	}
3206 
3207 	ret = spi_nor_late_init_params(nor);
3208 	if (ret)
3209 		return ret;
3210 
3211 	if (WARN_ON(!is_power_of_2(nor->params->page_size)))
3212 		return -EINVAL;
3213 
3214 	return 0;
3215 }
3216 
3217 /** spi_nor_set_octal_dtr() - enable or disable Octal DTR I/O.
3218  * @nor:                 pointer to a 'struct spi_nor'
3219  * @enable:              whether to enable or disable Octal DTR
3220  *
3221  * Return: 0 on success, -errno otherwise.
3222  */
3223 static int spi_nor_set_octal_dtr(struct spi_nor *nor, bool enable)
3224 {
3225 	int ret;
3226 
3227 	if (!nor->params->set_octal_dtr)
3228 		return 0;
3229 
3230 	if (!(nor->read_proto == SNOR_PROTO_8_8_8_DTR &&
3231 	      nor->write_proto == SNOR_PROTO_8_8_8_DTR))
3232 		return 0;
3233 
3234 	if (!(nor->flags & SNOR_F_IO_MODE_EN_VOLATILE))
3235 		return 0;
3236 
3237 	ret = nor->params->set_octal_dtr(nor, enable);
3238 	if (ret)
3239 		return ret;
3240 
3241 	if (enable)
3242 		nor->reg_proto = SNOR_PROTO_8_8_8_DTR;
3243 	else
3244 		nor->reg_proto = SNOR_PROTO_1_1_1;
3245 
3246 	return 0;
3247 }
3248 
3249 /**
3250  * spi_nor_quad_enable() - enable Quad I/O if needed.
3251  * @nor:                pointer to a 'struct spi_nor'
3252  *
3253  * Return: 0 on success, -errno otherwise.
3254  */
3255 static int spi_nor_quad_enable(struct spi_nor *nor)
3256 {
3257 	if (!nor->params->quad_enable)
3258 		return 0;
3259 
3260 	if (!(spi_nor_get_protocol_width(nor->read_proto) == 4 ||
3261 	      spi_nor_get_protocol_width(nor->write_proto) == 4))
3262 		return 0;
3263 
3264 	return nor->params->quad_enable(nor);
3265 }
3266 
3267 /**
3268  * spi_nor_set_4byte_addr_mode() - Set address mode.
3269  * @nor:                pointer to a 'struct spi_nor'.
3270  * @enable:             enable/disable 4 byte address mode.
3271  *
3272  * Return: 0 on success, -errno otherwise.
3273  */
3274 int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
3275 {
3276 	struct spi_nor_flash_parameter *params = nor->params;
3277 	int ret;
3278 
3279 	if (enable) {
3280 		/*
3281 		 * If the RESET# pin isn't hooked up properly, or the system
3282 		 * otherwise doesn't perform a reset command in the boot
3283 		 * sequence, it's impossible to 100% protect against unexpected
3284 		 * reboots (e.g., crashes). Warn the user (or hopefully, system
3285 		 * designer) that this is bad.
3286 		 */
3287 		WARN_ONCE(nor->flags & SNOR_F_BROKEN_RESET,
3288 			  "enabling reset hack; may not recover from unexpected reboots\n");
3289 	}
3290 
3291 	ret = params->set_4byte_addr_mode(nor, enable);
3292 	if (ret && ret != -EOPNOTSUPP)
3293 		return ret;
3294 
3295 	if (enable) {
3296 		params->addr_nbytes = 4;
3297 		params->addr_mode_nbytes = 4;
3298 	} else {
3299 		params->addr_nbytes = 3;
3300 		params->addr_mode_nbytes = 3;
3301 	}
3302 
3303 	return 0;
3304 }
3305 
3306 static int spi_nor_init(struct spi_nor *nor)
3307 {
3308 	int err;
3309 
3310 	err = spi_nor_set_octal_dtr(nor, true);
3311 	if (err) {
3312 		dev_dbg(nor->dev, "octal mode not supported\n");
3313 		return err;
3314 	}
3315 
3316 	err = spi_nor_quad_enable(nor);
3317 	if (err) {
3318 		dev_dbg(nor->dev, "quad mode not supported\n");
3319 		return err;
3320 	}
3321 
3322 	/*
3323 	 * Some SPI NOR flashes are write protected by default after a power-on
3324 	 * reset cycle, in order to avoid inadvertent writes during power-up.
