1// SPDX-License-Identifier: GPL-2.0-or-later
2/* Freescale Enhanced Local Bus Controller NAND driver
3 *
4 * Copyright © 2006-2007, 2010 Freescale Semiconductor
5 *
6 * Authors: Nick Spence <nick.spence@freescale.com>,
7 *          Scott Wood <scottwood@freescale.com>
8 *          Jack Lan <jack.lan@freescale.com>
9 *          Roy Zang <tie-fei.zang@freescale.com>
10 */
11
12#include <linux/module.h>
13#include <linux/types.h>
14#include <linux/kernel.h>
15#include <linux/string.h>
16#include <linux/ioport.h>
17#include <linux/of_address.h>
18#include <linux/of_platform.h>
19#include <linux/platform_device.h>
20#include <linux/slab.h>
21#include <linux/interrupt.h>
22
23#include <linux/mtd/mtd.h>
24#include <linux/mtd/rawnand.h>
25#include <linux/mtd/nand_ecc.h>
26#include <linux/mtd/partitions.h>
27
28#include <asm/io.h>
29#include <asm/fsl_lbc.h>
30
31#define MAX_BANKS 8
32#define ERR_BYTE 0xFF /* Value returned for read bytes when read failed */
33#define FCM_TIMEOUT_MSECS 500 /* Maximum number of mSecs to wait for FCM */
34
35/* mtd information per set */
36
37struct fsl_elbc_mtd {
38	struct nand_chip chip;
39	struct fsl_lbc_ctrl *ctrl;
40
41	struct device *dev;
42	int bank;               /* Chip select bank number           */
43	u8 __iomem *vbase;      /* Chip select base virtual address  */
44	int page_size;          /* NAND page size (0=512, 1=2048)    */
45	unsigned int fmr;       /* FCM Flash Mode Register value     */
46};
47
48/* Freescale eLBC FCM controller information */
49
50struct fsl_elbc_fcm_ctrl {
51	struct nand_controller controller;
52	struct fsl_elbc_mtd *chips[MAX_BANKS];
53
54	u8 __iomem *addr;        /* Address of assigned FCM buffer        */
55	unsigned int page;       /* Last page written to / read from      */
56	unsigned int read_bytes; /* Number of bytes read during command   */
57	unsigned int column;     /* Saved column from SEQIN               */
58	unsigned int index;      /* Pointer to next byte to 'read'        */
59	unsigned int status;     /* status read from LTESR after last op  */
60	unsigned int mdr;        /* UPM/FCM Data Register value           */
61	unsigned int use_mdr;    /* Non zero if the MDR is to be set      */
62	unsigned int oob;        /* Non zero if operating on OOB data     */
63	unsigned int counter;	 /* counter for the initializations	  */
64	unsigned int max_bitflips;  /* Saved during READ0 cmd		  */
65};
66
67/* These map to the positions used by the FCM hardware ECC generator */
68
69static int fsl_elbc_ooblayout_ecc(struct mtd_info *mtd, int section,
70				  struct mtd_oob_region *oobregion)
71{
72	struct nand_chip *chip = mtd_to_nand(mtd);
73	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
74
75	if (section >= chip->ecc.steps)
76		return -ERANGE;
77
78	oobregion->offset = (16 * section) + 6;
79	if (priv->fmr & FMR_ECCM)
80		oobregion->offset += 2;
81
82	oobregion->length = chip->ecc.bytes;
83
84	return 0;
85}
86
87static int fsl_elbc_ooblayout_free(struct mtd_info *mtd, int section,
88				   struct mtd_oob_region *oobregion)
89{
90	struct nand_chip *chip = mtd_to_nand(mtd);
91	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
92
93	if (section > chip->ecc.steps)
94		return -ERANGE;
95
96	if (!section) {
97		oobregion->offset = 0;
98		if (mtd->writesize > 512)
99			oobregion->offset++;
100		oobregion->length = (priv->fmr & FMR_ECCM) ? 7 : 5;
101	} else {
102		oobregion->offset = (16 * section) -
103				    ((priv->fmr & FMR_ECCM) ? 5 : 7);
104		if (section < chip->ecc.steps)
105			oobregion->length = 13;
106		else
107			oobregion->length = mtd->oobsize - oobregion->offset;
108	}
109
110	return 0;
111}
112
113static const struct mtd_ooblayout_ops fsl_elbc_ooblayout_ops = {
114	.ecc = fsl_elbc_ooblayout_ecc,
115	.free = fsl_elbc_ooblayout_free,
116};
117
118/*
119 * ELBC may use HW ECC, so that OOB offsets, that NAND core uses for bbt,
120 * interfere with ECC positions, that's why we implement our own descriptors.
121 * OOB {11, 5}, works for both SP and LP chips, with ECCM = 1 and ECCM = 0.
