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1 /*
2  *  Overview:
3  *   This is the generic MTD driver for NAND flash devices. It should be
4  *   capable of working with almost all NAND chips currently available.
5  *
6  *	Additional technical information is available on
7  *	http://www.linux-mtd.infradead.org/doc/nand.html
8  *
9  *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
10  *		  2002-2006 Thomas Gleixner (tglx@linutronix.de)
11  *
12  *  Credits:
13  *	David Woodhouse for adding multichip support
14  *
15  *	Aleph One Ltd. and Toby Churchill Ltd. for supporting the
16  *	rework for 2K page size chips
17  *
18  *  TODO:
19  *	Enable cached programming for 2k page size chips
20  *	Check, if mtd->ecctype should be set to MTD_ECC_HW
21  *	if we have HW ECC support.
22  *	BBT table is not serialized, has to be fixed
23  *
24  * This program is free software; you can redistribute it and/or modify
25  * it under the terms of the GNU General Public License version 2 as
26  * published by the Free Software Foundation.
27  *
28  */
29 
30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31 
32 #include <linux/module.h>
33 #include <linux/delay.h>
34 #include <linux/errno.h>
35 #include <linux/err.h>
36 #include <linux/sched.h>
37 #include <linux/slab.h>
38 #include <linux/mm.h>
39 #include <linux/types.h>
40 #include <linux/mtd/mtd.h>
41 #include <linux/mtd/nand.h>
42 #include <linux/mtd/nand_ecc.h>
43 #include <linux/mtd/nand_bch.h>
44 #include <linux/interrupt.h>
45 #include <linux/bitops.h>
46 #include <linux/leds.h>
47 #include <linux/io.h>
48 #include <linux/mtd/partitions.h>
49 #include <linux/of_mtd.h>
50 
51 /* Define default oob placement schemes for large and small page devices */
52 static struct nand_ecclayout nand_oob_8 = {
53 	.eccbytes = 3,
54 	.eccpos = {0, 1, 2},
55 	.oobfree = {
56 		{.offset = 3,
57 		 .length = 2},
58 		{.offset = 6,
59 		 .length = 2} }
60 };
61 
62 static struct nand_ecclayout nand_oob_16 = {
63 	.eccbytes = 6,
64 	.eccpos = {0, 1, 2, 3, 6, 7},
65 	.oobfree = {
66 		{.offset = 8,
67 		 . length = 8} }
68 };
69 
70 static struct nand_ecclayout nand_oob_64 = {
71 	.eccbytes = 24,
72 	.eccpos = {
73 		   40, 41, 42, 43, 44, 45, 46, 47,
74 		   48, 49, 50, 51, 52, 53, 54, 55,
75 		   56, 57, 58, 59, 60, 61, 62, 63},
76 	.oobfree = {
77 		{.offset = 2,
78 		 .length = 38} }
79 };
80 
81 static struct nand_ecclayout nand_oob_128 = {
82 	.eccbytes = 48,
83 	.eccpos = {
84 		   80, 81, 82, 83, 84, 85, 86, 87,
85 		   88, 89, 90, 91, 92, 93, 94, 95,
86 		   96, 97, 98, 99, 100, 101, 102, 103,
87 		   104, 105, 106, 107, 108, 109, 110, 111,
88 		   112, 113, 114, 115, 116, 117, 118, 119,
89 		   120, 121, 122, 123, 124, 125, 126, 127},
90 	.oobfree = {
91 		{.offset = 2,
92 		 .length = 78} }
93 };
94 
95 static int nand_get_device(struct mtd_info *mtd, int new_state);
96 
97 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
98 			     struct mtd_oob_ops *ops);
99 
100 /*
101  * For devices which display every fart in the system on a separate LED. Is
102  * compiled away when LED support is disabled.
103  */
104 DEFINE_LED_TRIGGER(nand_led_trigger);
105 
check_offs_len(struct mtd_info * mtd,loff_t ofs,uint64_t len)106 static int check_offs_len(struct mtd_info *mtd,
107 					loff_t ofs, uint64_t len)
108 {
109 	struct nand_chip *chip = mtd->priv;
110 	int ret = 0;
111 
112 	/* Start address must align on block boundary */
113 	if (ofs & ((1ULL << chip->phys_erase_shift) - 1)) {
114 		pr_debug("%s: unaligned address\n", __func__);
115 		ret = -EINVAL;
116 	}
117 
118 	/* Length must align on block boundary */
119 	if (len & ((1ULL << chip->phys_erase_shift) - 1)) {
120 		pr_debug("%s: length not block aligned\n", __func__);
121 		ret = -EINVAL;
122 	}
123 
124 	return ret;
125 }
126 
127 /**
128  * nand_release_device - [GENERIC] release chip
129  * @mtd: MTD device structure
130  *
131  * Release chip lock and wake up anyone waiting on the device.
132  */
nand_release_device(struct mtd_info * mtd)133 static void nand_release_device(struct mtd_info *mtd)
134 {
135 	struct nand_chip *chip = mtd->priv;
136 
137 	/* Release the controller and the chip */
138 	spin_lock(&chip->controller->lock);
139 	chip->controller->active = NULL;
140 	chip->state = FL_READY;
141 	wake_up(&chip->controller->wq);
142 	spin_unlock(&chip->controller->lock);
143 }
144 
145 /**
146  * nand_read_byte - [DEFAULT] read one byte from the chip
147  * @mtd: MTD device structure
148  *
149  * Default read function for 8bit buswidth
150  */
nand_read_byte(struct mtd_info * mtd)151 static uint8_t nand_read_byte(struct mtd_info *mtd)
152 {
153 	struct nand_chip *chip = mtd->priv;
154 	return readb(chip->IO_ADDR_R);
155 }
156 
157 /**
158  * nand_read_byte16 - [DEFAULT] read one byte endianness aware from the chip
159  * @mtd: MTD device structure
160  *
161  * Default read function for 16bit buswidth with endianness conversion.
162  *
163  */
nand_read_byte16(struct mtd_info * mtd)164 static uint8_t nand_read_byte16(struct mtd_info *mtd)
165 {
166 	struct nand_chip *chip = mtd->priv;
167 	return (uint8_t) cpu_to_le16(readw(chip->IO_ADDR_R));
168 }
169 
170 /**
171  * nand_read_word - [DEFAULT] read one word from the chip
172  * @mtd: MTD device structure
173  *
174  * Default read function for 16bit buswidth without endianness conversion.
175  */
nand_read_word(struct mtd_info * mtd)176 static u16 nand_read_word(struct mtd_info *mtd)
177 {
178 	struct nand_chip *chip = mtd->priv;
179 	return readw(chip->IO_ADDR_R);
180 }
181 
182 /**
183  * nand_select_chip - [DEFAULT] control CE line
184  * @mtd: MTD device structure
185  * @chipnr: chipnumber to select, -1 for deselect
186  *
187  * Default select function for 1 chip devices.
188  */
nand_select_chip(struct mtd_info * mtd,int chipnr)189 static void nand_select_chip(struct mtd_info *mtd, int chipnr)
190 {
191 	struct nand_chip *chip = mtd->priv;
192 
193 	switch (chipnr) {
194 	case -1:
195 		chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
196 		break;
197 	case 0:
198 		break;
199 
200 	default:
201 		BUG();
202 	}
203 }
204 
205 /**
206  * nand_write_byte - [DEFAULT] write single byte to chip
207  * @mtd: MTD device structure
208  * @byte: value to write
209  *
210  * Default function to write a byte to I/O[7:0]
211  */
nand_write_byte(struct mtd_info * mtd,uint8_t byte)212 static void nand_write_byte(struct mtd_info *mtd, uint8_t byte)
213 {
214 	struct nand_chip *chip = mtd->priv;
215 
216 	chip->write_buf(mtd, &byte, 1);
217 }
218 
219 /**
220  * nand_write_byte16 - [DEFAULT] write single byte to a chip with width 16
221  * @mtd: MTD device structure
222  * @byte: value to write
223  *
224  * Default function to write a byte to I/O[7:0] on a 16-bit wide chip.
225  */
nand_write_byte16(struct mtd_info * mtd,uint8_t byte)226 static void nand_write_byte16(struct mtd_info *mtd, uint8_t byte)
227 {
228 	struct nand_chip *chip = mtd->priv;
229 	uint16_t word = byte;
230 
231 	/*
232 	 * It's not entirely clear what should happen to I/O[15:8] when writing
233 	 * a byte. The ONFi spec (Revision 3.1; 2012-09-19, Section 2.16) reads:
234 	 *
235 	 *    When the host supports a 16-bit bus width, only data is
236 	 *    transferred at the 16-bit width. All address and command line
237 	 *    transfers shall use only the lower 8-bits of the data bus. During
238 	 *    command transfers, the host may place any value on the upper
239 	 *    8-bits of the data bus. During address transfers, the host shall
240 	 *    set the upper 8-bits of the data bus to 00h.
241 	 *
242 	 * One user of the write_byte callback is nand_onfi_set_features. The
243 	 * four parameters are specified to be written to I/O[7:0], but this is
244 	 * neither an address nor a command transfer. Let's assume a 0 on the
245 	 * upper I/O lines is OK.
246 	 */
247 	chip->write_buf(mtd, (uint8_t *)&word, 2);
248 }
249 
250 /**
251  * nand_write_buf - [DEFAULT] write buffer to chip
252  * @mtd: MTD device structure
253  * @buf: data buffer
254  * @len: number of bytes to write
255  *
256  * Default write function for 8bit buswidth.
257  */
nand_write_buf(struct mtd_info * mtd,const uint8_t * buf,int len)258 static void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
259 {
260 	struct nand_chip *chip = mtd->priv;
261 
262 	iowrite8_rep(chip->IO_ADDR_W, buf, len);
263 }
264 
265 /**
266  * nand_read_buf - [DEFAULT] read chip data into buffer
267  * @mtd: MTD device structure
268  * @buf: buffer to store date
269  * @len: number of bytes to read
270  *
271  * Default read function for 8bit buswidth.
272  */
nand_read_buf(struct mtd_info * mtd,uint8_t * buf,int len)273 static void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
274 {
275 	struct nand_chip *chip = mtd->priv;
276 
277 	ioread8_rep(chip->IO_ADDR_R, buf, len);
278 }
279 
280 /**
281  * nand_write_buf16 - [DEFAULT] write buffer to chip
282  * @mtd: MTD device structure
283  * @buf: data buffer
284  * @len: number of bytes to write
285  *
286  * Default write function for 16bit buswidth.
287  */
nand_write_buf16(struct mtd_info * mtd,const uint8_t * buf,int len)288 static void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
289 {
290 	struct nand_chip *chip = mtd->priv;
291 	u16 *p = (u16 *) buf;
292 
293 	iowrite16_rep(chip->IO_ADDR_W, p, len >> 1);
294 }
295 
296 /**
297  * nand_read_buf16 - [DEFAULT] read chip data into buffer
298  * @mtd: MTD device structure
299  * @buf: buffer to store date
300  * @len: number of bytes to read
301  *
302  * Default read function for 16bit buswidth.
303  */
nand_read_buf16(struct mtd_info * mtd,uint8_t * buf,int len)304 static void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
305 {
306 	struct nand_chip *chip = mtd->priv;
307 	u16 *p = (u16 *) buf;
308 
309 	ioread16_rep(chip->IO_ADDR_R, p, len >> 1);
310 }
311 
312 /**
313  * nand_block_bad - [DEFAULT] Read bad block marker from the chip
314  * @mtd: MTD device structure
315  * @ofs: offset from device start
316  * @getchip: 0, if the chip is already selected
317  *
318  * Check, if the block is bad.
319  */
nand_block_bad(struct mtd_info * mtd,loff_t ofs,int getchip)320 static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
321 {
322 	int page, chipnr, res = 0, i = 0;
323 	struct nand_chip *chip = mtd->priv;
324 	u16 bad;
325 
326 	if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
327 		ofs += mtd->erasesize - mtd->writesize;
328 
329 	page = (int)(ofs >> chip->page_shift) & chip->pagemask;
330 
331 	if (getchip) {
332 		chipnr = (int)(ofs >> chip->chip_shift);
333 
334 		nand_get_device(mtd, FL_READING);
335 
336 		/* Select the NAND device */
337 		chip->select_chip(mtd, chipnr);
338 	}
339 
340 	do {
341 		if (chip->options & NAND_BUSWIDTH_16) {
342 			chip->cmdfunc(mtd, NAND_CMD_READOOB,
343 					chip->badblockpos & 0xFE, page);
344 			bad = cpu_to_le16(chip->read_word(mtd));
345 			if (chip->badblockpos & 0x1)
346 				bad >>= 8;
347 			else
348 				bad &= 0xFF;
349 		} else {
350 			chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos,
351 					page);
352 			bad = chip->read_byte(mtd);
353 		}
354 
355 		if (likely(chip->badblockbits == 8))
356 			res = bad != 0xFF;
357 		else
358 			res = hweight8(bad) < chip->badblockbits;
359 		ofs += mtd->writesize;
360 		page = (int)(ofs >> chip->page_shift) & chip->pagemask;
361 		i++;
362 	} while (!res && i < 2 && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE));
363 
364 	if (getchip) {
365 		chip->select_chip(mtd, -1);
366 		nand_release_device(mtd);
367 	}
368 
369 	return res;
370 }
371 
372 /**
373  * nand_default_block_markbad - [DEFAULT] mark a block bad via bad block marker
374  * @mtd: MTD device structure
375  * @ofs: offset from device start
376  *
377  * This is the default implementation, which can be overridden by a hardware
378  * specific driver. It provides the details for writing a bad block marker to a
379  * block.
380  */
nand_default_block_markbad(struct mtd_info * mtd,loff_t ofs)381 static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
382 {
383 	struct nand_chip *chip = mtd->priv;
384 	struct mtd_oob_ops ops;
385 	uint8_t buf[2] = { 0, 0 };
386 	int ret = 0, res, i = 0;
387 
388 	memset(&ops, 0, sizeof(ops));
389 	ops.oobbuf = buf;
390 	ops.ooboffs = chip->badblockpos;
391 	if (chip->options & NAND_BUSWIDTH_16) {
392 		ops.ooboffs &= ~0x01;
393 		ops.len = ops.ooblen = 2;
394 	} else {
395 		ops.len = ops.ooblen = 1;
396 	}
397 	ops.mode = MTD_OPS_PLACE_OOB;
398 
399 	/* Write to first/last page(s) if necessary */
400 	if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
401 		ofs += mtd->erasesize - mtd->writesize;
402 	do {
403 		res = nand_do_write_oob(mtd, ofs, &ops);
404 		if (!ret)
405 			ret = res;
406 
407 		i++;
408 		ofs += mtd->writesize;
409 	} while ((chip->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);
410 
411 	return ret;
412 }
413 
414 /**
415  * nand_block_markbad_lowlevel - mark a block bad
416  * @mtd: MTD device structure
417  * @ofs: offset from device start
418  *
419  * This function performs the generic NAND bad block marking steps (i.e., bad
420  * block table(s) and/or marker(s)). We only allow the hardware driver to
421  * specify how to write bad block markers to OOB (chip->block_markbad).
422  *
423  * We try operations in the following order:
424  *  (1) erase the affected block, to allow OOB marker to be written cleanly
425  *  (2) write bad block marker to OOB area of affected block (unless flag
426  *      NAND_BBT_NO_OOB_BBM is present)
427  *  (3) update the BBT
428  * Note that we retain the first error encountered in (2) or (3), finish the
429  * procedures, and dump the error in the end.
430 */
nand_block_markbad_lowlevel(struct mtd_info * mtd,loff_t ofs)431 static int nand_block_markbad_lowlevel(struct mtd_info *mtd, loff_t ofs)
432 {
433 	struct nand_chip *chip = mtd->priv;
434 	int res, ret = 0;
435 
436 	if (!(chip->bbt_options & NAND_BBT_NO_OOB_BBM)) {
437 		struct erase_info einfo;
438 
439 		/* Attempt erase before marking OOB */
440 		memset(&einfo, 0, sizeof(einfo));
441 		einfo.mtd = mtd;
442 		einfo.addr = ofs;
443 		einfo.len = 1ULL << chip->phys_erase_shift;
444 		nand_erase_nand(mtd, &einfo, 0);
445 
446 		/* Write bad block marker to OOB */
447 		nand_get_device(mtd, FL_WRITING);
448 		ret = chip->block_markbad(mtd, ofs);
449 		nand_release_device(mtd);
450 	}
451 
452 	/* Mark block bad in BBT */
453 	if (chip->bbt) {
454 		res = nand_markbad_bbt(mtd, ofs);
455 		if (!ret)
456 			ret = res;
457 	}
458 
459 	if (!ret)
460 		mtd->ecc_stats.badblocks++;
461 
462 	return ret;
463 }
464 
465 /**
466  * nand_check_wp - [GENERIC] check if the chip is write protected
467  * @mtd: MTD device structure
468  *
469  * Check, if the device is write protected. The function expects, that the
470  * device is already selected.
471  */
nand_check_wp(struct mtd_info * mtd)472 static int nand_check_wp(struct mtd_info *mtd)
473 {
474 	struct nand_chip *chip = mtd->priv;
475 
476 	/* Broken xD cards report WP despite being writable */
477 	if (chip->options & NAND_BROKEN_XD)
478 		return 0;
479 
480 	/* Check the WP bit */
481 	chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
482 	return (chip->read_byte(mtd) & NAND_STATUS_WP) ? 0 : 1;
483 }
484 
485 /**
486  * nand_block_isreserved - [GENERIC] Check if a block is marked reserved.
487  * @mtd: MTD device structure
488  * @ofs: offset from device start
489  *
490  * Check if the block is marked as reserved.
491  */
nand_block_isreserved(struct mtd_info * mtd,loff_t ofs)492 static int nand_block_isreserved(struct mtd_info *mtd, loff_t ofs)
493 {
494 	struct nand_chip *chip = mtd->priv;
495 
496 	if (!chip->bbt)
497 		return 0;
498 	/* Return info from the table */
499 	return nand_isreserved_bbt(mtd, ofs);
500 }
501 
502 /**
503  * nand_block_checkbad - [GENERIC] Check if a block is marked bad
504  * @mtd: MTD device structure
505  * @ofs: offset from device start
506  * @getchip: 0, if the chip is already selected
507  * @allowbbt: 1, if its allowed to access the bbt area
508  *
509  * Check, if the block is bad. Either by reading the bad block table or
510  * calling of the scan function.
511  */
nand_block_checkbad(struct mtd_info * mtd,loff_t ofs,int getchip,int allowbbt)512 static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip,
513 			       int allowbbt)
514 {
515 	struct nand_chip *chip = mtd->priv;
516 
517 	if (!chip->bbt)
518 		return chip->block_bad(mtd, ofs, getchip);
519 
520 	/* Return info from the table */
521 	return nand_isbad_bbt(mtd, ofs, allowbbt);
522 }
523 
524 /**
525  * panic_nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
526  * @mtd: MTD device structure
527  * @timeo: Timeout
528  *
529  * Helper function for nand_wait_ready used when needing to wait in interrupt
530  * context.
531  */
panic_nand_wait_ready(struct mtd_info * mtd,unsigned long timeo)532 static void panic_nand_wait_ready(struct mtd_info *mtd, unsigned long timeo)
533 {
534 	struct nand_chip *chip = mtd->priv;
535 	int i;
536 
537 	/* Wait for the device to get ready */
538 	for (i = 0; i < timeo; i++) {
539 		if (chip->dev_ready(mtd))
540 			break;
541 		touch_softlockup_watchdog();
542 		mdelay(1);
543 	}
544 }
545 
546 /**
547  * nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
548  * @mtd: MTD device structure
549  *
550  * Wait for the ready pin after a command, and warn if a timeout occurs.
551  */
nand_wait_ready(struct mtd_info * mtd)552 void nand_wait_ready(struct mtd_info *mtd)
553 {
554 	struct nand_chip *chip = mtd->priv;
555 	unsigned long timeo = 400;
556 
557 	if (in_interrupt() || oops_in_progress)
558 		return panic_nand_wait_ready(mtd, timeo);
559 
560 	led_trigger_event(nand_led_trigger, LED_FULL);
561 	/* Wait until command is processed or timeout occurs */
562 	timeo = jiffies + msecs_to_jiffies(timeo);
563 	do {
564 		if (chip->dev_ready(mtd))
565 			goto out;
566 		cond_resched();
567 	} while (time_before(jiffies, timeo));
568 
569 	pr_warn_ratelimited(
570 		"timeout while waiting for chip to become ready\n");
571 out:
572 	led_trigger_event(nand_led_trigger, LED_OFF);
573 }
574 EXPORT_SYMBOL_GPL(nand_wait_ready);
575 
576 /**
577  * nand_wait_status_ready - [GENERIC] Wait for the ready status after commands.
578  * @mtd: MTD device structure
579  * @timeo: Timeout in ms
580  *
581  * Wait for status ready (i.e. command done) or timeout.
582  */
nand_wait_status_ready(struct mtd_info * mtd,unsigned long timeo)583 static void nand_wait_status_ready(struct mtd_info *mtd, unsigned long timeo)
584 {
585 	register struct nand_chip *chip = mtd->priv;
586 
587 	timeo = jiffies + msecs_to_jiffies(timeo);
588 	do {
589 		if ((chip->read_byte(mtd) & NAND_STATUS_READY))
590 			break;
591 		touch_softlockup_watchdog();
592 	} while (time_before(jiffies, timeo));
593 };
594 
595 /**
596  * nand_command - [DEFAULT] Send command to NAND device
597  * @mtd: MTD device structure
598  * @command: the command to be sent
599  * @column: the column address for this command, -1 if none
600  * @page_addr: the page address for this command, -1 if none
601  *
602  * Send command to NAND device. This function is used for small page devices
603  * (512 Bytes per page).