3325 	 * Backward compatibility imposes to unlock the entire flash memory
3326 	 * array at power-up by default. Depending on the kernel configuration
3327 	 * (1) do nothing, (2) always unlock the entire flash array or (3)
3328 	 * unlock the entire flash array only when the software write
3329 	 * protection bits are volatile. The latter is indicated by
3330 	 * SNOR_F_SWP_IS_VOLATILE.
3331 	 */
3332 	spi_nor_cache_sr_lock_bits(nor, NULL);
3333 	if (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE) ||
3334 	    (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE_ON_VOLATILE) &&
3335 	     nor->flags & SNOR_F_SWP_IS_VOLATILE)) {
3336 		spi_nor_try_unlock_all(nor);
3337 	}
3338 
3339 	if (nor->addr_nbytes == 4 &&
3340 	    nor->read_proto != SNOR_PROTO_8_8_8_DTR &&
3341 	    !(nor->flags & SNOR_F_4B_OPCODES))
3342 		return spi_nor_set_4byte_addr_mode(nor, true);
3343 
3344 	return 0;
3345 }
3346 
3347 /**
3348  * spi_nor_soft_reset() - Perform a software reset
3349  * @nor:	pointer to 'struct spi_nor'
3350  *
3351  * Performs a "Soft Reset and Enter Default Protocol Mode" sequence which resets
3352  * the device to its power-on-reset state. This is useful when the software has
3353  * made some changes to device (volatile) registers and needs to reset it before
3354  * shutting down, for example.
3355  *
3356  * Not every flash supports this sequence. The same set of opcodes might be used
3357  * for some other operation on a flash that does not support this. Support for
3358  * this sequence can be discovered via SFDP in the BFPT table.
3359  *
3360  * Return: 0 on success, -errno otherwise.
3361  */
3362 static void spi_nor_soft_reset(struct spi_nor *nor)
3363 {
3364 	struct spi_mem_op op;
3365 	int ret;
3366 
3367 	op = (struct spi_mem_op)SPINOR_SRSTEN_OP;
3368 
3369 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3370 
3371 	ret = spi_mem_exec_op(nor->spimem, &op);
3372 	if (ret) {
3373 		if (ret != -EOPNOTSUPP)
3374 			dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3375 		return;
3376 	}
3377 
3378 	op = (struct spi_mem_op)SPINOR_SRST_OP;
3379 
3380 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3381 
3382 	ret = spi_mem_exec_op(nor->spimem, &op);
3383 	if (ret) {
3384 		dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3385 		return;
3386 	}
3387 
3388 	/*
3389 	 * Software Reset is not instant, and the delay varies from flash to
3390 	 * flash. Looking at a few flashes, most range somewhere below 100
3391 	 * microseconds. So, sleep for a range of 200-400 us.
3392 	 */
3393 	usleep_range(SPI_NOR_SRST_SLEEP_MIN, SPI_NOR_SRST_SLEEP_MAX);
3394 }
3395 
3396 /* mtd suspend handler */
3397 static int spi_nor_suspend(struct mtd_info *mtd)
3398 {
3399 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3400 	int ret;
3401 
3402 	/* Disable octal DTR mode if we enabled it. */
3403 	ret = spi_nor_set_octal_dtr(nor, false);
3404 	if (ret)
3405 		dev_err(nor->dev, "suspend() failed\n");
3406 
3407 	return ret;
3408 }
3409 
3410 /* mtd resume handler */
3411 static void spi_nor_resume(struct mtd_info *mtd)
3412 {
3413 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3414 	struct device *dev = nor->dev;
3415 	int ret;
3416 
3417 	/* re-initialize the nor chip */
3418 	ret = spi_nor_init(nor);
3419 	if (ret)
3420 		dev_err(dev, "resume() failed\n");
3421 }
3422 
3423 static int spi_nor_get_device(struct mtd_info *mtd)
3424 {
3425 	struct mtd_info *master = mtd_get_master(mtd);
3426 	struct spi_nor *nor = mtd_to_spi_nor(master);
3427 	struct device *dev;
3428 
3429 	if (nor->spimem)
3430 		dev = nor->spimem->spi->controller->dev.parent;
3431 	else
3432 		dev = nor->dev;
3433 
3434 	if (!try_module_get(dev->driver->owner))
3435 		return -ENODEV;
3436 
3437 	return 0;
3438 }
3439 
3440 static void spi_nor_put_device(struct mtd_info *mtd)
3441 {
3442 	struct mtd_info *master = mtd_get_master(mtd);
3443 	struct spi_nor *nor = mtd_to_spi_nor(master);
3444 	struct device *dev;
3445 
3446 	if (nor->spimem)
3447 		dev = nor->spimem->spi->controller->dev.parent;
3448 	else
3449 		dev = nor->dev;
3450 
3451 	module_put(dev->driver->owner);
3452 }
3453 
3454 static void spi_nor_restore(struct spi_nor *nor)
3455 {
3456 	int ret;
3457 
3458 	/* restore the addressing mode */
3459 	if (nor->addr_nbytes == 4 && !(nor->flags & SNOR_F_4B_OPCODES) &&
3460 	    nor->flags & SNOR_F_BROKEN_RESET) {
3461 		ret = spi_nor_set_4byte_addr_mode(nor, false);
3462 		if (ret)
3463 			/*
3464 			 * Do not stop the execution in the hope that the flash
3465 			 * will default to the 3-byte address mode after the
3466 			 * software reset.
