xref: /openbmc/linux/drivers/mtd/nand/raw/lpc32xx_mlc.c (revision 96de2506)
1 /*
2  * Driver for NAND MLC Controller in LPC32xx
3  *
4  * Author: Roland Stigge <stigge@antcom.de>
5  *
6  * Copyright © 2011 WORK Microwave GmbH
7  * Copyright © 2011, 2012 Roland Stigge
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  *
20  * NAND Flash Controller Operation:
21  * - Read: Auto Decode
22  * - Write: Auto Encode
23  * - Tested Page Sizes: 2048, 4096
24  */
25 
26 #include <linux/slab.h>
27 #include <linux/module.h>
28 #include <linux/platform_device.h>
29 #include <linux/mtd/mtd.h>
30 #include <linux/mtd/rawnand.h>
31 #include <linux/mtd/partitions.h>
32 #include <linux/clk.h>
33 #include <linux/err.h>
34 #include <linux/delay.h>
35 #include <linux/completion.h>
36 #include <linux/interrupt.h>
37 #include <linux/of.h>
38 #include <linux/of_gpio.h>
39 #include <linux/mtd/lpc32xx_mlc.h>
40 #include <linux/io.h>
41 #include <linux/mm.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/dmaengine.h>
44 #include <linux/mtd/nand_ecc.h>
45 
46 #define DRV_NAME "lpc32xx_mlc"
47 
48 /**********************************************************************
49 * MLC NAND controller register offsets
50 **********************************************************************/
51 
52 #define MLC_BUFF(x)			(x + 0x00000)
53 #define MLC_DATA(x)			(x + 0x08000)
54 #define MLC_CMD(x)			(x + 0x10000)
55 #define MLC_ADDR(x)			(x + 0x10004)
56 #define MLC_ECC_ENC_REG(x)		(x + 0x10008)
57 #define MLC_ECC_DEC_REG(x)		(x + 0x1000C)
58 #define MLC_ECC_AUTO_ENC_REG(x)		(x + 0x10010)
59 #define MLC_ECC_AUTO_DEC_REG(x)		(x + 0x10014)
60 #define MLC_RPR(x)			(x + 0x10018)
61 #define MLC_WPR(x)			(x + 0x1001C)
62 #define MLC_RUBP(x)			(x + 0x10020)
63 #define MLC_ROBP(x)			(x + 0x10024)
64 #define MLC_SW_WP_ADD_LOW(x)		(x + 0x10028)
65 #define MLC_SW_WP_ADD_HIG(x)		(x + 0x1002C)
66 #define MLC_ICR(x)			(x + 0x10030)
67 #define MLC_TIME_REG(x)			(x + 0x10034)
68 #define MLC_IRQ_MR(x)			(x + 0x10038)
69 #define MLC_IRQ_SR(x)			(x + 0x1003C)
70 #define MLC_LOCK_PR(x)			(x + 0x10044)
71 #define MLC_ISR(x)			(x + 0x10048)
72 #define MLC_CEH(x)			(x + 0x1004C)
73 
74 /**********************************************************************
75 * MLC_CMD bit definitions
76 **********************************************************************/
77 #define MLCCMD_RESET			0xFF
78 
79 /**********************************************************************
80 * MLC_ICR bit definitions
81 **********************************************************************/
82 #define MLCICR_WPROT			(1 << 3)
83 #define MLCICR_LARGEBLOCK		(1 << 2)
84 #define MLCICR_LONGADDR			(1 << 1)
85 #define MLCICR_16BIT			(1 << 0)  /* unsupported by LPC32x0! */
86 
87 /**********************************************************************
88 * MLC_TIME_REG bit definitions
89 **********************************************************************/
90 #define MLCTIMEREG_TCEA_DELAY(n)	(((n) & 0x03) << 24)
91 #define MLCTIMEREG_BUSY_DELAY(n)	(((n) & 0x1F) << 19)
92 #define MLCTIMEREG_NAND_TA(n)		(((n) & 0x07) << 16)
93 #define MLCTIMEREG_RD_HIGH(n)		(((n) & 0x0F) << 12)
94 #define MLCTIMEREG_RD_LOW(n)		(((n) & 0x0F) << 8)
95 #define MLCTIMEREG_WR_HIGH(n)		(((n) & 0x0F) << 4)
96 #define MLCTIMEREG_WR_LOW(n)		(((n) & 0x0F) << 0)
97 
98 /**********************************************************************
99 * MLC_IRQ_MR and MLC_IRQ_SR bit definitions
100 **********************************************************************/
101 #define MLCIRQ_NAND_READY		(1 << 5)
102 #define MLCIRQ_CONTROLLER_READY		(1 << 4)
103 #define MLCIRQ_DECODE_FAILURE		(1 << 3)
104 #define MLCIRQ_DECODE_ERROR		(1 << 2)
105 #define MLCIRQ_ECC_READY		(1 << 1)