604  */
nand_command(struct mtd_info * mtd,unsigned int command,int column,int page_addr)605 static void nand_command(struct mtd_info *mtd, unsigned int command,
606 			 int column, int page_addr)
607 {
608 	register struct nand_chip *chip = mtd->priv;
609 	int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
610 
611 	/* Write out the command to the device */
612 	if (command == NAND_CMD_SEQIN) {
613 		int readcmd;
614 
615 		if (column >= mtd->writesize) {
616 			/* OOB area */
617 			column -= mtd->writesize;
618 			readcmd = NAND_CMD_READOOB;
619 		} else if (column < 256) {
620 			/* First 256 bytes --> READ0 */
621 			readcmd = NAND_CMD_READ0;
622 		} else {
623 			column -= 256;
624 			readcmd = NAND_CMD_READ1;
625 		}
626 		chip->cmd_ctrl(mtd, readcmd, ctrl);
627 		ctrl &= ~NAND_CTRL_CHANGE;
628 	}
629 	if (command != NAND_CMD_NONE)
630 		chip->cmd_ctrl(mtd, command, ctrl);
631 
632 	/* Address cycle, when necessary */
633 	ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE;
634 	/* Serially input address */
635 	if (column != -1) {
636 		/* Adjust columns for 16 bit buswidth */
637 		if (chip->options & NAND_BUSWIDTH_16 &&
638 				!nand_opcode_8bits(command))
639 			column >>= 1;
640 		chip->cmd_ctrl(mtd, column, ctrl);
641 		ctrl &= ~NAND_CTRL_CHANGE;
642 	}
643 	if (page_addr != -1) {
644 		chip->cmd_ctrl(mtd, page_addr, ctrl);
645 		ctrl &= ~NAND_CTRL_CHANGE;
646 		chip->cmd_ctrl(mtd, page_addr >> 8, ctrl);
647 		/* One more address cycle for devices > 32MiB */
648 		if (chip->chipsize > (32 << 20))
649 			chip->cmd_ctrl(mtd, page_addr >> 16, ctrl);
650 	}
651 	chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
652 
653 	/*
654 	 * Program and erase have their own busy handlers status and sequential
655 	 * in needs no delay
656 	 */
657 	switch (command) {
658 
659 	case NAND_CMD_NONE:
660 	case NAND_CMD_PAGEPROG:
661 	case NAND_CMD_ERASE1:
662 	case NAND_CMD_ERASE2:
663 	case NAND_CMD_SEQIN:
664 	case NAND_CMD_STATUS:
665 		return;
666 
667 	case NAND_CMD_RESET:
668 		if (chip->dev_ready)
669 			break;
670 		udelay(chip->chip_delay);
671 		chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
672 			       NAND_CTRL_CLE | NAND_CTRL_CHANGE);
673 		chip->cmd_ctrl(mtd,
674 			       NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
675 		/* EZ-NAND can take upto 250ms as per ONFi v4.0 */
676 		nand_wait_status_ready(mtd, 250);
677 		return;
678 
679 		/* This applies to read commands */
680 	default:
681 		/*
682 		 * If we don't have access to the busy pin, we apply the given
683 		 * command delay
684 		 */
685 		if (!chip->dev_ready) {
686 			udelay(chip->chip_delay);
687 			return;
688 		}
689 	}
690 	/*
691 	 * Apply this short delay always to ensure that we do wait tWB in
692 	 * any case on any machine.
693 	 */
694 	ndelay(100);
695 
696 	nand_wait_ready(mtd);
697 }
698 
699 /**
700  * nand_command_lp - [DEFAULT] Send command to NAND large page device
701  * @mtd: MTD device structure
702  * @command: the command to be sent
703  * @column: the column address for this command, -1 if none
704  * @page_addr: the page address for this command, -1 if none
705  *
706  * Send command to NAND device. This is the version for the new large page
707  * devices. We don't have the separate regions as we have in the small page
708  * devices. We must emulate NAND_CMD_READOOB to keep the code compatible.
709  */
nand_command_lp(struct mtd_info * mtd,unsigned int command,int column,int page_addr)710 static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
711 			    int column, int page_addr)
712 {
713 	register struct nand_chip *chip = mtd->priv;
714 
715 	/* Emulate NAND_CMD_READOOB */
716 	if (command == NAND_CMD_READOOB) {
717 		column += mtd->writesize;
718 		command = NAND_CMD_READ0;
719 	}
720 
721 	/* Command latch cycle */
722 	if (command != NAND_CMD_NONE)
723 		chip->cmd_ctrl(mtd, command,
724 			       NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
725 
726 	if (column != -1 || page_addr != -1) {
727 		int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
728 
729 		/* Serially input address */
730 		if (column != -1) {
731 			/* Adjust columns for 16 bit buswidth */
732 			if (chip->options & NAND_BUSWIDTH_16 &&
733 					!nand_opcode_8bits(command))
734 				column >>= 1;
735 			chip->cmd_ctrl(mtd, column, ctrl);
736 			ctrl &= ~NAND_CTRL_CHANGE;
737 			chip->cmd_ctrl(mtd, column >> 8, ctrl);
738 		}
739 		if (page_addr != -1) {
740 			chip->cmd_ctrl(mtd, page_addr, ctrl);
741 			chip->cmd_ctrl(mtd, page_addr >> 8,
742 				       NAND_NCE | NAND_ALE);
743 			/* One more address cycle for devices > 128MiB */
744 			if (chip->chipsize > (128 << 20))
745 				chip->cmd_ctrl(mtd, page_addr >> 16,
746 					       NAND_NCE | NAND_ALE);
747 		}
748 	}
749 	chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
750 
751 	/*
752 	 * Program and erase have their own busy handlers status, sequential
753 	 * in and status need no delay.
754 	 */
755 	switch (command) {
756 
757 	case NAND_CMD_NONE:
758 	case NAND_CMD_CACHEDPROG:
759 	case NAND_CMD_PAGEPROG:
760 	case NAND_CMD_ERASE1:
761 	case NAND_CMD_ERASE2:
762 	case NAND_CMD_SEQIN:
763 	case NAND_CMD_RNDIN:
764 	case NAND_CMD_STATUS:
765 		return;
766 
767 	case NAND_CMD_RESET:
768 		if (chip->dev_ready)
769 			break;
770 		udelay(chip->chip_delay);
771 		chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
772 			       NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
773 		chip->cmd_ctrl(mtd, NAND_CMD_NONE,
774 			       NAND_NCE | NAND_CTRL_CHANGE);
775 		/* EZ-NAND can take upto 250ms as per ONFi v4.0 */
776 		nand_wait_status_ready(mtd, 250);
777 		return;
778 
779 	case NAND_CMD_RNDOUT:
780 		/* No ready / busy check necessary */
781 		chip->cmd_ctrl(mtd, NAND_CMD_RNDOUTSTART,
782 			       NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
783 		chip->cmd_ctrl(mtd, NAND_CMD_NONE,
784 			       NAND_NCE | NAND_CTRL_CHANGE);
785 		return;
786 
787 	case NAND_CMD_READ0:
788 		chip->cmd_ctrl(mtd, NAND_CMD_READSTART,
789 			       NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
790 		chip->cmd_ctrl(mtd, NAND_CMD_NONE,
791 			       NAND_NCE | NAND_CTRL_CHANGE);
792 
793 		/* This applies to read commands */
794 	default:
795 		/*
796 		 * If we don't have access to the busy pin, we apply the given
797 		 * command delay.
798 		 */
799 		if (!chip->dev_ready) {
800 			udelay(chip->chip_delay);
801 			return;
802 		}
803 	}
804 
805 	/*
806 	 * Apply this short delay always to ensure that we do wait tWB in
807 	 * any case on any machine.
808 	 */
809 	ndelay(100);
810 
811 	nand_wait_ready(mtd);
812 }
813 
814 /**
815  * panic_nand_get_device - [GENERIC] Get chip for selected access
816  * @chip: the nand chip descriptor
817  * @mtd: MTD device structure
818  * @new_state: the state which is requested
819  *
820  * Used when in panic, no locks are taken.
821  */
panic_nand_get_device(struct nand_chip * chip,struct mtd_info * mtd,int new_state)822 static void panic_nand_get_device(struct nand_chip *chip,
823 		      struct mtd_info *mtd, int new_state)
824 {
825 	/* Hardware controller shared among independent devices */
826 	chip->controller->active = chip;
827 	chip->state = new_state;
828 }
829 
830 /**
831  * nand_get_device - [GENERIC] Get chip for selected access
832  * @mtd: MTD device structure
833  * @new_state: the state which is requested
834  *
835  * Get the device and lock it for exclusive access
836  */
837 static int
nand_get_device(struct mtd_info * mtd,int new_state)838 nand_get_device(struct mtd_info *mtd, int new_state)
839 {
840 	struct nand_chip *chip = mtd->priv;
841 	spinlock_t *lock = &chip->controller->lock;
842 	wait_queue_head_t *wq = &chip->controller->wq;
843 	DECLARE_WAITQUEUE(wait, current);
844 retry:
845 	spin_lock(lock);
846 
847 	/* Hardware controller shared among independent devices */
848 	if (!chip->controller->active)
849 		chip->controller->active = chip;
850 
851 	if (chip->controller->active == chip && chip->state == FL_READY) {
852 		chip->state = new_state;
853 		spin_unlock(lock);
854 		return 0;
855 	}
856 	if (new_state == FL_PM_SUSPENDED) {
857 		if (chip->controller->active->state == FL_PM_SUSPENDED) {
858 			chip->state = FL_PM_SUSPENDED;
859 			spin_unlock(lock);
860 			return 0;
861 		}
862 	}
863 	set_current_state(TASK_UNINTERRUPTIBLE);
864 	add_wait_queue(wq, &wait);
865 	spin_unlock(lock);
866 	schedule();
867 	remove_wait_queue(wq, &wait);
868 	goto retry;
869 }
870 
871 /**
872  * panic_nand_wait - [GENERIC] wait until the command is done
873  * @mtd: MTD device structure
874  * @chip: NAND chip structure
875  * @timeo: timeout
876  *
877  * Wait for command done. This is a helper function for nand_wait used when
878  * we are in interrupt context. May happen when in panic and trying to write
879  * an oops through mtdoops.
880  */
panic_nand_wait(struct mtd_info * mtd,struct nand_chip * chip,unsigned long timeo)881 static void panic_nand_wait(struct mtd_info *mtd, struct nand_chip *chip,
882 			    unsigned long timeo)
883 {
884 	int i;
885 	for (i = 0; i < timeo; i++) {
886 		if (chip->dev_ready) {
887 			if (chip->dev_ready(mtd))
888 				break;
889 		} else {
890 			if (chip->read_byte(mtd) & NAND_STATUS_READY)
891 				break;
892 		}
893 		mdelay(1);
894 	}
895 }
896 
897 /**
898  * nand_wait - [DEFAULT] wait until the command is done
899  * @mtd: MTD device structure
900  * @chip: NAND chip structure
901  *
902  * Wait for command done. This applies to erase and program only.
903  */
nand_wait(struct mtd_info * mtd,struct nand_chip * chip)904 static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
905 {
906 
907 	int status;
908 	unsigned long timeo = 400;
909 
910 	led_trigger_event(nand_led_trigger, LED_FULL);
911 
912 	/*
913 	 * Apply this short delay always to ensure that we do wait tWB in any
914 	 * case on any machine.
915 	 */
916 	ndelay(100);
917 
918 	chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
919 
920 	if (in_interrupt() || oops_in_progress)
921 		panic_nand_wait(mtd, chip, timeo);
922 	else {
923 		timeo = jiffies + msecs_to_jiffies(timeo);
924 		do {
925 			if (chip->dev_ready) {
926 				if (chip->dev_ready(mtd))
927 					break;
928 			} else {
929 				if (chip->read_byte(mtd) & NAND_STATUS_READY)
930 					break;
931 			}
932 			cond_resched();
933 		} while (time_before(jiffies, timeo));
934 	}
935 	led_trigger_event(nand_led_trigger, LED_OFF);
936 
937 	status = (int)chip->read_byte(mtd);
938 	/* This can happen if in case of timeout or buggy dev_ready */
939 	WARN_ON(!(status & NAND_STATUS_READY));
940 	return status;
941 }
942 
943 /**
944  * __nand_unlock - [REPLACEABLE] unlocks specified locked blocks
945  * @mtd: mtd info
946  * @ofs: offset to start unlock from
947  * @len: length to unlock
948  * @invert: when = 0, unlock the range of blocks within the lower and
949  *                    upper boundary address
950  *          when = 1, unlock the range of blocks outside the boundaries
951  *                    of the lower and upper boundary address
952  *
953  * Returs unlock status.
954  */
__nand_unlock(struct mtd_info * mtd,loff_t ofs,uint64_t len,int invert)955 static int __nand_unlock(struct mtd_info *mtd, loff_t ofs,
956 					uint64_t len, int invert)
957 {
958 	int ret = 0;
959 	int status, page;
960 	struct nand_chip *chip = mtd->priv;
961 
962 	/* Submit address of first page to unlock */
963 	page = ofs >> chip->page_shift;
964 	chip->cmdfunc(mtd, NAND_CMD_UNLOCK1, -1, page & chip->pagemask);
965 
966 	/* Submit address of last page to unlock */
967 	page = (ofs + len) >> chip->page_shift;
968 	chip->cmdfunc(mtd, NAND_CMD_UNLOCK2, -1,
969 				(page | invert) & chip->pagemask);
970 
971 	/* Call wait ready function */
972 	status = chip->waitfunc(mtd, chip);
973 	/* See if device thinks it succeeded */
974 	if (status & NAND_STATUS_FAIL) {
975 		pr_debug("%s: error status = 0x%08x\n",
976 					__func__, status);
977 		ret = -EIO;
978 	}
979 
980 	return ret;
981 }
982 
983 /**
984  * nand_unlock - [REPLACEABLE] unlocks specified locked blocks
985  * @mtd: mtd info
986  * @ofs: offset to start unlock from
987  * @len: length to unlock
988  *
989  * Returns unlock status.
990  */
nand_unlock(struct mtd_info * mtd,loff_t ofs,uint64_t len)991 int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
992 {
993 	int ret = 0;
994 	int chipnr;
995 	struct nand_chip *chip = mtd->priv;
996 
997 	pr_debug("%s: start = 0x%012llx, len = %llu\n",
998 			__func__, (unsigned long long)ofs, len);
999 
1000 	if (check_offs_len(mtd, ofs, len))
1001 		return -EINVAL;
1002 
1003 	/* Align to last block address if size addresses end of the device */
1004 	if (ofs + len == mtd->size)
1005 		len -= mtd->erasesize;
1006 
1007 	nand_get_device(mtd, FL_UNLOCKING);
1008 
1009 	/* Shift to get chip number */
1010 	chipnr = ofs >> chip->chip_shift;
1011 
1012 	chip->select_chip(mtd, chipnr);
1013 
1014 	/*
1015 	 * Reset the chip.
1016 	 * If we want to check the WP through READ STATUS and check the bit 7
1017 	 * we must reset the chip
1018 	 * some operation can also clear the bit 7 of status register
1019 	 * eg. erase/program a locked block
1020 	 */
1021 	chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
1022 
1023 	/* Check, if it is write protected */
1024 	if (nand_check_wp(mtd)) {
1025 		pr_debug("%s: device is write protected!\n",
1026 					__func__);
1027 		ret = -EIO;
1028 		goto out;
1029 	}
1030 
1031 	ret = __nand_unlock(mtd, ofs, len, 0);
1032 
1033 out:
1034 	chip->select_chip(mtd, -1);
1035 	nand_release_device(mtd);
1036 
1037 	return ret;
1038 }
1039 EXPORT_SYMBOL(nand_unlock);
1040 
1041 /**
1042  * nand_lock - [REPLACEABLE] locks all blocks present in the device
1043  * @mtd: mtd info
1044  * @ofs: offset to start unlock from
1045  * @len: length to unlock
1046  *
1047  * This feature is not supported in many NAND parts. 'Micron' NAND parts do
1048  * have this feature, but it allows only to lock all blocks, not for specified
1049  * range for block. Implementing 'lock' feature by making use of 'unlock', for
1050  * now.
1051  *
1052  * Returns lock status.
1053  */
nand_lock(struct mtd_info * mtd,loff_t ofs,uint64_t len)1054 int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
1055 {
1056 	int ret = 0;
1057 	int chipnr, status, page;
1058 	struct nand_chip *chip = mtd->priv;
1059 
1060 	pr_debug("%s: start = 0x%012llx, len = %llu\n",
1061 			__func__, (unsigned long long)ofs, len);
1062 
1063 	if (check_offs_len(mtd, ofs, len))
1064 		return -EINVAL;
1065 
1066 	nand_get_device(mtd, FL_LOCKING);
1067 
1068 	/* Shift to get chip number */
1069 	chipnr = ofs >> chip->chip_shift;
1070 
1071 	chip->select_chip(mtd, chipnr);
1072 
1073 	/*
1074 	 * Reset the chip.
1075 	 * If we want to check the WP through READ STATUS and check the bit 7
1076 	 * we must reset the chip
1077 	 * some operation can also clear the bit 7 of status register
1078 	 * eg. erase/program a locked block
1079 	 */
1080 	chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
1081 
1082 	/* Check, if it is write protected */
1083 	if (nand_check_wp(mtd)) {
1084 		pr_debug("%s: device is write protected!\n",
1085 					__func__);
1086 		status = MTD_ERASE_FAILED;
1087 		ret = -EIO;
1088 		goto out;
1089 	}
1090 
1091 	/* Submit address of first page to lock */
1092 	page = ofs >> chip->page_shift;
1093 	chip->cmdfunc(mtd, NAND_CMD_LOCK, -1, page & chip->pagemask);
1094 
1095 	/* Call wait ready function */
1096 	status = chip->waitfunc(mtd, chip);
1097 	/* See if device thinks it succeeded */
1098 	if (status & NAND_STATUS_FAIL) {
1099 		pr_debug("%s: error status = 0x%08x\n",
1100 					__func__, status);
1101 		ret = -EIO;
1102 		goto out;
1103 	}
1104 
1105 	ret = __nand_unlock(mtd, ofs, len, 0x1);
1106 
1107 out:
1108 	chip->select_chip(mtd, -1);
1109 	nand_release_device(mtd);
1110 
1111 	return ret;
1112 }
1113 EXPORT_SYMBOL(nand_lock);
1114 
1115 /**
1116  * nand_check_erased_buf - check if a buffer contains (almost) only 0xff data
1117  * @buf: buffer to test
1118  * @len: buffer length
1119  * @bitflips_threshold: maximum number of bitflips
1120  *
1121  * Check if a buffer contains only 0xff, which means the underlying region
1122  * has been erased and is ready to be programmed.
1123  * The bitflips_threshold specify the maximum number of bitflips before
1124  * considering the region is not erased.
1125  * Note: The logic of this function has been extracted from the memweight
1126  * implementation, except that nand_check_erased_buf function exit before
1127  * testing the whole buffer if the number of bitflips exceed the
1128  * bitflips_threshold value.
1129  *
1130  * Returns a positive number of bitflips less than or equal to
1131  * bitflips_threshold, or -ERROR_CODE for bitflips in excess of the
1132  * threshold.
1133  */
nand_check_erased_buf(void * buf,int len,int bitflips_threshold)1134 static int nand_check_erased_buf(void *buf, int len, int bitflips_threshold)
1135 {
1136 	const unsigned char *bitmap = buf;
1137 	int bitflips = 0;
1138 	int weight;
1139 
1140 	for (; len && ((uintptr_t)bitmap) % sizeof(long);
1141 	     len--, bitmap++) {
1142 		weight = hweight8(*bitmap);
1143 		bitflips += BITS_PER_BYTE - weight;
1144 		if (unlikely(bitflips > bitflips_threshold))
1145 			return -EBADMSG;
1146 	}
1147 
1148 	for (; len >= sizeof(long);
1149 	     len -= sizeof(long), bitmap += sizeof(long)) {
1150 		weight = hweight_long(*((unsigned long *)bitmap));
1151 		bitflips += BITS_PER_LONG - weight;
1152 		if (unlikely(bitflips > bitflips_threshold))
1153 			return -EBADMSG;
1154 	}
1155 
1156 	for (; len > 0; len--, bitmap++) {
1157 		weight = hweight8(*bitmap);
1158 		bitflips += BITS_PER_BYTE - weight;
1159 		if (unlikely(bitflips > bitflips_threshold))
1160 			return -EBADMSG;
1161 	}
1162 
1163 	return bitflips;
1164 }
1165 
1166 /**
1167  * nand_check_erased_ecc_chunk - check if an ECC chunk contains (almost) only
1168  *				 0xff data
1169  * @data: data buffer to test
1170  * @datalen: data length
1171  * @ecc: ECC buffer
1172  * @ecclen: ECC length
1173  * @extraoob: extra OOB buffer
1174  * @extraooblen: extra OOB length
1175  * @bitflips_threshold: maximum number of bitflips
1176  *
1177  * Check if a data buffer and its associated ECC and OOB data contains only
1178  * 0xff pattern, which means the underlying region has been erased and is
1179  * ready to be programmed.
1180  * The bitflips_threshold specify the maximum number of bitflips before
1181  * considering the region as not erased.
1182  *
1183  * Note:
1184  * 1/ ECC algorithms are working on pre-defined block sizes which are usually
1185  *    different from the NAND page size. When fixing bitflips, ECC engines will
1186  *    report the number of errors per chunk, and the NAND core infrastructure
1187  *    expect you to return the maximum number of bitflips for the whole page.
1188  *    This is why you should always use this function on a single chunk and
1189  *    not on the whole page. After checking each chunk you should update your
1190  *    max_bitflips value accordingly.
1191  * 2/ When checking for bitflips in erased pages you should not only check
1192  *    the payload data but also their associated ECC data, because a user might
1193  *    have programmed almost all bits to 1 but a few. In this case, we
1194  *    shouldn't consider the chunk as erased, and checking ECC bytes prevent
1195  *    this case.
1196  * 3/ The extraoob argument is optional, and should be used if some of your OOB
1197  *    data are protected by the ECC engine.
1198  *    It could also be used if you support subpages and want to attach some
1199  *    extra OOB data to an ECC chunk.
1200  *
1201  * Returns a positive number of bitflips less than or equal to
1202  * bitflips_threshold, or -ERROR_CODE for bitflips in excess of the
1203  * threshold. In case of success, the passed buffers are filled with 0xff.
