1 
2 /*
3  * Linux driver for Disk-On-Chip Millennium
4  * (c) 1999 Machine Vision Holdings, Inc.
5  * (c) 1999, 2000 David Woodhouse <dwmw2@infradead.org>
6  *
7  * $Id: doc2001.c,v 1.38 2002/12/10 15:05:42 gleixner Exp $
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <asm/errno.h>
13 #include <asm/io.h>
14 #include <asm/uaccess.h>
15 #include <linux/miscdevice.h>
16 #include <linux/pci.h>
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 #include <linux/sched.h>
20 #include <linux/init.h>
21 #include <linux/types.h>
22 
23 #include <linux/mtd/mtd.h>
24 #include <linux/mtd/nand.h>
25 #include <linux/mtd/doc2000.h>
26 
27 /* #define ECC_DEBUG */
28 
29 /* I have no idea why some DoC chips can not use memcop_form|to_io().
30  * This may be due to the different revisions of the ASIC controller built-in or
31  * simplily a QA/Bug issue. Who knows ?? If you have trouble, please uncomment
32  * this:*/
33 #undef USE_MEMCPY
34 
35 static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
36 		    size_t *retlen, u_char *buf);
37 static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
38 		     size_t *retlen, const u_char *buf);
39 static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
40 			size_t *retlen, u_char *buf, u_char *eccbuf, int oobsel);
41 static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
42 			 size_t *retlen, const u_char *buf, u_char *eccbuf, int oobsel);
43 static int doc_read_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
44 			size_t *retlen, u_char *buf);
45 static int doc_write_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
46 			 size_t *retlen, const u_char *buf);
47 static int doc_erase (struct mtd_info *mtd, struct erase_info *instr);
48 
49 static struct mtd_info *docmillist = NULL;
50 
51 /* Perform the required delay cycles by reading from the NOP register */
DoC_Delay(unsigned long docptr,unsigned short cycles)52 static void DoC_Delay(unsigned long docptr, unsigned short cycles)
53 {
54 	volatile char dummy;
55 	int i;
56 
57 	for (i = 0; i < cycles; i++)
58 		dummy = ReadDOC(docptr, NOP);
59 }
60 
61 /* DOC_WaitReady: Wait for RDY line to be asserted by the flash chip */
_DoC_WaitReady(unsigned long docptr)62 static int _DoC_WaitReady(unsigned long docptr)
63 {
64 	unsigned short c = 0xffff;
65 
66 	DEBUG(MTD_DEBUG_LEVEL3,
67 	      "_DoC_WaitReady called for out-of-line wait\n");
68 
69 	/* Out-of-line routine to wait for chip response */
70 	while (!(ReadDOC(docptr, CDSNControl) & CDSN_CTRL_FR_B) && --c)
71 		;
72 
73 	if (c == 0)
74 		DEBUG(MTD_DEBUG_LEVEL2, "_DoC_WaitReady timed out.\n");
75 
76 	return (c == 0);
77 }
78 
DoC_WaitReady(unsigned long docptr)79 static inline int DoC_WaitReady(unsigned long docptr)
80 {
81 	/* This is inline, to optimise the common case, where it's ready instantly */
82 	int ret = 0;
83 
84 	/* 4 read form NOP register should be issued in prior to the read from CDSNControl
85 	   see Software Requirement 11.4 item 2. */
86 	DoC_Delay(docptr, 4);
87 
88 	if (!(ReadDOC(docptr, CDSNControl) & CDSN_CTRL_FR_B))
89 		/* Call the out-of-line routine to wait */
90 		ret = _DoC_WaitReady(docptr);
91 
92 	/* issue 2 read from NOP register after reading from CDSNControl register
93 	   see Software Requirement 11.4 item 2. */
94 	DoC_Delay(docptr, 2);
95 
96 	return ret;
97 }
98 
99 /* DoC_Command: Send a flash command to the flash chip through the CDSN IO register
100    with the internal pipeline. Each of 4 delay cycles (read from the NOP register) is
101    required after writing to CDSN Control register, see Software Requirement 11.4 item 3. */
102 
DoC_Command(unsigned long docptr,unsigned char command,unsigned char xtraflags)103 static inline void DoC_Command(unsigned long docptr, unsigned char command,
104 			       unsigned char xtraflags)
105 {
106 	/* Assert the CLE (Command Latch Enable) line to the flash chip */
107 	WriteDOC(xtraflags | CDSN_CTRL_CLE | CDSN_CTRL_CE, docptr, CDSNControl);
108 	DoC_Delay(docptr, 4);
109 
110 	/* Send the command */
111 	WriteDOC(command, docptr, Mil_CDSN_IO);