3467 			 */
3468 			dev_err(nor->dev, "Failed to exit 4-byte address mode, err = %d\n", ret);
3469 	}
3470 
3471 	if (nor->flags & SNOR_F_SOFT_RESET)
3472 		spi_nor_soft_reset(nor);
3473 }
3474 
3475 static const struct flash_info *spi_nor_match_name(struct spi_nor *nor,
3476 						   const char *name)
3477 {
3478 	unsigned int i, j;
3479 
3480 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
3481 		for (j = 0; j < manufacturers[i]->nparts; j++) {
3482 			if (manufacturers[i]->parts[j].name &&
3483 			    !strcmp(name, manufacturers[i]->parts[j].name)) {
3484 				nor->manufacturer = manufacturers[i];
3485 				return &manufacturers[i]->parts[j];
3486 			}
3487 		}
3488 	}
3489 
3490 	return NULL;
3491 }
3492 
3493 static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
3494 						       const char *name)
3495 {
3496 	const struct flash_info *info = NULL;
3497 
3498 	if (name)
3499 		info = spi_nor_match_name(nor, name);
3500 	/*
3501 	 * Auto-detect if chip name wasn't specified or not found, or the chip
3502 	 * has an ID. If the chip supposedly has an ID, we also do an
3503 	 * auto-detection to compare it later.
3504 	 */
3505 	if (!info || info->id) {
3506 		const struct flash_info *jinfo;
3507 
3508 		jinfo = spi_nor_detect(nor);
3509 		if (IS_ERR(jinfo))
3510 			return jinfo;
3511 
3512 		/*
3513 		 * If caller has specified name of flash model that can normally
3514 		 * be detected using JEDEC, let's verify it.
3515 		 */
3516 		if (info && jinfo != info)
3517 			dev_warn(nor->dev, "found %s, expected %s\n",
3518 				 jinfo->name, info->name);
3519 
3520 		/* If info was set before, JEDEC knows better. */
3521 		info = jinfo;
3522 	}
3523 
3524 	return info;
3525 }
3526 
3527 static u32
3528 spi_nor_get_region_erasesize(const struct spi_nor_erase_region *region,
3529 			     const struct spi_nor_erase_type *erase_type)
3530 {
3531 	int i;
3532 
3533 	if (region->overlaid)
3534 		return region->size;
3535 
3536 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
3537 		if (region->erase_mask & BIT(i))
3538 			return erase_type[i].size;
3539 	}
3540 
3541 	return 0;
3542 }
3543 
3544 static int spi_nor_set_mtd_eraseregions(struct spi_nor *nor)
3545 {
3546 	const struct spi_nor_erase_map *map = &nor->params->erase_map;
3547 	const struct spi_nor_erase_region *region = map->regions;
3548 	struct mtd_erase_region_info *mtd_region;
3549 	struct mtd_info *mtd = &nor->mtd;
3550 	u32 erasesize, i;
3551 
3552 	mtd_region = devm_kcalloc(nor->dev, map->n_regions, sizeof(*mtd_region),
3553 				  GFP_KERNEL);
3554 	if (!mtd_region)
3555 		return -ENOMEM;
3556 
3557 	for (i = 0; i < map->n_regions; i++) {
3558 		erasesize = spi_nor_get_region_erasesize(&region[i],
3559 							 map->erase_type);
3560 		if (!erasesize)
3561 			return -EINVAL;
3562 
3563 		mtd_region[i].erasesize = erasesize;
3564 		mtd_region[i].numblocks = div_u64(region[i].size, erasesize);
