xref: /openbmc/linux/drivers/mtd/nand/raw/lpc32xx_mlc.c (revision c4e78957)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Driver for NAND MLC Controller in LPC32xx
4  *
5  * Author: Roland Stigge <stigge@antcom.de>
6  *
7  * Copyright © 2011 WORK Microwave GmbH
8  * Copyright © 2011, 2012 Roland Stigge
9  *
10  * NAND Flash Controller Operation:
11  * - Read: Auto Decode
12  * - Write: Auto Encode
13  * - Tested Page Sizes: 2048, 4096
14  */
15 
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/mtd/mtd.h>
20 #include <linux/mtd/rawnand.h>
21 #include <linux/mtd/partitions.h>
22 #include <linux/clk.h>
23 #include <linux/err.h>
24 #include <linux/delay.h>
25 #include <linux/completion.h>
26 #include <linux/interrupt.h>
27 #include <linux/of.h>
28 #include <linux/of_gpio.h>
29 #include <linux/mtd/lpc32xx_mlc.h>
30 #include <linux/io.h>
31 #include <linux/mm.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/dmaengine.h>
34 
35 #define DRV_NAME "lpc32xx_mlc"
36 
37 /**********************************************************************
38 * MLC NAND controller register offsets
39 **********************************************************************/
40 
41 #define MLC_BUFF(x)			(x + 0x00000)
42 #define MLC_DATA(x)			(x + 0x08000)
43 #define MLC_CMD(x)			(x + 0x10000)
44 #define MLC_ADDR(x)			(x + 0x10004)
45 #define MLC_ECC_ENC_REG(x)		(x + 0x10008)
46 #define MLC_ECC_DEC_REG(x)		(x + 0x1000C)
47 #define MLC_ECC_AUTO_ENC_REG(x)		(x + 0x10010)
48 #define MLC_ECC_AUTO_DEC_REG(x)		(x + 0x10014)
49 #define MLC_RPR(x)			(x + 0x10018)
50 #define MLC_WPR(x)			(x + 0x1001C)
51 #define MLC_RUBP(x)			(x + 0x10020)
52 #define MLC_ROBP(x)			(x + 0x10024)
53 #define MLC_SW_WP_ADD_LOW(x)		(x + 0x10028)
54 #define MLC_SW_WP_ADD_HIG(x)		(x + 0x1002C)
55 #define MLC_ICR(x)			(x + 0x10030)
56 #define MLC_TIME_REG(x)			(x + 0x10034)
57 #define MLC_IRQ_MR(x)			(x + 0x10038)
58 #define MLC_IRQ_SR(x)			(x + 0x1003C)
59 #define MLC_LOCK_PR(x)			(x + 0x10044)
60 #define MLC_ISR(x)			(x + 0x10048)
61 #define MLC_CEH(x)			(x + 0x1004C)
62 
63 /**********************************************************************
64 * MLC_CMD bit definitions
65 **********************************************************************/
66 #define MLCCMD_RESET			0xFF
67 
68 /**********************************************************************
69 * MLC_ICR bit definitions
70 **********************************************************************/
71 #define MLCICR_WPROT			(1 << 3)
72 #define MLCICR_LARGEBLOCK		(1 << 2)
73 #define MLCICR_LONGADDR			(1 << 1)
74 #define MLCICR_16BIT			(1 << 0)  /* unsupported by LPC32x0! */
75 
76 /**********************************************************************
77 * MLC_TIME_REG bit definitions
78 **********************************************************************/
79 #define MLCTIMEREG_TCEA_DELAY(n)	(((n) & 0x03) << 24)
80 #define MLCTIMEREG_BUSY_DELAY(n)	(((n) & 0x1F) << 19)
81 #define MLCTIMEREG_NAND_TA(n)		(((n) & 0x07) << 16)
82 #define MLCTIMEREG_RD_HIGH(n)		(((n) & 0x0F) << 12)
83 #define MLCTIMEREG_RD_LOW(n)		(((n) & 0x0F) << 8)
84 #define MLCTIMEREG_WR_HIGH(n)		(((n) & 0x0F) << 4)
85 #define MLCTIMEREG_WR_LOW(n)		(((n) & 0x0F) << 0)
86 
87 /**********************************************************************
88 * MLC_IRQ_MR and MLC_IRQ_SR bit definitions
89 **********************************************************************/
90 #define MLCIRQ_NAND_READY		(1 << 5)
91 #define MLCIRQ_CONTROLLER_READY		(1 << 4)
92 #define MLCIRQ_DECODE_FAILURE		(1 << 3)
93 #define MLCIRQ_DECODE_ERROR		(1 << 2)
94 #define MLCIRQ_ECC_READY		(1 << 1)
95 #define MLCIRQ_WRPROT_FAULT		(1 << 0)
96 
