xref: /linux/drivers/mtd/devices/docg3.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  * Handles the M-Systems DiskOnChip G3 chip
3  *
4  * Copyright (C) 2011 Robert Jarzmik
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  *
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/platform_device.h>
26 #include <linux/string.h>
27 #include <linux/slab.h>
28 #include <linux/io.h>
29 #include <linux/delay.h>
30 #include <linux/mtd/mtd.h>
31 #include <linux/mtd/partitions.h>
32 #include <linux/bitmap.h>
33 #include <linux/bitrev.h>
34 #include <linux/bch.h>
35 
36 #include <linux/debugfs.h>
37 #include <linux/seq_file.h>
38 
39 #define CREATE_TRACE_POINTS
40 #include "docg3.h"
41 
42 /*
43  * This driver handles the DiskOnChip G3 flash memory.
44  *
45  * As no specification is available from M-Systems/Sandisk, this drivers lacks
46  * several functions available on the chip, as :
47  *  - IPL write
48  *
49  * The bus data width (8bits versus 16bits) is not handled (if_cfg flag), and
50  * the driver assumes a 16bits data bus.
51  *
52  * DocG3 relies on 2 ECC algorithms, which are handled in hardware :
53  *  - a 1 byte Hamming code stored in the OOB for each page
54  *  - a 7 bytes BCH code stored in the OOB for each page
55  * The BCH ECC is :
56  *  - BCH is in GF(2^14)
57  *  - BCH is over data of 520 bytes (512 page + 7 page_info bytes
58  *                                   + 1 hamming byte)
59  *  - BCH can correct up to 4 bits (t = 4)
60  *  - BCH syndroms are calculated in hardware, and checked in hardware as well
61  *
62  */
63 
64 static unsigned int reliable_mode;
65 module_param(reliable_mode, uint, 0);
66 MODULE_PARM_DESC(reliable_mode, "Set the docg3 mode (0=normal MLC, 1=fast, "
67 		 "2=reliable) : MLC normal operations are in normal mode");
68 
69 /**
70  * struct docg3_oobinfo - DiskOnChip G3 OOB layout
71  * @eccbytes: 8 bytes are used (1 for Hamming ECC, 7 for BCH ECC)
72  * @eccpos: ecc positions (byte 7 is Hamming ECC, byte 8-14 are BCH ECC)
73  * @oobfree: free pageinfo bytes (byte 0 until byte 6, byte 15
74  * @oobavail: 8 available bytes remaining after ECC toll
75  */
76 static struct nand_ecclayout docg3_oobinfo = {
77 	.eccbytes = 8,
78 	.eccpos = {7, 8, 9, 10, 11, 12, 13, 14},
79 	.oobfree = {{0, 7}, {15, 1} },
80 	.oobavail = 8,
81 };
82 
83 /**
84  * struct docg3_bch - BCH engine
85  */
86 static struct bch_control *docg3_bch;
87 
88 static inline u8 doc_readb(struct docg3 *docg3, u16 reg)
89 {
90 	u8 val = readb(docg3->base + reg);
91 
92 	trace_docg3_io(0, 8, reg, (int)val);
93 	return val;
94 }
95 
96 static inline u16 doc_readw(struct docg3 *docg3, u16 reg)
97 {
98 	u16 val = readw(docg3->base + reg);
99 
100 	trace_docg3_io(0, 16, reg, (int)val);
101 	return val;
102 }
103 
104 static inline void doc_writeb(struct docg3 *docg3, u8 val, u16 reg)
105 {
106 	writeb(val, docg3->base + reg);
107 	trace_docg3_io(1, 8, reg, val);
108 }
109 
110 static inline void doc_writew(struct docg3 *docg3, u16 val, u16 reg)
111 {
112 	writew(val, docg3->base + reg);
113 	trace_docg3_io(1, 16, reg, val);
114 }
115 
116 static inline void doc_flash_command(struct docg3 *docg3, u8 cmd)
117 {
118 	doc_writeb(docg3, cmd, DOC_FLASHCOMMAND);
119 }
120 
121 static inline void doc_flash_sequence(struct docg3 *docg3, u8 seq)
122 {
123 	doc_writeb(docg3, seq, DOC_FLASHSEQUENCE);
124 }
125 
126 static inline void doc_flash_address(struct docg3 *docg3, u8 addr)
127 {
128 	doc_writeb(docg3, addr, DOC_FLASHADDRESS);
129 }
130 
131 static char const *part_probes[] = { "cmdlinepart", "saftlpart", NULL };
132 
133 static int doc_register_readb(struct docg3 *docg3, int reg)
134 {
135 	u8 val;
136 
137 	doc_writew(docg3, reg, DOC_READADDRESS);
138 	val = doc_readb(docg3, reg);
139 	doc_vdbg("Read register %04x : %02x\n", reg, val);
140 	return val;
141 }
142 
143 static int doc_register_readw(struct docg3 *docg3, int reg)
144 {
145 	u16 val;
146 
147 	doc_writew(docg3, reg, DOC_READADDRESS);
148 	val = doc_readw(docg3, reg);
149 	doc_vdbg("Read register %04x : %04x\n", reg, val);
150 	return val;
151 }
152 
153 /**
154  * doc_delay - delay docg3 operations
155  * @docg3: the device
156  * @nbNOPs: the number of NOPs to issue
157  *
158  * As no specification is available, the right timings between chip commands are
159  * unknown. The only available piece of information are the observed nops on a
160  * working docg3 chip.
161  * Therefore, doc_delay relies on a busy loop of NOPs, instead of scheduler
162  * friendlier msleep() functions or blocking mdelay().
163  */
164 static void doc_delay(struct docg3 *docg3, int nbNOPs)
165 {
166 	int i;
167 
168 	doc_vdbg("NOP x %d\n", nbNOPs);
169 	for (i = 0; i < nbNOPs; i++)
170 		doc_writeb(docg3, 0, DOC_NOP);
171 }
172 
173 static int is_prot_seq_error(struct docg3 *docg3)
174 {
175 	int ctrl;
176 
177 	ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
178 	return ctrl & (DOC_CTRL_PROTECTION_ERROR | DOC_CTRL_SEQUENCE_ERROR);
179 }
180 
181 static int doc_is_ready(struct docg3 *docg3)
182 {
183 	int ctrl;
184 
185 	ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
186 	return ctrl & DOC_CTRL_FLASHREADY;
187 }
188 
189 static int doc_wait_ready(struct docg3 *docg3)
190 {
191 	int maxWaitCycles = 100;
192 
193 	do {
194 		doc_delay(docg3, 4);
195 		cpu_relax();
196 	} while (!doc_is_ready(docg3) && maxWaitCycles--);
197 	doc_delay(docg3, 2);
198 	if (maxWaitCycles > 0)
199 		return 0;
200 	else
201 		return -EIO;
202 }
203 
204 static int doc_reset_seq(struct docg3 *docg3)
205 {
206 	int ret;
207 
208 	doc_writeb(docg3, 0x10, DOC_FLASHCONTROL);
209 	doc_flash_sequence(docg3, DOC_SEQ_RESET);
210 	doc_flash_command(docg3, DOC_CMD_RESET);
211 	doc_delay(docg3, 2);
212 	ret = doc_wait_ready(docg3);
213 
214 	doc_dbg("doc_reset_seq() -> isReady=%s\n", ret ? "false" : "true");
215 	return ret;
216 }
217 
218 /**
219  * doc_read_data_area - Read data from data area
220  * @docg3: the device
221  * @buf: the buffer to fill in (might be NULL is dummy reads)
222  * @len: the length to read
223  * @first: first time read, DOC_READADDRESS should be set
224  *
225  * Reads bytes from flash data. Handles the single byte / even bytes reads.
226  */
227 static void doc_read_data_area(struct docg3 *docg3, void *buf, int len,
228 			       int first)
229 {
230 	int i, cdr, len4;
231 	u16 data16, *dst16;
232 	u8 data8, *dst8;
233 
234 	doc_dbg("doc_read_data_area(buf=%p, len=%d)\n", buf, len);
235 	cdr = len & 0x3;
236 	len4 = len - cdr;
237 
238 	if (first)
239 		doc_writew(docg3, DOC_IOSPACE_DATA, DOC_READADDRESS);
240 	dst16 = buf;
241 	for (i = 0; i < len4; i += 2) {
242 		data16 = doc_readw(docg3, DOC_IOSPACE_DATA);
243 		if (dst16) {
244 			*dst16 = data16;
245 			dst16++;
246 		}
247 	}
248 
249 	if (cdr) {
250 		doc_writew(docg3, DOC_IOSPACE_DATA | DOC_READADDR_ONE_BYTE,
251 			   DOC_READADDRESS);
252 		doc_delay(docg3, 1);
253 		dst8 = (u8 *)dst16;
254 		for (i = 0; i < cdr; i++) {
255 			data8 = doc_readb(docg3, DOC_IOSPACE_DATA);
256 			if (dst8) {
257 				*dst8 = data8;
258 				dst8++;
259 			}
260 		}
261 	}
262 }
263 
264 /**
265  * doc_write_data_area - Write data into data area
266  * @docg3: the device
267  * @buf: the buffer to get input bytes from
268  * @len: the length to write
269  *
270  * Writes bytes into flash data. Handles the single byte / even bytes writes.
271  */
272 static void doc_write_data_area(struct docg3 *docg3, const void *buf, int len)
273 {
274 	int i, cdr, len4;
275 	u16 *src16;
276 	u8 *src8;
277 
278 	doc_dbg("doc_write_data_area(buf=%p, len=%d)\n", buf, len);
279 	cdr = len & 0x3;
280 	len4 = len - cdr;
281 
282 	doc_writew(docg3, DOC_IOSPACE_DATA, DOC_READADDRESS);
283 	src16 = (u16 *)buf;
284 	for (i = 0; i < len4; i += 2) {
285 		doc_writew(docg3, *src16, DOC_IOSPACE_DATA);
286 		src16++;
287 	}
288 
289 	src8 = (u8 *)src16;
290 	for (i = 0; i < cdr; i++) {
291 		doc_writew(docg3, DOC_IOSPACE_DATA | DOC_READADDR_ONE_BYTE,
292 			   DOC_READADDRESS);
293 		doc_writeb(docg3, *src8, DOC_IOSPACE_DATA);
294 		src8++;
295 	}
296 }
297 
298 /**
299  * doc_set_data_mode - Sets the flash to normal or reliable data mode
300  * @docg3: the device
301  *
302  * The reliable data mode is a bit slower than the fast mode, but less errors
303  * occur.  Entering the reliable mode cannot be done without entering the fast
304  * mode first.
305  *
306  * In reliable mode, pages 2*n and 2*n+1 are clones. Writing to page 0 of blocks
307  * (4,5) make the hardware write also to page 1 of blocks blocks(4,5). Reading
308  * from page 0 of blocks (4,5) or from page 1 of blocks (4,5) gives the same
309  * result, which is a logical and between bytes from page 0 and page 1 (which is
310  * consistent with the fact that writing to a page is _clearing_ bits of that
311  * page).