122 */
123static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
124static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
125
126static struct nand_bbt_descr bbt_main_descr = {
127	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
128		   NAND_BBT_2BIT | NAND_BBT_VERSION,
129	.offs =	11,
130	.len = 4,
131	.veroffs = 15,
132	.maxblocks = 4,
133	.pattern = bbt_pattern,
134};
135
136static struct nand_bbt_descr bbt_mirror_descr = {
137	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
138		   NAND_BBT_2BIT | NAND_BBT_VERSION,
139	.offs =	11,
140	.len = 4,
141	.veroffs = 15,
142	.maxblocks = 4,
143	.pattern = mirror_pattern,
144};
145
146/*=================================*/
147
148/*
149 * Set up the FCM hardware block and page address fields, and the fcm
150 * structure addr field to point to the correct FCM buffer in memory
151 */
152static void set_addr(struct mtd_info *mtd, int column, int page_addr, int oob)
153{
154	struct nand_chip *chip = mtd_to_nand(mtd);
155	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
156	struct fsl_lbc_ctrl *ctrl = priv->ctrl;
157	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
158	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
159	int buf_num;
160
161	elbc_fcm_ctrl->page = page_addr;
162
163	if (priv->page_size) {
164		/*
165		 * large page size chip : FPAR[PI] save the lowest 6 bits,
166		 *                        FBAR[BLK] save the other bits.
167		 */
168		out_be32(&lbc->fbar, page_addr >> 6);
169		out_be32(&lbc->fpar,
170		         ((page_addr << FPAR_LP_PI_SHIFT) & FPAR_LP_PI) |
171		         (oob ? FPAR_LP_MS : 0) | column);
172		buf_num = (page_addr & 1) << 2;
173	} else {
174		/*
175		 * small page size chip : FPAR[PI] save the lowest 5 bits,
176		 *                        FBAR[BLK] save the other bits.
177		 */
178		out_be32(&lbc->fbar, page_addr >> 5);
179		out_be32(&lbc->fpar,
180		         ((page_addr << FPAR_SP_PI_SHIFT) & FPAR_SP_PI) |
181		         (oob ? FPAR_SP_MS : 0) | column);
182		buf_num = page_addr & 7;
183	}
184
185	elbc_fcm_ctrl->addr = priv->vbase + buf_num * 1024;
186	elbc_fcm_ctrl->index = column;
187
188	/* for OOB data point to the second half of the buffer */
189	if (oob)
190		elbc_fcm_ctrl->index += priv->page_size ? 2048 : 512;
191
192	dev_vdbg(priv->dev, "set_addr: bank=%d, "
193			    "elbc_fcm_ctrl->addr=0x%p (0x%p), "
194	                    "index %x, pes %d ps %d\n",
195		 buf_num, elbc_fcm_ctrl->addr, priv->vbase,
196		 elbc_fcm_ctrl->index,
197	         chip->phys_erase_shift, chip->page_shift);
198}
199
200/*
201 * execute FCM command and wait for it to complete
202 */
203static int fsl_elbc_run_command(struct mtd_info *mtd)
204{
205	struct nand_chip *chip = mtd_to_nand(mtd);
206	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
207	struct fsl_lbc_ctrl *ctrl = priv->ctrl;
208	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
209	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
210
211	/* Setup the FMR[OP] to execute without write protection */
212	out_be32(&lbc->fmr, priv->fmr | 3);
213	if (elbc_fcm_ctrl->use_mdr)
214		out_be32(&lbc->mdr, elbc_fcm_ctrl->mdr);
215
216	dev_vdbg(priv->dev,
217	         "fsl_elbc_run_command: fmr=%08x fir=%08x fcr=%08x\n",
218	         in_be32(&lbc->fmr), in_be32(&lbc->fir), in_be32(&lbc->fcr));
219	dev_vdbg(priv->dev,
220	         "fsl_elbc_run_command: fbar=%08x fpar=%08x "
221	         "fbcr=%08x bank=%d\n",
222	         in_be32(&lbc->fbar), in_be32(&lbc->fpar),
223	         in_be32(&lbc->fbcr), priv->bank);
224
225	ctrl->irq_status = 0;
226	/* execute special operation */
227	out_be32(&lbc->lsor, priv->bank);
228
229	/* wait for FCM complete flag or timeout */
230	wait_event_timeout(ctrl->irq_wait, ctrl->irq_status,
231	                   FCM_TIMEOUT_MSECS * HZ/1000);
232	elbc_fcm_ctrl->status = ctrl->irq_status;
233	/* store mdr value in case it was needed */
234	if (elbc_fcm_ctrl->use_mdr)
235		elbc_fcm_ctrl->mdr = in_be32(&lbc->mdr);
236
237	elbc_fcm_ctrl->use_mdr = 0;
238
239	if (elbc_fcm_ctrl->status != LTESR_CC) {
240		dev_info(priv->dev,
241		         "command failed: fir %x fcr %x status %x mdr %x\n",
242		         in_be32(&lbc->fir), in_be32(&lbc->fcr),
243			 elbc_fcm_ctrl->status, elbc_fcm_ctrl->mdr);
244		return -EIO;
245	}
246
247	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
248		return 0;
249
250	elbc_fcm_ctrl->max_bitflips = 0;
251
252	if (elbc_fcm_ctrl->read_bytes == mtd->writesize + mtd->oobsize) {
253		uint32_t lteccr = in_be32(&lbc->lteccr);
254		/*
255		 * if command was a full page read and the ELBC
256		 * has the LTECCR register, then bits 12-15 (ppc order) of
257		 * LTECCR indicates which 512 byte sub-pages had fixed errors.
258		 * bits 28-31 are uncorrectable errors, marked elsewhere.
259		 * for small page nand only 1 bit is used.
