xref: /openbmc/linux/drivers/mtd/spi-nor/core.c (revision 36acd5e2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Based on m25p80.c, by Mike Lavender (mike@steroidmicros.com), with
4  * influence from lart.c (Abraham Van Der Merwe) and mtd_dataflash.c
5  *
6  * Copyright (C) 2005, Intec Automation Inc.
7  * Copyright (C) 2014, Freescale Semiconductor, Inc.
8  */
9 
10 #include <linux/err.h>
11 #include <linux/errno.h>
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/mutex.h>
15 #include <linux/math64.h>
16 #include <linux/sizes.h>
17 #include <linux/slab.h>
18 
19 #include <linux/mtd/mtd.h>
20 #include <linux/of_platform.h>
21 #include <linux/sched/task_stack.h>
22 #include <linux/spi/flash.h>
23 #include <linux/mtd/spi-nor.h>
24 
25 #include "core.h"
26 
27 /* Define max times to check status register before we give up. */
28 
29 /*
30  * For everything but full-chip erase; probably could be much smaller, but kept
31  * around for safety for now
32  */
33 #define DEFAULT_READY_WAIT_JIFFIES		(40UL * HZ)
34 
35 /*
36  * For full-chip erase, calibrated to a 2MB flash (M25P16); should be scaled up
37  * for larger flash
38  */
39 #define CHIP_ERASE_2MB_READY_WAIT_JIFFIES	(40UL * HZ)
40 
41 #define SPI_NOR_MAX_ADDR_WIDTH	4
42 
43 #define SPI_NOR_SRST_SLEEP_MIN 200
44 #define SPI_NOR_SRST_SLEEP_MAX 400
45 
46 /**
47  * spi_nor_get_cmd_ext() - Get the command opcode extension based on the
48  *			   extension type.
49  * @nor:		pointer to a 'struct spi_nor'
50  * @op:			pointer to the 'struct spi_mem_op' whose properties
51  *			need to be initialized.
52  *
53  * Right now, only "repeat" and "invert" are supported.
54  *
55  * Return: The opcode extension.
56  */
57 static u8 spi_nor_get_cmd_ext(const struct spi_nor *nor,
58 			      const struct spi_mem_op *op)
59 {
60 	switch (nor->cmd_ext_type) {
61 	case SPI_NOR_EXT_INVERT:
62 		return ~op->cmd.opcode;
63 
64 	case SPI_NOR_EXT_REPEAT:
65 		return op->cmd.opcode;
66 
67 	default:
68 		dev_err(nor->dev, "Unknown command extension type\n");
69 		return 0;
70 	}
71 }
72 
73 /**
74  * spi_nor_spimem_setup_op() - Set up common properties of a spi-mem op.
75  * @nor:		pointer to a 'struct spi_nor'
76  * @op:			pointer to the 'struct spi_mem_op' whose properties
77  *			need to be initialized.
78  * @proto:		the protocol from which the properties need to be set.
79  */
80 void spi_nor_spimem_setup_op(const struct spi_nor *nor,
81 			     struct spi_mem_op *op,
82 			     const enum spi_nor_protocol proto)
83 {
84 	u8 ext;
85 
86 	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(proto);
87 
88 	if (op->addr.nbytes)
89 		op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
90 
91 	if (op->dummy.nbytes)
92 		op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
93 
94 	if (op->data.nbytes)
95 		op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
96 
97 	if (spi_nor_protocol_is_dtr(proto)) {
98 		/*
99 		 * SPIMEM supports mixed DTR modes, but right now we can only
100 		 * have all phases either DTR or STR. IOW, SPIMEM can have
101 		 * something like 4S-4D-4D, but SPI NOR can't. So, set all 4
102 		 * phases to either DTR or STR.
103 		 */
104 		op->cmd.dtr = true;
105 		op->addr.dtr = true;
106 		op->dummy.dtr = true;
107 		op->data.dtr = true;
108 
109 		/* 2 bytes per clock cycle in DTR mode. */
110 		op->dummy.nbytes *= 2;
111 
112 		ext = spi_nor_get_cmd_ext(nor, op);
113 		op->cmd.opcode = (op->cmd.opcode << 8) | ext;
114 		op->cmd.nbytes = 2;
115 	}
116 }
117 
118 /**
119  * spi_nor_spimem_bounce() - check if a bounce buffer is needed for the data
120  *                           transfer
121  * @nor:        pointer to 'struct spi_nor'
122  * @op:         pointer to 'struct spi_mem_op' template for transfer
123  *
124  * If we have to use the bounce buffer, the data field in @op will be updated.
125  *
126  * Return: true if the bounce buffer is needed, false if not
127  */
128 static bool spi_nor_spimem_bounce(struct spi_nor *nor, struct spi_mem_op *op)
129 {
130 	/* op->data.buf.in occupies the same memory as op->data.buf.out */
131 	if (object_is_on_stack(op->data.buf.in) ||
132 	    !virt_addr_valid(op->data.buf.in)) {
133 		if (op->data.nbytes > nor->bouncebuf_size)
134 			op->data.nbytes = nor->bouncebuf_size;
135 		op->data.buf.in = nor->bouncebuf;
136 		return true;
137 	}
138 
139 	return false;
140 }
141 
142 /**
143  * spi_nor_spimem_exec_op() - execute a memory operation
144  * @nor:        pointer to 'struct spi_nor'
145  * @op:         pointer to 'struct spi_mem_op' template for transfer
146  *
147  * Return: 0 on success, -error otherwise.
148  */
149 static int spi_nor_spimem_exec_op(struct spi_nor *nor, struct spi_mem_op *op)
150 {
151 	int error;
152 
153 	error = spi_mem_adjust_op_size(nor->spimem, op);
154 	if (error)
155 		return error;
156 
157 	return spi_mem_exec_op(nor->spimem, op);
158 }
159 
160 static int spi_nor_controller_ops_read_reg(struct spi_nor *nor, u8 opcode,
161 					   u8 *buf, size_t len)
162 {
163 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
164 		return -EOPNOTSUPP;
165 
166 	return nor->controller_ops->read_reg(nor, opcode, buf, len);
167 }
168 
169 static int spi_nor_controller_ops_write_reg(struct spi_nor *nor, u8 opcode,
170 					    const u8 *buf, size_t len)
171 {
172 	if (spi_nor_protocol_is_dtr(nor->reg_proto))
173 		return -EOPNOTSUPP;
174 
175 	return nor->controller_ops->write_reg(nor, opcode, buf, len);
176 }
177 
178 static int spi_nor_controller_ops_erase(struct spi_nor *nor, loff_t offs)
179 {
180 	if (spi_nor_protocol_is_dtr(nor->write_proto))
181 		return -EOPNOTSUPP;
182 
183 	return nor->controller_ops->erase(nor, offs);
184 }
185 
186 /**
187  * spi_nor_spimem_read_data() - read data from flash's memory region via
188  *                              spi-mem
189  * @nor:        pointer to 'struct spi_nor'
190  * @from:       offset to read from
191  * @len:        number of bytes to read
192  * @buf:        pointer to dst buffer
193  *
194  * Return: number of bytes read successfully, -errno otherwise
195  */
196 static ssize_t spi_nor_spimem_read_data(struct spi_nor *nor, loff_t from,
197 					size_t len, u8 *buf)
198 {
199 	struct spi_mem_op op =
200 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
201 			   SPI_MEM_OP_ADDR(nor->addr_width, from, 0),
202 			   SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
203 			   SPI_MEM_OP_DATA_IN(len, buf, 0));
204 	bool usebouncebuf;
205 	ssize_t nbytes;
206 	int error;
207 
208 	spi_nor_spimem_setup_op(nor, &op, nor->read_proto);
209 
210 	/* convert the dummy cycles to the number of bytes */
211 	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
212 	if (spi_nor_protocol_is_dtr(nor->read_proto))
213 		op.dummy.nbytes *= 2;
214 
215 	usebouncebuf = spi_nor_spimem_bounce(nor, &op);
216 
217 	if (nor->dirmap.rdesc) {
218 		nbytes = spi_mem_dirmap_read(nor->dirmap.rdesc, op.addr.val,
219 					     op.data.nbytes, op.data.buf.in);
220 	} else {
221 		error = spi_nor_spimem_exec_op(nor, &op);
222 		if (error)
223 			return error;
224 		nbytes = op.data.nbytes;
225 	}
226 
227 	if (usebouncebuf && nbytes > 0)
228 		memcpy(buf, op.data.buf.in, nbytes);
229 
230 	return nbytes;
231 }
232 
233 /**
234  * spi_nor_read_data() - read data from flash memory
235  * @nor:        pointer to 'struct spi_nor'
236  * @from:       offset to read from
237  * @len:        number of bytes to read
238  * @buf:        pointer to dst buffer
239  *
240  * Return: number of bytes read successfully, -errno otherwise
241  */
242 ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len, u8 *buf)
243 {
244 	if (nor->spimem)
245 		return spi_nor_spimem_read_data(nor, from, len, buf);
246 
247 	return nor->controller_ops->read(nor, from, len, buf);
248 }
249 
250 /**
251  * spi_nor_spimem_write_data() - write data to flash memory via
252  *                               spi-mem
253  * @nor:        pointer to 'struct spi_nor'
254  * @to:         offset to write to
255  * @len:        number of bytes to write
256  * @buf:        pointer to src buffer
257  *
258  * Return: number of bytes written successfully, -errno otherwise
259  */
260 static ssize_t spi_nor_spimem_write_data(struct spi_nor *nor, loff_t to,
261 					 size_t len, const u8 *buf)
262 {
263 	struct spi_mem_op op =
264 		SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
265 			   SPI_MEM_OP_ADDR(nor->addr_width, to, 0),
266 			   SPI_MEM_OP_NO_DUMMY,
267 			   SPI_MEM_OP_DATA_OUT(len, buf, 0));
268 	ssize_t nbytes;
269 	int error;
270 
271 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
272 		op.addr.nbytes = 0;
273 
274 	spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
275 
276 	if (spi_nor_spimem_bounce(nor, &op))
277 		memcpy(nor->bouncebuf, buf, op.data.nbytes);
278 
279 	if (nor->dirmap.wdesc) {
280 		nbytes = spi_mem_dirmap_write(nor->dirmap.wdesc, op.addr.val,
281 					      op.data.nbytes, op.data.buf.out);
282 	} else {
283 		error = spi_nor_spimem_exec_op(nor, &op);
284 		if (error)
285 			return error;
286 		nbytes = op.data.nbytes;
287 	}
288 
289 	return nbytes;
290 }
291 
292 /**
293  * spi_nor_write_data() - write data to flash memory
294  * @nor:        pointer to 'struct spi_nor'
295  * @to:         offset to write to
296  * @len:        number of bytes to write
297  * @buf:        pointer to src buffer
298  *
299  * Return: number of bytes written successfully, -errno otherwise
300  */
301 ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
302 			   const u8 *buf)
303 {
304 	if (nor->spimem)
305 		return spi_nor_spimem_write_data(nor, to, len, buf);
306 
307 	return nor->controller_ops->write(nor, to, len, buf);
308 }
309 
310 /**
311  * spi_nor_write_enable() - Set write enable latch with Write Enable command.
312  * @nor:	pointer to 'struct spi_nor'.
313  *
314  * Return: 0 on success, -errno otherwise.
315  */
316 int spi_nor_write_enable(struct spi_nor *nor)
317 {
318 	int ret;
319 
320 	if (nor->spimem) {
321 		struct spi_mem_op op =
322 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WREN, 0),
323 				   SPI_MEM_OP_NO_ADDR,
324 				   SPI_MEM_OP_NO_DUMMY,
325 				   SPI_MEM_OP_NO_DATA);
326 
327 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
328 
329 		ret = spi_mem_exec_op(nor->spimem, &op);
330 	} else {
331 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WREN,
332 						       NULL, 0);
333 	}
334 
335 	if (ret)
336 		dev_dbg(nor->dev, "error %d on Write Enable\n", ret);
337 
338 	return ret;
339 }
340 
341 /**
342  * spi_nor_write_disable() - Send Write Disable instruction to the chip.
343  * @nor:	pointer to 'struct spi_nor'.
344  *
345  * Return: 0 on success, -errno otherwise.
346  */
347 int spi_nor_write_disable(struct spi_nor *nor)
348 {
349 	int ret;
350 
351 	if (nor->spimem) {
352 		struct spi_mem_op op =
353 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRDI, 0),
354 				   SPI_MEM_OP_NO_ADDR,
355 				   SPI_MEM_OP_NO_DUMMY,
356 				   SPI_MEM_OP_NO_DATA);
357 
358 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
359 
360 		ret = spi_mem_exec_op(nor->spimem, &op);
361 	} else {
362 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRDI,
363 						       NULL, 0);
364 	}
365 
366 	if (ret)
367 		dev_dbg(nor->dev, "error %d on Write Disable\n", ret);
368 
369 	return ret;
370 }
371 
372 /**
373  * spi_nor_read_sr() - Read the Status Register.
374  * @nor:	pointer to 'struct spi_nor'.
375  * @sr:		pointer to a DMA-able buffer where the value of the
376  *              Status Register will be written. Should be at least 2 bytes.
377  *
378  * Return: 0 on success, -errno otherwise.
379  */
380 int spi_nor_read_sr(struct spi_nor *nor, u8 *sr)
381 {
382 	int ret;
383 
384 	if (nor->spimem) {
385 		struct spi_mem_op op =
386 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDSR, 0),
387 				   SPI_MEM_OP_NO_ADDR,
388 				   SPI_MEM_OP_NO_DUMMY,
389 				   SPI_MEM_OP_DATA_IN(1, sr, 0));
390 
391 		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
392 			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
393 			op.dummy.nbytes = nor->params->rdsr_dummy;
394 			/*
395 			 * We don't want to read only one byte in DTR mode. So,
396 			 * read 2 and then discard the second byte.
397 			 */
398 			op.data.nbytes = 2;
399 		}
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_read_reg(nor, SPINOR_OP_RDSR, sr,
406 						      1);
407 	}
408 
409 	if (ret)
410 		dev_dbg(nor->dev, "error %d reading SR\n", ret);
411 
412 	return ret;
413 }
414 
415 /**
416  * spi_nor_read_fsr() - Read the Flag Status Register.
417  * @nor:	pointer to 'struct spi_nor'
418  * @fsr:	pointer to a DMA-able buffer where the value of the
419  *              Flag Status Register will be written. Should be at least 2
420  *              bytes.
421  *
422  * Return: 0 on success, -errno otherwise.
423  */
424 static int spi_nor_read_fsr(struct spi_nor *nor, u8 *fsr)
425 {
426 	int ret;
427 
428 	if (nor->spimem) {
429 		struct spi_mem_op op =
430 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDFSR, 0),
431 				   SPI_MEM_OP_NO_ADDR,
432 				   SPI_MEM_OP_NO_DUMMY,
433 				   SPI_MEM_OP_DATA_IN(1, fsr, 0));
434 
435 		if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
436 			op.addr.nbytes = nor->params->rdsr_addr_nbytes;
437 			op.dummy.nbytes = nor->params->rdsr_dummy;
438 			/*
439 			 * We don't want to read only one byte in DTR mode. So,
440 			 * read 2 and then discard the second byte.
441 			 */
442 			op.data.nbytes = 2;
443 		}
444 
445 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
446 
447 		ret = spi_mem_exec_op(nor->spimem, &op);
448 	} else {
449 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDFSR, fsr,
450 						      1);
451 	}
452 
453 	if (ret)
454 		dev_dbg(nor->dev, "error %d reading FSR\n", ret);
455 
456 	return ret;
457 }
458 
459 /**
460  * spi_nor_read_cr() - Read the Configuration Register using the
461  * SPINOR_OP_RDCR (35h) command.
462  * @nor:	pointer to 'struct spi_nor'
463  * @cr:		pointer to a DMA-able buffer where the value of the
464  *              Configuration Register will be written.
465  *
466  * Return: 0 on success, -errno otherwise.
467  */
468 static int spi_nor_read_cr(struct spi_nor *nor, u8 *cr)
469 {
470 	int ret;
471 
472 	if (nor->spimem) {
473 		struct spi_mem_op op =
474 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDCR, 0),
475 				   SPI_MEM_OP_NO_ADDR,
476 				   SPI_MEM_OP_NO_DUMMY,
477 				   SPI_MEM_OP_DATA_IN(1, cr, 0));
478 
479 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
480 
481 		ret = spi_mem_exec_op(nor->spimem, &op);
482 	} else {
483 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDCR, cr,
484 						      1);
485 	}
486 
487 	if (ret)
488 		dev_dbg(nor->dev, "error %d reading CR\n", ret);
489 
490 	return ret;
491 }
492 
493 /**
494  * spi_nor_set_4byte_addr_mode() - Enter/Exit 4-byte address mode.
495  * @nor:	pointer to 'struct spi_nor'.
496  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
497  *		address mode.
498  *
499  * Return: 0 on success, -errno otherwise.
500  */
501 int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
502 {
503 	int ret;
504 
505 	if (nor->spimem) {
506 		struct spi_mem_op op =
507 			SPI_MEM_OP(SPI_MEM_OP_CMD(enable ?
508 						  SPINOR_OP_EN4B :
509 						  SPINOR_OP_EX4B,
510 						  0),
511 				  SPI_MEM_OP_NO_ADDR,
512 				  SPI_MEM_OP_NO_DUMMY,
513 				  SPI_MEM_OP_NO_DATA);
514 
515 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
516 
517 		ret = spi_mem_exec_op(nor->spimem, &op);
518 	} else {
519 		ret = spi_nor_controller_ops_write_reg(nor,
520 						       enable ? SPINOR_OP_EN4B :
521 								SPINOR_OP_EX4B,
522 						       NULL, 0);
523 	}
524 
525 	if (ret)
526 		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
527 
528 	return ret;
529 }
530 
531 /**
532  * spansion_set_4byte_addr_mode() - Set 4-byte address mode for Spansion
533  * flashes.
534  * @nor:	pointer to 'struct spi_nor'.
535  * @enable:	true to enter the 4-byte address mode, false to exit the 4-byte
536  *		address mode.
537  *
538  * Return: 0 on success, -errno otherwise.