312  */
313 static void doc_set_reliable_mode(struct docg3 *docg3)
314 {
315 	static char *strmode[] = { "normal", "fast", "reliable", "invalid" };
316 
317 	doc_dbg("doc_set_reliable_mode(%s)\n", strmode[docg3->reliable]);
318 	switch (docg3->reliable) {
319 	case 0:
320 		break;
321 	case 1:
322 		doc_flash_sequence(docg3, DOC_SEQ_SET_FASTMODE);
323 		doc_flash_command(docg3, DOC_CMD_FAST_MODE);
324 		break;
325 	case 2:
326 		doc_flash_sequence(docg3, DOC_SEQ_SET_RELIABLEMODE);
327 		doc_flash_command(docg3, DOC_CMD_FAST_MODE);
328 		doc_flash_command(docg3, DOC_CMD_RELIABLE_MODE);
329 		break;
330 	default:
331 		doc_err("doc_set_reliable_mode(): invalid mode\n");
332 		break;
333 	}
334 	doc_delay(docg3, 2);
335 }
336 
337 /**
338  * doc_set_asic_mode - Set the ASIC mode
339  * @docg3: the device
340  * @mode: the mode
341  *
342  * The ASIC can work in 3 modes :
343  *  - RESET: all registers are zeroed
344  *  - NORMAL: receives and handles commands
345  *  - POWERDOWN: minimal poweruse, flash parts shut off
346  */
347 static void doc_set_asic_mode(struct docg3 *docg3, u8 mode)
348 {
349 	int i;
350 
351 	for (i = 0; i < 12; i++)
352 		doc_readb(docg3, DOC_IOSPACE_IPL);
353 
354 	mode |= DOC_ASICMODE_MDWREN;
355 	doc_dbg("doc_set_asic_mode(%02x)\n", mode);
356 	doc_writeb(docg3, mode, DOC_ASICMODE);
357 	doc_writeb(docg3, ~mode, DOC_ASICMODECONFIRM);
358 	doc_delay(docg3, 1);
359 }
360 
361 /**
362  * doc_set_device_id - Sets the devices id for cascaded G3 chips
363  * @docg3: the device
364  * @id: the chip to select (amongst 0, 1, 2, 3)
365  *
366  * There can be 4 cascaded G3 chips. This function selects the one which will
367  * should be the active one.
368  */
369 static void doc_set_device_id(struct docg3 *docg3, int id)
370 {
371 	u8 ctrl;
372 
373 	doc_dbg("doc_set_device_id(%d)\n", id);
374 	doc_writeb(docg3, id, DOC_DEVICESELECT);
375 	ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
376 
377 	ctrl &= ~DOC_CTRL_VIOLATION;
378 	ctrl |= DOC_CTRL_CE;
379 	doc_writeb(docg3, ctrl, DOC_FLASHCONTROL);
380 }
381 
382 /**
383  * doc_set_extra_page_mode - Change flash page layout
384  * @docg3: the device
385  *
386  * Normally, the flash page is split into the data (512 bytes) and the out of
387  * band data (16 bytes). For each, 4 more bytes can be accessed, where the wear
388  * leveling counters are stored.  To access this last area of 4 bytes, a special
389  * mode must be input to the flash ASIC.
390  *
391  * Returns 0 if no error occured, -EIO else.
392  */
393 static int doc_set_extra_page_mode(struct docg3 *docg3)
394 {
395 	int fctrl;
396 
397 	doc_dbg("doc_set_extra_page_mode()\n");
398 	doc_flash_sequence(docg3, DOC_SEQ_PAGE_SIZE_532);
399 	doc_flash_command(docg3, DOC_CMD_PAGE_SIZE_532);
400 	doc_delay(docg3, 2);
401 
402 	fctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
403 	if (fctrl & (DOC_CTRL_PROTECTION_ERROR | DOC_CTRL_SEQUENCE_ERROR))
404 		return -EIO;
405 	else
406 		return 0;
407 }
408 
409 /**
410  * doc_setup_addr_sector - Setup blocks/page/ofs address for one plane
411  * @docg3: the device
412  * @sector: the sector
413  */
414 static void doc_setup_addr_sector(struct docg3 *docg3, int sector)
415 {
416 	doc_delay(docg3, 1);
417 	doc_flash_address(docg3, sector & 0xff);
418 	doc_flash_address(docg3, (sector >> 8) & 0xff);
419 	doc_flash_address(docg3, (sector >> 16) & 0xff);
420 	doc_delay(docg3, 1);
421 }
422 
423 /**
424  * doc_setup_writeaddr_sector - Setup blocks/page/ofs address for one plane
425  * @docg3: the device
426  * @sector: the sector
427  * @ofs: the offset in the page, between 0 and (512 + 16 + 512)
428  */
429 static void doc_setup_writeaddr_sector(struct docg3 *docg3, int sector, int ofs)
430 {
431 	ofs = ofs >> 2;
432 	doc_delay(docg3, 1);
433 	doc_flash_address(docg3, ofs & 0xff);
434 	doc_flash_address(docg3, sector & 0xff);
435 	doc_flash_address(docg3, (sector >> 8) & 0xff);
436 	doc_flash_address(docg3, (sector >> 16) & 0xff);
437 	doc_delay(docg3, 1);
438 }
439 
440 /**
441  * doc_seek - Set both flash planes to the specified block, page for reading
442  * @docg3: the device
443  * @block0: the first plane block index
444  * @block1: the second plane block index
445  * @page: the page index within the block
446  * @wear: if true, read will occur on the 4 extra bytes of the wear area
447  * @ofs: offset in page to read
448  *
449  * Programs the flash even and odd planes to the specific block and page.
450  * Alternatively, programs the flash to the wear area of the specified page.
451  */
452 static int doc_read_seek(struct docg3 *docg3, int block0, int block1, int page,
453 			 int wear, int ofs)
454 {
455 	int sector, ret = 0;
456 
457 	doc_dbg("doc_seek(blocks=(%d,%d), page=%d, ofs=%d, wear=%d)\n",
458 		block0, block1, page, ofs, wear);
459 
460 	if (!wear && (ofs < 2 * DOC_LAYOUT_PAGE_SIZE)) {
461 		doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE1);
462 		doc_flash_command(docg3, DOC_CMD_READ_PLANE1);
463 		doc_delay(docg3, 2);
464 	} else {
465 		doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE2);
466 		doc_flash_command(docg3, DOC_CMD_READ_PLANE2);
467 		doc_delay(docg3, 2);
468 	}
469 
470 	doc_set_reliable_mode(docg3);
471 	if (wear)
472 		ret = doc_set_extra_page_mode(docg3);
473 	if (ret)
474 		goto out;
475 
476 	doc_flash_sequence(docg3, DOC_SEQ_READ);
477 	sector = (block0 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
478 	doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
479 	doc_setup_addr_sector(docg3, sector);
480 
481 	sector = (block1 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
482 	doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
483 	doc_setup_addr_sector(docg3, sector);
484 	doc_delay(docg3, 1);
485 
486 out:
487 	return ret;
488 }
489 
490 /**
491  * doc_write_seek - Set both flash planes to the specified block, page for writing
492  * @docg3: the device
493  * @block0: the first plane block index
494  * @block1: the second plane block index
495  * @page: the page index within the block
496  * @ofs: offset in page to write
497  *
498  * Programs the flash even and odd planes to the specific block and page.
499  * Alternatively, programs the flash to the wear area of the specified page.
500  */
501 static int doc_write_seek(struct docg3 *docg3, int block0, int block1, int page,
502 			 int ofs)
503 {
504 	int ret = 0, sector;
505 
506 	doc_dbg("doc_write_seek(blocks=(%d,%d), page=%d, ofs=%d)\n",
507 		block0, block1, page, ofs);
508 
509 	doc_set_reliable_mode(docg3);
510 
511 	if (ofs < 2 * DOC_LAYOUT_PAGE_SIZE) {
512 		doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE1);
513 		doc_flash_command(docg3, DOC_CMD_READ_PLANE1);
514 		doc_delay(docg3, 2);
515 	} else {
516 		doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE2);
517 		doc_flash_command(docg3, DOC_CMD_READ_PLANE2);
518 		doc_delay(docg3, 2);
519 	}
520 
521 	doc_flash_sequence(docg3, DOC_SEQ_PAGE_SETUP);
522 	doc_flash_command(docg3, DOC_CMD_PROG_CYCLE1);
523 
524 	sector = (block0 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
525 	doc_setup_writeaddr_sector(docg3, sector, ofs);
526 
527 	doc_flash_command(docg3, DOC_CMD_PROG_CYCLE3);
528 	doc_delay(docg3, 2);
529 	ret = doc_wait_ready(docg3);
530 	if (ret)
531 		goto out;
532 
533 	doc_flash_command(docg3, DOC_CMD_PROG_CYCLE1);
534 	sector = (block1 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
535 	doc_setup_writeaddr_sector(docg3, sector, ofs);
536 	doc_delay(docg3, 1);
537 
538 out:
539 	return ret;
540 }
541 
542 
543 /**
544  * doc_read_page_ecc_init - Initialize hardware ECC engine
545  * @docg3: the device
546  * @len: the number of bytes covered by the ECC (BCH covered)
547  *
548  * The function does initialize the hardware ECC engine to compute the Hamming
549  * ECC (on 1 byte) and the BCH hardware ECC (on 7 bytes).
550  *
551  * Return 0 if succeeded, -EIO on error
552  */
553 static int doc_read_page_ecc_init(struct docg3 *docg3, int len)
554 {
555 	doc_writew(docg3, DOC_ECCCONF0_READ_MODE
556 		   | DOC_ECCCONF0_BCH_ENABLE | DOC_ECCCONF0_HAMMING_ENABLE
557 		   | (len & DOC_ECCCONF0_DATA_BYTES_MASK),
558 		   DOC_ECCCONF0);
559 	doc_delay(docg3, 4);
560 	doc_register_readb(docg3, DOC_FLASHCONTROL);
561 	return doc_wait_ready(docg3);
562 }
563 
564 /**
565  * doc_write_page_ecc_init - Initialize hardware BCH ECC engine
566  * @docg3: the device
567  * @len: the number of bytes covered by the ECC (BCH covered)
568  *
569  * The function does initialize the hardware ECC engine to compute the Hamming
570  * ECC (on 1 byte) and the BCH hardware ECC (on 7 bytes).
571  *
572  * Return 0 if succeeded, -EIO on error
573  */
574 static int doc_write_page_ecc_init(struct docg3 *docg3, int len)
575 {
576 	doc_writew(docg3, DOC_ECCCONF0_WRITE_MODE
577 		   | DOC_ECCCONF0_BCH_ENABLE | DOC_ECCCONF0_HAMMING_ENABLE
578 		   | (len & DOC_ECCCONF0_DATA_BYTES_MASK),
579 		   DOC_ECCCONF0);
580 	doc_delay(docg3, 4);
581 	doc_register_readb(docg3, DOC_FLASHCONTROL);
582 	return doc_wait_ready(docg3);
583 }
584 
585 /**
586  * doc_ecc_disable - Disable Hamming and BCH ECC hardware calculator
587  * @docg3: the device
588  *
589  * Disables the hardware ECC generator and checker, for unchecked reads (as when
590  * reading OOB only or write status byte).
