xref: /rk3399_rockchip-uboot/drivers/mtd/spi/spi_flash.c (revision fcc0a8774bb78a601a0d6d4e1f73dcfc07b3d4a4)
1 /*
2  * SPI Flash Core
3  *
4  * Copyright (C) 2015 Jagan Teki <jteki@openedev.com>
5  * Copyright (C) 2013 Jagannadha Sutradharudu Teki, Xilinx Inc.
6  * Copyright (C) 2010 Reinhard Meyer, EMK Elektronik
7  * Copyright (C) 2008 Atmel Corporation
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <errno.h>
14 #include <malloc.h>
15 #include <mapmem.h>
16 #include <spi.h>
17 #include <spi_flash.h>
18 #include <linux/log2.h>
19 
20 #include "sf_internal.h"
21 
22 DECLARE_GLOBAL_DATA_PTR;
23 
24 static void spi_flash_addr(u32 addr, u8 *cmd)
25 {
26 	/* cmd[0] is actual command */
27 	cmd[1] = addr >> 16;
28 	cmd[2] = addr >> 8;
29 	cmd[3] = addr >> 0;
30 }
31 
32 /* Read commands array */
33 static u8 spi_read_cmds_array[] = {
34 	CMD_READ_ARRAY_SLOW,
35 	CMD_READ_ARRAY_FAST,
36 	CMD_READ_DUAL_OUTPUT_FAST,
37 	CMD_READ_DUAL_IO_FAST,
38 	CMD_READ_QUAD_OUTPUT_FAST,
39 	CMD_READ_QUAD_IO_FAST,
40 };
41 
42 static int read_sr(struct spi_flash *flash, u8 *rs)
43 {
44 	int ret;
45 	u8 cmd;
46 
47 	cmd = CMD_READ_STATUS;
48 	ret = spi_flash_read_common(flash, &cmd, 1, rs, 1);
49 	if (ret < 0) {
50 		debug("SF: fail to read status register\n");
51 		return ret;
52 	}
53 
54 	return 0;
55 }
56 
57 static int read_fsr(struct spi_flash *flash, u8 *fsr)
58 {
59 	int ret;
60 	const u8 cmd = CMD_FLAG_STATUS;
61 
62 	ret = spi_flash_read_common(flash, &cmd, 1, fsr, 1);
63 	if (ret < 0) {
64 		debug("SF: fail to read flag status register\n");
65 		return ret;
66 	}
67 
68 	return 0;
69 }
70 
71 static int write_sr(struct spi_flash *flash, u8 ws)
72 {
73 	u8 cmd;
74 	int ret;
75 
76 	cmd = CMD_WRITE_STATUS;
77 	ret = spi_flash_write_common(flash, &cmd, 1, &ws, 1);
78 	if (ret < 0) {
79 		debug("SF: fail to write status register\n");
80 		return ret;
81 	}
82 
83 	return 0;
84 }
85 
86 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
87 static int read_cr(struct spi_flash *flash, u8 *rc)
88 {
89 	int ret;
90 	u8 cmd;
91 
92 	cmd = CMD_READ_CONFIG;
93 	ret = spi_flash_read_common(flash, &cmd, 1, rc, 1);
94 	if (ret < 0) {
95 		debug("SF: fail to read config register\n");
96 		return ret;
97 	}
98 
99 	return 0;
100 }
101 
102 static int write_cr(struct spi_flash *flash, u8 wc)
103 {
104 	u8 data[2];
105 	u8 cmd;
106 	int ret;
107 
108 	ret = read_sr(flash, &data[0]);
109 	if (ret < 0)
110 		return ret;
111 
112 	cmd = CMD_WRITE_STATUS;
113 	data[1] = wc;
114 	ret = spi_flash_write_common(flash, &cmd, 1, &data, 2);
115 	if (ret) {
116 		debug("SF: fail to write config register\n");
117 		return ret;
118 	}
119 
120 	return 0;
121 }
122 #endif
123 
124 #ifdef CONFIG_SPI_FLASH_BAR
125 static int spi_flash_write_bar(struct spi_flash *flash, u32 offset)
126 {
127 	u8 cmd, bank_sel;
128 	int ret;
129 
130 	bank_sel = offset / (SPI_FLASH_16MB_BOUN << flash->shift);
131 	if (bank_sel == flash->bank_curr)
132 		goto bar_end;
133 
134 	cmd = flash->bank_write_cmd;
135 	ret = spi_flash_write_common(flash, &cmd, 1, &bank_sel, 1);
136 	if (ret < 0) {
137 		debug("SF: fail to write bank register\n");
138 		return ret;
139 	}
140 
141 bar_end:
142 	flash->bank_curr = bank_sel;
143 	return flash->bank_curr;
144 }
145 
146 static int spi_flash_read_bar(struct spi_flash *flash, u8 idcode0)
147 {
