File: /usr/src/linux/drivers/mtd/devices/doc2000.c

1     
2     /*
3      * Linux driver for Disk-On-Chip 2000 and Millennium
4      * (c) 1999 Machine Vision Holdings, Inc.
5      * (c) 1999, 2000 David Woodhouse <dwmw2@infradead.org>
6      *
7      * $Id: doc2000.c,v 1.43 2001/06/02 14:30:43 dwmw2 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/nand_ids.h>
26     #include <linux/mtd/doc2000.h>
27     
28     #define DOC_SUPPORT_2000
29     #define DOC_SUPPORT_MILLENNIUM
30     
31     #ifdef DOC_SUPPORT_2000
32     #define DoC_is_2000(doc) (doc->ChipID == DOC_ChipID_Doc2k)
33     #else
34     #define DoC_is_2000(doc) (0)
35     #endif
36     
37     #ifdef DOC_SUPPORT_MILLENNIUM
38     #define DoC_is_Millennium(doc) (doc->ChipID == DOC_ChipID_DocMil)
39     #else
40     #define DoC_is_Millennium(doc) (0)
41     #endif
42     
43     /* #define ECC_DEBUG */
44     
45     /* I have no idea why some DoC chips can not use memcpy_from|to_io().
46      * This may be due to the different revisions of the ASIC controller built-in or
47      * simplily a QA/Bug issue. Who knows ?? If you have trouble, please uncomment
48      * this:
49      #undef USE_MEMCPY
50     */
51     
52     static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
53     		    size_t *retlen, u_char *buf);
54     static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
55     		     size_t *retlen, const u_char *buf);
56     static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
57     			size_t *retlen, u_char *buf, u_char *eccbuf);
58     static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
59     			 size_t *retlen, const u_char *buf, u_char *eccbuf);
60     static int doc_read_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
61     			size_t *retlen, u_char *buf);
62     static int doc_write_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
63     			 size_t *retlen, const u_char *buf);
64     static int doc_erase (struct mtd_info *mtd, struct erase_info *instr);
65     
66     static struct mtd_info *doc2klist = NULL;
67     
68     /* Perform the required delay cycles by reading from the appropriate register */
69     static void DoC_Delay(struct DiskOnChip *doc, unsigned short cycles)
70     {
71     	volatile char dummy;
72     	int i;
73     	
74     	for (i = 0; i < cycles; i++) {
75     		if (DoC_is_Millennium(doc))
76     			dummy = ReadDOC(doc->virtadr, NOP);
77     		else
78     			dummy = ReadDOC(doc->virtadr, DOCStatus);
79     	}
80     	
81     }
82     
83     /* DOC_WaitReady: Wait for RDY line to be asserted by the flash chip */
84     static int _DoC_WaitReady(struct DiskOnChip *doc)
85     {
86     	unsigned long docptr = doc->virtadr;
87     	unsigned short c = 0xffff;
88     
89     	DEBUG(MTD_DEBUG_LEVEL3,
90     	      "_DoC_WaitReady called for out-of-line wait\n");
91     
92     	/* Out-of-line routine to wait for chip response */
93     	while (!(ReadDOC(docptr, CDSNControl) & CDSN_CTRL_FR_B) && --c)
94     		;
95     
96     	if (c == 0)
97     		DEBUG(MTD_DEBUG_LEVEL2, "_DoC_WaitReady timed out.\n");
98     
99     	return (c == 0);
100     }
101     
102     static inline int DoC_WaitReady(struct DiskOnChip *doc)
103     {
104     	unsigned long docptr = doc->virtadr;
105     	/* This is inline, to optimise the common case, where it's ready instantly */
106     	int ret = 0;
107     
108     	/* 4 read form NOP register should be issued in prior to the read from CDSNControl
109     	   see Software Requirement 11.4 item 2. */
110     	DoC_Delay(doc, 4);
111     
112     	if (!(ReadDOC(docptr, CDSNControl) & CDSN_CTRL_FR_B))
113     		/* Call the out-of-line routine to wait */
114     		ret = _DoC_WaitReady(doc);
115     
116     	/* issue 2 read from NOP register after reading from CDSNControl register
117     	   see Software Requirement 11.4 item 2. */
118     	DoC_Delay(doc, 2);
119     
120     	return ret;
121     }
122     
123     /* DoC_Command: Send a flash command to the flash chip through the CDSN Slow IO register to
124        bypass the internal pipeline. Each of 4 delay cycles (read from the NOP register) is
125        required after writing to CDSN Control register, see Software Requirement 11.4 item 3. */
126     
127     static inline int DoC_Command(struct DiskOnChip *doc, unsigned char command,
128     			      unsigned char xtraflags)
129     {
130     	unsigned long docptr = doc->virtadr;
131     
132     	if (DoC_is_2000(doc))
133     		xtraflags |= CDSN_CTRL_FLASH_IO;
134     
135     	/* Assert the CLE (Command Latch Enable) line to the flash chip */
136     	WriteDOC(xtraflags | CDSN_CTRL_CLE | CDSN_CTRL_CE, docptr, CDSNControl);
137     	DoC_Delay(doc, 4);	/* Software requirement 11.4.3 for Millennium */
138     
139     	if (DoC_is_Millennium(doc))
140     		WriteDOC(command, docptr, CDSNSlowIO);
141     
142     	/* Send the command */
143     	WriteDOC_(command, docptr, doc->ioreg);
144     
145     	/* Lower the CLE line */
146     	WriteDOC(xtraflags | CDSN_CTRL_CE, docptr, CDSNControl);
147     	DoC_Delay(doc, 4);	/* Software requirement 11.4.3 for Millennium */
148     
149     	/* Wait for the chip to respond - Software requirement 11.4.1 (extended for any command) */
150     	return DoC_WaitReady(doc);
151     }
152     
153     /* DoC_Address: Set the current address for the flash chip through the CDSN Slow IO register to
154        bypass the internal pipeline. Each of 4 delay cycles (read from the NOP register) is
155        required after writing to CDSN Control register, see Software Requirement 11.4 item 3. */
156     
157     static int DoC_Address(struct DiskOnChip *doc, int numbytes, unsigned long ofs,
158     		       unsigned char xtraflags1, unsigned char xtraflags2)
159     {
160     	unsigned long docptr;
161     	int i;
162     
163     	docptr = doc->virtadr;
164     
165     	if (DoC_is_2000(doc))
166     		xtraflags1 |= CDSN_CTRL_FLASH_IO;
167     
168     	/* Assert the ALE (Address Latch Enable) line to the flash chip */
169     	WriteDOC(xtraflags1 | CDSN_CTRL_ALE | CDSN_CTRL_CE, docptr, CDSNControl);
170     
171     	DoC_Delay(doc, 4);	/* Software requirement 11.4.3 for Millennium */
172     
173     	/* Send the address */
174     	/* Devices with 256-byte page are addressed as:
175     	   Column (bits 0-7), Page (bits 8-15, 16-23, 24-31)
176     	   * there is no device on the market with page256
177     	   and more than 24 bits.