260		 * if the ELBC doesn't have the lteccr register it reads 0
261		 * FIXME: 4 bits can be corrected on NANDs with 2k pages, so
262		 * count the number of sub-pages with bitflips and update
263		 * ecc_stats.corrected accordingly.
264		 */
265		if (lteccr & 0x000F000F)
266			out_be32(&lbc->lteccr, 0x000F000F); /* clear lteccr */
267		if (lteccr & 0x000F0000) {
268			mtd->ecc_stats.corrected++;
269			elbc_fcm_ctrl->max_bitflips = 1;
270		}
271	}
272
273	return 0;
274}
275
276static void fsl_elbc_do_read(struct nand_chip *chip, int oob)
277{
278	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
279	struct fsl_lbc_ctrl *ctrl = priv->ctrl;
280	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
281
282	if (priv->page_size) {
283		out_be32(&lbc->fir,
284		         (FIR_OP_CM0 << FIR_OP0_SHIFT) |
285		         (FIR_OP_CA  << FIR_OP1_SHIFT) |
286		         (FIR_OP_PA  << FIR_OP2_SHIFT) |
287		         (FIR_OP_CM1 << FIR_OP3_SHIFT) |
288		         (FIR_OP_RBW << FIR_OP4_SHIFT));
289
290		out_be32(&lbc->fcr, (NAND_CMD_READ0 << FCR_CMD0_SHIFT) |
291		                    (NAND_CMD_READSTART << FCR_CMD1_SHIFT));
292	} else {
293		out_be32(&lbc->fir,
294		         (FIR_OP_CM0 << FIR_OP0_SHIFT) |
295		         (FIR_OP_CA  << FIR_OP1_SHIFT) |
296		         (FIR_OP_PA  << FIR_OP2_SHIFT) |
297		         (FIR_OP_RBW << FIR_OP3_SHIFT));
298
299		if (oob)
300			out_be32(&lbc->fcr, NAND_CMD_READOOB << FCR_CMD0_SHIFT);
301		else
302			out_be32(&lbc->fcr, NAND_CMD_READ0 << FCR_CMD0_SHIFT);
303	}
304}
305
306/* cmdfunc send commands to the FCM */
307static void fsl_elbc_cmdfunc(struct nand_chip *chip, unsigned int command,
308                             int column, int page_addr)
309{
310	struct mtd_info *mtd = nand_to_mtd(chip);
311	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
312	struct fsl_lbc_ctrl *ctrl = priv->ctrl;
313	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
314	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
315
316	elbc_fcm_ctrl->use_mdr = 0;
317
318	/* clear the read buffer */
319	elbc_fcm_ctrl->read_bytes = 0;
320	if (command != NAND_CMD_PAGEPROG)
321		elbc_fcm_ctrl->index = 0;
322
323	switch (command) {
324	/* READ0 and READ1 read the entire buffer to use hardware ECC. */
325	case NAND_CMD_READ1:
326		column += 256;
327		fallthrough;
328	case NAND_CMD_READ0:
329		dev_dbg(priv->dev,
330		        "fsl_elbc_cmdfunc: NAND_CMD_READ0, page_addr:"
331		        " 0x%x, column: 0x%x.\n", page_addr, column);
332
333
334		out_be32(&lbc->fbcr, 0); /* read entire page to enable ECC */
335		set_addr(mtd, 0, page_addr, 0);
336
337		elbc_fcm_ctrl->read_bytes = mtd->writesize + mtd->oobsize;
338		elbc_fcm_ctrl->index += column;
339
340		fsl_elbc_do_read(chip, 0);
341		fsl_elbc_run_command(mtd);
342		return;
343
344	/* RNDOUT moves the pointer inside the page */
345	case NAND_CMD_RNDOUT:
346		dev_dbg(priv->dev,
347			"fsl_elbc_cmdfunc: NAND_CMD_RNDOUT, column: 0x%x.\n",
348			column);
349
350		elbc_fcm_ctrl->index = column;
351		return;
352
353	/* READOOB reads only the OOB because no ECC is performed. */
354	case NAND_CMD_READOOB:
355		dev_vdbg(priv->dev,
356		         "fsl_elbc_cmdfunc: NAND_CMD_READOOB, page_addr:"
357			 " 0x%x, column: 0x%x.\n", page_addr, column);
358
359		out_be32(&lbc->fbcr, mtd->oobsize - column);
360		set_addr(mtd, column, page_addr, 1);
361
362		elbc_fcm_ctrl->read_bytes = mtd->writesize + mtd->oobsize;
363
364		fsl_elbc_do_read(chip, 1);
365		fsl_elbc_run_command(mtd);
366		return;
367
368	case NAND_CMD_READID:
369	case NAND_CMD_PARAM:
370		dev_vdbg(priv->dev, "fsl_elbc_cmdfunc: NAND_CMD %x\n", command);
371
372		out_be32(&lbc->fir, (FIR_OP_CM0 << FIR_OP0_SHIFT) |
373		                    (FIR_OP_UA  << FIR_OP1_SHIFT) |