97 /**********************************************************************
98 * MLC_LOCK_PR bit definitions
99 **********************************************************************/
100 #define MLCLOCKPR_MAGIC			0xA25E
101 
102 /**********************************************************************
103 * MLC_ISR bit definitions
104 **********************************************************************/
105 #define MLCISR_DECODER_FAILURE		(1 << 6)
106 #define MLCISR_ERRORS			((1 << 4) | (1 << 5))
107 #define MLCISR_ERRORS_DETECTED		(1 << 3)
108 #define MLCISR_ECC_READY		(1 << 2)
109 #define MLCISR_CONTROLLER_READY		(1 << 1)
110 #define MLCISR_NAND_READY		(1 << 0)
111 
112 /**********************************************************************
113 * MLC_CEH bit definitions
114 **********************************************************************/
115 #define MLCCEH_NORMAL			(1 << 0)
116 
117 struct lpc32xx_nand_cfg_mlc {
118 	uint32_t tcea_delay;
119 	uint32_t busy_delay;
120 	uint32_t nand_ta;
121 	uint32_t rd_high;
122 	uint32_t rd_low;
123 	uint32_t wr_high;
124 	uint32_t wr_low;
125 	int wp_gpio;
126 	struct mtd_partition *parts;
127 	unsigned num_parts;
128 };
129 
130 static int lpc32xx_ooblayout_ecc(struct mtd_info *mtd, int section,
131 				 struct mtd_oob_region *oobregion)
132 {
133 	struct nand_chip *nand_chip = mtd_to_nand(mtd);
134 
135 	if (section >= nand_chip->ecc.steps)
136 		return -ERANGE;
137 
138 	oobregion->offset = ((section + 1) * 16) - nand_chip->ecc.bytes;
139 	oobregion->length = nand_chip->ecc.bytes;
140 
141 	return 0;
142 }
143 
144 static int lpc32xx_ooblayout_free(struct mtd_info *mtd, int section,
145 				  struct mtd_oob_region *oobregion)
146 {
147 	struct nand_chip *nand_chip = mtd_to_nand(mtd);
148 
149 	if (section >= nand_chip->ecc.steps)
150 		return -ERANGE;
151 
152 	oobregion->offset = 16 * section;
153 	oobregion->length = 16 - nand_chip->ecc.bytes;
154 
155 	return 0;
156 }
157 
158 static const struct mtd_ooblayout_ops lpc32xx_ooblayout_ops = {
159 	.ecc = lpc32xx_ooblayout_ecc,
160 	.free = lpc32xx_ooblayout_free,
161 };
162 
163 static struct nand_bbt_descr lpc32xx_nand_bbt = {
164 	.options = NAND_BBT_ABSPAGE | NAND_BBT_2BIT | NAND_BBT_NO_OOB |
165 		   NAND_BBT_WRITE,
166 	.pages = { 524224, 0, 0, 0, 0, 0, 0, 0 },
167 };
168 
169 static struct nand_bbt_descr lpc32xx_nand_bbt_mirror = {
170 	.options = NAND_BBT_ABSPAGE | NAND_BBT_2BIT | NAND_BBT_NO_OOB |
171 		   NAND_BBT_WRITE,
172 	.pages = { 524160, 0, 0, 0, 0, 0, 0, 0 },
173 };
174 
175 struct lpc32xx_nand_host {
176 	struct platform_device	*pdev;
177 	struct nand_chip	nand_chip;
178 	struct lpc32xx_mlc_platform_data *pdata;
179 	struct clk		*clk;
180 	void __iomem		*io_base;
181 	int			irq;
182 	struct lpc32xx_nand_cfg_mlc	*ncfg;
183 	struct completion       comp_nand;
184 	struct completion       comp_controller;
185 	uint32_t llptr;
186 	/*
187 	 * Physical addresses of ECC buffer, DMA data buffers, OOB data buffer
188 	 */
189 	dma_addr_t		oob_buf_phy;
190 	/*
191 	 * Virtual addresses of ECC buffer, DMA data buffers, OOB data buffer
192 	 */
193 	uint8_t			*oob_buf;
194 	/* Physical address of DMA base address */
195 	dma_addr_t		io_base_phy;
196 
197 	struct completion	comp_dma;
198 	struct dma_chan		*dma_chan;
199 	struct dma_slave_config	dma_slave_config;
200 	struct scatterlist	sgl;
201 	uint8_t			*dma_buf;
202 	uint8_t			*dummy_buf;
203 	int			mlcsubpages; /* number of 512bytes-subpages */
204 };
205 
206 /*
207  * Activate/Deactivate DMA Operation:
208  *
209  * Using the PL080 DMA Controller for transferring the 512 byte subpages
210  * instead of doing readl() / writel() in a loop slows it down significantly.