178     	   Devices with 512-byte page are addressed as:
179     	   Column (bits 0-7), Page (bits 9-16, 17-24, 25-31)
180     	   * 25-31 is sent only if the chip support it.
181     	   * bit 8 changes the read command to be sent
182     	   (NAND_CMD_READ0 or NAND_CMD_READ1).
183     	 */
184     
185     	if (numbytes == ADDR_COLUMN || numbytes == ADDR_COLUMN_PAGE) {
186     		if (DoC_is_Millennium(doc))
187     			WriteDOC(ofs & 0xff, docptr, CDSNSlowIO);
188     		WriteDOC_(ofs & 0xff, docptr, doc->ioreg);
189     	}
190     
191     	if (doc->page256) {
192     		ofs = ofs >> 8;
193     	} else {
194     		ofs = ofs >> 9;
195     	}
196     
197     	if (numbytes == ADDR_PAGE || numbytes == ADDR_COLUMN_PAGE) {
198     		for (i = 0; i < doc->pageadrlen; i++, ofs = ofs >> 8) {
199     			if (DoC_is_Millennium(doc))
200     				WriteDOC(ofs & 0xff, docptr, CDSNSlowIO);
201     			WriteDOC_(ofs & 0xff, docptr, doc->ioreg);
202     		}
203     	}
204     
205     	DoC_Delay(doc, 2);	/* Needed for some slow flash chips. mf. */
206     	
207     	/* FIXME: The SlowIO's for millennium could be replaced by 
208     	   a single WritePipeTerm here. mf. */
209     
210     	/* Lower the ALE line */
211     	WriteDOC(xtraflags1 | xtraflags2 | CDSN_CTRL_CE, docptr,
212     		 CDSNControl);
213     
214     	DoC_Delay(doc, 4);	/* Software requirement 11.4.3 for Millennium */
215     
216     	/* Wait for the chip to respond - Software requirement 11.4.1 */
217     	return DoC_WaitReady(doc);
218     }
219     
220     /* Read a buffer from DoC, taking care of Millennium odditys */
221     static void DoC_ReadBuf(struct DiskOnChip *doc, u_char * buf, int len)
222     {
223     	int dummy;
224     	int modulus = 0xffff;
225     	unsigned long docptr;
226     	int i;
227     
228     	docptr = doc->virtadr;
229     
230     	if (len <= 0)
231     		return;
232     
233     	if (DoC_is_Millennium(doc)) {
234     		/* Read the data via the internal pipeline through CDSN IO register,
235     		   see Pipelined Read Operations 11.3 */
236     		dummy = ReadDOC(docptr, ReadPipeInit);
237     
238     		/* Millennium should use the LastDataRead register - Pipeline Reads */
239     		len--;
240     
241     		/* This is needed for correctly ECC calculation */
242     		modulus = 0xff;
243     	}
244     
245     	for (i = 0; i < len; i++)
246     		buf[i] = ReadDOC_(docptr, doc->ioreg + (i & modulus));
247     
248     	if (DoC_is_Millennium(doc)) {
249     		buf[i] = ReadDOC(docptr, LastDataRead);
250     	}
251     }
252     
253     /* Write a buffer to DoC, taking care of Millennium odditys */
254     static void DoC_WriteBuf(struct DiskOnChip *doc, const u_char * buf, int len)
255     {
256     	unsigned long docptr;
257     	int i;
258     
259     	docptr = doc->virtadr;
260     
261     	if (len <= 0)
262     		return;
263     
264     	for (i = 0; i < len; i++)
265     		WriteDOC_(buf[i], docptr, doc->ioreg + i);
266     
267     	if (DoC_is_Millennium(doc)) {
268     		WriteDOC(0x00, docptr, WritePipeTerm);
269     	}
270     }
271     
272     
273     /* DoC_SelectChip: Select a given flash chip within the current floor */
274     
275     static inline int DoC_SelectChip(struct DiskOnChip *doc, int chip)
276     {
277     	unsigned long docptr = doc->virtadr;
278     
279     	/* Software requirement 11.4.4 before writing DeviceSelect */
280     	/* Deassert the CE line to eliminate glitches on the FCE# outputs */
281     	WriteDOC(CDSN_CTRL_WP, docptr, CDSNControl);
282     	DoC_Delay(doc, 4);	/* Software requirement 11.4.3 for Millennium */
283     
284     	/* Select the individual flash chip requested */
285     	WriteDOC(chip, docptr, CDSNDeviceSelect);
286     	DoC_Delay(doc, 4);
287     
288     	/* Reassert the CE line */
289     	WriteDOC(CDSN_CTRL_CE | CDSN_CTRL_FLASH_IO | CDSN_CTRL_WP, docptr,
290     		 CDSNControl);
291     	DoC_Delay(doc, 4);	/* Software requirement 11.4.3 for Millennium */
292     
293     	/* Wait for it to be ready */
294     	return DoC_WaitReady(doc);
295     }
296     
297     /* DoC_SelectFloor: Select a given floor (bank of flash chips) */
298     
299     static inline int DoC_SelectFloor(struct DiskOnChip *doc, int floor)
300     {
301     	unsigned long docptr = doc->virtadr;
302     
303     	/* Select the floor (bank) of chips required */
304     	WriteDOC(floor, docptr, FloorSelect);
305     
306     	/* Wait for the chip to be ready */
307     	return DoC_WaitReady(doc);
308     }
309     