148 	u8 curr_bank = 0;
149 	int ret;
150 
151 	if (flash->size <= SPI_FLASH_16MB_BOUN)
152 		goto bank_end;
153 
154 	switch (idcode0) {
155 	case SPI_FLASH_CFI_MFR_SPANSION:
156 		flash->bank_read_cmd = CMD_BANKADDR_BRRD;
157 		flash->bank_write_cmd = CMD_BANKADDR_BRWR;
158 		break;
159 	default:
160 		flash->bank_read_cmd = CMD_EXTNADDR_RDEAR;
161 		flash->bank_write_cmd = CMD_EXTNADDR_WREAR;
162 	}
163 
164 	ret = spi_flash_read_common(flash, &flash->bank_read_cmd, 1,
165 				    &curr_bank, 1);
166 	if (ret) {
167 		debug("SF: fail to read bank addr register\n");
168 		return ret;
169 	}
170 
171 bank_end:
172 	flash->bank_curr = curr_bank;
173 	return 0;
174 }
175 #endif
176 
177 #ifdef CONFIG_SF_DUAL_FLASH
178 static void spi_flash_dual(struct spi_flash *flash, u32 *addr)
179 {
180 	switch (flash->dual_flash) {
181 	case SF_DUAL_STACKED_FLASH:
182 		if (*addr >= (flash->size >> 1)) {
183 			*addr -= flash->size >> 1;
184 			flash->spi->flags |= SPI_XFER_U_PAGE;
185 		} else {
186 			flash->spi->flags &= ~SPI_XFER_U_PAGE;
187 		}
188 		break;
189 	case SF_DUAL_PARALLEL_FLASH:
190 		*addr >>= flash->shift;
191 		break;
192 	default:
193 		debug("SF: Unsupported dual_flash=%d\n", flash->dual_flash);
194 		break;
195 	}
196 }
197 #endif
198 
199 static int spi_flash_sr_ready(struct spi_flash *flash)
200 {
201 	u8 sr;
202 	int ret;
203 
204 	ret = read_sr(flash, &sr);
205 	if (ret < 0)
206 		return ret;
207 
208 	return !(sr & STATUS_WIP);
209 }
210 
211 static int spi_flash_fsr_ready(struct spi_flash *flash)
212 {
213 	u8 fsr;
214 	int ret;
215 
216 	ret = read_fsr(flash, &fsr);
217 	if (ret < 0)
218 		return ret;
219 
220 	return fsr & STATUS_PEC;
221 }
222 
223 static int spi_flash_ready(struct spi_flash *flash)
224 {
225 	int sr, fsr;
226 
227 	sr = spi_flash_sr_ready(flash);
228 	if (sr < 0)
229 		return sr;
230 
231 	fsr = 1;
232 	if (flash->flags & SNOR_F_USE_FSR) {
233 		fsr = spi_flash_fsr_ready(flash);
234 		if (fsr < 0)
235 			return fsr;
236 	}
237 
238 	return sr && fsr;
239 }
240 
241 static int spi_flash_cmd_wait_ready(struct spi_flash *flash,
242 					unsigned long timeout)
243 {
244 	int timebase, ret;
245 
246 	timebase = get_timer(0);
247 
248 	while (get_timer(timebase) < timeout) {
249 		ret = spi_flash_ready(flash);
250 		if (ret < 0)
251 			return ret;
252 		if (ret)
253 			return 0;
254 	}
255 
256 	printf("SF: Timeout!\n");
257 
258 	return -ETIMEDOUT;
259 }
260 
261 int spi_flash_write_common(struct spi_flash *flash, const u8 *cmd,
262 		size_t cmd_len, const void *buf, size_t buf_len)
263 {
264 	struct spi_slave *spi = flash->spi;
265 	unsigned long timeout = SPI_FLASH_PROG_TIMEOUT;
266 	int ret;
267 
268 	if (buf == NULL)
269 		timeout = SPI_FLASH_PAGE_ERASE_TIMEOUT;
270 
271 	ret = spi_claim_bus(flash->spi);
272 	if (ret) {
273 		debug("SF: unable to claim SPI bus\n");
274 		return ret;
275 	}
276 
277 	ret = spi_flash_cmd_write_enable(flash);
278 	if (ret < 0) {
279 		debug("SF: enabling write failed\n");
280 		return ret;
281 	}
282 
283 	ret = spi_flash_cmd_write(spi, cmd, cmd_len, buf, buf_len);
284 	if (ret < 0) {
285 		debug("SF: write cmd failed\n");
286 		return ret;
287 	}
288 
289 	ret = spi_flash_cmd_wait_ready(flash, timeout);
290 	if (ret < 0) {
291 		debug("SF: write %s timed out\n",
292 		      timeout == SPI_FLASH_PROG_TIMEOUT ?