112 	WriteDOC(0x00, docptr, WritePipeTerm);
113 
114 	/* Lower the CLE line */
115 	WriteDOC(xtraflags | CDSN_CTRL_CE, docptr, CDSNControl);
116 	DoC_Delay(docptr, 4);
117 }
118 
119 /* DoC_Address: Set the current address for the flash chip through the CDSN IO register
120    with the internal pipeline. Each of 4 delay cycles (read from the NOP register) is
121    required after writing to CDSN Control register, see Software Requirement 11.4 item 3. */
122 
DoC_Address(unsigned long docptr,int numbytes,unsigned long ofs,unsigned char xtraflags1,unsigned char xtraflags2)123 static inline void DoC_Address(unsigned long docptr, int numbytes, unsigned long ofs,
124 			       unsigned char xtraflags1, unsigned char xtraflags2)
125 {
126 	/* Assert the ALE (Address Latch Enable) line to the flash chip */
127 	WriteDOC(xtraflags1 | CDSN_CTRL_ALE | CDSN_CTRL_CE, docptr, CDSNControl);
128 	DoC_Delay(docptr, 4);
129 
130 	/* Send the address */
131 	switch (numbytes)
132 	    {
133 	    case 1:
134 		    /* Send single byte, bits 0-7. */
135 		    WriteDOC(ofs & 0xff, docptr, Mil_CDSN_IO);
136 		    WriteDOC(0x00, docptr, WritePipeTerm);
137 		    break;
138 	    case 2:
139 		    /* Send bits 9-16 followed by 17-23 */
140 		    WriteDOC((ofs >> 9)  & 0xff, docptr, Mil_CDSN_IO);
141 		    WriteDOC((ofs >> 17) & 0xff, docptr, Mil_CDSN_IO);
142 		    WriteDOC(0x00, docptr, WritePipeTerm);
143 		break;
144 	    case 3:
145 		    /* Send 0-7, 9-16, then 17-23 */
146 		    WriteDOC(ofs & 0xff, docptr, Mil_CDSN_IO);
147 		    WriteDOC((ofs >> 9)  & 0xff, docptr, Mil_CDSN_IO);
148 		    WriteDOC((ofs >> 17) & 0xff, docptr, Mil_CDSN_IO);
149 		    WriteDOC(0x00, docptr, WritePipeTerm);
150 		break;
151 	    default:
152 		return;
153 	    }
154 
155 	/* Lower the ALE line */
156 	WriteDOC(xtraflags1 | xtraflags2 | CDSN_CTRL_CE, docptr, CDSNControl);
157 	DoC_Delay(docptr, 4);
158 }
159 
160 /* DoC_SelectChip: Select a given flash chip within the current floor */
DoC_SelectChip(unsigned long docptr,int chip)161 static int DoC_SelectChip(unsigned long docptr, int chip)
162 {
163 	/* Select the individual flash chip requested */
164 	WriteDOC(chip, docptr, CDSNDeviceSelect);
165 	DoC_Delay(docptr, 4);
166 
167 	/* Wait for it to be ready */
168 	return DoC_WaitReady(docptr);
169 }
170 
171 /* DoC_SelectFloor: Select a given floor (bank of flash chips) */
DoC_SelectFloor(unsigned long docptr,int floor)172 static int DoC_SelectFloor(unsigned long docptr, int floor)
173 {
174 	/* Select the floor (bank) of chips required */
175 	WriteDOC(floor, docptr, FloorSelect);
176 
177 	/* Wait for the chip to be ready */
178 	return DoC_WaitReady(docptr);
179 }
180 
181 /* DoC_IdentChip: Identify a given NAND chip given {floor,chip} */
DoC_IdentChip(struct DiskOnChip * doc,int floor,int chip)182 static int DoC_IdentChip(struct DiskOnChip *doc, int floor, int chip)
183 {
184 	int mfr, id, i, j;
185 	volatile char dummy;
186 
187 	/* Page in the required floor/chip
188 	   FIXME: is this supported by Millennium ?? */
189 	DoC_SelectFloor(doc->virtadr, floor);
190 	DoC_SelectChip(doc->virtadr, chip);
191 
192 	/* Reset the chip, see Software Requirement 11.4 item 1. */
193 	DoC_Command(doc->virtadr, NAND_CMD_RESET, CDSN_CTRL_WP);
194 	DoC_WaitReady(doc->virtadr);
195 
196 	/* Read the NAND chip ID: 1. Send ReadID command */
197 	DoC_Command(doc->virtadr, NAND_CMD_READID, CDSN_CTRL_WP);
198 
199 	/* Read the NAND chip ID: 2. Send address byte zero */
200 	DoC_Address(doc->virtadr, 1, 0x00, CDSN_CTRL_WP, 0x00);
201 
202 	/* Read the manufacturer and device id codes of the flash device through
203 	   CDSN IO register see Software Requirement 11.4 item 5.*/
204 	dummy = ReadDOC(doc->virtadr, ReadPipeInit);
205 	DoC_Delay(doc->virtadr, 2);
206 	mfr = ReadDOC(doc->virtadr, Mil_CDSN_IO);
207 
208 	DoC_Delay(doc->virtadr, 2);
209 	id  = ReadDOC(doc->virtadr, Mil_CDSN_IO);
210 	dummy = ReadDOC(doc->virtadr, LastDataRead);
211 
212 	/* No response - return failure */
213 	if (mfr == 0xff || mfr == 0)
214 		return 0;
215 
216 	/* FIXME: to deal with multi-flash on multi-Millennium case more carefully */