106 #define MLCIRQ_WRPROT_FAULT		(1 << 0)
107 
108 /**********************************************************************
109 * MLC_LOCK_PR bit definitions
110 **********************************************************************/
111 #define MLCLOCKPR_MAGIC			0xA25E
112 
113 /**********************************************************************
114 * MLC_ISR bit definitions
115 **********************************************************************/
116 #define MLCISR_DECODER_FAILURE		(1 << 6)
117 #define MLCISR_ERRORS			((1 << 4) | (1 << 5))
118 #define MLCISR_ERRORS_DETECTED		(1 << 3)
119 #define MLCISR_ECC_READY		(1 << 2)
120 #define MLCISR_CONTROLLER_READY		(1 << 1)
121 #define MLCISR_NAND_READY		(1 << 0)
122 
123 /**********************************************************************
124 * MLC_CEH bit definitions
125 **********************************************************************/
126 #define MLCCEH_NORMAL			(1 << 0)
127 
128 struct lpc32xx_nand_cfg_mlc {
129 	uint32_t tcea_delay;
130 	uint32_t busy_delay;
131 	uint32_t nand_ta;
132 	uint32_t rd_high;
133 	uint32_t rd_low;
134 	uint32_t wr_high;
135 	uint32_t wr_low;
136 	int wp_gpio;
137 	struct mtd_partition *parts;
138 	unsigned num_parts;
139 };
140 
141 static int lpc32xx_ooblayout_ecc(struct mtd_info *mtd, int section,
142 				 struct mtd_oob_region *oobregion)
143 {
144 	struct nand_chip *nand_chip = mtd_to_nand(mtd);
145 
146 	if (section >= nand_chip->ecc.steps)
147 		return -ERANGE;
148 
149 	oobregion->offset = ((section + 1) * 16) - nand_chip->ecc.bytes;
150 	oobregion->length = nand_chip->ecc.bytes;
151 
152 	return 0;
153 }
154 
155 static int lpc32xx_ooblayout_free(struct mtd_info *mtd, int section,
156 				  struct mtd_oob_region *oobregion)
157 {
158 	struct nand_chip *nand_chip = mtd_to_nand(mtd);
159 
160 	if (section >= nand_chip->ecc.steps)
161 		return -ERANGE;
162 
163 	oobregion->offset = 16 * section;
164 	oobregion->length = 16 - nand_chip->ecc.bytes;
165 
166 	return 0;
167 }
168 
169 static const struct mtd_ooblayout_ops lpc32xx_ooblayout_ops = {
170 	.ecc = lpc32xx_ooblayout_ecc,
171 	.free = lpc32xx_ooblayout_free,
172 };
173 
174 static struct nand_bbt_descr lpc32xx_nand_bbt = {
175 	.options = NAND_BBT_ABSPAGE | NAND_BBT_2BIT | NAND_BBT_NO_OOB |
176 		   NAND_BBT_WRITE,
177 	.pages = { 524224, 0, 0, 0, 0, 0, 0, 0 },
178 };
179 
180 static struct nand_bbt_descr lpc32xx_nand_bbt_mirror = {
181 	.options = NAND_BBT_ABSPAGE | NAND_BBT_2BIT | NAND_BBT_NO_OOB |
182 		   NAND_BBT_WRITE,
183 	.pages = { 524160, 0, 0, 0, 0, 0, 0, 0 },
184 };
185 
186 struct lpc32xx_nand_host {
187 	struct platform_device	*pdev;
188 	struct nand_chip	nand_chip;
189 	struct lpc32xx_mlc_platform_data *pdata;
190 	struct clk		*clk;
191 	void __iomem		*io_base;
192 	int			irq;
193 	struct lpc32xx_nand_cfg_mlc	*ncfg;
194 	struct completion       comp_nand;
195 	struct completion       comp_controller;
196 	uint32_t llptr;
197 	/*
198 	 * Physical addresses of ECC buffer, DMA data buffers, OOB data buffer
199 	 */
200 	dma_addr_t		oob_buf_phy;
201 	/*
202 	 * Virtual addresses of ECC buffer, DMA data buffers, OOB data buffer
203 	 */
204 	uint8_t			*oob_buf;
205 	/* Physical address of DMA base address */
206 	dma_addr_t		io_base_phy;
207 
208 	struct completion	comp_dma;
209 	struct dma_chan		*dma_chan;
210 	struct dma_slave_config	dma_slave_config;
211 	struct scatterlist	sgl;
212 	uint8_t			*dma_buf;
213 	uint8_t			*dummy_buf;
214 	int			mlcsubpages; /* number of 512bytes-subpages */
215 };
216 
217 /*
218  * Activate/Deactivate DMA Operation:
219  *
220  * Using the PL080 DMA Controller for transferring the 512 byte subpages
221  * instead of doing readl() / writel() in a loop slows it down significantly.