539  */
540 static int spansion_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
541 {
542 	int ret;
543 
544 	nor->bouncebuf[0] = enable << 7;
545 
546 	if (nor->spimem) {
547 		struct spi_mem_op op =
548 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_BRWR, 0),
549 				   SPI_MEM_OP_NO_ADDR,
550 				   SPI_MEM_OP_NO_DUMMY,
551 				   SPI_MEM_OP_DATA_OUT(1, nor->bouncebuf, 0));
552 
553 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
554 
555 		ret = spi_mem_exec_op(nor->spimem, &op);
556 	} else {
557 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_BRWR,
558 						       nor->bouncebuf, 1);
559 	}
560 
561 	if (ret)
562 		dev_dbg(nor->dev, "error %d setting 4-byte mode\n", ret);
563 
564 	return ret;
565 }
566 
567 /**
568  * spi_nor_write_ear() - Write Extended Address Register.
569  * @nor:	pointer to 'struct spi_nor'.
570  * @ear:	value to write to the Extended Address Register.
571  *
572  * Return: 0 on success, -errno otherwise.
573  */
574 int spi_nor_write_ear(struct spi_nor *nor, u8 ear)
575 {
576 	int ret;
577 
578 	nor->bouncebuf[0] = ear;
579 
580 	if (nor->spimem) {
581 		struct spi_mem_op op =
582 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WREAR, 0),
583 				   SPI_MEM_OP_NO_ADDR,
584 				   SPI_MEM_OP_NO_DUMMY,
585 				   SPI_MEM_OP_DATA_OUT(1, nor->bouncebuf, 0));
586 
587 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
588 
589 		ret = spi_mem_exec_op(nor->spimem, &op);
590 	} else {
591 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WREAR,
592 						       nor->bouncebuf, 1);
593 	}
594 
595 	if (ret)
596 		dev_dbg(nor->dev, "error %d writing EAR\n", ret);
597 
598 	return ret;
599 }
600 
601 /**
602  * spi_nor_xread_sr() - Read the Status Register on S3AN flashes.
603  * @nor:	pointer to 'struct spi_nor'.
604  * @sr:		pointer to a DMA-able buffer where the value of the
605  *              Status Register will be written.
606  *
607  * Return: 0 on success, -errno otherwise.
608  */
609 int spi_nor_xread_sr(struct spi_nor *nor, u8 *sr)
610 {
611 	int ret;
612 
613 	if (nor->spimem) {
614 		struct spi_mem_op op =
615 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_XRDSR, 0),
616 				   SPI_MEM_OP_NO_ADDR,
617 				   SPI_MEM_OP_NO_DUMMY,
618 				   SPI_MEM_OP_DATA_IN(1, sr, 0));
619 
620 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
621 
622 		ret = spi_mem_exec_op(nor->spimem, &op);
623 	} else {
624 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_XRDSR, sr,
625 						      1);
626 	}
627 
628 	if (ret)
629 		dev_dbg(nor->dev, "error %d reading XRDSR\n", ret);
630 
631 	return ret;
632 }
633 
634 /**
635  * spi_nor_xsr_ready() - Query the Status Register of the S3AN flash to see if
636  * the flash is ready for new commands.
637  * @nor:	pointer to 'struct spi_nor'.
638  *
639  * Return: 1 if ready, 0 if not ready, -errno on errors.
640  */
641 static int spi_nor_xsr_ready(struct spi_nor *nor)
642 {
643 	int ret;
644 
645 	ret = spi_nor_xread_sr(nor, nor->bouncebuf);
646 	if (ret)
647 		return ret;
648 
649 	return !!(nor->bouncebuf[0] & XSR_RDY);
650 }
651 
652 /**
653  * spi_nor_clear_sr() - Clear the Status Register.
654  * @nor:	pointer to 'struct spi_nor'.
655  */
656 static void spi_nor_clear_sr(struct spi_nor *nor)
657 {
658 	int ret;
659 
660 	if (nor->spimem) {
661 		struct spi_mem_op op =
662 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CLSR, 0),
663 				   SPI_MEM_OP_NO_ADDR,
664 				   SPI_MEM_OP_NO_DUMMY,
665 				   SPI_MEM_OP_NO_DATA);
666 
667 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
668 
669 		ret = spi_mem_exec_op(nor->spimem, &op);
670 	} else {
671 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_CLSR,
672 						       NULL, 0);
673 	}
674 
675 	if (ret)
676 		dev_dbg(nor->dev, "error %d clearing SR\n", ret);
677 }
678 
679 /**
680  * spi_nor_sr_ready() - Query the Status Register to see if the flash is ready
681  * for new commands.
682  * @nor:	pointer to 'struct spi_nor'.
683  *
684  * Return: 1 if ready, 0 if not ready, -errno on errors.
685  */
686 static int spi_nor_sr_ready(struct spi_nor *nor)
687 {
688 	int ret = spi_nor_read_sr(nor, nor->bouncebuf);
689 
690 	if (ret)
691 		return ret;
692 
693 	if (nor->flags & SNOR_F_USE_CLSR &&
694 	    nor->bouncebuf[0] & (SR_E_ERR | SR_P_ERR)) {
695 		if (nor->bouncebuf[0] & SR_E_ERR)
696 			dev_err(nor->dev, "Erase Error occurred\n");
697 		else
698 			dev_err(nor->dev, "Programming Error occurred\n");
699 
700 		spi_nor_clear_sr(nor);
701 
702 		/*
703 		 * WEL bit remains set to one when an erase or page program
704 		 * error occurs. Issue a Write Disable command to protect
705 		 * against inadvertent writes that can possibly corrupt the
706 		 * contents of the memory.
707 		 */
708 		ret = spi_nor_write_disable(nor);
709 		if (ret)
710 			return ret;
711 
712 		return -EIO;
713 	}
714 
715 	return !(nor->bouncebuf[0] & SR_WIP);
716 }
717 
718 /**
719  * spi_nor_clear_fsr() - Clear the Flag Status Register.
720  * @nor:	pointer to 'struct spi_nor'.
721  */
722 static void spi_nor_clear_fsr(struct spi_nor *nor)
723 {
724 	int ret;
725 
726 	if (nor->spimem) {
727 		struct spi_mem_op op =
728 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CLFSR, 0),
729 				   SPI_MEM_OP_NO_ADDR,
730 				   SPI_MEM_OP_NO_DUMMY,
731 				   SPI_MEM_OP_NO_DATA);
732 
733 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
734 
735 		ret = spi_mem_exec_op(nor->spimem, &op);
736 	} else {
737 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_CLFSR,
738 						       NULL, 0);
739 	}
740 
741 	if (ret)
742 		dev_dbg(nor->dev, "error %d clearing FSR\n", ret);
743 }
744 
745 /**
746  * spi_nor_fsr_ready() - Query the Flag Status Register to see if the flash is
747  * ready for new commands.
748  * @nor:	pointer to 'struct spi_nor'.
749  *
750  * Return: 1 if ready, 0 if not ready, -errno on errors.
751  */
752 static int spi_nor_fsr_ready(struct spi_nor *nor)
753 {
754 	int ret = spi_nor_read_fsr(nor, nor->bouncebuf);
755 
756 	if (ret)
757 		return ret;
758 
759 	if (nor->bouncebuf[0] & (FSR_E_ERR | FSR_P_ERR)) {
760 		if (nor->bouncebuf[0] & FSR_E_ERR)
761 			dev_err(nor->dev, "Erase operation failed.\n");
762 		else
763 			dev_err(nor->dev, "Program operation failed.\n");
764 
765 		if (nor->bouncebuf[0] & FSR_PT_ERR)
766 			dev_err(nor->dev,
767 			"Attempted to modify a protected sector.\n");
768 
769 		spi_nor_clear_fsr(nor);
770 
771 		/*
772 		 * WEL bit remains set to one when an erase or page program
773 		 * error occurs. Issue a Write Disable command to protect
774 		 * against inadvertent writes that can possibly corrupt the
775 		 * contents of the memory.
776 		 */
777 		ret = spi_nor_write_disable(nor);
778 		if (ret)
779 			return ret;
780 
781 		return -EIO;
782 	}
783 
784 	return !!(nor->bouncebuf[0] & FSR_READY);
785 }
786 
787 /**
788  * spi_nor_ready() - Query the flash to see if it is ready for new commands.
789  * @nor:	pointer to 'struct spi_nor'.
790  *
791  * Return: 1 if ready, 0 if not ready, -errno on errors.
792  */
793 static int spi_nor_ready(struct spi_nor *nor)
794 {
795 	int sr, fsr;
796 
797 	if (nor->flags & SNOR_F_READY_XSR_RDY)
798 		sr = spi_nor_xsr_ready(nor);
799 	else
800 		sr = spi_nor_sr_ready(nor);
801 	if (sr < 0)
802 		return sr;
803 	fsr = nor->flags & SNOR_F_USE_FSR ? spi_nor_fsr_ready(nor) : 1;
804 	if (fsr < 0)
805 		return fsr;
806 	return sr && fsr;
807 }
808 
809 /**
810  * spi_nor_wait_till_ready_with_timeout() - Service routine to read the
811  * Status Register until ready, or timeout occurs.
812  * @nor:		pointer to "struct spi_nor".
813  * @timeout_jiffies:	jiffies to wait until timeout.
814  *
815  * Return: 0 on success, -errno otherwise.
816  */
817 static int spi_nor_wait_till_ready_with_timeout(struct spi_nor *nor,
818 						unsigned long timeout_jiffies)
819 {
820 	unsigned long deadline;
821 	int timeout = 0, ret;
822 
823 	deadline = jiffies + timeout_jiffies;
824 
825 	while (!timeout) {
826 		if (time_after_eq(jiffies, deadline))
827 			timeout = 1;
828 
829 		ret = spi_nor_ready(nor);
830 		if (ret < 0)
831 			return ret;
832 		if (ret)
833 			return 0;
834 
835 		cond_resched();
836 	}
837 
838 	dev_dbg(nor->dev, "flash operation timed out\n");
839 
840 	return -ETIMEDOUT;
841 }
842 
843 /**
844  * spi_nor_wait_till_ready() - Wait for a predefined amount of time for the
845  * flash to be ready, or timeout occurs.
846  * @nor:	pointer to "struct spi_nor".
847  *
848  * Return: 0 on success, -errno otherwise.
849  */
850 int spi_nor_wait_till_ready(struct spi_nor *nor)
851 {
852 	return spi_nor_wait_till_ready_with_timeout(nor,
853 						    DEFAULT_READY_WAIT_JIFFIES);
854 }
855 
856 /**
857  * spi_nor_write_sr() - Write the Status Register.
858  * @nor:	pointer to 'struct spi_nor'.
859  * @sr:		pointer to DMA-able buffer to write to the Status Register.
860  * @len:	number of bytes to write to the Status Register.
861  *
862  * Return: 0 on success, -errno otherwise.
863  */
864 int spi_nor_write_sr(struct spi_nor *nor, const u8 *sr, size_t len)
865 {
866 	int ret;
867 
868 	ret = spi_nor_write_enable(nor);
869 	if (ret)
870 		return ret;
871 
872 	if (nor->spimem) {
873 		struct spi_mem_op op =
874 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRSR, 0),
875 				   SPI_MEM_OP_NO_ADDR,
876 				   SPI_MEM_OP_NO_DUMMY,
877 				   SPI_MEM_OP_DATA_OUT(len, sr, 0));
878 
879 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
880 
881 		ret = spi_mem_exec_op(nor->spimem, &op);
882 	} else {
883 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR, sr,
884 						       len);
885 	}
886 
887 	if (ret) {
888 		dev_dbg(nor->dev, "error %d writing SR\n", ret);
889 		return ret;
890 	}
891 
892 	return spi_nor_wait_till_ready(nor);
893 }
894 
895 /**
896  * spi_nor_write_sr1_and_check() - Write one byte to the Status Register 1 and
897  * ensure that the byte written match the received value.
898  * @nor:	pointer to a 'struct spi_nor'.
899  * @sr1:	byte value to be written to the Status Register.
900  *
901  * Return: 0 on success, -errno otherwise.
902  */
903 static int spi_nor_write_sr1_and_check(struct spi_nor *nor, u8 sr1)
904 {
905 	int ret;
906 
907 	nor->bouncebuf[0] = sr1;
908 
909 	ret = spi_nor_write_sr(nor, nor->bouncebuf, 1);
910 	if (ret)
911 		return ret;
912 
913 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
914 	if (ret)
915 		return ret;
916 
917 	if (nor->bouncebuf[0] != sr1) {
918 		dev_dbg(nor->dev, "SR1: read back test failed\n");
919 		return -EIO;
920 	}
921 
922 	return 0;
923 }
924 
925 /**
926  * spi_nor_write_16bit_sr_and_check() - Write the Status Register 1 and the
927  * Status Register 2 in one shot. Ensure that the byte written in the Status
928  * Register 1 match the received value, and that the 16-bit Write did not
929  * affect what was already in the Status Register 2.
930  * @nor:	pointer to a 'struct spi_nor'.
931  * @sr1:	byte value to be written to the Status Register 1.
932  *
933  * Return: 0 on success, -errno otherwise.
934  */
935 static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1)
936 {
937 	int ret;
938 	u8 *sr_cr = nor->bouncebuf;
939 	u8 cr_written;
940 
941 	/* Make sure we don't overwrite the contents of Status Register 2. */
942 	if (!(nor->flags & SNOR_F_NO_READ_CR)) {
943 		ret = spi_nor_read_cr(nor, &sr_cr[1]);
944 		if (ret)
945 			return ret;
946 	} else if (nor->params->quad_enable) {
947 		/*
948 		 * If the Status Register 2 Read command (35h) is not
949 		 * supported, we should at least be sure we don't
950 		 * change the value of the SR2 Quad Enable bit.
951 		 *
952 		 * We can safely assume that when the Quad Enable method is
953 		 * set, the value of the QE bit is one, as a consequence of the
954 		 * nor->params->quad_enable() call.
955 		 *
956 		 * We can safely assume that the Quad Enable bit is present in
957 		 * the Status Register 2 at BIT(1). According to the JESD216
958 		 * revB standard, BFPT DWORDS[15], bits 22:20, the 16-bit
959 		 * Write Status (01h) command is available just for the cases
960 		 * in which the QE bit is described in SR2 at BIT(1).
961 		 */
962 		sr_cr[1] = SR2_QUAD_EN_BIT1;
963 	} else {
964 		sr_cr[1] = 0;
965 	}
966 
967 	sr_cr[0] = sr1;
968 
969 	ret = spi_nor_write_sr(nor, sr_cr, 2);
970 	if (ret)
971 		return ret;
972 
973 	if (nor->flags & SNOR_F_NO_READ_CR)
974 		return 0;
975 
976 	cr_written = sr_cr[1];
977 
978 	ret = spi_nor_read_cr(nor, &sr_cr[1]);
979 	if (ret)
980 		return ret;
981 
982 	if (cr_written != sr_cr[1]) {
983 		dev_dbg(nor->dev, "CR: read back test failed\n");
984 		return -EIO;
985 	}
986 
987 	return 0;
988 }
989 
990 /**
991  * spi_nor_write_16bit_cr_and_check() - Write the Status Register 1 and the
992  * Configuration Register in one shot. Ensure that the byte written in the
993  * Configuration Register match the received value, and that the 16-bit Write
994  * did not affect what was already in the Status Register 1.
995  * @nor:	pointer to a 'struct spi_nor'.
996  * @cr:		byte value to be written to the Configuration Register.
997  *
998  * Return: 0 on success, -errno otherwise.
999  */
1000 static int spi_nor_write_16bit_cr_and_check(struct spi_nor *nor, u8 cr)
1001 {
1002 	int ret;
1003 	u8 *sr_cr = nor->bouncebuf;
1004 	u8 sr_written;
1005 
1006 	/* Keep the current value of the Status Register 1. */
1007 	ret = spi_nor_read_sr(nor, sr_cr);
1008 	if (ret)
1009 		return ret;
1010 
1011 	sr_cr[1] = cr;
1012 
1013 	ret = spi_nor_write_sr(nor, sr_cr, 2);
1014 	if (ret)
1015 		return ret;
1016 
1017 	sr_written = sr_cr[0];
1018 
1019 	ret = spi_nor_read_sr(nor, sr_cr);
1020 	if (ret)
1021 		return ret;
1022 
1023 	if (sr_written != sr_cr[0]) {
1024 		dev_dbg(nor->dev, "SR: Read back test failed\n");
1025 		return -EIO;
1026 	}
1027 
1028 	if (nor->flags & SNOR_F_NO_READ_CR)
1029 		return 0;
1030 
1031 	ret = spi_nor_read_cr(nor, &sr_cr[1]);
1032 	if (ret)
1033 		return ret;
1034 
1035 	if (cr != sr_cr[1]) {
1036 		dev_dbg(nor->dev, "CR: read back test failed\n");
1037 		return -EIO;
1038 	}
1039 
1040 	return 0;
1041 }
1042 
1043 /**
1044  * spi_nor_write_sr_and_check() - Write the Status Register 1 and ensure that
1045  * the byte written match the received value without affecting other bits in the
1046  * Status Register 1 and 2.
1047  * @nor:	pointer to a 'struct spi_nor'.
1048  * @sr1:	byte value to be written to the Status Register.
1049  *
1050  * Return: 0 on success, -errno otherwise.
1051  */
1052 int spi_nor_write_sr_and_check(struct spi_nor *nor, u8 sr1)
1053 {
1054 	if (nor->flags & SNOR_F_HAS_16BIT_SR)
1055 		return spi_nor_write_16bit_sr_and_check(nor, sr1);
1056 
1057 	return spi_nor_write_sr1_and_check(nor, sr1);
1058 }
1059 
1060 /**
1061  * spi_nor_write_sr2() - Write the Status Register 2 using the
1062  * SPINOR_OP_WRSR2 (3eh) command.
1063  * @nor:	pointer to 'struct spi_nor'.
1064  * @sr2:	pointer to DMA-able buffer to write to the Status Register 2.
1065  *
1066  * Return: 0 on success, -errno otherwise.