310     /* DoC_IdentChip: Identify a given NAND chip given {floor,chip} */
311     
312     static int DoC_IdentChip(struct DiskOnChip *doc, int floor, int chip)
313     {
314     	int mfr, id, i;
315     	volatile char dummy;
316     
317     	/* Page in the required floor/chip */
318     	DoC_SelectFloor(doc, floor);
319     	DoC_SelectChip(doc, chip);
320     
321     	/* Reset the chip */
322     	if (DoC_Command(doc, NAND_CMD_RESET, CDSN_CTRL_WP)) {
323     		DEBUG(MTD_DEBUG_LEVEL2,
324     		      "DoC_Command (reset) for %d,%d returned true\n",
325     		      floor, chip);
326     		return 0;
327     	}
328     
329     
330     	/* Read the NAND chip ID: 1. Send ReadID command */
331     	if (DoC_Command(doc, NAND_CMD_READID, CDSN_CTRL_WP)) {
332     		DEBUG(MTD_DEBUG_LEVEL2,
333     		      "DoC_Command (ReadID) for %d,%d returned true\n",
334     		      floor, chip);
335     		return 0;
336     	}
337     
338     	/* Read the NAND chip ID: 2. Send address byte zero */
339     	DoC_Address(doc, ADDR_COLUMN, 0, CDSN_CTRL_WP, 0);
340     
341     	/* Read the manufacturer and device id codes from the device */
342     
343     	/* CDSN Slow IO register see Software Requirement 11.4 item 5. */
344     	dummy = ReadDOC(doc->virtadr, CDSNSlowIO);
345     	DoC_Delay(doc, 2);
346     	mfr = ReadDOC_(doc->virtadr, doc->ioreg);
347     
348     	/* CDSN Slow IO register see Software Requirement 11.4 item 5. */
349     	dummy = ReadDOC(doc->virtadr, CDSNSlowIO);
350     	DoC_Delay(doc, 2);
351     	id = ReadDOC_(doc->virtadr, doc->ioreg);
352     
353     	/* No response - return failure */
354     	if (mfr == 0xff || mfr == 0)
355     		return 0;
356     
357     	/* Check it's the same as the first chip we identified. 
358     	 * M-Systems say that any given DiskOnChip device should only
359     	 * contain _one_ type of flash part, although that's not a 
360     	 * hardware restriction. */
361     	if (doc->mfr) {
362     		if (doc->mfr == mfr && doc->id == id)
363     			return 1;	/* This is another the same the first */
364     		else
365     			printk(KERN_WARNING
366     			       "Flash chip at floor %d, chip %d is different:\n",
367     			       floor, chip);
368     	}
369     
370     	/* Print and store the manufacturer and ID codes. */
371     	for (i = 0; nand_flash_ids[i].name != NULL; i++) {
372     		if (mfr == nand_flash_ids[i].manufacture_id &&
373     		    id == nand_flash_ids[i].model_id) {
374     			printk(KERN_INFO
375     			       "Flash chip found: Manufacturer ID: %2.2X, "
376     			       "Chip ID: %2.2X (%s)\n", mfr, id,
377     			       nand_flash_ids[i].name);
378     			if (!doc->mfr) {
379     				doc->mfr = mfr;
380     				doc->id = id;
381     				doc->chipshift =
382     				    nand_flash_ids[i].chipshift;
383     				doc->page256 = nand_flash_ids[i].page256;
384     				doc->pageadrlen =
385     				    nand_flash_ids[i].pageadrlen;
386     				doc->erasesize =
387     				    nand_flash_ids[i].erasesize;
388     				return 1;
389     			}
390     			return 0;
391     		}
392     	}
393     
394     
395     	/* We haven't fully identified the chip. Print as much as we know. */
396     	printk(KERN_WARNING "Unknown flash chip found: %2.2X %2.2X\n",
397     	       id, mfr);
398     
399     	printk(KERN_WARNING "Please report to dwmw2@infradead.org\n");
400     	return 0;
401     }
402     
403     /* DoC_ScanChips: Find all NAND chips present in a DiskOnChip, and identify them */
404     
405     static void DoC_ScanChips(struct DiskOnChip *this)
406     {
407     	int floor, chip;
408     	int numchips[MAX_FLOORS];
409     	int maxchips = MAX_CHIPS;
410     	int ret = 1;
411     
412     	this->numchips = 0;
413     	this->mfr = 0;
414     	this->id = 0;
415     
416     	if (DoC_is_Millennium(this))
417     		maxchips = MAX_CHIPS_MIL;
418     
419     	/* For each floor, find the number of valid chips it contains */
420     	for (floor = 0; floor < MAX_FLOORS; floor++) {
421     		ret = 1;
422     		numchips[floor] = 0;
423     		for (chip = 0; chip < maxchips && ret != 0; chip++) {
424     
425     			ret = DoC_IdentChip(this, floor, chip);
426     			if (ret) {
427     				numchips[floor]++;
428     				this->numchips++;
429     			}
430     		}
431     	}
432     
433     	/* If there are none at all that we recognise, bail */
434     	if (!this->numchips) {
435     		printk("No flash chips recognised.\n");
436     		return;
437     	}
438     
439     	/* Allocate an array to hold the information for each chip */