222  * Measurements via getnstimeofday() upon 512 byte subpage reads reveal:
223  *
224  * - readl() of 128 x 32 bits in a loop: ~20us
225  * - DMA read of 512 bytes (32 bit, 4...128 words bursts): ~60us
226  * - DMA read of 512 bytes (32 bit, no bursts): ~100us
227  *
228  * This applies to the transfer itself. In the DMA case: only the
229  * wait_for_completion() (DMA setup _not_ included).
230  *
231  * Note that the 512 bytes subpage transfer is done directly from/to a
232  * FIFO/buffer inside the NAND controller. Most of the time (~400-800us for a
233  * 2048 bytes page) is spent waiting for the NAND IRQ, anyway. (The NAND
234  * controller transferring data between its internal buffer to/from the NAND
235  * chip.)
236  *
237  * Therefore, using the PL080 DMA is disabled by default, for now.
238  *
239  */
240 static int use_dma;
241 
242 static void lpc32xx_nand_setup(struct lpc32xx_nand_host *host)
243 {
244 	uint32_t clkrate, tmp;
245 
246 	/* Reset MLC controller */
247 	writel(MLCCMD_RESET, MLC_CMD(host->io_base));
248 	udelay(1000);
249 
250 	/* Get base clock for MLC block */
251 	clkrate = clk_get_rate(host->clk);
252 	if (clkrate == 0)
253 		clkrate = 104000000;
254 
255 	/* Unlock MLC_ICR
256 	 * (among others, will be locked again automatically) */
257 	writew(MLCLOCKPR_MAGIC, MLC_LOCK_PR(host->io_base));
258 
259 	/* Configure MLC Controller: Large Block, 5 Byte Address */
260 	tmp = MLCICR_LARGEBLOCK | MLCICR_LONGADDR;
261 	writel(tmp, MLC_ICR(host->io_base));
262 
263 	/* Unlock MLC_TIME_REG
264 	 * (among others, will be locked again automatically) */
265 	writew(MLCLOCKPR_MAGIC, MLC_LOCK_PR(host->io_base));
266 
267 	/* Compute clock setup values, see LPC and NAND manual */
268 	tmp = 0;
269 	tmp |= MLCTIMEREG_TCEA_DELAY(clkrate / host->ncfg->tcea_delay + 1);
270 	tmp |= MLCTIMEREG_BUSY_DELAY(clkrate / host->ncfg->busy_delay + 1);
271 	tmp |= MLCTIMEREG_NAND_TA(clkrate / host->ncfg->nand_ta + 1);
272 	tmp |= MLCTIMEREG_RD_HIGH(clkrate / host->ncfg->rd_high + 1);
273 	tmp |= MLCTIMEREG_RD_LOW(clkrate / host->ncfg->rd_low);
274 	tmp |= MLCTIMEREG_WR_HIGH(clkrate / host->ncfg->wr_high + 1);
275 	tmp |= MLCTIMEREG_WR_LOW(clkrate / host->ncfg->wr_low);
276 	writel(tmp, MLC_TIME_REG(host->io_base));
277 
278 	/* Enable IRQ for CONTROLLER_READY and NAND_READY */
279 	writeb(MLCIRQ_CONTROLLER_READY | MLCIRQ_NAND_READY,
280 			MLC_IRQ_MR(host->io_base));
281 
282 	/* Normal nCE operation: nCE controlled by controller */
283 	writel(MLCCEH_NORMAL, MLC_CEH(host->io_base));
284 }
285 
286 /*
287  * Hardware specific access to control lines
288  */
289 static void lpc32xx_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
290 				  unsigned int ctrl)
291 {
292 	struct nand_chip *nand_chip = mtd_to_nand(mtd);
293 	struct lpc32xx_nand_host *host = nand_get_controller_data(nand_chip);
294 
295 	if (cmd != NAND_CMD_NONE) {
296 		if (ctrl & NAND_CLE)
297 			writel(cmd, MLC_CMD(host->io_base));
298 		else
299 			writel(cmd, MLC_ADDR(host->io_base));
300 	}
301 }
302 
303 /*
304  * Read Device Ready (NAND device _and_ controller ready)
305  */
306 static int lpc32xx_nand_device_ready(struct mtd_info *mtd)
307 {
308 	struct nand_chip *nand_chip = mtd_to_nand(mtd);
309 	struct lpc32xx_nand_host *host = nand_get_controller_data(nand_chip);
310 
311 	if ((readb(MLC_ISR(host->io_base)) &
312 	     (MLCISR_CONTROLLER_READY | MLCISR_NAND_READY)) ==
313 	    (MLCISR_CONTROLLER_READY | MLCISR_NAND_READY))
314 		return  1;
315 
316 	return 0;
317 }
318 
319 static irqreturn_t lpc3xxx_nand_irq(int irq, struct lpc32xx_nand_host *host)
320 {
321 	uint8_t sr;
322 
323 	/* Clear interrupt flag by reading status */