293 			"program" : "page erase");
294 		return ret;
295 	}
296 
297 	spi_release_bus(spi);
298 
299 	return ret;
300 }
301 
302 int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len)
303 {
304 	u32 erase_size, erase_addr;
305 	u8 cmd[SPI_FLASH_CMD_LEN];
306 	int ret = -1;
307 
308 	erase_size = flash->erase_size;
309 	if (offset % erase_size || len % erase_size) {
310 		debug("SF: Erase offset/length not multiple of erase size\n");
311 		return -1;
312 	}
313 
314 	if (flash->flash_is_locked) {
315 		if (flash->flash_is_locked(flash, offset, len) > 0) {
316 			printf("offset 0x%x is protected and cannot be erased\n",
317 			       offset);
318 			return -EINVAL;
319 		}
320 	}
321 
322 	cmd[0] = flash->erase_cmd;
323 	while (len) {
324 		erase_addr = offset;
325 
326 #ifdef CONFIG_SF_DUAL_FLASH
327 		if (flash->dual_flash > SF_SINGLE_FLASH)
328 			spi_flash_dual(flash, &erase_addr);
329 #endif
330 #ifdef CONFIG_SPI_FLASH_BAR
331 		ret = spi_flash_write_bar(flash, erase_addr);
332 		if (ret < 0)
333 			return ret;
334 #endif
335 		spi_flash_addr(erase_addr, cmd);
336 
337 		debug("SF: erase %2x %2x %2x %2x (%x)\n", cmd[0], cmd[1],
338 		      cmd[2], cmd[3], erase_addr);
339 
340 		ret = spi_flash_write_common(flash, cmd, sizeof(cmd), NULL, 0);
341 		if (ret < 0) {
342 			debug("SF: erase failed\n");
343 			break;
344 		}
345 
346 		offset += erase_size;
347 		len -= erase_size;
348 	}
349 
350 	return ret;
351 }
352 
353 int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset,
354 		size_t len, const void *buf)
355 {
356 	unsigned long byte_addr, page_size;
357 	u32 write_addr;
358 	size_t chunk_len, actual;
359 	u8 cmd[SPI_FLASH_CMD_LEN];
360 	int ret = -1;
361 
362 	page_size = flash->page_size;
363 
364 	if (flash->flash_is_locked) {
365 		if (flash->flash_is_locked(flash, offset, len) > 0) {
366 			printf("offset 0x%x is protected and cannot be written\n",
367 			       offset);
368 			return -EINVAL;
369 		}
370 	}
371 
372 	cmd[0] = flash->write_cmd;
373 	for (actual = 0; actual < len; actual += chunk_len) {
374 		write_addr = offset;
375 
376 #ifdef CONFIG_SF_DUAL_FLASH
377 		if (flash->dual_flash > SF_SINGLE_FLASH)
378 			spi_flash_dual(flash, &write_addr);
379 #endif
380 #ifdef CONFIG_SPI_FLASH_BAR
381 		ret = spi_flash_write_bar(flash, write_addr);
382 		if (ret < 0)
383 			return ret;
384 #endif
385 		byte_addr = offset % page_size;
386 		chunk_len = min(len - actual, (size_t)(page_size - byte_addr));
387 
388 		if (flash->spi->max_write_size)
389 			chunk_len = min(chunk_len,
390 					(size_t)flash->spi->max_write_size);
391 
392 		spi_flash_addr(write_addr, cmd);
393 
394 		debug("SF: 0x%p => cmd = { 0x%02x 0x%02x%02x%02x } chunk_len = %zu\n",
395 		      buf + actual, cmd[0], cmd[1], cmd[2], cmd[3], chunk_len);
396 
397 		ret = spi_flash_write_common(flash, cmd, sizeof(cmd),
398 					buf + actual, chunk_len);
399 		if (ret < 0) {
400 			debug("SF: write failed\n");
401 			break;
402 		}
403 
404 		offset += chunk_len;
405 	}
406 
407 	return ret;
408 }
409 
410 int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd,
411 		size_t cmd_len, void *data, size_t data_len)
412 {
413 	struct spi_slave *spi = flash->spi;
414 	int ret;
415 
416 	ret = spi_claim_bus(flash->spi);
417 	if (ret) {
418 		debug("SF: unable to claim SPI bus\n");
419 		return ret;
420 	}
421 
422 	ret = spi_flash_cmd_read(spi, cmd, cmd_len, data, data_len);
423 	if (ret < 0) {
424 		debug("SF: read cmd failed\n");
425 		return ret;
426 	}
427 
428 	spi_release_bus(spi);
429 
430 	return ret;
431 }
432 
433 void __weak spi_flash_copy_mmap(void *data, void *offset, size_t len)
434 {
435 	memcpy(data, offset, len);
436 }
437 
438 int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset,
439 		size_t len, void *data)
440 {
441 	u8 *cmd, cmdsz;
442 	u32 remain_len, read_len, read_addr;
443 	int bank_sel = 0;
444 	int ret = -1;
445 
446 	/* Handle memory-mapped SPI */
447 	if (flash->memory_map) {
448 		ret = spi_claim_bus(flash->spi);
449 		if (ret) {
450 			debug("SF: unable to claim SPI bus\n");
451 			return ret;
452 		}
453 		spi_xfer(flash->spi, 0, NULL, NULL, SPI_XFER_MMAP);
454 		spi_flash_copy_mmap(data, flash->memory_map + offset, len);