1204  */
nand_check_erased_ecc_chunk(void * data,int datalen,void * ecc,int ecclen,void * extraoob,int extraooblen,int bitflips_threshold)1205 int nand_check_erased_ecc_chunk(void *data, int datalen,
1206 				void *ecc, int ecclen,
1207 				void *extraoob, int extraooblen,
1208 				int bitflips_threshold)
1209 {
1210 	int data_bitflips = 0, ecc_bitflips = 0, extraoob_bitflips = 0;
1211 
1212 	data_bitflips = nand_check_erased_buf(data, datalen,
1213 					      bitflips_threshold);
1214 	if (data_bitflips < 0)
1215 		return data_bitflips;
1216 
1217 	bitflips_threshold -= data_bitflips;
1218 
1219 	ecc_bitflips = nand_check_erased_buf(ecc, ecclen, bitflips_threshold);
1220 	if (ecc_bitflips < 0)
1221 		return ecc_bitflips;
1222 
1223 	bitflips_threshold -= ecc_bitflips;
1224 
1225 	extraoob_bitflips = nand_check_erased_buf(extraoob, extraooblen,
1226 						  bitflips_threshold);
1227 	if (extraoob_bitflips < 0)
1228 		return extraoob_bitflips;
1229 
1230 	if (data_bitflips)
1231 		memset(data, 0xff, datalen);
1232 
1233 	if (ecc_bitflips)
1234 		memset(ecc, 0xff, ecclen);
1235 
1236 	if (extraoob_bitflips)
1237 		memset(extraoob, 0xff, extraooblen);
1238 
1239 	return data_bitflips + ecc_bitflips + extraoob_bitflips;
1240 }
1241 EXPORT_SYMBOL(nand_check_erased_ecc_chunk);
1242 
1243 /**
1244  * nand_read_page_raw - [INTERN] read raw page data without ecc
1245  * @mtd: mtd info structure
1246  * @chip: nand chip info structure
1247  * @buf: buffer to store read data
1248  * @oob_required: caller requires OOB data read to chip->oob_poi
1249  * @page: page number to read
1250  *
1251  * Not for syndrome calculating ECC controllers, which use a special oob layout.
1252  */
nand_read_page_raw(struct mtd_info * mtd,struct nand_chip * chip,uint8_t * buf,int oob_required,int page)1253 static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1254 			      uint8_t *buf, int oob_required, int page)
1255 {
1256 	chip->read_buf(mtd, buf, mtd->writesize);
1257 	if (oob_required)
1258 		chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1259 	return 0;
1260 }
1261 
1262 /**
1263  * nand_read_page_raw_syndrome - [INTERN] read raw page data without ecc
1264  * @mtd: mtd info structure
1265  * @chip: nand chip info structure
1266  * @buf: buffer to store read data
1267  * @oob_required: caller requires OOB data read to chip->oob_poi
1268  * @page: page number to read
1269  *
1270  * We need a special oob layout and handling even when OOB isn't used.
1271  */
nand_read_page_raw_syndrome(struct mtd_info * mtd,struct nand_chip * chip,uint8_t * buf,int oob_required,int page)1272 static int nand_read_page_raw_syndrome(struct mtd_info *mtd,
1273 				       struct nand_chip *chip, uint8_t *buf,
1274 				       int oob_required, int page)
1275 {
1276 	int eccsize = chip->ecc.size;
1277 	int eccbytes = chip->ecc.bytes;
1278 	uint8_t *oob = chip->oob_poi;
1279 	int steps, size;
1280 
1281 	for (steps = chip->ecc.steps; steps > 0; steps--) {
1282 		chip->read_buf(mtd, buf, eccsize);
1283 		buf += eccsize;
1284 
1285 		if (chip->ecc.prepad) {
1286 			chip->read_buf(mtd, oob, chip->ecc.prepad);
1287 			oob += chip->ecc.prepad;
1288 		}
1289 
1290 		chip->read_buf(mtd, oob, eccbytes);
1291 		oob += eccbytes;
1292 
1293 		if (chip->ecc.postpad) {
1294 			chip->read_buf(mtd, oob, chip->ecc.postpad);
1295 			oob += chip->ecc.postpad;
1296 		}
1297 	}
1298 
1299 	size = mtd->oobsize - (oob - chip->oob_poi);
1300 	if (size)
1301 		chip->read_buf(mtd, oob, size);
1302 
1303 	return 0;
1304 }
1305 
1306 /**
1307  * nand_read_page_swecc - [REPLACEABLE] software ECC based page read function
1308  * @mtd: mtd info structure
1309  * @chip: nand chip info structure
1310  * @buf: buffer to store read data
1311  * @oob_required: caller requires OOB data read to chip->oob_poi
1312  * @page: page number to read
1313  */
nand_read_page_swecc(struct mtd_info * mtd,struct nand_chip * chip,uint8_t * buf,int oob_required,int page)1314 static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
1315 				uint8_t *buf, int oob_required, int page)
1316 {
1317 	int i, eccsize = chip->ecc.size;
1318 	int eccbytes = chip->ecc.bytes;
1319 	int eccsteps = chip->ecc.steps;
1320 	uint8_t *p = buf;
1321 	uint8_t *ecc_calc = chip->buffers->ecccalc;
1322 	uint8_t *ecc_code = chip->buffers->ecccode;
1323 	uint32_t *eccpos = chip->ecc.layout->eccpos;
1324 	unsigned int max_bitflips = 0;
1325 
1326 	chip->ecc.read_page_raw(mtd, chip, buf, 1, page);
1327 
1328 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
1329 		chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1330 
1331 	for (i = 0; i < chip->ecc.total; i++)
1332 		ecc_code[i] = chip->oob_poi[eccpos[i]];
1333 
1334 	eccsteps = chip->ecc.steps;
1335 	p = buf;
1336 
1337 	for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1338 		int stat;
1339 
1340 		stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
1341 		if (stat < 0) {
1342 			mtd->ecc_stats.failed++;
1343 		} else {
1344 			mtd->ecc_stats.corrected += stat;
1345 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1346 		}
1347 	}
1348 	return max_bitflips;
1349 }
1350 
1351 /**
1352  * nand_read_subpage - [REPLACEABLE] ECC based sub-page read function
1353  * @mtd: mtd info structure
1354  * @chip: nand chip info structure
1355  * @data_offs: offset of requested data within the page
1356  * @readlen: data length
1357  * @bufpoi: buffer to store read data
1358  * @page: page number to read
1359  */
nand_read_subpage(struct mtd_info * mtd,struct nand_chip * chip,uint32_t data_offs,uint32_t readlen,uint8_t * bufpoi,int page)1360 static int nand_read_subpage(struct mtd_info *mtd, struct nand_chip *chip,
1361 			uint32_t data_offs, uint32_t readlen, uint8_t *bufpoi,
1362 			int page)
1363 {
1364 	int start_step, end_step, num_steps;
1365 	uint32_t *eccpos = chip->ecc.layout->eccpos;
1366 	uint8_t *p;
1367 	int data_col_addr, i, gaps = 0;
1368 	int datafrag_len, eccfrag_len, aligned_len, aligned_pos;
1369 	int busw = (chip->options & NAND_BUSWIDTH_16) ? 2 : 1;
1370 	int index;
1371 	unsigned int max_bitflips = 0;
1372 
1373 	/* Column address within the page aligned to ECC size (256bytes) */
1374 	start_step = data_offs / chip->ecc.size;
1375 	end_step = (data_offs + readlen - 1) / chip->ecc.size;
1376 	num_steps = end_step - start_step + 1;
1377 	index = start_step * chip->ecc.bytes;
1378 
1379 	/* Data size aligned to ECC ecc.size */
1380 	datafrag_len = num_steps * chip->ecc.size;
1381 	eccfrag_len = num_steps * chip->ecc.bytes;
1382 
1383 	data_col_addr = start_step * chip->ecc.size;
1384 	/* If we read not a page aligned data */
1385 	if (data_col_addr != 0)
1386 		chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_col_addr, -1);
1387 
1388 	p = bufpoi + data_col_addr;
1389 	chip->read_buf(mtd, p, datafrag_len);
1390 
1391 	/* Calculate ECC */
1392 	for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size)
1393 		chip->ecc.calculate(mtd, p, &chip->buffers->ecccalc[i]);
1394 
1395 	/*
1396 	 * The performance is faster if we position offsets according to
1397 	 * ecc.pos. Let's make sure that there are no gaps in ECC positions.
1398 	 */
1399 	for (i = 0; i < eccfrag_len - 1; i++) {
1400 		if (eccpos[i + index] + 1 != eccpos[i + index + 1]) {
1401 			gaps = 1;
1402 			break;
1403 		}
1404 	}
1405 	if (gaps) {
1406 		chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
1407 		chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1408 	} else {
1409 		/*
1410 		 * Send the command to read the particular ECC bytes take care
1411 		 * about buswidth alignment in read_buf.
1412 		 */
1413 		aligned_pos = eccpos[index] & ~(busw - 1);
1414 		aligned_len = eccfrag_len;
1415 		if (eccpos[index] & (busw - 1))
1416 			aligned_len++;
1417 		if (eccpos[index + (num_steps * chip->ecc.bytes)] & (busw - 1))
1418 			aligned_len++;
1419 
1420 		chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
1421 					mtd->writesize + aligned_pos, -1);
1422 		chip->read_buf(mtd, &chip->oob_poi[aligned_pos], aligned_len);
1423 	}
1424 
1425 	for (i = 0; i < eccfrag_len; i++)
1426 		chip->buffers->ecccode[i] = chip->oob_poi[eccpos[i + index]];
1427 
1428 	p = bufpoi + data_col_addr;
1429 	for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size) {
1430 		int stat;
1431 
1432 		stat = chip->ecc.correct(mtd, p,
1433 			&chip->buffers->ecccode[i], &chip->buffers->ecccalc[i]);
1434 		if (stat < 0) {
1435 			mtd->ecc_stats.failed++;
1436 		} else {
1437 			mtd->ecc_stats.corrected += stat;
1438 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1439 		}
1440 	}
1441 	return max_bitflips;
1442 }
1443 
1444 /**
1445  * nand_read_page_hwecc - [REPLACEABLE] hardware ECC based page read function
1446  * @mtd: mtd info structure
1447  * @chip: nand chip info structure
1448  * @buf: buffer to store read data
1449  * @oob_required: caller requires OOB data read to chip->oob_poi
1450  * @page: page number to read
1451  *
1452  * Not for syndrome calculating ECC controllers which need a special oob layout.
1453  */
nand_read_page_hwecc(struct mtd_info * mtd,struct nand_chip * chip,uint8_t * buf,int oob_required,int page)1454 static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
1455 				uint8_t *buf, int oob_required, int page)
1456 {
1457 	int i, eccsize = chip->ecc.size;
1458 	int eccbytes = chip->ecc.bytes;
1459 	int eccsteps = chip->ecc.steps;
1460 	uint8_t *p = buf;
1461 	uint8_t *ecc_calc = chip->buffers->ecccalc;
1462 	uint8_t *ecc_code = chip->buffers->ecccode;
1463 	uint32_t *eccpos = chip->ecc.layout->eccpos;
1464 	unsigned int max_bitflips = 0;
1465 
1466 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1467 		chip->ecc.hwctl(mtd, NAND_ECC_READ);
1468 		chip->read_buf(mtd, p, eccsize);
1469 		chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1470 	}
1471 	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1472 
1473 	for (i = 0; i < chip->ecc.total; i++)
1474 		ecc_code[i] = chip->oob_poi[eccpos[i]];
1475 
1476 	eccsteps = chip->ecc.steps;
1477 	p = buf;
1478 
1479 	for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1480 		int stat;
1481 
1482 		stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
1483 		if (stat < 0) {
1484 			mtd->ecc_stats.failed++;
1485 		} else {
1486 			mtd->ecc_stats.corrected += stat;
1487 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1488 		}
1489 	}
1490 	return max_bitflips;
1491 }
1492 
1493 /**
1494  * nand_read_page_hwecc_oob_first - [REPLACEABLE] hw ecc, read oob first
1495  * @mtd: mtd info structure
1496  * @chip: nand chip info structure
1497  * @buf: buffer to store read data
1498  * @oob_required: caller requires OOB data read to chip->oob_poi
1499  * @page: page number to read
1500  *
1501  * Hardware ECC for large page chips, require OOB to be read first. For this
1502  * ECC mode, the write_page method is re-used from ECC_HW. These methods
1503  * read/write ECC from the OOB area, unlike the ECC_HW_SYNDROME support with
1504  * multiple ECC steps, follows the "infix ECC" scheme and reads/writes ECC from
1505  * the data area, by overwriting the NAND manufacturer bad block markings.
1506  */
nand_read_page_hwecc_oob_first(struct mtd_info * mtd,struct nand_chip * chip,uint8_t * buf,int oob_required,int page)1507 static int nand_read_page_hwecc_oob_first(struct mtd_info *mtd,
1508 	struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
1509 {
1510 	int i, eccsize = chip->ecc.size;
1511 	int eccbytes = chip->ecc.bytes;
1512 	int eccsteps = chip->ecc.steps;
1513 	uint8_t *p = buf;
1514 	uint8_t *ecc_code = chip->buffers->ecccode;
1515 	uint32_t *eccpos = chip->ecc.layout->eccpos;
1516 	uint8_t *ecc_calc = chip->buffers->ecccalc;
1517 	unsigned int max_bitflips = 0;
1518 
1519 	/* Read the OOB area first */
1520 	chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1521 	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1522 	chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
1523 
1524 	for (i = 0; i < chip->ecc.total; i++)
1525 		ecc_code[i] = chip->oob_poi[eccpos[i]];
1526 
1527 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1528 		int stat;
1529 
1530 		chip->ecc.hwctl(mtd, NAND_ECC_READ);
1531 		chip->read_buf(mtd, p, eccsize);
1532 		chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1533 
1534 		stat = chip->ecc.correct(mtd, p, &ecc_code[i], NULL);
1535 		if (stat < 0) {
1536 			mtd->ecc_stats.failed++;
1537 		} else {
1538 			mtd->ecc_stats.corrected += stat;
1539 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1540 		}
1541 	}
1542 	return max_bitflips;
1543 }
1544 
1545 /**
1546  * nand_read_page_syndrome - [REPLACEABLE] hardware ECC syndrome based page read
1547  * @mtd: mtd info structure
1548  * @chip: nand chip info structure
1549  * @buf: buffer to store read data
1550  * @oob_required: caller requires OOB data read to chip->oob_poi
1551  * @page: page number to read
1552  *
1553  * The hw generator calculates the error syndrome automatically. Therefore we
1554  * need a special oob layout and handling.
1555  */
nand_read_page_syndrome(struct mtd_info * mtd,struct nand_chip * chip,uint8_t * buf,int oob_required,int page)1556 static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1557 				   uint8_t *buf, int oob_required, int page)
1558 {
1559 	int i, eccsize = chip->ecc.size;
1560 	int eccbytes = chip->ecc.bytes;
1561 	int eccsteps = chip->ecc.steps;
1562 	uint8_t *p = buf;
1563 	uint8_t *oob = chip->oob_poi;
1564 	unsigned int max_bitflips = 0;
1565 
1566 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1567 		int stat;
1568 
1569 		chip->ecc.hwctl(mtd, NAND_ECC_READ);
1570 		chip->read_buf(mtd, p, eccsize);
1571 
1572 		if (chip->ecc.prepad) {
1573 			chip->read_buf(mtd, oob, chip->ecc.prepad);
1574 			oob += chip->ecc.prepad;
1575 		}
1576 
1577 		chip->ecc.hwctl(mtd, NAND_ECC_READSYN);
1578 		chip->read_buf(mtd, oob, eccbytes);
1579 		stat = chip->ecc.correct(mtd, p, oob, NULL);
1580 
1581 		if (stat < 0) {
1582 			mtd->ecc_stats.failed++;
1583 		} else {
1584 			mtd->ecc_stats.corrected += stat;
1585 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1586 		}
1587 
1588 		oob += eccbytes;
1589 
1590 		if (chip->ecc.postpad) {
1591 			chip->read_buf(mtd, oob, chip->ecc.postpad);
1592 			oob += chip->ecc.postpad;
1593 		}
1594 	}
1595 
1596 	/* Calculate remaining oob bytes */
1597 	i = mtd->oobsize - (oob - chip->oob_poi);
1598 	if (i)
1599 		chip->read_buf(mtd, oob, i);
1600 
1601 	return max_bitflips;
1602 }
1603 
1604 /**
1605  * nand_transfer_oob - [INTERN] Transfer oob to client buffer
1606  * @chip: nand chip structure
1607  * @oob: oob destination address
1608  * @ops: oob ops structure
1609  * @len: size of oob to transfer
1610  */
nand_transfer_oob(struct nand_chip * chip,uint8_t * oob,struct mtd_oob_ops * ops,size_t len)1611 static uint8_t *nand_transfer_oob(struct nand_chip *chip, uint8_t *oob,
1612 				  struct mtd_oob_ops *ops, size_t len)
1613 {
1614 	switch (ops->mode) {
1615 
1616 	case MTD_OPS_PLACE_OOB:
1617 	case MTD_OPS_RAW:
1618 		memcpy(oob, chip->oob_poi + ops->ooboffs, len);
1619 		return oob + len;
1620 
1621 	case MTD_OPS_AUTO_OOB: {
1622 		struct nand_oobfree *free = chip->ecc.layout->oobfree;
1623 		uint32_t boffs = 0, roffs = ops->ooboffs;
1624 		size_t bytes = 0;
1625 
1626 		for (; free->length && len; free++, len -= bytes) {
1627 			/* Read request not from offset 0? */
1628 			if (unlikely(roffs)) {
1629 				if (roffs >= free->length) {
1630 					roffs -= free->length;
1631 					continue;
1632 				}
1633 				boffs = free->offset + roffs;
1634 				bytes = min_t(size_t, len,
1635 					      (free->length - roffs));
1636 				roffs = 0;
1637 			} else {
1638 				bytes = min_t(size_t, len, free->length);
1639 				boffs = free->offset;
1640 			}
1641 			memcpy(oob, chip->oob_poi + boffs, bytes);
1642 			oob += bytes;
1643 		}
1644 		return oob;
1645 	}
1646 	default:
1647 		BUG();
1648 	}
1649 	return NULL;
1650 }
1651 
1652 /**
1653  * nand_setup_read_retry - [INTERN] Set the READ RETRY mode
1654  * @mtd: MTD device structure
1655  * @retry_mode: the retry mode to use
1656  *
1657  * Some vendors supply a special command to shift the Vt threshold, to be used
1658  * when there are too many bitflips in a page (i.e., ECC error). After setting
1659  * a new threshold, the host should retry reading the page.
1660  */
nand_setup_read_retry(struct mtd_info * mtd,int retry_mode)1661 static int nand_setup_read_retry(struct mtd_info *mtd, int retry_mode)
1662 {
1663 	struct nand_chip *chip = mtd->priv;
1664 
1665 	pr_debug("setting READ RETRY mode %d\n", retry_mode);
1666 
1667 	if (retry_mode >= chip->read_retries)
1668 		return -EINVAL;
1669 
1670 	if (!chip->setup_read_retry)
1671 		return -EOPNOTSUPP;
1672 
1673 	return chip->setup_read_retry(mtd, retry_mode);
1674 }
1675 
1676 /**
1677  * nand_do_read_ops - [INTERN] Read data with ECC
1678  * @mtd: MTD device structure
1679  * @from: offset to read from
1680  * @ops: oob ops structure
1681  *
1682  * Internal function. Called with chip held.
1683  */
nand_do_read_ops(struct mtd_info * mtd,loff_t from,struct mtd_oob_ops * ops)1684 static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
1685 			    struct mtd_oob_ops *ops)
1686 {
1687 	int chipnr, page, realpage, col, bytes, aligned, oob_required;
1688 	struct nand_chip *chip = mtd->priv;
1689 	int ret = 0;
1690 	uint32_t readlen = ops->len;
1691 	uint32_t oobreadlen = ops->ooblen;
1692 	uint32_t max_oobsize = ops->mode == MTD_OPS_AUTO_OOB ?
1693 		mtd->oobavail : mtd->oobsize;
1694 
1695 	uint8_t *bufpoi, *oob, *buf;
1696 	int use_bufpoi;
1697 	unsigned int max_bitflips = 0;
1698 	int retry_mode = 0;
1699 	bool ecc_fail = false;
1700 
1701 	chipnr = (int)(from >> chip->chip_shift);
1702 	chip->select_chip(mtd, chipnr);
1703 
1704 	realpage = (int)(from >> chip->page_shift);
1705 	page = realpage & chip->pagemask;
1706 
1707 	col = (int)(from & (mtd->writesize - 1));
1708 
1709 	buf = ops->datbuf;
1710 	oob = ops->oobbuf;
1711 	oob_required = oob ? 1 : 0;
1712 
1713 	while (1) {
1714 		unsigned int ecc_failures = mtd->ecc_stats.failed;
1715 
1716 		bytes = min(mtd->writesize - col, readlen);
1717 		aligned = (bytes == mtd->writesize);
1718 
1719 		if (!aligned)
1720 			use_bufpoi = 1;
1721 		else if (chip->options & NAND_USE_BOUNCE_BUFFER)
1722 			use_bufpoi = !virt_addr_valid(buf);
1723 		else
1724 			use_bufpoi = 0;
1725 
1726 		/* Is the current page in the buffer? */
1727 		if (realpage != chip->pagebuf || oob) {
1728 			bufpoi = use_bufpoi ? chip->buffers->databuf : buf;
1729 
1730 			if (use_bufpoi && aligned)
1731 				pr_debug("%s: using read bounce buffer for buf@%p\n",
1732 						 __func__, buf);
1733 
1734 read_retry:
1735 			chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
1736 
1737 			/*
1738 			 * Now read the page into the buffer.  Absent an error,
1739 			 * the read methods return max bitflips per ecc step.