440     	this->chips = kmalloc(sizeof(struct Nand) * this->numchips, GFP_KERNEL);
441     	if (!this->chips) {
442     		printk("No memory for allocating chip info structures\n");
443     		return;
444     	}
445     
446     	ret = 0;
447     
448     	/* Fill out the chip array with {floor, chipno} for each 
449     	 * detected chip in the device. */
450     	for (floor = 0; floor < MAX_FLOORS; floor++) {
451     		for (chip = 0; chip < numchips[floor]; chip++) {
452     			this->chips[ret].floor = floor;
453     			this->chips[ret].chip = chip;
454     			this->chips[ret].curadr = 0;
455     			this->chips[ret].curmode = 0x50;
456     			ret++;
457     		}
458     	}
459     
460     	/* Calculate and print the total size of the device */
461     	this->totlen = this->numchips * (1 << this->chipshift);
462     
463     	printk(KERN_INFO "%d flash chips found. Total DiskOnChip size: %ld MiB\n",
464     	       this->numchips, this->totlen >> 20);
465     }
466     
467     static int DoC2k_is_alias(struct DiskOnChip *doc1, struct DiskOnChip *doc2)
468     {
469     	int tmp1, tmp2, retval;
470     	if (doc1->physadr == doc2->physadr)
471     		return 1;
472     
473     	/* Use the alias resolution register which was set aside for this
474     	 * purpose. If it's value is the same on both chips, they might
475     	 * be the same chip, and we write to one and check for a change in
476     	 * the other. It's unclear if this register is usuable in the
477     	 * DoC 2000 (it's in the Millennium docs), but it seems to work. */
478     	tmp1 = ReadDOC(doc1->virtadr, AliasResolution);
479     	tmp2 = ReadDOC(doc2->virtadr, AliasResolution);
480     	if (tmp1 != tmp2)
481     		return 0;
482     
483     	WriteDOC((tmp1 + 1) % 0xff, doc1->virtadr, AliasResolution);
484     	tmp2 = ReadDOC(doc2->virtadr, AliasResolution);
485     	if (tmp2 == (tmp1 + 1) % 0xff)
486     		retval = 1;
487     	else
488     		retval = 0;
489     
490     	/* Restore register contents.  May not be necessary, but do it just to
491     	 * be safe. */
492     	WriteDOC(tmp1, doc1->virtadr, AliasResolution);
493     
494     	return retval;
495     }
496     
497     static const char im_name[] = "DoC2k_init";
498     
499     /* This routine is made available to other mtd code via
500      * inter_module_register.  It must only be accessed through
501      * inter_module_get which will bump the use count of this module.  The
502      * addresses passed back in mtd are valid as long as the use count of
503      * this module is non-zero, i.e. between inter_module_get and
504      * inter_module_put.  Keith Owens <kaos@ocs.com.au> 29 Oct 2000.
505      */
506     static void DoC2k_init(struct mtd_info *mtd)
507     {
508     	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
509     	struct DiskOnChip *old = NULL;
510     
511     	/* We must avoid being called twice for the same device. */
512     
513     	if (doc2klist)
514     		old = (struct DiskOnChip *) doc2klist->priv;
515     
516     	while (old) {
517     		if (DoC2k_is_alias(old, this)) {
518     			printk(KERN_NOTICE
519     			       "Ignoring DiskOnChip 2000 at 0x%lX - already configured\n",
520     			       this->physadr);
521     			iounmap((void *) this->virtadr);
522     			kfree(mtd);
523     			return;
524     		}
525     		if (old->nextdoc)
526     			old = (struct DiskOnChip *) old->nextdoc->priv;
527     		else
528     			old = NULL;
529     	}
530     
531     
532     	switch (this->ChipID) {
533     	case DOC_ChipID_Doc2k:
534     		mtd->name = "DiskOnChip 2000";
535     		this->ioreg = DoC_2k_CDSN_IO;
536     		break;
537     	case DOC_ChipID_DocMil:
538     		mtd->name = "DiskOnChip Millennium";
539     		this->ioreg = DoC_Mil_CDSN_IO;
540     		break;
541     	}
542     
543     	printk(KERN_NOTICE "%s found at address 0x%lX\n", mtd->name,
544     	       this->physadr);
545     
546     	mtd->type = MTD_NANDFLASH;
547     	mtd->flags = MTD_CAP_NANDFLASH;
548     	mtd->size = 0;
549     	mtd->erasesize = 0;
550     	mtd->oobblock = 512;
551     	mtd->oobsize = 16;
552     	mtd->module = THIS_MODULE;
553     	mtd->erase = doc_erase;
554     	mtd->point = NULL;
555     	mtd->unpoint = NULL;
556     	mtd->read = doc_read;
557     	mtd->write = doc_write;
558     	mtd->read_ecc = doc_read_ecc;
559     	mtd->write_ecc = doc_write_ecc;
560     	mtd->read_oob = doc_read_oob;
561     	mtd->write_oob = doc_write_oob;
562     	mtd->sync = NULL;
563     
564     	this->totlen = 0;