324 	sr = readb(MLC_IRQ_SR(host->io_base));
325 	if (sr & MLCIRQ_NAND_READY)
326 		complete(&host->comp_nand);
327 	if (sr & MLCIRQ_CONTROLLER_READY)
328 		complete(&host->comp_controller);
329 
330 	return IRQ_HANDLED;
331 }
332 
333 static int lpc32xx_waitfunc_nand(struct mtd_info *mtd, struct nand_chip *chip)
334 {
335 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
336 
337 	if (readb(MLC_ISR(host->io_base)) & MLCISR_NAND_READY)
338 		goto exit;
339 
340 	wait_for_completion(&host->comp_nand);
341 
342 	while (!(readb(MLC_ISR(host->io_base)) & MLCISR_NAND_READY)) {
343 		/* Seems to be delayed sometimes by controller */
344 		dev_dbg(&mtd->dev, "Warning: NAND not ready.\n");
345 		cpu_relax();
346 	}
347 
348 exit:
349 	return NAND_STATUS_READY;
350 }
351 
352 static int lpc32xx_waitfunc_controller(struct mtd_info *mtd,
353 				       struct nand_chip *chip)
354 {
355 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
356 
357 	if (readb(MLC_ISR(host->io_base)) & MLCISR_CONTROLLER_READY)
358 		goto exit;
359 
360 	wait_for_completion(&host->comp_controller);
361 
362 	while (!(readb(MLC_ISR(host->io_base)) &
363 		 MLCISR_CONTROLLER_READY)) {
364 		dev_dbg(&mtd->dev, "Warning: Controller not ready.\n");
365 		cpu_relax();
366 	}
367 
368 exit:
369 	return NAND_STATUS_READY;
370 }
371 
372 static int lpc32xx_waitfunc(struct mtd_info *mtd, struct nand_chip *chip)
373 {
374 	lpc32xx_waitfunc_nand(mtd, chip);
375 	lpc32xx_waitfunc_controller(mtd, chip);
376 
377 	return NAND_STATUS_READY;
378 }
379 
380 /*
381  * Enable NAND write protect
382  */
383 static void lpc32xx_wp_enable(struct lpc32xx_nand_host *host)
384 {
385 	if (gpio_is_valid(host->ncfg->wp_gpio))
386 		gpio_set_value(host->ncfg->wp_gpio, 0);
387 }
388 
389 /*
390  * Disable NAND write protect
391  */
392 static void lpc32xx_wp_disable(struct lpc32xx_nand_host *host)
393 {
394 	if (gpio_is_valid(host->ncfg->wp_gpio))
395 		gpio_set_value(host->ncfg->wp_gpio, 1);
396 }
397 
398 static void lpc32xx_dma_complete_func(void *completion)
399 {
400 	complete(completion);
401 }
402 
403 static int lpc32xx_xmit_dma(struct mtd_info *mtd, void *mem, int len,
404 			    enum dma_transfer_direction dir)
405 {
406 	struct nand_chip *chip = mtd_to_nand(mtd);
407 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
408 	struct dma_async_tx_descriptor *desc;
409 	int flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
410 	int res;
411 
412 	sg_init_one(&host->sgl, mem, len);
413 
414 	res = dma_map_sg(host->dma_chan->device->dev, &host->sgl, 1,
415 			 DMA_BIDIRECTIONAL);
416 	if (res != 1) {
417 		dev_err(mtd->dev.parent, "Failed to map sg list\n");
418 		return -ENXIO;
419 	}
420 	desc = dmaengine_prep_slave_sg(host->dma_chan, &host->sgl, 1, dir,
421 				       flags);
422 	if (!desc) {
423 		dev_err(mtd->dev.parent, "Failed to prepare slave sg\n");
424 		goto out1;
425 	}
426 
427 	init_completion(&host->comp_dma);
428 	desc->callback = lpc32xx_dma_complete_func;
429 	desc->callback_param = &host->comp_dma;
430 
431 	dmaengine_submit(desc);
432 	dma_async_issue_pending(host->dma_chan);
433 
434 	wait_for_completion_timeout(&host->comp_dma, msecs_to_jiffies(1000));
435 
436 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
437 		     DMA_BIDIRECTIONAL);
438 	return 0;
439 out1:
440 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
441 		     DMA_BIDIRECTIONAL);
442 	return -ENXIO;
443 }
444 
445 static int lpc32xx_read_page(struct mtd_info *mtd, struct nand_chip *chip,
446 			     uint8_t *buf, int oob_required, int page)
447 {
448 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
449 	int i, j;
450 	uint8_t *oobbuf = chip->oob_poi;