591  */
592 static void doc_ecc_disable(struct docg3 *docg3)
593 {
594 	doc_writew(docg3, DOC_ECCCONF0_READ_MODE, DOC_ECCCONF0);
595 	doc_delay(docg3, 4);
596 }
597 
598 /**
599  * doc_hamming_ecc_init - Initialize hardware Hamming ECC engine
600  * @docg3: the device
601  * @nb_bytes: the number of bytes covered by the ECC (Hamming covered)
602  *
603  * This function programs the ECC hardware to compute the hamming code on the
604  * last provided N bytes to the hardware generator.
605  */
606 static void doc_hamming_ecc_init(struct docg3 *docg3, int nb_bytes)
607 {
608 	u8 ecc_conf1;
609 
610 	ecc_conf1 = doc_register_readb(docg3, DOC_ECCCONF1);
611 	ecc_conf1 &= ~DOC_ECCCONF1_HAMMING_BITS_MASK;
612 	ecc_conf1 |= (nb_bytes & DOC_ECCCONF1_HAMMING_BITS_MASK);
613 	doc_writeb(docg3, ecc_conf1, DOC_ECCCONF1);
614 }
615 
616 /**
617  * doc_ecc_bch_fix_data - Fix if need be read data from flash
618  * @docg3: the device
619  * @buf: the buffer of read data (512 + 7 + 1 bytes)
620  * @hwecc: the hardware calculated ECC.
621  *         It's in fact recv_ecc ^ calc_ecc, where recv_ecc was read from OOB
622  *         area data, and calc_ecc the ECC calculated by the hardware generator.
623  *
624  * Checks if the received data matches the ECC, and if an error is detected,
625  * tries to fix the bit flips (at most 4) in the buffer buf.  As the docg3
626  * understands the (data, ecc, syndroms) in an inverted order in comparison to
627  * the BCH library, the function reverses the order of bits (ie. bit7 and bit0,
628  * bit6 and bit 1, ...) for all ECC data.
629  *
630  * The hardware ecc unit produces oob_ecc ^ calc_ecc.  The kernel's bch
631  * algorithm is used to decode this.  However the hw operates on page
632  * data in a bit order that is the reverse of that of the bch alg,
633  * requiring that the bits be reversed on the result.  Thanks to Ivan
634  * Djelic for his analysis.
635  *
636  * Returns number of fixed bits (0, 1, 2, 3, 4) or -EBADMSG if too many bit
637  * errors were detected and cannot be fixed.
638  */
639 static int doc_ecc_bch_fix_data(struct docg3 *docg3, void *buf, u8 *hwecc)
640 {
641 	u8 ecc[DOC_ECC_BCH_SIZE];
642 	int errorpos[DOC_ECC_BCH_T], i, numerrs;
643 
644 	for (i = 0; i < DOC_ECC_BCH_SIZE; i++)
645 		ecc[i] = bitrev8(hwecc[i]);
646 	numerrs = decode_bch(docg3_bch, NULL, DOC_ECC_BCH_COVERED_BYTES,
647 			     NULL, ecc, NULL, errorpos);
648 	BUG_ON(numerrs == -EINVAL);
649 	if (numerrs < 0)
650 		goto out;
651 
652 	for (i = 0; i < numerrs; i++)
653 		errorpos[i] = (errorpos[i] & ~7) | (7 - (errorpos[i] & 7));
654 	for (i = 0; i < numerrs; i++)
655 		if (errorpos[i] < DOC_ECC_BCH_COVERED_BYTES*8)
656 			/* error is located in data, correct it */
657 			change_bit(errorpos[i], buf);
658 out:
659 	doc_dbg("doc_ecc_bch_fix_data: flipped %d bits\n", numerrs);
660 	return numerrs;
661 }
662 
663 
664 /**
665  * doc_read_page_prepare - Prepares reading data from a flash page
666  * @docg3: the device
667  * @block0: the first plane block index on flash memory
668  * @block1: the second plane block index on flash memory
669  * @page: the page index in the block
670  * @offset: the offset in the page (must be a multiple of 4)
671  *
672  * Prepares the page to be read in the flash memory :
673  *   - tell ASIC to map the flash pages
674  *   - tell ASIC to be in read mode
675  *
676  * After a call to this method, a call to doc_read_page_finish is mandatory,
677  * to end the read cycle of the flash.
678  *
679  * Read data from a flash page. The length to be read must be between 0 and
680  * (page_size + oob_size + wear_size), ie. 532, and a multiple of 4 (because
681  * the extra bytes reading is not implemented).
682  *
683  * As pages are grouped by 2 (in 2 planes), reading from a page must be done
684  * in two steps:
685  *  - one read of 512 bytes at offset 0
686  *  - one read of 512 bytes at offset 512 + 16
687  *
688  * Returns 0 if successful, -EIO if a read error occured.
689  */
690 static int doc_read_page_prepare(struct docg3 *docg3, int block0, int block1,
691 				 int page, int offset)
692 {
693 	int wear_area = 0, ret = 0;
694 
695 	doc_dbg("doc_read_page_prepare(blocks=(%d,%d), page=%d, ofsInPage=%d)\n",
696 		block0, block1, page, offset);
697 	if (offset >= DOC_LAYOUT_WEAR_OFFSET)
698 		wear_area = 1;
699 	if (!wear_area && offset > (DOC_LAYOUT_PAGE_OOB_SIZE * 2))
700 		return -EINVAL;
701 
702 	doc_set_device_id(docg3, docg3->device_id);
703 	ret = doc_reset_seq(docg3);
704 	if (ret)
705 		goto err;
706 
707 	/* Program the flash address block and page */
708 	ret = doc_read_seek(docg3, block0, block1, page, wear_area, offset);
709 	if (ret)
710 		goto err;
711 
712 	doc_flash_command(docg3, DOC_CMD_READ_ALL_PLANES);
713 	doc_delay(docg3, 2);
714 	doc_wait_ready(docg3);
715 
716 	doc_flash_command(docg3, DOC_CMD_SET_ADDR_READ);
717 	doc_delay(docg3, 1);
718 	if (offset >= DOC_LAYOUT_PAGE_SIZE * 2)
719 		offset -= 2 * DOC_LAYOUT_PAGE_SIZE;
720 	doc_flash_address(docg3, offset >> 2);
721 	doc_delay(docg3, 1);
722 	doc_wait_ready(docg3);
723 
724 	doc_flash_command(docg3, DOC_CMD_READ_FLASH);
725 
726 	return 0;
727 err:
728 	doc_writeb(docg3, 0, DOC_DATAEND);
729 	doc_delay(docg3, 2);
730 	return -EIO;
731 }
732 
733 /**
734  * doc_read_page_getbytes - Reads bytes from a prepared page
735  * @docg3: the device
736  * @len: the number of bytes to be read (must be a multiple of 4)
737  * @buf: the buffer to be filled in
738  * @first: 1 if first time read, DOC_READADDRESS should be set
739  *
740  */
741 static int doc_read_page_getbytes(struct docg3 *docg3, int len, u_char *buf,
742 				  int first)
743 {
744 	doc_read_data_area(docg3, buf, len, first);
745 	doc_delay(docg3, 2);
746 	return len;
747 }
748 
749 /**
750  * doc_write_page_putbytes - Writes bytes into a prepared page
751  * @docg3: the device
752  * @len: the number of bytes to be written
753  * @buf: the buffer of input bytes
754  *
755  */
756 static void doc_write_page_putbytes(struct docg3 *docg3, int len,
757 				    const u_char *buf)
758 {
759 	doc_write_data_area(docg3, buf, len);
760 	doc_delay(docg3, 2);
761 }
762 
763 /**
764  * doc_get_bch_hw_ecc - Get hardware calculated BCH ECC
765  * @docg3: the device
766  * @hwecc:  the array of 7 integers where the hardware ecc will be stored
767  */
768 static void doc_get_bch_hw_ecc(struct docg3 *docg3, u8 *hwecc)
769 {
770 	int i;
771 
772 	for (i = 0; i < DOC_ECC_BCH_SIZE; i++)
773 		hwecc[i] = doc_register_readb(docg3, DOC_BCH_HW_ECC(i));
774 }
775 
776 /**
777  * doc_page_finish - Ends reading/writing of a flash page
778  * @docg3: the device
779  */
780 static void doc_page_finish(struct docg3 *docg3)
781 {
782 	doc_writeb(docg3, 0, DOC_DATAEND);
783 	doc_delay(docg3, 2);
784 }
785 
786 /**
787  * doc_read_page_finish - Ends reading of a flash page
788  * @docg3: the device
789  *
790  * As a side effect, resets the chip selector to 0. This ensures that after each
791  * read operation, the floor 0 is selected. Therefore, if the systems halts, the
792  * reboot will boot on floor 0, where the IPL is.
793  */
794 static void doc_read_page_finish(struct docg3 *docg3)
795 {
796 	doc_page_finish(docg3);
797 	doc_set_device_id(docg3, 0);
798 }
799 
800 /**
801  * calc_block_sector - Calculate blocks, pages and ofs.
802 
803  * @from: offset in flash
804  * @block0: first plane block index calculated
805  * @block1: second plane block index calculated
806  * @page: page calculated
807  * @ofs: offset in page
808  * @reliable: 0 if docg3 in normal mode, 1 if docg3 in fast mode, 2 if docg3 in
809  * reliable mode.
810  *
811  * The calculation is based on the reliable/normal mode. In normal mode, the 64
812  * pages of a block are available. In reliable mode, as pages 2*n and 2*n+1 are
813  * clones, only 32 pages per block are available.
814  */
815 static void calc_block_sector(loff_t from, int *block0, int *block1, int *page,
816 			      int *ofs, int reliable)
817 {
818 	uint sector, pages_biblock;
819 
820 	pages_biblock = DOC_LAYOUT_PAGES_PER_BLOCK * DOC_LAYOUT_NBPLANES;
821 	if (reliable == 1 || reliable == 2)
822 		pages_biblock /= 2;
823 
824 	sector = from / DOC_LAYOUT_PAGE_SIZE;
825 	*block0 = sector / pages_biblock * DOC_LAYOUT_NBPLANES;
826 	*block1 = *block0 + 1;
827 	*page = sector % pages_biblock;
828 	*page /= DOC_LAYOUT_NBPLANES;
829 	if (reliable == 1 || reliable == 2)
830 		*page *= 2;
831 	if (sector % 2)
832 		*ofs = DOC_LAYOUT_PAGE_OOB_SIZE;
833 	else
834 		*ofs = 0;
835 }
836 
837 /**
838  * doc_read_oob - Read out of band bytes from flash
839  * @mtd: the device
840  * @from: the offset from first block and first page, in bytes, aligned on page
841  *        size
842  * @ops: the mtd oob structure
843  *
844  * Reads flash memory OOB area of pages.