565     	this->numchips = 0;
566     
567     	this->curfloor = -1;
568     	this->curchip = -1;
569     
570     	/* Ident all the chips present. */
571     	DoC_ScanChips(this);
572     
573     	if (!this->totlen) {
574     		kfree(mtd);
575     		iounmap((void *) this->virtadr);
576     	} else {
577     		this->nextdoc = doc2klist;
578     		doc2klist = mtd;
579     		mtd->size = this->totlen;
580     		mtd->erasesize = this->erasesize;
581     		add_mtd_device(mtd);
582     		return;
583     	}
584     }
585     
586     static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
587     		    size_t * retlen, u_char * buf)
588     {
589     	/* Just a special case of doc_read_ecc */
590     	return doc_read_ecc(mtd, from, len, retlen, buf, NULL);
591     }
592     
593     static int doc_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
594     			size_t * retlen, u_char * buf, u_char * eccbuf)
595     {
596     	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
597     	unsigned long docptr;
598     	struct Nand *mychip;
599     	unsigned char syndrome[6];
600     	volatile char dummy;
601     	int i, len256 = 0, ret=0;
602     
603     	docptr = this->virtadr;
604     
605     	/* Don't allow read past end of device */
606     	if (from >= this->totlen)
607     		return -EINVAL;
608     
609     	/* Don't allow a single read to cross a 512-byte block boundary */
610     	if (from + len > ((from | 0x1ff) + 1))
611     		len = ((from | 0x1ff) + 1) - from;
612     
613     	/* The ECC will not be calculated correctly if less than 512 is read */
614     	if (len != 0x200 && eccbuf)
615     		printk(KERN_WARNING
616     		       "ECC needs a full sector read (adr: %lx size %lx)\n",
617     		       (long) from, (long) len);
618     
619     	/* printk("DoC_Read (adr: %lx size %lx)\n", (long) from, (long) len); */
620     
621     
622     	/* Find the chip which is to be used and select it */
623     	mychip = &this->chips[from >> (this->chipshift)];
624     
625     	if (this->curfloor != mychip->floor) {
626     		DoC_SelectFloor(this, mychip->floor);
627     		DoC_SelectChip(this, mychip->chip);
628     	} else if (this->curchip != mychip->chip) {
629     		DoC_SelectChip(this, mychip->chip);
630     	}
631     
632     	this->curfloor = mychip->floor;
633     	this->curchip = mychip->chip;
634     
635     	DoC_Command(this,
636     		    (!this->page256
637     		     && (from & 0x100)) ? NAND_CMD_READ1 : NAND_CMD_READ0,
638     		    CDSN_CTRL_WP);
639     	DoC_Address(this, ADDR_COLUMN_PAGE, from, CDSN_CTRL_WP,
640     		    CDSN_CTRL_ECC_IO);
641     
642     	if (eccbuf) {
643     		/* Prime the ECC engine */
644     		WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
645     		WriteDOC(DOC_ECC_EN, docptr, ECCConf);
646     	} else {
647     		/* disable the ECC engine */
648     		WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
649     		WriteDOC(DOC_ECC_DIS, docptr, ECCConf);
650     	}
651     
652     	/* treat crossing 256-byte sector for 2M x 8bits devices */
653     	if (this->page256 && from + len > (from | 0xff) + 1) {
654     		len256 = (from | 0xff) + 1 - from;
655     		DoC_ReadBuf(this, buf, len256);
656     
657     		DoC_Command(this, NAND_CMD_READ0, CDSN_CTRL_WP);
658     		DoC_Address(this, ADDR_COLUMN_PAGE, from + len256,
659     			    CDSN_CTRL_WP, CDSN_CTRL_ECC_IO);
660     	}
661     
662     	DoC_ReadBuf(this, &buf[len256], len - len256);
663     
664     	/* Let the caller know we completed it */
665     	*retlen = len;
666     
667     	if (eccbuf) {
668     		/* Read the ECC data through the DiskOnChip ECC logic */
669     		/* Note: this will work even with 2M x 8bit devices as   */
670     		/*       they have 8 bytes of OOB per 256 page. mf.      */
671     		DoC_ReadBuf(this, eccbuf, 6);
672     
673     		/* Flush the pipeline */
674     		if (DoC_is_Millennium(this)) {
675     			dummy = ReadDOC(docptr, ECCConf);
676     			dummy = ReadDOC(docptr, ECCConf);
677     			i = ReadDOC(docptr, ECCConf);
678     		} else {
679     			dummy = ReadDOC(docptr, 2k_ECCStatus);
680     			dummy = ReadDOC(docptr, 2k_ECCStatus);
681     			i = ReadDOC(docptr, 2k_ECCStatus);
682     		}
683     
684     		/* Check the ECC Status */
685     		if (i & 0x80) {
686     			int nb_errors;
687     			/* There was an ECC error */
688     #ifdef ECC_DEBUG
689     			printk("DiskOnChip ECC Error: Read at %lx\n", (long)from);
690     #endif
691     			/* Read the ECC syndrom through the DiskOnChip ECC logic.