1067  */
1068 static int spi_nor_write_sr2(struct spi_nor *nor, const u8 *sr2)
1069 {
1070 	int ret;
1071 
1072 	ret = spi_nor_write_enable(nor);
1073 	if (ret)
1074 		return ret;
1075 
1076 	if (nor->spimem) {
1077 		struct spi_mem_op op =
1078 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WRSR2, 0),
1079 				   SPI_MEM_OP_NO_ADDR,
1080 				   SPI_MEM_OP_NO_DUMMY,
1081 				   SPI_MEM_OP_DATA_OUT(1, sr2, 0));
1082 
1083 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1084 
1085 		ret = spi_mem_exec_op(nor->spimem, &op);
1086 	} else {
1087 		ret = spi_nor_controller_ops_write_reg(nor, SPINOR_OP_WRSR2,
1088 						       sr2, 1);
1089 	}
1090 
1091 	if (ret) {
1092 		dev_dbg(nor->dev, "error %d writing SR2\n", ret);
1093 		return ret;
1094 	}
1095 
1096 	return spi_nor_wait_till_ready(nor);
1097 }
1098 
1099 /**
1100  * spi_nor_read_sr2() - Read the Status Register 2 using the
1101  * SPINOR_OP_RDSR2 (3fh) command.
1102  * @nor:	pointer to 'struct spi_nor'.
1103  * @sr2:	pointer to DMA-able buffer where the value of the
1104  *		Status Register 2 will be written.
1105  *
1106  * Return: 0 on success, -errno otherwise.
1107  */
1108 static int spi_nor_read_sr2(struct spi_nor *nor, u8 *sr2)
1109 {
1110 	int ret;
1111 
1112 	if (nor->spimem) {
1113 		struct spi_mem_op op =
1114 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDSR2, 0),
1115 				   SPI_MEM_OP_NO_ADDR,
1116 				   SPI_MEM_OP_NO_DUMMY,
1117 				   SPI_MEM_OP_DATA_IN(1, sr2, 0));
1118 
1119 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
1120 
1121 		ret = spi_mem_exec_op(nor->spimem, &op);
1122 	} else {
1123 		ret = spi_nor_controller_ops_read_reg(nor, SPINOR_OP_RDSR2, sr2,
1124 						      1);
1125 	}
1126 
1127 	if (ret)
1128 		dev_dbg(nor->dev, "error %d reading SR2\n", ret);
1129 
1130 	return ret;
1131 }
1132 
1133 /**
1134  * spi_nor_erase_chip() - Erase the entire flash memory.
1135  * @nor:	pointer to 'struct spi_nor'.
1136  *
1137  * Return: 0 on success, -errno otherwise.
1138  */
1139 static int spi_nor_erase_chip(struct spi_nor *nor)
1140 {
1141 	int ret;
1142 
1143 	dev_dbg(nor->dev, " %lldKiB\n", (long long)(nor->mtd.size >> 10));
1144 
1145 	if (nor->spimem) {
1146 		struct spi_mem_op op =
1147 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_CHIP_ERASE, 0),
1148 				   SPI_MEM_OP_NO_ADDR,
1149 				   SPI_MEM_OP_NO_DUMMY,
1150 				   SPI_MEM_OP_NO_DATA);
1151 
1152 		spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
1153 
1154 		ret = spi_mem_exec_op(nor->spimem, &op);
1155 	} else {
1156 		ret = spi_nor_controller_ops_write_reg(nor,
1157 						       SPINOR_OP_CHIP_ERASE,
1158 						       NULL, 0);
1159 	}
1160 
1161 	if (ret)
1162 		dev_dbg(nor->dev, "error %d erasing chip\n", ret);
1163 
1164 	return ret;
1165 }
1166 
1167 static u8 spi_nor_convert_opcode(u8 opcode, const u8 table[][2], size_t size)
1168 {
1169 	size_t i;
1170 
1171 	for (i = 0; i < size; i++)
1172 		if (table[i][0] == opcode)
1173 			return table[i][1];
1174 
1175 	/* No conversion found, keep input op code. */
1176 	return opcode;
1177 }
1178 
1179 u8 spi_nor_convert_3to4_read(u8 opcode)
1180 {
1181 	static const u8 spi_nor_3to4_read[][2] = {
1182 		{ SPINOR_OP_READ,	SPINOR_OP_READ_4B },
1183 		{ SPINOR_OP_READ_FAST,	SPINOR_OP_READ_FAST_4B },
1184 		{ SPINOR_OP_READ_1_1_2,	SPINOR_OP_READ_1_1_2_4B },
1185 		{ SPINOR_OP_READ_1_2_2,	SPINOR_OP_READ_1_2_2_4B },
1186 		{ SPINOR_OP_READ_1_1_4,	SPINOR_OP_READ_1_1_4_4B },
1187 		{ SPINOR_OP_READ_1_4_4,	SPINOR_OP_READ_1_4_4_4B },
1188 		{ SPINOR_OP_READ_1_1_8,	SPINOR_OP_READ_1_1_8_4B },
1189 		{ SPINOR_OP_READ_1_8_8,	SPINOR_OP_READ_1_8_8_4B },
1190 
1191 		{ SPINOR_OP_READ_1_1_1_DTR,	SPINOR_OP_READ_1_1_1_DTR_4B },
1192 		{ SPINOR_OP_READ_1_2_2_DTR,	SPINOR_OP_READ_1_2_2_DTR_4B },
1193 		{ SPINOR_OP_READ_1_4_4_DTR,	SPINOR_OP_READ_1_4_4_DTR_4B },
1194 	};
1195 
1196 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_read,
1197 				      ARRAY_SIZE(spi_nor_3to4_read));
1198 }
1199 
1200 static u8 spi_nor_convert_3to4_program(u8 opcode)
1201 {
1202 	static const u8 spi_nor_3to4_program[][2] = {
1203 		{ SPINOR_OP_PP,		SPINOR_OP_PP_4B },
1204 		{ SPINOR_OP_PP_1_1_4,	SPINOR_OP_PP_1_1_4_4B },
1205 		{ SPINOR_OP_PP_1_4_4,	SPINOR_OP_PP_1_4_4_4B },
1206 		{ SPINOR_OP_PP_1_1_8,	SPINOR_OP_PP_1_1_8_4B },
1207 		{ SPINOR_OP_PP_1_8_8,	SPINOR_OP_PP_1_8_8_4B },
1208 	};
1209 
1210 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_program,
1211 				      ARRAY_SIZE(spi_nor_3to4_program));
1212 }
1213 
1214 static u8 spi_nor_convert_3to4_erase(u8 opcode)
1215 {
1216 	static const u8 spi_nor_3to4_erase[][2] = {
1217 		{ SPINOR_OP_BE_4K,	SPINOR_OP_BE_4K_4B },
1218 		{ SPINOR_OP_BE_32K,	SPINOR_OP_BE_32K_4B },
1219 		{ SPINOR_OP_SE,		SPINOR_OP_SE_4B },
1220 	};
1221 
1222 	return spi_nor_convert_opcode(opcode, spi_nor_3to4_erase,
1223 				      ARRAY_SIZE(spi_nor_3to4_erase));
1224 }
1225 
1226 static bool spi_nor_has_uniform_erase(const struct spi_nor *nor)
1227 {
1228 	return !!nor->params->erase_map.uniform_erase_type;
1229 }
1230 
1231 static void spi_nor_set_4byte_opcodes(struct spi_nor *nor)
1232 {
1233 	nor->read_opcode = spi_nor_convert_3to4_read(nor->read_opcode);
1234 	nor->program_opcode = spi_nor_convert_3to4_program(nor->program_opcode);
1235 	nor->erase_opcode = spi_nor_convert_3to4_erase(nor->erase_opcode);
1236 
1237 	if (!spi_nor_has_uniform_erase(nor)) {
1238 		struct spi_nor_erase_map *map = &nor->params->erase_map;
1239 		struct spi_nor_erase_type *erase;
1240 		int i;
1241 
1242 		for (i = 0; i < SNOR_ERASE_TYPE_MAX; i++) {
1243 			erase = &map->erase_type[i];
1244 			erase->opcode =
1245 				spi_nor_convert_3to4_erase(erase->opcode);
1246 		}
1247 	}
1248 }
1249 
1250 int spi_nor_lock_and_prep(struct spi_nor *nor)
1251 {
1252 	int ret = 0;
1253 
1254 	mutex_lock(&nor->lock);
1255 
1256 	if (nor->controller_ops &&  nor->controller_ops->prepare) {
1257 		ret = nor->controller_ops->prepare(nor);
1258 		if (ret) {
1259 			mutex_unlock(&nor->lock);
1260 			return ret;
1261 		}
1262 	}
1263 	return ret;
1264 }
1265 
1266 void spi_nor_unlock_and_unprep(struct spi_nor *nor)
1267 {
1268 	if (nor->controller_ops && nor->controller_ops->unprepare)
1269 		nor->controller_ops->unprepare(nor);
1270 	mutex_unlock(&nor->lock);
1271 }
1272 
1273 static u32 spi_nor_convert_addr(struct spi_nor *nor, loff_t addr)
1274 {
1275 	if (!nor->params->convert_addr)
1276 		return addr;
1277 
1278 	return nor->params->convert_addr(nor, addr);
1279 }
1280 
1281 /*
1282  * Initiate the erasure of a single sector
1283  */
1284 static int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
1285 {
1286 	int i;
1287 
1288 	addr = spi_nor_convert_addr(nor, addr);
1289 
1290 	if (nor->spimem) {
1291 		struct spi_mem_op op =
1292 			SPI_MEM_OP(SPI_MEM_OP_CMD(nor->erase_opcode, 0),
1293 				   SPI_MEM_OP_ADDR(nor->addr_width, addr, 0),
1294 				   SPI_MEM_OP_NO_DUMMY,
1295 				   SPI_MEM_OP_NO_DATA);
1296 
1297 		spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
1298 
1299 		return spi_mem_exec_op(nor->spimem, &op);
1300 	} else if (nor->controller_ops->erase) {
1301 		return spi_nor_controller_ops_erase(nor, addr);
1302 	}
1303 
1304 	/*
1305 	 * Default implementation, if driver doesn't have a specialized HW
1306 	 * control
1307 	 */
1308 	for (i = nor->addr_width - 1; i >= 0; i--) {
1309 		nor->bouncebuf[i] = addr & 0xff;
1310 		addr >>= 8;
1311 	}
1312 
1313 	return spi_nor_controller_ops_write_reg(nor, nor->erase_opcode,
1314 						nor->bouncebuf, nor->addr_width);
1315 }
1316 
1317 /**
1318  * spi_nor_div_by_erase_size() - calculate remainder and update new dividend
1319  * @erase:	pointer to a structure that describes a SPI NOR erase type
1320  * @dividend:	dividend value
1321  * @remainder:	pointer to u32 remainder (will be updated)
1322  *
1323  * Return: the result of the division
1324  */
1325 static u64 spi_nor_div_by_erase_size(const struct spi_nor_erase_type *erase,
1326 				     u64 dividend, u32 *remainder)
1327 {
1328 	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
1329 	*remainder = (u32)dividend & erase->size_mask;
1330 	return dividend >> erase->size_shift;
1331 }
1332 
1333 /**
1334  * spi_nor_find_best_erase_type() - find the best erase type for the given
1335  *				    offset in the serial flash memory and the
1336  *				    number of bytes to erase. The region in
1337  *				    which the address fits is expected to be
1338  *				    provided.
1339  * @map:	the erase map of the SPI NOR
1340  * @region:	pointer to a structure that describes a SPI NOR erase region
1341  * @addr:	offset in the serial flash memory
1342  * @len:	number of bytes to erase
1343  *
1344  * Return: a pointer to the best fitted erase type, NULL otherwise.
1345  */
1346 static const struct spi_nor_erase_type *
1347 spi_nor_find_best_erase_type(const struct spi_nor_erase_map *map,
1348 			     const struct spi_nor_erase_region *region,
1349 			     u64 addr, u32 len)
1350 {
1351 	const struct spi_nor_erase_type *erase;
1352 	u32 rem;
1353 	int i;
1354 	u8 erase_mask = region->offset & SNOR_ERASE_TYPE_MASK;
1355 
1356 	/*
1357 	 * Erase types are ordered by size, with the smallest erase type at
1358 	 * index 0.
1359 	 */
1360 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
1361 		/* Does the erase region support the tested erase type? */
1362 		if (!(erase_mask & BIT(i)))
1363 			continue;
1364 
1365 		erase = &map->erase_type[i];
1366 
1367 		/* Don't erase more than what the user has asked for. */
1368 		if (erase->size > len)
1369 			continue;
1370 
1371 		/* Alignment is not mandatory for overlaid regions */
1372 		if (region->offset & SNOR_OVERLAID_REGION)
1373 			return erase;
1374 
1375 		spi_nor_div_by_erase_size(erase, addr, &rem);
1376 		if (rem)
1377 			continue;
1378 		else
1379 			return erase;
1380 	}
1381 
1382 	return NULL;
1383 }
1384 
1385 static u64 spi_nor_region_is_last(const struct spi_nor_erase_region *region)
1386 {
1387 	return region->offset & SNOR_LAST_REGION;
1388 }
1389 
1390 static u64 spi_nor_region_end(const struct spi_nor_erase_region *region)
1391 {
1392 	return (region->offset & ~SNOR_ERASE_FLAGS_MASK) + region->size;
1393 }
1394 
1395 /**
1396  * spi_nor_region_next() - get the next spi nor region
1397  * @region:	pointer to a structure that describes a SPI NOR erase region
1398  *
1399  * Return: the next spi nor region or NULL if last region.
1400  */
1401 struct spi_nor_erase_region *
1402 spi_nor_region_next(struct spi_nor_erase_region *region)
1403 {
1404 	if (spi_nor_region_is_last(region))
1405 		return NULL;
1406 	region++;
1407 	return region;
1408 }
1409 
1410 /**
1411  * spi_nor_find_erase_region() - find the region of the serial flash memory in
1412  *				 which the offset fits
1413  * @map:	the erase map of the SPI NOR
1414  * @addr:	offset in the serial flash memory
1415  *
1416  * Return: a pointer to the spi_nor_erase_region struct, ERR_PTR(-errno)
1417  *	   otherwise.
1418  */
1419 static struct spi_nor_erase_region *
1420 spi_nor_find_erase_region(const struct spi_nor_erase_map *map, u64 addr)
1421 {
1422 	struct spi_nor_erase_region *region = map->regions;
1423 	u64 region_start = region->offset & ~SNOR_ERASE_FLAGS_MASK;
1424 	u64 region_end = region_start + region->size;
1425 
1426 	while (addr < region_start || addr >= region_end) {
1427 		region = spi_nor_region_next(region);
1428 		if (!region)
1429 			return ERR_PTR(-EINVAL);
1430 
1431 		region_start = region->offset & ~SNOR_ERASE_FLAGS_MASK;
1432 		region_end = region_start + region->size;
1433 	}
1434 
1435 	return region;
1436 }
1437 
1438 /**
1439  * spi_nor_init_erase_cmd() - initialize an erase command
1440  * @region:	pointer to a structure that describes a SPI NOR erase region
1441  * @erase:	pointer to a structure that describes a SPI NOR erase type
1442  *
1443  * Return: the pointer to the allocated erase command, ERR_PTR(-errno)
1444  *	   otherwise.
1445  */
1446 static struct spi_nor_erase_command *
1447 spi_nor_init_erase_cmd(const struct spi_nor_erase_region *region,
1448 		       const struct spi_nor_erase_type *erase)
1449 {
1450 	struct spi_nor_erase_command *cmd;
1451 
1452 	cmd = kmalloc(sizeof(*cmd), GFP_KERNEL);
1453 	if (!cmd)
1454 		return ERR_PTR(-ENOMEM);
1455 
1456 	INIT_LIST_HEAD(&cmd->list);
1457 	cmd->opcode = erase->opcode;
1458 	cmd->count = 1;
1459 
1460 	if (region->offset & SNOR_OVERLAID_REGION)
1461 		cmd->size = region->size;
1462 	else
1463 		cmd->size = erase->size;
1464 
1465 	return cmd;
1466 }
1467 
1468 /**
1469  * spi_nor_destroy_erase_cmd_list() - destroy erase command list
1470  * @erase_list:	list of erase commands
1471  */
1472 static void spi_nor_destroy_erase_cmd_list(struct list_head *erase_list)
1473 {
1474 	struct spi_nor_erase_command *cmd, *next;
1475 
1476 	list_for_each_entry_safe(cmd, next, erase_list, list) {
1477 		list_del(&cmd->list);
1478 		kfree(cmd);
1479 	}
1480 }
1481 
1482 /**
1483  * spi_nor_init_erase_cmd_list() - initialize erase command list
1484  * @nor:	pointer to a 'struct spi_nor'
1485  * @erase_list:	list of erase commands to be executed once we validate that the
1486  *		erase can be performed
1487  * @addr:	offset in the serial flash memory
1488  * @len:	number of bytes to erase
1489  *
1490  * Builds the list of best fitted erase commands and verifies if the erase can
1491  * be performed.
1492  *
1493  * Return: 0 on success, -errno otherwise.
1494  */
1495 static int spi_nor_init_erase_cmd_list(struct spi_nor *nor,
1496 				       struct list_head *erase_list,
1497 				       u64 addr, u32 len)
1498 {
1499 	const struct spi_nor_erase_map *map = &nor->params->erase_map;
1500 	const struct spi_nor_erase_type *erase, *prev_erase = NULL;
1501 	struct spi_nor_erase_region *region;
1502 	struct spi_nor_erase_command *cmd = NULL;
1503 	u64 region_end;
1504 	int ret = -EINVAL;
1505 
1506 	region = spi_nor_find_erase_region(map, addr);
1507 	if (IS_ERR(region))
1508 		return PTR_ERR(region);
1509 
1510 	region_end = spi_nor_region_end(region);
1511 
1512 	while (len) {
1513 		erase = spi_nor_find_best_erase_type(map, region, addr, len);
1514 		if (!erase)
1515 			goto destroy_erase_cmd_list;
1516 
1517 		if (prev_erase != erase ||
1518 		    region->offset & SNOR_OVERLAID_REGION) {
1519 			cmd = spi_nor_init_erase_cmd(region, erase);
1520 			if (IS_ERR(cmd)) {
1521 				ret = PTR_ERR(cmd);
1522 				goto destroy_erase_cmd_list;
1523 			}
1524 
1525 			list_add_tail(&cmd->list, erase_list);
1526 		} else {
1527 			cmd->count++;
1528 		}
1529 
1530 		addr += cmd->size;
1531 		len -= cmd->size;
1532 
1533 		if (len && addr >= region_end) {
1534 			region = spi_nor_region_next(region);
1535 			if (!region)
1536 				goto destroy_erase_cmd_list;
1537 			region_end = spi_nor_region_end(region);
1538 		}
1539 
1540 		prev_erase = erase;
1541 	}
1542 
1543 	return 0;
1544 
1545 destroy_erase_cmd_list:
1546 	spi_nor_destroy_erase_cmd_list(erase_list);
1547 	return ret;
1548 }
1549 
1550 /**
1551  * spi_nor_erase_multi_sectors() - perform a non-uniform erase
1552  * @nor:	pointer to a 'struct spi_nor'
1553  * @addr:	offset in the serial flash memory
1554  * @len:	number of bytes to erase
1555  *
1556  * Build a list of best fitted erase commands and execute it once we validate
1557  * that the erase can be performed.