845  *
846  * Returns 0 if read successfull, of -EIO, -EINVAL if an error occured
847  */
848 static int doc_read_oob(struct mtd_info *mtd, loff_t from,
849 			struct mtd_oob_ops *ops)
850 {
851 	struct docg3 *docg3 = mtd->priv;
852 	int block0, block1, page, ret, ofs = 0;
853 	u8 *oobbuf = ops->oobbuf;
854 	u8 *buf = ops->datbuf;
855 	size_t len, ooblen, nbdata, nboob;
856 	u8 hwecc[DOC_ECC_BCH_SIZE], eccconf1;
857 
858 	if (buf)
859 		len = ops->len;
860 	else
861 		len = 0;
862 	if (oobbuf)
863 		ooblen = ops->ooblen;
864 	else
865 		ooblen = 0;
866 
867 	if (oobbuf && ops->mode == MTD_OPS_PLACE_OOB)
868 		oobbuf += ops->ooboffs;
869 
870 	doc_dbg("doc_read_oob(from=%lld, mode=%d, data=(%p:%zu), oob=(%p:%zu))\n",
871 		from, ops->mode, buf, len, oobbuf, ooblen);
872 	if ((len % DOC_LAYOUT_PAGE_SIZE) || (ooblen % DOC_LAYOUT_OOB_SIZE) ||
873 	    (from % DOC_LAYOUT_PAGE_SIZE))
874 		return -EINVAL;
875 
876 	ret = -EINVAL;
877 	calc_block_sector(from + len, &block0, &block1, &page, &ofs,
878 			  docg3->reliable);
879 	if (block1 > docg3->max_block)
880 		goto err;
881 
882 	ops->oobretlen = 0;
883 	ops->retlen = 0;
884 	ret = 0;
885 	while (!ret && (len > 0 || ooblen > 0)) {
886 		calc_block_sector(from, &block0, &block1, &page, &ofs,
887 			docg3->reliable);
888 		nbdata = min_t(size_t, len, (size_t)DOC_LAYOUT_PAGE_SIZE);
889 		nboob = min_t(size_t, ooblen, (size_t)DOC_LAYOUT_OOB_SIZE);
890 		ret = doc_read_page_prepare(docg3, block0, block1, page, ofs);
891 		if (ret < 0)
892 			goto err;
893 		ret = doc_read_page_ecc_init(docg3, DOC_ECC_BCH_TOTAL_BYTES);
894 		if (ret < 0)
895 			goto err_in_read;
896 		ret = doc_read_page_getbytes(docg3, nbdata, buf, 1);
897 		if (ret < nbdata)
898 			goto err_in_read;
899 		doc_read_page_getbytes(docg3, DOC_LAYOUT_PAGE_SIZE - nbdata,
900 				       NULL, 0);
901 		ret = doc_read_page_getbytes(docg3, nboob, oobbuf, 0);
902 		if (ret < nboob)
903 			goto err_in_read;
904 		doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE - nboob,
905 				       NULL, 0);
906 
907 		doc_get_bch_hw_ecc(docg3, hwecc);
908 		eccconf1 = doc_register_readb(docg3, DOC_ECCCONF1);
909 
910 		if (nboob >= DOC_LAYOUT_OOB_SIZE) {
911 			doc_dbg("OOB - INFO: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
912 				oobbuf[0], oobbuf[1], oobbuf[2], oobbuf[3],
913 				oobbuf[4], oobbuf[5], oobbuf[6]);
914 			doc_dbg("OOB - HAMMING: %02x\n", oobbuf[7]);
915 			doc_dbg("OOB - BCH_ECC: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
916 				oobbuf[8], oobbuf[9], oobbuf[10], oobbuf[11],
917 				oobbuf[12], oobbuf[13], oobbuf[14]);
918 			doc_dbg("OOB - UNUSED: %02x\n", oobbuf[15]);
919 		}
920 		doc_dbg("ECC checks: ECCConf1=%x\n", eccconf1);
921 		doc_dbg("ECC HW_ECC: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
922 			hwecc[0], hwecc[1], hwecc[2], hwecc[3], hwecc[4],
923 			hwecc[5], hwecc[6]);
924 
925 		ret = -EIO;
926 		if (is_prot_seq_error(docg3))
927 			goto err_in_read;
928 		ret = 0;
929 		if ((block0 >= DOC_LAYOUT_BLOCK_FIRST_DATA) &&
930 		    (eccconf1 & DOC_ECCCONF1_BCH_SYNDROM_ERR) &&
931 		    (eccconf1 & DOC_ECCCONF1_PAGE_IS_WRITTEN) &&
932 		    (ops->mode != MTD_OPS_RAW) &&
933 		    (nbdata == DOC_LAYOUT_PAGE_SIZE)) {
934 			ret = doc_ecc_bch_fix_data(docg3, buf, hwecc);
935 			if (ret < 0) {
936 				mtd->ecc_stats.failed++;
937 				ret = -EBADMSG;
938 			}
939 			if (ret > 0) {
940 				mtd->ecc_stats.corrected += ret;
941 				ret = -EUCLEAN;
942 			}
943 		}
944 
945 		doc_read_page_finish(docg3);
946 		ops->retlen += nbdata;
947 		ops->oobretlen += nboob;
948 		buf += nbdata;
949 		oobbuf += nboob;
950 		len -= nbdata;
951 		ooblen -= nboob;
952 		from += DOC_LAYOUT_PAGE_SIZE;
953 	}
954 
955 	return ret;
956 err_in_read:
957 	doc_read_page_finish(docg3);
958 err:
959 	return ret;
960 }
961 
962 /**
963  * doc_read - Read bytes from flash
964  * @mtd: the device
965  * @from: the offset from first block and first page, in bytes, aligned on page
966  *        size
967  * @len: the number of bytes to read (must be a multiple of 4)
968  * @retlen: the number of bytes actually read
969  * @buf: the filled in buffer
970  *
971  * Reads flash memory pages. This function does not read the OOB chunk, but only
972  * the page data.
973  *
974  * Returns 0 if read successfull, of -EIO, -EINVAL if an error occured
975  */
976 static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
977 	     size_t *retlen, u_char *buf)
978 {
979 	struct mtd_oob_ops ops;
980 	size_t ret;
981 
982 	memset(&ops, 0, sizeof(ops));
983 	ops.datbuf = buf;
984 	ops.len = len;
985 	ops.mode = MTD_OPS_AUTO_OOB;
986 
987 	ret = doc_read_oob(mtd, from, &ops);
988 	*retlen = ops.retlen;
989 	return ret;
990 }
991 
992 static int doc_reload_bbt(struct docg3 *docg3)
993 {
994 	int block = DOC_LAYOUT_BLOCK_BBT;
995 	int ret = 0, nbpages, page;
996 	u_char *buf = docg3->bbt;
997 
998 	nbpages = DIV_ROUND_UP(docg3->max_block + 1, 8 * DOC_LAYOUT_PAGE_SIZE);
999 	for (page = 0; !ret && (page < nbpages); page++) {
1000 		ret = doc_read_page_prepare(docg3, block, block + 1,
1001 					    page + DOC_LAYOUT_PAGE_BBT, 0);
1002 		if (!ret)
1003 			ret = doc_read_page_ecc_init(docg3,
1004 						     DOC_LAYOUT_PAGE_SIZE);
1005 		if (!ret)
1006 			doc_read_page_getbytes(docg3, DOC_LAYOUT_PAGE_SIZE,
1007 					       buf, 1);
1008 		buf += DOC_LAYOUT_PAGE_SIZE;
1009 	}
1010 	doc_read_page_finish(docg3);
1011 	return ret;
1012 }
1013 
1014 /**
1015  * doc_block_isbad - Checks whether a block is good or not
1016  * @mtd: the device
1017  * @from: the offset to find the correct block
1018  *
1019  * Returns 1 if block is bad, 0 if block is good
1020  */
1021 static int doc_block_isbad(struct mtd_info *mtd, loff_t from)
1022 {
1023 	struct docg3 *docg3 = mtd->priv;
1024 	int block0, block1, page, ofs, is_good;
1025 
1026 	calc_block_sector(from, &block0, &block1, &page, &ofs,
1027 		docg3->reliable);
1028 	doc_dbg("doc_block_isbad(from=%lld) => block=(%d,%d), page=%d, ofs=%d\n",
1029 		from, block0, block1, page, ofs);
1030 
1031 	if (block0 < DOC_LAYOUT_BLOCK_FIRST_DATA)
1032 		return 0;
1033 	if (block1 > docg3->max_block)
1034 		return -EINVAL;
1035 
1036 	is_good = docg3->bbt[block0 >> 3] & (1 << (block0 & 0x7));
1037 	return !is_good;
1038 }
1039 
1040 #if 0
1041 /**
1042  * doc_get_erase_count - Get block erase count
1043  * @docg3: the device
1044  * @from: the offset in which the block is.
1045  *
1046  * Get the number of times a block was erased. The number is the maximum of
1047  * erase times between first and second plane (which should be equal normally).
1048  *
1049  * Returns The number of erases, or -EINVAL or -EIO on error.
1050  */
1051 static int doc_get_erase_count(struct docg3 *docg3, loff_t from)
1052 {
1053 	u8 buf[DOC_LAYOUT_WEAR_SIZE];
1054 	int ret, plane1_erase_count, plane2_erase_count;
1055 	int block0, block1, page, ofs;
1056 
1057 	doc_dbg("doc_get_erase_count(from=%lld, buf=%p)\n", from, buf);
1058 	if (from % DOC_LAYOUT_PAGE_SIZE)
1059 		return -EINVAL;
1060 	calc_block_sector(from, &block0, &block1, &page, &ofs, docg3->reliable);
1061 	if (block1 > docg3->max_block)
1062 		return -EINVAL;
1063 
1064 	ret = doc_reset_seq(docg3);
1065 	if (!ret)
1066 		ret = doc_read_page_prepare(docg3, block0, block1, page,
1067 					    ofs + DOC_LAYOUT_WEAR_OFFSET);
1068 	if (!ret)
1069 		ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_WEAR_SIZE,
1070 					     buf, 1);
1071 	doc_read_page_finish(docg3);
1072 
1073 	if (ret || (buf[0] != DOC_ERASE_MARK) || (buf[2] != DOC_ERASE_MARK))
1074 		return -EIO;
1075 	plane1_erase_count = (u8)(~buf[1]) | ((u8)(~buf[4]) << 8)
1076 		| ((u8)(~buf[5]) << 16);
1077 	plane2_erase_count = (u8)(~buf[3]) | ((u8)(~buf[6]) << 8)
1078 		| ((u8)(~buf[7]) << 16);
1079 
1080 	return max(plane1_erase_count, plane2_erase_count);
1081 }
1082 #endif
1083 
1084 /**
1085  * doc_get_op_status - get erase/write operation status
1086  * @docg3: the device
1087  *
1088  * Queries the status from the chip, and returns it
1089  *
1090  * Returns the status (bits DOC_PLANES_STATUS_*)
1091  */
1092 static int doc_get_op_status(struct docg3 *docg3)
1093 {
1094 	u8 status;
1095 
1096 	doc_flash_sequence(docg3, DOC_SEQ_PLANES_STATUS);
1097 	doc_flash_command(docg3, DOC_CMD_PLANES_STATUS);
1098 	doc_delay(docg3, 5);
1099 
1100 	doc_ecc_disable(docg3);
1101 	doc_read_data_area(docg3, &status, 1, 1);
1102 	return status;
1103 }
1104 
1105 /**
1106  * doc_write_erase_wait_status - wait for write or erase completion
1107  * @docg3: the device
1108  *
1109  * Wait for the chip to be ready again after erase or write operation, and check
1110  * erase/write status.