1740 			 */
1741 			if (unlikely(ops->mode == MTD_OPS_RAW))
1742 				ret = chip->ecc.read_page_raw(mtd, chip, bufpoi,
1743 							      oob_required,
1744 							      page);
1745 			else if (!aligned && NAND_HAS_SUBPAGE_READ(chip) &&
1746 				 !oob)
1747 				ret = chip->ecc.read_subpage(mtd, chip,
1748 							col, bytes, bufpoi,
1749 							page);
1750 			else
1751 				ret = chip->ecc.read_page(mtd, chip, bufpoi,
1752 							  oob_required, page);
1753 			if (ret < 0) {
1754 				if (use_bufpoi)
1755 					/* Invalidate page cache */
1756 					chip->pagebuf = -1;
1757 				break;
1758 			}
1759 
1760 			max_bitflips = max_t(unsigned int, max_bitflips, ret);
1761 
1762 			/* Transfer not aligned data */
1763 			if (use_bufpoi) {
1764 				if (!NAND_HAS_SUBPAGE_READ(chip) && !oob &&
1765 				    !(mtd->ecc_stats.failed - ecc_failures) &&
1766 				    (ops->mode != MTD_OPS_RAW)) {
1767 					chip->pagebuf = realpage;
1768 					chip->pagebuf_bitflips = ret;
1769 				} else {
1770 					/* Invalidate page cache */
1771 					chip->pagebuf = -1;
1772 				}
1773 				memcpy(buf, chip->buffers->databuf + col, bytes);
1774 			}
1775 
1776 			if (unlikely(oob)) {
1777 				int toread = min(oobreadlen, max_oobsize);
1778 
1779 				if (toread) {
1780 					oob = nand_transfer_oob(chip,
1781 						oob, ops, toread);
1782 					oobreadlen -= toread;
1783 				}
1784 			}
1785 
1786 			if (chip->options & NAND_NEED_READRDY) {
1787 				/* Apply delay or wait for ready/busy pin */
1788 				if (!chip->dev_ready)
1789 					udelay(chip->chip_delay);
1790 				else
1791 					nand_wait_ready(mtd);
1792 			}
1793 
1794 			if (mtd->ecc_stats.failed - ecc_failures) {
1795 				if (retry_mode + 1 < chip->read_retries) {
1796 					retry_mode++;
1797 					ret = nand_setup_read_retry(mtd,
1798 							retry_mode);
1799 					if (ret < 0)
1800 						break;
1801 
1802 					/* Reset failures; retry */
1803 					mtd->ecc_stats.failed = ecc_failures;
1804 					goto read_retry;
1805 				} else {
1806 					/* No more retry modes; real failure */
1807 					ecc_fail = true;
1808 				}
1809 			}
1810 
1811 			buf += bytes;
1812 		} else {
1813 			memcpy(buf, chip->buffers->databuf + col, bytes);
1814 			buf += bytes;
1815 			max_bitflips = max_t(unsigned int, max_bitflips,
1816 					     chip->pagebuf_bitflips);
1817 		}
1818 
1819 		readlen -= bytes;
1820 
1821 		/* Reset to retry mode 0 */
1822 		if (retry_mode) {
1823 			ret = nand_setup_read_retry(mtd, 0);
1824 			if (ret < 0)
1825 				break;
1826 			retry_mode = 0;
1827 		}
1828 
1829 		if (!readlen)
1830 			break;
1831 
1832 		/* For subsequent reads align to page boundary */
1833 		col = 0;
1834 		/* Increment page address */
1835 		realpage++;
1836 
1837 		page = realpage & chip->pagemask;
1838 		/* Check, if we cross a chip boundary */
1839 		if (!page) {
1840 			chipnr++;
1841 			chip->select_chip(mtd, -1);
1842 			chip->select_chip(mtd, chipnr);
1843 		}
1844 	}
1845 	chip->select_chip(mtd, -1);
1846 
1847 	ops->retlen = ops->len - (size_t) readlen;
1848 	if (oob)
1849 		ops->oobretlen = ops->ooblen - oobreadlen;
1850 
1851 	if (ret < 0)
1852 		return ret;
1853 
1854 	if (ecc_fail)
1855 		return -EBADMSG;
1856 
1857 	return max_bitflips;
1858 }
1859 
1860 /**
1861  * nand_read - [MTD Interface] MTD compatibility function for nand_do_read_ecc
1862  * @mtd: MTD device structure
1863  * @from: offset to read from
1864  * @len: number of bytes to read
1865  * @retlen: pointer to variable to store the number of read bytes
1866  * @buf: the databuffer to put data
1867  *
1868  * Get hold of the chip and call nand_do_read.
1869  */
nand_read(struct mtd_info * mtd,loff_t from,size_t len,size_t * retlen,uint8_t * buf)1870 static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
1871 		     size_t *retlen, uint8_t *buf)
1872 {
1873 	struct mtd_oob_ops ops;
1874 	int ret;
1875 
1876 	nand_get_device(mtd, FL_READING);
1877 	memset(&ops, 0, sizeof(ops));
1878 	ops.len = len;
1879 	ops.datbuf = buf;
1880 	ops.mode = MTD_OPS_PLACE_OOB;
1881 	ret = nand_do_read_ops(mtd, from, &ops);
1882 	*retlen = ops.retlen;
1883 	nand_release_device(mtd);
1884 	return ret;
1885 }
1886 
1887 /**
1888  * nand_read_oob_std - [REPLACEABLE] the most common OOB data read function
1889  * @mtd: mtd info structure
1890  * @chip: nand chip info structure
1891  * @page: page number to read
1892  */
nand_read_oob_std(struct mtd_info * mtd,struct nand_chip * chip,int page)1893 static int nand_read_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1894 			     int page)
1895 {
1896 	chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1897 	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1898 	return 0;
1899 }
1900 
1901 /**
1902  * nand_read_oob_syndrome - [REPLACEABLE] OOB data read function for HW ECC
1903  *			    with syndromes
1904  * @mtd: mtd info structure
1905  * @chip: nand chip info structure
1906  * @page: page number to read
1907  */
nand_read_oob_syndrome(struct mtd_info * mtd,struct nand_chip * chip,int page)1908 static int nand_read_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1909 				  int page)
1910 {
1911 	int length = mtd->oobsize;
1912 	int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1913 	int eccsize = chip->ecc.size;
1914 	uint8_t *bufpoi = chip->oob_poi;
1915 	int i, toread, sndrnd = 0, pos;
1916 
1917 	chip->cmdfunc(mtd, NAND_CMD_READ0, chip->ecc.size, page);
1918 	for (i = 0; i < chip->ecc.steps; i++) {
1919 		if (sndrnd) {
1920 			pos = eccsize + i * (eccsize + chunk);
1921 			if (mtd->writesize > 512)
1922 				chip->cmdfunc(mtd, NAND_CMD_RNDOUT, pos, -1);
1923 			else
1924 				chip->cmdfunc(mtd, NAND_CMD_READ0, pos, page);
1925 		} else
1926 			sndrnd = 1;
1927 		toread = min_t(int, length, chunk);
1928 		chip->read_buf(mtd, bufpoi, toread);
1929 		bufpoi += toread;
1930 		length -= toread;
1931 	}
1932 	if (length > 0)
1933 		chip->read_buf(mtd, bufpoi, length);
1934 
1935 	return 0;
1936 }
1937 
1938 /**
1939  * nand_write_oob_std - [REPLACEABLE] the most common OOB data write function
1940  * @mtd: mtd info structure
1941  * @chip: nand chip info structure
1942  * @page: page number to write
1943  */
nand_write_oob_std(struct mtd_info * mtd,struct nand_chip * chip,int page)1944 static int nand_write_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1945 			      int page)
1946 {
1947 	int status = 0;
1948 	const uint8_t *buf = chip->oob_poi;
1949 	int length = mtd->oobsize;
1950 
1951 	chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
1952 	chip->write_buf(mtd, buf, length);
1953 	/* Send command to program the OOB data */
1954 	chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1955 
1956 	status = chip->waitfunc(mtd, chip);
1957 
1958 	return status & NAND_STATUS_FAIL ? -EIO : 0;
1959 }
1960 
1961 /**
1962  * nand_write_oob_syndrome - [REPLACEABLE] OOB data write function for HW ECC
1963  *			     with syndrome - only for large page flash
1964  * @mtd: mtd info structure
1965  * @chip: nand chip info structure
1966  * @page: page number to write
1967  */
nand_write_oob_syndrome(struct mtd_info * mtd,struct nand_chip * chip,int page)1968 static int nand_write_oob_syndrome(struct mtd_info *mtd,
1969 				   struct nand_chip *chip, int page)
1970 {
1971 	int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1972 	int eccsize = chip->ecc.size, length = mtd->oobsize;
1973 	int i, len, pos, status = 0, sndcmd = 0, steps = chip->ecc.steps;
1974 	const uint8_t *bufpoi = chip->oob_poi;
1975 
1976 	/*
1977 	 * data-ecc-data-ecc ... ecc-oob
1978 	 * or
1979 	 * data-pad-ecc-pad-data-pad .... ecc-pad-oob
1980 	 */
1981 	if (!chip->ecc.prepad && !chip->ecc.postpad) {
1982 		pos = steps * (eccsize + chunk);
1983 		steps = 0;
1984 	} else
1985 		pos = eccsize;
1986 
1987 	chip->cmdfunc(mtd, NAND_CMD_SEQIN, pos, page);
1988 	for (i = 0; i < steps; i++) {
1989 		if (sndcmd) {
1990 			if (mtd->writesize <= 512) {
1991 				uint32_t fill = 0xFFFFFFFF;
1992 
1993 				len = eccsize;
1994 				while (len > 0) {
1995 					int num = min_t(int, len, 4);
1996 					chip->write_buf(mtd, (uint8_t *)&fill,
1997 							num);
1998 					len -= num;
1999 				}
2000 			} else {
2001 				pos = eccsize + i * (eccsize + chunk);
2002 				chip->cmdfunc(mtd, NAND_CMD_RNDIN, pos, -1);
2003 			}
2004 		} else
2005 			sndcmd = 1;
2006 		len = min_t(int, length, chunk);
2007 		chip->write_buf(mtd, bufpoi, len);
2008 		bufpoi += len;
2009 		length -= len;
2010 	}
2011 	if (length > 0)
2012 		chip->write_buf(mtd, bufpoi, length);
2013 
2014 	chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
2015 	status = chip->waitfunc(mtd, chip);
2016 
2017 	return status & NAND_STATUS_FAIL ? -EIO : 0;
2018 }
2019 
2020 /**
2021  * nand_do_read_oob - [INTERN] NAND read out-of-band
2022  * @mtd: MTD device structure
2023  * @from: offset to read from
2024  * @ops: oob operations description structure
2025  *
2026  * NAND read out-of-band data from the spare area.
2027  */
nand_do_read_oob(struct mtd_info * mtd,loff_t from,struct mtd_oob_ops * ops)2028 static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
2029 			    struct mtd_oob_ops *ops)
2030 {
2031 	unsigned int max_bitflips = 0;
2032 	int page, realpage, chipnr;
2033 	struct nand_chip *chip = mtd->priv;
2034 	struct mtd_ecc_stats stats;
2035 	int readlen = ops->ooblen;
2036 	int len;
2037 	uint8_t *buf = ops->oobbuf;
2038 	int ret = 0;
2039 
2040 	pr_debug("%s: from = 0x%08Lx, len = %i\n",
2041 			__func__, (unsigned long long)from, readlen);
2042 
2043 	stats = mtd->ecc_stats;
2044 
2045 	if (ops->mode == MTD_OPS_AUTO_OOB)
2046 		len = chip->ecc.layout->oobavail;
2047 	else
2048 		len = mtd->oobsize;
2049 
2050 	if (unlikely(ops->ooboffs >= len)) {
2051 		pr_debug("%s: attempt to start read outside oob\n",
2052 				__func__);
2053 		return -EINVAL;
2054 	}
2055 
2056 	/* Do not allow reads past end of device */
2057 	if (unlikely(from >= mtd->size ||
2058 		     ops->ooboffs + readlen > ((mtd->size >> chip->page_shift) -
2059 					(from >> chip->page_shift)) * len)) {
2060 		pr_debug("%s: attempt to read beyond end of device\n",
2061 				__func__);
2062 		return -EINVAL;
2063 	}
2064 
2065 	chipnr = (int)(from >> chip->chip_shift);
2066 	chip->select_chip(mtd, chipnr);
2067 
2068 	/* Shift to get page */
2069 	realpage = (int)(from >> chip->page_shift);
2070 	page = realpage & chip->pagemask;
2071 
2072 	while (1) {
2073 		if (ops->mode == MTD_OPS_RAW)
2074 			ret = chip->ecc.read_oob_raw(mtd, chip, page);
2075 		else
2076 			ret = chip->ecc.read_oob(mtd, chip, page);
2077 
2078 		if (ret < 0)
2079 			break;
2080 
2081 		len = min(len, readlen);
2082 		buf = nand_transfer_oob(chip, buf, ops, len);
2083 
2084 		if (chip->options & NAND_NEED_READRDY) {
2085 			/* Apply delay or wait for ready/busy pin */
2086 			if (!chip->dev_ready)
2087 				udelay(chip->chip_delay);
2088 			else
2089 				nand_wait_ready(mtd);
2090 		}
2091 
2092 		max_bitflips = max_t(unsigned int, max_bitflips, ret);
2093 
2094 		readlen -= len;
2095 		if (!readlen)
2096 			break;
2097 
2098 		/* Increment page address */
2099 		realpage++;
2100 
2101 		page = realpage & chip->pagemask;
2102 		/* Check, if we cross a chip boundary */
2103 		if (!page) {
2104 			chipnr++;
2105 			chip->select_chip(mtd, -1);
2106 			chip->select_chip(mtd, chipnr);
2107 		}
2108 	}
2109 	chip->select_chip(mtd, -1);
2110 
2111 	ops->oobretlen = ops->ooblen - readlen;
2112 
2113 	if (ret < 0)
2114 		return ret;
2115 
2116 	if (mtd->ecc_stats.failed - stats.failed)
2117 		return -EBADMSG;
2118 
2119 	return max_bitflips;
2120 }
2121 
2122 /**
2123  * nand_read_oob - [MTD Interface] NAND read data and/or out-of-band
2124  * @mtd: MTD device structure
2125  * @from: offset to read from
2126  * @ops: oob operation description structure
2127  *
2128  * NAND read data and/or out-of-band data.
2129  */
nand_read_oob(struct mtd_info * mtd,loff_t from,struct mtd_oob_ops * ops)2130 static int nand_read_oob(struct mtd_info *mtd, loff_t from,
2131 			 struct mtd_oob_ops *ops)
2132 {
2133 	int ret = -ENOTSUPP;
2134 
2135 	ops->retlen = 0;
2136 
2137 	/* Do not allow reads past end of device */
2138 	if (ops->datbuf && (from + ops->len) > mtd->size) {
2139 		pr_debug("%s: attempt to read beyond end of device\n",
2140 				__func__);
2141 		return -EINVAL;
2142 	}
2143 
2144 	nand_get_device(mtd, FL_READING);
2145 
2146 	switch (ops->mode) {
2147 	case MTD_OPS_PLACE_OOB:
2148 	case MTD_OPS_AUTO_OOB:
2149 	case MTD_OPS_RAW:
2150 		break;
2151 
2152 	default:
2153 		goto out;
2154 	}
2155 
2156 	if (!ops->datbuf)
2157 		ret = nand_do_read_oob(mtd, from, ops);
2158 	else
2159 		ret = nand_do_read_ops(mtd, from, ops);
2160 
2161 out:
2162 	nand_release_device(mtd);
2163 	return ret;
2164 }
2165 
2166 
2167 /**
2168  * nand_write_page_raw - [INTERN] raw page write function
2169  * @mtd: mtd info structure
2170  * @chip: nand chip info structure
2171  * @buf: data buffer
2172  * @oob_required: must write chip->oob_poi to OOB
2173  * @page: page number to write
2174  *
2175  * Not for syndrome calculating ECC controllers, which use a special oob layout.
2176  */
nand_write_page_raw(struct mtd_info * mtd,struct nand_chip * chip,const uint8_t * buf,int oob_required,int page)2177 static int nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
2178 			       const uint8_t *buf, int oob_required, int page)
2179 {
2180 	chip->write_buf(mtd, buf, mtd->writesize);
2181 	if (oob_required)
2182 		chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
2183 
2184 	return 0;
2185 }
2186 
2187 /**
2188  * nand_write_page_raw_syndrome - [INTERN] raw page write function
2189  * @mtd: mtd info structure
2190  * @chip: nand chip info structure
2191  * @buf: data buffer
2192  * @oob_required: must write chip->oob_poi to OOB
2193  * @page: page number to write
2194  *
2195  * We need a special oob layout and handling even when ECC isn't checked.
2196  */
nand_write_page_raw_syndrome(struct mtd_info * mtd,struct nand_chip * chip,const uint8_t * buf,int oob_required,int page)2197 static int nand_write_page_raw_syndrome(struct mtd_info *mtd,
2198 					struct nand_chip *chip,
2199 					const uint8_t *buf, int oob_required,
2200 					int page)
2201 {
2202 	int eccsize = chip->ecc.size;
2203 	int eccbytes = chip->ecc.bytes;
2204 	uint8_t *oob = chip->oob_poi;
2205 	int steps, size;
2206 
2207 	for (steps = chip->ecc.steps; steps > 0; steps--) {
2208 		chip->write_buf(mtd, buf, eccsize);
2209 		buf += eccsize;
2210 
2211 		if (chip->ecc.prepad) {
2212 			chip->write_buf(mtd, oob, chip->ecc.prepad);
2213 			oob += chip->ecc.prepad;
2214 		}
2215 
2216 		chip->write_buf(mtd, oob, eccbytes);
2217 		oob += eccbytes;
2218 
2219 		if (chip->ecc.postpad) {
2220 			chip->write_buf(mtd, oob, chip->ecc.postpad);
2221 			oob += chip->ecc.postpad;
2222 		}
2223 	}
2224 
2225 	size = mtd->oobsize - (oob - chip->oob_poi);
2226 	if (size)
2227 		chip->write_buf(mtd, oob, size);
2228 
2229 	return 0;
2230 }
2231 /**
2232  * nand_write_page_swecc - [REPLACEABLE] software ECC based page write function
2233  * @mtd: mtd info structure
2234  * @chip: nand chip info structure
2235  * @buf: data buffer
2236  * @oob_required: must write chip->oob_poi to OOB
2237  * @page: page number to write
2238  */
nand_write_page_swecc(struct mtd_info * mtd,struct nand_chip * chip,const uint8_t * buf,int oob_required,int page)2239 static int nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
2240 				 const uint8_t *buf, int oob_required,
2241 				 int page)
2242 {
2243 	int i, eccsize = chip->ecc.size;
2244 	int eccbytes = chip->ecc.bytes;
2245 	int eccsteps = chip->ecc.steps;
2246 	uint8_t *ecc_calc = chip->buffers->ecccalc;
2247 	const uint8_t *p = buf;
2248 	uint32_t *eccpos = chip->ecc.layout->eccpos;
2249 
2250 	/* Software ECC calculation */
2251 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
2252 		chip->ecc.calculate(mtd, p, &ecc_calc[i]);
2253 
2254 	for (i = 0; i < chip->ecc.total; i++)
2255 		chip->oob_poi[eccpos[i]] = ecc_calc[i];
2256 
2257 	return chip->ecc.write_page_raw(mtd, chip, buf, 1, page);
2258 }
2259 
2260 /**
2261  * nand_write_page_hwecc - [REPLACEABLE] hardware ECC based page write function
2262  * @mtd: mtd info structure
2263  * @chip: nand chip info structure
2264  * @buf: data buffer
2265  * @oob_required: must write chip->oob_poi to OOB
2266  * @page: page number to write
2267  */
nand_write_page_hwecc(struct mtd_info * mtd,struct nand_chip * chip,const uint8_t * buf,int oob_required,int page)2268 static int nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
2269 				  const uint8_t *buf, int oob_required,
2270 				  int page)
2271 {
2272 	int i, eccsize = chip->ecc.size;
2273 	int eccbytes = chip->ecc.bytes;
2274 	int eccsteps = chip->ecc.steps;
2275 	uint8_t *ecc_calc = chip->buffers->ecccalc;
2276 	const uint8_t *p = buf;
2277 	uint32_t *eccpos = chip->ecc.layout->eccpos;
2278 
2279 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
2280 		chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
2281 		chip->write_buf(mtd, p, eccsize);
2282 		chip->ecc.calculate(mtd, p, &ecc_calc[i]);
2283 	}
2284 
2285 	for (i = 0; i < chip->ecc.total; i++)
2286 		chip->oob_poi[eccpos[i]] = ecc_calc[i];
2287 
2288 	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
2289 
2290 	return 0;
2291 }
2292 
2293 
2294 /**
2295  * nand_write_subpage_hwecc - [REPLACEABLE] hardware ECC based subpage write
2296  * @mtd:	mtd info structure
2297  * @chip:	nand chip info structure
2298  * @offset:	column address of subpage within the page
2299  * @data_len:	data length
2300  * @buf:	data buffer
2301  * @oob_required: must write chip->oob_poi to OOB
2302  * @page: page number to write
2303  */
nand_write_subpage_hwecc(struct mtd_info * mtd,struct nand_chip * chip,uint32_t offset,uint32_t data_len,const uint8_t * buf,int oob_required,int page)2304 static int nand_write_subpage_hwecc(struct mtd_info *mtd,
2305 				struct nand_chip *chip, uint32_t offset,
2306 				uint32_t data_len, const uint8_t *buf,
2307 				int oob_required, int page)
2308 {
2309 	uint8_t *oob_buf  = chip->oob_poi;
2310 	uint8_t *ecc_calc = chip->buffers->ecccalc;
2311 	int ecc_size      = chip->ecc.size;
2312 	int ecc_bytes     = chip->ecc.bytes;
2313 	int ecc_steps     = chip->ecc.steps;
2314 	uint32_t *eccpos  = chip->ecc.layout->eccpos;
2315 	uint32_t start_step = offset / ecc_size;
2316 	uint32_t end_step   = (offset + data_len - 1) / ecc_size;
2317 	int oob_bytes       = mtd->oobsize / ecc_steps;
2318 	int step, i;
2319 
2320 	for (step = 0; step < ecc_steps; step++) {
2321 		/* configure controller for WRITE access */
2322 		chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
2323 
2324 		/* write data (untouched subpages already masked by 0xFF) */
2325 		chip->write_buf(mtd, buf, ecc_size);
2326 
2327 		/* mask ECC of un-touched subpages by padding 0xFF */
2328 		if ((step < start_step) || (step > end_step))
2329 			memset(ecc_calc, 0xff, ecc_bytes);
2330 		else
2331 			chip->ecc.calculate(mtd, buf, ecc_calc);
2332 
2333 		/* mask OOB of un-touched subpages by padding 0xFF */
2334 		/* if oob_required, preserve OOB metadata of written subpage */
2335 		if (!oob_required || (step < start_step) || (step > end_step))
2336 			memset(oob_buf, 0xff, oob_bytes);
2337 
2338 		buf += ecc_size;
2339 		ecc_calc += ecc_bytes;
2340 		oob_buf  += oob_bytes;
2341 	}
2342 
2343 	/* copy calculated ECC for whole page to chip->buffer->oob */
2344 	/* this include masked-value(0xFF) for unwritten subpages */
2345 	ecc_calc = chip->buffers->ecccalc;
2346 	for (i = 0; i < chip->ecc.total; i++)
2347 		chip->oob_poi[eccpos[i]] = ecc_calc[i];
2348 
2349 	/* write OOB buffer to NAND device */
2350 	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
2351 
2352 	return 0;
2353 }
2354 
2355 
2356 /**
2357  * nand_write_page_syndrome - [REPLACEABLE] hardware ECC syndrome based page write
2358  * @mtd: mtd info structure
2359  * @chip: nand chip info structure
2360  * @buf: data buffer
2361  * @oob_required: must write chip->oob_poi to OOB
2362  * @page: page number to write
2363  *
2364  * The hw generator calculates the error syndrome automatically. Therefore we
2365  * need a special oob layout and handling.