3565 		mtd_region[i].offset = region[i].offset;
3566 	}
3567 
3568 	mtd->numeraseregions = map->n_regions;
3569 	mtd->eraseregions = mtd_region;
3570 
3571 	return 0;
3572 }
3573 
3574 static int spi_nor_set_mtd_info(struct spi_nor *nor)
3575 {
3576 	struct mtd_info *mtd = &nor->mtd;
3577 	struct device *dev = nor->dev;
3578 
3579 	spi_nor_set_mtd_locking_ops(nor);
3580 	spi_nor_set_mtd_otp_ops(nor);
3581 
3582 	mtd->dev.parent = dev;
3583 	if (!mtd->name)
3584 		mtd->name = dev_name(dev);
3585 	mtd->type = MTD_NORFLASH;
3586 	mtd->flags = MTD_CAP_NORFLASH;
3587 	/* Unset BIT_WRITEABLE to enable JFFS2 write buffer for ECC'd NOR */
3588 	if (nor->flags & SNOR_F_ECC)
3589 		mtd->flags &= ~MTD_BIT_WRITEABLE;
3590 	if (nor->info->flags & SPI_NOR_NO_ERASE)
3591 		mtd->flags |= MTD_NO_ERASE;
3592 	else
3593 		mtd->_erase = spi_nor_erase;
3594 	mtd->writesize = nor->params->writesize;
3595 	mtd->writebufsize = nor->params->page_size;
3596 	mtd->size = nor->params->size;
3597 	mtd->_read = spi_nor_read;
3598 	/* Might be already set by some SST flashes. */
3599 	if (!mtd->_write)
3600 		mtd->_write = spi_nor_write;
3601 	mtd->_suspend = spi_nor_suspend;
3602 	mtd->_resume = spi_nor_resume;
3603 	mtd->_get_device = spi_nor_get_device;
3604 	mtd->_put_device = spi_nor_put_device;
3605 
3606 	if (!spi_nor_has_uniform_erase(nor))
3607 		return spi_nor_set_mtd_eraseregions(nor);
3608 
3609 	return 0;
3610 }
3611 
3612 static int spi_nor_hw_reset(struct spi_nor *nor)
3613 {
3614 	struct gpio_desc *reset;
3615 
3616 	reset = devm_gpiod_get_optional(nor->dev, "reset", GPIOD_OUT_LOW);
3617 	if (IS_ERR_OR_NULL(reset))
3618 		return PTR_ERR_OR_ZERO(reset);
3619 
3620 	/*
3621 	 * Experimental delay values by looking at different flash device
3622 	 * vendors datasheets.
3623 	 */
3624 	usleep_range(1, 5);
3625 	gpiod_set_value_cansleep(reset, 1);
3626 	usleep_range(100, 150);
3627 	gpiod_set_value_cansleep(reset, 0);
3628 	usleep_range(1000, 1200);
3629 
3630 	return 0;
3631 }
3632 
3633 int spi_nor_scan(struct spi_nor *nor, const char *name,
3634 		 const struct spi_nor_hwcaps *hwcaps)
3635 {
3636 	const struct flash_info *info;
3637 	struct device *dev = nor->dev;
3638 	int ret;
3639 
3640 	ret = spi_nor_check(nor);
3641 	if (ret)
3642 		return ret;
3643 
3644 	/* Reset SPI protocol for all commands. */
3645 	nor->reg_proto = SNOR_PROTO_1_1_1;
3646 	nor->read_proto = SNOR_PROTO_1_1_1;
3647 	nor->write_proto = SNOR_PROTO_1_1_1;
3648 
3649 	/*
3650 	 * We need the bounce buffer early to read/write registers when going
3651 	 * through the spi-mem layer (buffers have to be DMA-able).
3652 	 * For spi-mem drivers, we'll reallocate a new buffer if
3653 	 * nor->params->page_size turns out to be greater than PAGE_SIZE (which
3654 	 * shouldn't happen before long since NOR pages are usually less
3655 	 * than 1KB) after spi_nor_scan() returns.