1111  *
1112  * Returns 0 if erase successfull, -EIO if erase/write issue, -ETIMEOUT if
1113  * timeout
1114  */
1115 static int doc_write_erase_wait_status(struct docg3 *docg3)
1116 {
1117 	int status, ret = 0;
1118 
1119 	if (!doc_is_ready(docg3))
1120 		usleep_range(3000, 3000);
1121 	if (!doc_is_ready(docg3)) {
1122 		doc_dbg("Timeout reached and the chip is still not ready\n");
1123 		ret = -EAGAIN;
1124 		goto out;
1125 	}
1126 
1127 	status = doc_get_op_status(docg3);
1128 	if (status & DOC_PLANES_STATUS_FAIL) {
1129 		doc_dbg("Erase/Write failed on (a) plane(s), status = %x\n",
1130 			status);
1131 		ret = -EIO;
1132 	}
1133 
1134 out:
1135 	doc_page_finish(docg3);
1136 	return ret;
1137 }
1138 
1139 /**
1140  * doc_erase_block - Erase a couple of blocks
1141  * @docg3: the device
1142  * @block0: the first block to erase (leftmost plane)
1143  * @block1: the second block to erase (rightmost plane)
1144  *
1145  * Erase both blocks, and return operation status
1146  *
1147  * Returns 0 if erase successful, -EIO if erase issue, -ETIMEOUT if chip not
1148  * ready for too long
1149  */
1150 static int doc_erase_block(struct docg3 *docg3, int block0, int block1)
1151 {
1152 	int ret, sector;
1153 
1154 	doc_dbg("doc_erase_block(blocks=(%d,%d))\n", block0, block1);
1155 	ret = doc_reset_seq(docg3);
1156 	if (ret)
1157 		return -EIO;
1158 
1159 	doc_set_reliable_mode(docg3);
1160 	doc_flash_sequence(docg3, DOC_SEQ_ERASE);
1161 
1162 	sector = block0 << DOC_ADDR_BLOCK_SHIFT;
1163 	doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
1164 	doc_setup_addr_sector(docg3, sector);
1165 	sector = block1 << DOC_ADDR_BLOCK_SHIFT;
1166 	doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
1167 	doc_setup_addr_sector(docg3, sector);
1168 	doc_delay(docg3, 1);
1169 
1170 	doc_flash_command(docg3, DOC_CMD_ERASECYCLE2);
1171 	doc_delay(docg3, 2);
1172 
1173 	if (is_prot_seq_error(docg3)) {
1174 		doc_err("Erase blocks %d,%d error\n", block0, block1);
1175 		return -EIO;
1176 	}
1177 
1178 	return doc_write_erase_wait_status(docg3);
1179 }
1180 
1181 /**
1182  * doc_erase - Erase a portion of the chip
1183  * @mtd: the device
1184  * @info: the erase info
1185  *
1186  * Erase a bunch of contiguous blocks, by pairs, as a "mtd" page of 1024 is
1187  * split into 2 pages of 512 bytes on 2 contiguous blocks.
1188  *
1189  * Returns 0 if erase successful, -EINVAL if adressing error, -EIO if erase
1190  * issue
1191  */
1192 static int doc_erase(struct mtd_info *mtd, struct erase_info *info)
1193 {
1194 	struct docg3 *docg3 = mtd->priv;
1195 	uint64_t len;
1196 	int block0, block1, page, ret, ofs = 0;
1197 
1198 	doc_dbg("doc_erase(from=%lld, len=%lld\n", info->addr, info->len);
1199 	doc_set_device_id(docg3, docg3->device_id);
1200 
1201 	info->state = MTD_ERASE_PENDING;
1202 	calc_block_sector(info->addr + info->len, &block0, &block1, &page,
1203 			  &ofs, docg3->reliable);
1204 	ret = -EINVAL;
1205 	if (block1 > docg3->max_block || page || ofs)
1206 		goto reset_err;
1207 
1208 	ret = 0;
1209 	calc_block_sector(info->addr, &block0, &block1, &page, &ofs,
1210 			  docg3->reliable);
1211 	doc_set_reliable_mode(docg3);
1212 	for (len = info->len; !ret && len > 0; len -= mtd->erasesize) {
1213 		info->state = MTD_ERASING;
1214 		ret = doc_erase_block(docg3, block0, block1);
1215 		block0 += 2;
1216 		block1 += 2;
1217 	}
1218 
1219 	if (ret)
1220 		goto reset_err;
1221 
1222 	info->state = MTD_ERASE_DONE;
1223 	return 0;
1224 
1225 reset_err:
1226 	info->state = MTD_ERASE_FAILED;
1227 	return ret;
1228 }
1229 
1230 /**
1231  * doc_write_page - Write a single page to the chip
1232  * @docg3: the device
1233  * @to: the offset from first block and first page, in bytes, aligned on page
1234  *      size
1235  * @buf: buffer to get bytes from
1236  * @oob: buffer to get out of band bytes from (can be NULL if no OOB should be
1237  *       written)
1238  * @autoecc: if 0, all 16 bytes from OOB are taken, regardless of HW Hamming or
1239  *           BCH computations. If 1, only bytes 0-7 and byte 15 are taken,
1240  *           remaining ones are filled with hardware Hamming and BCH
1241  *           computations. Its value is not meaningfull is oob == NULL.
1242  *
1243  * Write one full page (ie. 1 page split on two planes), of 512 bytes, with the
1244  * OOB data. The OOB ECC is automatically computed by the hardware Hamming and
1245  * BCH generator if autoecc is not null.
1246  *
1247  * Returns 0 if write successful, -EIO if write error, -EAGAIN if timeout
1248  */
1249 static int doc_write_page(struct docg3 *docg3, loff_t to, const u_char *buf,
1250 			  const u_char *oob, int autoecc)
1251 {
1252 	int block0, block1, page, ret, ofs = 0;
1253 	u8 hwecc[DOC_ECC_BCH_SIZE], hamming;
1254 
1255 	doc_dbg("doc_write_page(to=%lld)\n", to);
1256 	calc_block_sector(to, &block0, &block1, &page, &ofs, docg3->reliable);
1257 
1258 	doc_set_device_id(docg3, docg3->device_id);
1259 	ret = doc_reset_seq(docg3);
1260 	if (ret)
1261 		goto err;
1262 
1263 	/* Program the flash address block and page */
1264 	ret = doc_write_seek(docg3, block0, block1, page, ofs);
1265 	if (ret)
1266 		goto err;
1267 
1268 	doc_write_page_ecc_init(docg3, DOC_ECC_BCH_TOTAL_BYTES);
1269 	doc_delay(docg3, 2);
1270 	doc_write_page_putbytes(docg3, DOC_LAYOUT_PAGE_SIZE, buf);
1271 
1272 	if (oob && autoecc) {
1273 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_PAGEINFO_SZ, oob);
1274 		doc_delay(docg3, 2);
1275 		oob += DOC_LAYOUT_OOB_UNUSED_OFS;
1276 
1277 		hamming = doc_register_readb(docg3, DOC_HAMMINGPARITY);
1278 		doc_delay(docg3, 2);
1279 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_HAMMING_SZ,
1280 					&hamming);
1281 		doc_delay(docg3, 2);
1282 
1283 		doc_get_bch_hw_ecc(docg3, hwecc);
1284 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_BCH_SZ, hwecc);
1285 		doc_delay(docg3, 2);
1286 
1287 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_UNUSED_SZ, oob);
1288 	}
1289 	if (oob && !autoecc)
1290 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_SIZE, oob);
1291 
1292 	doc_delay(docg3, 2);
1293 	doc_page_finish(docg3);
1294 	doc_delay(docg3, 2);
1295 	doc_flash_command(docg3, DOC_CMD_PROG_CYCLE2);
1296 	doc_delay(docg3, 2);
1297 
1298 	/*
1299 	 * The wait status will perform another doc_page_finish() call, but that
1300 	 * seems to please the docg3, so leave it.
1301 	 */
1302 	ret = doc_write_erase_wait_status(docg3);
1303 	return ret;
1304 err:
1305 	doc_read_page_finish(docg3);
1306 	return ret;
1307 }
1308 
1309 /**
1310  * doc_guess_autoecc - Guess autoecc mode from mbd_oob_ops
1311  * @ops: the oob operations
1312  *
1313  * Returns 0 or 1 if success, -EINVAL if invalid oob mode
1314  */
1315 static int doc_guess_autoecc(struct mtd_oob_ops *ops)
1316 {
1317 	int autoecc;
1318 
1319 	switch (ops->mode) {
1320 	case MTD_OPS_PLACE_OOB:
1321 	case MTD_OPS_AUTO_OOB:
1322 		autoecc = 1;
1323 		break;
1324 	case MTD_OPS_RAW:
1325 		autoecc = 0;
1326 		break;
1327 	default:
1328 		autoecc = -EINVAL;
1329 	}
1330 	return autoecc;
1331 }
1332 
1333 /**
1334  * doc_fill_autooob - Fill a 16 bytes OOB from 8 non-ECC bytes
1335  * @dst: the target 16 bytes OOB buffer
1336  * @oobsrc: the source 8 bytes non-ECC OOB buffer
1337  *
1338  */
1339 static void doc_fill_autooob(u8 *dst, u8 *oobsrc)
1340 {
1341 	memcpy(dst, oobsrc, DOC_LAYOUT_OOB_PAGEINFO_SZ);
1342 	dst[DOC_LAYOUT_OOB_UNUSED_OFS] = oobsrc[DOC_LAYOUT_OOB_PAGEINFO_SZ];
1343 }
1344 
1345 /**
1346  * doc_backup_oob - Backup OOB into docg3 structure
1347  * @docg3: the device
1348  * @to: the page offset in the chip
1349  * @ops: the OOB size and buffer
1350  *
1351  * As the docg3 should write a page with its OOB in one pass, and some userland
1352  * applications do write_oob() to setup the OOB and then write(), store the OOB
1353  * into a temporary storage. This is very dangerous, as 2 concurrent
1354  * applications could store an OOB, and then write their pages (which will
1355  * result into one having its OOB corrupted).
1356  *
1357  * The only reliable way would be for userland to call doc_write_oob() with both
1358  * the page data _and_ the OOB area.
