xref: /linux/drivers/mtd/devices/docg3.c (revision 0ea5c948cb64bab5bc7a5516774eb8536f05aa0d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Handles the M-Systems DiskOnChip G3 chip
4  *
5  * Copyright (C) 2011 Robert Jarzmik
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/errno.h>
11 #include <linux/of.h>
12 #include <linux/platform_device.h>
13 #include <linux/string.h>
14 #include <linux/slab.h>
15 #include <linux/io.h>
16 #include <linux/delay.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/mtd/partitions.h>
19 #include <linux/bitmap.h>
20 #include <linux/bitrev.h>
21 #include <linux/bch.h>
22 
23 #include <linux/debugfs.h>
24 #include <linux/seq_file.h>
25 
26 #define CREATE_TRACE_POINTS
27 #include "docg3.h"
28 
29 /*
30  * This driver handles the DiskOnChip G3 flash memory.
31  *
32  * As no specification is available from M-Systems/Sandisk, this drivers lacks
33  * several functions available on the chip, as :
34  *  - IPL write
35  *
36  * The bus data width (8bits versus 16bits) is not handled (if_cfg flag), and
37  * the driver assumes a 16bits data bus.
38  *
39  * DocG3 relies on 2 ECC algorithms, which are handled in hardware :
40  *  - a 1 byte Hamming code stored in the OOB for each page
41  *  - a 7 bytes BCH code stored in the OOB for each page
42  * The BCH ECC is :
43  *  - BCH is in GF(2^14)
44  *  - BCH is over data of 520 bytes (512 page + 7 page_info bytes
45  *                                   + 1 hamming byte)
46  *  - BCH can correct up to 4 bits (t = 4)
47  *  - BCH syndroms are calculated in hardware, and checked in hardware as well
48  *
49  */
50 
51 static unsigned int reliable_mode;
52 module_param(reliable_mode, uint, 0);
53 MODULE_PARM_DESC(reliable_mode, "Set the docg3 mode (0=normal MLC, 1=fast, "
54 		 "2=reliable) : MLC normal operations are in normal mode");
55 
docg3_ooblayout_ecc(struct mtd_info * mtd,int section,struct mtd_oob_region * oobregion)56 static int docg3_ooblayout_ecc(struct mtd_info *mtd, int section,
57 			       struct mtd_oob_region *oobregion)
58 {
59 	if (section)
60 		return -ERANGE;
61 
62 	/* byte 7 is Hamming ECC, byte 8-14 are BCH ECC */
63 	oobregion->offset = 7;
64 	oobregion->length = 8;
65 
66 	return 0;
67 }
68 
docg3_ooblayout_free(struct mtd_info * mtd,int section,struct mtd_oob_region * oobregion)69 static int docg3_ooblayout_free(struct mtd_info *mtd, int section,
70 				struct mtd_oob_region *oobregion)
71 {
72 	if (section > 1)
73 		return -ERANGE;
74 
75 	/* free bytes: byte 0 until byte 6, byte 15 */
76 	if (!section) {
77 		oobregion->offset = 0;
78 		oobregion->length = 7;
79 	} else {
80 		oobregion->offset = 15;
81 		oobregion->length = 1;
82 	}
83 
84 	return 0;
85 }
86 
87 static const struct mtd_ooblayout_ops nand_ooblayout_docg3_ops = {
88 	.ecc = docg3_ooblayout_ecc,
89 	.free = docg3_ooblayout_free,
90 };
91 
doc_readb(struct docg3 * docg3,u16 reg)92 static inline u8 doc_readb(struct docg3 *docg3, u16 reg)
93 {
94 	u8 val = readb(docg3->cascade->base + reg);
95 
96 	trace_docg3_io(0, 8, reg, (int)val);
97 	return val;
98 }
99 
doc_readw(struct docg3 * docg3,u16 reg)100 static inline u16 doc_readw(struct docg3 *docg3, u16 reg)
101 {
102 	u16 val = readw(docg3->cascade->base + reg);
103 
104 	trace_docg3_io(0, 16, reg, (int)val);
105 	return val;
106 }
107 
doc_writeb(struct docg3 * docg3,u8 val,u16 reg)108 static inline void doc_writeb(struct docg3 *docg3, u8 val, u16 reg)
109 {
110 	writeb(val, docg3->cascade->base + reg);
111 	trace_docg3_io(1, 8, reg, val);
112 }
113 
doc_writew(struct docg3 * docg3,u16 val,u16 reg)114 static inline void doc_writew(struct docg3 *docg3, u16 val, u16 reg)
115 {
116 	writew(val, docg3->cascade->base + reg);
117 	trace_docg3_io(1, 16, reg, val);
118 }
119 
doc_flash_command(struct docg3 * docg3,u8 cmd)120 static inline void doc_flash_command(struct docg3 *docg3, u8 cmd)
121 {
122 	doc_writeb(docg3, cmd, DOC_FLASHCOMMAND);
123 }
124 
doc_flash_sequence(struct docg3 * docg3,u8 seq)125 static inline void doc_flash_sequence(struct docg3 *docg3, u8 seq)
126 {
127 	doc_writeb(docg3, seq, DOC_FLASHSEQUENCE);
128 }
129 
doc_flash_address(struct docg3 * docg3,u8 addr)130 static inline void doc_flash_address(struct docg3 *docg3, u8 addr)
131 {
132 	doc_writeb(docg3, addr, DOC_FLASHADDRESS);
133 }
134 
135 static char const * const part_probes[] = { "cmdlinepart", "saftlpart", NULL };
136 
doc_register_readb(struct docg3 * docg3,int reg)137 static int doc_register_readb(struct docg3 *docg3, int reg)
138 {
139 	u8 val;
140 
141 	doc_writew(docg3, reg, DOC_READADDRESS);
142 	val = doc_readb(docg3, reg);
143 	doc_vdbg("Read register %04x : %02x\n", reg, val);
144 	return val;
145 }
146 
doc_register_readw(struct docg3 * docg3,int reg)147 static int doc_register_readw(struct docg3 *docg3, int reg)
148 {
149 	u16 val;
150 
151 	doc_writew(docg3, reg, DOC_READADDRESS);
152 	val = doc_readw(docg3, reg);
153 	doc_vdbg("Read register %04x : %04x\n", reg, val);
154 	return val;
155 }
156 
157 /**
158  * doc_delay - delay docg3 operations
159  * @docg3: the device
160  * @nbNOPs: the number of NOPs to issue
161  *
162  * As no specification is available, the right timings between chip commands are
163  * unknown. The only available piece of information are the observed nops on a
164  * working docg3 chip.
165  * Therefore, doc_delay relies on a busy loop of NOPs, instead of scheduler
166  * friendlier msleep() functions or blocking mdelay().
167  */
doc_delay(struct docg3 * docg3,int nbNOPs)168 static void doc_delay(struct docg3 *docg3, int nbNOPs)
169 {
170 	int i;
171 
172 	doc_vdbg("NOP x %d\n", nbNOPs);
173 	for (i = 0; i < nbNOPs; i++)
174 		doc_writeb(docg3, 0, DOC_NOP);
175 }
176 
is_prot_seq_error(struct docg3 * docg3)177 static int is_prot_seq_error(struct docg3 *docg3)
178 {
179 	int ctrl;
180 
181 	ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
182 	return ctrl & (DOC_CTRL_PROTECTION_ERROR | DOC_CTRL_SEQUENCE_ERROR);
183 }
184 
doc_is_ready(struct docg3 * docg3)185 static int doc_is_ready(struct docg3 *docg3)
186 {
187 	int ctrl;
188 
189 	ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
190 	return ctrl & DOC_CTRL_FLASHREADY;
191 }
192 
doc_wait_ready(struct docg3 * docg3)193 static int doc_wait_ready(struct docg3 *docg3)
194 {
195 	int maxWaitCycles = 100;
196 
197 	do {
198 		doc_delay(docg3, 4);
199 		cpu_relax();
200 	} while (!doc_is_ready(docg3) && maxWaitCycles--);
201 	doc_delay(docg3, 2);
202 	if (maxWaitCycles > 0)
203 		return 0;
204 	else
205 		return -EIO;
206 }
207 
doc_reset_seq(struct docg3 * docg3)208 static int doc_reset_seq(struct docg3 *docg3)
209 {
210 	int ret;
211 
212 	doc_writeb(docg3, 0x10, DOC_FLASHCONTROL);
213 	doc_flash_sequence(docg3, DOC_SEQ_RESET);
214 	doc_flash_command(docg3, DOC_CMD_RESET);
215 	doc_delay(docg3, 2);
216 	ret = doc_wait_ready(docg3);
217 
218 	doc_dbg("doc_reset_seq() -> isReady=%s\n", ret ? "false" : "true");
219 	return ret;
220 }
221 
222 /**
223  * doc_read_data_area - Read data from data area
224  * @docg3: the device
225  * @buf: the buffer to fill in (might be NULL is dummy reads)
226  * @len: the length to read
227  * @first: first time read, DOC_READADDRESS should be set
228  *
229  * Reads bytes from flash data. Handles the single byte / even bytes reads.
230  */
doc_read_data_area(struct docg3 * docg3,void * buf,int len,int first)231 static void doc_read_data_area(struct docg3 *docg3, void *buf, int len,
232 			       int first)
233 {
234 	int i, cdr, len4;
235 	u16 data16, *dst16;
236 	u8 data8, *dst8;
237 
238 	doc_dbg("doc_read_data_area(buf=%p, len=%d)\n", buf, len);
239 	cdr = len & 0x1;
240 	len4 = len - cdr;
241 
242 	if (first)
243 		doc_writew(docg3, DOC_IOSPACE_DATA, DOC_READADDRESS);
244 	dst16 = buf;
245 	for (i = 0; i < len4; i += 2) {
246 		data16 = doc_readw(docg3, DOC_IOSPACE_DATA);
247 		if (dst16) {
248 			*dst16 = data16;
249 			dst16++;
250 		}
251 	}
252 
253 	if (cdr) {
254 		doc_writew(docg3, DOC_IOSPACE_DATA | DOC_READADDR_ONE_BYTE,
255 			   DOC_READADDRESS);
256 		doc_delay(docg3, 1);
257 		dst8 = (u8 *)dst16;
258 		for (i = 0; i < cdr; i++) {
259 			data8 = doc_readb(docg3, DOC_IOSPACE_DATA);
260 			if (dst8) {
261 				*dst8 = data8;
262 				dst8++;
263 			}
264 		}
265 	}
266 }
267 
268 /**
269  * doc_write_data_area - Write data into data area
270  * @docg3: the device
271  * @buf: the buffer to get input bytes from
272  * @len: the length to write
273  *
274  * Writes bytes into flash data. Handles the single byte / even bytes writes.
275  */
doc_write_data_area(struct docg3 * docg3,const void * buf,int len)276 static void doc_write_data_area(struct docg3 *docg3, const void *buf, int len)
277 {
278 	int i, cdr, len4;
279 	u16 *src16;
280 	u8 *src8;
281 
282 	doc_dbg("doc_write_data_area(buf=%p, len=%d)\n", buf, len);
283 	cdr = len & 0x3;
284 	len4 = len - cdr;
285 
286 	doc_writew(docg3, DOC_IOSPACE_DATA, DOC_READADDRESS);
287 	src16 = (u16 *)buf;
288 	for (i = 0; i < len4; i += 2) {
289 		doc_writew(docg3, *src16, DOC_IOSPACE_DATA);
290 		src16++;
291 	}
292 
293 	src8 = (u8 *)src16;
294 	for (i = 0; i < cdr; i++) {
295 		doc_writew(docg3, DOC_IOSPACE_DATA | DOC_READADDR_ONE_BYTE,
296 			   DOC_READADDRESS);
297 		doc_writeb(docg3, *src8, DOC_IOSPACE_DATA);
298 		src8++;
299 	}
300 }
301 
302 /**
303  * doc_set_reliable_mode - Sets the flash to normal or reliable data mode
304  * @docg3: the device
305  *
306  * The reliable data mode is a bit slower than the fast mode, but less errors
307  * occur.  Entering the reliable mode cannot be done without entering the fast
308  * mode first.