211  * Measurements via getnstimeofday() upon 512 byte subpage reads reveal:
212  *
213  * - readl() of 128 x 32 bits in a loop: ~20us
214  * - DMA read of 512 bytes (32 bit, 4...128 words bursts): ~60us
215  * - DMA read of 512 bytes (32 bit, no bursts): ~100us
216  *
217  * This applies to the transfer itself. In the DMA case: only the
218  * wait_for_completion() (DMA setup _not_ included).
219  *
220  * Note that the 512 bytes subpage transfer is done directly from/to a
221  * FIFO/buffer inside the NAND controller. Most of the time (~400-800us for a
222  * 2048 bytes page) is spent waiting for the NAND IRQ, anyway. (The NAND
223  * controller transferring data between its internal buffer to/from the NAND
224  * chip.)
225  *
226  * Therefore, using the PL080 DMA is disabled by default, for now.
227  *
228  */
229 static int use_dma;
230 
231 static void lpc32xx_nand_setup(struct lpc32xx_nand_host *host)
232 {
233 	uint32_t clkrate, tmp;
234 
235 	/* Reset MLC controller */
236 	writel(MLCCMD_RESET, MLC_CMD(host->io_base));
237 	udelay(1000);
238 
239 	/* Get base clock for MLC block */
240 	clkrate = clk_get_rate(host->clk);
241 	if (clkrate == 0)
242 		clkrate = 104000000;
243 
244 	/* Unlock MLC_ICR
245 	 * (among others, will be locked again automatically) */
246 	writew(MLCLOCKPR_MAGIC, MLC_LOCK_PR(host->io_base));
247 
248 	/* Configure MLC Controller: Large Block, 5 Byte Address */
249 	tmp = MLCICR_LARGEBLOCK | MLCICR_LONGADDR;
250 	writel(tmp, MLC_ICR(host->io_base));
251 
252 	/* Unlock MLC_TIME_REG
253 	 * (among others, will be locked again automatically) */
254 	writew(MLCLOCKPR_MAGIC, MLC_LOCK_PR(host->io_base));
255 
256 	/* Compute clock setup values, see LPC and NAND manual */
257 	tmp = 0;
258 	tmp |= MLCTIMEREG_TCEA_DELAY(clkrate / host->ncfg->tcea_delay + 1);
259 	tmp |= MLCTIMEREG_BUSY_DELAY(clkrate / host->ncfg->busy_delay + 1);
260 	tmp |= MLCTIMEREG_NAND_TA(clkrate / host->ncfg->nand_ta + 1);
261 	tmp |= MLCTIMEREG_RD_HIGH(clkrate / host->ncfg->rd_high + 1);
262 	tmp |= MLCTIMEREG_RD_LOW(clkrate / host->ncfg->rd_low);
263 	tmp |= MLCTIMEREG_WR_HIGH(clkrate / host->ncfg->wr_high + 1);
264 	tmp |= MLCTIMEREG_WR_LOW(clkrate / host->ncfg->wr_low);
265 	writel(tmp, MLC_TIME_REG(host->io_base));
266 
267 	/* Enable IRQ for CONTROLLER_READY and NAND_READY */
268 	writeb(MLCIRQ_CONTROLLER_READY | MLCIRQ_NAND_READY,
269 			MLC_IRQ_MR(host->io_base));
270 
271 	/* Normal nCE operation: nCE controlled by controller */
272 	writel(MLCCEH_NORMAL, MLC_CEH(host->io_base));
273 }
274 
275 /*
276  * Hardware specific access to control lines
277  */
278 static void lpc32xx_nand_cmd_ctrl(struct nand_chip *nand_chip, int cmd,
279 				  unsigned int ctrl)
280 {
281 	struct lpc32xx_nand_host *host = nand_get_controller_data(nand_chip);
282 
283 	if (cmd != NAND_CMD_NONE) {
284 		if (ctrl & NAND_CLE)
285 			writel(cmd, MLC_CMD(host->io_base));
286 		else
287 			writel(cmd, MLC_ADDR(host->io_base));
288 	}
289 }
290 
291 /*
292  * Read Device Ready (NAND device _and_ controller ready)
293  */
294 static int lpc32xx_nand_device_ready(struct nand_chip *nand_chip)
295 {