451 	uint32_t mlc_isr;
452 	int res;
453 	uint8_t *dma_buf;
454 	bool dma_mapped;
455 
456 	if ((void *)buf <= high_memory) {
457 		dma_buf = buf;
458 		dma_mapped = true;
459 	} else {
460 		dma_buf = host->dma_buf;
461 		dma_mapped = false;
462 	}
463 
464 	/* Writing Command and Address */
465 	nand_read_page_op(chip, page, 0, NULL, 0);
466 
467 	/* For all sub-pages */
468 	for (i = 0; i < host->mlcsubpages; i++) {
469 		/* Start Auto Decode Command */
470 		writeb(0x00, MLC_ECC_AUTO_DEC_REG(host->io_base));
471 
472 		/* Wait for Controller Ready */
473 		lpc32xx_waitfunc_controller(mtd, chip);
474 
475 		/* Check ECC Error status */
476 		mlc_isr = readl(MLC_ISR(host->io_base));
477 		if (mlc_isr & MLCISR_DECODER_FAILURE) {
478 			mtd->ecc_stats.failed++;
479 			dev_warn(&mtd->dev, "%s: DECODER_FAILURE\n", __func__);
480 		} else if (mlc_isr & MLCISR_ERRORS_DETECTED) {
481 			mtd->ecc_stats.corrected += ((mlc_isr >> 4) & 0x3) + 1;
482 		}
483 
484 		/* Read 512 + 16 Bytes */
485 		if (use_dma) {
486 			res = lpc32xx_xmit_dma(mtd, dma_buf + i * 512, 512,
487 					       DMA_DEV_TO_MEM);
488 			if (res)
489 				return res;
490 		} else {
491 			for (j = 0; j < (512 >> 2); j++) {
492 				*((uint32_t *)(buf)) =
493 					readl(MLC_BUFF(host->io_base));
494 				buf += 4;
495 			}
496 		}
497 		for (j = 0; j < (16 >> 2); j++) {
498 			*((uint32_t *)(oobbuf)) =
499 				readl(MLC_BUFF(host->io_base));
500 			oobbuf += 4;
501 		}
502 	}
503 
504 	if (use_dma && !dma_mapped)
505 		memcpy(buf, dma_buf, mtd->writesize);
506 
507 	return 0;
508 }
509 
510 static int lpc32xx_write_page_lowlevel(struct mtd_info *mtd,
511 				       struct nand_chip *chip,
512 				       const uint8_t *buf, int oob_required,
513 				       int page)
514 {
515 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
516 	const uint8_t *oobbuf = chip->oob_poi;
517 	uint8_t *dma_buf = (uint8_t *)buf;
518 	int res;
519 	int i, j;
520 
521 	if (use_dma && (void *)buf >= high_memory) {
522 		dma_buf = host->dma_buf;
523 		memcpy(dma_buf, buf, mtd->writesize);
524 	}
525 
526 	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
527 
528 	for (i = 0; i < host->mlcsubpages; i++) {
529 		/* Start Encode */
530 		writeb(0x00, MLC_ECC_ENC_REG(host->io_base));
531 
532 		/* Write 512 + 6 Bytes to Buffer */
533 		if (use_dma) {
534 			res = lpc32xx_xmit_dma(mtd, dma_buf + i * 512, 512,
535 					       DMA_MEM_TO_DEV);
536 			if (res)
537 				return res;
538 		} else {
539 			for (j = 0; j < (512 >> 2); j++) {
540 				writel(*((uint32_t *)(buf)),
541 				       MLC_BUFF(host->io_base));
542 				buf += 4;
543 			}
544 		}
545 		writel(*((uint32_t *)(oobbuf)), MLC_BUFF(host->io_base));
546 		oobbuf += 4;
547 		writew(*((uint16_t *)(oobbuf)), MLC_BUFF(host->io_base));
548 		oobbuf += 12;
549 
550 		/* Auto Encode w/ Bit 8 = 0 (see LPC MLC Controller manual) */
551 		writeb(0x00, MLC_ECC_AUTO_ENC_REG(host->io_base));
552 
553 		/* Wait for Controller Ready */
554 		lpc32xx_waitfunc_controller(mtd, chip);
555 	}
556 
557 	return nand_prog_page_end_op(chip);
558 }
559 
560 static int lpc32xx_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
561 			    int page)
562 {
563 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
564 
565 	/* Read whole page - necessary with MLC controller! */
566 	lpc32xx_read_page(mtd, chip, host->dummy_buf, 1, page);
567 
568 	return 0;
569 }
570 
571 static int lpc32xx_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
572 			      int page)
573 {
574 	/* None, write_oob conflicts with the automatic LPC MLC ECC decoder! */
575 	return 0;
576 }
577 
578 /* Prepares MLC for transfers with H/W ECC enabled: always enabled anyway */