1558  *
1559  * Return: 0 on success, -errno otherwise.
1560  */
1561 static int spi_nor_erase_multi_sectors(struct spi_nor *nor, u64 addr, u32 len)
1562 {
1563 	LIST_HEAD(erase_list);
1564 	struct spi_nor_erase_command *cmd, *next;
1565 	int ret;
1566 
1567 	ret = spi_nor_init_erase_cmd_list(nor, &erase_list, addr, len);
1568 	if (ret)
1569 		return ret;
1570 
1571 	list_for_each_entry_safe(cmd, next, &erase_list, list) {
1572 		nor->erase_opcode = cmd->opcode;
1573 		while (cmd->count) {
1574 			ret = spi_nor_write_enable(nor);
1575 			if (ret)
1576 				goto destroy_erase_cmd_list;
1577 
1578 			ret = spi_nor_erase_sector(nor, addr);
1579 			if (ret)
1580 				goto destroy_erase_cmd_list;
1581 
1582 			addr += cmd->size;
1583 			cmd->count--;
1584 
1585 			ret = spi_nor_wait_till_ready(nor);
1586 			if (ret)
1587 				goto destroy_erase_cmd_list;
1588 		}
1589 		list_del(&cmd->list);
1590 		kfree(cmd);
1591 	}
1592 
1593 	return 0;
1594 
1595 destroy_erase_cmd_list:
1596 	spi_nor_destroy_erase_cmd_list(&erase_list);
1597 	return ret;
1598 }
1599 
1600 /*
1601  * Erase an address range on the nor chip.  The address range may extend
1602  * one or more erase sectors. Return an error if there is a problem erasing.
1603  */
1604 static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr)
1605 {
1606 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
1607 	u32 addr, len;
1608 	uint32_t rem;
1609 	int ret;
1610 
1611 	dev_dbg(nor->dev, "at 0x%llx, len %lld\n", (long long)instr->addr,
1612 			(long long)instr->len);
1613 
1614 	if (spi_nor_has_uniform_erase(nor)) {
1615 		div_u64_rem(instr->len, mtd->erasesize, &rem);
1616 		if (rem)
1617 			return -EINVAL;
1618 	}
1619 
1620 	addr = instr->addr;
1621 	len = instr->len;
1622 
1623 	ret = spi_nor_lock_and_prep(nor);
1624 	if (ret)
1625 		return ret;
1626 
1627 	/* whole-chip erase? */
1628 	if (len == mtd->size && !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) {
1629 		unsigned long timeout;
1630 
1631 		ret = spi_nor_write_enable(nor);
1632 		if (ret)
1633 			goto erase_err;
1634 
1635 		ret = spi_nor_erase_chip(nor);
1636 		if (ret)
1637 			goto erase_err;
1638 
1639 		/*
1640 		 * Scale the timeout linearly with the size of the flash, with
1641 		 * a minimum calibrated to an old 2MB flash. We could try to
1642 		 * pull these from CFI/SFDP, but these values should be good
1643 		 * enough for now.
1644 		 */
1645 		timeout = max(CHIP_ERASE_2MB_READY_WAIT_JIFFIES,
1646 			      CHIP_ERASE_2MB_READY_WAIT_JIFFIES *
1647 			      (unsigned long)(mtd->size / SZ_2M));
1648 		ret = spi_nor_wait_till_ready_with_timeout(nor, timeout);
1649 		if (ret)
1650 			goto erase_err;
1651 
1652 	/* REVISIT in some cases we could speed up erasing large regions
1653 	 * by using SPINOR_OP_SE instead of SPINOR_OP_BE_4K.  We may have set up
1654 	 * to use "small sector erase", but that's not always optimal.
1655 	 */
1656 
1657 	/* "sector"-at-a-time erase */
1658 	} else if (spi_nor_has_uniform_erase(nor)) {
1659 		while (len) {
1660 			ret = spi_nor_write_enable(nor);
1661 			if (ret)
1662 				goto erase_err;
1663 
1664 			ret = spi_nor_erase_sector(nor, addr);
1665 			if (ret)
1666 				goto erase_err;
1667 
1668 			addr += mtd->erasesize;
1669 			len -= mtd->erasesize;
1670 
1671 			ret = spi_nor_wait_till_ready(nor);
1672 			if (ret)
1673 				goto erase_err;
1674 		}
1675 
1676 	/* erase multiple sectors */
1677 	} else {
1678 		ret = spi_nor_erase_multi_sectors(nor, addr, len);
1679 		if (ret)
1680 			goto erase_err;
1681 	}
1682 
1683 	ret = spi_nor_write_disable(nor);
1684 
1685 erase_err:
1686 	spi_nor_unlock_and_unprep(nor);
1687 
1688 	return ret;
1689 }
1690 
1691 static u8 spi_nor_get_sr_bp_mask(struct spi_nor *nor)
1692 {
1693 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
1694 
1695 	if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6)
1696 		return mask | SR_BP3_BIT6;
1697 
1698 	if (nor->flags & SNOR_F_HAS_4BIT_BP)
1699 		return mask | SR_BP3;
1700 
1701 	return mask;
1702 }
1703 
1704 static u8 spi_nor_get_sr_tb_mask(struct spi_nor *nor)
1705 {
1706 	if (nor->flags & SNOR_F_HAS_SR_TB_BIT6)
1707 		return SR_TB_BIT6;
1708 	else
1709 		return SR_TB_BIT5;
1710 }
1711 
1712 static u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor)
1713 {
1714 	unsigned int bp_slots, bp_slots_needed;
1715 	u8 mask = spi_nor_get_sr_bp_mask(nor);
1716 
1717 	/* Reserved one for "protect none" and one for "protect all". */
1718 	bp_slots = (1 << hweight8(mask)) - 2;
1719 	bp_slots_needed = ilog2(nor->info->n_sectors);
1720 
1721 	if (bp_slots_needed > bp_slots)
1722 		return nor->info->sector_size <<
1723 			(bp_slots_needed - bp_slots);
1724 	else
1725 		return nor->info->sector_size;
1726 }
1727 
1728 static void spi_nor_get_locked_range_sr(struct spi_nor *nor, u8 sr, loff_t *ofs,
1729 					uint64_t *len)
1730 {
1731 	struct mtd_info *mtd = &nor->mtd;
1732 	u64 min_prot_len;
1733 	u8 mask = spi_nor_get_sr_bp_mask(nor);
1734 	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
1735 	u8 bp, val = sr & mask;
1736 
1737 	if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3_BIT6)
1738 		val = (val & ~SR_BP3_BIT6) | SR_BP3;
1739 
1740 	bp = val >> SR_BP_SHIFT;
1741 
1742 	if (!bp) {
1743 		/* No protection */
1744 		*ofs = 0;
1745 		*len = 0;
1746 		return;
1747 	}
1748 
1749 	min_prot_len = spi_nor_get_min_prot_length_sr(nor);
1750 	*len = min_prot_len << (bp - 1);
1751 
1752 	if (*len > mtd->size)
1753 		*len = mtd->size;
1754 
1755 	if (nor->flags & SNOR_F_HAS_SR_TB && sr & tb_mask)
1756 		*ofs = 0;
1757 	else
1758 		*ofs = mtd->size - *len;
1759 }
1760 
1761 /*
1762  * Return 1 if the entire region is locked (if @locked is true) or unlocked (if
1763  * @locked is false); 0 otherwise
1764  */
1765 static int spi_nor_check_lock_status_sr(struct spi_nor *nor, loff_t ofs,
1766 					uint64_t len, u8 sr, bool locked)
1767 {
1768 	loff_t lock_offs;
1769 	uint64_t lock_len;
1770 
1771 	if (!len)
1772 		return 1;
1773 
1774 	spi_nor_get_locked_range_sr(nor, sr, &lock_offs, &lock_len);
1775 
1776 	if (locked)
1777 		/* Requested range is a sub-range of locked range */
1778 		return (ofs + len <= lock_offs + lock_len) && (ofs >= lock_offs);
1779 	else
1780 		/* Requested range does not overlap with locked range */
1781 		return (ofs >= lock_offs + lock_len) || (ofs + len <= lock_offs);
1782 }
1783 
1784 static int spi_nor_is_locked_sr(struct spi_nor *nor, loff_t ofs, uint64_t len,
1785 				u8 sr)
1786 {
1787 	return spi_nor_check_lock_status_sr(nor, ofs, len, sr, true);
1788 }
1789 
1790 static int spi_nor_is_unlocked_sr(struct spi_nor *nor, loff_t ofs, uint64_t len,
1791 				  u8 sr)
1792 {
1793 	return spi_nor_check_lock_status_sr(nor, ofs, len, sr, false);
1794 }
1795 
1796 /*
1797  * Lock a region of the flash. Compatible with ST Micro and similar flash.
1798  * Supports the block protection bits BP{0,1,2}/BP{0,1,2,3} in the status
1799  * register
1800  * (SR). Does not support these features found in newer SR bitfields:
1801  *   - SEC: sector/block protect - only handle SEC=0 (block protect)
1802  *   - CMP: complement protect - only support CMP=0 (range is not complemented)
1803  *
1804  * Support for the following is provided conditionally for some flash:
1805  *   - TB: top/bottom protect
1806  *
1807  * Sample table portion for 8MB flash (Winbond w25q64fw):
1808  *
1809  *   SEC  |  TB   |  BP2  |  BP1  |  BP0  |  Prot Length  | Protected Portion
1810  *  --------------------------------------------------------------------------
1811  *    X   |   X   |   0   |   0   |   0   |  NONE         | NONE
1812  *    0   |   0   |   0   |   0   |   1   |  128 KB       | Upper 1/64
1813  *    0   |   0   |   0   |   1   |   0   |  256 KB       | Upper 1/32
1814  *    0   |   0   |   0   |   1   |   1   |  512 KB       | Upper 1/16
1815  *    0   |   0   |   1   |   0   |   0   |  1 MB         | Upper 1/8
1816  *    0   |   0   |   1   |   0   |   1   |  2 MB         | Upper 1/4
1817  *    0   |   0   |   1   |   1   |   0   |  4 MB         | Upper 1/2
1818  *    X   |   X   |   1   |   1   |   1   |  8 MB         | ALL
1819  *  ------|-------|-------|-------|-------|---------------|-------------------
1820  *    0   |   1   |   0   |   0   |   1   |  128 KB       | Lower 1/64
1821  *    0   |   1   |   0   |   1   |   0   |  256 KB       | Lower 1/32
1822  *    0   |   1   |   0   |   1   |   1   |  512 KB       | Lower 1/16
1823  *    0   |   1   |   1   |   0   |   0   |  1 MB         | Lower 1/8
1824  *    0   |   1   |   1   |   0   |   1   |  2 MB         | Lower 1/4
1825  *    0   |   1   |   1   |   1   |   0   |  4 MB         | Lower 1/2
1826  *
1827  * Returns negative on errors, 0 on success.
1828  */
1829 static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
1830 {
1831 	struct mtd_info *mtd = &nor->mtd;
1832 	u64 min_prot_len;
1833 	int ret, status_old, status_new;
1834 	u8 mask = spi_nor_get_sr_bp_mask(nor);
1835 	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
1836 	u8 pow, val;
1837 	loff_t lock_len;
1838 	bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;
1839 	bool use_top;
1840 
1841 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
1842 	if (ret)
1843 		return ret;
1844 
1845 	status_old = nor->bouncebuf[0];
1846 
1847 	/* If nothing in our range is unlocked, we don't need to do anything */
1848 	if (spi_nor_is_locked_sr(nor, ofs, len, status_old))
1849 		return 0;
1850 
1851 	/* If anything below us is unlocked, we can't use 'bottom' protection */
1852 	if (!spi_nor_is_locked_sr(nor, 0, ofs, status_old))
1853 		can_be_bottom = false;
1854 
1855 	/* If anything above us is unlocked, we can't use 'top' protection */
1856 	if (!spi_nor_is_locked_sr(nor, ofs + len, mtd->size - (ofs + len),
1857 				  status_old))
1858 		can_be_top = false;
1859 
1860 	if (!can_be_bottom && !can_be_top)
1861 		return -EINVAL;
1862 
1863 	/* Prefer top, if both are valid */
1864 	use_top = can_be_top;
1865 
1866 	/* lock_len: length of region that should end up locked */
1867 	if (use_top)
1868 		lock_len = mtd->size - ofs;
1869 	else
1870 		lock_len = ofs + len;
1871 
1872 	if (lock_len == mtd->size) {
1873 		val = mask;
1874 	} else {
1875 		min_prot_len = spi_nor_get_min_prot_length_sr(nor);
1876 		pow = ilog2(lock_len) - ilog2(min_prot_len) + 1;
1877 		val = pow << SR_BP_SHIFT;
1878 
1879 		if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3)
1880 			val = (val & ~SR_BP3) | SR_BP3_BIT6;
1881 
1882 		if (val & ~mask)
1883 			return -EINVAL;
1884 
1885 		/* Don't "lock" with no region! */
1886 		if (!(val & mask))
1887 			return -EINVAL;
1888 	}
1889 
1890 	status_new = (status_old & ~mask & ~tb_mask) | val;
1891 
1892 	/* Disallow further writes if WP pin is asserted */
1893 	status_new |= SR_SRWD;
1894 
1895 	if (!use_top)
1896 		status_new |= tb_mask;
1897 
1898 	/* Don't bother if they're the same */
1899 	if (status_new == status_old)
1900 		return 0;
1901 
1902 	/* Only modify protection if it will not unlock other areas */
1903 	if ((status_new & mask) < (status_old & mask))
1904 		return -EINVAL;
1905 
1906 	return spi_nor_write_sr_and_check(nor, status_new);
1907 }
1908 
1909 /*
1910  * Unlock a region of the flash. See spi_nor_sr_lock() for more info
1911  *
1912  * Returns negative on errors, 0 on success.
1913  */
1914 static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
1915 {
1916 	struct mtd_info *mtd = &nor->mtd;
1917 	u64 min_prot_len;
1918 	int ret, status_old, status_new;
1919 	u8 mask = spi_nor_get_sr_bp_mask(nor);
1920 	u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
1921 	u8 pow, val;
1922 	loff_t lock_len;
1923 	bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;
1924 	bool use_top;
1925 
1926 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
1927 	if (ret)
1928 		return ret;
1929 
1930 	status_old = nor->bouncebuf[0];
1931 
1932 	/* If nothing in our range is locked, we don't need to do anything */
1933 	if (spi_nor_is_unlocked_sr(nor, ofs, len, status_old))
1934 		return 0;
1935 
1936 	/* If anything below us is locked, we can't use 'top' protection */
1937 	if (!spi_nor_is_unlocked_sr(nor, 0, ofs, status_old))
1938 		can_be_top = false;
1939 
1940 	/* If anything above us is locked, we can't use 'bottom' protection */
1941 	if (!spi_nor_is_unlocked_sr(nor, ofs + len, mtd->size - (ofs + len),
1942 				    status_old))
1943 		can_be_bottom = false;
1944 
1945 	if (!can_be_bottom && !can_be_top)
1946 		return -EINVAL;
1947 
1948 	/* Prefer top, if both are valid */
1949 	use_top = can_be_top;
1950 
1951 	/* lock_len: length of region that should remain locked */
1952 	if (use_top)
1953 		lock_len = mtd->size - (ofs + len);
1954 	else
1955 		lock_len = ofs;
1956 
1957 	if (lock_len == 0) {
1958 		val = 0; /* fully unlocked */
1959 	} else {
1960 		min_prot_len = spi_nor_get_min_prot_length_sr(nor);
1961 		pow = ilog2(lock_len) - ilog2(min_prot_len) + 1;
1962 		val = pow << SR_BP_SHIFT;
1963 
1964 		if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3)
1965 			val = (val & ~SR_BP3) | SR_BP3_BIT6;
1966 
1967 		/* Some power-of-two sizes are not supported */
1968 		if (val & ~mask)
1969 			return -EINVAL;
1970 	}
1971 
1972 	status_new = (status_old & ~mask & ~tb_mask) | val;
1973 
1974 	/* Don't protect status register if we're fully unlocked */
1975 	if (lock_len == 0)
1976 		status_new &= ~SR_SRWD;
1977 
1978 	if (!use_top)
1979 		status_new |= tb_mask;
1980 
1981 	/* Don't bother if they're the same */
1982 	if (status_new == status_old)
1983 		return 0;
1984 
1985 	/* Only modify protection if it will not lock other areas */
1986 	if ((status_new & mask) > (status_old & mask))
1987 		return -EINVAL;
1988 
1989 	return spi_nor_write_sr_and_check(nor, status_new);
1990 }
1991 
1992 /*
1993  * Check if a region of the flash is (completely) locked. See spi_nor_sr_lock()
1994  * for more info.
1995  *
1996  * Returns 1 if entire region is locked, 0 if any portion is unlocked, and
1997  * negative on errors.