309  *
310  * In reliable mode, pages 2*n and 2*n+1 are clones. Writing to page 0 of blocks
311  * (4,5) make the hardware write also to page 1 of blocks blocks(4,5). Reading
312  * from page 0 of blocks (4,5) or from page 1 of blocks (4,5) gives the same
313  * result, which is a logical and between bytes from page 0 and page 1 (which is
314  * consistent with the fact that writing to a page is _clearing_ bits of that
315  * page).
316  */
doc_set_reliable_mode(struct docg3 * docg3)317 static void doc_set_reliable_mode(struct docg3 *docg3)
318 {
319 	static char *strmode[] = { "normal", "fast", "reliable", "invalid" };
320 
321 	doc_dbg("doc_set_reliable_mode(%s)\n", strmode[docg3->reliable]);
322 	switch (docg3->reliable) {
323 	case 0:
324 		break;
325 	case 1:
326 		doc_flash_sequence(docg3, DOC_SEQ_SET_FASTMODE);
327 		doc_flash_command(docg3, DOC_CMD_FAST_MODE);
328 		break;
329 	case 2:
330 		doc_flash_sequence(docg3, DOC_SEQ_SET_RELIABLEMODE);
331 		doc_flash_command(docg3, DOC_CMD_FAST_MODE);
332 		doc_flash_command(docg3, DOC_CMD_RELIABLE_MODE);
333 		break;
334 	default:
335 		doc_err("doc_set_reliable_mode(): invalid mode\n");
336 		break;
337 	}
338 	doc_delay(docg3, 2);
339 }
340 
341 /**
342  * doc_set_asic_mode - Set the ASIC mode
343  * @docg3: the device
344  * @mode: the mode
345  *
346  * The ASIC can work in 3 modes :
347  *  - RESET: all registers are zeroed
348  *  - NORMAL: receives and handles commands
349  *  - POWERDOWN: minimal poweruse, flash parts shut off
350  */
doc_set_asic_mode(struct docg3 * docg3,u8 mode)351 static void doc_set_asic_mode(struct docg3 *docg3, u8 mode)
352 {
353 	int i;
354 
355 	for (i = 0; i < 12; i++)
356 		doc_readb(docg3, DOC_IOSPACE_IPL);
357 
358 	mode |= DOC_ASICMODE_MDWREN;
359 	doc_dbg("doc_set_asic_mode(%02x)\n", mode);
360 	doc_writeb(docg3, mode, DOC_ASICMODE);
361 	doc_writeb(docg3, ~mode, DOC_ASICMODECONFIRM);
362 	doc_delay(docg3, 1);
363 }
364 
365 /**
366  * doc_set_device_id - Sets the devices id for cascaded G3 chips
367  * @docg3: the device
368  * @id: the chip to select (amongst 0, 1, 2, 3)
369  *
370  * There can be 4 cascaded G3 chips. This function selects the one which will
371  * should be the active one.
372  */
doc_set_device_id(struct docg3 * docg3,int id)373 static void doc_set_device_id(struct docg3 *docg3, int id)
374 {
375 	u8 ctrl;
376 
377 	doc_dbg("doc_set_device_id(%d)\n", id);
378 	doc_writeb(docg3, id, DOC_DEVICESELECT);
379 	ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
380 
381 	ctrl &= ~DOC_CTRL_VIOLATION;
382 	ctrl |= DOC_CTRL_CE;
383 	doc_writeb(docg3, ctrl, DOC_FLASHCONTROL);
384 }
385 
386 /**
387  * doc_set_extra_page_mode - Change flash page layout
388  * @docg3: the device
389  *
390  * Normally, the flash page is split into the data (512 bytes) and the out of
391  * band data (16 bytes). For each, 4 more bytes can be accessed, where the wear
392  * leveling counters are stored.  To access this last area of 4 bytes, a special
393  * mode must be input to the flash ASIC.
394  *
395  * Returns 0 if no error occurred, -EIO else.
396  */
doc_set_extra_page_mode(struct docg3 * docg3)397 static int doc_set_extra_page_mode(struct docg3 *docg3)
398 {
399 	int fctrl;
400 
401 	doc_dbg("doc_set_extra_page_mode()\n");
402 	doc_flash_sequence(docg3, DOC_SEQ_PAGE_SIZE_532);
403 	doc_flash_command(docg3, DOC_CMD_PAGE_SIZE_532);
404 	doc_delay(docg3, 2);
405 
406 	fctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
407 	if (fctrl & (DOC_CTRL_PROTECTION_ERROR | DOC_CTRL_SEQUENCE_ERROR))
408 		return -EIO;
409 	else
410 		return 0;
411 }
412 
413 /**
414  * doc_setup_addr_sector - Setup blocks/page/ofs address for one plane
415  * @docg3: the device
416  * @sector: the sector
417  */
doc_setup_addr_sector(struct docg3 * docg3,int sector)418 static void doc_setup_addr_sector(struct docg3 *docg3, int sector)
419 {
420 	doc_delay(docg3, 1);
421 	doc_flash_address(docg3, sector & 0xff);
422 	doc_flash_address(docg3, (sector >> 8) & 0xff);
423 	doc_flash_address(docg3, (sector >> 16) & 0xff);
424 	doc_delay(docg3, 1);
425 }
426 
427 /**
428  * doc_setup_writeaddr_sector - Setup blocks/page/ofs address for one plane
429  * @docg3: the device
430  * @sector: the sector
431  * @ofs: the offset in the page, between 0 and (512 + 16 + 512)
432  */
doc_setup_writeaddr_sector(struct docg3 * docg3,int sector,int ofs)433 static void doc_setup_writeaddr_sector(struct docg3 *docg3, int sector, int ofs)
434 {
435 	ofs = ofs >> 2;
436 	doc_delay(docg3, 1);
437 	doc_flash_address(docg3, ofs & 0xff);
438 	doc_flash_address(docg3, sector & 0xff);
439 	doc_flash_address(docg3, (sector >> 8) & 0xff);
440 	doc_flash_address(docg3, (sector >> 16) & 0xff);
441 	doc_delay(docg3, 1);
442 }
443 
444 /**
445  * doc_read_seek - Set both flash planes to the specified block, page for reading
446  * @docg3: the device
447  * @block0: the first plane block index
448  * @block1: the second plane block index
449  * @page: the page index within the block
450  * @wear: if true, read will occur on the 4 extra bytes of the wear area
451  * @ofs: offset in page to read
452  *
453  * Programs the flash even and odd planes to the specific block and page.
454  * Alternatively, programs the flash to the wear area of the specified page.
455  */
doc_read_seek(struct docg3 * docg3,int block0,int block1,int page,int wear,int ofs)456 static int doc_read_seek(struct docg3 *docg3, int block0, int block1, int page,
457 			 int wear, int ofs)
458 {
459 	int sector, ret = 0;
460 
461 	doc_dbg("doc_seek(blocks=(%d,%d), page=%d, ofs=%d, wear=%d)\n",
462 		block0, block1, page, ofs, wear);
463 
464 	if (!wear && (ofs < 2 * DOC_LAYOUT_PAGE_SIZE)) {
465 		doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE1);
466 		doc_flash_command(docg3, DOC_CMD_READ_PLANE1);
467 		doc_delay(docg3, 2);
468 	} else {
469 		doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE2);
470 		doc_flash_command(docg3, DOC_CMD_READ_PLANE2);
471 		doc_delay(docg3, 2);
472 	}
473 
474 	doc_set_reliable_mode(docg3);
475 	if (wear)
476 		ret = doc_set_extra_page_mode(docg3);
477 	if (ret)
478 		goto out;
479 
480 	doc_flash_sequence(docg3, DOC_SEQ_READ);
481 	sector = (block0 << 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 
485 	sector = (block1 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
486 	doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
487 	doc_setup_addr_sector(docg3, sector);
488 	doc_delay(docg3, 1);
489 
490 out:
491 	return ret;
492 }
493 
494 /**
495  * doc_write_seek - Set both flash planes to the specified block, page for writing
496  * @docg3: the device
497  * @block0: the first plane block index
498  * @block1: the second plane block index
499  * @page: the page index within the block
500  * @ofs: offset in page to write
501  *
502  * Programs the flash even and odd planes to the specific block and page.
503  * Alternatively, programs the flash to the wear area of the specified page.
504  */
doc_write_seek(struct docg3 * docg3,int block0,int block1,int page,int ofs)505 static int doc_write_seek(struct docg3 *docg3, int block0, int block1, int page,
506 			 int ofs)
507 {
508 	int ret = 0, sector;
509 
510 	doc_dbg("doc_write_seek(blocks=(%d,%d), page=%d, ofs=%d)\n",
511 		block0, block1, page, ofs);
512 
513 	doc_set_reliable_mode(docg3);
514 
515 	if (ofs < 2 * DOC_LAYOUT_PAGE_SIZE) {
516 		doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE1);
517 		doc_flash_command(docg3, DOC_CMD_READ_PLANE1);
518 		doc_delay(docg3, 2);
519 	} else {
520 		doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE2);
521 		doc_flash_command(docg3, DOC_CMD_READ_PLANE2);
522 		doc_delay(docg3, 2);
523 	}
524 
525 	doc_flash_sequence(docg3, DOC_SEQ_PAGE_SETUP);
526 	doc_flash_command(docg3, DOC_CMD_PROG_CYCLE1);
527 
528 	sector = (block0 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
529 	doc_setup_writeaddr_sector(docg3, sector, ofs);
530 
531 	doc_flash_command(docg3, DOC_CMD_PROG_CYCLE3);
532 	doc_delay(docg3, 2);
533 	ret = doc_wait_ready(docg3);
534 	if (ret)
535 		goto out;
536 
537 	doc_flash_command(docg3, DOC_CMD_PROG_CYCLE1);
538 	sector = (block1 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
539 	doc_setup_writeaddr_sector(docg3, sector, ofs);
540 	doc_delay(docg3, 1);
541 
542 out:
543 	return ret;
544 }
545 
546 
547 /**
548  * doc_read_page_ecc_init - Initialize hardware ECC engine
549  * @docg3: the device
550  * @len: the number of bytes covered by the ECC (BCH covered)
551  *
552  * The function does initialize the hardware ECC engine to compute the Hamming
553  * ECC (on 1 byte) and the BCH hardware ECC (on 7 bytes).
554  *
555  * Return 0 if succeeded, -EIO on error
556  */
doc_read_page_ecc_init(struct docg3 * docg3,int len)557 static int doc_read_page_ecc_init(struct docg3 *docg3, int len)
558 {
559 	doc_writew(docg3, DOC_ECCCONF0_READ_MODE
560 		   | DOC_ECCCONF0_BCH_ENABLE | DOC_ECCCONF0_HAMMING_ENABLE
561 		   | (len & DOC_ECCCONF0_DATA_BYTES_MASK),
562 		   DOC_ECCCONF0);
563 	doc_delay(docg3, 4);
564 	doc_register_readb(docg3, DOC_FLASHCONTROL);
565 	return doc_wait_ready(docg3);
566 }
567 
568 /**
569  * doc_write_page_ecc_init - Initialize hardware BCH ECC engine
570  * @docg3: the device
571  * @len: the number of bytes covered by the ECC (BCH covered)
572  *
573  * The function does initialize the hardware ECC engine to compute the Hamming
574  * ECC (on 1 byte) and the BCH hardware ECC (on 7 bytes).