217 	for (i = 0; nand_flash_ids[i].name != NULL; i++) {
218 		if ( id == nand_flash_ids[i].id) {
219 			/* Try to identify manufacturer */
220 			for (j = 0; nand_manuf_ids[j].id != 0x0; j++) {
221 				if (nand_manuf_ids[j].id == mfr)
222 					break;
223 			}
224 			printk(KERN_INFO "Flash chip found: Manufacturer ID: %2.2X, "
225 			       "Chip ID: %2.2X (%s:%s)\n",
226 			       mfr, id, nand_manuf_ids[j].name, nand_flash_ids[i].name);
227 			doc->mfr = mfr;
228 			doc->id = id;
229 			doc->chipshift = nand_flash_ids[i].chipshift;
230 			break;
231 		}
232 	}
233 
234 	if (nand_flash_ids[i].name == NULL)
235 		return 0;
236 	else
237 		return 1;
238 }
239 
240 /* DoC_ScanChips: Find all NAND chips present in a DiskOnChip, and identify them */
DoC_ScanChips(struct DiskOnChip * this)241 static void DoC_ScanChips(struct DiskOnChip *this)
242 {
243 	int floor, chip;
244 	int numchips[MAX_FLOORS_MIL];
245 	int ret;
246 
247 	this->numchips = 0;
248 	this->mfr = 0;
249 	this->id = 0;
250 
251 	/* For each floor, find the number of valid chips it contains */
252 	for (floor = 0,ret = 1; floor < MAX_FLOORS_MIL; floor++) {
253 		numchips[floor] = 0;
254 		for (chip = 0; chip < MAX_CHIPS_MIL && ret != 0; chip++) {
255 			ret = DoC_IdentChip(this, floor, chip);
256 			if (ret) {
257 				numchips[floor]++;
258 				this->numchips++;
259 			}
260 		}
261 	}
262 	/* If there are none at all that we recognise, bail */
263 	if (!this->numchips) {
264 		printk("No flash chips recognised.\n");
265 		return;
266 	}
267 
268 	/* Allocate an array to hold the information for each chip */
269 	this->chips = kmalloc(sizeof(struct Nand) * this->numchips, GFP_KERNEL);
270 	if (!this->chips){
271 		printk("No memory for allocating chip info structures\n");
272 		return;
273 	}
274 
275 	/* Fill out the chip array with {floor, chipno} for each
276 	 * detected chip in the device. */
277 	for (floor = 0, ret = 0; floor < MAX_FLOORS_MIL; floor++) {
278 		for (chip = 0 ; chip < numchips[floor] ; chip++) {
279 			this->chips[ret].floor = floor;
280 			this->chips[ret].chip = chip;
281 			this->chips[ret].curadr = 0;
282 			this->chips[ret].curmode = 0x50;
283 			ret++;
284 		}
285 	}
286 
287 	/* Calculate and print the total size of the device */
288 	this->totlen = this->numchips * (1 << this->chipshift);
289 	printk(KERN_INFO "%d flash chips found. Total DiskOnChip size: %ld MiB\n",
290 	       this->numchips ,this->totlen >> 20);
291 }
292 
DoCMil_is_alias(struct DiskOnChip * doc1,struct DiskOnChip * doc2)293 static int DoCMil_is_alias(struct DiskOnChip *doc1, struct DiskOnChip *doc2)
294 {
295 	int tmp1, tmp2, retval;
296 
297 	if (doc1->physadr == doc2->physadr)
298 		return 1;
299 
300 	/* Use the alias resolution register which was set aside for this
301 	 * purpose. If it's value is the same on both chips, they might
302 	 * be the same chip, and we write to one and check for a change in
303 	 * the other. It's unclear if this register is usuable in the
304 	 * DoC 2000 (it's in the Millenium docs), but it seems to work. */
305 	tmp1 = ReadDOC(doc1->virtadr, AliasResolution);
306 	tmp2 = ReadDOC(doc2->virtadr, AliasResolution);
307 	if (tmp1 != tmp2)
308 		return 0;
309 
310 	WriteDOC((tmp1+1) % 0xff, doc1->virtadr, AliasResolution);
311 	tmp2 = ReadDOC(doc2->virtadr, AliasResolution);
312 	if (tmp2 == (tmp1+1) % 0xff)
313 		retval = 1;
314 	else
315 		retval = 0;
316 
317 	/* Restore register contents.  May not be necessary, but do it just to
318 	 * be safe. */
319 	WriteDOC(tmp1, doc1->virtadr, AliasResolution);
320 
321 	return retval;
322 }
323 
324 static const char im_name[] = "DoCMil_init";
325 
326 /* This routine is made available to other mtd code via
327  * inter_module_register.  It must only be accessed through
328  * inter_module_get which will bump the use count of this module.  The
329  * addresses passed back in mtd are valid as long as the use count of
330  * this module is non-zero, i.e. between inter_module_get and
331  * inter_module_put.  Keith Owens <kaos@ocs.com.au> 29 Oct 2000.