374		                    (FIR_OP_RBW << FIR_OP2_SHIFT));
375		out_be32(&lbc->fcr, command << FCR_CMD0_SHIFT);
376		/*
377		 * although currently it's 8 bytes for READID, we always read
378		 * the maximum 256 bytes(for PARAM)
379		 */
380		out_be32(&lbc->fbcr, 256);
381		elbc_fcm_ctrl->read_bytes = 256;
382		elbc_fcm_ctrl->use_mdr = 1;
383		elbc_fcm_ctrl->mdr = column;
384		set_addr(mtd, 0, 0, 0);
385		fsl_elbc_run_command(mtd);
386		return;
387
388	/* ERASE1 stores the block and page address */
389	case NAND_CMD_ERASE1:
390		dev_vdbg(priv->dev,
391		         "fsl_elbc_cmdfunc: NAND_CMD_ERASE1, "
392		         "page_addr: 0x%x.\n", page_addr);
393		set_addr(mtd, 0, page_addr, 0);
394		return;
395
396	/* ERASE2 uses the block and page address from ERASE1 */
397	case NAND_CMD_ERASE2:
398		dev_vdbg(priv->dev, "fsl_elbc_cmdfunc: NAND_CMD_ERASE2.\n");
399
400		out_be32(&lbc->fir,
401		         (FIR_OP_CM0 << FIR_OP0_SHIFT) |
402		         (FIR_OP_PA  << FIR_OP1_SHIFT) |
403		         (FIR_OP_CM2 << FIR_OP2_SHIFT) |
404		         (FIR_OP_CW1 << FIR_OP3_SHIFT) |
405		         (FIR_OP_RS  << FIR_OP4_SHIFT));
406
407		out_be32(&lbc->fcr,
408		         (NAND_CMD_ERASE1 << FCR_CMD0_SHIFT) |
409		         (NAND_CMD_STATUS << FCR_CMD1_SHIFT) |
410		         (NAND_CMD_ERASE2 << FCR_CMD2_SHIFT));
411
412		out_be32(&lbc->fbcr, 0);
413		elbc_fcm_ctrl->read_bytes = 0;
414		elbc_fcm_ctrl->use_mdr = 1;
415
416		fsl_elbc_run_command(mtd);
417		return;
418
419	/* SEQIN sets up the addr buffer and all registers except the length */
420	case NAND_CMD_SEQIN: {
421		__be32 fcr;
422		dev_vdbg(priv->dev,
423			 "fsl_elbc_cmdfunc: NAND_CMD_SEQIN/PAGE_PROG, "
424		         "page_addr: 0x%x, column: 0x%x.\n",
425		         page_addr, column);
426
427		elbc_fcm_ctrl->column = column;
428		elbc_fcm_ctrl->use_mdr = 1;
429
430		if (column >= mtd->writesize) {
431			/* OOB area */
432			column -= mtd->writesize;
433			elbc_fcm_ctrl->oob = 1;
434		} else {
435			WARN_ON(column != 0);
436			elbc_fcm_ctrl->oob = 0;
437		}
438
439		fcr = (NAND_CMD_STATUS   << FCR_CMD1_SHIFT) |
440		      (NAND_CMD_SEQIN    << FCR_CMD2_SHIFT) |
441		      (NAND_CMD_PAGEPROG << FCR_CMD3_SHIFT);
442
443		if (priv->page_size) {
444			out_be32(&lbc->fir,
445			         (FIR_OP_CM2 << FIR_OP0_SHIFT) |
446			         (FIR_OP_CA  << FIR_OP1_SHIFT) |
447			         (FIR_OP_PA  << FIR_OP2_SHIFT) |
448			         (FIR_OP_WB  << FIR_OP3_SHIFT) |
449			         (FIR_OP_CM3 << FIR_OP4_SHIFT) |
450			         (FIR_OP_CW1 << FIR_OP5_SHIFT) |
451			         (FIR_OP_RS  << FIR_OP6_SHIFT));
452		} else {
453			out_be32(&lbc->fir,
454			         (FIR_OP_CM0 << FIR_OP0_SHIFT) |
455			         (FIR_OP_CM2 << FIR_OP1_SHIFT) |
456			         (FIR_OP_CA  << FIR_OP2_SHIFT) |
457			         (FIR_OP_PA  << FIR_OP3_SHIFT) |
458			         (FIR_OP_WB  << FIR_OP4_SHIFT) |
459			         (FIR_OP_CM3 << FIR_OP5_SHIFT) |
460			         (FIR_OP_CW1 << FIR_OP6_SHIFT) |
461			         (FIR_OP_RS  << FIR_OP7_SHIFT));
462
463			if (elbc_fcm_ctrl->oob)
464				/* OOB area --> READOOB */
465				fcr |= NAND_CMD_READOOB << FCR_CMD0_SHIFT;
466			else
467				/* First 256 bytes --> READ0 */
468				fcr |= NAND_CMD_READ0 << FCR_CMD0_SHIFT;
469		}
470
471		out_be32(&lbc->fcr, fcr);
472		set_addr(mtd, column, page_addr, elbc_fcm_ctrl->oob);
473		return;
474	}
475
476	/* PAGEPROG reuses all of the setup from SEQIN and adds the length */
477	case NAND_CMD_PAGEPROG: {
478		dev_vdbg(priv->dev,
479		         "fsl_elbc_cmdfunc: NAND_CMD_PAGEPROG "
480			 "writing %d bytes.\n", elbc_fcm_ctrl->index);
481
482		/* if the write did not start at 0 or is not a full page
483		 * then set the exact length, otherwise use a full page
484		 * write so the HW generates the ECC.