1359  *
1360  * Returns 0 if success, -EINVAL if ops content invalid
1361  */
1362 static int doc_backup_oob(struct docg3 *docg3, loff_t to,
1363 			  struct mtd_oob_ops *ops)
1364 {
1365 	int ooblen = ops->ooblen, autoecc;
1366 
1367 	if (ooblen != DOC_LAYOUT_OOB_SIZE)
1368 		return -EINVAL;
1369 	autoecc = doc_guess_autoecc(ops);
1370 	if (autoecc < 0)
1371 		return autoecc;
1372 
1373 	docg3->oob_write_ofs = to;
1374 	docg3->oob_autoecc = autoecc;
1375 	if (ops->mode == MTD_OPS_AUTO_OOB) {
1376 		doc_fill_autooob(docg3->oob_write_buf, ops->oobbuf);
1377 		ops->oobretlen = 8;
1378 	} else {
1379 		memcpy(docg3->oob_write_buf, ops->oobbuf, DOC_LAYOUT_OOB_SIZE);
1380 		ops->oobretlen = DOC_LAYOUT_OOB_SIZE;
1381 	}
1382 	return 0;
1383 }
1384 
1385 /**
1386  * doc_write_oob - Write out of band bytes to flash
1387  * @mtd: the device
1388  * @ofs: the offset from first block and first page, in bytes, aligned on page
1389  *       size
1390  * @ops: the mtd oob structure
1391  *
1392  * Either write OOB data into a temporary buffer, for the subsequent write
1393  * page. The provided OOB should be 16 bytes long. If a data buffer is provided
1394  * as well, issue the page write.
1395  * Or provide data without OOB, and then a all zeroed OOB will be used (ECC will
1396  * still be filled in if asked for).
1397  *
1398  * Returns 0 is successfull, EINVAL if length is not 14 bytes
1399  */
1400 static int doc_write_oob(struct mtd_info *mtd, loff_t ofs,
1401 			 struct mtd_oob_ops *ops)
1402 {
1403 	struct docg3 *docg3 = mtd->priv;
1404 	int block0, block1, page, ret, pofs = 0, autoecc, oobdelta;
1405 	u8 *oobbuf = ops->oobbuf;
1406 	u8 *buf = ops->datbuf;
1407 	size_t len, ooblen;
1408 	u8 oob[DOC_LAYOUT_OOB_SIZE];
1409 
1410 	if (buf)
1411 		len = ops->len;
1412 	else
1413 		len = 0;
1414 	if (oobbuf)
1415 		ooblen = ops->ooblen;
1416 	else
1417 		ooblen = 0;
1418 
1419 	if (oobbuf && ops->mode == MTD_OPS_PLACE_OOB)
1420 		oobbuf += ops->ooboffs;
1421 
1422 	doc_dbg("doc_write_oob(from=%lld, mode=%d, data=(%p:%zu), oob=(%p:%zu))\n",
1423 		ofs, ops->mode, buf, len, oobbuf, ooblen);
1424 	switch (ops->mode) {
1425 	case MTD_OPS_PLACE_OOB:
1426 	case MTD_OPS_RAW:
1427 		oobdelta = mtd->oobsize;
1428 		break;
1429 	case MTD_OPS_AUTO_OOB:
1430 		oobdelta = mtd->ecclayout->oobavail;
1431 		break;
1432 	default:
1433 		oobdelta = 0;
1434 	}
1435 	if ((len % DOC_LAYOUT_PAGE_SIZE) || (ooblen % oobdelta) ||
1436 	    (ofs % DOC_LAYOUT_PAGE_SIZE))
1437 		return -EINVAL;
1438 	if (len && ooblen &&
1439 	    (len / DOC_LAYOUT_PAGE_SIZE) != (ooblen / oobdelta))
1440 		return -EINVAL;
1441 
1442 	ret = -EINVAL;
1443 	calc_block_sector(ofs + len, &block0, &block1, &page, &pofs,
1444 			  docg3->reliable);
1445 	if (block1 > docg3->max_block)
1446 		goto err;
1447 
1448 	ops->oobretlen = 0;
1449 	ops->retlen = 0;
1450 	ret = 0;
1451 	if (len == 0 && ooblen == 0)
1452 		return -EINVAL;
1453 	if (len == 0 && ooblen > 0)
1454 		return doc_backup_oob(docg3, ofs, ops);
1455 
1456 	autoecc = doc_guess_autoecc(ops);
1457 	if (autoecc < 0)
1458 		return autoecc;
1459 
1460 	while (!ret && len > 0) {
1461 		memset(oob, 0, sizeof(oob));
1462 		if (ofs == docg3->oob_write_ofs)
1463 			memcpy(oob, docg3->oob_write_buf, DOC_LAYOUT_OOB_SIZE);
1464 		else if (ooblen > 0 && ops->mode == MTD_OPS_AUTO_OOB)
1465 			doc_fill_autooob(oob, oobbuf);
1466 		else if (ooblen > 0)
1467 			memcpy(oob, oobbuf, DOC_LAYOUT_OOB_SIZE);
1468 		ret = doc_write_page(docg3, ofs, buf, oob, autoecc);
1469 
1470 		ofs += DOC_LAYOUT_PAGE_SIZE;
1471 		len -= DOC_LAYOUT_PAGE_SIZE;
1472 		buf += DOC_LAYOUT_PAGE_SIZE;
1473 		if (ooblen) {
1474 			oobbuf += oobdelta;
1475 			ooblen -= oobdelta;
1476 			ops->oobretlen += oobdelta;
1477 		}
1478 		ops->retlen += DOC_LAYOUT_PAGE_SIZE;
1479 	}
1480 err:
1481 	doc_set_device_id(docg3, 0);
1482 	return ret;
1483 }
1484 
1485 /**
1486  * doc_write - Write a buffer to the chip
1487  * @mtd: the device
1488  * @to: the offset from first block and first page, in bytes, aligned on page
1489  *      size
1490  * @len: the number of bytes to write (must be a full page size, ie. 512)
1491  * @retlen: the number of bytes actually written (0 or 512)
1492  * @buf: the buffer to get bytes from
1493  *
1494  * Writes data to the chip.
1495  *
1496  * Returns 0 if write successful, -EIO if write error
1497  */
1498 static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
1499 		     size_t *retlen, const u_char *buf)
1500 {
1501 	struct docg3 *docg3 = mtd->priv;
1502 	int ret;
1503 	struct mtd_oob_ops ops;
1504 
1505 	doc_dbg("doc_write(to=%lld, len=%zu)\n", to, len);
1506 	ops.datbuf = (char *)buf;
1507 	ops.len = len;
1508 	ops.mode = MTD_OPS_PLACE_OOB;
1509 	ops.oobbuf = NULL;
1510 	ops.ooblen = 0;
1511 	ops.ooboffs = 0;
1512 
1513 	ret = doc_write_oob(mtd, to, &ops);
1514 	*retlen = ops.retlen;
1515 	return ret;
1516 }
1517 
1518 static struct docg3 *sysfs_dev2docg3(struct device *dev,
1519 				     struct device_attribute *attr)
1520 {
1521 	int floor;
1522 	struct platform_device *pdev = to_platform_device(dev);
1523 	struct mtd_info **docg3_floors = platform_get_drvdata(pdev);
1524 
1525 	floor = attr->attr.name[1] - '0';
1526 	if (floor < 0 || floor >= DOC_MAX_NBFLOORS)
1527 		return NULL;
1528 	else
1529 		return docg3_floors[floor]->priv;
1530 }
1531 
1532 static ssize_t dps0_is_key_locked(struct device *dev,
1533 				  struct device_attribute *attr, char *buf)
1534 {
1535 	struct docg3 *docg3 = sysfs_dev2docg3(dev, attr);
1536 	int dps0;
1537 
1538 	doc_set_device_id(docg3, docg3->device_id);
1539 	dps0 = doc_register_readb(docg3, DOC_DPS0_STATUS);
1540 	doc_set_device_id(docg3, 0);
1541 
1542 	return sprintf(buf, "%d\n", !(dps0 & DOC_DPS_KEY_OK));
1543 }
1544 
1545 static ssize_t dps1_is_key_locked(struct device *dev,
1546 				  struct device_attribute *attr, char *buf)
1547 {
1548 	struct docg3 *docg3 = sysfs_dev2docg3(dev, attr);
1549 	int dps1;
1550 
1551 	doc_set_device_id(docg3, docg3->device_id);
1552 	dps1 = doc_register_readb(docg3, DOC_DPS1_STATUS);
1553 	doc_set_device_id(docg3, 0);
1554 
1555 	return sprintf(buf, "%d\n", !(dps1 & DOC_DPS_KEY_OK));
1556 }
1557 
1558 static ssize_t dps0_insert_key(struct device *dev,
1559 			       struct device_attribute *attr,
1560 			       const char *buf, size_t count)
1561 {
1562 	struct docg3 *docg3 = sysfs_dev2docg3(dev, attr);
1563 	int i;
1564 
1565 	if (count != DOC_LAYOUT_DPS_KEY_LENGTH)
1566 		return -EINVAL;
1567 
1568 	doc_set_device_id(docg3, docg3->device_id);
1569 	for (i = 0; i < DOC_LAYOUT_DPS_KEY_LENGTH; i++)
1570 		doc_writeb(docg3, buf[i], DOC_DPS0_KEY);
1571 	doc_set_device_id(docg3, 0);
1572 	return count;
1573 }
1574 
1575 static ssize_t dps1_insert_key(struct device *dev,
1576 			       struct device_attribute *attr,
1577 			       const char *buf, size_t count)
1578 {
1579 	struct docg3 *docg3 = sysfs_dev2docg3(dev, attr);
1580 	int i;
1581 
1582 	if (count != DOC_LAYOUT_DPS_KEY_LENGTH)
1583 		return -EINVAL;
1584 
1585 	doc_set_device_id(docg3, docg3->device_id);
1586 	for (i = 0; i < DOC_LAYOUT_DPS_KEY_LENGTH; i++)
1587 		doc_writeb(docg3, buf[i], DOC_DPS1_KEY);
1588 	doc_set_device_id(docg3, 0);
1589 	return count;
1590 }
1591 
1592 #define FLOOR_SYSFS(id) { \
1593 	__ATTR(f##id##_dps0_is_keylocked, S_IRUGO, dps0_is_key_locked, NULL), \
1594 	__ATTR(f##id##_dps1_is_keylocked, S_IRUGO, dps1_is_key_locked, NULL), \
1595 	__ATTR(f##id##_dps0_protection_key, S_IWUGO, NULL, dps0_insert_key), \
1596 	__ATTR(f##id##_dps1_protection_key, S_IWUGO, NULL, dps1_insert_key), \
1597 }
1598 
1599 static struct device_attribute doc_sys_attrs[DOC_MAX_NBFLOORS][4] = {
1600 	FLOOR_SYSFS(0), FLOOR_SYSFS(1), FLOOR_SYSFS(2), FLOOR_SYSFS(3)
1601 };
1602 
1603 static int doc_register_sysfs(struct platform_device *pdev,
1604 			      struct mtd_info **floors)
1605 {
1606 	int ret = 0, floor, i = 0;
1607 	struct device *dev = &pdev->dev;
1608 
1609 	for (floor = 0; !ret && floor < DOC_MAX_NBFLOORS && floors[floor];