332  */
DoCMil_init(struct mtd_info * mtd)333 static void DoCMil_init(struct mtd_info *mtd)
334 {
335 	struct DiskOnChip *this = (struct DiskOnChip *)mtd->priv;
336 	struct DiskOnChip *old = NULL;
337 
338 	/* We must avoid being called twice for the same device. */
339 	if (docmillist)
340 		old = (struct DiskOnChip *)docmillist->priv;
341 
342 	while (old) {
343 		if (DoCMil_is_alias(this, old)) {
344 			printk(KERN_NOTICE "Ignoring DiskOnChip Millennium at "
345 			       "0x%lX - already configured\n", this->physadr);
346 			iounmap((void *)this->virtadr);
347 			kfree(mtd);
348 			return;
349 		}
350 		if (old->nextdoc)
351 			old = (struct DiskOnChip *)old->nextdoc->priv;
352 		else
353 			old = NULL;
354 	}
355 
356 	mtd->name = "DiskOnChip Millennium";
357 	printk(KERN_NOTICE "DiskOnChip Millennium found at address 0x%lX\n",
358 	       this->physadr);
359 
360 	mtd->type = MTD_NANDFLASH;
361 	mtd->flags = MTD_CAP_NANDFLASH;
362 	mtd->size = 0;
363 
364 	/* FIXME: erase size is not always 8kB */
365 	mtd->erasesize = 0x2000;
366 
367 	mtd->oobblock = 512;
368 	mtd->oobsize = 16;
369 	mtd->module = THIS_MODULE;
370 	mtd->erase = doc_erase;
371 	mtd->point = NULL;
372 	mtd->unpoint = NULL;
373 	mtd->read = doc_read;
374 	mtd->write = doc_write;
375 	mtd->read_ecc = doc_read_ecc;
376 	mtd->write_ecc = doc_write_ecc;
377 	mtd->read_oob = doc_read_oob;
378 	mtd->write_oob = doc_write_oob;
379 	mtd->sync = NULL;
380 
381 	this->totlen = 0;
382 	this->numchips = 0;
383 	this->curfloor = -1;
384 	this->curchip = -1;
385 
386 	/* Ident all the chips present. */
387 	DoC_ScanChips(this);
388 
389 	if (!this->totlen) {
390 		kfree(mtd);
391 		iounmap((void *)this->virtadr);
392 	} else {
393 		this->nextdoc = docmillist;
394 		docmillist = mtd;
395 		mtd->size  = this->totlen;
396 		add_mtd_device(mtd);
397 		return;
398 	}
399 }
400 
doc_read(struct mtd_info * mtd,loff_t from,size_t len,size_t * retlen,u_char * buf)401 static int doc_read (struct mtd_info *mtd, loff_t from, size_t len,
402 		     size_t *retlen, u_char *buf)
403 {
404 	/* Just a special case of doc_read_ecc */
405 	return doc_read_ecc(mtd, from, len, retlen, buf, NULL, 0);
406 }
407 
doc_read_ecc(struct mtd_info * mtd,loff_t from,size_t len,size_t * retlen,u_char * buf,u_char * eccbuf,int oobsel)408 static int doc_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
409 			 size_t *retlen, u_char *buf, u_char *eccbuf, int oobsel)
410 {
411 	int i, ret;
412 	volatile char dummy;
413 	unsigned char syndrome[6];
414 	struct DiskOnChip *this = (struct DiskOnChip *)mtd->priv;
415 	unsigned long docptr = this->virtadr;
416 	struct Nand *mychip = &this->chips[from >> (this->chipshift)];
417 
418 	/* Don't allow read past end of device */
419 	if (from >= this->totlen)
420 		return -EINVAL;
421 
422 	/* Don't allow a single read to cross a 512-byte block boundary */
423 	if (from + len > ((from | 0x1ff) + 1))
424 		len = ((from | 0x1ff) + 1) - from;
425 
426 	/* Find the chip which is to be used and select it */
427 	if (this->curfloor != mychip->floor) {
428 		DoC_SelectFloor(docptr, mychip->floor);
429 		DoC_SelectChip(docptr, mychip->chip);
430 	} else if (this->curchip != mychip->chip) {
431 		DoC_SelectChip(docptr, mychip->chip);
432 	}
433 	this->curfloor = mychip->floor;
434 	this->curchip = mychip->chip;
435 
436 	/* issue the Read0 or Read1 command depend on which half of the page
437 	   we are accessing. Polling the Flash Ready bit after issue 3 bytes
438 	   address in Sequence Read Mode, see Software Requirement 11.4 item 1.*/
439 	DoC_Command(docptr, (from >> 8) & 1, CDSN_CTRL_WP);
440 	DoC_Address(docptr, 3, from, CDSN_CTRL_WP, 0x00);
441 	DoC_WaitReady(docptr);
442 
443 	if (eccbuf) {
444 		/* init the ECC engine, see Reed-Solomon EDC/ECC 11.1 .*/
445 		WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
446 		WriteDOC (DOC_ECC_EN, docptr, ECCConf);