3656 	 */
3657 	nor->bouncebuf_size = PAGE_SIZE;
3658 	nor->bouncebuf = devm_kmalloc(dev, nor->bouncebuf_size,
3659 				      GFP_KERNEL);
3660 	if (!nor->bouncebuf)
3661 		return -ENOMEM;
3662 
3663 	ret = spi_nor_hw_reset(nor);
3664 	if (ret)
3665 		return ret;
3666 
3667 	info = spi_nor_get_flash_info(nor, name);
3668 	if (IS_ERR(info))
3669 		return PTR_ERR(info);
3670 
3671 	nor->info = info;
3672 
3673 	mutex_init(&nor->lock);
3674 
3675 	/* Init flash parameters based on flash_info struct and SFDP */
3676 	ret = spi_nor_init_params(nor);
3677 	if (ret)
3678 		return ret;
3679 
3680 	if (spi_nor_use_parallel_locking(nor))
3681 		init_waitqueue_head(&nor->rww.wait);
3682 
3683 	/*
3684 	 * Configure the SPI memory:
3685 	 * - select op codes for (Fast) Read, Page Program and Sector Erase.
3686 	 * - set the number of dummy cycles (mode cycles + wait states).
3687 	 * - set the SPI protocols for register and memory accesses.
3688 	 * - set the number of address bytes.
3689 	 */
3690 	ret = spi_nor_setup(nor, hwcaps);
3691 	if (ret)
3692 		return ret;
3693 
3694 	/* Send all the required SPI flash commands to initialize device */
3695 	ret = spi_nor_init(nor);
3696 	if (ret)
3697 		return ret;
3698 
3699 	/* No mtd_info fields should be used up to this point. */
3700 	ret = spi_nor_set_mtd_info(nor);
3701 	if (ret)
3702 		return ret;
3703 
3704 	dev_dbg(dev, "Manufacturer and device ID: %*phN\n",
3705 		SPI_NOR_MAX_ID_LEN, nor->id);
3706 
3707 	return 0;
3708 }
3709 EXPORT_SYMBOL_GPL(spi_nor_scan);
3710 
3711 static int spi_nor_create_read_dirmap(struct spi_nor *nor)
3712 {
3713 	struct spi_mem_dirmap_info info = {
3714 		.op_tmpl = &info.primary_op_tmpl,
3715 		.primary_op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
3716 					      SPI_MEM_OP_ADDR(nor->addr_nbytes, 0, 0),
3717 					      SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
3718 					      SPI_MEM_OP_DATA_IN(0, NULL, 0)),
3719 		.offset = 0,
3720 		.length = nor->params->size,
3721 	};
3722 	struct spi_mem_op *op = info.op_tmpl;
3723 
3724 	spi_nor_spimem_setup_op(nor, op, nor->read_proto);
3725 
3726 	/* convert the dummy cycles to the number of bytes */
3727 	op->dummy.nbytes = (nor->read_dummy * op->dummy.buswidth) / 8;
3728 	if (spi_nor_protocol_is_dtr(nor->read_proto))
3729 		op->dummy.nbytes *= 2;
3730 
3731 	/*
3732 	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3733 	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3734 	 * do it explicitly.
3735 	 */
3736 	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
3737 
3738 	nor->dirmap.rdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3739 						       &info);
3740 	return PTR_ERR_OR_ZERO(nor->dirmap.rdesc);
3741 }
3742 
3743 static int spi_nor_create_write_dirmap(struct spi_nor *nor)
3744 {
3745 	struct spi_mem_dirmap_info info = {
3746 		.op_tmpl = &info.primary_op_tmpl,
3747 		.primary_op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
3748 					      SPI_MEM_OP_ADDR(nor->addr_nbytes, 0, 0),
3749 					      SPI_MEM_OP_NO_DUMMY,
3750 					      SPI_MEM_OP_DATA_OUT(0, NULL, 0)),
3751 		.offset = 0,
3752 		.length = nor->params->size,
3753 	};
3754 	struct spi_mem_op *op = info.op_tmpl;
3755 
3756 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
3757 		op->addr.nbytes = 0;
3758 
3759 	spi_nor_spimem_setup_op(nor, op, nor->write_proto);
3760 
3761 	/*
3762 	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3763 	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3764 	 * do it explicitly.