1610 	     floor++)
1611 		for (i = 0; !ret && i < 4; i++)
1612 			ret = device_create_file(dev, &doc_sys_attrs[floor][i]);
1613 	if (!ret)
1614 		return 0;
1615 	do {
1616 		while (--i >= 0)
1617 			device_remove_file(dev, &doc_sys_attrs[floor][i]);
1618 		i = 4;
1619 	} while (--floor >= 0);
1620 	return ret;
1621 }
1622 
1623 static void doc_unregister_sysfs(struct platform_device *pdev,
1624 				 struct mtd_info **floors)
1625 {
1626 	struct device *dev = &pdev->dev;
1627 	int floor, i;
1628 
1629 	for (floor = 0; floor < DOC_MAX_NBFLOORS && floors[floor];
1630 	     floor++)
1631 		for (i = 0; i < 4; i++)
1632 			device_remove_file(dev, &doc_sys_attrs[floor][i]);
1633 }
1634 
1635 /*
1636  * Debug sysfs entries
1637  */
1638 static int dbg_flashctrl_show(struct seq_file *s, void *p)
1639 {
1640 	struct docg3 *docg3 = (struct docg3 *)s->private;
1641 
1642 	int pos = 0;
1643 	u8 fctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
1644 
1645 	pos += seq_printf(s,
1646 		 "FlashControl : 0x%02x (%s,CE# %s,%s,%s,flash %s)\n",
1647 		 fctrl,
1648 		 fctrl & DOC_CTRL_VIOLATION ? "protocol violation" : "-",
1649 		 fctrl & DOC_CTRL_CE ? "active" : "inactive",
1650 		 fctrl & DOC_CTRL_PROTECTION_ERROR ? "protection error" : "-",
1651 		 fctrl & DOC_CTRL_SEQUENCE_ERROR ? "sequence error" : "-",
1652 		 fctrl & DOC_CTRL_FLASHREADY ? "ready" : "not ready");
1653 	return pos;
1654 }
1655 DEBUGFS_RO_ATTR(flashcontrol, dbg_flashctrl_show);
1656 
1657 static int dbg_asicmode_show(struct seq_file *s, void *p)
1658 {
1659 	struct docg3 *docg3 = (struct docg3 *)s->private;
1660 
1661 	int pos = 0;
1662 	int pctrl = doc_register_readb(docg3, DOC_ASICMODE);
1663 	int mode = pctrl & 0x03;
1664 
1665 	pos += seq_printf(s,
1666 			 "%04x : RAM_WE=%d,RSTIN_RESET=%d,BDETCT_RESET=%d,WRITE_ENABLE=%d,POWERDOWN=%d,MODE=%d%d (",
1667 			 pctrl,
1668 			 pctrl & DOC_ASICMODE_RAM_WE ? 1 : 0,
1669 			 pctrl & DOC_ASICMODE_RSTIN_RESET ? 1 : 0,
1670 			 pctrl & DOC_ASICMODE_BDETCT_RESET ? 1 : 0,
1671 			 pctrl & DOC_ASICMODE_MDWREN ? 1 : 0,
1672 			 pctrl & DOC_ASICMODE_POWERDOWN ? 1 : 0,
1673 			 mode >> 1, mode & 0x1);
1674 
1675 	switch (mode) {
1676 	case DOC_ASICMODE_RESET:
1677 		pos += seq_printf(s, "reset");
1678 		break;
1679 	case DOC_ASICMODE_NORMAL:
1680 		pos += seq_printf(s, "normal");
1681 		break;
1682 	case DOC_ASICMODE_POWERDOWN:
1683 		pos += seq_printf(s, "powerdown");
1684 		break;
1685 	}
1686 	pos += seq_printf(s, ")\n");
1687 	return pos;
1688 }
1689 DEBUGFS_RO_ATTR(asic_mode, dbg_asicmode_show);
1690 
1691 static int dbg_device_id_show(struct seq_file *s, void *p)
1692 {
1693 	struct docg3 *docg3 = (struct docg3 *)s->private;
1694 	int pos = 0;
1695 	int id = doc_register_readb(docg3, DOC_DEVICESELECT);
1696 
1697 	pos += seq_printf(s, "DeviceId = %d\n", id);
1698 	return pos;
1699 }
1700 DEBUGFS_RO_ATTR(device_id, dbg_device_id_show);
1701 
1702 static int dbg_protection_show(struct seq_file *s, void *p)
1703 {
1704 	struct docg3 *docg3 = (struct docg3 *)s->private;
1705 	int pos = 0;
1706 	int protect, dps0, dps0_low, dps0_high, dps1, dps1_low, dps1_high;
1707 
1708 	protect = doc_register_readb(docg3, DOC_PROTECTION);
1709 	dps0 = doc_register_readb(docg3, DOC_DPS0_STATUS);
1710 	dps0_low = doc_register_readw(docg3, DOC_DPS0_ADDRLOW);
1711 	dps0_high = doc_register_readw(docg3, DOC_DPS0_ADDRHIGH);
1712 	dps1 = doc_register_readb(docg3, DOC_DPS1_STATUS);
1713 	dps1_low = doc_register_readw(docg3, DOC_DPS1_ADDRLOW);
1714 	dps1_high = doc_register_readw(docg3, DOC_DPS1_ADDRHIGH);
1715 
1716 	pos += seq_printf(s, "Protection = 0x%02x (",
1717 			 protect);
1718 	if (protect & DOC_PROTECT_FOUNDRY_OTP_LOCK)
1719 		pos += seq_printf(s, "FOUNDRY_OTP_LOCK,");
1720 	if (protect & DOC_PROTECT_CUSTOMER_OTP_LOCK)
1721 		pos += seq_printf(s, "CUSTOMER_OTP_LOCK,");
1722 	if (protect & DOC_PROTECT_LOCK_INPUT)
1723 		pos += seq_printf(s, "LOCK_INPUT,");
1724 	if (protect & DOC_PROTECT_STICKY_LOCK)
1725 		pos += seq_printf(s, "STICKY_LOCK,");
1726 	if (protect & DOC_PROTECT_PROTECTION_ENABLED)
1727 		pos += seq_printf(s, "PROTECTION ON,");
1728 	if (protect & DOC_PROTECT_IPL_DOWNLOAD_LOCK)
1729 		pos += seq_printf(s, "IPL_DOWNLOAD_LOCK,");
1730 	if (protect & DOC_PROTECT_PROTECTION_ERROR)
1731 		pos += seq_printf(s, "PROTECT_ERR,");
1732 	else
1733 		pos += seq_printf(s, "NO_PROTECT_ERR");
1734 	pos += seq_printf(s, ")\n");
1735 
1736 	pos += seq_printf(s, "DPS0 = 0x%02x : "
1737 			 "Protected area [0x%x - 0x%x] : OTP=%d, READ=%d, "
1738 			 "WRITE=%d, HW_LOCK=%d, KEY_OK=%d\n",
1739 			 dps0, dps0_low, dps0_high,
1740 			 !!(dps0 & DOC_DPS_OTP_PROTECTED),
1741 			 !!(dps0 & DOC_DPS_READ_PROTECTED),
1742 			 !!(dps0 & DOC_DPS_WRITE_PROTECTED),
1743 			 !!(dps0 & DOC_DPS_HW_LOCK_ENABLED),
1744 			 !!(dps0 & DOC_DPS_KEY_OK));
1745 	pos += seq_printf(s, "DPS1 = 0x%02x : "
1746 			 "Protected area [0x%x - 0x%x] : OTP=%d, READ=%d, "
1747 			 "WRITE=%d, HW_LOCK=%d, KEY_OK=%d\n",
1748 			 dps1, dps1_low, dps1_high,
1749 			 !!(dps1 & DOC_DPS_OTP_PROTECTED),
1750 			 !!(dps1 & DOC_DPS_READ_PROTECTED),
1751 			 !!(dps1 & DOC_DPS_WRITE_PROTECTED),
1752 			 !!(dps1 & DOC_DPS_HW_LOCK_ENABLED),
1753 			 !!(dps1 & DOC_DPS_KEY_OK));
1754 	return pos;
1755 }
1756 DEBUGFS_RO_ATTR(protection, dbg_protection_show);
1757 
1758 static int __init doc_dbg_register(struct docg3 *docg3)
1759 {
1760 	struct dentry *root, *entry;
1761 
1762 	root = debugfs_create_dir("docg3", NULL);
1763 	if (!root)
1764 		return -ENOMEM;
1765 
1766 	entry = debugfs_create_file("flashcontrol", S_IRUSR, root, docg3,
1767 				  &flashcontrol_fops);
1768 	if (entry)
1769 		entry = debugfs_create_file("asic_mode", S_IRUSR, root,
1770 					    docg3, &asic_mode_fops);
1771 	if (entry)
1772 		entry = debugfs_create_file("device_id", S_IRUSR, root,
1773 					    docg3, &device_id_fops);
1774 	if (entry)
1775 		entry = debugfs_create_file("protection", S_IRUSR, root,
1776 					    docg3, &protection_fops);
1777 	if (entry) {
1778 		docg3->debugfs_root = root;
1779 		return 0;
1780 	} else {
1781 		debugfs_remove_recursive(root);
1782 		return -ENOMEM;
1783 	}
1784 }
1785 
1786 static void __exit doc_dbg_unregister(struct docg3 *docg3)
1787 {
1788 	debugfs_remove_recursive(docg3->debugfs_root);
1789 }
1790 
1791 /**
1792  * doc_set_driver_info - Fill the mtd_info structure and docg3 structure
1793  * @chip_id: The chip ID of the supported chip
1794  * @mtd: The structure to fill
1795  */
1796 static void __init doc_set_driver_info(int chip_id, struct mtd_info *mtd)
1797 {
1798 	struct docg3 *docg3 = mtd->priv;
1799 	int cfg;
1800 
1801 	cfg = doc_register_readb(docg3, DOC_CONFIGURATION);
1802 	docg3->if_cfg = (cfg & DOC_CONF_IF_CFG ? 1 : 0);
1803 	docg3->reliable = reliable_mode;
1804 
1805 	switch (chip_id) {
1806 	case DOC_CHIPID_G3:
1807 		mtd->name = kasprintf(GFP_KERNEL, "DiskOnChip G3 floor %d",
1808 				      docg3->device_id);
1809 		docg3->max_block = 2047;
1810 		break;
1811 	}
1812 	mtd->type = MTD_NANDFLASH;
1813 	mtd->flags = MTD_CAP_NANDFLASH;
1814 	mtd->size = (docg3->max_block + 1) * DOC_LAYOUT_BLOCK_SIZE;
1815 	if (docg3->reliable == 2)
1816 		mtd->size /= 2;
1817 	mtd->erasesize = DOC_LAYOUT_BLOCK_SIZE * DOC_LAYOUT_NBPLANES;
1818 	if (docg3->reliable == 2)
1819 		mtd->erasesize /= 2;
1820 	mtd->writesize = DOC_LAYOUT_PAGE_SIZE;
1821 	mtd->oobsize = DOC_LAYOUT_OOB_SIZE;
1822 	mtd->owner = THIS_MODULE;
1823 	mtd->erase = doc_erase;
1824 	mtd->read = doc_read;
1825 	mtd->write = doc_write;
1826 	mtd->read_oob = doc_read_oob;
1827 	mtd->write_oob = doc_write_oob;
1828 	mtd->block_isbad = doc_block_isbad;
1829 	mtd->ecclayout = &docg3_oobinfo;
1830 }
1831 
1832 /**
1833  * doc_probe_device - Check if a device is available
1834  * @base: the io space where the device is probed
1835  * @floor: the floor of the probed device
1836  * @dev: the device
1837  *
1838  * Checks whether a device at the specified IO range, and floor is available.