447 	} else {
448 		/* disable the ECC engine */
449 		WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
450 		WriteDOC (DOC_ECC_DIS, docptr, ECCConf);
451 	}
452 
453 	/* Read the data via the internal pipeline through CDSN IO register,
454 	   see Pipelined Read Operations 11.3 */
455 	dummy = ReadDOC(docptr, ReadPipeInit);
456 #ifndef USE_MEMCPY
457 	for (i = 0; i < len-1; i++) {
458 		/* N.B. you have to increase the source address in this way or the
459 		   ECC logic will not work properly */
460 		buf[i] = ReadDOC(docptr, Mil_CDSN_IO + (i & 0xff));
461 	}
462 #else
463 	memcpy_fromio(buf, docptr + DoC_Mil_CDSN_IO, len - 1);
464 #endif
465 	buf[len - 1] = ReadDOC(docptr, LastDataRead);
466 
467 	/* Let the caller know we completed it */
468 	*retlen = len;
469         ret = 0;
470 
471 	if (eccbuf) {
472 		/* Read the ECC data from Spare Data Area,
473 		   see Reed-Solomon EDC/ECC 11.1 */
474 		dummy = ReadDOC(docptr, ReadPipeInit);
475 #ifndef USE_MEMCPY
476 		for (i = 0; i < 5; i++) {
477 			/* N.B. you have to increase the source address in this way or the
478 			   ECC logic will not work properly */
479 			eccbuf[i] = ReadDOC(docptr, Mil_CDSN_IO + i);
480 		}
481 #else
482 		memcpy_fromio(eccbuf, docptr + DoC_Mil_CDSN_IO, 5);
483 #endif
484 		eccbuf[5] = ReadDOC(docptr, LastDataRead);
485 
486 		/* Flush the pipeline */
487 		dummy = ReadDOC(docptr, ECCConf);
488 		dummy = ReadDOC(docptr, ECCConf);
489 
490 		/* Check the ECC Status */
491 		if (ReadDOC(docptr, ECCConf) & 0x80) {
492                         int nb_errors;
493 			/* There was an ECC error */
494 #ifdef ECC_DEBUG
495 			printk("DiskOnChip ECC Error: Read at %lx\n", (long)from);
496 #endif
497 			/* Read the ECC syndrom through the DiskOnChip ECC logic.
498 			   These syndrome will be all ZERO when there is no error */
499 			for (i = 0; i < 6; i++) {
500 				syndrome[i] = ReadDOC(docptr, ECCSyndrome0 + i);
501 			}
502                         nb_errors = doc_decode_ecc(buf, syndrome);
503 #ifdef ECC_DEBUG
504 			printk("ECC Errors corrected: %x\n", nb_errors);
505 #endif
506                         if (nb_errors < 0) {
507 				/* We return error, but have actually done the read. Not that
508 				   this can be told to user-space, via sys_read(), but at least
509 				   MTD-aware stuff can know about it by checking *retlen */
510 				ret = -EIO;
511                         }
512 		}
513 
514 #ifdef PSYCHO_DEBUG
515 		printk("ECC DATA at %lx: %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
516 		       (long)from, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
517 		       eccbuf[4], eccbuf[5]);
518 #endif
519 
520 		/* disable the ECC engine */
521 		WriteDOC(DOC_ECC_DIS, docptr , ECCConf);
522 	}
523 
524 	return ret;
525 }
526 
doc_write(struct mtd_info * mtd,loff_t to,size_t len,size_t * retlen,const u_char * buf)527 static int doc_write (struct mtd_info *mtd, loff_t to, size_t len,
528 		      size_t *retlen, const u_char *buf)
529 {
530 	char eccbuf[6];
531 	return doc_write_ecc(mtd, to, len, retlen, buf, eccbuf, 0);
532 }
533 
doc_write_ecc(struct mtd_info * mtd,loff_t to,size_t len,size_t * retlen,const u_char * buf,u_char * eccbuf,int oobsel)534 static int doc_write_ecc (struct mtd_info *mtd, loff_t to, size_t len,
535 			  size_t *retlen, const u_char *buf, u_char *eccbuf, int oobsel)
536 {
537 	int i,ret = 0;
538 	volatile char dummy;
539 	struct DiskOnChip *this = (struct DiskOnChip *)mtd->priv;
540 	unsigned long docptr = this->virtadr;
541 	struct Nand *mychip = &this->chips[to >> (this->chipshift)];
542 
543 	/* Don't allow write past end of device */
544 	if (to >= this->totlen)
545 		return -EINVAL;
546 
547 #if 0
548 	/* Don't allow a single write to cross a 512-byte block boundary */
549 	if (to + len > ( (to | 0x1ff) + 1))
550 		len = ((to | 0x1ff) + 1) - to;
551 #else
552 	/* Don't allow writes which aren't exactly one block */