485		 */
486		if (elbc_fcm_ctrl->oob || elbc_fcm_ctrl->column != 0 ||
487		    elbc_fcm_ctrl->index != mtd->writesize + mtd->oobsize)
488			out_be32(&lbc->fbcr,
489				elbc_fcm_ctrl->index - elbc_fcm_ctrl->column);
490		else
491			out_be32(&lbc->fbcr, 0);
492
493		fsl_elbc_run_command(mtd);
494		return;
495	}
496
497	/* CMD_STATUS must read the status byte while CEB is active */
498	/* Note - it does not wait for the ready line */
499	case NAND_CMD_STATUS:
500		out_be32(&lbc->fir,
501		         (FIR_OP_CM0 << FIR_OP0_SHIFT) |
502		         (FIR_OP_RBW << FIR_OP1_SHIFT));
503		out_be32(&lbc->fcr, NAND_CMD_STATUS << FCR_CMD0_SHIFT);
504		out_be32(&lbc->fbcr, 1);
505		set_addr(mtd, 0, 0, 0);
506		elbc_fcm_ctrl->read_bytes = 1;
507
508		fsl_elbc_run_command(mtd);
509
510		/* The chip always seems to report that it is
511		 * write-protected, even when it is not.
512		 */
513		setbits8(elbc_fcm_ctrl->addr, NAND_STATUS_WP);
514		return;
515
516	/* RESET without waiting for the ready line */
517	case NAND_CMD_RESET:
518		dev_dbg(priv->dev, "fsl_elbc_cmdfunc: NAND_CMD_RESET.\n");
519		out_be32(&lbc->fir, FIR_OP_CM0 << FIR_OP0_SHIFT);
520		out_be32(&lbc->fcr, NAND_CMD_RESET << FCR_CMD0_SHIFT);
521		fsl_elbc_run_command(mtd);
522		return;
523
524	default:
525		dev_err(priv->dev,
526		        "fsl_elbc_cmdfunc: error, unsupported command 0x%x.\n",
527		        command);
528	}
529}
530
531static void fsl_elbc_select_chip(struct nand_chip *chip, int cs)
532{
533	/* The hardware does not seem to support multiple
534	 * chips per bank.
535	 */
536}
537
538/*
539 * Write buf to the FCM Controller Data Buffer
540 */
541static void fsl_elbc_write_buf(struct nand_chip *chip, const u8 *buf, int len)
542{
543	struct mtd_info *mtd = nand_to_mtd(chip);
544	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
545	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
546	unsigned int bufsize = mtd->writesize + mtd->oobsize;
547
548	if (len <= 0) {
549		dev_err(priv->dev, "write_buf of %d bytes", len);
550		elbc_fcm_ctrl->status = 0;
551		return;
552	}
553
554	if ((unsigned int)len > bufsize - elbc_fcm_ctrl->index) {
555		dev_err(priv->dev,
556		        "write_buf beyond end of buffer "
557		        "(%d requested, %u available)\n",
558			len, bufsize - elbc_fcm_ctrl->index);
559		len = bufsize - elbc_fcm_ctrl->index;
560	}
561
562	memcpy_toio(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index], buf, len);
563	/*
564	 * This is workaround for the weird elbc hangs during nand write,
565	 * Scott Wood says: "...perhaps difference in how long it takes a
566	 * write to make it through the localbus compared to a write to IMMR
567	 * is causing problems, and sync isn't helping for some reason."
568	 * Reading back the last byte helps though.
569	 */
570	in_8(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index] + len - 1);
571
572	elbc_fcm_ctrl->index += len;
573}
574
575/*
576 * read a byte from either the FCM hardware buffer if it has any data left
577 * otherwise issue a command to read a single byte.
578 */
579static u8 fsl_elbc_read_byte(struct nand_chip *chip)
580{
581	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
582	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
583
584	/* If there are still bytes in the FCM, then use the next byte. */
585	if (elbc_fcm_ctrl->index < elbc_fcm_ctrl->read_bytes)
586		return in_8(&elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index++]);
587
588	dev_err(priv->dev, "read_byte beyond end of buffer\n");
589	return ERR_BYTE;
590}
591
592/*
593 * Read from the FCM Controller Data Buffer
594 */
595static void fsl_elbc_read_buf(struct nand_chip *chip, u8 *buf, int len)
596{
597	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
598	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
599	int avail;
600
601	if (len < 0)
602		return;
603
604	avail = min((unsigned int)len,
605			elbc_fcm_ctrl->read_bytes - elbc_fcm_ctrl->index);
606	memcpy_fromio(buf, &elbc_fcm_ctrl->addr[elbc_fcm_ctrl->index], avail);
607	elbc_fcm_ctrl->index += avail;
608
609	if (len > avail)
610		dev_err(priv->dev,
611		        "read_buf beyond end of buffer "
612		        "(%d requested, %d available)\n",
613		        len, avail);
614}
615
616/* This function is called after Program and Erase Operations to
617 * check for success or failure.
618 */
619static int fsl_elbc_wait(struct nand_chip *chip)
620{
621	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
622	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
623
624	if (elbc_fcm_ctrl->status != LTESR_CC)
625		return NAND_STATUS_FAIL;
626
627	/* The chip always seems to report that it is
628	 * write-protected, even when it is not.