455 		spi_xfer(flash->spi, 0, NULL, NULL, SPI_XFER_MMAP_END);
456 		spi_release_bus(flash->spi);
457 		return 0;
458 	}
459 
460 	cmdsz = SPI_FLASH_CMD_LEN + flash->dummy_byte;
461 	cmd = calloc(1, cmdsz);
462 	if (!cmd) {
463 		debug("SF: Failed to allocate cmd\n");
464 		return -ENOMEM;
465 	}
466 
467 	cmd[0] = flash->read_cmd;
468 	while (len) {
469 		read_addr = offset;
470 
471 #ifdef CONFIG_SF_DUAL_FLASH
472 		if (flash->dual_flash > SF_SINGLE_FLASH)
473 			spi_flash_dual(flash, &read_addr);
474 #endif
475 #ifdef CONFIG_SPI_FLASH_BAR
476 		ret = spi_flash_write_bar(flash, read_addr);
477 		if (ret < 0)
478 			return ret;
479 		bank_sel = flash->bank_curr;
480 #endif
481 		remain_len = ((SPI_FLASH_16MB_BOUN << flash->shift) *
482 				(bank_sel + 1)) - offset;
483 		if (len < remain_len)
484 			read_len = len;
485 		else
486 			read_len = remain_len;
487 
488 		spi_flash_addr(read_addr, cmd);
489 
490 		ret = spi_flash_read_common(flash, cmd, cmdsz, data, read_len);
491 		if (ret < 0) {
492 			debug("SF: read failed\n");
493 			break;
494 		}
495 
496 		offset += read_len;
497 		len -= read_len;
498 		data += read_len;
499 	}
500 
501 	free(cmd);
502 	return ret;
503 }
504 
505 #ifdef CONFIG_SPI_FLASH_SST
506 static int sst_byte_write(struct spi_flash *flash, u32 offset, const void *buf)
507 {
508 	int ret;
509 	u8 cmd[4] = {
510 		CMD_SST_BP,
511 		offset >> 16,
512 		offset >> 8,
513 		offset,
514 	};
515 
516 	debug("BP[%02x]: 0x%p => cmd = { 0x%02x 0x%06x }\n",
517 	      spi_w8r8(flash->spi, CMD_READ_STATUS), buf, cmd[0], offset);
518 
519 	ret = spi_flash_cmd_write_enable(flash);
520 	if (ret)
521 		return ret;
522 
523 	ret = spi_flash_cmd_write(flash->spi, cmd, sizeof(cmd), buf, 1);
524 	if (ret)
525 		return ret;
526 
527 	return spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
528 }
529 
530 int sst_write_wp(struct spi_flash *flash, u32 offset, size_t len,
531 		const void *buf)
532 {
533 	size_t actual, cmd_len;
534 	int ret;
535 	u8 cmd[4];
536 
537 	ret = spi_claim_bus(flash->spi);
538 	if (ret) {
539 		debug("SF: Unable to claim SPI bus\n");
540 		return ret;
541 	}
542 
543 	/* If the data is not word aligned, write out leading single byte */
544 	actual = offset % 2;
545 	if (actual) {
546 		ret = sst_byte_write(flash, offset, buf);
547 		if (ret)
548 			goto done;
549 	}
550 	offset += actual;
551 
552 	ret = spi_flash_cmd_write_enable(flash);
553 	if (ret)
554 		goto done;
555 
556 	cmd_len = 4;
557 	cmd[0] = CMD_SST_AAI_WP;
558 	cmd[1] = offset >> 16;
559 	cmd[2] = offset >> 8;
560 	cmd[3] = offset;
561 
562 	for (; actual < len - 1; actual += 2) {
563 		debug("WP[%02x]: 0x%p => cmd = { 0x%02x 0x%06x }\n",
564 		      spi_w8r8(flash->spi, CMD_READ_STATUS), buf + actual,
565 		      cmd[0], offset);
566 
567 		ret = spi_flash_cmd_write(flash->spi, cmd, cmd_len,
568 					buf + actual, 2);
569 		if (ret) {
570 			debug("SF: sst word program failed\n");
571 			break;
572 		}
573 
574 		ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
575 		if (ret)
576 			break;
577 
578 		cmd_len = 1;
579 		offset += 2;
580 	}
581 
582 	if (!ret)
583 		ret = spi_flash_cmd_write_disable(flash);
584 
585 	/* If there is a single trailing byte, write it out */
586 	if (!ret && actual != len)
587 		ret = sst_byte_write(flash, offset, buf + actual);
588 
589  done:
590 	debug("SF: sst: program %s %zu bytes @ 0x%zx\n",
591 	      ret ? "failure" : "success", len, offset - actual);
592 
593 	spi_release_bus(flash->spi);
594 	return ret;
595 }
596 
597 int sst_write_bp(struct spi_flash *flash, u32 offset, size_t len,
598 		const void *buf)
599 {
600 	size_t actual;
601 	int ret;
602 
603 	ret = spi_claim_bus(flash->spi);
604 	if (ret) {
605 		debug("SF: Unable to claim SPI bus\n");
606 		return ret;
607 	}
608 
609 	for (actual = 0; actual < len; actual++) {
610 		ret = sst_byte_write(flash, offset, buf + actual);
611 		if (ret) {
612 			debug("SF: sst byte program failed\n");
613 			break;
614 		}
615 		offset++;
616 	}
617 
618 	if (!ret)
619 		ret = spi_flash_cmd_write_disable(flash);
620 
621 	debug("SF: sst: program %s %zu bytes @ 0x%zx\n",
622 	      ret ? "failure" : "success", len, offset - actual);
623 