579 static void lpc32xx_ecc_enable(struct mtd_info *mtd, int mode)
580 {
581 	/* Always enabled! */
582 }
583 
584 static int lpc32xx_dma_setup(struct lpc32xx_nand_host *host)
585 {
586 	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
587 	dma_cap_mask_t mask;
588 
589 	if (!host->pdata || !host->pdata->dma_filter) {
590 		dev_err(mtd->dev.parent, "no DMA platform data\n");
591 		return -ENOENT;
592 	}
593 
594 	dma_cap_zero(mask);
595 	dma_cap_set(DMA_SLAVE, mask);
596 	host->dma_chan = dma_request_channel(mask, host->pdata->dma_filter,
597 					     "nand-mlc");
598 	if (!host->dma_chan) {
599 		dev_err(mtd->dev.parent, "Failed to request DMA channel\n");
600 		return -EBUSY;
601 	}
602 
603 	/*
604 	 * Set direction to a sensible value even if the dmaengine driver
605 	 * should ignore it. With the default (DMA_MEM_TO_MEM), the amba-pl08x
606 	 * driver criticizes it as "alien transfer direction".
607 	 */
608 	host->dma_slave_config.direction = DMA_DEV_TO_MEM;
609 	host->dma_slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
610 	host->dma_slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
611 	host->dma_slave_config.src_maxburst = 128;
612 	host->dma_slave_config.dst_maxburst = 128;
613 	/* DMA controller does flow control: */
614 	host->dma_slave_config.device_fc = false;
615 	host->dma_slave_config.src_addr = MLC_BUFF(host->io_base_phy);
616 	host->dma_slave_config.dst_addr = MLC_BUFF(host->io_base_phy);
617 	if (dmaengine_slave_config(host->dma_chan, &host->dma_slave_config)) {
618 		dev_err(mtd->dev.parent, "Failed to setup DMA slave\n");
619 		goto out1;
620 	}
621 
622 	return 0;
623 out1:
624 	dma_release_channel(host->dma_chan);
625 	return -ENXIO;
626 }
627 
628 static struct lpc32xx_nand_cfg_mlc *lpc32xx_parse_dt(struct device *dev)
629 {
630 	struct lpc32xx_nand_cfg_mlc *ncfg;
631 	struct device_node *np = dev->of_node;
632 
633 	ncfg = devm_kzalloc(dev, sizeof(*ncfg), GFP_KERNEL);
634 	if (!ncfg)
635 		return NULL;
636 
637 	of_property_read_u32(np, "nxp,tcea-delay", &ncfg->tcea_delay);
638 	of_property_read_u32(np, "nxp,busy-delay", &ncfg->busy_delay);
639 	of_property_read_u32(np, "nxp,nand-ta", &ncfg->nand_ta);
640 	of_property_read_u32(np, "nxp,rd-high", &ncfg->rd_high);
641 	of_property_read_u32(np, "nxp,rd-low", &ncfg->rd_low);
642 	of_property_read_u32(np, "nxp,wr-high", &ncfg->wr_high);
643 	of_property_read_u32(np, "nxp,wr-low", &ncfg->wr_low);
644 
645 	if (!ncfg->tcea_delay || !ncfg->busy_delay || !ncfg->nand_ta ||
646 	    !ncfg->rd_high || !ncfg->rd_low || !ncfg->wr_high ||
647 	    !ncfg->wr_low) {
648 		dev_err(dev, "chip parameters not specified correctly\n");
649 		return NULL;
650 	}
651 
652 	ncfg->wp_gpio = of_get_named_gpio(np, "gpios", 0);
653 
654 	return ncfg;
655 }
656 
657 static int lpc32xx_nand_attach_chip(struct nand_chip *chip)
658 {
659 	struct mtd_info *mtd = nand_to_mtd(chip);
660 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
661 	struct device *dev = &host->pdev->dev;
662 
663 	host->dma_buf = devm_kzalloc(dev, mtd->writesize, GFP_KERNEL);
664 	if (!host->dma_buf)
665 		return -ENOMEM;
666 
667 	host->dummy_buf = devm_kzalloc(dev, mtd->writesize, GFP_KERNEL);
668 	if (!host->dummy_buf)
669 		return -ENOMEM;
670 
671 	chip->ecc.mode = NAND_ECC_HW;
672 	chip->ecc.size = 512;
673 	mtd_set_ooblayout(mtd, &lpc32xx_ooblayout_ops);
674 	host->mlcsubpages = mtd->writesize / 512;
675 
676 	return 0;
677 }
678 
679 static const struct nand_controller_ops lpc32xx_nand_controller_ops = {
680 	.attach_chip = lpc32xx_nand_attach_chip,
681 };
682 
683 /*
684  * Probe for NAND controller
685  */
686 static int lpc32xx_nand_probe(struct platform_device *pdev)