1998  */
1999 static int spi_nor_sr_is_locked(struct spi_nor *nor, loff_t ofs, uint64_t len)
2000 {
2001 	int ret;
2002 
2003 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
2004 	if (ret)
2005 		return ret;
2006 
2007 	return spi_nor_is_locked_sr(nor, ofs, len, nor->bouncebuf[0]);
2008 }
2009 
2010 static const struct spi_nor_locking_ops spi_nor_sr_locking_ops = {
2011 	.lock = spi_nor_sr_lock,
2012 	.unlock = spi_nor_sr_unlock,
2013 	.is_locked = spi_nor_sr_is_locked,
2014 };
2015 
2016 static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
2017 {
2018 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2019 	int ret;
2020 
2021 	ret = spi_nor_lock_and_prep(nor);
2022 	if (ret)
2023 		return ret;
2024 
2025 	ret = nor->params->locking_ops->lock(nor, ofs, len);
2026 
2027 	spi_nor_unlock_and_unprep(nor);
2028 	return ret;
2029 }
2030 
2031 static int spi_nor_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
2032 {
2033 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2034 	int ret;
2035 
2036 	ret = spi_nor_lock_and_prep(nor);
2037 	if (ret)
2038 		return ret;
2039 
2040 	ret = nor->params->locking_ops->unlock(nor, ofs, len);
2041 
2042 	spi_nor_unlock_and_unprep(nor);
2043 	return ret;
2044 }
2045 
2046 static int spi_nor_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
2047 {
2048 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2049 	int ret;
2050 
2051 	ret = spi_nor_lock_and_prep(nor);
2052 	if (ret)
2053 		return ret;
2054 
2055 	ret = nor->params->locking_ops->is_locked(nor, ofs, len);
2056 
2057 	spi_nor_unlock_and_unprep(nor);
2058 	return ret;
2059 }
2060 
2061 /**
2062  * spi_nor_sr1_bit6_quad_enable() - Set the Quad Enable BIT(6) in the Status
2063  * Register 1.
2064  * @nor:	pointer to a 'struct spi_nor'
2065  *
2066  * Bit 6 of the Status Register 1 is the QE bit for Macronix like QSPI memories.
2067  *
2068  * Return: 0 on success, -errno otherwise.
2069  */
2070 int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor)
2071 {
2072 	int ret;
2073 
2074 	ret = spi_nor_read_sr(nor, nor->bouncebuf);
2075 	if (ret)
2076 		return ret;
2077 
2078 	if (nor->bouncebuf[0] & SR1_QUAD_EN_BIT6)
2079 		return 0;
2080 
2081 	nor->bouncebuf[0] |= SR1_QUAD_EN_BIT6;
2082 
2083 	return spi_nor_write_sr1_and_check(nor, nor->bouncebuf[0]);
2084 }
2085 
2086 /**
2087  * spi_nor_sr2_bit1_quad_enable() - set the Quad Enable BIT(1) in the Status
2088  * Register 2.
2089  * @nor:       pointer to a 'struct spi_nor'.
2090  *
2091  * Bit 1 of the Status Register 2 is the QE bit for Spansion like QSPI memories.
2092  *
2093  * Return: 0 on success, -errno otherwise.
2094  */
2095 int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor)
2096 {
2097 	int ret;
2098 
2099 	if (nor->flags & SNOR_F_NO_READ_CR)
2100 		return spi_nor_write_16bit_cr_and_check(nor, SR2_QUAD_EN_BIT1);
2101 
2102 	ret = spi_nor_read_cr(nor, nor->bouncebuf);
2103 	if (ret)
2104 		return ret;
2105 
2106 	if (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)
2107 		return 0;
2108 
2109 	nor->bouncebuf[0] |= SR2_QUAD_EN_BIT1;
2110 
2111 	return spi_nor_write_16bit_cr_and_check(nor, nor->bouncebuf[0]);
2112 }
2113 
2114 /**
2115  * spi_nor_sr2_bit7_quad_enable() - set QE bit in Status Register 2.
2116  * @nor:	pointer to a 'struct spi_nor'
2117  *
2118  * Set the Quad Enable (QE) bit in the Status Register 2.
2119  *
2120  * This is one of the procedures to set the QE bit described in the SFDP
2121  * (JESD216 rev B) specification but no manufacturer using this procedure has
2122  * been identified yet, hence the name of the function.
2123  *
2124  * Return: 0 on success, -errno otherwise.
2125  */
2126 int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor)
2127 {
2128 	u8 *sr2 = nor->bouncebuf;
2129 	int ret;
2130 	u8 sr2_written;
2131 
2132 	/* Check current Quad Enable bit value. */
2133 	ret = spi_nor_read_sr2(nor, sr2);
2134 	if (ret)
2135 		return ret;
2136 	if (*sr2 & SR2_QUAD_EN_BIT7)
2137 		return 0;
2138 
2139 	/* Update the Quad Enable bit. */
2140 	*sr2 |= SR2_QUAD_EN_BIT7;
2141 
2142 	ret = spi_nor_write_sr2(nor, sr2);
2143 	if (ret)
2144 		return ret;
2145 
2146 	sr2_written = *sr2;
2147 
2148 	/* Read back and check it. */
2149 	ret = spi_nor_read_sr2(nor, sr2);
2150 	if (ret)
2151 		return ret;
2152 
2153 	if (*sr2 != sr2_written) {
2154 		dev_dbg(nor->dev, "SR2: Read back test failed\n");
2155 		return -EIO;
2156 	}
2157 
2158 	return 0;
2159 }
2160 
2161 static const struct spi_nor_manufacturer *manufacturers[] = {
2162 	&spi_nor_atmel,
2163 	&spi_nor_catalyst,
2164 	&spi_nor_eon,
2165 	&spi_nor_esmt,
2166 	&spi_nor_everspin,
2167 	&spi_nor_fujitsu,
2168 	&spi_nor_gigadevice,
2169 	&spi_nor_intel,
2170 	&spi_nor_issi,
2171 	&spi_nor_macronix,
2172 	&spi_nor_micron,
2173 	&spi_nor_st,
2174 	&spi_nor_spansion,
2175 	&spi_nor_sst,
2176 	&spi_nor_winbond,
2177 	&spi_nor_xilinx,
2178 	&spi_nor_xmc,
2179 };
2180 
2181 static const struct flash_info *
2182 spi_nor_search_part_by_id(const struct flash_info *parts, unsigned int nparts,
2183 			  const u8 *id)
2184 {
2185 	unsigned int i;
2186 
2187 	for (i = 0; i < nparts; i++) {
2188 		if (parts[i].id_len &&
2189 		    !memcmp(parts[i].id, id, parts[i].id_len))
2190 			return &parts[i];
2191 	}
2192 
2193 	return NULL;
2194 }
2195 
2196 static const struct flash_info *spi_nor_read_id(struct spi_nor *nor)
2197 {
2198 	const struct flash_info *info;
2199 	u8 *id = nor->bouncebuf;
2200 	unsigned int i;
2201 	int ret;
2202 
2203 	if (nor->spimem) {
2204 		struct spi_mem_op op =
2205 			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_RDID, 1),
2206 				   SPI_MEM_OP_NO_ADDR,
2207 				   SPI_MEM_OP_NO_DUMMY,
2208 				   SPI_MEM_OP_DATA_IN(SPI_NOR_MAX_ID_LEN, id, 1));
2209 
2210 		ret = spi_mem_exec_op(nor->spimem, &op);
2211 	} else {
2212 		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDID, id,
2213 						    SPI_NOR_MAX_ID_LEN);
2214 	}
2215 	if (ret) {
2216 		dev_dbg(nor->dev, "error %d reading JEDEC ID\n", ret);
2217 		return ERR_PTR(ret);
2218 	}
2219 
2220 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
2221 		info = spi_nor_search_part_by_id(manufacturers[i]->parts,
2222 						 manufacturers[i]->nparts,
2223 						 id);
2224 		if (info) {
2225 			nor->manufacturer = manufacturers[i];
2226 			return info;
2227 		}
2228 	}
2229 
2230 	dev_err(nor->dev, "unrecognized JEDEC id bytes: %*ph\n",
2231 		SPI_NOR_MAX_ID_LEN, id);
2232 	return ERR_PTR(-ENODEV);
2233 }
2234 
2235 static int spi_nor_read(struct mtd_info *mtd, loff_t from, size_t len,
2236 			size_t *retlen, u_char *buf)
2237 {
2238 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2239 	ssize_t ret;
2240 
2241 	dev_dbg(nor->dev, "from 0x%08x, len %zd\n", (u32)from, len);
2242 
2243 	ret = spi_nor_lock_and_prep(nor);
2244 	if (ret)
2245 		return ret;
2246 
2247 	while (len) {
2248 		loff_t addr = from;
2249 
2250 		addr = spi_nor_convert_addr(nor, addr);
2251 
2252 		ret = spi_nor_read_data(nor, addr, len, buf);
2253 		if (ret == 0) {
2254 			/* We shouldn't see 0-length reads */
2255 			ret = -EIO;
2256 			goto read_err;
2257 		}
2258 		if (ret < 0)
2259 			goto read_err;
2260 
2261 		WARN_ON(ret > len);
2262 		*retlen += ret;
2263 		buf += ret;
2264 		from += ret;
2265 		len -= ret;
2266 	}
2267 	ret = 0;
2268 
2269 read_err:
2270 	spi_nor_unlock_and_unprep(nor);
2271 	return ret;
2272 }
2273 
2274 /*
2275  * Write an address range to the nor chip.  Data must be written in
2276  * FLASH_PAGESIZE chunks.  The address range may be any size provided
2277  * it is within the physical boundaries.
2278  */
2279 static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
2280 	size_t *retlen, const u_char *buf)
2281 {
2282 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
2283 	size_t page_offset, page_remain, i;
2284 	ssize_t ret;
2285 
2286 	dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len);
2287 
2288 	ret = spi_nor_lock_and_prep(nor);
2289 	if (ret)
2290 		return ret;
2291 
2292 	for (i = 0; i < len; ) {
2293 		ssize_t written;
2294 		loff_t addr = to + i;
2295 
2296 		/*
2297 		 * If page_size is a power of two, the offset can be quickly
2298 		 * calculated with an AND operation. On the other cases we
2299 		 * need to do a modulus operation (more expensive).
2300 		 * Power of two numbers have only one bit set and we can use
2301 		 * the instruction hweight32 to detect if we need to do a
2302 		 * modulus (do_div()) or not.
2303 		 */
2304 		if (hweight32(nor->page_size) == 1) {
2305 			page_offset = addr & (nor->page_size - 1);
2306 		} else {
2307 			uint64_t aux = addr;
2308 
2309 			page_offset = do_div(aux, nor->page_size);
2310 		}
2311 		/* the size of data remaining on the first page */
2312 		page_remain = min_t(size_t,
2313 				    nor->page_size - page_offset, len - i);
2314 
2315 		addr = spi_nor_convert_addr(nor, addr);
2316 
2317 		ret = spi_nor_write_enable(nor);
2318 		if (ret)
2319 			goto write_err;
2320 
2321 		ret = spi_nor_write_data(nor, addr, page_remain, buf + i);
2322 		if (ret < 0)
2323 			goto write_err;
2324 		written = ret;
2325 
2326 		ret = spi_nor_wait_till_ready(nor);
2327 		if (ret)
2328 			goto write_err;
2329 		*retlen += written;
2330 		i += written;
2331 	}
2332 
2333 write_err:
2334 	spi_nor_unlock_and_unprep(nor);
2335 	return ret;
2336 }
2337 
2338 static int spi_nor_check(struct spi_nor *nor)
2339 {
2340 	if (!nor->dev ||
2341 	    (!nor->spimem && !nor->controller_ops) ||
2342 	    (!nor->spimem && nor->controller_ops &&
2343 	    (!nor->controller_ops->read ||
2344 	     !nor->controller_ops->write ||
2345 	     !nor->controller_ops->read_reg ||
2346 	     !nor->controller_ops->write_reg))) {
2347 		pr_err("spi-nor: please fill all the necessary fields!\n");
2348 		return -EINVAL;
2349 	}
2350 
2351 	if (nor->spimem && nor->controller_ops) {
2352 		dev_err(nor->dev, "nor->spimem and nor->controller_ops are mutually exclusive, please set just one of them.\n");
2353 		return -EINVAL;
2354 	}
2355 
2356 	return 0;
2357 }
2358 
2359 void
2360 spi_nor_set_read_settings(struct spi_nor_read_command *read,
2361 			  u8 num_mode_clocks,
2362 			  u8 num_wait_states,
2363 			  u8 opcode,
2364 			  enum spi_nor_protocol proto)
2365 {
2366 	read->num_mode_clocks = num_mode_clocks;
2367 	read->num_wait_states = num_wait_states;
2368 	read->opcode = opcode;
2369 	read->proto = proto;
2370 }
2371 
2372 void spi_nor_set_pp_settings(struct spi_nor_pp_command *pp, u8 opcode,
2373 			     enum spi_nor_protocol proto)
2374 {
2375 	pp->opcode = opcode;
2376 	pp->proto = proto;
2377 }
2378 
2379 static int spi_nor_hwcaps2cmd(u32 hwcaps, const int table[][2], size_t size)
2380 {
2381 	size_t i;
2382 
2383 	for (i = 0; i < size; i++)
2384 		if (table[i][0] == (int)hwcaps)
2385 			return table[i][1];
2386 
2387 	return -EINVAL;
2388 }
2389 
2390 int spi_nor_hwcaps_read2cmd(u32 hwcaps)
2391 {
2392 	static const int hwcaps_read2cmd[][2] = {
2393 		{ SNOR_HWCAPS_READ,		SNOR_CMD_READ },
2394 		{ SNOR_HWCAPS_READ_FAST,	SNOR_CMD_READ_FAST },
2395 		{ SNOR_HWCAPS_READ_1_1_1_DTR,	SNOR_CMD_READ_1_1_1_DTR },
2396 		{ SNOR_HWCAPS_READ_1_1_2,	SNOR_CMD_READ_1_1_2 },
2397 		{ SNOR_HWCAPS_READ_1_2_2,	SNOR_CMD_READ_1_2_2 },
2398 		{ SNOR_HWCAPS_READ_2_2_2,	SNOR_CMD_READ_2_2_2 },
2399 		{ SNOR_HWCAPS_READ_1_2_2_DTR,	SNOR_CMD_READ_1_2_2_DTR },
2400 		{ SNOR_HWCAPS_READ_1_1_4,	SNOR_CMD_READ_1_1_4 },
2401 		{ SNOR_HWCAPS_READ_1_4_4,	SNOR_CMD_READ_1_4_4 },
2402 		{ SNOR_HWCAPS_READ_4_4_4,	SNOR_CMD_READ_4_4_4 },
2403 		{ SNOR_HWCAPS_READ_1_4_4_DTR,	SNOR_CMD_READ_1_4_4_DTR },
2404 		{ SNOR_HWCAPS_READ_1_1_8,	SNOR_CMD_READ_1_1_8 },
2405 		{ SNOR_HWCAPS_READ_1_8_8,	SNOR_CMD_READ_1_8_8 },
2406 		{ SNOR_HWCAPS_READ_8_8_8,	SNOR_CMD_READ_8_8_8 },
2407 		{ SNOR_HWCAPS_READ_1_8_8_DTR,	SNOR_CMD_READ_1_8_8_DTR },
2408 		{ SNOR_HWCAPS_READ_8_8_8_DTR,	SNOR_CMD_READ_8_8_8_DTR },
2409 	};
2410 
2411 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_read2cmd,
2412 				  ARRAY_SIZE(hwcaps_read2cmd));
2413 }
2414 
2415 static int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
2416 {
2417 	static const int hwcaps_pp2cmd[][2] = {
2418 		{ SNOR_HWCAPS_PP,		SNOR_CMD_PP },
2419 		{ SNOR_HWCAPS_PP_1_1_4,		SNOR_CMD_PP_1_1_4 },
2420 		{ SNOR_HWCAPS_PP_1_4_4,		SNOR_CMD_PP_1_4_4 },
2421 		{ SNOR_HWCAPS_PP_4_4_4,		SNOR_CMD_PP_4_4_4 },
2422 		{ SNOR_HWCAPS_PP_1_1_8,		SNOR_CMD_PP_1_1_8 },
2423 		{ SNOR_HWCAPS_PP_1_8_8,		SNOR_CMD_PP_1_8_8 },
2424 		{ SNOR_HWCAPS_PP_8_8_8,		SNOR_CMD_PP_8_8_8 },
2425 		{ SNOR_HWCAPS_PP_8_8_8_DTR,	SNOR_CMD_PP_8_8_8_DTR },
2426 	};
2427 
2428 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_pp2cmd,
2429 				  ARRAY_SIZE(hwcaps_pp2cmd));
2430 }
2431 
2432 /**
2433  * spi_nor_spimem_check_op - check if the operation is supported
2434  *                           by controller
2435  *@nor:        pointer to a 'struct spi_nor'
2436  *@op:         pointer to op template to be checked
2437  *
2438  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2439  */
2440 static int spi_nor_spimem_check_op(struct spi_nor *nor,
2441 				   struct spi_mem_op *op)
2442 {
2443 	/*
2444 	 * First test with 4 address bytes. The opcode itself might
2445 	 * be a 3B addressing opcode but we don't care, because
2446 	 * SPI controller implementation should not check the opcode,
2447 	 * but just the sequence.
2448 	 */
2449 	op->addr.nbytes = 4;
2450 	if (!spi_mem_supports_op(nor->spimem, op)) {
2451 		if (nor->mtd.size > SZ_16M)
2452 			return -EOPNOTSUPP;
2453 
2454 		/* If flash size <= 16MB, 3 address bytes are sufficient */
2455 		op->addr.nbytes = 3;
2456 		if (!spi_mem_supports_op(nor->spimem, op))
2457 			return -EOPNOTSUPP;
2458 	}
2459 
2460 	return 0;
2461 }
2462 
2463 /**
2464  * spi_nor_spimem_check_readop - check if the read op is supported
2465  *                               by controller
2466  *@nor:         pointer to a 'struct spi_nor'
2467  *@read:        pointer to op template to be checked
2468  *
2469  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2470  */
2471 static int spi_nor_spimem_check_readop(struct spi_nor *nor,
2472 				       const struct spi_nor_read_command *read)
2473 {
2474 	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(read->opcode, 0),
2475 					  SPI_MEM_OP_ADDR(3, 0, 0),
2476 					  SPI_MEM_OP_DUMMY(1, 0),
2477 					  SPI_MEM_OP_DATA_IN(1, NULL, 0));
2478 
2479 	spi_nor_spimem_setup_op(nor, &op, read->proto);
2480 
2481 	/* convert the dummy cycles to the number of bytes */
2482 	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
2483 	if (spi_nor_protocol_is_dtr(nor->read_proto))
2484 		op.dummy.nbytes *= 2;
2485 
2486 	return spi_nor_spimem_check_op(nor, &op);
2487 }
2488 
2489 /**
2490  * spi_nor_spimem_check_pp - check if the page program op is supported
2491  *                           by controller
2492  *@nor:         pointer to a 'struct spi_nor'
2493  *@pp:          pointer to op template to be checked
2494  *
2495  * Returns 0 if operation is supported, -EOPNOTSUPP otherwise.