624 	spi_release_bus(flash->spi);
625 	return ret;
626 }
627 #endif
628 
629 #if defined(CONFIG_SPI_FLASH_STMICRO) || defined(CONFIG_SPI_FLASH_SST)
630 static void stm_get_locked_range(struct spi_flash *flash, u8 sr, loff_t *ofs,
631 				 u32 *len)
632 {
633 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
634 	int shift = ffs(mask) - 1;
635 	int pow;
636 
637 	if (!(sr & mask)) {
638 		/* No protection */
639 		*ofs = 0;
640 		*len = 0;
641 	} else {
642 		pow = ((sr & mask) ^ mask) >> shift;
643 		*len = flash->size >> pow;
644 		*ofs = flash->size - *len;
645 	}
646 }
647 
648 /*
649  * Return 1 if the entire region is locked, 0 otherwise
650  */
651 static int stm_is_locked_sr(struct spi_flash *flash, u32 ofs, u32 len,
652 			    u8 sr)
653 {
654 	loff_t lock_offs;
655 	u32 lock_len;
656 
657 	stm_get_locked_range(flash, sr, &lock_offs, &lock_len);
658 
659 	return (ofs + len <= lock_offs + lock_len) && (ofs >= lock_offs);
660 }
661 
662 /*
663  * Check if a region of the flash is (completely) locked. See stm_lock() for
664  * more info.
665  *
666  * Returns 1 if entire region is locked, 0 if any portion is unlocked, and
667  * negative on errors.
668  */
669 int stm_is_locked(struct spi_flash *flash, u32 ofs, size_t len)
670 {
671 	int status;
672 	u8 sr;
673 
674 	status = read_sr(flash, &sr);
675 	if (status < 0)
676 		return status;
677 
678 	return stm_is_locked_sr(flash, ofs, len, sr);
679 }
680 
681 /*
682  * Lock a region of the flash. Compatible with ST Micro and similar flash.
683  * Supports only the block protection bits BP{0,1,2} in the status register
684  * (SR). Does not support these features found in newer SR bitfields:
685  *   - TB: top/bottom protect - only handle TB=0 (top protect)
686  *   - SEC: sector/block protect - only handle SEC=0 (block protect)
687  *   - CMP: complement protect - only support CMP=0 (range is not complemented)
688  *
689  * Sample table portion for 8MB flash (Winbond w25q64fw):
690  *
691  *   SEC  |  TB   |  BP2  |  BP1  |  BP0  |  Prot Length  | Protected Portion
692  *  --------------------------------------------------------------------------
693  *    X   |   X   |   0   |   0   |   0   |  NONE         | NONE
694  *    0   |   0   |   0   |   0   |   1   |  128 KB       | Upper 1/64
695  *    0   |   0   |   0   |   1   |   0   |  256 KB       | Upper 1/32
696  *    0   |   0   |   0   |   1   |   1   |  512 KB       | Upper 1/16
697  *    0   |   0   |   1   |   0   |   0   |  1 MB         | Upper 1/8
698  *    0   |   0   |   1   |   0   |   1   |  2 MB         | Upper 1/4
699  *    0   |   0   |   1   |   1   |   0   |  4 MB         | Upper 1/2
700  *    X   |   X   |   1   |   1   |   1   |  8 MB         | ALL
701  *
702  * Returns negative on errors, 0 on success.
703  */
704 int stm_lock(struct spi_flash *flash, u32 ofs, size_t len)
705 {
706 	u8 status_old, status_new;
707 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
708 	u8 shift = ffs(mask) - 1, pow, val;
709 	int ret;
710 
711 	ret = read_sr(flash, &status_old);
712 	if (ret < 0)
713 		return ret;
714 
715 	/* SPI NOR always locks to the end */
716 	if (ofs + len != flash->size) {
717 		/* Does combined region extend to end? */
718 		if (!stm_is_locked_sr(flash, ofs + len, flash->size - ofs - len,
719 				      status_old))
720 			return -EINVAL;
721 		len = flash->size - ofs;
722 	}
723 
724 	/*
725 	 * Need smallest pow such that:
726 	 *
727 	 *   1 / (2^pow) <= (len / size)
728 	 *
729 	 * so (assuming power-of-2 size) we do:
730 	 *
731 	 *   pow = ceil(log2(size / len)) = log2(size) - floor(log2(len))
732 	 */
733 	pow = ilog2(flash->size) - ilog2(len);
734 	val = mask - (pow << shift);
735 	if (val & ~mask)
736 		return -EINVAL;
737 
738 	/* Don't "lock" with no region! */
739 	if (!(val & mask))
740 		return -EINVAL;
741 
742 	status_new = (status_old & ~mask) | val;
743 
744 	/* Only modify protection if it will not unlock other areas */
745 	if ((status_new & mask) <= (status_old & mask))
746 		return -EINVAL;
747 
748 	write_sr(flash, status_new);
749 
750 	return 0;
751 }
752 
753 /*
754  * Unlock a region of the flash. See stm_lock() for more info
755  *
756  * Returns negative on errors, 0 on success.