553 	if (to & 0x1ff || len != 0x200)
554 		return -EINVAL;
555 #endif
556 
557 	/* Find the chip which is to be used and select it */
558 	if (this->curfloor != mychip->floor) {
559 		DoC_SelectFloor(docptr, mychip->floor);
560 		DoC_SelectChip(docptr, mychip->chip);
561 	} else if (this->curchip != mychip->chip) {
562 		DoC_SelectChip(docptr, mychip->chip);
563 	}
564 	this->curfloor = mychip->floor;
565 	this->curchip = mychip->chip;
566 
567 	/* Reset the chip, see Software Requirement 11.4 item 1. */
568 	DoC_Command(docptr, NAND_CMD_RESET, 0x00);
569 	DoC_WaitReady(docptr);
570 	/* Set device to main plane of flash */
571 	DoC_Command(docptr, NAND_CMD_READ0, 0x00);
572 
573 	/* issue the Serial Data In command to initial the Page Program process */
574 	DoC_Command(docptr, NAND_CMD_SEQIN, 0x00);
575 	DoC_Address(docptr, 3, to, 0x00, 0x00);
576 	DoC_WaitReady(docptr);
577 
578 	if (eccbuf) {
579 		/* init the ECC engine, see Reed-Solomon EDC/ECC 11.1 .*/
580 		WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
581 		WriteDOC (DOC_ECC_EN | DOC_ECC_RW, docptr, ECCConf);
582 	} else {
583 		/* disable the ECC engine */
584 		WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
585 		WriteDOC (DOC_ECC_DIS, docptr, ECCConf);
586 	}
587 
588 	/* Write the data via the internal pipeline through CDSN IO register,
589 	   see Pipelined Write Operations 11.2 */
590 #ifndef USE_MEMCPY
591 	for (i = 0; i < len; i++) {
592 		/* N.B. you have to increase the source address in this way or the
593 		   ECC logic will not work properly */
594 		WriteDOC(buf[i], docptr, Mil_CDSN_IO + i);
595 	}
596 #else
597 	memcpy_toio(docptr + DoC_Mil_CDSN_IO, buf, len);
598 #endif
599 	WriteDOC(0x00, docptr, WritePipeTerm);
600 
601 	if (eccbuf) {
602 		/* Write ECC data to flash, the ECC info is generated by the DiskOnChip ECC logic
603 		   see Reed-Solomon EDC/ECC 11.1 */
604 		WriteDOC(0, docptr, NOP);
605 		WriteDOC(0, docptr, NOP);
606 		WriteDOC(0, docptr, NOP);
607 
608 		/* Read the ECC data through the DiskOnChip ECC logic */
609 		for (i = 0; i < 6; i++) {
610 			eccbuf[i] = ReadDOC(docptr, ECCSyndrome0 + i);
611 		}
612 
613 		/* ignore the ECC engine */
614 		WriteDOC(DOC_ECC_DIS, docptr , ECCConf);
615 
616 #ifndef USE_MEMCPY
617 		/* Write the ECC data to flash */
618 		for (i = 0; i < 6; i++) {
619 			/* N.B. you have to increase the source address in this way or the
620 			   ECC logic will not work properly */
621 			WriteDOC(eccbuf[i], docptr, Mil_CDSN_IO + i);
622 		}
623 #else
624 		memcpy_toio(docptr + DoC_Mil_CDSN_IO, eccbuf, 6);
625 #endif
626 
627 		/* write the block status BLOCK_USED (0x5555) at the end of ECC data
628 		   FIXME: this is only a hack for programming the IPL area for LinuxBIOS
629 		   and should be replace with proper codes in user space utilities */
630 		WriteDOC(0x55, docptr, Mil_CDSN_IO);
631 		WriteDOC(0x55, docptr, Mil_CDSN_IO + 1);
632 
633 		WriteDOC(0x00, docptr, WritePipeTerm);
634 
635 #ifdef PSYCHO_DEBUG
636 		printk("OOB data at %lx is %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
637 		       (long) to, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
638 		       eccbuf[4], eccbuf[5]);
639 #endif
640 	}
641 
642 	/* Commit the Page Program command and wait for ready
643 	   see Software Requirement 11.4 item 1.*/
644 	DoC_Command(docptr, NAND_CMD_PAGEPROG, 0x00);
645 	DoC_WaitReady(docptr);
646 
647 	/* Read the status of the flash device through CDSN IO register
648 	   see Software Requirement 11.4 item 5.*/
649 	DoC_Command(docptr, NAND_CMD_STATUS, CDSN_CTRL_WP);
650 	dummy = ReadDOC(docptr, ReadPipeInit);
651 	DoC_Delay(docptr, 2);
652 	if (ReadDOC(docptr, Mil_CDSN_IO) & 1) {
653 		printk("Error programming flash\n");
654 		/* Error in programming
655 		   FIXME: implement Bad Block Replacement (in nftl.c ??) */
656 		*retlen = 0;
657 		ret = -EIO;
658 	}