575  *
576  * Return 0 if succeeded, -EIO on error
577  */
doc_write_page_ecc_init(struct docg3 * docg3,int len)578 static int doc_write_page_ecc_init(struct docg3 *docg3, int len)
579 {
580 	doc_writew(docg3, DOC_ECCCONF0_WRITE_MODE
581 		   | DOC_ECCCONF0_BCH_ENABLE | DOC_ECCCONF0_HAMMING_ENABLE
582 		   | (len & DOC_ECCCONF0_DATA_BYTES_MASK),
583 		   DOC_ECCCONF0);
584 	doc_delay(docg3, 4);
585 	doc_register_readb(docg3, DOC_FLASHCONTROL);
586 	return doc_wait_ready(docg3);
587 }
588 
589 /**
590  * doc_ecc_disable - Disable Hamming and BCH ECC hardware calculator
591  * @docg3: the device
592  *
593  * Disables the hardware ECC generator and checker, for unchecked reads (as when
594  * reading OOB only or write status byte).
595  */
doc_ecc_disable(struct docg3 * docg3)596 static void doc_ecc_disable(struct docg3 *docg3)
597 {
598 	doc_writew(docg3, DOC_ECCCONF0_READ_MODE, DOC_ECCCONF0);
599 	doc_delay(docg3, 4);
600 }
601 
602 /**
603  * doc_hamming_ecc_init - Initialize hardware Hamming ECC engine
604  * @docg3: the device
605  * @nb_bytes: the number of bytes covered by the ECC (Hamming covered)
606  *
607  * This function programs the ECC hardware to compute the hamming code on the
608  * last provided N bytes to the hardware generator.
609  */
doc_hamming_ecc_init(struct docg3 * docg3,int nb_bytes)610 static void doc_hamming_ecc_init(struct docg3 *docg3, int nb_bytes)
611 {
612 	u8 ecc_conf1;
613 
614 	ecc_conf1 = doc_register_readb(docg3, DOC_ECCCONF1);
615 	ecc_conf1 &= ~DOC_ECCCONF1_HAMMING_BITS_MASK;
616 	ecc_conf1 |= (nb_bytes & DOC_ECCCONF1_HAMMING_BITS_MASK);
617 	doc_writeb(docg3, ecc_conf1, DOC_ECCCONF1);
618 }
619 
620 /**
621  * doc_ecc_bch_fix_data - Fix if need be read data from flash
622  * @docg3: the device
623  * @buf: the buffer of read data (512 + 7 + 1 bytes)
624  * @hwecc: the hardware calculated ECC.
625  *         It's in fact recv_ecc ^ calc_ecc, where recv_ecc was read from OOB
626  *         area data, and calc_ecc the ECC calculated by the hardware generator.
627  *
628  * Checks if the received data matches the ECC, and if an error is detected,
629  * tries to fix the bit flips (at most 4) in the buffer buf.  As the docg3
630  * understands the (data, ecc, syndroms) in an inverted order in comparison to
631  * the BCH library, the function reverses the order of bits (ie. bit7 and bit0,
632  * bit6 and bit 1, ...) for all ECC data.
633  *
634  * The hardware ecc unit produces oob_ecc ^ calc_ecc.  The kernel's bch
635  * algorithm is used to decode this.  However the hw operates on page
636  * data in a bit order that is the reverse of that of the bch alg,
637  * requiring that the bits be reversed on the result.  Thanks to Ivan
638  * Djelic for his analysis.
639  *
640  * Returns number of fixed bits (0, 1, 2, 3, 4) or -EBADMSG if too many bit
641  * errors were detected and cannot be fixed.
642  */
doc_ecc_bch_fix_data(struct docg3 * docg3,void * buf,u8 * hwecc)643 static int doc_ecc_bch_fix_data(struct docg3 *docg3, void *buf, u8 *hwecc)
644 {
645 	u8 ecc[DOC_ECC_BCH_SIZE];
646 	int errorpos[DOC_ECC_BCH_T], i, numerrs;
647 
648 	for (i = 0; i < DOC_ECC_BCH_SIZE; i++)
649 		ecc[i] = bitrev8(hwecc[i]);
650 	numerrs = bch_decode(docg3->cascade->bch, NULL,
651 			     DOC_ECC_BCH_COVERED_BYTES,
652 			     NULL, ecc, NULL, errorpos);
653 	BUG_ON(numerrs == -EINVAL);
654 	if (numerrs < 0)
655 		goto out;
656 
657 	for (i = 0; i < numerrs; i++)
658 		errorpos[i] = (errorpos[i] & ~7) | (7 - (errorpos[i] & 7));
659 	for (i = 0; i < numerrs; i++)
660 		if (errorpos[i] < DOC_ECC_BCH_COVERED_BYTES*8)
661 			/* error is located in data, correct it */
662 			change_bit(errorpos[i], buf);
663 out:
664 	doc_dbg("doc_ecc_bch_fix_data: flipped %d bits\n", numerrs);
665 	return numerrs;
666 }
667 
668 
669 /**
670  * doc_read_page_prepare - Prepares reading data from a flash page
671  * @docg3: the device
672  * @block0: the first plane block index on flash memory
673  * @block1: the second plane block index on flash memory
674  * @page: the page index in the block
675  * @offset: the offset in the page (must be a multiple of 4)
676  *
677  * Prepares the page to be read in the flash memory :
678  *   - tell ASIC to map the flash pages
679  *   - tell ASIC to be in read mode
680  *
681  * After a call to this method, a call to doc_read_page_finish is mandatory,
682  * to end the read cycle of the flash.
683  *
684  * Read data from a flash page. The length to be read must be between 0 and
685  * (page_size + oob_size + wear_size), ie. 532, and a multiple of 4 (because
686  * the extra bytes reading is not implemented).
687  *
688  * As pages are grouped by 2 (in 2 planes), reading from a page must be done
689  * in two steps:
690  *  - one read of 512 bytes at offset 0
691  *  - one read of 512 bytes at offset 512 + 16
692  *
693  * Returns 0 if successful, -EIO if a read error occurred.
694  */
doc_read_page_prepare(struct docg3 * docg3,int block0,int block1,int page,int offset)695 static int doc_read_page_prepare(struct docg3 *docg3, int block0, int block1,
696 				 int page, int offset)
697 {
698 	int wear_area = 0, ret = 0;
699 
700 	doc_dbg("doc_read_page_prepare(blocks=(%d,%d), page=%d, ofsInPage=%d)\n",
701 		block0, block1, page, offset);
702 	if (offset >= DOC_LAYOUT_WEAR_OFFSET)
703 		wear_area = 1;
704 	if (!wear_area && offset > (DOC_LAYOUT_PAGE_OOB_SIZE * 2))
705 		return -EINVAL;
706 
707 	doc_set_device_id(docg3, docg3->device_id);
708 	ret = doc_reset_seq(docg3);
709 	if (ret)
710 		goto err;
711 
712 	/* Program the flash address block and page */
713 	ret = doc_read_seek(docg3, block0, block1, page, wear_area, offset);
714 	if (ret)
715 		goto err;
716 
717 	doc_flash_command(docg3, DOC_CMD_READ_ALL_PLANES);
718 	doc_delay(docg3, 2);
719 	doc_wait_ready(docg3);
720 
721 	doc_flash_command(docg3, DOC_CMD_SET_ADDR_READ);
722 	doc_delay(docg3, 1);
723 	if (offset >= DOC_LAYOUT_PAGE_SIZE * 2)
724 		offset -= 2 * DOC_LAYOUT_PAGE_SIZE;
725 	doc_flash_address(docg3, offset >> 2);
726 	doc_delay(docg3, 1);
727 	doc_wait_ready(docg3);
728 
729 	doc_flash_command(docg3, DOC_CMD_READ_FLASH);
730 
731 	return 0;
732 err:
733 	doc_writeb(docg3, 0, DOC_DATAEND);
734 	doc_delay(docg3, 2);
735 	return -EIO;
736 }
737 
738 /**
739  * doc_read_page_getbytes - Reads bytes from a prepared page
740  * @docg3: the device
741  * @len: the number of bytes to be read (must be a multiple of 4)
742  * @buf: the buffer to be filled in (or NULL is forget bytes)
743  * @first: 1 if first time read, DOC_READADDRESS should be set
744  * @last_odd: 1 if last read ended up on an odd byte
745  *
746  * Reads bytes from a prepared page. There is a trickery here : if the last read
747  * ended up on an odd offset in the 1024 bytes double page, ie. between the 2
748  * planes, the first byte must be read apart. If a word (16bit) read was used,
749  * the read would return the byte of plane 2 as low *and* high endian, which
750  * will mess the read.
751  *
752  */
doc_read_page_getbytes(struct docg3 * docg3,int len,u_char * buf,int first,int last_odd)753 static int doc_read_page_getbytes(struct docg3 *docg3, int len, u_char *buf,
754 				  int first, int last_odd)
755 {
756 	if (last_odd && len > 0) {
757 		doc_read_data_area(docg3, buf, 1, first);
758 		doc_read_data_area(docg3, buf ? buf + 1 : buf, len - 1, 0);
759 	} else {
760 		doc_read_data_area(docg3, buf, len, first);
761 	}
762 	doc_delay(docg3, 2);
763 	return len;
764 }
765 
766 /**
767  * doc_write_page_putbytes - Writes bytes into a prepared page
768  * @docg3: the device
769  * @len: the number of bytes to be written
770  * @buf: the buffer of input bytes
771  *
772  */
doc_write_page_putbytes(struct docg3 * docg3,int len,const u_char * buf)773 static void doc_write_page_putbytes(struct docg3 *docg3, int len,
774 				    const u_char *buf)
775 {
776 	doc_write_data_area(docg3, buf, len);
777 	doc_delay(docg3, 2);
778 }
779 
780 /**
781  * doc_get_bch_hw_ecc - Get hardware calculated BCH ECC
782  * @docg3: the device
783  * @hwecc:  the array of 7 integers where the hardware ecc will be stored
784  */
doc_get_bch_hw_ecc(struct docg3 * docg3,u8 * hwecc)785 static void doc_get_bch_hw_ecc(struct docg3 *docg3, u8 *hwecc)
786 {
787 	int i;
788 
789 	for (i = 0; i < DOC_ECC_BCH_SIZE; i++)
790 		hwecc[i] = doc_register_readb(docg3, DOC_BCH_HW_ECC(i));
791 }
792 
793 /**
794  * doc_page_finish - Ends reading/writing of a flash page
795  * @docg3: the device
796  */
doc_page_finish(struct docg3 * docg3)797 static void doc_page_finish(struct docg3 *docg3)
798 {
799 	doc_writeb(docg3, 0, DOC_DATAEND);
800 	doc_delay(docg3, 2);
801 }
802 
803 /**
804  * doc_read_page_finish - Ends reading of a flash page
805  * @docg3: the device
806  *
807  * As a side effect, resets the chip selector to 0. This ensures that after each
808  * read operation, the floor 0 is selected. Therefore, if the systems halts, the
809  * reboot will boot on floor 0, where the IPL is.
810  */
doc_read_page_finish(struct docg3 * docg3)811 static void doc_read_page_finish(struct docg3 *docg3)
812 {
813 	doc_page_finish(docg3);
814 	doc_set_device_id(docg3, 0);
815 }
816 
817 /**
818  * calc_block_sector - Calculate blocks, pages and ofs.