296 	struct lpc32xx_nand_host *host = nand_get_controller_data(nand_chip);
297 
298 	if ((readb(MLC_ISR(host->io_base)) &
299 	     (MLCISR_CONTROLLER_READY | MLCISR_NAND_READY)) ==
300 	    (MLCISR_CONTROLLER_READY | MLCISR_NAND_READY))
301 		return  1;
302 
303 	return 0;
304 }
305 
306 static irqreturn_t lpc3xxx_nand_irq(int irq, struct lpc32xx_nand_host *host)
307 {
308 	uint8_t sr;
309 
310 	/* Clear interrupt flag by reading status */
311 	sr = readb(MLC_IRQ_SR(host->io_base));
312 	if (sr & MLCIRQ_NAND_READY)
313 		complete(&host->comp_nand);
314 	if (sr & MLCIRQ_CONTROLLER_READY)
315 		complete(&host->comp_controller);
316 
317 	return IRQ_HANDLED;
318 }
319 
320 static int lpc32xx_waitfunc_nand(struct nand_chip *chip)
321 {
322 	struct mtd_info *mtd = nand_to_mtd(chip);
323 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
324 
325 	if (readb(MLC_ISR(host->io_base)) & MLCISR_NAND_READY)
326 		goto exit;
327 
328 	wait_for_completion(&host->comp_nand);
329 
330 	while (!(readb(MLC_ISR(host->io_base)) & MLCISR_NAND_READY)) {
331 		/* Seems to be delayed sometimes by controller */
332 		dev_dbg(&mtd->dev, "Warning: NAND not ready.\n");
333 		cpu_relax();
334 	}
335 
336 exit:
337 	return NAND_STATUS_READY;
338 }
339 
340 static int lpc32xx_waitfunc_controller(struct nand_chip *chip)
341 {
342 	struct mtd_info *mtd = nand_to_mtd(chip);
343 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
344 
345 	if (readb(MLC_ISR(host->io_base)) & MLCISR_CONTROLLER_READY)
346 		goto exit;
347 
348 	wait_for_completion(&host->comp_controller);
349 
350 	while (!(readb(MLC_ISR(host->io_base)) &
351 		 MLCISR_CONTROLLER_READY)) {
352 		dev_dbg(&mtd->dev, "Warning: Controller not ready.\n");
353 		cpu_relax();
354 	}
355 
356 exit:
357 	return NAND_STATUS_READY;
358 }
359 
360 static int lpc32xx_waitfunc(struct nand_chip *chip)
361 {
362 	lpc32xx_waitfunc_nand(chip);
363 	lpc32xx_waitfunc_controller(chip);
364 
365 	return NAND_STATUS_READY;
366 }
367 
368 /*
369  * Enable NAND write protect
370  */
371 static void lpc32xx_wp_enable(struct lpc32xx_nand_host *host)
372 {
373 	if (gpio_is_valid(host->ncfg->wp_gpio))
374 		gpio_set_value(host->ncfg->wp_gpio, 0);
375 }
376 
377 /*
378  * Disable NAND write protect
379  */
380 static void lpc32xx_wp_disable(struct lpc32xx_nand_host *host)
381 {
382 	if (gpio_is_valid(host->ncfg->wp_gpio))
383 		gpio_set_value(host->ncfg->wp_gpio, 1);
384 }
385 
386 static void lpc32xx_dma_complete_func(void *completion)
387 {
388 	complete(completion);
389 }
390 
391 static int lpc32xx_xmit_dma(struct mtd_info *mtd, void *mem, int len,
392 			    enum dma_transfer_direction dir)
393 {
394 	struct nand_chip *chip = mtd_to_nand(mtd);
395 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
396 	struct dma_async_tx_descriptor *desc;
397 	int flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
398 	int res;
399 
400 	sg_init_one(&host->sgl, mem, len);
401 
402 	res = dma_map_sg(host->dma_chan->device->dev, &host->sgl, 1,
403 			 DMA_BIDIRECTIONAL);
404 	if (res != 1) {
405 		dev_err(mtd->dev.parent, "Failed to map sg list\n");
406 		return -ENXIO;
407 	}
408 	desc = dmaengine_prep_slave_sg(host->dma_chan, &host->sgl, 1, dir,