692     			   These syndrome will be all ZERO when there is no error */
693     			for (i = 0; i < 6; i++) {
694     				syndrome[i] =
695     				    ReadDOC(docptr, ECCSyndrome0 + i);
696     			}
697                             nb_errors = doc_decode_ecc(buf, syndrome);
698     
699     #ifdef ECC_DEBUG
700     			printk("Errors corrected: %x\n", nb_errors);
701     #endif
702                             if (nb_errors < 0) {
703     				/* We return error, but have actually done the read. Not that
704     				   this can be told to user-space, via sys_read(), but at least
705     				   MTD-aware stuff can know about it by checking *retlen */
706     				ret = -EIO;
707                             }
708     		}
709     
710     #ifdef PSYCHO_DEBUG
711     		printk("ECC DATA at %lxB: %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
712     			     (long)from, eccbuf[0], eccbuf[1], eccbuf[2],
713     			     eccbuf[3], eccbuf[4], eccbuf[5]);
714     #endif
715     		
716     		/* disable the ECC engine */
717     		WriteDOC(DOC_ECC_DIS, docptr , ECCConf);
718     	}
719     
720     	/* according to 11.4.1, we need to wait for the busy line 
721              * drop if we read to the end of the page.  */
722     	if(0 == ((from + *retlen) & 0x1ff))
723     	{
724     	    DoC_WaitReady(this);
725     	}
726     
727     	return ret;
728     }
729     
730     static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
731     		     size_t * retlen, const u_char * buf)
732     {
733     	char eccbuf[6];
734     	return doc_write_ecc(mtd, to, len, retlen, buf, eccbuf);
735     }
736     
737     static int doc_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
738     			 size_t * retlen, const u_char * buf,
739     			 u_char * eccbuf)
740     {
741     	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
742     	int di; /* Yes, DI is a hangover from when I was disassembling the binary driver */
743     	unsigned long docptr;
744     	volatile char dummy;
745     	int len256 = 0;
746     	struct Nand *mychip;
747     
748     	docptr = this->virtadr;
749     
750     	/* Don't allow write past end of device */
751     	if (to >= this->totlen)
752     		return -EINVAL;
753     
754     	/* Don't allow a single write to cross a 512-byte block boundary */
755     	if (to + len > ((to | 0x1ff) + 1))
756     		len = ((to | 0x1ff) + 1) - to;
757     
758     	/* The ECC will not be calculated correctly if less than 512 is written */
759     	if (len != 0x200 && eccbuf)
760     		printk(KERN_WARNING
761     		       "ECC needs a full sector write (adr: %lx size %lx)\n",
762     		       (long) to, (long) len);
763     
764     	/* printk("DoC_Write (adr: %lx size %lx)\n", (long) to, (long) len); */
765     
766     	/* Find the chip which is to be used and select it */
767     	mychip = &this->chips[to >> (this->chipshift)];
768     
769     	if (this->curfloor != mychip->floor) {
770     		DoC_SelectFloor(this, mychip->floor);
771     		DoC_SelectChip(this, mychip->chip);
772     	} else if (this->curchip != mychip->chip) {
773     		DoC_SelectChip(this, mychip->chip);
774     	}
775     
776     	this->curfloor = mychip->floor;
777     	this->curchip = mychip->chip;
778     
779     	/* Set device to main plane of flash */
780     	DoC_Command(this, NAND_CMD_RESET, CDSN_CTRL_WP);
781     	DoC_Command(this,
782     		    (!this->page256
783     		     && (to & 0x100)) ? NAND_CMD_READ1 : NAND_CMD_READ0,
784     		    CDSN_CTRL_WP);
785     
786     	DoC_Command(this, NAND_CMD_SEQIN, 0);
787     	DoC_Address(this, ADDR_COLUMN_PAGE, to, 0, CDSN_CTRL_ECC_IO);
788     
789     	if (eccbuf) {
790     		/* Prime the ECC engine */
791     		WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
792     		WriteDOC(DOC_ECC_EN | DOC_ECC_RW, docptr, ECCConf);
793     	} else {
794     		/* disable the ECC engine */
795     		WriteDOC(DOC_ECC_RESET, docptr, ECCConf);
796     		WriteDOC(DOC_ECC_DIS, docptr, ECCConf);
797     	}
798     
799     	/* treat crossing 256-byte sector for 2M x 8bits devices */
800     	if (this->page256 && to + len > (to | 0xff) + 1) {
801     		len256 = (to | 0xff) + 1 - to;
802     		DoC_WriteBuf(this, buf, len256);
803     
804     		DoC_Command(this, NAND_CMD_PAGEPROG, 0);
805     
806     		DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);
807     		/* There's an implicit DoC_WaitReady() in DoC_Command */
808     
809     		dummy = ReadDOC(docptr, CDSNSlowIO);
810     		DoC_Delay(this, 2);
811     
812     		if (ReadDOC_(docptr, this->ioreg) & 1) {
813     			printk("Error programming flash\n");
814     			/* Error in programming */
815     			*retlen = 0;
816     			return -EIO;
817     		}
818     
819     		DoC_Command(this, NAND_CMD_SEQIN, 0);
820     		DoC_Address(this, ADDR_COLUMN_PAGE, to + len256, 0,
821     			    CDSN_CTRL_ECC_IO);
822     	}
823     
824     	DoC_WriteBuf(this, &buf[len256], len - len256);
825     
826     	if (eccbuf) {
827     		WriteDOC(CDSN_CTRL_ECC_IO | CDSN_CTRL_CE, docptr,
828     			 CDSNControl);
829     