819  *
820  * @from: offset in flash
821  * @block0: first plane block index calculated
822  * @block1: second plane block index calculated
823  * @page: page calculated
824  * @ofs: offset in page
825  * @reliable: 0 if docg3 in normal mode, 1 if docg3 in fast mode, 2 if docg3 in
826  * reliable mode.
827  *
828  * The calculation is based on the reliable/normal mode. In normal mode, the 64
829  * pages of a block are available. In reliable mode, as pages 2*n and 2*n+1 are
830  * clones, only 32 pages per block are available.
831  */
calc_block_sector(loff_t from,int * block0,int * block1,int * page,int * ofs,int reliable)832 static void calc_block_sector(loff_t from, int *block0, int *block1, int *page,
833 			      int *ofs, int reliable)
834 {
835 	uint sector, pages_biblock;
836 
837 	pages_biblock = DOC_LAYOUT_PAGES_PER_BLOCK * DOC_LAYOUT_NBPLANES;
838 	if (reliable == 1 || reliable == 2)
839 		pages_biblock /= 2;
840 
841 	sector = from / DOC_LAYOUT_PAGE_SIZE;
842 	*block0 = sector / pages_biblock * DOC_LAYOUT_NBPLANES;
843 	*block1 = *block0 + 1;
844 	*page = sector % pages_biblock;
845 	*page /= DOC_LAYOUT_NBPLANES;
846 	if (reliable == 1 || reliable == 2)
847 		*page *= 2;
848 	if (sector % 2)
849 		*ofs = DOC_LAYOUT_PAGE_OOB_SIZE;
850 	else
851 		*ofs = 0;
852 }
853 
854 /**
855  * doc_read_oob - Read out of band bytes from flash
856  * @mtd: the device
857  * @from: the offset from first block and first page, in bytes, aligned on page
858  *        size
859  * @ops: the mtd oob structure
860  *
861  * Reads flash memory OOB area of pages.
862  *
863  * Returns 0 if read successful, of -EIO, -EINVAL if an error occurred
864  */
doc_read_oob(struct mtd_info * mtd,loff_t from,struct mtd_oob_ops * ops)865 static int doc_read_oob(struct mtd_info *mtd, loff_t from,
866 			struct mtd_oob_ops *ops)
867 {
868 	struct docg3 *docg3 = mtd->priv;
869 	int block0, block1, page, ret, skip, ofs = 0;
870 	u8 *oobbuf = ops->oobbuf;
871 	u8 *buf = ops->datbuf;
872 	size_t len, ooblen, nbdata, nboob;
873 	u8 hwecc[DOC_ECC_BCH_SIZE], eccconf1;
874 	struct mtd_ecc_stats old_stats;
875 	int max_bitflips = 0;
876 
877 	if (buf)
878 		len = ops->len;
879 	else
880 		len = 0;
881 	if (oobbuf)
882 		ooblen = ops->ooblen;
883 	else
884 		ooblen = 0;
885 
886 	if (oobbuf && ops->mode == MTD_OPS_PLACE_OOB)
887 		oobbuf += ops->ooboffs;
888 
889 	doc_dbg("doc_read_oob(from=%lld, mode=%d, data=(%p:%zu), oob=(%p:%zu))\n",
890 		from, ops->mode, buf, len, oobbuf, ooblen);
891 	if (ooblen % DOC_LAYOUT_OOB_SIZE)
892 		return -EINVAL;
893 
894 	ops->oobretlen = 0;
895 	ops->retlen = 0;
896 	ret = 0;
897 	skip = from % DOC_LAYOUT_PAGE_SIZE;
898 	mutex_lock(&docg3->cascade->lock);
899 	old_stats = mtd->ecc_stats;
900 	while (ret >= 0 && (len > 0 || ooblen > 0)) {
901 		calc_block_sector(from - skip, &block0, &block1, &page, &ofs,
902 			docg3->reliable);
903 		nbdata = min_t(size_t, len, DOC_LAYOUT_PAGE_SIZE - skip);
904 		nboob = min_t(size_t, ooblen, (size_t)DOC_LAYOUT_OOB_SIZE);
905 		ret = doc_read_page_prepare(docg3, block0, block1, page, ofs);
906 		if (ret < 0)
907 			goto out;
908 		ret = doc_read_page_ecc_init(docg3, DOC_ECC_BCH_TOTAL_BYTES);
909 		if (ret < 0)
910 			goto err_in_read;
911 		ret = doc_read_page_getbytes(docg3, skip, NULL, 1, 0);
912 		if (ret < skip)
913 			goto err_in_read;
914 		ret = doc_read_page_getbytes(docg3, nbdata, buf, 0, skip % 2);
915 		if (ret < nbdata)
916 			goto err_in_read;
917 		doc_read_page_getbytes(docg3,
918 				       DOC_LAYOUT_PAGE_SIZE - nbdata - skip,
919 				       NULL, 0, (skip + nbdata) % 2);
920 		ret = doc_read_page_getbytes(docg3, nboob, oobbuf, 0, 0);
921 		if (ret < nboob)
922 			goto err_in_read;
923 		doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE - nboob,
924 				       NULL, 0, nboob % 2);
925 
926 		doc_get_bch_hw_ecc(docg3, hwecc);
927 		eccconf1 = doc_register_readb(docg3, DOC_ECCCONF1);
928 
929 		if (nboob >= DOC_LAYOUT_OOB_SIZE) {
930 			doc_dbg("OOB - INFO: %*phC\n", 7, oobbuf);
931 			doc_dbg("OOB - HAMMING: %02x\n", oobbuf[7]);
932 			doc_dbg("OOB - BCH_ECC: %*phC\n", 7, oobbuf + 8);
933 			doc_dbg("OOB - UNUSED: %02x\n", oobbuf[15]);
934 		}
935 		doc_dbg("ECC checks: ECCConf1=%x\n", eccconf1);
936 		doc_dbg("ECC HW_ECC: %*phC\n", 7, hwecc);
937 
938 		ret = -EIO;
939 		if (is_prot_seq_error(docg3))
940 			goto err_in_read;
941 		ret = 0;
942 		if ((block0 >= DOC_LAYOUT_BLOCK_FIRST_DATA) &&
943 		    (eccconf1 & DOC_ECCCONF1_BCH_SYNDROM_ERR) &&
944 		    (eccconf1 & DOC_ECCCONF1_PAGE_IS_WRITTEN) &&
945 		    (ops->mode != MTD_OPS_RAW) &&
946 		    (nbdata == DOC_LAYOUT_PAGE_SIZE)) {
947 			ret = doc_ecc_bch_fix_data(docg3, buf, hwecc);
948 			if (ret < 0) {
949 				mtd->ecc_stats.failed++;
950 				ret = -EBADMSG;
951 			}
952 			if (ret > 0) {
953 				mtd->ecc_stats.corrected += ret;
954 				max_bitflips = max(max_bitflips, ret);
955 				ret = max_bitflips;
956 			}
957 		}
958 
959 		doc_read_page_finish(docg3);
960 		ops->retlen += nbdata;
961 		ops->oobretlen += nboob;
962 		buf += nbdata;
963 		oobbuf += nboob;
964 		len -= nbdata;
965 		ooblen -= nboob;
966 		from += DOC_LAYOUT_PAGE_SIZE;
967 		skip = 0;
968 	}
969 
970 out:
971 	if (ops->stats) {
972 		ops->stats->uncorrectable_errors +=
973 			mtd->ecc_stats.failed - old_stats.failed;
974 		ops->stats->corrected_bitflips +=
975 			mtd->ecc_stats.corrected - old_stats.corrected;
976 	}
977 	mutex_unlock(&docg3->cascade->lock);
978 	return ret;
979 err_in_read:
980 	doc_read_page_finish(docg3);
981 	goto out;
982 }
983 
doc_reload_bbt(struct docg3 * docg3)984 static int doc_reload_bbt(struct docg3 *docg3)
985 {
986 	int block = DOC_LAYOUT_BLOCK_BBT;
987 	int ret = 0, nbpages, page;
988 	u_char *buf = docg3->bbt;
989 
990 	nbpages = DIV_ROUND_UP(docg3->max_block + 1, 8 * DOC_LAYOUT_PAGE_SIZE);
991 	for (page = 0; !ret && (page < nbpages); page++) {
992 		ret = doc_read_page_prepare(docg3, block, block + 1,
993 					    page + DOC_LAYOUT_PAGE_BBT, 0);
994 		if (!ret)
995 			ret = doc_read_page_ecc_init(docg3,
996 						     DOC_LAYOUT_PAGE_SIZE);
997 		if (!ret)
998 			doc_read_page_getbytes(docg3, DOC_LAYOUT_PAGE_SIZE,
999 					       buf, 1, 0);
1000 		buf += DOC_LAYOUT_PAGE_SIZE;
1001 	}
1002 	doc_read_page_finish(docg3);
1003 	return ret;
1004 }
1005 
1006 /**
1007  * doc_block_isbad - Checks whether a block is good or not
1008  * @mtd: the device
1009  * @from: the offset to find the correct block
1010  *
1011  * Returns 1 if block is bad, 0 if block is good
1012  */
doc_block_isbad(struct mtd_info * mtd,loff_t from)1013 static int doc_block_isbad(struct mtd_info *mtd, loff_t from)
1014 {
1015 	struct docg3 *docg3 = mtd->priv;
1016 	int block0, block1, page, ofs, is_good;
1017 
1018 	calc_block_sector(from, &block0, &block1, &page, &ofs,
1019 		docg3->reliable);
1020 	doc_dbg("doc_block_isbad(from=%lld) => block=(%d,%d), page=%d, ofs=%d\n",
1021 		from, block0, block1, page, ofs);
1022 
1023 	if (block0 < DOC_LAYOUT_BLOCK_FIRST_DATA)
1024 		return 0;
1025 	if (block1 > docg3->max_block)
1026 		return -EINVAL;
1027 
1028 	is_good = docg3->bbt[block0 >> 3] & (1 << (block0 & 0x7));
1029 	return !is_good;
1030 }
1031 
1032 #if 0
1033 /**
1034  * doc_get_erase_count - Get block erase count
1035  * @docg3: the device
1036  * @from: the offset in which the block is.
1037  *
1038  * Get the number of times a block was erased. The number is the maximum of
1039  * erase times between first and second plane (which should be equal normally).
1040  *
1041  * Returns The number of erases, or -EINVAL or -EIO on error.