2366  */
nand_write_page_syndrome(struct mtd_info * mtd,struct nand_chip * chip,const uint8_t * buf,int oob_required,int page)2367 static int nand_write_page_syndrome(struct mtd_info *mtd,
2368 				    struct nand_chip *chip,
2369 				    const uint8_t *buf, int oob_required,
2370 				    int page)
2371 {
2372 	int i, eccsize = chip->ecc.size;
2373 	int eccbytes = chip->ecc.bytes;
2374 	int eccsteps = chip->ecc.steps;
2375 	const uint8_t *p = buf;
2376 	uint8_t *oob = chip->oob_poi;
2377 
2378 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
2379 
2380 		chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
2381 		chip->write_buf(mtd, p, eccsize);
2382 
2383 		if (chip->ecc.prepad) {
2384 			chip->write_buf(mtd, oob, chip->ecc.prepad);
2385 			oob += chip->ecc.prepad;
2386 		}
2387 
2388 		chip->ecc.calculate(mtd, p, oob);
2389 		chip->write_buf(mtd, oob, eccbytes);
2390 		oob += eccbytes;
2391 
2392 		if (chip->ecc.postpad) {
2393 			chip->write_buf(mtd, oob, chip->ecc.postpad);
2394 			oob += chip->ecc.postpad;
2395 		}
2396 	}
2397 
2398 	/* Calculate remaining oob bytes */
2399 	i = mtd->oobsize - (oob - chip->oob_poi);
2400 	if (i)
2401 		chip->write_buf(mtd, oob, i);
2402 
2403 	return 0;
2404 }
2405 
2406 /**
2407  * nand_write_page - [REPLACEABLE] write one page
2408  * @mtd: MTD device structure
2409  * @chip: NAND chip descriptor
2410  * @offset: address offset within the page
2411  * @data_len: length of actual data to be written
2412  * @buf: the data to write
2413  * @oob_required: must write chip->oob_poi to OOB
2414  * @page: page number to write
2415  * @cached: cached programming
2416  * @raw: use _raw version of write_page
2417  */
nand_write_page(struct mtd_info * mtd,struct nand_chip * chip,uint32_t offset,int data_len,const uint8_t * buf,int oob_required,int page,int cached,int raw)2418 static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
2419 		uint32_t offset, int data_len, const uint8_t *buf,
2420 		int oob_required, int page, int cached, int raw)
2421 {
2422 	int status, subpage;
2423 
2424 	if (!(chip->options & NAND_NO_SUBPAGE_WRITE) &&
2425 		chip->ecc.write_subpage)
2426 		subpage = offset || (data_len < mtd->writesize);
2427 	else
2428 		subpage = 0;
2429 
2430 	chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
2431 
2432 	if (unlikely(raw))
2433 		status = chip->ecc.write_page_raw(mtd, chip, buf,
2434 						  oob_required, page);
2435 	else if (subpage)
2436 		status = chip->ecc.write_subpage(mtd, chip, offset, data_len,
2437 						 buf, oob_required, page);
2438 	else
2439 		status = chip->ecc.write_page(mtd, chip, buf, oob_required,
2440 					      page);
2441 
2442 	if (status < 0)
2443 		return status;
2444 
2445 	/*
2446 	 * Cached progamming disabled for now. Not sure if it's worth the
2447 	 * trouble. The speed gain is not very impressive. (2.3->2.6Mib/s).
2448 	 */
2449 	cached = 0;
2450 
2451 	if (!cached || !NAND_HAS_CACHEPROG(chip)) {
2452 
2453 		chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
2454 		status = chip->waitfunc(mtd, chip);
2455 		/*
2456 		 * See if operation failed and additional status checks are
2457 		 * available.
2458 		 */
2459 		if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2460 			status = chip->errstat(mtd, chip, FL_WRITING, status,
2461 					       page);
2462 
2463 		if (status & NAND_STATUS_FAIL)
2464 			return -EIO;
2465 	} else {
2466 		chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
2467 		status = chip->waitfunc(mtd, chip);
2468 	}
2469 
2470 	return 0;
2471 }
2472 
2473 /**
2474  * nand_fill_oob - [INTERN] Transfer client buffer to oob
2475  * @mtd: MTD device structure
2476  * @oob: oob data buffer
2477  * @len: oob data write length
2478  * @ops: oob ops structure
2479  */
nand_fill_oob(struct mtd_info * mtd,uint8_t * oob,size_t len,struct mtd_oob_ops * ops)2480 static uint8_t *nand_fill_oob(struct mtd_info *mtd, uint8_t *oob, size_t len,
2481 			      struct mtd_oob_ops *ops)
2482 {
2483 	struct nand_chip *chip = mtd->priv;
2484 
2485 	/*
2486 	 * Initialise to all 0xFF, to avoid the possibility of left over OOB
2487 	 * data from a previous OOB read.
2488 	 */
2489 	memset(chip->oob_poi, 0xff, mtd->oobsize);
2490 
2491 	switch (ops->mode) {
2492 
2493 	case MTD_OPS_PLACE_OOB:
2494 	case MTD_OPS_RAW:
2495 		memcpy(chip->oob_poi + ops->ooboffs, oob, len);
2496 		return oob + len;
2497 
2498 	case MTD_OPS_AUTO_OOB: {
2499 		struct nand_oobfree *free = chip->ecc.layout->oobfree;
2500 		uint32_t boffs = 0, woffs = ops->ooboffs;
2501 		size_t bytes = 0;
2502 
2503 		for (; free->length && len; free++, len -= bytes) {
2504 			/* Write request not from offset 0? */
2505 			if (unlikely(woffs)) {
2506 				if (woffs >= free->length) {
2507 					woffs -= free->length;
2508 					continue;
2509 				}
2510 				boffs = free->offset + woffs;
2511 				bytes = min_t(size_t, len,
2512 					      (free->length - woffs));
2513 				woffs = 0;
2514 			} else {
2515 				bytes = min_t(size_t, len, free->length);
2516 				boffs = free->offset;
2517 			}
2518 			memcpy(chip->oob_poi + boffs, oob, bytes);
2519 			oob += bytes;
2520 		}
2521 		return oob;
2522 	}
2523 	default:
2524 		BUG();
2525 	}
2526 	return NULL;
2527 }
2528 
2529 #define NOTALIGNED(x)	((x & (chip->subpagesize - 1)) != 0)
2530 
2531 /**
2532  * nand_do_write_ops - [INTERN] NAND write with ECC
2533  * @mtd: MTD device structure
2534  * @to: offset to write to
2535  * @ops: oob operations description structure
2536  *
2537  * NAND write with ECC.
2538  */
nand_do_write_ops(struct mtd_info * mtd,loff_t to,struct mtd_oob_ops * ops)2539 static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
2540 			     struct mtd_oob_ops *ops)
2541 {
2542 	int chipnr, realpage, page, blockmask, column;
2543 	struct nand_chip *chip = mtd->priv;
2544 	uint32_t writelen = ops->len;
2545 
2546 	uint32_t oobwritelen = ops->ooblen;
2547 	uint32_t oobmaxlen = ops->mode == MTD_OPS_AUTO_OOB ?
2548 				mtd->oobavail : mtd->oobsize;
2549 
2550 	uint8_t *oob = ops->oobbuf;
2551 	uint8_t *buf = ops->datbuf;
2552 	int ret;
2553 	int oob_required = oob ? 1 : 0;
2554 
2555 	ops->retlen = 0;
2556 	if (!writelen)
2557 		return 0;
2558 
2559 	/* Reject writes, which are not page aligned */
2560 	if (NOTALIGNED(to) || NOTALIGNED(ops->len)) {
2561 		pr_notice("%s: attempt to write non page aligned data\n",
2562 			   __func__);
2563 		return -EINVAL;
2564 	}
2565 
2566 	column = to & (mtd->writesize - 1);
2567 
2568 	chipnr = (int)(to >> chip->chip_shift);
2569 	chip->select_chip(mtd, chipnr);
2570 
2571 	/* Check, if it is write protected */
2572 	if (nand_check_wp(mtd)) {
2573 		ret = -EIO;
2574 		goto err_out;
2575 	}
2576 
2577 	realpage = (int)(to >> chip->page_shift);
2578 	page = realpage & chip->pagemask;
2579 	blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
2580 
2581 	/* Invalidate the page cache, when we write to the cached page */
2582 	if (to <= ((loff_t)chip->pagebuf << chip->page_shift) &&
2583 	    ((loff_t)chip->pagebuf << chip->page_shift) < (to + ops->len))
2584 		chip->pagebuf = -1;
2585 
2586 	/* Don't allow multipage oob writes with offset */
2587 	if (oob && ops->ooboffs && (ops->ooboffs + ops->ooblen > oobmaxlen)) {
2588 		ret = -EINVAL;
2589 		goto err_out;
2590 	}
2591 
2592 	while (1) {
2593 		int bytes = mtd->writesize;
2594 		int cached = writelen > bytes && page != blockmask;
2595 		uint8_t *wbuf = buf;
2596 		int use_bufpoi;
2597 		int part_pagewr = (column || writelen < mtd->writesize);
2598 
2599 		if (part_pagewr)
2600 			use_bufpoi = 1;
2601 		else if (chip->options & NAND_USE_BOUNCE_BUFFER)
2602 			use_bufpoi = !virt_addr_valid(buf);
2603 		else
2604 			use_bufpoi = 0;
2605 
2606 		/* Partial page write?, or need to use bounce buffer */
2607 		if (use_bufpoi) {
2608 			pr_debug("%s: using write bounce buffer for buf@%p\n",
2609 					 __func__, buf);
2610 			cached = 0;
2611 			if (part_pagewr)
2612 				bytes = min_t(int, bytes - column, writelen);
2613 			chip->pagebuf = -1;
2614 			memset(chip->buffers->databuf, 0xff, mtd->writesize);
2615 			memcpy(&chip->buffers->databuf[column], buf, bytes);
2616 			wbuf = chip->buffers->databuf;
2617 		}
2618 
2619 		if (unlikely(oob)) {
2620 			size_t len = min(oobwritelen, oobmaxlen);
2621 			oob = nand_fill_oob(mtd, oob, len, ops);
2622 			oobwritelen -= len;
2623 		} else {
2624 			/* We still need to erase leftover OOB data */
2625 			memset(chip->oob_poi, 0xff, mtd->oobsize);
2626 		}
2627 		ret = chip->write_page(mtd, chip, column, bytes, wbuf,
2628 					oob_required, page, cached,
2629 					(ops->mode == MTD_OPS_RAW));
2630 		if (ret)
2631 			break;
2632 
2633 		writelen -= bytes;
2634 		if (!writelen)
2635 			break;
2636 
2637 		column = 0;
2638 		buf += bytes;
2639 		realpage++;
2640 
2641 		page = realpage & chip->pagemask;
2642 		/* Check, if we cross a chip boundary */
2643 		if (!page) {
2644 			chipnr++;
2645 			chip->select_chip(mtd, -1);
2646 			chip->select_chip(mtd, chipnr);
2647 		}
2648 	}
2649 
2650 	ops->retlen = ops->len - writelen;
2651 	if (unlikely(oob))
2652 		ops->oobretlen = ops->ooblen;
2653 
2654 err_out:
2655 	chip->select_chip(mtd, -1);
2656 	return ret;
2657 }
2658 
2659 /**
2660  * panic_nand_write - [MTD Interface] NAND write with ECC
2661  * @mtd: MTD device structure
2662  * @to: offset to write to
2663  * @len: number of bytes to write
2664  * @retlen: pointer to variable to store the number of written bytes
2665  * @buf: the data to write
2666  *
2667  * NAND write with ECC. Used when performing writes in interrupt context, this
2668  * may for example be called by mtdoops when writing an oops while in panic.
2669  */
panic_nand_write(struct mtd_info * mtd,loff_t to,size_t len,size_t * retlen,const uint8_t * buf)2670 static int panic_nand_write(struct mtd_info *mtd, loff_t to, size_t len,
2671 			    size_t *retlen, const uint8_t *buf)
2672 {
2673 	struct nand_chip *chip = mtd->priv;
2674 	int chipnr = (int)(to >> chip->chip_shift);
2675 	struct mtd_oob_ops ops;
2676 	int ret;
2677 
2678 	/* Grab the device */
2679 	panic_nand_get_device(chip, mtd, FL_WRITING);
2680 
2681 	chip->select_chip(mtd, chipnr);
2682 
2683 	/* Wait for the device to get ready */
2684 	panic_nand_wait(mtd, chip, 400);
2685 
2686 	memset(&ops, 0, sizeof(ops));
2687 	ops.len = len;
2688 	ops.datbuf = (uint8_t *)buf;
2689 	ops.mode = MTD_OPS_PLACE_OOB;
2690 
2691 	ret = nand_do_write_ops(mtd, to, &ops);
2692 
2693 	*retlen = ops.retlen;
2694 	return ret;
2695 }
2696 
2697 /**
2698  * nand_write - [MTD Interface] NAND write with ECC
2699  * @mtd: MTD device structure
2700  * @to: offset to write to
2701  * @len: number of bytes to write
2702  * @retlen: pointer to variable to store the number of written bytes
2703  * @buf: the data to write
2704  *
2705  * NAND write with ECC.
2706  */
nand_write(struct mtd_info * mtd,loff_t to,size_t len,size_t * retlen,const uint8_t * buf)2707 static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
2708 			  size_t *retlen, const uint8_t *buf)
2709 {
2710 	struct mtd_oob_ops ops;
2711 	int ret;
2712 
2713 	nand_get_device(mtd, FL_WRITING);
2714 	memset(&ops, 0, sizeof(ops));
2715 	ops.len = len;
2716 	ops.datbuf = (uint8_t *)buf;
2717 	ops.mode = MTD_OPS_PLACE_OOB;
2718 	ret = nand_do_write_ops(mtd, to, &ops);
2719 	*retlen = ops.retlen;
2720 	nand_release_device(mtd);
2721 	return ret;
2722 }
2723 
2724 /**
2725  * nand_do_write_oob - [MTD Interface] NAND write out-of-band
2726  * @mtd: MTD device structure
2727  * @to: offset to write to
2728  * @ops: oob operation description structure
2729  *
2730  * NAND write out-of-band.
2731  */
nand_do_write_oob(struct mtd_info * mtd,loff_t to,struct mtd_oob_ops * ops)2732 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
2733 			     struct mtd_oob_ops *ops)
2734 {
2735 	int chipnr, page, status, len;
2736 	struct nand_chip *chip = mtd->priv;
2737 
2738 	pr_debug("%s: to = 0x%08x, len = %i\n",
2739 			 __func__, (unsigned int)to, (int)ops->ooblen);
2740 
2741 	if (ops->mode == MTD_OPS_AUTO_OOB)
2742 		len = chip->ecc.layout->oobavail;
2743 	else
2744 		len = mtd->oobsize;
2745 
2746 	/* Do not allow write past end of page */
2747 	if ((ops->ooboffs + ops->ooblen) > len) {
2748 		pr_debug("%s: attempt to write past end of page\n",
2749 				__func__);
2750 		return -EINVAL;
2751 	}
2752 
2753 	if (unlikely(ops->ooboffs >= len)) {
2754 		pr_debug("%s: attempt to start write outside oob\n",
2755 				__func__);
2756 		return -EINVAL;
2757 	}
2758 
2759 	/* Do not allow write past end of device */
2760 	if (unlikely(to >= mtd->size ||
2761 		     ops->ooboffs + ops->ooblen >
2762 			((mtd->size >> chip->page_shift) -
2763 			 (to >> chip->page_shift)) * len)) {
2764 		pr_debug("%s: attempt to write beyond end of device\n",
2765 				__func__);
2766 		return -EINVAL;
2767 	}
2768 
2769 	chipnr = (int)(to >> chip->chip_shift);
2770 	chip->select_chip(mtd, chipnr);
2771 
2772 	/* Shift to get page */
2773 	page = (int)(to >> chip->page_shift);
2774 
2775 	/*
2776 	 * Reset the chip. Some chips (like the Toshiba TC5832DC found in one
2777 	 * of my DiskOnChip 2000 test units) will clear the whole data page too
2778 	 * if we don't do this. I have no clue why, but I seem to have 'fixed'
2779 	 * it in the doc2000 driver in August 1999.  dwmw2.
2780 	 */
2781 	chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
2782 
2783 	/* Check, if it is write protected */
2784 	if (nand_check_wp(mtd)) {
2785 		chip->select_chip(mtd, -1);
2786 		return -EROFS;
2787 	}
2788 
2789 	/* Invalidate the page cache, if we write to the cached page */
2790 	if (page == chip->pagebuf)
2791 		chip->pagebuf = -1;
2792 
2793 	nand_fill_oob(mtd, ops->oobbuf, ops->ooblen, ops);
2794 
2795 	if (ops->mode == MTD_OPS_RAW)
2796 		status = chip->ecc.write_oob_raw(mtd, chip, page & chip->pagemask);
2797 	else
2798 		status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
2799 
2800 	chip->select_chip(mtd, -1);
2801 
2802 	if (status)
2803 		return status;
2804 
2805 	ops->oobretlen = ops->ooblen;
2806 
2807 	return 0;
2808 }
2809 
2810 /**
2811  * nand_write_oob - [MTD Interface] NAND write data and/or out-of-band
2812  * @mtd: MTD device structure
2813  * @to: offset to write to
2814  * @ops: oob operation description structure
2815  */
nand_write_oob(struct mtd_info * mtd,loff_t to,struct mtd_oob_ops * ops)2816 static int nand_write_oob(struct mtd_info *mtd, loff_t to,
2817 			  struct mtd_oob_ops *ops)
2818 {
2819 	int ret = -ENOTSUPP;
2820 
2821 	ops->retlen = 0;
2822 
2823 	/* Do not allow writes past end of device */
2824 	if (ops->datbuf && (to + ops->len) > mtd->size) {
2825 		pr_debug("%s: attempt to write beyond end of device\n",
2826 				__func__);
2827 		return -EINVAL;
2828 	}
2829 
2830 	nand_get_device(mtd, FL_WRITING);
2831 
2832 	switch (ops->mode) {
2833 	case MTD_OPS_PLACE_OOB:
2834 	case MTD_OPS_AUTO_OOB:
2835 	case MTD_OPS_RAW:
2836 		break;
2837 
2838 	default:
2839 		goto out;
2840 	}
2841 
2842 	if (!ops->datbuf)
2843 		ret = nand_do_write_oob(mtd, to, ops);
2844 	else
2845 		ret = nand_do_write_ops(mtd, to, ops);
2846 
2847 out:
2848 	nand_release_device(mtd);
2849 	return ret;
2850 }
2851 
2852 /**
2853  * single_erase - [GENERIC] NAND standard block erase command function
2854  * @mtd: MTD device structure
2855  * @page: the page address of the block which will be erased
2856  *
2857  * Standard erase command for NAND chips. Returns NAND status.
2858  */
single_erase(struct mtd_info * mtd,int page)2859 static int single_erase(struct mtd_info *mtd, int page)
2860 {
2861 	struct nand_chip *chip = mtd->priv;
2862 	/* Send commands to erase a block */
2863 	chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
2864 	chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
2865 
2866 	return chip->waitfunc(mtd, chip);
2867 }
2868 
2869 /**
2870  * nand_erase - [MTD Interface] erase block(s)
2871  * @mtd: MTD device structure
2872  * @instr: erase instruction
2873  *
2874  * Erase one ore more blocks.
2875  */
nand_erase(struct mtd_info * mtd,struct erase_info * instr)2876 static int nand_erase(struct mtd_info *mtd, struct erase_info *instr)
2877 {
2878 	return nand_erase_nand(mtd, instr, 0);
2879 }
2880 
2881 /**
2882  * nand_erase_nand - [INTERN] erase block(s)
2883  * @mtd: MTD device structure
2884  * @instr: erase instruction
2885  * @allowbbt: allow erasing the bbt area
2886  *
2887  * Erase one ore more blocks.