757  */
758 int stm_unlock(struct spi_flash *flash, u32 ofs, size_t len)
759 {
760 	uint8_t status_old, status_new;
761 	u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
762 	u8 shift = ffs(mask) - 1, pow, val;
763 	int ret;
764 
765 	ret = read_sr(flash, &status_old);
766 	if (ret < 0)
767 		return ret;
768 
769 	/* Cannot unlock; would unlock larger region than requested */
770 	if (stm_is_locked_sr(flash, ofs - flash->erase_size, flash->erase_size,
771 			     status_old))
772 		return -EINVAL;
773 	/*
774 	 * Need largest pow such that:
775 	 *
776 	 *   1 / (2^pow) >= (len / size)
777 	 *
778 	 * so (assuming power-of-2 size) we do:
779 	 *
780 	 *   pow = floor(log2(size / len)) = log2(size) - ceil(log2(len))
781 	 */
782 	pow = ilog2(flash->size) - order_base_2(flash->size - (ofs + len));
783 	if (ofs + len == flash->size) {
784 		val = 0; /* fully unlocked */
785 	} else {
786 		val = mask - (pow << shift);
787 		/* Some power-of-two sizes are not supported */
788 		if (val & ~mask)
789 			return -EINVAL;
790 	}
791 
792 	status_new = (status_old & ~mask) | val;
793 
794 	/* Only modify protection if it will not lock other areas */
795 	if ((status_new & mask) >= (status_old & mask))
796 		return -EINVAL;
797 
798 	write_sr(flash, status_new);
799 
800 	return 0;
801 }
802 #endif
803 
804 
805 #ifdef CONFIG_SPI_FLASH_MACRONIX
806 static int spi_flash_set_qeb_mxic(struct spi_flash *flash)
807 {
808 	u8 qeb_status;
809 	int ret;
810 
811 	ret = read_sr(flash, &qeb_status);
812 	if (ret < 0)
813 		return ret;
814 
815 	if (qeb_status & STATUS_QEB_MXIC) {
816 		debug("SF: mxic: QEB is already set\n");
817 	} else {
818 		ret = write_sr(flash, STATUS_QEB_MXIC);
819 		if (ret < 0)
820 			return ret;
821 	}
822 
823 	return ret;
824 }
825 #endif
826 
827 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
828 static int spi_flash_set_qeb_winspan(struct spi_flash *flash)
829 {
830 	u8 qeb_status;
831 	int ret;
832 
833 	ret = read_cr(flash, &qeb_status);
834 	if (ret < 0)
835 		return ret;
836 
837 	if (qeb_status & STATUS_QEB_WINSPAN) {
838 		debug("SF: winspan: QEB is already set\n");
839 	} else {
840 		ret = write_cr(flash, STATUS_QEB_WINSPAN);
841 		if (ret < 0)
842 			return ret;
843 	}
844 
845 	return ret;
846 }
847 #endif
848 
849 static int spi_flash_set_qeb(struct spi_flash *flash, u8 idcode0)
850 {
851 	switch (idcode0) {
852 #ifdef CONFIG_SPI_FLASH_MACRONIX
853 	case SPI_FLASH_CFI_MFR_MACRONIX:
854 		return spi_flash_set_qeb_mxic(flash);
855 #endif
856 #if defined(CONFIG_SPI_FLASH_SPANSION) || defined(CONFIG_SPI_FLASH_WINBOND)
857 	case SPI_FLASH_CFI_MFR_SPANSION:
858 	case SPI_FLASH_CFI_MFR_WINBOND:
859 		return spi_flash_set_qeb_winspan(flash);
860 #endif
861 #ifdef CONFIG_SPI_FLASH_STMICRO
862 	case SPI_FLASH_CFI_MFR_STMICRO:
863 		debug("SF: QEB is volatile for %02x flash\n", idcode0);
864 		return 0;
865 #endif
866 	default:
867 		printf("SF: Need set QEB func for %02x flash\n", idcode0);
868 		return -1;
869 	}
870 }
871 
872 #if CONFIG_IS_ENABLED(OF_CONTROL)
873 int spi_flash_decode_fdt(const void *blob, struct spi_flash *flash)
874 {
875 	fdt_addr_t addr;
876 	fdt_size_t size;
877 	int node;
878 
879 	/* If there is no node, do nothing */
880 	node = fdtdec_next_compatible(blob, 0, COMPAT_GENERIC_SPI_FLASH);
881 	if (node < 0)
882 		return 0;
883 
884 	addr = fdtdec_get_addr_size(blob, node, "memory-map", &size);