2496  */
2497 static int spi_nor_spimem_check_pp(struct spi_nor *nor,
2498 				   const struct spi_nor_pp_command *pp)
2499 {
2500 	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(pp->opcode, 0),
2501 					  SPI_MEM_OP_ADDR(3, 0, 0),
2502 					  SPI_MEM_OP_NO_DUMMY,
2503 					  SPI_MEM_OP_DATA_OUT(1, NULL, 0));
2504 
2505 	spi_nor_spimem_setup_op(nor, &op, pp->proto);
2506 
2507 	return spi_nor_spimem_check_op(nor, &op);
2508 }
2509 
2510 /**
2511  * spi_nor_spimem_adjust_hwcaps - Find optimal Read/Write protocol
2512  *                                based on SPI controller capabilities
2513  * @nor:        pointer to a 'struct spi_nor'
2514  * @hwcaps:     pointer to resulting capabilities after adjusting
2515  *              according to controller and flash's capability
2516  */
2517 static void
2518 spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor, u32 *hwcaps)
2519 {
2520 	struct spi_nor_flash_parameter *params = nor->params;
2521 	unsigned int cap;
2522 
2523 	/* X-X-X modes are not supported yet, mask them all. */
2524 	*hwcaps &= ~SNOR_HWCAPS_X_X_X;
2525 
2526 	/*
2527 	 * If the reset line is broken, we do not want to enter a stateful
2528 	 * mode.
2529 	 */
2530 	if (nor->flags & SNOR_F_BROKEN_RESET)
2531 		*hwcaps &= ~(SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR);
2532 
2533 	for (cap = 0; cap < sizeof(*hwcaps) * BITS_PER_BYTE; cap++) {
2534 		int rdidx, ppidx;
2535 
2536 		if (!(*hwcaps & BIT(cap)))
2537 			continue;
2538 
2539 		rdidx = spi_nor_hwcaps_read2cmd(BIT(cap));
2540 		if (rdidx >= 0 &&
2541 		    spi_nor_spimem_check_readop(nor, &params->reads[rdidx]))
2542 			*hwcaps &= ~BIT(cap);
2543 
2544 		ppidx = spi_nor_hwcaps_pp2cmd(BIT(cap));
2545 		if (ppidx < 0)
2546 			continue;
2547 
2548 		if (spi_nor_spimem_check_pp(nor,
2549 					    &params->page_programs[ppidx]))
2550 			*hwcaps &= ~BIT(cap);
2551 	}
2552 }
2553 
2554 /**
2555  * spi_nor_set_erase_type() - set a SPI NOR erase type
2556  * @erase:	pointer to a structure that describes a SPI NOR erase type
2557  * @size:	the size of the sector/block erased by the erase type
2558  * @opcode:	the SPI command op code to erase the sector/block
2559  */
2560 void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
2561 			    u8 opcode)
2562 {
2563 	erase->size = size;
2564 	erase->opcode = opcode;
2565 	/* JEDEC JESD216B Standard imposes erase sizes to be power of 2. */
2566 	erase->size_shift = ffs(erase->size) - 1;
2567 	erase->size_mask = (1 << erase->size_shift) - 1;
2568 }
2569 
2570 /**
2571  * spi_nor_init_uniform_erase_map() - Initialize uniform erase map
2572  * @map:		the erase map of the SPI NOR
2573  * @erase_mask:		bitmask encoding erase types that can erase the entire
2574  *			flash memory
2575  * @flash_size:		the spi nor flash memory size
2576  */
2577 void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
2578 				    u8 erase_mask, u64 flash_size)
2579 {
2580 	/* Offset 0 with erase_mask and SNOR_LAST_REGION bit set */
2581 	map->uniform_region.offset = (erase_mask & SNOR_ERASE_TYPE_MASK) |
2582 				     SNOR_LAST_REGION;
2583 	map->uniform_region.size = flash_size;
2584 	map->regions = &map->uniform_region;
2585 	map->uniform_erase_type = erase_mask;
2586 }
2587 
2588 int spi_nor_post_bfpt_fixups(struct spi_nor *nor,
2589 			     const struct sfdp_parameter_header *bfpt_header,
2590 			     const struct sfdp_bfpt *bfpt,
2591 			     struct spi_nor_flash_parameter *params)
2592 {
2593 	int ret;
2594 
2595 	if (nor->manufacturer && nor->manufacturer->fixups &&
2596 	    nor->manufacturer->fixups->post_bfpt) {
2597 		ret = nor->manufacturer->fixups->post_bfpt(nor, bfpt_header,
2598 							   bfpt, params);
2599 		if (ret)
2600 			return ret;
2601 	}
2602 
2603 	if (nor->info->fixups && nor->info->fixups->post_bfpt)
2604 		return nor->info->fixups->post_bfpt(nor, bfpt_header, bfpt,
2605 						    params);
2606 
2607 	return 0;
2608 }
2609 
2610 static int spi_nor_select_read(struct spi_nor *nor,
2611 			       u32 shared_hwcaps)
2612 {
2613 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_READ_MASK) - 1;
2614 	const struct spi_nor_read_command *read;
2615 
2616 	if (best_match < 0)
2617 		return -EINVAL;
2618 
2619 	cmd = spi_nor_hwcaps_read2cmd(BIT(best_match));
2620 	if (cmd < 0)
2621 		return -EINVAL;
2622 
2623 	read = &nor->params->reads[cmd];
2624 	nor->read_opcode = read->opcode;
2625 	nor->read_proto = read->proto;
2626 
2627 	/*
2628 	 * In the SPI NOR framework, we don't need to make the difference
2629 	 * between mode clock cycles and wait state clock cycles.
2630 	 * Indeed, the value of the mode clock cycles is used by a QSPI
2631 	 * flash memory to know whether it should enter or leave its 0-4-4
2632 	 * (Continuous Read / XIP) mode.
2633 	 * eXecution In Place is out of the scope of the mtd sub-system.
2634 	 * Hence we choose to merge both mode and wait state clock cycles
2635 	 * into the so called dummy clock cycles.
2636 	 */
2637 	nor->read_dummy = read->num_mode_clocks + read->num_wait_states;
2638 	return 0;
2639 }
2640 
2641 static int spi_nor_select_pp(struct spi_nor *nor,
2642 			     u32 shared_hwcaps)
2643 {
2644 	int cmd, best_match = fls(shared_hwcaps & SNOR_HWCAPS_PP_MASK) - 1;
2645 	const struct spi_nor_pp_command *pp;
2646 
2647 	if (best_match < 0)
2648 		return -EINVAL;
2649 
2650 	cmd = spi_nor_hwcaps_pp2cmd(BIT(best_match));
2651 	if (cmd < 0)
2652 		return -EINVAL;
2653 
2654 	pp = &nor->params->page_programs[cmd];
2655 	nor->program_opcode = pp->opcode;
2656 	nor->write_proto = pp->proto;
2657 	return 0;
2658 }
2659 
2660 /**
2661  * spi_nor_select_uniform_erase() - select optimum uniform erase type
2662  * @map:		the erase map of the SPI NOR
2663  * @wanted_size:	the erase type size to search for. Contains the value of
2664  *			info->sector_size or of the "small sector" size in case
2665  *			CONFIG_MTD_SPI_NOR_USE_4K_SECTORS is defined.
2666  *
2667  * Once the optimum uniform sector erase command is found, disable all the
2668  * other.
2669  *
2670  * Return: pointer to erase type on success, NULL otherwise.
2671  */
2672 static const struct spi_nor_erase_type *
2673 spi_nor_select_uniform_erase(struct spi_nor_erase_map *map,
2674 			     const u32 wanted_size)
2675 {
2676 	const struct spi_nor_erase_type *tested_erase, *erase = NULL;
2677 	int i;
2678 	u8 uniform_erase_type = map->uniform_erase_type;
2679 
2680 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2681 		if (!(uniform_erase_type & BIT(i)))
2682 			continue;
2683 
2684 		tested_erase = &map->erase_type[i];
2685 
2686 		/*
2687 		 * If the current erase size is the one, stop here:
2688 		 * we have found the right uniform Sector Erase command.
2689 		 */
2690 		if (tested_erase->size == wanted_size) {
2691 			erase = tested_erase;
2692 			break;
2693 		}
2694 
2695 		/*
2696 		 * Otherwise, the current erase size is still a valid candidate.
2697 		 * Select the biggest valid candidate.
2698 		 */
2699 		if (!erase && tested_erase->size)
2700 			erase = tested_erase;
2701 			/* keep iterating to find the wanted_size */
2702 	}
2703 
2704 	if (!erase)
2705 		return NULL;
2706 
2707 	/* Disable all other Sector Erase commands. */
2708 	map->uniform_erase_type &= ~SNOR_ERASE_TYPE_MASK;
2709 	map->uniform_erase_type |= BIT(erase - map->erase_type);
2710 	return erase;
2711 }
2712 
2713 static int spi_nor_select_erase(struct spi_nor *nor)
2714 {
2715 	struct spi_nor_erase_map *map = &nor->params->erase_map;
2716 	const struct spi_nor_erase_type *erase = NULL;
2717 	struct mtd_info *mtd = &nor->mtd;
2718 	u32 wanted_size = nor->info->sector_size;
2719 	int i;
2720 
2721 	/*
2722 	 * The previous implementation handling Sector Erase commands assumed
2723 	 * that the SPI flash memory has an uniform layout then used only one
2724 	 * of the supported erase sizes for all Sector Erase commands.
2725 	 * So to be backward compatible, the new implementation also tries to
2726 	 * manage the SPI flash memory as uniform with a single erase sector
2727 	 * size, when possible.
2728 	 */
2729 #ifdef CONFIG_MTD_SPI_NOR_USE_4K_SECTORS
2730 	/* prefer "small sector" erase if possible */
2731 	wanted_size = 4096u;
2732 #endif
2733 
2734 	if (spi_nor_has_uniform_erase(nor)) {
2735 		erase = spi_nor_select_uniform_erase(map, wanted_size);
2736 		if (!erase)
2737 			return -EINVAL;
2738 		nor->erase_opcode = erase->opcode;
2739 		mtd->erasesize = erase->size;
2740 		return 0;
2741 	}
2742 
2743 	/*
2744 	 * For non-uniform SPI flash memory, set mtd->erasesize to the
2745 	 * maximum erase sector size. No need to set nor->erase_opcode.
2746 	 */
2747 	for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
2748 		if (map->erase_type[i].size) {
2749 			erase = &map->erase_type[i];
2750 			break;
2751 		}
2752 	}
2753 
2754 	if (!erase)
2755 		return -EINVAL;
2756 
2757 	mtd->erasesize = erase->size;
2758 	return 0;
2759 }
2760 
2761 static int spi_nor_default_setup(struct spi_nor *nor,
2762 				 const struct spi_nor_hwcaps *hwcaps)
2763 {
2764 	struct spi_nor_flash_parameter *params = nor->params;
2765 	u32 ignored_mask, shared_mask;
2766 	int err;
2767 
2768 	/*
2769 	 * Keep only the hardware capabilities supported by both the SPI
2770 	 * controller and the SPI flash memory.
2771 	 */
2772 	shared_mask = hwcaps->mask & params->hwcaps.mask;
2773 
2774 	if (nor->spimem) {
2775 		/*
2776 		 * When called from spi_nor_probe(), all caps are set and we
2777 		 * need to discard some of them based on what the SPI
2778 		 * controller actually supports (using spi_mem_supports_op()).
2779 		 */
2780 		spi_nor_spimem_adjust_hwcaps(nor, &shared_mask);
2781 	} else {
2782 		/*
2783 		 * SPI n-n-n protocols are not supported when the SPI
2784 		 * controller directly implements the spi_nor interface.
2785 		 * Yet another reason to switch to spi-mem.
2786 		 */
2787 		ignored_mask = SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR;
2788 		if (shared_mask & ignored_mask) {
2789 			dev_dbg(nor->dev,
2790 				"SPI n-n-n protocols are not supported.\n");
2791 			shared_mask &= ~ignored_mask;
2792 		}
2793 	}
2794 
2795 	/* Select the (Fast) Read command. */
2796 	err = spi_nor_select_read(nor, shared_mask);
2797 	if (err) {
2798 		dev_dbg(nor->dev,
2799 			"can't select read settings supported by both the SPI controller and memory.\n");
2800 		return err;
2801 	}
2802 
2803 	/* Select the Page Program command. */
2804 	err = spi_nor_select_pp(nor, shared_mask);
2805 	if (err) {
2806 		dev_dbg(nor->dev,
2807 			"can't select write settings supported by both the SPI controller and memory.\n");
2808 		return err;
2809 	}
2810 
2811 	/* Select the Sector Erase command. */
2812 	err = spi_nor_select_erase(nor);
2813 	if (err) {
2814 		dev_dbg(nor->dev,
2815 			"can't select erase settings supported by both the SPI controller and memory.\n");
2816 		return err;
2817 	}
2818 
2819 	return 0;
2820 }
2821 
2822 static int spi_nor_setup(struct spi_nor *nor,
2823 			 const struct spi_nor_hwcaps *hwcaps)
2824 {
2825 	if (!nor->params->setup)
2826 		return 0;
2827 
2828 	return nor->params->setup(nor, hwcaps);
2829 }
2830 
2831 /**
2832  * spi_nor_manufacturer_init_params() - Initialize the flash's parameters and
2833  * settings based on MFR register and ->default_init() hook.
2834  * @nor:	pointer to a 'struct spi_nor'.
2835  */
2836 static void spi_nor_manufacturer_init_params(struct spi_nor *nor)
2837 {
2838 	if (nor->manufacturer && nor->manufacturer->fixups &&
2839 	    nor->manufacturer->fixups->default_init)
2840 		nor->manufacturer->fixups->default_init(nor);
2841 
2842 	if (nor->info->fixups && nor->info->fixups->default_init)
2843 		nor->info->fixups->default_init(nor);
2844 }
2845 
2846 /**
2847  * spi_nor_sfdp_init_params() - Initialize the flash's parameters and settings
2848  * based on JESD216 SFDP standard.
2849  * @nor:	pointer to a 'struct spi_nor'.
2850  *
2851  * The method has a roll-back mechanism: in case the SFDP parsing fails, the
2852  * legacy flash parameters and settings will be restored.
2853  */
2854 static void spi_nor_sfdp_init_params(struct spi_nor *nor)
2855 {
2856 	struct spi_nor_flash_parameter sfdp_params;
2857 
2858 	memcpy(&sfdp_params, nor->params, sizeof(sfdp_params));
2859 
2860 	if (spi_nor_parse_sfdp(nor, nor->params)) {
2861 		memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
2862 		nor->addr_width = 0;
2863 		nor->flags &= ~SNOR_F_4B_OPCODES;
2864 	}
2865 }
2866 
2867 /**
2868  * spi_nor_info_init_params() - Initialize the flash's parameters and settings
2869  * based on nor->info data.
2870  * @nor:	pointer to a 'struct spi_nor'.
2871  */
2872 static void spi_nor_info_init_params(struct spi_nor *nor)
2873 {
2874 	struct spi_nor_flash_parameter *params = nor->params;
2875 	struct spi_nor_erase_map *map = &params->erase_map;
2876 	const struct flash_info *info = nor->info;
2877 	struct device_node *np = spi_nor_get_flash_node(nor);
2878 	u8 i, erase_mask;
2879 
2880 	/* Initialize legacy flash parameters and settings. */
2881 	params->quad_enable = spi_nor_sr2_bit1_quad_enable;
2882 	params->set_4byte_addr_mode = spansion_set_4byte_addr_mode;
2883 	params->setup = spi_nor_default_setup;
2884 	/* Default to 16-bit Write Status (01h) Command */
2885 	nor->flags |= SNOR_F_HAS_16BIT_SR;
2886 
2887 	/* Set SPI NOR sizes. */
2888 	params->writesize = 1;
2889 	params->size = (u64)info->sector_size * info->n_sectors;
2890 	params->page_size = info->page_size;
2891 
2892 	if (!(info->flags & SPI_NOR_NO_FR)) {
2893 		/* Default to Fast Read for DT and non-DT platform devices. */
2894 		params->hwcaps.mask |= SNOR_HWCAPS_READ_FAST;
2895 
2896 		/* Mask out Fast Read if not requested at DT instantiation. */
2897 		if (np && !of_property_read_bool(np, "m25p,fast-read"))
2898 			params->hwcaps.mask &= ~SNOR_HWCAPS_READ_FAST;
2899 	}
2900 
2901 	/* (Fast) Read settings. */
2902 	params->hwcaps.mask |= SNOR_HWCAPS_READ;
2903 	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ],
2904 				  0, 0, SPINOR_OP_READ,
2905 				  SNOR_PROTO_1_1_1);
2906 
2907 	if (params->hwcaps.mask & SNOR_HWCAPS_READ_FAST)
2908 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_FAST],
2909 					  0, 8, SPINOR_OP_READ_FAST,
2910 					  SNOR_PROTO_1_1_1);
2911 
2912 	if (info->flags & SPI_NOR_DUAL_READ) {
2913 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
2914 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_2],
2915 					  0, 8, SPINOR_OP_READ_1_1_2,
2916 					  SNOR_PROTO_1_1_2);
2917 	}
2918 
2919 	if (info->flags & SPI_NOR_QUAD_READ) {
2920 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
2921 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_4],
2922 					  0, 8, SPINOR_OP_READ_1_1_4,
2923 					  SNOR_PROTO_1_1_4);
2924 	}
2925 
2926 	if (info->flags & SPI_NOR_OCTAL_READ) {
2927 		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
2928 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
2929 					  0, 8, SPINOR_OP_READ_1_1_8,
2930 					  SNOR_PROTO_1_1_8);
2931 	}
2932 
2933 	if (info->flags & SPI_NOR_OCTAL_DTR_READ) {
2934 		params->hwcaps.mask |= SNOR_HWCAPS_READ_8_8_8_DTR;
2935 		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_8_8_8_DTR],
2936 					  0, 20, SPINOR_OP_READ_FAST,
2937 					  SNOR_PROTO_8_8_8_DTR);
2938 	}
2939 
2940 	/* Page Program settings. */
2941 	params->hwcaps.mask |= SNOR_HWCAPS_PP;
2942 	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP],
2943 				SPINOR_OP_PP, SNOR_PROTO_1_1_1);
2944 
2945 	if (info->flags & SPI_NOR_OCTAL_DTR_PP) {
2946 		params->hwcaps.mask |= SNOR_HWCAPS_PP_8_8_8_DTR;
2947 		/*
2948 		 * Since xSPI Page Program opcode is backward compatible with
2949 		 * Legacy SPI, use Legacy SPI opcode there as well.