2888  */
nand_erase_nand(struct mtd_info * mtd,struct erase_info * instr,int allowbbt)2889 int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
2890 		    int allowbbt)
2891 {
2892 	int page, status, pages_per_block, ret, chipnr;
2893 	struct nand_chip *chip = mtd->priv;
2894 	loff_t len;
2895 
2896 	pr_debug("%s: start = 0x%012llx, len = %llu\n",
2897 			__func__, (unsigned long long)instr->addr,
2898 			(unsigned long long)instr->len);
2899 
2900 	if (check_offs_len(mtd, instr->addr, instr->len))
2901 		return -EINVAL;
2902 
2903 	/* Grab the lock and see if the device is available */
2904 	nand_get_device(mtd, FL_ERASING);
2905 
2906 	/* Shift to get first page */
2907 	page = (int)(instr->addr >> chip->page_shift);
2908 	chipnr = (int)(instr->addr >> chip->chip_shift);
2909 
2910 	/* Calculate pages in each block */
2911 	pages_per_block = 1 << (chip->phys_erase_shift - chip->page_shift);
2912 
2913 	/* Select the NAND device */
2914 	chip->select_chip(mtd, chipnr);
2915 
2916 	/* Check, if it is write protected */
2917 	if (nand_check_wp(mtd)) {
2918 		pr_debug("%s: device is write protected!\n",
2919 				__func__);
2920 		instr->state = MTD_ERASE_FAILED;
2921 		goto erase_exit;
2922 	}
2923 
2924 	/* Loop through the pages */
2925 	len = instr->len;
2926 
2927 	instr->state = MTD_ERASING;
2928 
2929 	while (len) {
2930 		/* Check if we have a bad block, we do not erase bad blocks! */
2931 		if (nand_block_checkbad(mtd, ((loff_t) page) <<
2932 					chip->page_shift, 0, allowbbt)) {
2933 			pr_warn("%s: attempt to erase a bad block at page 0x%08x\n",
2934 				    __func__, page);
2935 			instr->state = MTD_ERASE_FAILED;
2936 			goto erase_exit;
2937 		}
2938 
2939 		/*
2940 		 * Invalidate the page cache, if we erase the block which
2941 		 * contains the current cached page.
2942 		 */
2943 		if (page <= chip->pagebuf && chip->pagebuf <
2944 		    (page + pages_per_block))
2945 			chip->pagebuf = -1;
2946 
2947 		status = chip->erase(mtd, page & chip->pagemask);
2948 
2949 		/*
2950 		 * See if operation failed and additional status checks are
2951 		 * available
2952 		 */
2953 		if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2954 			status = chip->errstat(mtd, chip, FL_ERASING,
2955 					       status, page);
2956 
2957 		/* See if block erase succeeded */
2958 		if (status & NAND_STATUS_FAIL) {
2959 			pr_debug("%s: failed erase, page 0x%08x\n",
2960 					__func__, page);
2961 			instr->state = MTD_ERASE_FAILED;
2962 			instr->fail_addr =
2963 				((loff_t)page << chip->page_shift);
2964 			goto erase_exit;
2965 		}
2966 
2967 		/* Increment page address and decrement length */
2968 		len -= (1ULL << chip->phys_erase_shift);
2969 		page += pages_per_block;
2970 
2971 		/* Check, if we cross a chip boundary */
2972 		if (len && !(page & chip->pagemask)) {
2973 			chipnr++;
2974 			chip->select_chip(mtd, -1);
2975 			chip->select_chip(mtd, chipnr);
2976 		}
2977 	}
2978 	instr->state = MTD_ERASE_DONE;
2979 
2980 erase_exit:
2981 
2982 	ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
2983 
2984 	/* Deselect and wake up anyone waiting on the device */
2985 	chip->select_chip(mtd, -1);
2986 	nand_release_device(mtd);
2987 
2988 	/* Do call back function */
2989 	if (!ret)
2990 		mtd_erase_callback(instr);
2991 
2992 	/* Return more or less happy */
2993 	return ret;
2994 }
2995 
2996 /**
2997  * nand_sync - [MTD Interface] sync
2998  * @mtd: MTD device structure
2999  *
3000  * Sync is actually a wait for chip ready function.
3001  */
nand_sync(struct mtd_info * mtd)3002 static void nand_sync(struct mtd_info *mtd)
3003 {
3004 	pr_debug("%s: called\n", __func__);
3005 
3006 	/* Grab the lock and see if the device is available */
3007 	nand_get_device(mtd, FL_SYNCING);
3008 	/* Release it and go back */
3009 	nand_release_device(mtd);
3010 }
3011 
3012 /**
3013  * nand_block_isbad - [MTD Interface] Check if block at offset is bad
3014  * @mtd: MTD device structure
3015  * @offs: offset relative to mtd start
3016  */
nand_block_isbad(struct mtd_info * mtd,loff_t offs)3017 static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
3018 {
3019 	return nand_block_checkbad(mtd, offs, 1, 0);
3020 }
3021 
3022 /**
3023  * nand_block_markbad - [MTD Interface] Mark block at the given offset as bad
3024  * @mtd: MTD device structure
3025  * @ofs: offset relative to mtd start
3026  */
nand_block_markbad(struct mtd_info * mtd,loff_t ofs)3027 static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
3028 {
3029 	int ret;
3030 
3031 	ret = nand_block_isbad(mtd, ofs);
3032 	if (ret) {
3033 		/* If it was bad already, return success and do nothing */
3034 		if (ret > 0)
3035 			return 0;
3036 		return ret;
3037 	}
3038 
3039 	return nand_block_markbad_lowlevel(mtd, ofs);
3040 }
3041 
3042 /**
3043  * nand_onfi_set_features- [REPLACEABLE] set features for ONFI nand
3044  * @mtd: MTD device structure
3045  * @chip: nand chip info structure
3046  * @addr: feature address.
3047  * @subfeature_param: the subfeature parameters, a four bytes array.
3048  */
nand_onfi_set_features(struct mtd_info * mtd,struct nand_chip * chip,int addr,uint8_t * subfeature_param)3049 static int nand_onfi_set_features(struct mtd_info *mtd, struct nand_chip *chip,
3050 			int addr, uint8_t *subfeature_param)
3051 {
3052 	int status;
3053 	int i;
3054 
3055 	if (!chip->onfi_version ||
3056 	    !(le16_to_cpu(chip->onfi_params.opt_cmd)
3057 	      & ONFI_OPT_CMD_SET_GET_FEATURES))
3058 		return -EINVAL;
3059 
3060 	chip->cmdfunc(mtd, NAND_CMD_SET_FEATURES, addr, -1);
3061 	for (i = 0; i < ONFI_SUBFEATURE_PARAM_LEN; ++i)
3062 		chip->write_byte(mtd, subfeature_param[i]);
3063 
3064 	status = chip->waitfunc(mtd, chip);
3065 	if (status & NAND_STATUS_FAIL)
3066 		return -EIO;
3067 	return 0;
3068 }
3069 
3070 /**
3071  * nand_onfi_get_features- [REPLACEABLE] get features for ONFI nand
3072  * @mtd: MTD device structure
3073  * @chip: nand chip info structure
3074  * @addr: feature address.
3075  * @subfeature_param: the subfeature parameters, a four bytes array.
3076  */
nand_onfi_get_features(struct mtd_info * mtd,struct nand_chip * chip,int addr,uint8_t * subfeature_param)3077 static int nand_onfi_get_features(struct mtd_info *mtd, struct nand_chip *chip,
3078 			int addr, uint8_t *subfeature_param)
3079 {
3080 	int i;
3081 
3082 	if (!chip->onfi_version ||
3083 	    !(le16_to_cpu(chip->onfi_params.opt_cmd)
3084 	      & ONFI_OPT_CMD_SET_GET_FEATURES))
3085 		return -EINVAL;
3086 
3087 	chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES, addr, -1);
3088 	for (i = 0; i < ONFI_SUBFEATURE_PARAM_LEN; ++i)
3089 		*subfeature_param++ = chip->read_byte(mtd);
3090 	return 0;
3091 }
3092 
3093 /**
3094  * nand_suspend - [MTD Interface] Suspend the NAND flash
3095  * @mtd: MTD device structure
3096  */
nand_suspend(struct mtd_info * mtd)3097 static int nand_suspend(struct mtd_info *mtd)
3098 {
3099 	return nand_get_device(mtd, FL_PM_SUSPENDED);
3100 }
3101 
3102 /**
3103  * nand_resume - [MTD Interface] Resume the NAND flash
3104  * @mtd: MTD device structure
3105  */
nand_resume(struct mtd_info * mtd)3106 static void nand_resume(struct mtd_info *mtd)
3107 {
3108 	struct nand_chip *chip = mtd->priv;
3109 
3110 	if (chip->state == FL_PM_SUSPENDED)
3111 		nand_release_device(mtd);
3112 	else
3113 		pr_err("%s called for a chip which is not in suspended state\n",
3114 			__func__);
3115 }
3116 
3117 /**
3118  * nand_shutdown - [MTD Interface] Finish the current NAND operation and
3119  *                 prevent further operations
3120  * @mtd: MTD device structure
3121  */
nand_shutdown(struct mtd_info * mtd)3122 static void nand_shutdown(struct mtd_info *mtd)
3123 {
3124 	nand_get_device(mtd, FL_PM_SUSPENDED);
3125 }
3126 
3127 /* Set default functions */
nand_set_defaults(struct nand_chip * chip,int busw)3128 static void nand_set_defaults(struct nand_chip *chip, int busw)
3129 {
3130 	/* check for proper chip_delay setup, set 20us if not */
3131 	if (!chip->chip_delay)
3132 		chip->chip_delay = 20;
3133 
3134 	/* check, if a user supplied command function given */
3135 	if (chip->cmdfunc == NULL)
3136 		chip->cmdfunc = nand_command;
3137 
3138 	/* check, if a user supplied wait function given */
3139 	if (chip->waitfunc == NULL)
3140 		chip->waitfunc = nand_wait;
3141 
3142 	if (!chip->select_chip)
3143 		chip->select_chip = nand_select_chip;
3144 
3145 	/* set for ONFI nand */
3146 	if (!chip->onfi_set_features)
3147 		chip->onfi_set_features = nand_onfi_set_features;
3148 	if (!chip->onfi_get_features)
3149 		chip->onfi_get_features = nand_onfi_get_features;
3150 
3151 	/* If called twice, pointers that depend on busw may need to be reset */
3152 	if (!chip->read_byte || chip->read_byte == nand_read_byte)
3153 		chip->read_byte = busw ? nand_read_byte16 : nand_read_byte;
3154 	if (!chip->read_word)
3155 		chip->read_word = nand_read_word;
3156 	if (!chip->block_bad)
3157 		chip->block_bad = nand_block_bad;
3158 	if (!chip->block_markbad)
3159 		chip->block_markbad = nand_default_block_markbad;
3160 	if (!chip->write_buf || chip->write_buf == nand_write_buf)
3161 		chip->write_buf = busw ? nand_write_buf16 : nand_write_buf;
3162 	if (!chip->write_byte || chip->write_byte == nand_write_byte)
3163 		chip->write_byte = busw ? nand_write_byte16 : nand_write_byte;
3164 	if (!chip->read_buf || chip->read_buf == nand_read_buf)
3165 		chip->read_buf = busw ? nand_read_buf16 : nand_read_buf;
3166 	if (!chip->scan_bbt)
3167 		chip->scan_bbt = nand_default_bbt;
3168 
3169 	if (!chip->controller) {
3170 		chip->controller = &chip->hwcontrol;
3171 		spin_lock_init(&chip->controller->lock);
3172 		init_waitqueue_head(&chip->controller->wq);
3173 	}
3174 
3175 }
3176 
3177 /* Sanitize ONFI strings so we can safely print them */
sanitize_string(uint8_t * s,size_t len)3178 static void sanitize_string(uint8_t *s, size_t len)
3179 {
3180 	ssize_t i;
3181 
3182 	/* Null terminate */
3183 	s[len - 1] = 0;
3184 
3185 	/* Remove non printable chars */
3186 	for (i = 0; i < len - 1; i++) {
3187 		if (s[i] < ' ' || s[i] > 127)
3188 			s[i] = '?';
3189 	}
3190 
3191 	/* Remove trailing spaces */
3192 	strim(s);
3193 }
3194 
onfi_crc16(u16 crc,u8 const * p,size_t len)3195 static u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
3196 {
3197 	int i;
3198 	while (len--) {
3199 		crc ^= *p++ << 8;
3200 		for (i = 0; i < 8; i++)
3201 			crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
3202 	}
3203 
3204 	return crc;
3205 }
3206 
3207 /* Parse the Extended Parameter Page. */
nand_flash_detect_ext_param_page(struct mtd_info * mtd,struct nand_chip * chip,struct nand_onfi_params * p)3208 static int nand_flash_detect_ext_param_page(struct mtd_info *mtd,
3209 		struct nand_chip *chip, struct nand_onfi_params *p)
3210 {
3211 	struct onfi_ext_param_page *ep;
3212 	struct onfi_ext_section *s;
3213 	struct onfi_ext_ecc_info *ecc;
3214 	uint8_t *cursor;
3215 	int ret = -EINVAL;
3216 	int len;
3217 	int i;
3218 
3219 	len = le16_to_cpu(p->ext_param_page_length) * 16;
3220 	ep = kmalloc(len, GFP_KERNEL);
3221 	if (!ep)
3222 		return -ENOMEM;
3223 
3224 	/* Send our own NAND_CMD_PARAM. */
3225 	chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
3226 
3227 	/* Use the Change Read Column command to skip the ONFI param pages. */
3228 	chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
3229 			sizeof(*p) * p->num_of_param_pages , -1);
3230 
3231 	/* Read out the Extended Parameter Page. */
3232 	chip->read_buf(mtd, (uint8_t *)ep, len);
3233 	if ((onfi_crc16(ONFI_CRC_BASE, ((uint8_t *)ep) + 2, len - 2)
3234 		!= le16_to_cpu(ep->crc))) {
3235 		pr_debug("fail in the CRC.\n");
3236 		goto ext_out;
3237 	}
3238 
3239 	/*
3240 	 * Check the signature.
3241 	 * Do not strictly follow the ONFI spec, maybe changed in future.
3242 	 */
3243 	if (strncmp(ep->sig, "EPPS", 4)) {
3244 		pr_debug("The signature is invalid.\n");
3245 		goto ext_out;
3246 	}
3247 
3248 	/* find the ECC section. */
3249 	cursor = (uint8_t *)(ep + 1);
3250 	for (i = 0; i < ONFI_EXT_SECTION_MAX; i++) {
3251 		s = ep->sections + i;
3252 		if (s->type == ONFI_SECTION_TYPE_2)
3253 			break;
3254 		cursor += s->length * 16;
3255 	}
3256 	if (i == ONFI_EXT_SECTION_MAX) {
3257 		pr_debug("We can not find the ECC section.\n");
3258 		goto ext_out;
3259 	}
3260 
3261 	/* get the info we want. */
3262 	ecc = (struct onfi_ext_ecc_info *)cursor;
3263 
3264 	if (!ecc->codeword_size) {
3265 		pr_debug("Invalid codeword size\n");
3266 		goto ext_out;
3267 	}
3268 
3269 	chip->ecc_strength_ds = ecc->ecc_bits;
3270 	chip->ecc_step_ds = 1 << ecc->codeword_size;
3271 	ret = 0;
3272 
3273 ext_out:
3274 	kfree(ep);
3275 	return ret;
3276 }
3277 
nand_setup_read_retry_micron(struct mtd_info * mtd,int retry_mode)3278 static int nand_setup_read_retry_micron(struct mtd_info *mtd, int retry_mode)
3279 {
3280 	struct nand_chip *chip = mtd->priv;
3281 	uint8_t feature[ONFI_SUBFEATURE_PARAM_LEN] = {retry_mode};
3282 
3283 	return chip->onfi_set_features(mtd, chip, ONFI_FEATURE_ADDR_READ_RETRY,
3284 			feature);
3285 }
3286 
3287 /*
3288  * Configure chip properties from Micron vendor-specific ONFI table
3289  */
nand_onfi_detect_micron(struct nand_chip * chip,struct nand_onfi_params * p)3290 static void nand_onfi_detect_micron(struct nand_chip *chip,
3291 		struct nand_onfi_params *p)
3292 {
3293 	struct nand_onfi_vendor_micron *micron = (void *)p->vendor;
3294 
3295 	if (le16_to_cpu(p->vendor_revision) < 1)
3296 		return;
3297 
3298 	chip->read_retries = micron->read_retry_options;
3299 	chip->setup_read_retry = nand_setup_read_retry_micron;
3300 }
3301 
3302 /*
3303  * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
3304  */
nand_flash_detect_onfi(struct mtd_info * mtd,struct nand_chip * chip,int * busw)3305 static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip,
3306 					int *busw)
3307 {
3308 	struct nand_onfi_params *p = &chip->onfi_params;
3309 	int i, j;
3310 	int val;
3311 
3312 	/* Try ONFI for unknown chip or LP */
3313 	chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1);
3314 	if (chip->read_byte(mtd) != 'O' || chip->read_byte(mtd) != 'N' ||
3315 		chip->read_byte(mtd) != 'F' || chip->read_byte(mtd) != 'I')
3316 		return 0;
3317 
3318 	chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
3319 	for (i = 0; i < 3; i++) {
3320 		for (j = 0; j < sizeof(*p); j++)
3321 			((uint8_t *)p)[j] = chip->read_byte(mtd);
3322 		if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 254) ==
3323 				le16_to_cpu(p->crc)) {
3324 			break;
3325 		}
3326 	}
3327 
3328 	if (i == 3) {
3329 		pr_err("Could not find valid ONFI parameter page; aborting\n");
3330 		return 0;
3331 	}
3332 
3333 	/* Check version */
3334 	val = le16_to_cpu(p->revision);
3335 	if (val & (1 << 5))
3336 		chip->onfi_version = 23;
3337 	else if (val & (1 << 4))
3338 		chip->onfi_version = 22;
3339 	else if (val & (1 << 3))
3340 		chip->onfi_version = 21;
3341 	else if (val & (1 << 2))
3342 		chip->onfi_version = 20;
3343 	else if (val & (1 << 1))
3344 		chip->onfi_version = 10;
3345 
3346 	if (!chip->onfi_version) {
3347 		pr_info("unsupported ONFI version: %d\n", val);
3348 		return 0;
3349 	}
3350 
3351 	sanitize_string(p->manufacturer, sizeof(p->manufacturer));
3352 	sanitize_string(p->model, sizeof(p->model));
3353 	if (!mtd->name)
3354 		mtd->name = p->model;
3355 
3356 	mtd->writesize = le32_to_cpu(p->byte_per_page);
3357 
3358 	/*
3359 	 * pages_per_block and blocks_per_lun may not be a power-of-2 size
3360 	 * (don't ask me who thought of this...). MTD assumes that these
3361 	 * dimensions will be power-of-2, so just truncate the remaining area.
3362 	 */
3363 	mtd->erasesize = 1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
3364 	mtd->erasesize *= mtd->writesize;
3365 
3366 	mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
3367 
3368 	/* See erasesize comment */
3369 	chip->chipsize = 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
3370 	chip->chipsize *= (uint64_t)mtd->erasesize * p->lun_count;
3371 	chip->bits_per_cell = p->bits_per_cell;
3372 
3373 	if (onfi_feature(chip) & ONFI_FEATURE_16_BIT_BUS)
3374 		*busw = NAND_BUSWIDTH_16;
3375 	else
3376 		*busw = 0;
3377 
3378 	if (p->ecc_bits != 0xff) {
3379 		chip->ecc_strength_ds = p->ecc_bits;
3380 		chip->ecc_step_ds = 512;
3381 	} else if (chip->onfi_version >= 21 &&
3382 		(onfi_feature(chip) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
3383 
3384 		/*
3385 		 * The nand_flash_detect_ext_param_page() uses the
3386 		 * Change Read Column command which maybe not supported
3387 		 * by the chip->cmdfunc. So try to update the chip->cmdfunc
3388 		 * now. We do not replace user supplied command function.
3389 		 */
3390 		if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
3391 			chip->cmdfunc = nand_command_lp;
3392 
3393 		/* The Extended Parameter Page is supported since ONFI 2.1. */
3394 		if (nand_flash_detect_ext_param_page(mtd, chip, p))
3395 			pr_warn("Failed to detect ONFI extended param page\n");
3396 	} else {
3397 		pr_warn("Could not retrieve ONFI ECC requirements\n");
3398 	}
3399 
3400 	if (p->jedec_id == NAND_MFR_MICRON)
3401 		nand_onfi_detect_micron(chip, p);
3402 
3403 	return 1;
3404 }
3405 
3406 /*
3407  * Check if the NAND chip is JEDEC compliant, returns 1 if it is, 0 otherwise.