830     		if (DoC_is_Millennium(this)) {
831     			WriteDOC(0, docptr, NOP);
832     			WriteDOC(0, docptr, NOP);
833     			WriteDOC(0, docptr, NOP);
834     		} else {
835     			WriteDOC_(0, docptr, this->ioreg);
836     			WriteDOC_(0, docptr, this->ioreg);
837     			WriteDOC_(0, docptr, this->ioreg);
838     		}
839     
840     		/* Read the ECC data through the DiskOnChip ECC logic */
841     		for (di = 0; di < 6; di++) {
842     			eccbuf[di] = ReadDOC(docptr, ECCSyndrome0 + di);
843     		}
844     
845     		/* Reset the ECC engine */
846     		WriteDOC(DOC_ECC_DIS, docptr, ECCConf);
847     
848     #ifdef PSYCHO_DEBUG
849     		printk
850     		    ("OOB data at %lx is %2.2X %2.2X %2.2X %2.2X %2.2X %2.2X\n",
851     		     (long) to, eccbuf[0], eccbuf[1], eccbuf[2], eccbuf[3],
852     		     eccbuf[4], eccbuf[5]);
853     #endif
854     	}
855     
856     	DoC_Command(this, NAND_CMD_PAGEPROG, 0);
857     
858     	DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);
859     	/* There's an implicit DoC_WaitReady() in DoC_Command */
860     
861     	dummy = ReadDOC(docptr, CDSNSlowIO);
862     	DoC_Delay(this, 2);
863     
864     	if (ReadDOC_(docptr, this->ioreg) & 1) {
865     		printk("Error programming flash\n");
866     		/* Error in programming */
867     		*retlen = 0;
868     		return -EIO;
869     	}
870     
871     	/* Let the caller know we completed it */
872     	*retlen = len;
873     		
874     	if (eccbuf) {
875     		unsigned char x[8];
876     		size_t dummy;
877     
878     		/* Write the ECC data to flash */
879     		for (di=0; di<6; di++)
880     			x[di] = eccbuf[di];
881     		
882     		x[6]=0x55;
883     		x[7]=0x55;
884     		
885     		return doc_write_oob(mtd, to, 8, &dummy, x);
886     	}
887     
888     	return 0;
889     }
890     
891     static int doc_read_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
892     			size_t * retlen, u_char * buf)
893     {
894     	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
895     	int len256 = 0;
896     	unsigned long docptr;
897     	struct Nand *mychip;
898     
899     	docptr = this->virtadr;
900     
901     	mychip = &this->chips[ofs >> this->chipshift];
902     
903     	if (this->curfloor != mychip->floor) {
904     		DoC_SelectFloor(this, mychip->floor);
905     		DoC_SelectChip(this, mychip->chip);
906     	} else if (this->curchip != mychip->chip) {
907     		DoC_SelectChip(this, mychip->chip);
908     	}
909     	this->curfloor = mychip->floor;
910     	this->curchip = mychip->chip;
911     
912     	/* update address for 2M x 8bit devices. OOB starts on the second */
913     	/* page to maintain compatibility with doc_read_ecc. */
914     	if (this->page256) {
915     		if (!(ofs & 0x8))
916     			ofs += 0x100;
917     		else
918     			ofs -= 0x8;
919     	}
920     
921     	DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);
922     	DoC_Address(this, ADDR_COLUMN_PAGE, ofs, CDSN_CTRL_WP, 0);
923     
924     	/* treat crossing 8-byte OOB data for 2M x 8bit devices */
925     	/* Note: datasheet says it should automaticaly wrap to the */
926     	/*       next OOB block, but it didn't work here. mf.      */
927     	if (this->page256 && ofs + len > (ofs | 0x7) + 1) {
928     		len256 = (ofs | 0x7) + 1 - ofs;
929     		DoC_ReadBuf(this, buf, len256);
930     
931     		DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);
932     		DoC_Address(this, ADDR_COLUMN_PAGE, ofs & (~0x1ff),
933     			    CDSN_CTRL_WP, 0);
934     	}
935     
936     	DoC_ReadBuf(this, &buf[len256], len - len256);
937     
938     	*retlen = len;
939     	/* Reading the full OOB data drops us off of the end of the page,
940              * causing the flash device to go into busy mode, so we need
941              * to wait until ready 11.4.1 and Toshiba TC58256FT docs */
942     	return DoC_WaitReady(this);
943     
944     }
945     
946     static int doc_write_oob(struct mtd_info *mtd, loff_t ofs, size_t len,
947     			 size_t * retlen, const u_char * buf)
948     {
949     	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
950     	int len256 = 0;
951     	unsigned long docptr = this->virtadr;
952     	struct Nand *mychip = &this->chips[ofs >> this->chipshift];
953     	int dummy;
954     
955     	//      printk("doc_write_oob(%lx, %d): %2.2X %2.2X %2.2X %2.2X ... %2.2X %2.2X .. %2.2X %2.2X\n",(long)ofs, len,
956     	//   buf[0], buf[1], buf[2], buf[3], buf[8], buf[9], buf[14],buf[15]);
957     
958     	/* Find the chip which is to be used and select it */
959     	if (this->curfloor != mychip->floor) {
960     		DoC_SelectFloor(this, mychip->floor);
961     		DoC_SelectChip(this, mychip->chip);
962     	} else if (this->curchip != mychip->chip) {
963     		DoC_SelectChip(this, mychip->chip);
964     	}
965     	this->curfloor = mychip->floor;
966     	this->curchip = mychip->chip;
967     
968     	/* disable the ECC engine */
969     	WriteDOC (DOC_ECC_RESET, docptr, ECCConf);
970     	WriteDOC (DOC_ECC_DIS, docptr, ECCConf);
971     