629	 */
630	return (elbc_fcm_ctrl->mdr & 0xff) | NAND_STATUS_WP;
631}
632
633static int fsl_elbc_read_page(struct nand_chip *chip, uint8_t *buf,
634			      int oob_required, int page)
635{
636	struct mtd_info *mtd = nand_to_mtd(chip);
637	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
638	struct fsl_lbc_ctrl *ctrl = priv->ctrl;
639	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
640
641	nand_read_page_op(chip, page, 0, buf, mtd->writesize);
642	if (oob_required)
643		fsl_elbc_read_buf(chip, chip->oob_poi, mtd->oobsize);
644
645	if (fsl_elbc_wait(chip) & NAND_STATUS_FAIL)
646		mtd->ecc_stats.failed++;
647
648	return elbc_fcm_ctrl->max_bitflips;
649}
650
651/* ECC will be calculated automatically, and errors will be detected in
652 * waitfunc.
653 */
654static int fsl_elbc_write_page(struct nand_chip *chip, const uint8_t *buf,
655			       int oob_required, int page)
656{
657	struct mtd_info *mtd = nand_to_mtd(chip);
658
659	nand_prog_page_begin_op(chip, page, 0, buf, mtd->writesize);
660	fsl_elbc_write_buf(chip, chip->oob_poi, mtd->oobsize);
661
662	return nand_prog_page_end_op(chip);
663}
664
665/* ECC will be calculated automatically, and errors will be detected in
666 * waitfunc.
667 */
668static int fsl_elbc_write_subpage(struct nand_chip *chip, uint32_t offset,
669				  uint32_t data_len, const uint8_t *buf,
670				  int oob_required, int page)
671{
672	struct mtd_info *mtd = nand_to_mtd(chip);
673
674	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
675	fsl_elbc_write_buf(chip, buf, mtd->writesize);
676	fsl_elbc_write_buf(chip, chip->oob_poi, mtd->oobsize);
677	return nand_prog_page_end_op(chip);
678}
679
680static int fsl_elbc_chip_init(struct fsl_elbc_mtd *priv)
681{
682	struct fsl_lbc_ctrl *ctrl = priv->ctrl;
683	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
684	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = ctrl->nand;
685	struct nand_chip *chip = &priv->chip;
686	struct mtd_info *mtd = nand_to_mtd(chip);
687
688	dev_dbg(priv->dev, "eLBC Set Information for bank %d\n", priv->bank);
689
690	/* Fill in fsl_elbc_mtd structure */
691	mtd->dev.parent = priv->dev;
692	nand_set_flash_node(chip, priv->dev->of_node);
693
694	/* set timeout to maximum */
695	priv->fmr = 15 << FMR_CWTO_SHIFT;
696	if (in_be32(&lbc->bank[priv->bank].or) & OR_FCM_PGS)
697		priv->fmr |= FMR_ECCM;
698
699	/* fill in nand_chip structure */
700	/* set up function call table */
701	chip->legacy.read_byte = fsl_elbc_read_byte;
702	chip->legacy.write_buf = fsl_elbc_write_buf;
703	chip->legacy.read_buf = fsl_elbc_read_buf;
704	chip->legacy.select_chip = fsl_elbc_select_chip;
705	chip->legacy.cmdfunc = fsl_elbc_cmdfunc;
706	chip->legacy.waitfunc = fsl_elbc_wait;
707	chip->legacy.set_features = nand_get_set_features_notsupp;
708	chip->legacy.get_features = nand_get_set_features_notsupp;
709
710	chip->bbt_td = &bbt_main_descr;
711	chip->bbt_md = &bbt_mirror_descr;
712
713	/* set up nand options */
714	chip->bbt_options = NAND_BBT_USE_FLASH;
715
716	chip->controller = &elbc_fcm_ctrl->controller;
717	nand_set_controller_data(chip, priv);
718
719	return 0;
720}
721
722static int fsl_elbc_attach_chip(struct nand_chip *chip)
723{
724	struct mtd_info *mtd = nand_to_mtd(chip);
725	struct fsl_elbc_mtd *priv = nand_get_controller_data(chip);
726	struct fsl_lbc_ctrl *ctrl = priv->ctrl;
727	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
728	unsigned int al;
729
730	/*
731	 * if ECC was not chosen in DT, decide whether to use HW or SW ECC from
732	 * CS Base Register
733	 */
734	if (chip->ecc.engine_type == NAND_ECC_ENGINE_TYPE_INVALID) {
735		/* If CS Base Register selects full hardware ECC then use it */
736		if ((in_be32(&lbc->bank[priv->bank].br) & BR_DECC) ==
737		    BR_DECC_CHK_GEN) {
738			chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
739		} else {
740			/* otherwise fall back to default software ECC */
741			chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
742			chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