687 {
688 	struct lpc32xx_nand_host *host;
689 	struct mtd_info *mtd;
690 	struct nand_chip *nand_chip;
691 	struct resource *rc;
692 	int res;
693 
694 	/* Allocate memory for the device structure (and zero it) */
695 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
696 	if (!host)
697 		return -ENOMEM;
698 
699 	host->pdev = pdev;
700 
701 	rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
702 	host->io_base = devm_ioremap_resource(&pdev->dev, rc);
703 	if (IS_ERR(host->io_base))
704 		return PTR_ERR(host->io_base);
705 
706 	host->io_base_phy = rc->start;
707 
708 	nand_chip = &host->nand_chip;
709 	mtd = nand_to_mtd(nand_chip);
710 	if (pdev->dev.of_node)
711 		host->ncfg = lpc32xx_parse_dt(&pdev->dev);
712 	if (!host->ncfg) {
713 		dev_err(&pdev->dev,
714 			"Missing or bad NAND config from device tree\n");
715 		return -ENOENT;
716 	}
717 	if (host->ncfg->wp_gpio == -EPROBE_DEFER)
718 		return -EPROBE_DEFER;
719 	if (gpio_is_valid(host->ncfg->wp_gpio) &&
720 			gpio_request(host->ncfg->wp_gpio, "NAND WP")) {
721 		dev_err(&pdev->dev, "GPIO not available\n");
722 		return -EBUSY;
723 	}
724 	lpc32xx_wp_disable(host);
725 
726 	host->pdata = dev_get_platdata(&pdev->dev);
727 
728 	/* link the private data structures */
729 	nand_set_controller_data(nand_chip, host);
730 	nand_set_flash_node(nand_chip, pdev->dev.of_node);
731 	mtd->dev.parent = &pdev->dev;
732 
733 	/* Get NAND clock */
734 	host->clk = clk_get(&pdev->dev, NULL);
735 	if (IS_ERR(host->clk)) {
736 		dev_err(&pdev->dev, "Clock initialization failure\n");
737 		res = -ENOENT;
738 		goto free_gpio;
739 	}
740 	res = clk_prepare_enable(host->clk);
741 	if (res)
742 		goto put_clk;
743 
744 	nand_chip->cmd_ctrl = lpc32xx_nand_cmd_ctrl;
745 	nand_chip->dev_ready = lpc32xx_nand_device_ready;
746 	nand_chip->chip_delay = 25; /* us */
747 	nand_chip->IO_ADDR_R = MLC_DATA(host->io_base);
748 	nand_chip->IO_ADDR_W = MLC_DATA(host->io_base);
749 
750 	/* Init NAND controller */
751 	lpc32xx_nand_setup(host);
752 
753 	platform_set_drvdata(pdev, host);
754 
755 	/* Initialize function pointers */
756 	nand_chip->ecc.hwctl = lpc32xx_ecc_enable;
757 	nand_chip->ecc.read_page_raw = lpc32xx_read_page;
758 	nand_chip->ecc.read_page = lpc32xx_read_page;
759 	nand_chip->ecc.write_page_raw = lpc32xx_write_page_lowlevel;
760 	nand_chip->ecc.write_page = lpc32xx_write_page_lowlevel;
761 	nand_chip->ecc.write_oob = lpc32xx_write_oob;
762 	nand_chip->ecc.read_oob = lpc32xx_read_oob;
763 	nand_chip->ecc.strength = 4;
764 	nand_chip->ecc.bytes = 10;
765 	nand_chip->waitfunc = lpc32xx_waitfunc;
766 
767 	nand_chip->options = NAND_NO_SUBPAGE_WRITE;
768 	nand_chip->bbt_options = NAND_BBT_USE_FLASH | NAND_BBT_NO_OOB;
769 	nand_chip->bbt_td = &lpc32xx_nand_bbt;
770 	nand_chip->bbt_md = &lpc32xx_nand_bbt_mirror;
771 
772 	if (use_dma) {
773 		res = lpc32xx_dma_setup(host);
774 		if (res) {
775 			res = -EIO;
776 			goto unprepare_clk;
777 		}
778 	}
779 
780 	/* initially clear interrupt status */
781 	readb(MLC_IRQ_SR(host->io_base));
782 
783 	init_completion(&host->comp_nand);
784 	init_completion(&host->comp_controller);
785 
786 	host->irq = platform_get_irq(pdev, 0);
787 	if (host->irq < 0) {
788 		dev_err(&pdev->dev, "failed to get platform irq\n");
789 		res = -EINVAL;
790 		goto release_dma_chan;
791 	}
792 
793 	if (request_irq(host->irq, (irq_handler_t)&lpc3xxx_nand_irq,
794 			IRQF_TRIGGER_HIGH, DRV_NAME, host)) {
795 		dev_err(&pdev->dev, "Error requesting NAND IRQ\n");
796 		res = -ENXIO;
797 		goto release_dma_chan;
798 	}
799 
800 	/*
801 	 * Scan to find existence of the device and get the type of NAND device:
802 	 * SMALL block or LARGE block.