3765 	 */
3766 	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
3767 
3768 	nor->dirmap.wdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3769 						       &info);
3770 	return PTR_ERR_OR_ZERO(nor->dirmap.wdesc);
3771 }
3772 
3773 static int spi_nor_probe(struct spi_mem *spimem)
3774 {
3775 	struct spi_device *spi = spimem->spi;
3776 	struct device *dev = &spi->dev;
3777 	struct flash_platform_data *data = dev_get_platdata(dev);
3778 	struct spi_nor *nor;
3779 	/*
3780 	 * Enable all caps by default. The core will mask them after
3781 	 * checking what's really supported using spi_mem_supports_op().
3782 	 */
3783 	const struct spi_nor_hwcaps hwcaps = { .mask = SNOR_HWCAPS_ALL };
3784 	char *flash_name;
3785 	int ret;
3786 
3787 	ret = devm_regulator_get_enable(dev, "vcc");
3788 	if (ret)
3789 		return ret;
3790 
3791 	nor = devm_kzalloc(dev, sizeof(*nor), GFP_KERNEL);
3792 	if (!nor)
3793 		return -ENOMEM;
3794 
3795 	nor->spimem = spimem;
3796 	nor->dev = dev;
3797 	spi_nor_set_flash_node(nor, dev->of_node);
3798 
3799 	spi_mem_set_drvdata(spimem, nor);
3800 
3801 	if (data && data->name)
3802 		nor->mtd.name = data->name;
3803 
3804 	if (!nor->mtd.name)
3805 		nor->mtd.name = spi_mem_get_name(spimem);
3806 
3807 	/*
3808 	 * For some (historical?) reason many platforms provide two different
3809 	 * names in flash_platform_data: "name" and "type". Quite often name is
3810 	 * set to "m25p80" and then "type" provides a real chip name.
3811 	 * If that's the case, respect "type" and ignore a "name".
3812 	 */
3813 	if (data && data->type)
3814 		flash_name = data->type;
3815 	else if (!strcmp(spi->modalias, "spi-nor"))
3816 		flash_name = NULL; /* auto-detect */
3817 	else
3818 		flash_name = spi->modalias;
3819 
3820 	ret = spi_nor_scan(nor, flash_name, &hwcaps);
3821 	if (ret)
3822 		return ret;
3823 
3824 	spi_nor_debugfs_register(nor);
3825 
3826 	/*
3827 	 * None of the existing parts have > 512B pages, but let's play safe
3828 	 * and add this logic so that if anyone ever adds support for such
3829 	 * a NOR we don't end up with buffer overflows.
3830 	 */
3831 	if (nor->params->page_size > PAGE_SIZE) {
3832 		nor->bouncebuf_size = nor->params->page_size;
3833 		devm_kfree(dev, nor->bouncebuf);
3834 		nor->bouncebuf = devm_kmalloc(dev, nor->bouncebuf_size,
3835 					      GFP_KERNEL);
3836 		if (!nor->bouncebuf)
3837 			return -ENOMEM;
3838 	}
3839 
3840 	ret = spi_nor_create_read_dirmap(nor);
3841 	if (ret)
3842 		return ret;
3843 
3844 	ret = spi_nor_create_write_dirmap(nor);
3845 	if (ret)
3846 		return ret;
3847 
3848 	return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
3849 				   data ? data->nr_parts : 0);
3850 }
3851 
3852 static int spi_nor_remove(struct spi_mem *spimem)
3853 {
3854 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3855 
3856 	spi_nor_restore(nor);
3857 
3858 	/* Clean up MTD stuff. */
3859 	return mtd_device_unregister(&nor->mtd);
3860 }
3861 
3862 static void spi_nor_shutdown(struct spi_mem *spimem)
3863 {
3864 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3865 
3866 	spi_nor_restore(nor);
3867 }
3868 
3869 /*
3870  * Do NOT add to this array without reading the following:
3871  *
3872  * Historically, many flash devices are bound to this driver by their name. But
3873  * since most of these flash are compatible to some extent, and their
3874  * differences can often be differentiated by the JEDEC read-ID command, we
3875  * encourage new users to add support to the spi-nor library, and simply bind
3876  * against a generic string here (e.g., "jedec,spi-nor").
3877  *
3878  * Many flash names are kept here in this list to keep them available
3879  * as module aliases for existing platforms.
3880  */
3881 static const struct spi_device_id spi_nor_dev_ids[] = {
3882 	/*
3883 	 * Allow non-DT platform devices to bind to the "spi-nor" modalias, and
3884 	 * hack around the fact that the SPI core does not provide uevent
3885 	 * matching for .of_match_table
3886 	 */
3887 	{"spi-nor"},
3888 
3889 	/*
3890 	 * Entries not used in DTs that should be safe to drop after replacing
3891 	 * them with "spi-nor" in platform data.