659 	dummy = ReadDOC(docptr, LastDataRead);
660 
661 	/* Let the caller know we completed it */
662 	*retlen = len;
663 
664 	return ret;
665 }
666 
doc_read_oob(struct mtd_info * mtd,loff_t ofs,size_t len,size_t * retlen,u_char * buf)667 static int doc_read_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
668 			size_t *retlen, u_char *buf)
669 {
670 #ifndef USE_MEMCPY
671 	int i;
672 #endif
673 	volatile char dummy;
674 	struct DiskOnChip *this = (struct DiskOnChip *)mtd->priv;
675 	unsigned long docptr = this->virtadr;
676 	struct Nand *mychip = &this->chips[ofs >> this->chipshift];
677 
678 	/* Find the chip which is to be used and select it */
679 	if (this->curfloor != mychip->floor) {
680 		DoC_SelectFloor(docptr, mychip->floor);
681 		DoC_SelectChip(docptr, mychip->chip);
682 	} else if (this->curchip != mychip->chip) {
683 		DoC_SelectChip(docptr, mychip->chip);
684 	}
685 	this->curfloor = mychip->floor;
686 	this->curchip = mychip->chip;
687 
688 	/* disable the ECC engine */
689 	WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
690 	WriteDOC (DOC_ECC_DIS, docptr, ECCConf);
691 
692 	/* issue the Read2 command to set the pointer to the Spare Data Area.
693 	   Polling the Flash Ready bit after issue 3 bytes address in
694 	   Sequence Read Mode, see Software Requirement 11.4 item 1.*/
695 	DoC_Command(docptr, NAND_CMD_READOOB, CDSN_CTRL_WP);
696 	DoC_Address(docptr, 3, ofs, CDSN_CTRL_WP, 0x00);
697 	DoC_WaitReady(docptr);
698 
699 	/* Read the data out via the internal pipeline through CDSN IO register,
700 	   see Pipelined Read Operations 11.3 */
701 	dummy = ReadDOC(docptr, ReadPipeInit);
702 #ifndef USE_MEMCPY
703 	for (i = 0; i < len-1; i++) {
704 		/* N.B. you have to increase the source address in this way or the
705 		   ECC logic will not work properly */
706 		buf[i] = ReadDOC(docptr, Mil_CDSN_IO + i);
707 	}
708 #else
709 	memcpy_fromio(buf, docptr + DoC_Mil_CDSN_IO, len - 1);
710 #endif
711 	buf[len - 1] = ReadDOC(docptr, LastDataRead);
712 
713 	*retlen = len;
714 
715 	return 0;
716 }
717 
doc_write_oob(struct mtd_info * mtd,loff_t ofs,size_t len,size_t * retlen,const u_char * buf)718 static int doc_write_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
719 			 size_t *retlen, const u_char *buf)
720 {
721 #ifndef USE_MEMCPY
722 	int i;
723 #endif
724 	volatile char dummy;
725 	int ret = 0;
726 	struct DiskOnChip *this = (struct DiskOnChip *)mtd->priv;
727 	unsigned long docptr = this->virtadr;
728 	struct Nand *mychip = &this->chips[ofs >> this->chipshift];
729 
730 	/* Find the chip which is to be used and select it */
731 	if (this->curfloor != mychip->floor) {
732 		DoC_SelectFloor(docptr, mychip->floor);
733 		DoC_SelectChip(docptr, mychip->chip);
734 	} else if (this->curchip != mychip->chip) {
735 		DoC_SelectChip(docptr, mychip->chip);
736 	}
737 	this->curfloor = mychip->floor;
738 	this->curchip = mychip->chip;
739 
740 	/* disable the ECC engine */
741 	WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
742 	WriteDOC (DOC_ECC_DIS, docptr, ECCConf);
743 
744 	/* Reset the chip, see Software Requirement 11.4 item 1. */
745 	DoC_Command(docptr, NAND_CMD_RESET, CDSN_CTRL_WP);
746 	DoC_WaitReady(docptr);
747 	/* issue the Read2 command to set the pointer to the Spare Data Area. */
748 	DoC_Command(docptr, NAND_CMD_READOOB, CDSN_CTRL_WP);
749 
750 	/* issue the Serial Data In command to initial the Page Program process */
751 	DoC_Command(docptr, NAND_CMD_SEQIN, 0x00);
752 	DoC_Address(docptr, 3, ofs, 0x00, 0x00);
753 
754 	/* Write the data via the internal pipeline through CDSN IO register,
755 	   see Pipelined Write Operations 11.2 */
756 #ifndef USE_MEMCPY
757 	for (i = 0; i < len; i++) {
758 		/* N.B. you have to increase the source address in this way or the
759 		   ECC logic will not work properly */
760 		WriteDOC(buf[i], docptr, Mil_CDSN_IO + i);
761 	}
762 #else