2950 		 */
2951 		spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_8_8_8_DTR],
2952 					SPINOR_OP_PP, SNOR_PROTO_8_8_8_DTR);
2953 	}
2954 
2955 	/*
2956 	 * Sector Erase settings. Sort Erase Types in ascending order, with the
2957 	 * smallest erase size starting at BIT(0).
2958 	 */
2959 	erase_mask = 0;
2960 	i = 0;
2961 	if (info->flags & SECT_4K_PMC) {
2962 		erase_mask |= BIT(i);
2963 		spi_nor_set_erase_type(&map->erase_type[i], 4096u,
2964 				       SPINOR_OP_BE_4K_PMC);
2965 		i++;
2966 	} else if (info->flags & SECT_4K) {
2967 		erase_mask |= BIT(i);
2968 		spi_nor_set_erase_type(&map->erase_type[i], 4096u,
2969 				       SPINOR_OP_BE_4K);
2970 		i++;
2971 	}
2972 	erase_mask |= BIT(i);
2973 	spi_nor_set_erase_type(&map->erase_type[i], info->sector_size,
2974 			       SPINOR_OP_SE);
2975 	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
2976 }
2977 
2978 /**
2979  * spi_nor_post_sfdp_fixups() - Updates the flash's parameters and settings
2980  * after SFDP has been parsed (is also called for SPI NORs that do not
2981  * support RDSFDP).
2982  * @nor:	pointer to a 'struct spi_nor'
2983  *
2984  * Typically used to tweak various parameters that could not be extracted by
2985  * other means (i.e. when information provided by the SFDP/flash_info tables
2986  * are incomplete or wrong).
2987  */
2988 static void spi_nor_post_sfdp_fixups(struct spi_nor *nor)
2989 {
2990 	if (nor->manufacturer && nor->manufacturer->fixups &&
2991 	    nor->manufacturer->fixups->post_sfdp)
2992 		nor->manufacturer->fixups->post_sfdp(nor);
2993 
2994 	if (nor->info->fixups && nor->info->fixups->post_sfdp)
2995 		nor->info->fixups->post_sfdp(nor);
2996 }
2997 
2998 /**
2999  * spi_nor_late_init_params() - Late initialization of default flash parameters.
3000  * @nor:	pointer to a 'struct spi_nor'
3001  *
3002  * Used to set default flash parameters and settings when the ->default_init()
3003  * hook or the SFDP parser let voids.
3004  */
3005 static void spi_nor_late_init_params(struct spi_nor *nor)
3006 {
3007 	/*
3008 	 * NOR protection support. When locking_ops are not provided, we pick
3009 	 * the default ones.
3010 	 */
3011 	if (nor->flags & SNOR_F_HAS_LOCK && !nor->params->locking_ops)
3012 		nor->params->locking_ops = &spi_nor_sr_locking_ops;
3013 }
3014 
3015 /**
3016  * spi_nor_init_params() - Initialize the flash's parameters and settings.
3017  * @nor:	pointer to a 'struct spi_nor'.
3018  *
3019  * The flash parameters and settings are initialized based on a sequence of
3020  * calls that are ordered by priority:
3021  *
3022  * 1/ Default flash parameters initialization. The initializations are done
3023  *    based on nor->info data:
3024  *		spi_nor_info_init_params()
3025  *
3026  * which can be overwritten by:
3027  * 2/ Manufacturer flash parameters initialization. The initializations are
3028  *    done based on MFR register, or when the decisions can not be done solely
3029  *    based on MFR, by using specific flash_info tweeks, ->default_init():
3030  *		spi_nor_manufacturer_init_params()
3031  *
3032  * which can be overwritten by:
3033  * 3/ SFDP flash parameters initialization. JESD216 SFDP is a standard and
3034  *    should be more accurate that the above.
3035  *		spi_nor_sfdp_init_params()
3036  *
3037  *    Please note that there is a ->post_bfpt() fixup hook that can overwrite
3038  *    the flash parameters and settings immediately after parsing the Basic
3039  *    Flash Parameter Table.
3040  *
3041  * which can be overwritten by:
3042  * 4/ Post SFDP flash parameters initialization. Used to tweak various
3043  *    parameters that could not be extracted by other means (i.e. when
3044  *    information provided by the SFDP/flash_info tables are incomplete or
3045  *    wrong).
3046  *		spi_nor_post_sfdp_fixups()
3047  *
3048  * 5/ Late default flash parameters initialization, used when the
3049  * ->default_init() hook or the SFDP parser do not set specific params.
3050  *		spi_nor_late_init_params()
3051  */
3052 static int spi_nor_init_params(struct spi_nor *nor)
3053 {
3054 	nor->params = devm_kzalloc(nor->dev, sizeof(*nor->params), GFP_KERNEL);
3055 	if (!nor->params)
3056 		return -ENOMEM;
3057 
3058 	spi_nor_info_init_params(nor);
3059 
3060 	spi_nor_manufacturer_init_params(nor);
3061 
3062 	if ((nor->info->flags & (SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ |
3063 				 SPI_NOR_OCTAL_READ | SPI_NOR_OCTAL_DTR_READ)) &&
3064 	    !(nor->info->flags & SPI_NOR_SKIP_SFDP))
3065 		spi_nor_sfdp_init_params(nor);
3066 
3067 	spi_nor_post_sfdp_fixups(nor);
3068 
3069 	spi_nor_late_init_params(nor);
3070 
3071 	return 0;
3072 }
3073 
3074 /** spi_nor_octal_dtr_enable() - enable Octal DTR I/O if needed
3075  * @nor:                 pointer to a 'struct spi_nor'
3076  * @enable:              whether to enable or disable Octal DTR
3077  *
3078  * Return: 0 on success, -errno otherwise.
3079  */
3080 static int spi_nor_octal_dtr_enable(struct spi_nor *nor, bool enable)
3081 {
3082 	int ret;
3083 
3084 	if (!nor->params->octal_dtr_enable)
3085 		return 0;
3086 
3087 	if (!(nor->read_proto == SNOR_PROTO_8_8_8_DTR &&
3088 	      nor->write_proto == SNOR_PROTO_8_8_8_DTR))
3089 		return 0;
3090 
3091 	if (!(nor->flags & SNOR_F_IO_MODE_EN_VOLATILE))
3092 		return 0;
3093 
3094 	ret = nor->params->octal_dtr_enable(nor, enable);
3095 	if (ret)
3096 		return ret;
3097 
3098 	if (enable)
3099 		nor->reg_proto = SNOR_PROTO_8_8_8_DTR;
3100 	else
3101 		nor->reg_proto = SNOR_PROTO_1_1_1;
3102 
3103 	return 0;
3104 }
3105 
3106 /**
3107  * spi_nor_quad_enable() - enable Quad I/O if needed.
3108  * @nor:                pointer to a 'struct spi_nor'
3109  *
3110  * Return: 0 on success, -errno otherwise.
3111  */
3112 static int spi_nor_quad_enable(struct spi_nor *nor)
3113 {
3114 	if (!nor->params->quad_enable)
3115 		return 0;
3116 
3117 	if (!(spi_nor_get_protocol_width(nor->read_proto) == 4 ||
3118 	      spi_nor_get_protocol_width(nor->write_proto) == 4))
3119 		return 0;
3120 
3121 	return nor->params->quad_enable(nor);
3122 }
3123 
3124 /**
3125  * spi_nor_try_unlock_all() - Tries to unlock the entire flash memory array.
3126  * @nor:	pointer to a 'struct spi_nor'.
3127  *
3128  * Some SPI NOR flashes are write protected by default after a power-on reset
3129  * cycle, in order to avoid inadvertent writes during power-up. Backward
3130  * compatibility imposes to unlock the entire flash memory array at power-up
3131  * by default.
3132  *
3133  * Unprotecting the entire flash array will fail for boards which are hardware
3134  * write-protected. Thus any errors are ignored.
3135  */
3136 static void spi_nor_try_unlock_all(struct spi_nor *nor)
3137 {
3138 	int ret;
3139 
3140 	if (!(nor->flags & SNOR_F_HAS_LOCK))
3141 		return;
3142 
3143 	dev_dbg(nor->dev, "Unprotecting entire flash array\n");
3144 
3145 	ret = spi_nor_unlock(&nor->mtd, 0, nor->params->size);
3146 	if (ret)
3147 		dev_dbg(nor->dev, "Failed to unlock the entire flash memory array\n");
3148 }
3149 
3150 static int spi_nor_init(struct spi_nor *nor)
3151 {
3152 	int err;
3153 
3154 	err = spi_nor_octal_dtr_enable(nor, true);
3155 	if (err) {
3156 		dev_dbg(nor->dev, "octal mode not supported\n");
3157 		return err;
3158 	}
3159 
3160 	err = spi_nor_quad_enable(nor);
3161 	if (err) {
3162 		dev_dbg(nor->dev, "quad mode not supported\n");
3163 		return err;
3164 	}
3165 
3166 	/*
3167 	 * Some SPI NOR flashes are write protected by default after a power-on
3168 	 * reset cycle, in order to avoid inadvertent writes during power-up.
3169 	 * Backward compatibility imposes to unlock the entire flash memory
3170 	 * array at power-up by default. Depending on the kernel configuration
3171 	 * (1) do nothing, (2) always unlock the entire flash array or (3)
3172 	 * unlock the entire flash array only when the software write
3173 	 * protection bits are volatile. The latter is indicated by
3174 	 * SNOR_F_SWP_IS_VOLATILE.
3175 	 */
3176 	if (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE) ||
3177 	    (IS_ENABLED(CONFIG_MTD_SPI_NOR_SWP_DISABLE_ON_VOLATILE) &&
3178 	     nor->flags & SNOR_F_SWP_IS_VOLATILE))
3179 		spi_nor_try_unlock_all(nor);
3180 
3181 	if (nor->addr_width == 4 &&
3182 	    nor->read_proto != SNOR_PROTO_8_8_8_DTR &&
3183 	    !(nor->flags & SNOR_F_4B_OPCODES)) {
3184 		/*
3185 		 * If the RESET# pin isn't hooked up properly, or the system
3186 		 * otherwise doesn't perform a reset command in the boot
3187 		 * sequence, it's impossible to 100% protect against unexpected
3188 		 * reboots (e.g., crashes). Warn the user (or hopefully, system
3189 		 * designer) that this is bad.
3190 		 */
3191 		WARN_ONCE(nor->flags & SNOR_F_BROKEN_RESET,
3192 			  "enabling reset hack; may not recover from unexpected reboots\n");
3193 		nor->params->set_4byte_addr_mode(nor, true);
3194 	}
3195 
3196 	return 0;
3197 }
3198 
3199 static void spi_nor_soft_reset(struct spi_nor *nor)
3200 {
3201 	struct spi_mem_op op;
3202 	int ret;
3203 
3204 	op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_SRSTEN, 0),
3205 			SPI_MEM_OP_NO_DUMMY,
3206 			SPI_MEM_OP_NO_ADDR,
3207 			SPI_MEM_OP_NO_DATA);
3208 
3209 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3210 
3211 	ret = spi_mem_exec_op(nor->spimem, &op);
3212 	if (ret) {
3213 		dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3214 		return;
3215 	}
3216 
3217 	op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_SRST, 0),
3218 			SPI_MEM_OP_NO_DUMMY,
3219 			SPI_MEM_OP_NO_ADDR,
3220 			SPI_MEM_OP_NO_DATA);
3221 
3222 	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
3223 
3224 	ret = spi_mem_exec_op(nor->spimem, &op);
3225 	if (ret) {
3226 		dev_warn(nor->dev, "Software reset failed: %d\n", ret);
3227 		return;
3228 	}
3229 
3230 	/*
3231 	 * Software Reset is not instant, and the delay varies from flash to
3232 	 * flash. Looking at a few flashes, most range somewhere below 100
3233 	 * microseconds. So, sleep for a range of 200-400 us.
3234 	 */
3235 	usleep_range(SPI_NOR_SRST_SLEEP_MIN, SPI_NOR_SRST_SLEEP_MAX);
3236 }
3237 
3238 /* mtd suspend handler */
3239 static int spi_nor_suspend(struct mtd_info *mtd)
3240 {
3241 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3242 	int ret;
3243 
3244 	/* Disable octal DTR mode if we enabled it. */
3245 	ret = spi_nor_octal_dtr_enable(nor, false);
3246 	if (ret)
3247 		dev_err(nor->dev, "suspend() failed\n");
3248 
3249 	return ret;
3250 }
3251 
3252 /* mtd resume handler */
3253 static void spi_nor_resume(struct mtd_info *mtd)
3254 {
3255 	struct spi_nor *nor = mtd_to_spi_nor(mtd);
3256 	struct device *dev = nor->dev;
3257 	int ret;
3258 
3259 	/* re-initialize the nor chip */
3260 	ret = spi_nor_init(nor);
3261 	if (ret)
3262 		dev_err(dev, "resume() failed\n");
3263 }
3264 
3265 void spi_nor_restore(struct spi_nor *nor)
3266 {
3267 	/* restore the addressing mode */
3268 	if (nor->addr_width == 4 && !(nor->flags & SNOR_F_4B_OPCODES) &&
3269 	    nor->flags & SNOR_F_BROKEN_RESET)
3270 		nor->params->set_4byte_addr_mode(nor, false);
3271 
3272 	if (nor->flags & SNOR_F_SOFT_RESET)
3273 		spi_nor_soft_reset(nor);
3274 }
3275 EXPORT_SYMBOL_GPL(spi_nor_restore);
3276 
3277 static const struct flash_info *spi_nor_match_id(struct spi_nor *nor,
3278 						 const char *name)
3279 {
3280 	unsigned int i, j;
3281 
3282 	for (i = 0; i < ARRAY_SIZE(manufacturers); i++) {
3283 		for (j = 0; j < manufacturers[i]->nparts; j++) {
3284 			if (!strcmp(name, manufacturers[i]->parts[j].name)) {
3285 				nor->manufacturer = manufacturers[i];
3286 				return &manufacturers[i]->parts[j];
3287 			}
3288 		}
3289 	}
3290 
3291 	return NULL;
3292 }
3293 
3294 static int spi_nor_set_addr_width(struct spi_nor *nor)
3295 {
3296 	if (nor->addr_width) {
3297 		/* already configured from SFDP */
3298 	} else if (nor->read_proto == SNOR_PROTO_8_8_8_DTR) {
3299 		/*
3300 		 * In 8D-8D-8D mode, one byte takes half a cycle to transfer. So
3301 		 * in this protocol an odd address width cannot be used because
3302 		 * then the address phase would only span a cycle and a half.
3303 		 * Half a cycle would be left over. We would then have to start
3304 		 * the dummy phase in the middle of a cycle and so too the data
3305 		 * phase, and we will end the transaction with half a cycle left
3306 		 * over.
3307 		 *
3308 		 * Force all 8D-8D-8D flashes to use an address width of 4 to
3309 		 * avoid this situation.
3310 		 */
3311 		nor->addr_width = 4;
3312 	} else if (nor->info->addr_width) {
3313 		nor->addr_width = nor->info->addr_width;
3314 	} else {
3315 		nor->addr_width = 3;
3316 	}
3317 
3318 	if (nor->addr_width == 3 && nor->mtd.size > 0x1000000) {
3319 		/* enable 4-byte addressing if the device exceeds 16MiB */
3320 		nor->addr_width = 4;
3321 	}
3322 
3323 	if (nor->addr_width > SPI_NOR_MAX_ADDR_WIDTH) {
3324 		dev_dbg(nor->dev, "address width is too large: %u\n",
3325 			nor->addr_width);
3326 		return -EINVAL;
3327 	}
3328 
3329 	/* Set 4byte opcodes when possible. */
3330 	if (nor->addr_width == 4 && nor->flags & SNOR_F_4B_OPCODES &&
3331 	    !(nor->flags & SNOR_F_HAS_4BAIT))
3332 		spi_nor_set_4byte_opcodes(nor);
3333 
3334 	return 0;
3335 }
3336 
3337 static void spi_nor_debugfs_init(struct spi_nor *nor,
3338 				 const struct flash_info *info)
3339 {
3340 	struct mtd_info *mtd = &nor->mtd;
3341 
3342 	mtd->dbg.partname = info->name;
3343 	mtd->dbg.partid = devm_kasprintf(nor->dev, GFP_KERNEL, "spi-nor:%*phN",
3344 					 info->id_len, info->id);
3345 }
3346 
3347 static const struct flash_info *spi_nor_get_flash_info(struct spi_nor *nor,
3348 						       const char *name)
3349 {
3350 	const struct flash_info *info = NULL;
3351 
3352 	if (name)
3353 		info = spi_nor_match_id(nor, name);
3354 	/* Try to auto-detect if chip name wasn't specified or not found */
3355 	if (!info)
3356 		info = spi_nor_read_id(nor);
3357 	if (IS_ERR_OR_NULL(info))
3358 		return ERR_PTR(-ENOENT);
3359 
3360 	/*
3361 	 * If caller has specified name of flash model that can normally be
3362 	 * detected using JEDEC, let's verify it.