885 	if (addr == FDT_ADDR_T_NONE) {
886 		debug("%s: Cannot decode address\n", __func__);
887 		return 0;
888 	}
889 
890 	if (flash->size != size) {
891 		debug("%s: Memory map must cover entire device\n", __func__);
892 		return -1;
893 	}
894 	flash->memory_map = map_sysmem(addr, size);
895 
896 	return 0;
897 }
898 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
899 
900 int spi_flash_scan(struct spi_flash *flash)
901 {
902 	struct spi_slave *spi = flash->spi;
903 	const struct spi_flash_params *params;
904 	u16 jedec, ext_jedec;
905 	u8 idcode[5];
906 	u8 cmd;
907 	int ret;
908 
909 	/* Read the ID codes */
910 	ret = spi_flash_cmd(spi, CMD_READ_ID, idcode, sizeof(idcode));
911 	if (ret) {
912 		printf("SF: Failed to get idcodes\n");
913 		return -EINVAL;
914 	}
915 
916 #ifdef DEBUG
917 	printf("SF: Got idcodes\n");
918 	print_buffer(0, idcode, 1, sizeof(idcode), 0);
919 #endif
920 
921 	jedec = idcode[1] << 8 | idcode[2];
922 	ext_jedec = idcode[3] << 8 | idcode[4];
923 
924 	/* Validate params from spi_flash_params table */
925 	params = spi_flash_params_table;
926 	for (; params->name != NULL; params++) {
927 		if ((params->jedec >> 16) == idcode[0]) {
928 			if ((params->jedec & 0xFFFF) == jedec) {
929 				if (params->ext_jedec == 0)
930 					break;
931 				else if (params->ext_jedec == ext_jedec)
932 					break;
933 			}
934 		}
935 	}
936 
937 	if (!params->name) {
938 		printf("SF: Unsupported flash IDs: ");
939 		printf("manuf %02x, jedec %04x, ext_jedec %04x\n",
940 		       idcode[0], jedec, ext_jedec);
941 		return -EPROTONOSUPPORT;
942 	}
943 
944 	/* Flash powers up read-only, so clear BP# bits */
945 	if (idcode[0] == SPI_FLASH_CFI_MFR_ATMEL ||
946 	    idcode[0] == SPI_FLASH_CFI_MFR_MACRONIX ||
947 	    idcode[0] == SPI_FLASH_CFI_MFR_SST)
948 		write_sr(flash, 0);
949 
950 	/* Assign spi data */
951 	flash->name = params->name;
952 	flash->memory_map = spi->memory_map;
953 	flash->dual_flash = flash->spi->option;
954 
955 	/* Assign spi flash flags */
956 	if (params->flags & SST_WR)
957 		flash->flags |= SNOR_F_SST_WR;
958 
959 	/* Assign spi_flash ops */
960 #ifndef CONFIG_DM_SPI_FLASH
961 	flash->write = spi_flash_cmd_write_ops;
962 #if defined(CONFIG_SPI_FLASH_SST)
963 	if (flash->flags & SNOR_F_SST_WR) {
964 		if (flash->spi->op_mode_tx & SPI_OPM_TX_BP)
965 			flash->write = sst_write_bp;
966 		else
967 			flash->write = sst_write_wp;
968 	}
969 #endif
970 	flash->erase = spi_flash_cmd_erase_ops;
971 	flash->read = spi_flash_cmd_read_ops;
972 #endif
973 
974 	/* lock hooks are flash specific - assign them based on idcode0 */
975 	switch (idcode[0]) {
976 #if defined(CONFIG_SPI_FLASH_STMICRO) || defined(CONFIG_SPI_FLASH_SST)
977 	case SPI_FLASH_CFI_MFR_STMICRO:
978 	case SPI_FLASH_CFI_MFR_SST:
979 		flash->flash_lock = stm_lock;
980 		flash->flash_unlock = stm_unlock;
981 		flash->flash_is_locked = stm_is_locked;
982 #endif
983 		break;
984 	default:
985 		debug("SF: Lock ops not supported for %02x flash\n", idcode[0]);
986 	}
987 
988 	/* Compute the flash size */
989 	flash->shift = (flash->dual_flash & SF_DUAL_PARALLEL_FLASH) ? 1 : 0;
990 	/*
991 	 * The Spansion S25FL032P and S25FL064P have 256b pages, yet use the
992 	 * 0x4d00 Extended JEDEC code. The rest of the Spansion flashes with
993 	 * the 0x4d00 Extended JEDEC code have 512b pages. All of the others
994 	 * have 256b pages.