409 				       flags);
410 	if (!desc) {
411 		dev_err(mtd->dev.parent, "Failed to prepare slave sg\n");
412 		goto out1;
413 	}
414 
415 	init_completion(&host->comp_dma);
416 	desc->callback = lpc32xx_dma_complete_func;
417 	desc->callback_param = &host->comp_dma;
418 
419 	dmaengine_submit(desc);
420 	dma_async_issue_pending(host->dma_chan);
421 
422 	wait_for_completion_timeout(&host->comp_dma, msecs_to_jiffies(1000));
423 
424 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
425 		     DMA_BIDIRECTIONAL);
426 	return 0;
427 out1:
428 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
429 		     DMA_BIDIRECTIONAL);
430 	return -ENXIO;
431 }
432 
433 static int lpc32xx_read_page(struct nand_chip *chip, uint8_t *buf,
434 			     int oob_required, int page)
435 {
436 	struct mtd_info *mtd = nand_to_mtd(chip);
437 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
438 	int i, j;
439 	uint8_t *oobbuf = chip->oob_poi;
440 	uint32_t mlc_isr;
441 	int res;
442 	uint8_t *dma_buf;
443 	bool dma_mapped;
444 
445 	if ((void *)buf <= high_memory) {
446 		dma_buf = buf;
447 		dma_mapped = true;
448 	} else {
449 		dma_buf = host->dma_buf;
450 		dma_mapped = false;
451 	}
452 
453 	/* Writing Command and Address */
454 	nand_read_page_op(chip, page, 0, NULL, 0);
455 
456 	/* For all sub-pages */
457 	for (i = 0; i < host->mlcsubpages; i++) {
458 		/* Start Auto Decode Command */
459 		writeb(0x00, MLC_ECC_AUTO_DEC_REG(host->io_base));
460 
461 		/* Wait for Controller Ready */
462 		lpc32xx_waitfunc_controller(chip);
463 
464 		/* Check ECC Error status */
465 		mlc_isr = readl(MLC_ISR(host->io_base));
466 		if (mlc_isr & MLCISR_DECODER_FAILURE) {
467 			mtd->ecc_stats.failed++;
468 			dev_warn(&mtd->dev, "%s: DECODER_FAILURE\n", __func__);
469 		} else if (mlc_isr & MLCISR_ERRORS_DETECTED) {
470 			mtd->ecc_stats.corrected += ((mlc_isr >> 4) & 0x3) + 1;
471 		}
472 
473 		/* Read 512 + 16 Bytes */
474 		if (use_dma) {
475 			res = lpc32xx_xmit_dma(mtd, dma_buf + i * 512, 512,
476 					       DMA_DEV_TO_MEM);
477 			if (res)
478 				return res;
479 		} else {
480 			for (j = 0; j < (512 >> 2); j++) {
481 				*((uint32_t *)(buf)) =
482 					readl(MLC_BUFF(host->io_base));
483 				buf += 4;
484 			}
485 		}
486 		for (j = 0; j < (16 >> 2); j++) {
487 			*((uint32_t *)(oobbuf)) =
488 				readl(MLC_BUFF(host->io_base));
489 			oobbuf += 4;
490 		}
491 	}
492 
493 	if (use_dma && !dma_mapped)
494 		memcpy(buf, dma_buf, mtd->writesize);
495 
496 	return 0;
497 }
498 
499 static int lpc32xx_write_page_lowlevel(struct nand_chip *chip,
500 				       const uint8_t *buf, int oob_required,
501 				       int page)
502 {
503 	struct mtd_info *mtd = nand_to_mtd(chip);
504 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
505 	const uint8_t *oobbuf = chip->oob_poi;
506 	uint8_t *dma_buf = (uint8_t *)buf;
507 	int res;
508 	int i, j;
509 
510 	if (use_dma && (void *)buf >= high_memory) {
511 		dma_buf = host->dma_buf;
512 		memcpy(dma_buf, buf, mtd->writesize);
513 	}
514 
515 	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
516 
517 	for (i = 0; i < host->mlcsubpages; i++) {