743		}
744	}
745
746	switch (chip->ecc.engine_type) {
747	/* if HW ECC was chosen, setup ecc and oob layout */
748	case NAND_ECC_ENGINE_TYPE_ON_HOST:
749		chip->ecc.read_page = fsl_elbc_read_page;
750		chip->ecc.write_page = fsl_elbc_write_page;
751		chip->ecc.write_subpage = fsl_elbc_write_subpage;
752		mtd_set_ooblayout(mtd, &fsl_elbc_ooblayout_ops);
753		chip->ecc.size = 512;
754		chip->ecc.bytes = 3;
755		chip->ecc.strength = 1;
756		break;
757
758	/* if none or SW ECC was chosen, we do not need to set anything here */
759	case NAND_ECC_ENGINE_TYPE_NONE:
760	case NAND_ECC_ENGINE_TYPE_SOFT:
761	case NAND_ECC_ENGINE_TYPE_ON_DIE:
762		break;
763
764	default:
765		return -EINVAL;
766	}
767
768	/* calculate FMR Address Length field */
769	al = 0;
770	if (chip->pagemask & 0xffff0000)
771		al++;
772	if (chip->pagemask & 0xff000000)
773		al++;
774
775	priv->fmr |= al << FMR_AL_SHIFT;
776
777	dev_dbg(priv->dev, "fsl_elbc_init: nand->numchips = %d\n",
778	        nanddev_ntargets(&chip->base));
779	dev_dbg(priv->dev, "fsl_elbc_init: nand->chipsize = %lld\n",
780	        nanddev_target_size(&chip->base));
781	dev_dbg(priv->dev, "fsl_elbc_init: nand->pagemask = %8x\n",
782	        chip->pagemask);
783	dev_dbg(priv->dev, "fsl_elbc_init: nand->legacy.chip_delay = %d\n",
784	        chip->legacy.chip_delay);
785	dev_dbg(priv->dev, "fsl_elbc_init: nand->badblockpos = %d\n",
786	        chip->badblockpos);
787	dev_dbg(priv->dev, "fsl_elbc_init: nand->chip_shift = %d\n",
788	        chip->chip_shift);
789	dev_dbg(priv->dev, "fsl_elbc_init: nand->page_shift = %d\n",
790	        chip->page_shift);
791	dev_dbg(priv->dev, "fsl_elbc_init: nand->phys_erase_shift = %d\n",
792	        chip->phys_erase_shift);
793	dev_dbg(priv->dev, "fsl_elbc_init: nand->ecc.engine_type = %d\n",
794		chip->ecc.engine_type);
795	dev_dbg(priv->dev, "fsl_elbc_init: nand->ecc.steps = %d\n",
796	        chip->ecc.steps);
797	dev_dbg(priv->dev, "fsl_elbc_init: nand->ecc.bytes = %d\n",
798	        chip->ecc.bytes);
799	dev_dbg(priv->dev, "fsl_elbc_init: nand->ecc.total = %d\n",
800	        chip->ecc.total);
801	dev_dbg(priv->dev, "fsl_elbc_init: mtd->ooblayout = %p\n",
802		mtd->ooblayout);
803	dev_dbg(priv->dev, "fsl_elbc_init: mtd->flags = %08x\n", mtd->flags);
804	dev_dbg(priv->dev, "fsl_elbc_init: mtd->size = %lld\n", mtd->size);
805	dev_dbg(priv->dev, "fsl_elbc_init: mtd->erasesize = %d\n",
806	        mtd->erasesize);
807	dev_dbg(priv->dev, "fsl_elbc_init: mtd->writesize = %d\n",
808	        mtd->writesize);
809	dev_dbg(priv->dev, "fsl_elbc_init: mtd->oobsize = %d\n",
810	        mtd->oobsize);
811
812	/* adjust Option Register and ECC to match Flash page size */
813	if (mtd->writesize == 512) {
814		priv->page_size = 0;
815		clrbits32(&lbc->bank[priv->bank].or, OR_FCM_PGS);
816	} else if (mtd->writesize == 2048) {
817		priv->page_size = 1;
818		setbits32(&lbc->bank[priv->bank].or, OR_FCM_PGS);
819	} else {
820		dev_err(priv->dev,
821		        "fsl_elbc_init: page size %d is not supported\n",
822		        mtd->writesize);
823		return -ENOTSUPP;
824	}
825
826	return 0;
827}
828
829static const struct nand_controller_ops fsl_elbc_controller_ops = {
830	.attach_chip = fsl_elbc_attach_chip,
831};
832
833static int fsl_elbc_chip_remove(struct fsl_elbc_mtd *priv)
834{
835	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = priv->ctrl->nand;
836	struct mtd_info *mtd = nand_to_mtd(&priv->chip);
837
838	kfree(mtd->name);
839
840	if (priv->vbase)
841		iounmap(priv->vbase);
842
843	elbc_fcm_ctrl->chips[priv->bank] = NULL;
844	kfree(priv);
845	return 0;
846}
847
848static DEFINE_MUTEX(fsl_elbc_nand_mutex);
849
850static int fsl_elbc_nand_probe(struct platform_device *pdev)
851{
852	struct fsl_lbc_regs __iomem *lbc;
853	struct fsl_elbc_mtd *priv;
854	struct resource res;
855	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl;
856	static const char *part_probe_types[]
857		= { "cmdlinepart", "RedBoot", "ofpart", NULL };
858	int ret;
859	int bank;