763 	memcpy_toio(docptr + DoC_Mil_CDSN_IO, buf, len);
764 #endif
765 	WriteDOC(0x00, docptr, WritePipeTerm);
766 
767 	/* Commit the Page Program command and wait for ready
768 	   see Software Requirement 11.4 item 1.*/
769 	DoC_Command(docptr, NAND_CMD_PAGEPROG, 0x00);
770 	DoC_WaitReady(docptr);
771 
772 	/* Read the status of the flash device through CDSN IO register
773 	   see Software Requirement 11.4 item 5.*/
774 	DoC_Command(docptr, NAND_CMD_STATUS, 0x00);
775 	dummy = ReadDOC(docptr, ReadPipeInit);
776 	DoC_Delay(docptr, 2);
777 	if (ReadDOC(docptr, Mil_CDSN_IO) & 1) {
778 		printk("Error programming oob data\n");
779 		/* FIXME: implement Bad Block Replacement (in nftl.c ??) */
780 		*retlen = 0;
781 		ret = -EIO;
782 	}
783 	dummy = ReadDOC(docptr, LastDataRead);
784 
785 	*retlen = len;
786 
787 	return ret;
788 }
789 
doc_erase(struct mtd_info * mtd,struct erase_info * instr)790 int doc_erase (struct mtd_info *mtd, struct erase_info *instr)
791 {
792 	volatile char dummy;
793 	struct DiskOnChip *this = (struct DiskOnChip *)mtd->priv;
794 	__u32 ofs = instr->addr;
795 	__u32 len = instr->len;
796 	unsigned long docptr = this->virtadr;
797 	struct Nand *mychip = &this->chips[ofs >> this->chipshift];
798 
799 	if (len != mtd->erasesize)
800 		printk(KERN_WARNING "Erase not right size (%x != %x)n",
801 		       len, mtd->erasesize);
802 
803 	/* Find the chip which is to be used and select it */
804 	if (this->curfloor != mychip->floor) {
805 		DoC_SelectFloor(docptr, mychip->floor);
806 		DoC_SelectChip(docptr, mychip->chip);
807 	} else if (this->curchip != mychip->chip) {
808 		DoC_SelectChip(docptr, mychip->chip);
809 	}
810 	this->curfloor = mychip->floor;
811 	this->curchip = mychip->chip;
812 
813 	instr->state = MTD_ERASE_PENDING;
814 
815 	/* issue the Erase Setup command */
816 	DoC_Command(docptr, NAND_CMD_ERASE1, 0x00);
817 	DoC_Address(docptr, 2, ofs, 0x00, 0x00);
818 
819 	/* Commit the Erase Start command and wait for ready
820 	   see Software Requirement 11.4 item 1.*/
821 	DoC_Command(docptr, NAND_CMD_ERASE2, 0x00);
822 	DoC_WaitReady(docptr);
823 
824 	instr->state = MTD_ERASING;
825 
826 	/* Read the status of the flash device through CDSN IO register
827 	   see Software Requirement 11.4 item 5.
828 	   FIXME: it seems that we are not wait long enough, some blocks are not
829 	   erased fully */
830 	DoC_Command(docptr, NAND_CMD_STATUS, CDSN_CTRL_WP);
831 	dummy = ReadDOC(docptr, ReadPipeInit);
832 	DoC_Delay(docptr, 2);
833 	if (ReadDOC(docptr, Mil_CDSN_IO) & 1) {
834 		printk("Error Erasing at 0x%x\n", ofs);
835 		/* There was an error
836 		   FIXME: implement Bad Block Replacement (in nftl.c ??) */
837 		instr->state = MTD_ERASE_FAILED;
838 	} else
839 		instr->state = MTD_ERASE_DONE;
840 	dummy = ReadDOC(docptr, LastDataRead);
841 
842 	if (instr->callback)
843 		instr->callback(instr);
844 
845 	return 0;
846 }
847 
848 /****************************************************************************
849  *
850  * Module stuff
851  *
852  ****************************************************************************/
853 
init_doc2001(void)854 int __init init_doc2001(void)
855 {
856 	inter_module_register(im_name, THIS_MODULE, &DoCMil_init);
857 	return 0;
858 }
859 
cleanup_doc2001(void)860 static void __exit cleanup_doc2001(void)
861 {
862 	struct mtd_info *mtd;
863 	struct DiskOnChip *this;
864 
865 	while ((mtd=docmillist)) {
866 		this = (struct DiskOnChip *)mtd->priv;
867 		docmillist = this->nextdoc;
868 
869 		del_mtd_device(mtd);
870 
871 		iounmap((void *)this->virtadr);
872 		kfree(this->chips);
873 		kfree(mtd);
874 	}
875 	inter_module_unregister(im_name);
876 }
877 
878 module_exit(cleanup_doc2001);
879 module_init(init_doc2001);
880 
881 MODULE_LICENSE("GPL");
882 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org> et al.");
883 MODULE_DESCRIPTION("Alternative driver for DiskOnChip Millennium");
884