1042  */
1043 static int doc_get_erase_count(struct docg3 *docg3, loff_t from)
1044 {
1045 	u8 buf[DOC_LAYOUT_WEAR_SIZE];
1046 	int ret, plane1_erase_count, plane2_erase_count;
1047 	int block0, block1, page, ofs;
1048 
1049 	doc_dbg("doc_get_erase_count(from=%lld, buf=%p)\n", from, buf);
1050 	if (from % DOC_LAYOUT_PAGE_SIZE)
1051 		return -EINVAL;
1052 	calc_block_sector(from, &block0, &block1, &page, &ofs, docg3->reliable);
1053 	if (block1 > docg3->max_block)
1054 		return -EINVAL;
1055 
1056 	ret = doc_reset_seq(docg3);
1057 	if (!ret)
1058 		ret = doc_read_page_prepare(docg3, block0, block1, page,
1059 					    ofs + DOC_LAYOUT_WEAR_OFFSET, 0);
1060 	if (!ret)
1061 		ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_WEAR_SIZE,
1062 					     buf, 1, 0);
1063 	doc_read_page_finish(docg3);
1064 
1065 	if (ret || (buf[0] != DOC_ERASE_MARK) || (buf[2] != DOC_ERASE_MARK))
1066 		return -EIO;
1067 	plane1_erase_count = (u8)(~buf[1]) | ((u8)(~buf[4]) << 8)
1068 		| ((u8)(~buf[5]) << 16);
1069 	plane2_erase_count = (u8)(~buf[3]) | ((u8)(~buf[6]) << 8)
1070 		| ((u8)(~buf[7]) << 16);
1071 
1072 	return max(plane1_erase_count, plane2_erase_count);
1073 }
1074 #endif
1075 
1076 /**
1077  * doc_get_op_status - get erase/write operation status
1078  * @docg3: the device
1079  *
1080  * Queries the status from the chip, and returns it
1081  *
1082  * Returns the status (bits DOC_PLANES_STATUS_*)
1083  */
doc_get_op_status(struct docg3 * docg3)1084 static int doc_get_op_status(struct docg3 *docg3)
1085 {
1086 	u8 status;
1087 
1088 	doc_flash_sequence(docg3, DOC_SEQ_PLANES_STATUS);
1089 	doc_flash_command(docg3, DOC_CMD_PLANES_STATUS);
1090 	doc_delay(docg3, 5);
1091 
1092 	doc_ecc_disable(docg3);
1093 	doc_read_data_area(docg3, &status, 1, 1);
1094 	return status;
1095 }
1096 
1097 /**
1098  * doc_write_erase_wait_status - wait for write or erase completion
1099  * @docg3: the device
1100  *
1101  * Wait for the chip to be ready again after erase or write operation, and check
1102  * erase/write status.
1103  *
1104  * Returns 0 if erase successful, -EIO if erase/write issue, -ETIMEOUT if
1105  * timeout
1106  */
doc_write_erase_wait_status(struct docg3 * docg3)1107 static int doc_write_erase_wait_status(struct docg3 *docg3)
1108 {
1109 	int i, status, ret = 0;
1110 
1111 	for (i = 0; !doc_is_ready(docg3) && i < 5; i++)
1112 		msleep(20);
1113 	if (!doc_is_ready(docg3)) {
1114 		doc_dbg("Timeout reached and the chip is still not ready\n");
1115 		ret = -EAGAIN;
1116 		goto out;
1117 	}
1118 
1119 	status = doc_get_op_status(docg3);
1120 	if (status & DOC_PLANES_STATUS_FAIL) {
1121 		doc_dbg("Erase/Write failed on (a) plane(s), status = %x\n",
1122 			status);
1123 		ret = -EIO;
1124 	}
1125 
1126 out:
1127 	doc_page_finish(docg3);
1128 	return ret;
1129 }
1130 
1131 /**
1132  * doc_erase_block - Erase a couple of blocks
1133  * @docg3: the device
1134  * @block0: the first block to erase (leftmost plane)
1135  * @block1: the second block to erase (rightmost plane)
1136  *
1137  * Erase both blocks, and return operation status
1138  *
1139  * Returns 0 if erase successful, -EIO if erase issue, -ETIMEOUT if chip not
1140  * ready for too long
1141  */
doc_erase_block(struct docg3 * docg3,int block0,int block1)1142 static int doc_erase_block(struct docg3 *docg3, int block0, int block1)
1143 {
1144 	int ret, sector;
1145 
1146 	doc_dbg("doc_erase_block(blocks=(%d,%d))\n", block0, block1);
1147 	ret = doc_reset_seq(docg3);
1148 	if (ret)
1149 		return -EIO;
1150 
1151 	doc_set_reliable_mode(docg3);
1152 	doc_flash_sequence(docg3, DOC_SEQ_ERASE);
1153 
1154 	sector = block0 << DOC_ADDR_BLOCK_SHIFT;
1155 	doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
1156 	doc_setup_addr_sector(docg3, sector);
1157 	sector = block1 << DOC_ADDR_BLOCK_SHIFT;
1158 	doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
1159 	doc_setup_addr_sector(docg3, sector);
1160 	doc_delay(docg3, 1);
1161 
1162 	doc_flash_command(docg3, DOC_CMD_ERASECYCLE2);
1163 	doc_delay(docg3, 2);
1164 
1165 	if (is_prot_seq_error(docg3)) {
1166 		doc_err("Erase blocks %d,%d error\n", block0, block1);
1167 		return -EIO;
1168 	}
1169 
1170 	return doc_write_erase_wait_status(docg3);
1171 }
1172 
1173 /**
1174  * doc_erase - Erase a portion of the chip
1175  * @mtd: the device
1176  * @info: the erase info
1177  *
1178  * Erase a bunch of contiguous blocks, by pairs, as a "mtd" page of 1024 is
1179  * split into 2 pages of 512 bytes on 2 contiguous blocks.
1180  *
1181  * Returns 0 if erase successful, -EINVAL if addressing error, -EIO if erase
1182  * issue
1183  */
doc_erase(struct mtd_info * mtd,struct erase_info * info)1184 static int doc_erase(struct mtd_info *mtd, struct erase_info *info)
1185 {
1186 	struct docg3 *docg3 = mtd->priv;
1187 	uint64_t len;
1188 	int block0, block1, page, ret = 0, ofs = 0;
1189 
1190 	doc_dbg("doc_erase(from=%lld, len=%lld\n", info->addr, info->len);
1191 
1192 	calc_block_sector(info->addr + info->len, &block0, &block1, &page,
1193 			  &ofs, docg3->reliable);
1194 	if (info->addr + info->len > mtd->size || page || ofs)
1195 		return -EINVAL;
1196 
1197 	calc_block_sector(info->addr, &block0, &block1, &page, &ofs,
1198 			  docg3->reliable);
1199 	mutex_lock(&docg3->cascade->lock);
1200 	doc_set_device_id(docg3, docg3->device_id);
1201 	doc_set_reliable_mode(docg3);
1202 	for (len = info->len; !ret && len > 0; len -= mtd->erasesize) {
1203 		ret = doc_erase_block(docg3, block0, block1);
1204 		block0 += 2;
1205 		block1 += 2;
1206 	}
1207 	mutex_unlock(&docg3->cascade->lock);
1208 
1209 	return ret;
1210 }
1211 
1212 /**
1213  * doc_write_page - Write a single page to the chip
1214  * @docg3: the device
1215  * @to: the offset from first block and first page, in bytes, aligned on page
1216  *      size
1217  * @buf: buffer to get bytes from
1218  * @oob: buffer to get out of band bytes from (can be NULL if no OOB should be
1219  *       written)
1220  * @autoecc: if 0, all 16 bytes from OOB are taken, regardless of HW Hamming or
1221  *           BCH computations. If 1, only bytes 0-7 and byte 15 are taken,
1222  *           remaining ones are filled with hardware Hamming and BCH
1223  *           computations. Its value is not meaningfull is oob == NULL.
1224  *
1225  * Write one full page (ie. 1 page split on two planes), of 512 bytes, with the
1226  * OOB data. The OOB ECC is automatically computed by the hardware Hamming and
1227  * BCH generator if autoecc is not null.
1228  *
1229  * Returns 0 if write successful, -EIO if write error, -EAGAIN if timeout
1230  */
doc_write_page(struct docg3 * docg3,loff_t to,const u_char * buf,const u_char * oob,int autoecc)1231 static int doc_write_page(struct docg3 *docg3, loff_t to, const u_char *buf,
1232 			  const u_char *oob, int autoecc)
1233 {
1234 	int block0, block1, page, ret, ofs = 0;
1235 	u8 hwecc[DOC_ECC_BCH_SIZE], hamming;
1236 
1237 	doc_dbg("doc_write_page(to=%lld)\n", to);
1238 	calc_block_sector(to, &block0, &block1, &page, &ofs, docg3->reliable);
1239 
1240 	doc_set_device_id(docg3, docg3->device_id);
1241 	ret = doc_reset_seq(docg3);
1242 	if (ret)
1243 		goto err;
1244 
1245 	/* Program the flash address block and page */
1246 	ret = doc_write_seek(docg3, block0, block1, page, ofs);
1247 	if (ret)
1248 		goto err;
1249 
1250 	doc_write_page_ecc_init(docg3, DOC_ECC_BCH_TOTAL_BYTES);
1251 	doc_delay(docg3, 2);
1252 	doc_write_page_putbytes(docg3, DOC_LAYOUT_PAGE_SIZE, buf);
1253 
1254 	if (oob && autoecc) {
1255 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_PAGEINFO_SZ, oob);
1256 		doc_delay(docg3, 2);
1257 		oob += DOC_LAYOUT_OOB_UNUSED_OFS;
1258 
1259 		hamming = doc_register_readb(docg3, DOC_HAMMINGPARITY);
1260 		doc_delay(docg3, 2);
1261 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_HAMMING_SZ,
1262 					&hamming);
1263 		doc_delay(docg3, 2);
1264 
1265 		doc_get_bch_hw_ecc(docg3, hwecc);
1266 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_BCH_SZ, hwecc);
1267 		doc_delay(docg3, 2);
1268 
1269 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_UNUSED_SZ, oob);
1270 	}
1271 	if (oob && !autoecc)
1272 		doc_write_page_putbytes(docg3, DOC_LAYOUT_OOB_SIZE, oob);
1273 
1274 	doc_delay(docg3, 2);
1275 	doc_page_finish(docg3);
1276 	doc_delay(docg3, 2);
1277 	doc_flash_command(docg3, DOC_CMD_PROG_CYCLE2);
1278 	doc_delay(docg3, 2);
1279 
1280 	/*
1281 	 * The wait status will perform another doc_page_finish() call, but that
1282 	 * seems to please the docg3, so leave it.
1283 	 */
1284 	ret = doc_write_erase_wait_status(docg3);
1285 	return ret;
1286 err:
1287 	doc_read_page_finish(docg3);
1288 	return ret;
1289 }
1290 
1291 /**
1292  * doc_guess_autoecc - Guess autoecc mode from mbd_oob_ops
1293  * @ops: the oob operations
1294  *
1295  * Returns 0 or 1 if success, -EINVAL if invalid oob mode
1296  */
doc_guess_autoecc(struct mtd_oob_ops * ops)1297 static int doc_guess_autoecc(struct mtd_oob_ops *ops)
1298 {
1299 	int autoecc;
1300 
1301 	switch (ops->mode) {
1302 	case MTD_OPS_PLACE_OOB:
1303 	case MTD_OPS_AUTO_OOB:
1304 		autoecc = 1;
1305 		break;
1306 	case MTD_OPS_RAW:
1307 		autoecc = 0;
1308 		break;
1309 	default:
1310 		autoecc = -EINVAL;
1311 	}
1312 	return autoecc;
1313 }
1314 
1315 /**
1316  * doc_fill_autooob - Fill a 16 bytes OOB from 8 non-ECC bytes
1317  * @dst: the target 16 bytes OOB buffer
1318  * @oobsrc: the source 8 bytes non-ECC OOB buffer
1319  *
1320  */
doc_fill_autooob(u8 * dst,u8 * oobsrc)1321 static void doc_fill_autooob(u8 *dst, u8 *oobsrc)
1322 {
1323 	memcpy(dst, oobsrc, DOC_LAYOUT_OOB_PAGEINFO_SZ);
1324 	dst[DOC_LAYOUT_OOB_UNUSED_OFS] = oobsrc[DOC_LAYOUT_OOB_PAGEINFO_SZ];
1325 }
1326 
1327 /**
1328  * doc_backup_oob - Backup OOB into docg3 structure
1329  * @docg3: the device
1330  * @to: the page offset in the chip
1331  * @ops: the OOB size and buffer
1332  *
1333  * As the docg3 should write a page with its OOB in one pass, and some userland
1334  * applications do write_oob() to setup the OOB and then write(), store the OOB
1335  * into a temporary storage. This is very dangerous, as 2 concurrent
1336  * applications could store an OOB, and then write their pages (which will
1337  * result into one having its OOB corrupted).