972     	/* Reset the chip, see Software Requirement 11.4 item 1. */
973     	DoC_Command(this, NAND_CMD_RESET, CDSN_CTRL_WP);
974     
975     	/* issue the Read2 command to set the pointer to the Spare Data Area. */
976     	DoC_Command(this, NAND_CMD_READOOB, CDSN_CTRL_WP);
977     
978     	/* update address for 2M x 8bit devices. OOB starts on the second */
979     	/* page to maintain compatibility with doc_read_ecc. */
980     	if (this->page256) {
981     		if (!(ofs & 0x8))
982     			ofs += 0x100;
983     		else
984     			ofs -= 0x8;
985     	}
986     
987     	/* issue the Serial Data In command to initial the Page Program process */
988     	DoC_Command(this, NAND_CMD_SEQIN, 0);
989     	DoC_Address(this, ADDR_COLUMN_PAGE, ofs, 0, 0);
990     
991     	/* treat crossing 8-byte OOB data for 2M x 8bit devices */
992     	/* Note: datasheet says it should automaticaly wrap to the */
993     	/*       next OOB block, but it didn't work here. mf.      */
994     	if (this->page256 && ofs + len > (ofs | 0x7) + 1) {
995     		len256 = (ofs | 0x7) + 1 - ofs;
996     		DoC_WriteBuf(this, buf, len256);
997     
998     		DoC_Command(this, NAND_CMD_PAGEPROG, 0);
999     		DoC_Command(this, NAND_CMD_STATUS, 0);
1000     		/* DoC_WaitReady() is implicit in DoC_Command */
1001     
1002     		dummy = ReadDOC(docptr, CDSNSlowIO);
1003     		DoC_Delay(this, 2);
1004     
1005     		if (ReadDOC_(docptr, this->ioreg) & 1) {
1006     			printk("Error programming oob data\n");
1007     			/* There was an error */
1008     			*retlen = 0;
1009     			return -EIO;
1010     		}
1011     		DoC_Command(this, NAND_CMD_SEQIN, 0);
1012     		DoC_Address(this, ADDR_COLUMN_PAGE, ofs & (~0x1ff), 0, 0);
1013     	}
1014     
1015     	DoC_WriteBuf(this, &buf[len256], len - len256);
1016     
1017     	DoC_Command(this, NAND_CMD_PAGEPROG, 0);
1018     	DoC_Command(this, NAND_CMD_STATUS, 0);
1019     	/* DoC_WaitReady() is implicit in DoC_Command */
1020     
1021     	dummy = ReadDOC(docptr, CDSNSlowIO);
1022     	DoC_Delay(this, 2);
1023     
1024     	if (ReadDOC_(docptr, this->ioreg) & 1) {
1025     		printk("Error programming oob data\n");
1026     		/* There was an error */
1027     		*retlen = 0;
1028     		return -EIO;
1029     	}
1030     
1031     	*retlen = len;
1032     	return 0;
1033     
1034     }
1035     
1036     int doc_erase(struct mtd_info *mtd, struct erase_info *instr)
1037     {
1038     	struct DiskOnChip *this = (struct DiskOnChip *) mtd->priv;
1039     	__u32 ofs = instr->addr;
1040     	__u32 len = instr->len;
1041     	unsigned long docptr;
1042     	struct Nand *mychip;
1043     
1044     	if (len != mtd->erasesize)
1045     		printk(KERN_WARNING "Erase not right size (%x != %x)n",
1046     		       len, mtd->erasesize);
1047     
1048     	docptr = this->virtadr;
1049     
1050     	mychip = &this->chips[ofs >> this->chipshift];
1051     
1052     	if (this->curfloor != mychip->floor) {
1053     		DoC_SelectFloor(this, mychip->floor);
1054     		DoC_SelectChip(this, mychip->chip);
1055     	} else if (this->curchip != mychip->chip) {
1056     		DoC_SelectChip(this, mychip->chip);
1057     	}
1058     	this->curfloor = mychip->floor;
1059     	this->curchip = mychip->chip;
1060     
1061     	instr->state = MTD_ERASE_PENDING;
1062     
1063     	DoC_Command(this, NAND_CMD_ERASE1, 0);
1064     	DoC_Address(this, ADDR_PAGE, ofs, 0, 0);
1065     	DoC_Command(this, NAND_CMD_ERASE2, 0);
1066     
1067     	instr->state = MTD_ERASING;
1068     
1069     	DoC_Command(this, NAND_CMD_STATUS, CDSN_CTRL_WP);
1070     
1071     	if (ReadDOC_(docptr, this->ioreg) & 1) {
1072     		printk("Error writing\n");
1073     		/* There was an error */
1074     		instr->state = MTD_ERASE_FAILED;
1075     	} else
1076     		instr->state = MTD_ERASE_DONE;
1077     
1078     	if (instr->callback)
1079     		instr->callback(instr);
1080     
1081     	return 0;
1082     }
1083     
1084     
1085     /****************************************************************************
1086      *
1087      * Module stuff
1088      *
1089      ****************************************************************************/
1090     
1091     #if LINUX_VERSION_CODE < 0x20212 && defined(MODULE)
1092     #define cleanup_doc2000 cleanup_module
1093     #define init_doc2000 init_module
1094     #endif
1095     
1096     int __init init_doc2000(void)
1097     {
1098            inter_module_register(im_name, THIS_MODULE, &DoC2k_init);
1099            return 0;
1100     }
1101     
1102     static void __exit cleanup_doc2000(void)
1103     {
1104     	struct mtd_info *mtd;
1105     	struct DiskOnChip *this;
1106     
1107     	while ((mtd = doc2klist)) {
1108     		this = (struct DiskOnChip *) mtd->priv;
1109     		doc2klist = this->nextdoc;
1110     
1111     		del_mtd_device(mtd);
1112     
1113     		iounmap((void *) this->virtadr);
1114     		kfree(this->chips);
1115     		kfree(mtd);
1116     	}
1117     	inter_module_unregister(im_name);
1118     }
1119     
1120     module_exit(cleanup_doc2000);
1121     module_init(init_doc2000);
1122