3408  */
nand_flash_detect_jedec(struct mtd_info * mtd,struct nand_chip * chip,int * busw)3409 static int nand_flash_detect_jedec(struct mtd_info *mtd, struct nand_chip *chip,
3410 					int *busw)
3411 {
3412 	struct nand_jedec_params *p = &chip->jedec_params;
3413 	struct jedec_ecc_info *ecc;
3414 	int val;
3415 	int i, j;
3416 
3417 	/* Try JEDEC for unknown chip or LP */
3418 	chip->cmdfunc(mtd, NAND_CMD_READID, 0x40, -1);
3419 	if (chip->read_byte(mtd) != 'J' || chip->read_byte(mtd) != 'E' ||
3420 		chip->read_byte(mtd) != 'D' || chip->read_byte(mtd) != 'E' ||
3421 		chip->read_byte(mtd) != 'C')
3422 		return 0;
3423 
3424 	chip->cmdfunc(mtd, NAND_CMD_PARAM, 0x40, -1);
3425 	for (i = 0; i < 3; i++) {
3426 		for (j = 0; j < sizeof(*p); j++)
3427 			((uint8_t *)p)[j] = chip->read_byte(mtd);
3428 
3429 		if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 510) ==
3430 				le16_to_cpu(p->crc))
3431 			break;
3432 	}
3433 
3434 	if (i == 3) {
3435 		pr_err("Could not find valid JEDEC parameter page; aborting\n");
3436 		return 0;
3437 	}
3438 
3439 	/* Check version */
3440 	val = le16_to_cpu(p->revision);
3441 	if (val & (1 << 2))
3442 		chip->jedec_version = 10;
3443 	else if (val & (1 << 1))
3444 		chip->jedec_version = 1; /* vendor specific version */
3445 
3446 	if (!chip->jedec_version) {
3447 		pr_info("unsupported JEDEC version: %d\n", val);
3448 		return 0;
3449 	}
3450 
3451 	sanitize_string(p->manufacturer, sizeof(p->manufacturer));
3452 	sanitize_string(p->model, sizeof(p->model));
3453 	if (!mtd->name)
3454 		mtd->name = p->model;
3455 
3456 	mtd->writesize = le32_to_cpu(p->byte_per_page);
3457 
3458 	/* Please reference to the comment for nand_flash_detect_onfi. */
3459 	mtd->erasesize = 1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
3460 	mtd->erasesize *= mtd->writesize;
3461 
3462 	mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
3463 
3464 	/* Please reference to the comment for nand_flash_detect_onfi. */
3465 	chip->chipsize = 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
3466 	chip->chipsize *= (uint64_t)mtd->erasesize * p->lun_count;
3467 	chip->bits_per_cell = p->bits_per_cell;
3468 
3469 	if (jedec_feature(chip) & JEDEC_FEATURE_16_BIT_BUS)
3470 		*busw = NAND_BUSWIDTH_16;
3471 	else
3472 		*busw = 0;
3473 
3474 	/* ECC info */
3475 	ecc = &p->ecc_info[0];
3476 
3477 	if (ecc->codeword_size >= 9) {
3478 		chip->ecc_strength_ds = ecc->ecc_bits;
3479 		chip->ecc_step_ds = 1 << ecc->codeword_size;
3480 	} else {
3481 		pr_warn("Invalid codeword size\n");
3482 	}
3483 
3484 	return 1;
3485 }
3486 
3487 /*
3488  * nand_id_has_period - Check if an ID string has a given wraparound period
3489  * @id_data: the ID string
3490  * @arrlen: the length of the @id_data array
3491  * @period: the period of repitition
3492  *
3493  * Check if an ID string is repeated within a given sequence of bytes at
3494  * specific repetition interval period (e.g., {0x20,0x01,0x7F,0x20} has a
3495  * period of 3). This is a helper function for nand_id_len(). Returns non-zero
3496  * if the repetition has a period of @period; otherwise, returns zero.
3497  */
nand_id_has_period(u8 * id_data,int arrlen,int period)3498 static int nand_id_has_period(u8 *id_data, int arrlen, int period)
3499 {
3500 	int i, j;
3501 	for (i = 0; i < period; i++)
3502 		for (j = i + period; j < arrlen; j += period)
3503 			if (id_data[i] != id_data[j])
3504 				return 0;
3505 	return 1;
3506 }
3507 
3508 /*
3509  * nand_id_len - Get the length of an ID string returned by CMD_READID
3510  * @id_data: the ID string
3511  * @arrlen: the length of the @id_data array
3512 
3513  * Returns the length of the ID string, according to known wraparound/trailing
3514  * zero patterns. If no pattern exists, returns the length of the array.
3515  */
nand_id_len(u8 * id_data,int arrlen)3516 static int nand_id_len(u8 *id_data, int arrlen)
3517 {
3518 	int last_nonzero, period;
3519 
3520 	/* Find last non-zero byte */
3521 	for (last_nonzero = arrlen - 1; last_nonzero >= 0; last_nonzero--)
3522 		if (id_data[last_nonzero])
3523 			break;
3524 
3525 	/* All zeros */
3526 	if (last_nonzero < 0)
3527 		return 0;
3528 
3529 	/* Calculate wraparound period */
3530 	for (period = 1; period < arrlen; period++)
3531 		if (nand_id_has_period(id_data, arrlen, period))
3532 			break;
3533 
3534 	/* There's a repeated pattern */
3535 	if (period < arrlen)
3536 		return period;
3537 
3538 	/* There are trailing zeros */
3539 	if (last_nonzero < arrlen - 1)
3540 		return last_nonzero + 1;
3541 
3542 	/* No pattern detected */
3543 	return arrlen;
3544 }
3545 
3546 /* Extract the bits of per cell from the 3rd byte of the extended ID */
nand_get_bits_per_cell(u8 cellinfo)3547 static int nand_get_bits_per_cell(u8 cellinfo)
3548 {
3549 	int bits;
3550 
3551 	bits = cellinfo & NAND_CI_CELLTYPE_MSK;
3552 	bits >>= NAND_CI_CELLTYPE_SHIFT;
3553 	return bits + 1;
3554 }
3555 
3556 /*
3557  * Many new NAND share similar device ID codes, which represent the size of the
3558  * chip. The rest of the parameters must be decoded according to generic or
3559  * manufacturer-specific "extended ID" decoding patterns.
3560  */
nand_decode_ext_id(struct mtd_info * mtd,struct nand_chip * chip,u8 id_data[8],int * busw)3561 static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
3562 				u8 id_data[8], int *busw)
3563 {
3564 	int extid, id_len;
3565 	/* The 3rd id byte holds MLC / multichip data */
3566 	chip->bits_per_cell = nand_get_bits_per_cell(id_data[2]);
3567 	/* The 4th id byte is the important one */
3568 	extid = id_data[3];
3569 
3570 	id_len = nand_id_len(id_data, 8);
3571 
3572 	/*
3573 	 * Field definitions are in the following datasheets:
3574 	 * Old style (4,5 byte ID): Samsung K9GAG08U0M (p.32)
3575 	 * New Samsung (6 byte ID): Samsung K9GAG08U0F (p.44)
3576 	 * Hynix MLC   (6 byte ID): Hynix H27UBG8T2B (p.22)
3577 	 *
3578 	 * Check for ID length, non-zero 6th byte, cell type, and Hynix/Samsung
3579 	 * ID to decide what to do.
3580 	 */
3581 	if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG &&
3582 			!nand_is_slc(chip) && id_data[5] != 0x00) {
3583 		/* Calc pagesize */
3584 		mtd->writesize = 2048 << (extid & 0x03);
3585 		extid >>= 2;
3586 		/* Calc oobsize */
3587 		switch (((extid >> 2) & 0x04) | (extid & 0x03)) {
3588 		case 1:
3589 			mtd->oobsize = 128;
3590 			break;
3591 		case 2:
3592 			mtd->oobsize = 218;
3593 			break;
3594 		case 3:
3595 			mtd->oobsize = 400;
3596 			break;
3597 		case 4:
3598 			mtd->oobsize = 436;
3599 			break;
3600 		case 5:
3601 			mtd->oobsize = 512;
3602 			break;
3603 		case 6:
3604 			mtd->oobsize = 640;
3605 			break;
3606 		case 7:
3607 		default: /* Other cases are "reserved" (unknown) */
3608 			mtd->oobsize = 1024;
3609 			break;
3610 		}
3611 		extid >>= 2;
3612 		/* Calc blocksize */
3613 		mtd->erasesize = (128 * 1024) <<
3614 			(((extid >> 1) & 0x04) | (extid & 0x03));
3615 		*busw = 0;
3616 	} else if (id_len == 6 && id_data[0] == NAND_MFR_HYNIX &&
3617 			!nand_is_slc(chip)) {
3618 		unsigned int tmp;
3619 
3620 		/* Calc pagesize */
3621 		mtd->writesize = 2048 << (extid & 0x03);
3622 		extid >>= 2;
3623 		/* Calc oobsize */
3624 		switch (((extid >> 2) & 0x04) | (extid & 0x03)) {
3625 		case 0:
3626 			mtd->oobsize = 128;
3627 			break;
3628 		case 1:
3629 			mtd->oobsize = 224;
3630 			break;
3631 		case 2:
3632 			mtd->oobsize = 448;
3633 			break;
3634 		case 3:
3635 			mtd->oobsize = 64;
3636 			break;
3637 		case 4:
3638 			mtd->oobsize = 32;
3639 			break;
3640 		case 5:
3641 			mtd->oobsize = 16;
3642 			break;
3643 		default:
3644 			mtd->oobsize = 640;
3645 			break;
3646 		}
3647 		extid >>= 2;
3648 		/* Calc blocksize */
3649 		tmp = ((extid >> 1) & 0x04) | (extid & 0x03);
3650 		if (tmp < 0x03)
3651 			mtd->erasesize = (128 * 1024) << tmp;
3652 		else if (tmp == 0x03)
3653 			mtd->erasesize = 768 * 1024;
3654 		else
3655 			mtd->erasesize = (64 * 1024) << tmp;
3656 		*busw = 0;
3657 	} else {
3658 		/* Calc pagesize */
3659 		mtd->writesize = 1024 << (extid & 0x03);
3660 		extid >>= 2;
3661 		/* Calc oobsize */
3662 		mtd->oobsize = (8 << (extid & 0x01)) *
3663 			(mtd->writesize >> 9);
3664 		extid >>= 2;
3665 		/* Calc blocksize. Blocksize is multiples of 64KiB */
3666 		mtd->erasesize = (64 * 1024) << (extid & 0x03);
3667 		extid >>= 2;
3668 		/* Get buswidth information */
3669 		*busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
3670 
3671 		/*
3672 		 * Toshiba 24nm raw SLC (i.e., not BENAND) have 32B OOB per
3673 		 * 512B page. For Toshiba SLC, we decode the 5th/6th byte as
3674 		 * follows:
3675 		 * - ID byte 6, bits[2:0]: 100b -> 43nm, 101b -> 32nm,
3676 		 *                         110b -> 24nm
3677 		 * - ID byte 5, bit[7]:    1 -> BENAND, 0 -> raw SLC
3678 		 */
3679 		if (id_len >= 6 && id_data[0] == NAND_MFR_TOSHIBA &&
3680 				nand_is_slc(chip) &&
3681 				(id_data[5] & 0x7) == 0x6 /* 24nm */ &&
3682 				!(id_data[4] & 0x80) /* !BENAND */) {
3683 			mtd->oobsize = 32 * mtd->writesize >> 9;
3684 		}
3685 
3686 	}
3687 }
3688 
3689 /*
3690  * Old devices have chip data hardcoded in the device ID table. nand_decode_id
3691  * decodes a matching ID table entry and assigns the MTD size parameters for
3692  * the chip.
3693  */
nand_decode_id(struct mtd_info * mtd,struct nand_chip * chip,struct nand_flash_dev * type,u8 id_data[8],int * busw)3694 static void nand_decode_id(struct mtd_info *mtd, struct nand_chip *chip,
3695 				struct nand_flash_dev *type, u8 id_data[8],
3696 				int *busw)
3697 {
3698 	int maf_id = id_data[0];
3699 
3700 	mtd->erasesize = type->erasesize;
3701 	mtd->writesize = type->pagesize;
3702 	mtd->oobsize = mtd->writesize / 32;
3703 	*busw = type->options & NAND_BUSWIDTH_16;
3704 
3705 	/* All legacy ID NAND are small-page, SLC */
3706 	chip->bits_per_cell = 1;
3707 
3708 	/*
3709 	 * Check for Spansion/AMD ID + repeating 5th, 6th byte since
3710 	 * some Spansion chips have erasesize that conflicts with size
3711 	 * listed in nand_ids table.
3712 	 * Data sheet (5 byte ID): Spansion S30ML-P ORNAND (p.39)
3713 	 */
3714 	if (maf_id == NAND_MFR_AMD && id_data[4] != 0x00 && id_data[5] == 0x00
3715 			&& id_data[6] == 0x00 && id_data[7] == 0x00
3716 			&& mtd->writesize == 512) {
3717 		mtd->erasesize = 128 * 1024;
3718 		mtd->erasesize <<= ((id_data[3] & 0x03) << 1);
3719 	}
3720 }
3721 
3722 /*
3723  * Set the bad block marker/indicator (BBM/BBI) patterns according to some
3724  * heuristic patterns using various detected parameters (e.g., manufacturer,
3725  * page size, cell-type information).
3726  */
nand_decode_bbm_options(struct mtd_info * mtd,struct nand_chip * chip,u8 id_data[8])3727 static void nand_decode_bbm_options(struct mtd_info *mtd,
3728 				    struct nand_chip *chip, u8 id_data[8])
3729 {
3730 	int maf_id = id_data[0];
3731 
3732 	/* Set the bad block position */
3733 	if (mtd->writesize > 512 || (chip->options & NAND_BUSWIDTH_16))
3734 		chip->badblockpos = NAND_LARGE_BADBLOCK_POS;
3735 	else
3736 		chip->badblockpos = NAND_SMALL_BADBLOCK_POS;
3737 
3738 	/*
3739 	 * Bad block marker is stored in the last page of each block on Samsung
3740 	 * and Hynix MLC devices; stored in first two pages of each block on
3741 	 * Micron devices with 2KiB pages and on SLC Samsung, Hynix, Toshiba,
3742 	 * AMD/Spansion, and Macronix.  All others scan only the first page.
3743 	 */
3744 	if (!nand_is_slc(chip) &&
3745 			(maf_id == NAND_MFR_SAMSUNG ||
3746 			 maf_id == NAND_MFR_HYNIX))
3747 		chip->bbt_options |= NAND_BBT_SCANLASTPAGE;
3748 	else if ((nand_is_slc(chip) &&
3749 				(maf_id == NAND_MFR_SAMSUNG ||
3750 				 maf_id == NAND_MFR_HYNIX ||
3751 				 maf_id == NAND_MFR_TOSHIBA ||
3752 				 maf_id == NAND_MFR_AMD ||
3753 				 maf_id == NAND_MFR_MACRONIX)) ||
3754 			(mtd->writesize == 2048 &&
3755 			 maf_id == NAND_MFR_MICRON))
3756 		chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
3757 }
3758 
is_full_id_nand(struct nand_flash_dev * type)3759 static inline bool is_full_id_nand(struct nand_flash_dev *type)
3760 {
3761 	return type->id_len;
3762 }
3763 
find_full_id_nand(struct mtd_info * mtd,struct nand_chip * chip,struct nand_flash_dev * type,u8 * id_data,int * busw)3764 static bool find_full_id_nand(struct mtd_info *mtd, struct nand_chip *chip,
3765 		   struct nand_flash_dev *type, u8 *id_data, int *busw)
3766 {
3767 	if (!strncmp(type->id, id_data, type->id_len)) {
3768 		mtd->writesize = type->pagesize;
3769 		mtd->erasesize = type->erasesize;
3770 		mtd->oobsize = type->oobsize;
3771 
3772 		chip->bits_per_cell = nand_get_bits_per_cell(id_data[2]);
3773 		chip->chipsize = (uint64_t)type->chipsize << 20;
3774 		chip->options |= type->options;
3775 		chip->ecc_strength_ds = NAND_ECC_STRENGTH(type);
3776 		chip->ecc_step_ds = NAND_ECC_STEP(type);
3777 		chip->onfi_timing_mode_default =
3778 					type->onfi_timing_mode_default;
3779 
3780 		*busw = type->options & NAND_BUSWIDTH_16;
3781 
3782 		if (!mtd->name)
3783 			mtd->name = type->name;
3784 
3785 		return true;
3786 	}
3787 	return false;
3788 }
3789 
3790 /*
3791  * Get the flash and manufacturer id and lookup if the type is supported.
3792  */
nand_get_flash_type(struct mtd_info * mtd,struct nand_chip * chip,int * maf_id,int * dev_id,struct nand_flash_dev * type)3793 static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
3794 						  struct nand_chip *chip,
3795 						  int *maf_id, int *dev_id,
3796 						  struct nand_flash_dev *type)
3797 {
3798 	int busw;
3799 	int i, maf_idx;
3800 	u8 id_data[8];
3801 
3802 	/* Select the device */
3803 	chip->select_chip(mtd, 0);
3804 
3805 	/*
3806 	 * Reset the chip, required by some chips (e.g. Micron MT29FxGxxxxx)
3807 	 * after power-up.
3808 	 */
3809 	chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
3810 
3811 	/* Send the command for reading device ID */
3812 	chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
3813 
3814 	/* Read manufacturer and device IDs */
3815 	*maf_id = chip->read_byte(mtd);
3816 	*dev_id = chip->read_byte(mtd);
3817 
3818 	/*
3819 	 * Try again to make sure, as some systems the bus-hold or other
3820 	 * interface concerns can cause random data which looks like a
3821 	 * possibly credible NAND flash to appear. If the two results do
3822 	 * not match, ignore the device completely.
3823 	 */
3824 
3825 	chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
3826 
3827 	/* Read entire ID string */
3828 	for (i = 0; i < 8; i++)
3829 		id_data[i] = chip->read_byte(mtd);
3830 
3831 	if (id_data[0] != *maf_id || id_data[1] != *dev_id) {
3832 		pr_info("second ID read did not match %02x,%02x against %02x,%02x\n",
3833 			*maf_id, *dev_id, id_data[0], id_data[1]);
3834 		return ERR_PTR(-ENODEV);
3835 	}
3836 
3837 	if (!type)
3838 		type = nand_flash_ids;
3839 
3840 	for (; type->name != NULL; type++) {
3841 		if (is_full_id_nand(type)) {
3842 			if (find_full_id_nand(mtd, chip, type, id_data, &busw))
3843 				goto ident_done;
3844 		} else if (*dev_id == type->dev_id) {
3845 			break;
3846 		}
3847 	}
3848 
3849 	chip->onfi_version = 0;
3850 	if (!type->name || !type->pagesize) {
3851 		/* Check if the chip is ONFI compliant */
3852 		if (nand_flash_detect_onfi(mtd, chip, &busw))
3853 			goto ident_done;
3854 
3855 		/* Check if the chip is JEDEC compliant */
3856 		if (nand_flash_detect_jedec(mtd, chip, &busw))
3857 			goto ident_done;
3858 	}
3859 
3860 	if (!type->name)
3861 		return ERR_PTR(-ENODEV);
3862 
3863 	if (!mtd->name)
3864 		mtd->name = type->name;
3865 
3866 	chip->chipsize = (uint64_t)type->chipsize << 20;
3867 
3868 	if (!type->pagesize) {
3869 		/* Decode parameters from extended ID */
3870 		nand_decode_ext_id(mtd, chip, id_data, &busw);
3871 	} else {
3872 		nand_decode_id(mtd, chip, type, id_data, &busw);
3873 	}
3874 	/* Get chip options */
3875 	chip->options |= type->options;
3876 
3877 	/*
3878 	 * Check if chip is not a Samsung device. Do not clear the
3879 	 * options for chips which do not have an extended id.
3880 	 */
3881 	if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
3882 		chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;
3883 ident_done:
3884 
3885 	/* Try to identify manufacturer */
3886 	for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_idx++) {
3887 		if (nand_manuf_ids[maf_idx].id == *maf_id)
3888 			break;
3889 	}
3890 
3891 	if (chip->options & NAND_BUSWIDTH_AUTO) {
3892 		WARN_ON(chip->options & NAND_BUSWIDTH_16);
3893 		chip->options |= busw;
3894 		nand_set_defaults(chip, busw);
3895 	} else if (busw != (chip->options & NAND_BUSWIDTH_16)) {
3896 		/*
3897 		 * Check, if buswidth is correct. Hardware drivers should set
3898 		 * chip correct!
3899 		 */
3900 		pr_info("device found, Manufacturer ID: 0x%02x, Chip ID: 0x%02x\n",
3901 			*maf_id, *dev_id);
3902 		pr_info("%s %s\n", nand_manuf_ids[maf_idx].name, mtd->name);
3903 		pr_warn("bus width %d instead %d bit\n",
3904 			   (chip->options & NAND_BUSWIDTH_16) ? 16 : 8,
3905 			   busw ? 16 : 8);
3906 		return ERR_PTR(-EINVAL);
3907 	}
3908 
3909 	nand_decode_bbm_options(mtd, chip, id_data);
3910 
3911 	/* Calculate the address shift from the page size */
3912 	chip->page_shift = ffs(mtd->writesize) - 1;
3913 	/* Convert chipsize to number of pages per chip -1 */
3914 	chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
3915 
3916 	chip->bbt_erase_shift = chip->phys_erase_shift =
3917 		ffs(mtd->erasesize) - 1;
3918 	if (chip->chipsize & 0xffffffff)
3919 		chip->chip_shift = ffs((unsigned)chip->chipsize) - 1;
3920 	else {
3921 		chip->chip_shift = ffs((unsigned)(chip->chipsize >> 32));
3922 		chip->chip_shift += 32 - 1;
3923 	}
3924 
3925 	chip->badblockbits = 8;
3926 	chip->erase = single_erase;
3927 
3928 	/* Do not replace user supplied command function! */
3929 	if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
3930 		chip->cmdfunc = nand_command_lp;
3931 
3932 	pr_info("device found, Manufacturer ID: 0x%02x, Chip ID: 0x%02x\n",
3933 		*maf_id, *dev_id);
3934 
3935 	if (chip->onfi_version)
3936 		pr_info("%s %s\n", nand_manuf_ids[maf_idx].name,
3937 				chip->onfi_params.model);
3938 	else if (chip->jedec_version)
3939 		pr_info("%s %s\n", nand_manuf_ids[maf_idx].name,
3940 				chip->jedec_params.model);
3941 	else
3942 		pr_info("%s %s\n", nand_manuf_ids[maf_idx].name,
3943 				type->name);
3944 
3945 	pr_info("%d MiB, %s, erase size: %d KiB, page size: %d, OOB size: %d\n",
3946 		(int)(chip->chipsize >> 20), nand_is_slc(chip) ? "SLC" : "MLC",
3947 		mtd->erasesize >> 10, mtd->writesize, mtd->oobsize);
3948 	return type;
3949 }
3950 
nand_dt_init(struct mtd_info * mtd,struct nand_chip * chip,struct device_node * dn)3951 static int nand_dt_init(struct mtd_info *mtd, struct nand_chip *chip,
3952 			struct device_node *dn)
3953 {
3954 	int ecc_mode, ecc_strength, ecc_step;
3955 
3956 	if (of_get_nand_bus_width(dn) == 16)
3957 		chip->options |= NAND_BUSWIDTH_16;
3958 
3959 	if (of_get_nand_on_flash_bbt(dn))
3960 		chip->bbt_options |= NAND_BBT_USE_FLASH;
3961 
3962 	ecc_mode = of_get_nand_ecc_mode(dn);
3963 	ecc_strength = of_get_nand_ecc_strength(dn);
3964 	ecc_step = of_get_nand_ecc_step_size(dn);
3965 
3966 	if ((ecc_step >= 0 && !(ecc_strength >= 0)) ||
3967 	    (!(ecc_step >= 0) && ecc_strength >= 0)) {
3968 		pr_err("must set both strength and step size in DT\n");
3969 		return -EINVAL;
3970 	}
3971 
3972 	if (ecc_mode >= 0)
3973 		chip->ecc.mode = ecc_mode;
3974 
3975 	if (ecc_strength >= 0)
3976 		chip->ecc.strength = ecc_strength;
3977 
3978 	if (ecc_step > 0)
3979 		chip->ecc.size = ecc_step;
3980 
3981 	return 0;
3982 }
3983 
3984 /**
3985  * nand_scan_ident - [NAND Interface] Scan for the NAND device
3986  * @mtd: MTD device structure
3987  * @maxchips: number of chips to scan for
3988  * @table: alternative NAND ID table
3989  *
3990  * This is the first phase of the normal nand_scan() function. It reads the
3991  * flash ID and sets up MTD fields accordingly.