1338  *
1339  * The only reliable way would be for userland to call doc_write_oob() with both
1340  * the page data _and_ the OOB area.
1341  *
1342  * Returns 0 if success, -EINVAL if ops content invalid
1343  */
doc_backup_oob(struct docg3 * docg3,loff_t to,struct mtd_oob_ops * ops)1344 static int doc_backup_oob(struct docg3 *docg3, loff_t to,
1345 			  struct mtd_oob_ops *ops)
1346 {
1347 	int ooblen = ops->ooblen, autoecc;
1348 
1349 	if (ooblen != DOC_LAYOUT_OOB_SIZE)
1350 		return -EINVAL;
1351 	autoecc = doc_guess_autoecc(ops);
1352 	if (autoecc < 0)
1353 		return autoecc;
1354 
1355 	docg3->oob_write_ofs = to;
1356 	docg3->oob_autoecc = autoecc;
1357 	if (ops->mode == MTD_OPS_AUTO_OOB) {
1358 		doc_fill_autooob(docg3->oob_write_buf, ops->oobbuf);
1359 		ops->oobretlen = 8;
1360 	} else {
1361 		memcpy(docg3->oob_write_buf, ops->oobbuf, DOC_LAYOUT_OOB_SIZE);
1362 		ops->oobretlen = DOC_LAYOUT_OOB_SIZE;
1363 	}
1364 	return 0;
1365 }
1366 
1367 /**
1368  * doc_write_oob - Write out of band bytes to flash
1369  * @mtd: the device
1370  * @ofs: the offset from first block and first page, in bytes, aligned on page
1371  *       size
1372  * @ops: the mtd oob structure
1373  *
1374  * Either write OOB data into a temporary buffer, for the subsequent write
1375  * page. The provided OOB should be 16 bytes long. If a data buffer is provided
1376  * as well, issue the page write.
1377  * Or provide data without OOB, and then a all zeroed OOB will be used (ECC will
1378  * still be filled in if asked for).
1379  *
1380  * Returns 0 is successful, EINVAL if length is not 14 bytes
1381  */
doc_write_oob(struct mtd_info * mtd,loff_t ofs,struct mtd_oob_ops * ops)1382 static int doc_write_oob(struct mtd_info *mtd, loff_t ofs,
1383 			 struct mtd_oob_ops *ops)
1384 {
1385 	struct docg3 *docg3 = mtd->priv;
1386 	int ret, autoecc, oobdelta;
1387 	u8 *oobbuf = ops->oobbuf;
1388 	u8 *buf = ops->datbuf;
1389 	size_t len, ooblen;
1390 	u8 oob[DOC_LAYOUT_OOB_SIZE];
1391 
1392 	if (buf)
1393 		len = ops->len;
1394 	else
1395 		len = 0;
1396 	if (oobbuf)
1397 		ooblen = ops->ooblen;
1398 	else
1399 		ooblen = 0;
1400 
1401 	if (oobbuf && ops->mode == MTD_OPS_PLACE_OOB)
1402 		oobbuf += ops->ooboffs;
1403 
1404 	doc_dbg("doc_write_oob(from=%lld, mode=%d, data=(%p:%zu), oob=(%p:%zu))\n",
1405 		ofs, ops->mode, buf, len, oobbuf, ooblen);
1406 	switch (ops->mode) {
1407 	case MTD_OPS_PLACE_OOB:
1408 	case MTD_OPS_RAW:
1409 		oobdelta = mtd->oobsize;
1410 		break;
1411 	case MTD_OPS_AUTO_OOB:
1412 		oobdelta = mtd->oobavail;
1413 		break;
1414 	default:
1415 		return -EINVAL;
1416 	}
1417 	if ((len % DOC_LAYOUT_PAGE_SIZE) || (ooblen % oobdelta) ||
1418 	    (ofs % DOC_LAYOUT_PAGE_SIZE))
1419 		return -EINVAL;
1420 	if (len && ooblen &&
1421 	    (len / DOC_LAYOUT_PAGE_SIZE) != (ooblen / oobdelta))
1422 		return -EINVAL;
1423 
1424 	ops->oobretlen = 0;
1425 	ops->retlen = 0;
1426 	ret = 0;
1427 	if (len == 0 && ooblen == 0)
1428 		return -EINVAL;
1429 	if (len == 0 && ooblen > 0)
1430 		return doc_backup_oob(docg3, ofs, ops);
1431 
1432 	autoecc = doc_guess_autoecc(ops);
1433 	if (autoecc < 0)
1434 		return autoecc;
1435 
1436 	mutex_lock(&docg3->cascade->lock);
1437 	while (!ret && len > 0) {
1438 		memset(oob, 0, sizeof(oob));
1439 		if (ofs == docg3->oob_write_ofs)
1440 			memcpy(oob, docg3->oob_write_buf, DOC_LAYOUT_OOB_SIZE);
1441 		else if (ooblen > 0 && ops->mode == MTD_OPS_AUTO_OOB)
1442 			doc_fill_autooob(oob, oobbuf);
1443 		else if (ooblen > 0)
1444 			memcpy(oob, oobbuf, DOC_LAYOUT_OOB_SIZE);
1445 		ret = doc_write_page(docg3, ofs, buf, oob, autoecc);
1446 
1447 		ofs += DOC_LAYOUT_PAGE_SIZE;
1448 		len -= DOC_LAYOUT_PAGE_SIZE;
1449 		buf += DOC_LAYOUT_PAGE_SIZE;
1450 		if (ooblen) {
1451 			oobbuf += oobdelta;
1452 			ooblen -= oobdelta;
1453 			ops->oobretlen += oobdelta;
1454 		}
1455 		ops->retlen += DOC_LAYOUT_PAGE_SIZE;
1456 	}
1457 
1458 	doc_set_device_id(docg3, 0);
1459 	mutex_unlock(&docg3->cascade->lock);
1460 	return ret;
1461 }
1462 
sysfs_dev2docg3(struct device * dev,struct device_attribute * attr)1463 static struct docg3 *sysfs_dev2docg3(struct device *dev,
1464 				     struct device_attribute *attr)
1465 {
1466 	int floor;
1467 	struct mtd_info **docg3_floors = dev_get_drvdata(dev);
1468 
1469 	floor = attr->attr.name[1] - '0';
1470 	if (floor < 0 || floor >= DOC_MAX_NBFLOORS)
1471 		return NULL;
1472 	else
1473 		return docg3_floors[floor]->priv;
1474 }
1475 
dps0_is_key_locked(struct device * dev,struct device_attribute * attr,char * buf)1476 static ssize_t dps0_is_key_locked(struct device *dev,
1477 				  struct device_attribute *attr, char *buf)
1478 {
1479 	struct docg3 *docg3 = sysfs_dev2docg3(dev, attr);
1480 	int dps0;
1481 
1482 	mutex_lock(&docg3->cascade->lock);
1483 	doc_set_device_id(docg3, docg3->device_id);
1484 	dps0 = doc_register_readb(docg3, DOC_DPS0_STATUS);
1485 	doc_set_device_id(docg3, 0);
1486 	mutex_unlock(&docg3->cascade->lock);
1487 
1488 	return sprintf(buf, "%d\n", !(dps0 & DOC_DPS_KEY_OK));
1489 }
1490 
dps1_is_key_locked(struct device * dev,struct device_attribute * attr,char * buf)1491 static ssize_t dps1_is_key_locked(struct device *dev,
1492 				  struct device_attribute *attr, char *buf)
1493 {
1494 	struct docg3 *docg3 = sysfs_dev2docg3(dev, attr);
1495 	int dps1;
1496 
1497 	mutex_lock(&docg3->cascade->lock);
1498 	doc_set_device_id(docg3, docg3->device_id);
1499 	dps1 = doc_register_readb(docg3, DOC_DPS1_STATUS);
1500 	doc_set_device_id(docg3, 0);
1501 	mutex_unlock(&docg3->cascade->lock);
1502 
1503 	return sprintf(buf, "%d\n", !(dps1 & DOC_DPS_KEY_OK));
1504 }
1505 
dps0_insert_key(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)1506 static ssize_t dps0_insert_key(struct device *dev,
1507 			       struct device_attribute *attr,
1508 			       const char *buf, size_t count)
1509 {
1510 	struct docg3 *docg3 = sysfs_dev2docg3(dev, attr);
1511 	int i;
1512 
1513 	if (count != DOC_LAYOUT_DPS_KEY_LENGTH)
1514 		return -EINVAL;
1515 
1516 	mutex_lock(&docg3->cascade->lock);
1517 	doc_set_device_id(docg3, docg3->device_id);
1518 	for (i = 0; i < DOC_LAYOUT_DPS_KEY_LENGTH; i++)
1519 		doc_writeb(docg3, buf[i], DOC_DPS0_KEY);
1520 	doc_set_device_id(docg3, 0);
1521 	mutex_unlock(&docg3->cascade->lock);
1522 	return count;
1523 }
1524 
dps1_insert_key(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)1525 static ssize_t dps1_insert_key(struct device *dev,
1526 			       struct device_attribute *attr,
1527 			       const char *buf, size_t count)
1528 {
1529 	struct docg3 *docg3 = sysfs_dev2docg3(dev, attr);
1530 	int i;
1531 
1532 	if (count != DOC_LAYOUT_DPS_KEY_LENGTH)
1533 		return -EINVAL;
1534 
1535 	mutex_lock(&docg3->cascade->lock);
1536 	doc_set_device_id(docg3, docg3->device_id);
1537 	for (i = 0; i < DOC_LAYOUT_DPS_KEY_LENGTH; i++)
1538 		doc_writeb(docg3, buf[i], DOC_DPS1_KEY);
1539 	doc_set_device_id(docg3, 0);
1540 	mutex_unlock(&docg3->cascade->lock);
1541 	return count;
1542 }
1543 
1544 #define FLOOR_SYSFS(id) { \
1545 	__ATTR(f##id##_dps0_is_keylocked, S_IRUGO, dps0_is_key_locked, NULL), \
1546 	__ATTR(f##id##_dps1_is_keylocked, S_IRUGO, dps1_is_key_locked, NULL), \
1547 	__ATTR(f##id##_dps0_protection_key, S_IWUSR|S_IWGRP, NULL, dps0_insert_key), \
1548 	__ATTR(f##id##_dps1_protection_key, S_IWUSR|S_IWGRP, NULL, dps1_insert_key), \
1549 }
1550 
1551 static struct device_attribute doc_sys_attrs[DOC_MAX_NBFLOORS][4] = {
1552 	FLOOR_SYSFS(0), FLOOR_SYSFS(1), FLOOR_SYSFS(2), FLOOR_SYSFS(3)
1553 };
1554 
doc_register_sysfs(struct platform_device * pdev,struct docg3_cascade * cascade)1555 static int doc_register_sysfs(struct platform_device *pdev,
1556 			      struct docg3_cascade *cascade)
1557 {
1558 	struct device *dev = &pdev->dev;
1559 	int floor;
1560 	int ret;
1561 	int i;
1562 
1563 	for (floor = 0;
1564 	     floor < DOC_MAX_NBFLOORS && cascade->floors[floor];
1565 	     floor++) {
1566 		for (i = 0; i < 4; i++) {
1567 			ret = device_create_file(dev, &doc_sys_attrs[floor][i]);
1568 			if (ret)
1569 				goto remove_files;
1570 		}
1571 	}
1572 
1573 	return 0;
1574 
1575 remove_files:
1576 	do {