3363 	 */
3364 	if (name && info->id_len) {
3365 		const struct flash_info *jinfo;
3366 
3367 		jinfo = spi_nor_read_id(nor);
3368 		if (IS_ERR(jinfo)) {
3369 			return jinfo;
3370 		} else if (jinfo != info) {
3371 			/*
3372 			 * JEDEC knows better, so overwrite platform ID. We
3373 			 * can't trust partitions any longer, but we'll let
3374 			 * mtd apply them anyway, since some partitions may be
3375 			 * marked read-only, and we don't want to lose that
3376 			 * information, even if it's not 100% accurate.
3377 			 */
3378 			dev_warn(nor->dev, "found %s, expected %s\n",
3379 				 jinfo->name, info->name);
3380 			info = jinfo;
3381 		}
3382 	}
3383 
3384 	return info;
3385 }
3386 
3387 int spi_nor_scan(struct spi_nor *nor, const char *name,
3388 		 const struct spi_nor_hwcaps *hwcaps)
3389 {
3390 	const struct flash_info *info;
3391 	struct device *dev = nor->dev;
3392 	struct mtd_info *mtd = &nor->mtd;
3393 	struct device_node *np = spi_nor_get_flash_node(nor);
3394 	int ret;
3395 	int i;
3396 
3397 	ret = spi_nor_check(nor);
3398 	if (ret)
3399 		return ret;
3400 
3401 	/* Reset SPI protocol for all commands. */
3402 	nor->reg_proto = SNOR_PROTO_1_1_1;
3403 	nor->read_proto = SNOR_PROTO_1_1_1;
3404 	nor->write_proto = SNOR_PROTO_1_1_1;
3405 
3406 	/*
3407 	 * We need the bounce buffer early to read/write registers when going
3408 	 * through the spi-mem layer (buffers have to be DMA-able).
3409 	 * For spi-mem drivers, we'll reallocate a new buffer if
3410 	 * nor->page_size turns out to be greater than PAGE_SIZE (which
3411 	 * shouldn't happen before long since NOR pages are usually less
3412 	 * than 1KB) after spi_nor_scan() returns.
3413 	 */
3414 	nor->bouncebuf_size = PAGE_SIZE;
3415 	nor->bouncebuf = devm_kmalloc(dev, nor->bouncebuf_size,
3416 				      GFP_KERNEL);
3417 	if (!nor->bouncebuf)
3418 		return -ENOMEM;
3419 
3420 	info = spi_nor_get_flash_info(nor, name);
3421 	if (IS_ERR(info))
3422 		return PTR_ERR(info);
3423 
3424 	nor->info = info;
3425 
3426 	spi_nor_debugfs_init(nor, info);
3427 
3428 	mutex_init(&nor->lock);
3429 
3430 	/*
3431 	 * Make sure the XSR_RDY flag is set before calling
3432 	 * spi_nor_wait_till_ready(). Xilinx S3AN share MFR
3433 	 * with Atmel SPI NOR.
3434 	 */
3435 	if (info->flags & SPI_NOR_XSR_RDY)
3436 		nor->flags |=  SNOR_F_READY_XSR_RDY;
3437 
3438 	if (info->flags & SPI_NOR_HAS_LOCK)
3439 		nor->flags |= SNOR_F_HAS_LOCK;
3440 
3441 	mtd->_write = spi_nor_write;
3442 
3443 	/* Init flash parameters based on flash_info struct and SFDP */
3444 	ret = spi_nor_init_params(nor);
3445 	if (ret)
3446 		return ret;
3447 
3448 	if (!mtd->name)
3449 		mtd->name = dev_name(dev);
3450 	mtd->priv = nor;
3451 	mtd->type = MTD_NORFLASH;
3452 	mtd->writesize = nor->params->writesize;
3453 	mtd->flags = MTD_CAP_NORFLASH;
3454 	mtd->size = nor->params->size;
3455 	mtd->_erase = spi_nor_erase;
3456 	mtd->_read = spi_nor_read;
3457 	mtd->_suspend = spi_nor_suspend;
3458 	mtd->_resume = spi_nor_resume;
3459 
3460 	if (nor->params->locking_ops) {
3461 		mtd->_lock = spi_nor_lock;
3462 		mtd->_unlock = spi_nor_unlock;
3463 		mtd->_is_locked = spi_nor_is_locked;
3464 	}
3465 
3466 	if (info->flags & USE_FSR)
3467 		nor->flags |= SNOR_F_USE_FSR;
3468 	if (info->flags & SPI_NOR_HAS_TB) {
3469 		nor->flags |= SNOR_F_HAS_SR_TB;
3470 		if (info->flags & SPI_NOR_TB_SR_BIT6)
3471 			nor->flags |= SNOR_F_HAS_SR_TB_BIT6;
3472 	}
3473 
3474 	if (info->flags & NO_CHIP_ERASE)
3475 		nor->flags |= SNOR_F_NO_OP_CHIP_ERASE;
3476 	if (info->flags & USE_CLSR)
3477 		nor->flags |= SNOR_F_USE_CLSR;
3478 	if (info->flags & SPI_NOR_SWP_IS_VOLATILE)
3479 		nor->flags |= SNOR_F_SWP_IS_VOLATILE;
3480 
3481 	if (info->flags & SPI_NOR_4BIT_BP) {
3482 		nor->flags |= SNOR_F_HAS_4BIT_BP;
3483 		if (info->flags & SPI_NOR_BP3_SR_BIT6)
3484 			nor->flags |= SNOR_F_HAS_SR_BP3_BIT6;
3485 	}
3486 
3487 	if (info->flags & SPI_NOR_NO_ERASE)
3488 		mtd->flags |= MTD_NO_ERASE;
3489 
3490 	mtd->dev.parent = dev;
3491 	nor->page_size = nor->params->page_size;
3492 	mtd->writebufsize = nor->page_size;
3493 
3494 	if (of_property_read_bool(np, "broken-flash-reset"))
3495 		nor->flags |= SNOR_F_BROKEN_RESET;
3496 
3497 	/*
3498 	 * Configure the SPI memory:
3499 	 * - select op codes for (Fast) Read, Page Program and Sector Erase.
3500 	 * - set the number of dummy cycles (mode cycles + wait states).
3501 	 * - set the SPI protocols for register and memory accesses.
3502 	 */
3503 	ret = spi_nor_setup(nor, hwcaps);
3504 	if (ret)
3505 		return ret;
3506 
3507 	if (info->flags & SPI_NOR_4B_OPCODES)
3508 		nor->flags |= SNOR_F_4B_OPCODES;
3509 
3510 	if (info->flags & SPI_NOR_IO_MODE_EN_VOLATILE)
3511 		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;
3512 
3513 	ret = spi_nor_set_addr_width(nor);
3514 	if (ret)
3515 		return ret;
3516 
3517 	/* Send all the required SPI flash commands to initialize device */
3518 	ret = spi_nor_init(nor);
3519 	if (ret)
3520 		return ret;
3521 
3522 	dev_info(dev, "%s (%lld Kbytes)\n", info->name,
3523 			(long long)mtd->size >> 10);
3524 
3525 	dev_dbg(dev,
3526 		"mtd .name = %s, .size = 0x%llx (%lldMiB), "
3527 		".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n",
3528 		mtd->name, (long long)mtd->size, (long long)(mtd->size >> 20),
3529 		mtd->erasesize, mtd->erasesize / 1024, mtd->numeraseregions);
3530 
3531 	if (mtd->numeraseregions)
3532 		for (i = 0; i < mtd->numeraseregions; i++)
3533 			dev_dbg(dev,
3534 				"mtd.eraseregions[%d] = { .offset = 0x%llx, "
3535 				".erasesize = 0x%.8x (%uKiB), "
3536 				".numblocks = %d }\n",
3537 				i, (long long)mtd->eraseregions[i].offset,
3538 				mtd->eraseregions[i].erasesize,
3539 				mtd->eraseregions[i].erasesize / 1024,
3540 				mtd->eraseregions[i].numblocks);
3541 	return 0;
3542 }
3543 EXPORT_SYMBOL_GPL(spi_nor_scan);
3544 
3545 static int spi_nor_create_read_dirmap(struct spi_nor *nor)
3546 {
3547 	struct spi_mem_dirmap_info info = {
3548 		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 0),
3549 				      SPI_MEM_OP_ADDR(nor->addr_width, 0, 0),
3550 				      SPI_MEM_OP_DUMMY(nor->read_dummy, 0),
3551 				      SPI_MEM_OP_DATA_IN(0, NULL, 0)),
3552 		.offset = 0,
3553 		.length = nor->mtd.size,
3554 	};
3555 	struct spi_mem_op *op = &info.op_tmpl;
3556 
3557 	spi_nor_spimem_setup_op(nor, op, nor->read_proto);
3558 
3559 	/* convert the dummy cycles to the number of bytes */
3560 	op->dummy.nbytes = (nor->read_dummy * op->dummy.buswidth) / 8;
3561 	if (spi_nor_protocol_is_dtr(nor->read_proto))
3562 		op->dummy.nbytes *= 2;
3563 
3564 	/*
3565 	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3566 	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3567 	 * do it explicitly.
3568 	 */
3569 	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
3570 
3571 	nor->dirmap.rdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3572 						       &info);
3573 	return PTR_ERR_OR_ZERO(nor->dirmap.rdesc);
3574 }
3575 
3576 static int spi_nor_create_write_dirmap(struct spi_nor *nor)
3577 {
3578 	struct spi_mem_dirmap_info info = {
3579 		.op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 0),
3580 				      SPI_MEM_OP_ADDR(nor->addr_width, 0, 0),
3581 				      SPI_MEM_OP_NO_DUMMY,
3582 				      SPI_MEM_OP_DATA_OUT(0, NULL, 0)),
3583 		.offset = 0,
3584 		.length = nor->mtd.size,
3585 	};
3586 	struct spi_mem_op *op = &info.op_tmpl;
3587 
3588 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
3589 		op->addr.nbytes = 0;
3590 
3591 	spi_nor_spimem_setup_op(nor, op, nor->write_proto);
3592 
3593 	/*
3594 	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
3595 	 * of data bytes is non-zero, the data buswidth won't be set here. So,
3596 	 * do it explicitly.
3597 	 */
3598 	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
3599 
3600 	nor->dirmap.wdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
3601 						       &info);
3602 	return PTR_ERR_OR_ZERO(nor->dirmap.wdesc);
3603 }
3604 
3605 static int spi_nor_probe(struct spi_mem *spimem)
3606 {
3607 	struct spi_device *spi = spimem->spi;
3608 	struct flash_platform_data *data = dev_get_platdata(&spi->dev);
3609 	struct spi_nor *nor;
3610 	/*
3611 	 * Enable all caps by default. The core will mask them after
3612 	 * checking what's really supported using spi_mem_supports_op().
3613 	 */
3614 	const struct spi_nor_hwcaps hwcaps = { .mask = SNOR_HWCAPS_ALL };
3615 	char *flash_name;
3616 	int ret;
3617 
3618 	nor = devm_kzalloc(&spi->dev, sizeof(*nor), GFP_KERNEL);
3619 	if (!nor)
3620 		return -ENOMEM;
3621 
3622 	nor->spimem = spimem;
3623 	nor->dev = &spi->dev;
3624 	spi_nor_set_flash_node(nor, spi->dev.of_node);
3625 
3626 	spi_mem_set_drvdata(spimem, nor);
3627 
3628 	if (data && data->name)
3629 		nor->mtd.name = data->name;
3630 
3631 	if (!nor->mtd.name)
3632 		nor->mtd.name = spi_mem_get_name(spimem);
3633 
3634 	/*
3635 	 * For some (historical?) reason many platforms provide two different
3636 	 * names in flash_platform_data: "name" and "type". Quite often name is
3637 	 * set to "m25p80" and then "type" provides a real chip name.
3638 	 * If that's the case, respect "type" and ignore a "name".
3639 	 */
3640 	if (data && data->type)
3641 		flash_name = data->type;
3642 	else if (!strcmp(spi->modalias, "spi-nor"))
3643 		flash_name = NULL; /* auto-detect */
3644 	else
3645 		flash_name = spi->modalias;
3646 
3647 	ret = spi_nor_scan(nor, flash_name, &hwcaps);
3648 	if (ret)
3649 		return ret;
3650 
3651 	/*
3652 	 * None of the existing parts have > 512B pages, but let's play safe
3653 	 * and add this logic so that if anyone ever adds support for such
3654 	 * a NOR we don't end up with buffer overflows.
3655 	 */
3656 	if (nor->page_size > PAGE_SIZE) {
3657 		nor->bouncebuf_size = nor->page_size;
3658 		devm_kfree(nor->dev, nor->bouncebuf);
3659 		nor->bouncebuf = devm_kmalloc(nor->dev,
3660 					      nor->bouncebuf_size,
3661 					      GFP_KERNEL);
3662 		if (!nor->bouncebuf)
3663 			return -ENOMEM;
3664 	}
3665 
3666 	ret = spi_nor_create_read_dirmap(nor);
3667 	if (ret)
3668 		return ret;
3669 
3670 	ret = spi_nor_create_write_dirmap(nor);
3671 	if (ret)
3672 		return ret;
3673 
3674 	return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
3675 				   data ? data->nr_parts : 0);
3676 }
3677 
3678 static int spi_nor_remove(struct spi_mem *spimem)
3679 {
3680 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3681 
3682 	spi_nor_restore(nor);
3683 
3684 	/* Clean up MTD stuff. */
3685 	return mtd_device_unregister(&nor->mtd);
3686 }
3687 
3688 static void spi_nor_shutdown(struct spi_mem *spimem)
3689 {
3690 	struct spi_nor *nor = spi_mem_get_drvdata(spimem);
3691 
3692 	spi_nor_restore(nor);
3693 }
3694 
3695 /*
3696  * Do NOT add to this array without reading the following:
3697  *
3698  * Historically, many flash devices are bound to this driver by their name. But
3699  * since most of these flash are compatible to some extent, and their
3700  * differences can often be differentiated by the JEDEC read-ID command, we
3701  * encourage new users to add support to the spi-nor library, and simply bind
3702  * against a generic string here (e.g., "jedec,spi-nor").
3703  *
3704  * Many flash names are kept here in this list (as well as in spi-nor.c) to
3705  * keep them available as module aliases for existing platforms.
3706  */
3707 static const struct spi_device_id spi_nor_dev_ids[] = {
3708 	/*
3709 	 * Allow non-DT platform devices to bind to the "spi-nor" modalias, and
3710 	 * hack around the fact that the SPI core does not provide uevent
3711 	 * matching for .of_match_table
3712 	 */
3713 	{"spi-nor"},
3714 
3715 	/*
3716 	 * Entries not used in DTs that should be safe to drop after replacing
3717 	 * them with "spi-nor" in platform data.
3718 	 */
3719 	{"s25sl064a"},	{"w25x16"},	{"m25p10"},	{"m25px64"},
3720 
3721 	/*
3722 	 * Entries that were used in DTs without "jedec,spi-nor" fallback and
3723 	 * should be kept for backward compatibility.
3724 	 */
3725 	{"at25df321a"},	{"at25df641"},	{"at26df081a"},
3726 	{"mx25l4005a"},	{"mx25l1606e"},	{"mx25l6405d"},	{"mx25l12805d"},
3727 	{"mx25l25635e"},{"mx66l51235l"},
3728 	{"n25q064"},	{"n25q128a11"},	{"n25q128a13"},	{"n25q512a"},
3729 	{"s25fl256s1"},	{"s25fl512s"},	{"s25sl12801"},	{"s25fl008k"},
3730 	{"s25fl064k"},
3731 	{"sst25vf040b"},{"sst25vf016b"},{"sst25vf032b"},{"sst25wf040"},
3732 	{"m25p40"},	{"m25p80"},	{"m25p16"},	{"m25p32"},
3733 	{"m25p64"},	{"m25p128"},
3734 	{"w25x80"},	{"w25x32"},	{"w25q32"},	{"w25q32dw"},
3735 	{"w25q80bl"},	{"w25q128"},	{"w25q256"},
3736 
3737 	/* Flashes that can't be detected using JEDEC */
3738 	{"m25p05-nonjedec"},	{"m25p10-nonjedec"},	{"m25p20-nonjedec"},
3739 	{"m25p40-nonjedec"},	{"m25p80-nonjedec"},	{"m25p16-nonjedec"},
3740 	{"m25p32-nonjedec"},	{"m25p64-nonjedec"},	{"m25p128-nonjedec"},
3741 
3742 	/* Everspin MRAMs (non-JEDEC) */
3743 	{ "mr25h128" }, /* 128 Kib, 40 MHz */
3744 	{ "mr25h256" }, /* 256 Kib, 40 MHz */
3745 	{ "mr25h10" },  /*   1 Mib, 40 MHz */
3746 	{ "mr25h40" },  /*   4 Mib, 40 MHz */
3747 
3748 	{ },
3749 };
3750 MODULE_DEVICE_TABLE(spi, spi_nor_dev_ids);
3751 
3752 static const struct of_device_id spi_nor_of_table[] = {
3753 	/*
3754 	 * Generic compatibility for SPI NOR that can be identified by the
3755 	 * JEDEC READ ID opcode (0x9F). Use this, if possible.
3756 	 */
3757 	{ .compatible = "jedec,spi-nor" },
3758 	{ /* sentinel */ },
3759 };
3760 MODULE_DEVICE_TABLE(of, spi_nor_of_table);
3761 
3762 /*
3763  * REVISIT: many of these chips have deep power-down modes, which
3764  * should clearly be entered on suspend() to minimize power use.
3765  * And also when they're otherwise idle...
3766  */
3767 static struct spi_mem_driver spi_nor_driver = {
3768 	.spidrv = {
3769 		.driver = {
3770 			.name = "spi-nor",
3771 			.of_match_table = spi_nor_of_table,
3772 		},
3773 		.id_table = spi_nor_dev_ids,
3774 	},
3775 	.probe = spi_nor_probe,
3776 	.remove = spi_nor_remove,
3777 	.shutdown = spi_nor_shutdown,
3778 };
3779 module_spi_mem_driver(spi_nor_driver);
3780 
3781 MODULE_LICENSE("GPL v2");
3782 MODULE_AUTHOR("Huang Shijie <shijie8@gmail.com>");
3783 MODULE_AUTHOR("Mike Lavender");
3784 MODULE_DESCRIPTION("framework for SPI NOR");
3785