3992  *
3993  */
nand_scan_ident(struct mtd_info * mtd,int maxchips,struct nand_flash_dev * table)3994 int nand_scan_ident(struct mtd_info *mtd, int maxchips,
3995 		    struct nand_flash_dev *table)
3996 {
3997 	int i, nand_maf_id, nand_dev_id;
3998 	struct nand_chip *chip = mtd->priv;
3999 	struct nand_flash_dev *type;
4000 	int ret;
4001 
4002 	if (chip->flash_node) {
4003 		ret = nand_dt_init(mtd, chip, chip->flash_node);
4004 		if (ret)
4005 			return ret;
4006 	}
4007 
4008 	if (!mtd->name && mtd->dev.parent)
4009 		mtd->name = dev_name(mtd->dev.parent);
4010 
4011 	/* Set the default functions */
4012 	nand_set_defaults(chip, chip->options & NAND_BUSWIDTH_16);
4013 
4014 	/* Read the flash type */
4015 	type = nand_get_flash_type(mtd, chip, &nand_maf_id,
4016 				   &nand_dev_id, table);
4017 
4018 	if (IS_ERR(type)) {
4019 		if (!(chip->options & NAND_SCAN_SILENT_NODEV))
4020 			pr_warn("No NAND device found\n");
4021 		chip->select_chip(mtd, -1);
4022 		return PTR_ERR(type);
4023 	}
4024 
4025 	chip->select_chip(mtd, -1);
4026 
4027 	/* Check for a chip array */
4028 	for (i = 1; i < maxchips; i++) {
4029 		chip->select_chip(mtd, i);
4030 		/* See comment in nand_get_flash_type for reset */
4031 		chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
4032 		/* Send the command for reading device ID */
4033 		chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
4034 		/* Read manufacturer and device IDs */
4035 		if (nand_maf_id != chip->read_byte(mtd) ||
4036 		    nand_dev_id != chip->read_byte(mtd)) {
4037 			chip->select_chip(mtd, -1);
4038 			break;
4039 		}
4040 		chip->select_chip(mtd, -1);
4041 	}
4042 	if (i > 1)
4043 		pr_info("%d chips detected\n", i);
4044 
4045 	/* Store the number of chips and calc total size for mtd */
4046 	chip->numchips = i;
4047 	mtd->size = i * chip->chipsize;
4048 
4049 	return 0;
4050 }
4051 EXPORT_SYMBOL(nand_scan_ident);
4052 
4053 /*
4054  * Check if the chip configuration meet the datasheet requirements.
4055 
4056  * If our configuration corrects A bits per B bytes and the minimum
4057  * required correction level is X bits per Y bytes, then we must ensure
4058  * both of the following are true:
4059  *
4060  * (1) A / B >= X / Y
4061  * (2) A >= X
4062  *
4063  * Requirement (1) ensures we can correct for the required bitflip density.
4064  * Requirement (2) ensures we can correct even when all bitflips are clumped
4065  * in the same sector.
4066  */
nand_ecc_strength_good(struct mtd_info * mtd)4067 static bool nand_ecc_strength_good(struct mtd_info *mtd)
4068 {
4069 	struct nand_chip *chip = mtd->priv;
4070 	struct nand_ecc_ctrl *ecc = &chip->ecc;
4071 	int corr, ds_corr;
4072 
4073 	if (ecc->size == 0 || chip->ecc_step_ds == 0)
4074 		/* Not enough information */
4075 		return true;
4076 
4077 	/*
4078 	 * We get the number of corrected bits per page to compare
4079 	 * the correction density.
4080 	 */
4081 	corr = (mtd->writesize * ecc->strength) / ecc->size;
4082 	ds_corr = (mtd->writesize * chip->ecc_strength_ds) / chip->ecc_step_ds;
4083 
4084 	return corr >= ds_corr && ecc->strength >= chip->ecc_strength_ds;
4085 }
4086 
4087 /**
4088  * nand_scan_tail - [NAND Interface] Scan for the NAND device
4089  * @mtd: MTD device structure
4090  *
4091  * This is the second phase of the normal nand_scan() function. It fills out
4092  * all the uninitialized function pointers with the defaults and scans for a
4093  * bad block table if appropriate.
4094  */
nand_scan_tail(struct mtd_info * mtd)4095 int nand_scan_tail(struct mtd_info *mtd)
4096 {
4097 	int i;
4098 	struct nand_chip *chip = mtd->priv;
4099 	struct nand_ecc_ctrl *ecc = &chip->ecc;
4100 	struct nand_buffers *nbuf;
4101 
4102 	/* New bad blocks should be marked in OOB, flash-based BBT, or both */
4103 	BUG_ON((chip->bbt_options & NAND_BBT_NO_OOB_BBM) &&
4104 			!(chip->bbt_options & NAND_BBT_USE_FLASH));
4105 
4106 	if (!(chip->options & NAND_OWN_BUFFERS)) {
4107 		nbuf = kzalloc(sizeof(*nbuf) + mtd->writesize
4108 				+ mtd->oobsize * 3, GFP_KERNEL);
4109 		if (!nbuf)
4110 			return -ENOMEM;
4111 		nbuf->ecccalc = (uint8_t *)(nbuf + 1);
4112 		nbuf->ecccode = nbuf->ecccalc + mtd->oobsize;
4113 		nbuf->databuf = nbuf->ecccode + mtd->oobsize;
4114 
4115 		chip->buffers = nbuf;
4116 	} else {
4117 		if (!chip->buffers)
4118 			return -ENOMEM;
4119 	}
4120 
4121 	/* Set the internal oob buffer location, just after the page data */
4122 	chip->oob_poi = chip->buffers->databuf + mtd->writesize;
4123 
4124 	/*
4125 	 * If no default placement scheme is given, select an appropriate one.
4126 	 */
4127 	if (!ecc->layout && (ecc->mode != NAND_ECC_SOFT_BCH)) {
4128 		switch (mtd->oobsize) {
4129 		case 8:
4130 			ecc->layout = &nand_oob_8;
4131 			break;
4132 		case 16:
4133 			ecc->layout = &nand_oob_16;
4134 			break;
4135 		case 64:
4136 			ecc->layout = &nand_oob_64;
4137 			break;
4138 		case 128:
4139 			ecc->layout = &nand_oob_128;
4140 			break;
4141 		default:
4142 			pr_warn("No oob scheme defined for oobsize %d\n",
4143 				   mtd->oobsize);
4144 			BUG();
4145 		}
4146 	}
4147 
4148 	if (!chip->write_page)
4149 		chip->write_page = nand_write_page;
4150 
4151 	/*
4152 	 * Check ECC mode, default to software if 3byte/512byte hardware ECC is
4153 	 * selected and we have 256 byte pagesize fallback to software ECC
4154 	 */
4155 
4156 	switch (ecc->mode) {
4157 	case NAND_ECC_HW_OOB_FIRST:
4158 		/* Similar to NAND_ECC_HW, but a separate read_page handle */
4159 		if (!ecc->calculate || !ecc->correct || !ecc->hwctl) {
4160 			pr_warn("No ECC functions supplied; hardware ECC not possible\n");
4161 			BUG();
4162 		}
4163 		if (!ecc->read_page)
4164 			ecc->read_page = nand_read_page_hwecc_oob_first;
4165 
4166 	case NAND_ECC_HW:
4167 		/* Use standard hwecc read page function? */
4168 		if (!ecc->read_page)
4169 			ecc->read_page = nand_read_page_hwecc;
4170 		if (!ecc->write_page)
4171 			ecc->write_page = nand_write_page_hwecc;
4172 		if (!ecc->read_page_raw)
4173 			ecc->read_page_raw = nand_read_page_raw;
4174 		if (!ecc->write_page_raw)
4175 			ecc->write_page_raw = nand_write_page_raw;
4176 		if (!ecc->read_oob)
4177 			ecc->read_oob = nand_read_oob_std;
4178 		if (!ecc->write_oob)
4179 			ecc->write_oob = nand_write_oob_std;
4180 		if (!ecc->read_subpage)
4181 			ecc->read_subpage = nand_read_subpage;
4182 		if (!ecc->write_subpage)
4183 			ecc->write_subpage = nand_write_subpage_hwecc;
4184 
4185 	case NAND_ECC_HW_SYNDROME:
4186 		if ((!ecc->calculate || !ecc->correct || !ecc->hwctl) &&
4187 		    (!ecc->read_page ||
4188 		     ecc->read_page == nand_read_page_hwecc ||
4189 		     !ecc->write_page ||
4190 		     ecc->write_page == nand_write_page_hwecc)) {
4191 			pr_warn("No ECC functions supplied; hardware ECC not possible\n");
4192 			BUG();
4193 		}
4194 		/* Use standard syndrome read/write page function? */
4195 		if (!ecc->read_page)
4196 			ecc->read_page = nand_read_page_syndrome;
4197 		if (!ecc->write_page)
4198 			ecc->write_page = nand_write_page_syndrome;
4199 		if (!ecc->read_page_raw)
4200 			ecc->read_page_raw = nand_read_page_raw_syndrome;
4201 		if (!ecc->write_page_raw)
4202 			ecc->write_page_raw = nand_write_page_raw_syndrome;
4203 		if (!ecc->read_oob)
4204 			ecc->read_oob = nand_read_oob_syndrome;
4205 		if (!ecc->write_oob)
4206 			ecc->write_oob = nand_write_oob_syndrome;
4207 
4208 		if (mtd->writesize >= ecc->size) {
4209 			if (!ecc->strength) {
4210 				pr_warn("Driver must set ecc.strength when using hardware ECC\n");
4211 				BUG();
4212 			}
4213 			break;
4214 		}
4215 		pr_warn("%d byte HW ECC not possible on %d byte page size, fallback to SW ECC\n",
4216 			ecc->size, mtd->writesize);
4217 		ecc->mode = NAND_ECC_SOFT;
4218 
4219 	case NAND_ECC_SOFT:
4220 		ecc->calculate = nand_calculate_ecc;
4221 		ecc->correct = nand_correct_data;
4222 		ecc->read_page = nand_read_page_swecc;
4223 		ecc->read_subpage = nand_read_subpage;
4224 		ecc->write_page = nand_write_page_swecc;
4225 		ecc->read_page_raw = nand_read_page_raw;
4226 		ecc->write_page_raw = nand_write_page_raw;
4227 		ecc->read_oob = nand_read_oob_std;
4228 		ecc->write_oob = nand_write_oob_std;
4229 		if (!ecc->size)
4230 			ecc->size = 256;
4231 		ecc->bytes = 3;
4232 		ecc->strength = 1;
4233 		break;
4234 
4235 	case NAND_ECC_SOFT_BCH:
4236 		if (!mtd_nand_has_bch()) {
4237 			pr_warn("CONFIG_MTD_NAND_ECC_BCH not enabled\n");
4238 			BUG();
4239 		}
4240 		ecc->calculate = nand_bch_calculate_ecc;
4241 		ecc->correct = nand_bch_correct_data;
4242 		ecc->read_page = nand_read_page_swecc;
4243 		ecc->read_subpage = nand_read_subpage;
4244 		ecc->write_page = nand_write_page_swecc;
4245 		ecc->read_page_raw = nand_read_page_raw;
4246 		ecc->write_page_raw = nand_write_page_raw;
4247 		ecc->read_oob = nand_read_oob_std;
4248 		ecc->write_oob = nand_write_oob_std;
4249 		/*
4250 		 * Board driver should supply ecc.size and ecc.strength values
4251 		 * to select how many bits are correctable. Otherwise, default
4252 		 * to 4 bits for large page devices.
4253 		 */
4254 		if (!ecc->size && (mtd->oobsize >= 64)) {
4255 			ecc->size = 512;
4256 			ecc->strength = 4;
4257 		}
4258 
4259 		/* See nand_bch_init() for details. */
4260 		ecc->bytes = DIV_ROUND_UP(
4261 				ecc->strength * fls(8 * ecc->size), 8);
4262 		ecc->priv = nand_bch_init(mtd, ecc->size, ecc->bytes,
4263 					       &ecc->layout);
4264 		if (!ecc->priv) {
4265 			pr_warn("BCH ECC initialization failed!\n");
4266 			BUG();
4267 		}
4268 		break;
4269 
4270 	case NAND_ECC_NONE:
4271 		pr_warn("NAND_ECC_NONE selected by board driver. This is not recommended!\n");
4272 		ecc->read_page = nand_read_page_raw;
4273 		ecc->write_page = nand_write_page_raw;
4274 		ecc->read_oob = nand_read_oob_std;
4275 		ecc->read_page_raw = nand_read_page_raw;
4276 		ecc->write_page_raw = nand_write_page_raw;
4277 		ecc->write_oob = nand_write_oob_std;
4278 		ecc->size = mtd->writesize;
4279 		ecc->bytes = 0;
4280 		ecc->strength = 0;
4281 		break;
4282 
4283 	default:
4284 		pr_warn("Invalid NAND_ECC_MODE %d\n", ecc->mode);
4285 		BUG();
4286 	}
4287 
4288 	/* For many systems, the standard OOB write also works for raw */
4289 	if (!ecc->read_oob_raw)
4290 		ecc->read_oob_raw = ecc->read_oob;
4291 	if (!ecc->write_oob_raw)
4292 		ecc->write_oob_raw = ecc->write_oob;
4293 
4294 	/*
4295 	 * The number of bytes available for a client to place data into
4296 	 * the out of band area.
4297 	 */
4298 	ecc->layout->oobavail = 0;
4299 	for (i = 0; ecc->layout->oobfree[i].length
4300 			&& i < ARRAY_SIZE(ecc->layout->oobfree); i++)
4301 		ecc->layout->oobavail += ecc->layout->oobfree[i].length;
4302 	mtd->oobavail = ecc->layout->oobavail;
4303 
4304 	/* ECC sanity check: warn if it's too weak */
4305 	if (!nand_ecc_strength_good(mtd))
4306 		pr_warn("WARNING: %s: the ECC used on your system is too weak compared to the one required by the NAND chip\n",
4307 			mtd->name);
4308 
4309 	/*
4310 	 * Set the number of read / write steps for one page depending on ECC
4311 	 * mode.
4312 	 */
4313 	ecc->steps = mtd->writesize / ecc->size;
4314 	if (ecc->steps * ecc->size != mtd->writesize) {
4315 		pr_warn("Invalid ECC parameters\n");
4316 		BUG();
4317 	}
4318 	ecc->total = ecc->steps * ecc->bytes;
4319 
4320 	/* Allow subpage writes up to ecc.steps. Not possible for MLC flash */
4321 	if (!(chip->options & NAND_NO_SUBPAGE_WRITE) && nand_is_slc(chip)) {
4322 		switch (ecc->steps) {
4323 		case 2:
4324 			mtd->subpage_sft = 1;
4325 			break;
4326 		case 4:
4327 		case 8:
4328 		case 16:
4329 			mtd->subpage_sft = 2;
4330 			break;
4331 		}
4332 	}
4333 	chip->subpagesize = mtd->writesize >> mtd->subpage_sft;
4334 
4335 	/* Initialize state */
4336 	chip->state = FL_READY;
4337 
4338 	/* Invalidate the pagebuffer reference */
4339 	chip->pagebuf = -1;
4340 
4341 	/* Large page NAND with SOFT_ECC should support subpage reads */
4342 	switch (ecc->mode) {
4343 	case NAND_ECC_SOFT:
4344 	case NAND_ECC_SOFT_BCH:
4345 		if (chip->page_shift > 9)
4346 			chip->options |= NAND_SUBPAGE_READ;
4347 		break;
4348 
4349 	default:
4350 		break;
4351 	}
4352 
4353 	/* Fill in remaining MTD driver data */
4354 	mtd->type = nand_is_slc(chip) ? MTD_NANDFLASH : MTD_MLCNANDFLASH;
4355 	mtd->flags = (chip->options & NAND_ROM) ? MTD_CAP_ROM :
4356 						MTD_CAP_NANDFLASH;
4357 	mtd->_erase = nand_erase;
4358 	mtd->_point = NULL;
4359 	mtd->_unpoint = NULL;
4360 	mtd->_read = nand_read;
4361 	mtd->_write = nand_write;
4362 	mtd->_panic_write = panic_nand_write;
4363 	mtd->_read_oob = nand_read_oob;
4364 	mtd->_write_oob = nand_write_oob;
4365 	mtd->_sync = nand_sync;
4366 	mtd->_lock = NULL;
4367 	mtd->_unlock = NULL;
4368 	mtd->_suspend = nand_suspend;
4369 	mtd->_resume = nand_resume;
4370 	mtd->_reboot = nand_shutdown;
4371 	mtd->_block_isreserved = nand_block_isreserved;
4372 	mtd->_block_isbad = nand_block_isbad;
4373 	mtd->_block_markbad = nand_block_markbad;
4374 	mtd->writebufsize = mtd->writesize;
4375 
4376 	/* propagate ecc info to mtd_info */
4377 	mtd->ecclayout = ecc->layout;
4378 	mtd->ecc_strength = ecc->strength;
4379 	mtd->ecc_step_size = ecc->size;
4380 	/*
4381 	 * Initialize bitflip_threshold to its default prior scan_bbt() call.
4382 	 * scan_bbt() might invoke mtd_read(), thus bitflip_threshold must be
4383 	 * properly set.
4384 	 */
4385 	if (!mtd->bitflip_threshold)
4386 		mtd->bitflip_threshold = DIV_ROUND_UP(mtd->ecc_strength * 3, 4);
4387 
4388 	/* Check, if we should skip the bad block table scan */
4389 	if (chip->options & NAND_SKIP_BBTSCAN)
4390 		return 0;
4391 
4392 	/* Build bad block table */
4393 	return chip->scan_bbt(mtd);
4394 }
4395 EXPORT_SYMBOL(nand_scan_tail);
4396 
4397 /*
4398  * is_module_text_address() isn't exported, and it's mostly a pointless
4399  * test if this is a module _anyway_ -- they'd have to try _really_ hard
4400  * to call us from in-kernel code if the core NAND support is modular.
4401  */
4402 #ifdef MODULE
4403 #define caller_is_module() (1)
4404 #else
4405 #define caller_is_module() \
4406 	is_module_text_address((unsigned long)__builtin_return_address(0))
4407 #endif
4408 
4409 /**
4410  * nand_scan - [NAND Interface] Scan for the NAND device
4411  * @mtd: MTD device structure
4412  * @maxchips: number of chips to scan for
4413  *
4414  * This fills out all the uninitialized function pointers with the defaults.
4415  * The flash ID is read and the mtd/chip structures are filled with the
4416  * appropriate values.
4417  */
nand_scan(struct mtd_info * mtd,int maxchips)4418 int nand_scan(struct mtd_info *mtd, int maxchips)
4419 {
4420 	int ret;
4421 
4422 	ret = nand_scan_ident(mtd, maxchips, NULL);
4423 	if (!ret)
4424 		ret = nand_scan_tail(mtd);
4425 	return ret;
4426 }
4427 EXPORT_SYMBOL(nand_scan);
4428 
4429 /**
4430  * nand_cleanup - [NAND Interface] Free resources held by the NAND device
4431  * @chip: NAND chip object
4432  */
nand_cleanup(struct nand_chip * chip)4433 void nand_cleanup(struct nand_chip *chip)
4434 {
4435 	if (chip->ecc.mode == NAND_ECC_SOFT_BCH)
4436 		nand_bch_free((struct nand_bch_control *)chip->ecc.priv);
4437 
4438 	/* Free bad block table memory */
4439 	kfree(chip->bbt);
4440 	if (!(chip->options & NAND_OWN_BUFFERS))
4441 		kfree(chip->buffers);
4442 
4443 	/* Free bad block descriptor memory */
4444 	if (chip->badblock_pattern && chip->badblock_pattern->options
4445 			& NAND_BBT_DYNAMICSTRUCT)
4446 		kfree(chip->badblock_pattern);
4447 }
4448 EXPORT_SYMBOL_GPL(nand_cleanup);
4449 
4450 /**
4451  * nand_release - [NAND Interface] Unregister the MTD device and free resources
4452  *		  held by the NAND device
4453  * @mtd: MTD device structure
4454  */
nand_release(struct mtd_info * mtd)4455 void nand_release(struct mtd_info *mtd)
4456 {
4457 	mtd_device_unregister(mtd);
4458 	nand_cleanup(mtd->priv);
4459 }
4460 EXPORT_SYMBOL_GPL(nand_release);
4461 
nand_base_init(void)4462 static int __init nand_base_init(void)
4463 {
4464 	led_trigger_register_simple("nand-disk", &nand_led_trigger);
4465 	return 0;
4466 }
4467 
nand_base_exit(void)4468 static void __exit nand_base_exit(void)
4469 {
4470 	led_trigger_unregister_simple(nand_led_trigger);
4471 }
4472 
4473 module_init(nand_base_init);
4474 module_exit(nand_base_exit);
4475 
4476 MODULE_LICENSE("GPL");
4477 MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>");
4478 MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");
4479 MODULE_DESCRIPTION("Generic NAND flash driver code");
4480