3892 	 */
3893 	{"s25sl064a"},	{"w25x16"},	{"m25p10"},	{"m25px64"},
3894 
3895 	/*
3896 	 * Entries that were used in DTs without "jedec,spi-nor" fallback and
3897 	 * should be kept for backward compatibility.
3898 	 */
3899 	{"at25df321a"},	{"at25df641"},	{"at26df081a"},
3900 	{"mx25l4005a"},	{"mx25l1606e"},	{"mx25l6405d"},	{"mx25l12805d"},
3901 	{"mx25l25635e"},{"mx66l51235l"},
3902 	{"n25q064"},	{"n25q128a11"},	{"n25q128a13"},	{"n25q512a"},
3903 	{"s25fl256s1"},	{"s25fl512s"},	{"s25sl12801"},	{"s25fl008k"},
3904 	{"s25fl064k"},
3905 	{"sst25vf040b"},{"sst25vf016b"},{"sst25vf032b"},{"sst25wf040"},
3906 	{"m25p40"},	{"m25p80"},	{"m25p16"},	{"m25p32"},
3907 	{"m25p64"},	{"m25p128"},
3908 	{"w25x80"},	{"w25x32"},	{"w25q32"},	{"w25q32dw"},
3909 	{"w25q80bl"},	{"w25q128"},	{"w25q256"},
3910 
3911 	/* Flashes that can't be detected using JEDEC */
3912 	{"m25p05-nonjedec"},	{"m25p10-nonjedec"},	{"m25p20-nonjedec"},
3913 	{"m25p40-nonjedec"},	{"m25p80-nonjedec"},	{"m25p16-nonjedec"},
3914 	{"m25p32-nonjedec"},	{"m25p64-nonjedec"},	{"m25p128-nonjedec"},
3915 
3916 	/* Everspin MRAMs (non-JEDEC) */
3917 	{ "mr25h128" }, /* 128 Kib, 40 MHz */
3918 	{ "mr25h256" }, /* 256 Kib, 40 MHz */
3919 	{ "mr25h10" },  /*   1 Mib, 40 MHz */
3920 	{ "mr25h40" },  /*   4 Mib, 40 MHz */
3921 
3922 	{ },
3923 };
3924 MODULE_DEVICE_TABLE(spi, spi_nor_dev_ids);
3925 
3926 static const struct of_device_id spi_nor_of_table[] = {
3927 	/*
3928 	 * Generic compatibility for SPI NOR that can be identified by the
3929 	 * JEDEC READ ID opcode (0x9F). Use this, if possible.
3930 	 */
3931 	{ .compatible = "jedec,spi-nor" },
3932 	{ /* sentinel */ },
3933 };
3934 MODULE_DEVICE_TABLE(of, spi_nor_of_table);
3935 
3936 /*
3937  * REVISIT: many of these chips have deep power-down modes, which
3938  * should clearly be entered on suspend() to minimize power use.
3939  * And also when they're otherwise idle...
3940  */
3941 static struct spi_mem_driver spi_nor_driver = {
3942 	.spidrv = {
3943 		.driver = {
3944 			.name = "spi-nor",
3945 			.of_match_table = spi_nor_of_table,
3946 			.dev_groups = spi_nor_sysfs_groups,
3947 		},
3948 		.id_table = spi_nor_dev_ids,
3949 	},
3950 	.probe = spi_nor_probe,
3951 	.remove = spi_nor_remove,
3952 	.shutdown = spi_nor_shutdown,
3953 };
3954 
3955 static int __init spi_nor_module_init(void)
3956 {
3957 	return spi_mem_driver_register(&spi_nor_driver);
3958 }
3959 module_init(spi_nor_module_init);
3960 
3961 static void __exit spi_nor_module_exit(void)
3962 {
3963 	spi_mem_driver_unregister(&spi_nor_driver);
3964 	spi_nor_debugfs_shutdown();
3965 }
3966 module_exit(spi_nor_module_exit);
3967 
3968 MODULE_LICENSE("GPL v2");
3969 MODULE_AUTHOR("Huang Shijie <shijie8@gmail.com>");
3970 MODULE_AUTHOR("Mike Lavender");
3971 MODULE_DESCRIPTION("framework for SPI NOR");
3972