995 	 */
996 	if (ext_jedec == 0x4d00) {
997 		if ((jedec == 0x0215) || (jedec == 0x216))
998 			flash->page_size = 256;
999 		else
1000 			flash->page_size = 512;
1001 	} else {
1002 		flash->page_size = 256;
1003 	}
1004 	flash->page_size <<= flash->shift;
1005 	flash->sector_size = params->sector_size << flash->shift;
1006 	flash->size = flash->sector_size * params->nr_sectors << flash->shift;
1007 #ifdef CONFIG_SF_DUAL_FLASH
1008 	if (flash->dual_flash & SF_DUAL_STACKED_FLASH)
1009 		flash->size <<= 1;
1010 #endif
1011 
1012 	/* Compute erase sector and command */
1013 	if (params->flags & SECT_4K) {
1014 		flash->erase_cmd = CMD_ERASE_4K;
1015 		flash->erase_size = 4096 << flash->shift;
1016 	} else if (params->flags & SECT_32K) {
1017 		flash->erase_cmd = CMD_ERASE_32K;
1018 		flash->erase_size = 32768 << flash->shift;
1019 	} else {
1020 		flash->erase_cmd = CMD_ERASE_64K;
1021 		flash->erase_size = flash->sector_size;
1022 	}
1023 
1024 	/* Now erase size becomes valid sector size */
1025 	flash->sector_size = flash->erase_size;
1026 
1027 	/* Look for the fastest read cmd */
1028 	cmd = fls(params->e_rd_cmd & flash->spi->op_mode_rx);
1029 	if (cmd) {
1030 		cmd = spi_read_cmds_array[cmd - 1];
1031 		flash->read_cmd = cmd;
1032 	} else {
1033 		/* Go for default supported read cmd */
1034 		flash->read_cmd = CMD_READ_ARRAY_FAST;
1035 	}
1036 
1037 	/* Not require to look for fastest only two write cmds yet */
1038 	if (params->flags & WR_QPP && flash->spi->op_mode_tx & SPI_OPM_TX_QPP)
1039 		flash->write_cmd = CMD_QUAD_PAGE_PROGRAM;
1040 	else
1041 		/* Go for default supported write cmd */
1042 		flash->write_cmd = CMD_PAGE_PROGRAM;
1043 
1044 	/* Set the quad enable bit - only for quad commands */
1045 	if ((flash->read_cmd == CMD_READ_QUAD_OUTPUT_FAST) ||
1046 	    (flash->read_cmd == CMD_READ_QUAD_IO_FAST) ||
1047 	    (flash->write_cmd == CMD_QUAD_PAGE_PROGRAM)) {
1048 		ret = spi_flash_set_qeb(flash, idcode[0]);
1049 		if (ret) {
1050 			debug("SF: Fail to set QEB for %02x\n", idcode[0]);
1051 			return -EINVAL;
1052 		}
1053 	}
1054 
1055 	/* Read dummy_byte: dummy byte is determined based on the
1056 	 * dummy cycles of a particular command.
1057 	 * Fast commands - dummy_byte = dummy_cycles/8
1058 	 * I/O commands- dummy_byte = (dummy_cycles * no.of lines)/8
1059 	 * For I/O commands except cmd[0] everything goes on no.of lines
1060 	 * based on particular command but incase of fast commands except
1061 	 * data all go on single line irrespective of command.
1062 	 */
1063 	switch (flash->read_cmd) {
1064 	case CMD_READ_QUAD_IO_FAST:
1065 		flash->dummy_byte = 2;
1066 		break;
1067 	case CMD_READ_ARRAY_SLOW:
1068 		flash->dummy_byte = 0;
1069 		break;
1070 	default:
1071 		flash->dummy_byte = 1;
1072 	}
1073 
1074 #ifdef CONFIG_SPI_FLASH_STMICRO
1075 	if (params->flags & E_FSR)
1076 		flash->flags |= SNOR_F_USE_FSR;
1077 #endif
1078 
1079 	/* Configure the BAR - discover bank cmds and read current bank */
1080 #ifdef CONFIG_SPI_FLASH_BAR
1081 	ret = spi_flash_read_bar(flash, idcode[0]);
1082 	if (ret < 0)
1083 		return ret;
1084 #endif
1085 
1086 #if CONFIG_IS_ENABLED(OF_CONTROL)
1087 	ret = spi_flash_decode_fdt(gd->fdt_blob, flash);
1088 	if (ret) {
1089 		debug("SF: FDT decode error\n");
1090 		return -EINVAL;
1091 	}
1092 #endif
1093 
1094 #ifndef CONFIG_SPL_BUILD
1095 	printf("SF: Detected %s with page size ", flash->name);
1096 	print_size(flash->page_size, ", erase size ");
1097 	print_size(flash->erase_size, ", total ");
1098 	print_size(flash->size, "");
1099 	if (flash->memory_map)
1100 		printf(", mapped at %p", flash->memory_map);
1101 	puts("\n");
1102 #endif
1103 
1104 #ifndef CONFIG_SPI_FLASH_BAR
1105 	if (((flash->dual_flash == SF_SINGLE_FLASH) &&
1106 	     (flash->size > SPI_FLASH_16MB_BOUN)) ||
1107 	     ((flash->dual_flash > SF_SINGLE_FLASH) &&
1108 	     (flash->size > SPI_FLASH_16MB_BOUN << 1))) {
1109 		puts("SF: Warning - Only lower 16MiB accessible,");
1110 		puts(" Full access #define CONFIG_SPI_FLASH_BAR\n");
1111 	}
1112 #endif
1113 
1114 	return ret;
1115 }
1116