1577 		while (--i >= 0)
1578 			device_remove_file(dev, &doc_sys_attrs[floor][i]);
1579 		i = 4;
1580 	} while (--floor >= 0);
1581 
1582 	return ret;
1583 }
1584 
doc_unregister_sysfs(struct platform_device * pdev,struct docg3_cascade * cascade)1585 static void doc_unregister_sysfs(struct platform_device *pdev,
1586 				 struct docg3_cascade *cascade)
1587 {
1588 	struct device *dev = &pdev->dev;
1589 	int floor, i;
1590 
1591 	for (floor = 0; floor < DOC_MAX_NBFLOORS && cascade->floors[floor];
1592 	     floor++)
1593 		for (i = 0; i < 4; i++)
1594 			device_remove_file(dev, &doc_sys_attrs[floor][i]);
1595 }
1596 
1597 /*
1598  * Debug sysfs entries
1599  */
flashcontrol_show(struct seq_file * s,void * p)1600 static int flashcontrol_show(struct seq_file *s, void *p)
1601 {
1602 	struct docg3 *docg3 = s->private;
1603 
1604 	u8 fctrl;
1605 
1606 	mutex_lock(&docg3->cascade->lock);
1607 	fctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
1608 	mutex_unlock(&docg3->cascade->lock);
1609 
1610 	seq_printf(s, "FlashControl : 0x%02x (%s,CE# %s,%s,%s,flash %s)\n",
1611 		   fctrl,
1612 		   fctrl & DOC_CTRL_VIOLATION ? "protocol violation" : "-",
1613 		   fctrl & DOC_CTRL_CE ? "active" : "inactive",
1614 		   fctrl & DOC_CTRL_PROTECTION_ERROR ? "protection error" : "-",
1615 		   fctrl & DOC_CTRL_SEQUENCE_ERROR ? "sequence error" : "-",
1616 		   fctrl & DOC_CTRL_FLASHREADY ? "ready" : "not ready");
1617 
1618 	return 0;
1619 }
1620 DEFINE_SHOW_ATTRIBUTE(flashcontrol);
1621 
asic_mode_show(struct seq_file * s,void * p)1622 static int asic_mode_show(struct seq_file *s, void *p)
1623 {
1624 	struct docg3 *docg3 = s->private;
1625 
1626 	int pctrl, mode;
1627 
1628 	mutex_lock(&docg3->cascade->lock);
1629 	pctrl = doc_register_readb(docg3, DOC_ASICMODE);
1630 	mode = pctrl & 0x03;
1631 	mutex_unlock(&docg3->cascade->lock);
1632 
1633 	seq_printf(s,
1634 		   "%04x : RAM_WE=%d,RSTIN_RESET=%d,BDETCT_RESET=%d,WRITE_ENABLE=%d,POWERDOWN=%d,MODE=%d%d (",
1635 		   pctrl,
1636 		   pctrl & DOC_ASICMODE_RAM_WE ? 1 : 0,
1637 		   pctrl & DOC_ASICMODE_RSTIN_RESET ? 1 : 0,
1638 		   pctrl & DOC_ASICMODE_BDETCT_RESET ? 1 : 0,
1639 		   pctrl & DOC_ASICMODE_MDWREN ? 1 : 0,
1640 		   pctrl & DOC_ASICMODE_POWERDOWN ? 1 : 0,
1641 		   mode >> 1, mode & 0x1);
1642 
1643 	switch (mode) {
1644 	case DOC_ASICMODE_RESET:
1645 		seq_puts(s, "reset");
1646 		break;
1647 	case DOC_ASICMODE_NORMAL:
1648 		seq_puts(s, "normal");
1649 		break;
1650 	case DOC_ASICMODE_POWERDOWN:
1651 		seq_puts(s, "powerdown");
1652 		break;
1653 	}
1654 	seq_puts(s, ")\n");
1655 	return 0;
1656 }
1657 DEFINE_SHOW_ATTRIBUTE(asic_mode);
1658 
device_id_show(struct seq_file * s,void * p)1659 static int device_id_show(struct seq_file *s, void *p)
1660 {
1661 	struct docg3 *docg3 = s->private;
1662 	int id;
1663 
1664 	mutex_lock(&docg3->cascade->lock);
1665 	id = doc_register_readb(docg3, DOC_DEVICESELECT);
1666 	mutex_unlock(&docg3->cascade->lock);
1667 
1668 	seq_printf(s, "DeviceId = %d\n", id);
1669 	return 0;
1670 }
1671 DEFINE_SHOW_ATTRIBUTE(device_id);
1672 
protection_show(struct seq_file * s,void * p)1673 static int protection_show(struct seq_file *s, void *p)
1674 {
1675 	struct docg3 *docg3 = s->private;
1676 	int protect, dps0, dps0_low, dps0_high, dps1, dps1_low, dps1_high;
1677 
1678 	mutex_lock(&docg3->cascade->lock);
1679 	protect = doc_register_readb(docg3, DOC_PROTECTION);
1680 	dps0 = doc_register_readb(docg3, DOC_DPS0_STATUS);
1681 	dps0_low = doc_register_readw(docg3, DOC_DPS0_ADDRLOW);
1682 	dps0_high = doc_register_readw(docg3, DOC_DPS0_ADDRHIGH);
1683 	dps1 = doc_register_readb(docg3, DOC_DPS1_STATUS);
1684 	dps1_low = doc_register_readw(docg3, DOC_DPS1_ADDRLOW);
1685 	dps1_high = doc_register_readw(docg3, DOC_DPS1_ADDRHIGH);
1686 	mutex_unlock(&docg3->cascade->lock);
1687 
1688 	seq_printf(s, "Protection = 0x%02x (", protect);
1689 	if (protect & DOC_PROTECT_FOUNDRY_OTP_LOCK)
1690 		seq_puts(s, "FOUNDRY_OTP_LOCK,");
1691 	if (protect & DOC_PROTECT_CUSTOMER_OTP_LOCK)
1692 		seq_puts(s, "CUSTOMER_OTP_LOCK,");
1693 	if (protect & DOC_PROTECT_LOCK_INPUT)
1694 		seq_puts(s, "LOCK_INPUT,");
1695 	if (protect & DOC_PROTECT_STICKY_LOCK)
1696 		seq_puts(s, "STICKY_LOCK,");
1697 	if (protect & DOC_PROTECT_PROTECTION_ENABLED)
1698 		seq_puts(s, "PROTECTION ON,");
1699 	if (protect & DOC_PROTECT_IPL_DOWNLOAD_LOCK)
1700 		seq_puts(s, "IPL_DOWNLOAD_LOCK,");
1701 	if (protect & DOC_PROTECT_PROTECTION_ERROR)
1702 		seq_puts(s, "PROTECT_ERR,");
1703 	else
1704 		seq_puts(s, "NO_PROTECT_ERR");
1705 	seq_puts(s, ")\n");
1706 
1707 	seq_printf(s, "DPS0 = 0x%02x : Protected area [0x%x - 0x%x] : OTP=%d, READ=%d, WRITE=%d, HW_LOCK=%d, KEY_OK=%d\n",
1708 		   dps0, dps0_low, dps0_high,
1709 		   !!(dps0 & DOC_DPS_OTP_PROTECTED),
1710 		   !!(dps0 & DOC_DPS_READ_PROTECTED),
1711 		   !!(dps0 & DOC_DPS_WRITE_PROTECTED),
1712 		   !!(dps0 & DOC_DPS_HW_LOCK_ENABLED),
1713 		   !!(dps0 & DOC_DPS_KEY_OK));
1714 	seq_printf(s, "DPS1 = 0x%02x : Protected area [0x%x - 0x%x] : OTP=%d, READ=%d, WRITE=%d, HW_LOCK=%d, KEY_OK=%d\n",
1715 		   dps1, dps1_low, dps1_high,
1716 		   !!(dps1 & DOC_DPS_OTP_PROTECTED),
1717 		   !!(dps1 & DOC_DPS_READ_PROTECTED),
1718 		   !!(dps1 & DOC_DPS_WRITE_PROTECTED),
1719 		   !!(dps1 & DOC_DPS_HW_LOCK_ENABLED),
1720 		   !!(dps1 & DOC_DPS_KEY_OK));
1721 	return 0;
1722 }
1723 DEFINE_SHOW_ATTRIBUTE(protection);
1724 
doc_dbg_register(struct mtd_info * floor)1725 static void __init doc_dbg_register(struct mtd_info *floor)
1726 {
1727 	struct dentry *root = floor->dbg.dfs_dir;
1728 	struct docg3 *docg3 = floor->priv;
1729 
1730 	if (IS_ERR_OR_NULL(root)) {
1731 		if (IS_ENABLED(CONFIG_DEBUG_FS) &&
1732 		    !IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
1733 			dev_warn(floor->dev.parent,
1734 				 "CONFIG_MTD_PARTITIONED_MASTER must be enabled to expose debugfs stuff\n");
1735 		return;
1736 	}
1737 
1738 	debugfs_create_file("docg3_flashcontrol", S_IRUSR, root, docg3,
1739 			    &flashcontrol_fops);
1740 	debugfs_create_file("docg3_asic_mode", S_IRUSR, root, docg3,
1741 			    &asic_mode_fops);
1742 	debugfs_create_file("docg3_device_id", S_IRUSR, root, docg3,
1743 			    &device_id_fops);
1744 	debugfs_create_file("docg3_protection", S_IRUSR, root, docg3,
1745 			    &protection_fops);
1746 }
1747 
1748 /**
1749  * doc_set_driver_info - Fill the mtd_info structure and docg3 structure
1750  * @chip_id: The chip ID of the supported chip
1751  * @mtd: The structure to fill
1752  */
doc_set_driver_info(int chip_id,struct mtd_info * mtd)1753 static int __init doc_set_driver_info(int chip_id, struct mtd_info *mtd)
1754 {
1755 	struct docg3 *docg3 = mtd->priv;
1756 	int cfg;
1757 
1758 	cfg = doc_register_readb(docg3, DOC_CONFIGURATION);
1759 	docg3->if_cfg = (cfg & DOC_CONF_IF_CFG ? 1 : 0);
1760 	docg3->reliable = reliable_mode;
1761 
1762 	switch (chip_id) {
1763 	case DOC_CHIPID_G3:
1764 		mtd->name = devm_kasprintf(docg3->dev, GFP_KERNEL, "docg3.%d",
1765 					   docg3->device_id);
1766 		if (!mtd->name)
1767 			return -ENOMEM;
1768 		docg3->max_block = 2047;
1769 		break;
1770 	}
1771 	mtd->type = MTD_NANDFLASH;
1772 	mtd->flags = MTD_CAP_NANDFLASH;
1773 	mtd->size = (docg3->max_block + 1) * DOC_LAYOUT_BLOCK_SIZE;
1774 	if (docg3->reliable == 2)
1775 		mtd->size /= 2;
1776 	mtd->erasesize = DOC_LAYOUT_BLOCK_SIZE * DOC_LAYOUT_NBPLANES;
1777 	if (docg3->reliable == 2)
1778 		mtd->erasesize /= 2;
1779 	mtd->writebufsize = mtd->writesize = DOC_LAYOUT_PAGE_SIZE;
1780 	mtd->oobsize = DOC_LAYOUT_OOB_SIZE;
1781 	mtd->_erase = doc_erase;
1782 	mtd->_read_oob = doc_read_oob;
1783 	mtd->_write_oob = doc_write_oob;
1784 	mtd->_block_isbad = doc_block_isbad;
1785 	mtd_set_ooblayout(mtd, &nand_ooblayout_docg3_ops);
1786 	mtd->oobavail = 8;
1787 	mtd->ecc_strength = DOC_ECC_BCH_T;
1788 
1789 	return 0;
1790 }
1791 
1792 /**
1793  * doc_probe_device - Check if a device is available
1794  * @cascade: the cascade of chips this devices will belong to
1795  * @floor: the floor of the probed device
1796  * @dev: the device
1797  *
1798  * Checks whether a device at the specified IO range, and floor is available.