803 	 */
804 	nand_chip->dummy_controller.ops = &lpc32xx_nand_controller_ops;
805 	res = nand_scan(mtd, 1);
806 	if (res)
807 		goto free_irq;
808 
809 	mtd->name = DRV_NAME;
810 
811 	res = mtd_device_register(mtd, host->ncfg->parts,
812 				  host->ncfg->num_parts);
813 	if (res)
814 		goto cleanup_nand;
815 
816 	return 0;
817 
818 cleanup_nand:
819 	nand_cleanup(nand_chip);
820 free_irq:
821 	free_irq(host->irq, host);
822 release_dma_chan:
823 	if (use_dma)
824 		dma_release_channel(host->dma_chan);
825 unprepare_clk:
826 	clk_disable_unprepare(host->clk);
827 put_clk:
828 	clk_put(host->clk);
829 free_gpio:
830 	lpc32xx_wp_enable(host);
831 	gpio_free(host->ncfg->wp_gpio);
832 
833 	return res;
834 }
835 
836 /*
837  * Remove NAND device
838  */
839 static int lpc32xx_nand_remove(struct platform_device *pdev)
840 {
841 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
842 	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
843 
844 	nand_release(mtd);
845 	free_irq(host->irq, host);
846 	if (use_dma)
847 		dma_release_channel(host->dma_chan);
848 
849 	clk_disable_unprepare(host->clk);
850 	clk_put(host->clk);
851 
852 	lpc32xx_wp_enable(host);
853 	gpio_free(host->ncfg->wp_gpio);
854 
855 	return 0;
856 }
857 
858 #ifdef CONFIG_PM
859 static int lpc32xx_nand_resume(struct platform_device *pdev)
860 {
861 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
862 	int ret;
863 
864 	/* Re-enable NAND clock */
865 	ret = clk_prepare_enable(host->clk);
866 	if (ret)
867 		return ret;
868 
869 	/* Fresh init of NAND controller */
870 	lpc32xx_nand_setup(host);
871 
872 	/* Disable write protect */
873 	lpc32xx_wp_disable(host);
874 
875 	return 0;
876 }
877 
878 static int lpc32xx_nand_suspend(struct platform_device *pdev, pm_message_t pm)
879 {
880 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
881 
882 	/* Enable write protect for safety */
883 	lpc32xx_wp_enable(host);
884 
885 	/* Disable clock */
886 	clk_disable_unprepare(host->clk);
887 	return 0;
888 }
889 
890 #else
891 #define lpc32xx_nand_resume NULL
892 #define lpc32xx_nand_suspend NULL
893 #endif
894 
895 static const struct of_device_id lpc32xx_nand_match[] = {
896 	{ .compatible = "nxp,lpc3220-mlc" },
897 	{ /* sentinel */ },
898 };
899 MODULE_DEVICE_TABLE(of, lpc32xx_nand_match);
900 
901 static struct platform_driver lpc32xx_nand_driver = {
902 	.probe		= lpc32xx_nand_probe,
903 	.remove		= lpc32xx_nand_remove,
904 	.resume		= lpc32xx_nand_resume,
905 	.suspend	= lpc32xx_nand_suspend,
906 	.driver		= {
907 		.name	= DRV_NAME,
908 		.of_match_table = lpc32xx_nand_match,
909 	},
910 };
911 
912 module_platform_driver(lpc32xx_nand_driver);
913 
914 MODULE_LICENSE("GPL");
915 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
916 MODULE_DESCRIPTION("NAND driver for the NXP LPC32XX MLC controller");
917