1839  *
1840  * Returns a mtd_info struct if there is a device, ENODEV if none found, ENOMEM
1841  * if a memory allocation failed. If floor 0 is checked, a reset of the ASIC is
1842  * launched.
1843  */
1844 static struct mtd_info *doc_probe_device(void __iomem *base, int floor,
1845 					 struct device *dev)
1846 {
1847 	int ret, bbt_nbpages;
1848 	u16 chip_id, chip_id_inv;
1849 	struct docg3 *docg3;
1850 	struct mtd_info *mtd;
1851 
1852 	ret = -ENOMEM;
1853 	docg3 = kzalloc(sizeof(struct docg3), GFP_KERNEL);
1854 	if (!docg3)
1855 		goto nomem1;
1856 	mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);
1857 	if (!mtd)
1858 		goto nomem2;
1859 	mtd->priv = docg3;
1860 	bbt_nbpages = DIV_ROUND_UP(docg3->max_block + 1,
1861 				   8 * DOC_LAYOUT_PAGE_SIZE);
1862 	docg3->bbt = kzalloc(bbt_nbpages * DOC_LAYOUT_PAGE_SIZE, GFP_KERNEL);
1863 	if (!docg3->bbt)
1864 		goto nomem3;
1865 
1866 	docg3->dev = dev;
1867 	docg3->device_id = floor;
1868 	docg3->base = base;
1869 	doc_set_device_id(docg3, docg3->device_id);
1870 	if (!floor)
1871 		doc_set_asic_mode(docg3, DOC_ASICMODE_RESET);
1872 	doc_set_asic_mode(docg3, DOC_ASICMODE_NORMAL);
1873 
1874 	chip_id = doc_register_readw(docg3, DOC_CHIPID);
1875 	chip_id_inv = doc_register_readw(docg3, DOC_CHIPID_INV);
1876 
1877 	ret = 0;
1878 	if (chip_id != (u16)(~chip_id_inv)) {
1879 		goto nomem3;
1880 	}
1881 
1882 	switch (chip_id) {
1883 	case DOC_CHIPID_G3:
1884 		doc_info("Found a G3 DiskOnChip at addr %p, floor %d\n",
1885 			 base, floor);
1886 		break;
1887 	default:
1888 		doc_err("Chip id %04x is not a DiskOnChip G3 chip\n", chip_id);
1889 		goto nomem3;
1890 	}
1891 
1892 	doc_set_driver_info(chip_id, mtd);
1893 
1894 	doc_hamming_ecc_init(docg3, DOC_LAYOUT_OOB_PAGEINFO_SZ);
1895 	doc_reload_bbt(docg3);
1896 	return mtd;
1897 
1898 nomem3:
1899 	kfree(mtd);
1900 nomem2:
1901 	kfree(docg3);
1902 nomem1:
1903 	return ERR_PTR(ret);
1904 }
1905 
1906 /**
1907  * doc_release_device - Release a docg3 floor
1908  * @mtd: the device
1909  */
1910 static void doc_release_device(struct mtd_info *mtd)
1911 {
1912 	struct docg3 *docg3 = mtd->priv;
1913 
1914 	mtd_device_unregister(mtd);
1915 	kfree(docg3->bbt);
1916 	kfree(docg3);
1917 	kfree(mtd->name);
1918 	kfree(mtd);
1919 }
1920 
1921 /**
1922  * docg3_resume - Awakens docg3 floor
1923  * @pdev: platfrom device
1924  *
1925  * Returns 0 (always successfull)
1926  */
1927 static int docg3_resume(struct platform_device *pdev)
1928 {
1929 	int i;
1930 	struct mtd_info **docg3_floors, *mtd;
1931 	struct docg3 *docg3;
1932 
1933 	docg3_floors = platform_get_drvdata(pdev);
1934 	mtd = docg3_floors[0];
1935 	docg3 = mtd->priv;
1936 
1937 	doc_dbg("docg3_resume()\n");
1938 	for (i = 0; i < 12; i++)
1939 		doc_readb(docg3, DOC_IOSPACE_IPL);
1940 	return 0;
1941 }
1942 
1943 /**
1944  * docg3_suspend - Put in low power mode the docg3 floor
1945  * @pdev: platform device
1946  * @state: power state
1947  *
1948  * Shuts off most of docg3 circuitery to lower power consumption.
1949  *
1950  * Returns 0 if suspend succeeded, -EIO if chip refused suspend
1951  */
1952 static int docg3_suspend(struct platform_device *pdev, pm_message_t state)
1953 {
1954 	int floor, i;
1955 	struct mtd_info **docg3_floors, *mtd;
1956 	struct docg3 *docg3;
1957 	u8 ctrl, pwr_down;
1958 
1959 	docg3_floors = platform_get_drvdata(pdev);
1960 	for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++) {
1961 		mtd = docg3_floors[floor];
1962 		if (!mtd)
1963 			continue;
1964 		docg3 = mtd->priv;
1965 
1966 		doc_writeb(docg3, floor, DOC_DEVICESELECT);
1967 		ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
1968 		ctrl &= ~DOC_CTRL_VIOLATION & ~DOC_CTRL_CE;
1969 		doc_writeb(docg3, ctrl, DOC_FLASHCONTROL);
1970 
1971 		for (i = 0; i < 10; i++) {
1972 			usleep_range(3000, 4000);
1973 			pwr_down = doc_register_readb(docg3, DOC_POWERMODE);
1974 			if (pwr_down & DOC_POWERDOWN_READY)
1975 				break;
1976 		}
1977 		if (pwr_down & DOC_POWERDOWN_READY) {
1978 			doc_dbg("docg3_suspend(): floor %d powerdown ok\n",
1979 				floor);
1980 		} else {
1981 			doc_err("docg3_suspend(): floor %d powerdown failed\n",
1982 				floor);
1983 			return -EIO;
1984 		}
1985 	}
1986 
1987 	mtd = docg3_floors[0];
1988 	docg3 = mtd->priv;
1989 	doc_set_asic_mode(docg3, DOC_ASICMODE_POWERDOWN);
1990 	return 0;
1991 }
1992 
1993 /**
1994  * doc_probe - Probe the IO space for a DiskOnChip G3 chip
1995  * @pdev: platform device
1996  *
1997  * Probes for a G3 chip at the specified IO space in the platform data
1998  * ressources. The floor 0 must be available.
1999  *
2000  * Returns 0 on success, -ENOMEM, -ENXIO on error
2001  */
2002 static int __init docg3_probe(struct platform_device *pdev)
2003 {
2004 	struct device *dev = &pdev->dev;
2005 	struct mtd_info *mtd;
2006 	struct resource *ress;
2007 	void __iomem *base;
2008 	int ret, floor, found = 0;
2009 	struct mtd_info **docg3_floors;
2010 
2011 	ret = -ENXIO;
2012 	ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2013 	if (!ress) {
2014 		dev_err(dev, "No I/O memory resource defined\n");
2015 		goto noress;
2016 	}
2017 	base = ioremap(ress->start, DOC_IOSPACE_SIZE);
2018 
2019 	ret = -ENOMEM;
2020 	docg3_floors = kzalloc(sizeof(*docg3_floors) * DOC_MAX_NBFLOORS,
2021 			       GFP_KERNEL);
2022 	if (!docg3_floors)
2023 		goto nomem1;
2024 	docg3_bch = init_bch(DOC_ECC_BCH_M, DOC_ECC_BCH_T,
2025 			     DOC_ECC_BCH_PRIMPOLY);
2026 	if (!docg3_bch)
2027 		goto nomem2;
2028 
2029 	for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++) {
2030 		mtd = doc_probe_device(base, floor, dev);
2031 		if (IS_ERR(mtd)) {
2032 			ret = PTR_ERR(mtd);
2033 			goto err_probe;
2034 		}
2035 		if (!mtd) {
2036 			if (floor == 0)
2037 				goto notfound;
2038 			else
2039 				continue;
2040 		}
2041 		docg3_floors[floor] = mtd;
2042 		ret = mtd_device_parse_register(mtd, part_probes, NULL, NULL,
2043 						0);
2044 		if (ret)
2045 			goto err_probe;
2046 		found++;
2047 	}
2048 
2049 	ret = doc_register_sysfs(pdev, docg3_floors);
2050 	if (ret)
2051 		goto err_probe;
2052 	if (!found)
2053 		goto notfound;
2054 
2055 	platform_set_drvdata(pdev, docg3_floors);
2056 	doc_dbg_register(docg3_floors[0]->priv);
2057 	return 0;
2058 
2059 notfound:
2060 	ret = -ENODEV;
2061 	dev_info(dev, "No supported DiskOnChip found\n");
2062 err_probe:
2063 	free_bch(docg3_bch);
2064 	for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++)
2065 		if (docg3_floors[floor])
2066 			doc_release_device(docg3_floors[floor]);
2067 nomem2:
2068 	kfree(docg3_floors);
2069 nomem1:
2070 	iounmap(base);
2071 noress:
2072 	return ret;
2073 }
2074 
2075 /**
2076  * docg3_release - Release the driver
2077  * @pdev: the platform device
2078  *
2079  * Returns 0
2080  */
2081 static int __exit docg3_release(struct platform_device *pdev)
2082 {
2083 	struct mtd_info **docg3_floors = platform_get_drvdata(pdev);
2084 	struct docg3 *docg3 = docg3_floors[0]->priv;
2085 	void __iomem *base = docg3->base;
2086 	int floor;
2087 
2088 	doc_unregister_sysfs(pdev, docg3_floors);
2089 	doc_dbg_unregister(docg3);
2090 	for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++)
2091 		if (docg3_floors[floor])
2092 			doc_release_device(docg3_floors[floor]);
2093 
2094 	kfree(docg3_floors);
2095 	free_bch(docg3_bch);
2096 	iounmap(base);
2097 	return 0;
2098 }
2099 
2100 static struct platform_driver g3_driver = {
2101 	.driver		= {
2102 		.name	= "docg3",
2103 		.owner	= THIS_MODULE,
2104 	},
2105 	.suspend	= docg3_suspend,
2106 	.resume		= docg3_resume,
2107 	.remove		= __exit_p(docg3_release),
2108 };
2109 
2110 static int __init docg3_init(void)
2111 {
2112 	return platform_driver_probe(&g3_driver, docg3_probe);
2113 }
2114 module_init(docg3_init);
2115 
2116 
2117 static void __exit docg3_exit(void)
2118 {
2119 	platform_driver_unregister(&g3_driver);
2120 }
2121 module_exit(docg3_exit);
2122 
2123 MODULE_LICENSE("GPL");
2124 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
2125 MODULE_DESCRIPTION("MTD driver for DiskOnChip G3");
2126