1799  *
1800  * Returns a mtd_info struct if there is a device, ENODEV if none found, ENOMEM
1801  * if a memory allocation failed. If floor 0 is checked, a reset of the ASIC is
1802  * launched.
1803  */
1804 static struct mtd_info * __init
doc_probe_device(struct docg3_cascade * cascade,int floor,struct device * dev)1805 doc_probe_device(struct docg3_cascade *cascade, int floor, struct device *dev)
1806 {
1807 	int ret, bbt_nbpages;
1808 	u16 chip_id, chip_id_inv;
1809 	struct docg3 *docg3;
1810 	struct mtd_info *mtd;
1811 
1812 	ret = -ENOMEM;
1813 	docg3 = kzalloc(sizeof(struct docg3), GFP_KERNEL);
1814 	if (!docg3)
1815 		goto nomem1;
1816 	mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);
1817 	if (!mtd)
1818 		goto nomem2;
1819 	mtd->priv = docg3;
1820 	mtd->dev.parent = dev;
1821 	bbt_nbpages = DIV_ROUND_UP(docg3->max_block + 1,
1822 				   8 * DOC_LAYOUT_PAGE_SIZE);
1823 	docg3->bbt = kcalloc(DOC_LAYOUT_PAGE_SIZE, bbt_nbpages, GFP_KERNEL);
1824 	if (!docg3->bbt)
1825 		goto nomem3;
1826 
1827 	docg3->dev = dev;
1828 	docg3->device_id = floor;
1829 	docg3->cascade = cascade;
1830 	doc_set_device_id(docg3, docg3->device_id);
1831 	if (!floor)
1832 		doc_set_asic_mode(docg3, DOC_ASICMODE_RESET);
1833 	doc_set_asic_mode(docg3, DOC_ASICMODE_NORMAL);
1834 
1835 	chip_id = doc_register_readw(docg3, DOC_CHIPID);
1836 	chip_id_inv = doc_register_readw(docg3, DOC_CHIPID_INV);
1837 
1838 	ret = 0;
1839 	if (chip_id != (u16)(~chip_id_inv)) {
1840 		goto nomem4;
1841 	}
1842 
1843 	switch (chip_id) {
1844 	case DOC_CHIPID_G3:
1845 		doc_info("Found a G3 DiskOnChip at addr %p, floor %d\n",
1846 			 docg3->cascade->base, floor);
1847 		break;
1848 	default:
1849 		doc_err("Chip id %04x is not a DiskOnChip G3 chip\n", chip_id);
1850 		goto nomem4;
1851 	}
1852 
1853 	ret = doc_set_driver_info(chip_id, mtd);
1854 	if (ret)
1855 		goto nomem4;
1856 
1857 	doc_hamming_ecc_init(docg3, DOC_LAYOUT_OOB_PAGEINFO_SZ);
1858 	doc_reload_bbt(docg3);
1859 	return mtd;
1860 
1861 nomem4:
1862 	kfree(docg3->bbt);
1863 nomem3:
1864 	kfree(mtd);
1865 nomem2:
1866 	kfree(docg3);
1867 nomem1:
1868 	return ret ? ERR_PTR(ret) : NULL;
1869 }
1870 
1871 /**
1872  * doc_release_device - Release a docg3 floor
1873  * @mtd: the device
1874  */
doc_release_device(struct mtd_info * mtd)1875 static void doc_release_device(struct mtd_info *mtd)
1876 {
1877 	struct docg3 *docg3 = mtd->priv;
1878 
1879 	mtd_device_unregister(mtd);
1880 	kfree(docg3->bbt);
1881 	kfree(docg3);
1882 	kfree(mtd);
1883 }
1884 
1885 /**
1886  * docg3_resume - Awakens docg3 floor
1887  * @pdev: platfrom device
1888  *
1889  * Returns 0 (always successful)
1890  */
docg3_resume(struct platform_device * pdev)1891 static int docg3_resume(struct platform_device *pdev)
1892 {
1893 	int i;
1894 	struct docg3_cascade *cascade;
1895 	struct mtd_info **docg3_floors, *mtd;
1896 	struct docg3 *docg3;
1897 
1898 	cascade = platform_get_drvdata(pdev);
1899 	docg3_floors = cascade->floors;
1900 	mtd = docg3_floors[0];
1901 	docg3 = mtd->priv;
1902 
1903 	doc_dbg("docg3_resume()\n");
1904 	for (i = 0; i < 12; i++)
1905 		doc_readb(docg3, DOC_IOSPACE_IPL);
1906 	return 0;
1907 }
1908 
1909 /**
1910  * docg3_suspend - Put in low power mode the docg3 floor
1911  * @pdev: platform device
1912  * @state: power state
1913  *
1914  * Shuts off most of docg3 circuitery to lower power consumption.
1915  *
1916  * Returns 0 if suspend succeeded, -EIO if chip refused suspend
1917  */
docg3_suspend(struct platform_device * pdev,pm_message_t state)1918 static int docg3_suspend(struct platform_device *pdev, pm_message_t state)
1919 {
1920 	int floor, i;
1921 	struct docg3_cascade *cascade;
1922 	struct mtd_info **docg3_floors, *mtd;
1923 	struct docg3 *docg3;
1924 	u8 ctrl, pwr_down;
1925 
1926 	cascade = platform_get_drvdata(pdev);
1927 	docg3_floors = cascade->floors;
1928 	for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++) {
1929 		mtd = docg3_floors[floor];
1930 		if (!mtd)
1931 			continue;
1932 		docg3 = mtd->priv;
1933 
1934 		doc_writeb(docg3, floor, DOC_DEVICESELECT);
1935 		ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
1936 		ctrl &= ~DOC_CTRL_VIOLATION & ~DOC_CTRL_CE;
1937 		doc_writeb(docg3, ctrl, DOC_FLASHCONTROL);
1938 
1939 		for (i = 0; i < 10; i++) {
1940 			usleep_range(3000, 4000);
1941 			pwr_down = doc_register_readb(docg3, DOC_POWERMODE);
1942 			if (pwr_down & DOC_POWERDOWN_READY)
1943 				break;
1944 		}
1945 		if (pwr_down & DOC_POWERDOWN_READY) {
1946 			doc_dbg("docg3_suspend(): floor %d powerdown ok\n",
1947 				floor);
1948 		} else {
1949 			doc_err("docg3_suspend(): floor %d powerdown failed\n",
1950 				floor);
1951 			return -EIO;
1952 		}
1953 	}
1954 
1955 	mtd = docg3_floors[0];
1956 	docg3 = mtd->priv;
1957 	doc_set_asic_mode(docg3, DOC_ASICMODE_POWERDOWN);
1958 	return 0;
1959 }
1960 
1961 /**
1962  * docg3_probe - Probe the IO space for a DiskOnChip G3 chip
1963  * @pdev: platform device
1964  *
1965  * Probes for a G3 chip at the specified IO space in the platform data
1966  * ressources. The floor 0 must be available.
1967  *
1968  * Returns 0 on success, -ENOMEM, -ENXIO on error
1969  */
docg3_probe(struct platform_device * pdev)1970 static int __init docg3_probe(struct platform_device *pdev)
1971 {
1972 	struct device *dev = &pdev->dev;
1973 	struct mtd_info *mtd;
1974 	struct resource *ress;
1975 	void __iomem *base;
1976 	int ret, floor;
1977 	struct docg3_cascade *cascade;
1978 
1979 	ret = -ENXIO;
1980 	ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1981 	if (!ress) {
1982 		dev_err(dev, "No I/O memory resource defined\n");
1983 		return ret;
1984 	}
1985 
1986 	ret = -ENOMEM;
1987 	base = devm_ioremap(dev, ress->start, DOC_IOSPACE_SIZE);
1988 	if (!base) {
1989 		dev_err(dev, "devm_ioremap dev failed\n");
1990 		return ret;
1991 	}
1992 
1993 	cascade = devm_kcalloc(dev, DOC_MAX_NBFLOORS, sizeof(*cascade),
1994 			       GFP_KERNEL);
1995 	if (!cascade)
1996 		return ret;
1997 	cascade->base = base;
1998 	mutex_init(&cascade->lock);
1999 	cascade->bch = bch_init(DOC_ECC_BCH_M, DOC_ECC_BCH_T,
2000 				DOC_ECC_BCH_PRIMPOLY, false);
2001 	if (!cascade->bch)
2002 		return ret;
2003 
2004 	for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++) {
2005 		mtd = doc_probe_device(cascade, floor, dev);
2006 		if (IS_ERR(mtd)) {
2007 			ret = PTR_ERR(mtd);
2008 			goto err_probe;
2009 		}
2010 		if (!mtd) {
2011 			if (floor == 0)
2012 				goto notfound;
2013 			else
2014 				continue;
2015 		}
2016 		cascade->floors[floor] = mtd;
2017 		ret = mtd_device_parse_register(mtd, part_probes, NULL, NULL,
2018 						0);
2019 		if (ret)
2020 			goto err_probe;
2021 
2022 		doc_dbg_register(cascade->floors[floor]);
2023 	}
2024 
2025 	ret = doc_register_sysfs(pdev, cascade);
2026 	if (ret)
2027 		goto err_probe;
2028 
2029 	platform_set_drvdata(pdev, cascade);
2030 	return 0;
2031 
2032 notfound:
2033 	ret = -ENODEV;
2034 	dev_info(dev, "No supported DiskOnChip found\n");
2035 err_probe:
2036 	bch_free(cascade->bch);
2037 	for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++)
2038 		if (cascade->floors[floor])
2039 			doc_release_device(cascade->floors[floor]);
2040 	return ret;
2041 }
2042 
2043 /**
2044  * docg3_release - Release the driver
2045  * @pdev: the platform device
2046  *
2047  * Returns 0
2048  */
docg3_release(struct platform_device * pdev)2049 static void docg3_release(struct platform_device *pdev)
2050 {
2051 	struct docg3_cascade *cascade = platform_get_drvdata(pdev);
2052 	struct docg3 *docg3 = cascade->floors[0]->priv;
2053 	int floor;
2054 
2055 	doc_unregister_sysfs(pdev, cascade);
2056 	for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++)
2057 		if (cascade->floors[floor])
2058 			doc_release_device(cascade->floors[floor]);
2059 
2060 	bch_free(docg3->cascade->bch);
2061 }
2062 
2063 #ifdef CONFIG_OF
2064 static const struct of_device_id docg3_dt_ids[] = {
2065 	{ .compatible = "m-systems,diskonchip-g3" },
2066 	{}
2067 };
2068 MODULE_DEVICE_TABLE(of, docg3_dt_ids);
2069 #endif
2070 
2071 static struct platform_driver g3_driver = {
2072 	.driver		= {
2073 		.name	= "docg3",
2074 		.of_match_table = of_match_ptr(docg3_dt_ids),
2075 	},
2076 	.suspend	= docg3_suspend,
2077 	.resume		= docg3_resume,
2078 	.remove_new	= docg3_release,
2079 };
2080 
2081 module_platform_driver_probe(g3_driver, docg3_probe);
2082 
2083 MODULE_LICENSE("GPL");
2084 MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
2085 MODULE_DESCRIPTION("MTD driver for DiskOnChip G3");
2086