860	struct device *dev;
861	struct device_node *node = pdev->dev.of_node;
862	struct mtd_info *mtd;
863
864	if (!fsl_lbc_ctrl_dev || !fsl_lbc_ctrl_dev->regs)
865		return -ENODEV;
866	lbc = fsl_lbc_ctrl_dev->regs;
867	dev = fsl_lbc_ctrl_dev->dev;
868
869	/* get, allocate and map the memory resource */
870	ret = of_address_to_resource(node, 0, &res);
871	if (ret) {
872		dev_err(dev, "failed to get resource\n");
873		return ret;
874	}
875
876	/* find which chip select it is connected to */
877	for (bank = 0; bank < MAX_BANKS; bank++)
878		if ((in_be32(&lbc->bank[bank].br) & BR_V) &&
879		    (in_be32(&lbc->bank[bank].br) & BR_MSEL) == BR_MS_FCM &&
880		    (in_be32(&lbc->bank[bank].br) &
881		     in_be32(&lbc->bank[bank].or) & BR_BA)
882		     == fsl_lbc_addr(res.start))
883			break;
884
885	if (bank >= MAX_BANKS) {
886		dev_err(dev, "address did not match any chip selects\n");
887		return -ENODEV;
888	}
889
890	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
891	if (!priv)
892		return -ENOMEM;
893
894	mutex_lock(&fsl_elbc_nand_mutex);
895	if (!fsl_lbc_ctrl_dev->nand) {
896		elbc_fcm_ctrl = kzalloc(sizeof(*elbc_fcm_ctrl), GFP_KERNEL);
897		if (!elbc_fcm_ctrl) {
898			mutex_unlock(&fsl_elbc_nand_mutex);
899			ret = -ENOMEM;
900			goto err;
901		}
902		elbc_fcm_ctrl->counter++;
903
904		nand_controller_init(&elbc_fcm_ctrl->controller);
905		fsl_lbc_ctrl_dev->nand = elbc_fcm_ctrl;
906	} else {
907		elbc_fcm_ctrl = fsl_lbc_ctrl_dev->nand;
908	}
909	mutex_unlock(&fsl_elbc_nand_mutex);
910
911	elbc_fcm_ctrl->chips[bank] = priv;
912	priv->bank = bank;
913	priv->ctrl = fsl_lbc_ctrl_dev;
914	priv->dev = &pdev->dev;
915	dev_set_drvdata(priv->dev, priv);
916
917	priv->vbase = ioremap(res.start, resource_size(&res));
918	if (!priv->vbase) {
919		dev_err(dev, "failed to map chip region\n");
920		ret = -ENOMEM;
921		goto err;
922	}
923
924	mtd = nand_to_mtd(&priv->chip);
925	mtd->name = kasprintf(GFP_KERNEL, "%llx.flash", (u64)res.start);
926	if (!nand_to_mtd(&priv->chip)->name) {
927		ret = -ENOMEM;
928		goto err;
929	}
930
931	ret = fsl_elbc_chip_init(priv);
932	if (ret)
933		goto err;
934
935	priv->chip.controller->ops = &fsl_elbc_controller_ops;
936	ret = nand_scan(&priv->chip, 1);
937	if (ret)
938		goto err;
939
940	/* First look for RedBoot table or partitions on the command
941	 * line, these take precedence over device tree information */
942	ret = mtd_device_parse_register(mtd, part_probe_types, NULL, NULL, 0);
943	if (ret)
944		goto cleanup_nand;
945
946	pr_info("eLBC NAND device at 0x%llx, bank %d\n",
947		(unsigned long long)res.start, priv->bank);
948
949	return 0;
950
951cleanup_nand:
952	nand_cleanup(&priv->chip);
953err:
954	fsl_elbc_chip_remove(priv);
955
956	return ret;
957}
958
959static int fsl_elbc_nand_remove(struct platform_device *pdev)
960{
961	struct fsl_elbc_fcm_ctrl *elbc_fcm_ctrl = fsl_lbc_ctrl_dev->nand;
962	struct fsl_elbc_mtd *priv = dev_get_drvdata(&pdev->dev);
963	struct nand_chip *chip = &priv->chip;
964	int ret;
965
966	ret = mtd_device_unregister(nand_to_mtd(chip));
967	WARN_ON(ret);
968	nand_cleanup(chip);
969
970	fsl_elbc_chip_remove(priv);
971
972	mutex_lock(&fsl_elbc_nand_mutex);
973	elbc_fcm_ctrl->counter--;
974	if (!elbc_fcm_ctrl->counter) {
975		fsl_lbc_ctrl_dev->nand = NULL;
976		kfree(elbc_fcm_ctrl);
977	}
978	mutex_unlock(&fsl_elbc_nand_mutex);
979
980	return 0;
981
982}
983
984static const struct of_device_id fsl_elbc_nand_match[] = {
985	{ .compatible = "fsl,elbc-fcm-nand", },
986	{}
987};
988MODULE_DEVICE_TABLE(of, fsl_elbc_nand_match);
989
990static struct platform_driver fsl_elbc_nand_driver = {
991	.driver = {
992		.name = "fsl,elbc-fcm-nand",
993		.of_match_table = fsl_elbc_nand_match,
994	},
995	.probe = fsl_elbc_nand_probe,
996	.remove = fsl_elbc_nand_remove,
997};
998
999module_platform_driver(fsl_elbc_nand_driver);
1000
1001MODULE_LICENSE("GPL");
1002MODULE_AUTHOR("Freescale");
1003MODULE_DESCRIPTION("Freescale Enhanced Local Bus Controller MTD NAND driver");
1004