518 		/* Start Encode */
519 		writeb(0x00, MLC_ECC_ENC_REG(host->io_base));
520 
521 		/* Write 512 + 6 Bytes to Buffer */
522 		if (use_dma) {
523 			res = lpc32xx_xmit_dma(mtd, dma_buf + i * 512, 512,
524 					       DMA_MEM_TO_DEV);
525 			if (res)
526 				return res;
527 		} else {
528 			for (j = 0; j < (512 >> 2); j++) {
529 				writel(*((uint32_t *)(buf)),
530 				       MLC_BUFF(host->io_base));
531 				buf += 4;
532 			}
533 		}
534 		writel(*((uint32_t *)(oobbuf)), MLC_BUFF(host->io_base));
535 		oobbuf += 4;
536 		writew(*((uint16_t *)(oobbuf)), MLC_BUFF(host->io_base));
537 		oobbuf += 12;
538 
539 		/* Auto Encode w/ Bit 8 = 0 (see LPC MLC Controller manual) */
540 		writeb(0x00, MLC_ECC_AUTO_ENC_REG(host->io_base));
541 
542 		/* Wait for Controller Ready */
543 		lpc32xx_waitfunc_controller(chip);
544 	}
545 
546 	return nand_prog_page_end_op(chip);
547 }
548 
549 static int lpc32xx_read_oob(struct nand_chip *chip, int page)
550 {
551 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
552 
553 	/* Read whole page - necessary with MLC controller! */
554 	lpc32xx_read_page(chip, host->dummy_buf, 1, page);
555 
556 	return 0;
557 }
558 
559 static int lpc32xx_write_oob(struct nand_chip *chip, int page)
560 {
561 	/* None, write_oob conflicts with the automatic LPC MLC ECC decoder! */
562 	return 0;
563 }
564 
565 /* Prepares MLC for transfers with H/W ECC enabled: always enabled anyway */
566 static void lpc32xx_ecc_enable(struct nand_chip *chip, int mode)
567 {
568 	/* Always enabled! */
569 }
570 
571 static int lpc32xx_dma_setup(struct lpc32xx_nand_host *host)
572 {
573 	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
574 	dma_cap_mask_t mask;
575 
576 	if (!host->pdata || !host->pdata->dma_filter) {
577 		dev_err(mtd->dev.parent, "no DMA platform data\n");
578 		return -ENOENT;
579 	}
580 
581 	dma_cap_zero(mask);
582 	dma_cap_set(DMA_SLAVE, mask);
583 	host->dma_chan = dma_request_channel(mask, host->pdata->dma_filter,
584 					     "nand-mlc");
585 	if (!host->dma_chan) {
586 		dev_err(mtd->dev.parent, "Failed to request DMA channel\n");
587 		return -EBUSY;
588 	}
589 
590 	/*
591 	 * Set direction to a sensible value even if the dmaengine driver
592 	 * should ignore it. With the default (DMA_MEM_TO_MEM), the amba-pl08x
593 	 * driver criticizes it as "alien transfer direction".
594 	 */
595 	host->dma_slave_config.direction = DMA_DEV_TO_MEM;
596 	host->dma_slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
597 	host->dma_slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
598 	host->dma_slave_config.src_maxburst = 128;
599 	host->dma_slave_config.dst_maxburst = 128;
600 	/* DMA controller does flow control: */
601 	host->dma_slave_config.device_fc = false;
602 	host->dma_slave_config.src_addr = MLC_BUFF(host->io_base_phy);
603 	host->dma_slave_config.dst_addr = MLC_BUFF(host->io_base_phy);
604 	if (dmaengine_slave_config(host->dma_chan, &host->dma_slave_config)) {
605 		dev_err(mtd->dev.parent, "Failed to setup DMA slave\n");
606 		goto out1;
607 	}
608 
609 	return 0;
610 out1:
611 	dma_release_channel(host->dma_chan);
612 	return -ENXIO;
613 }
614 
615 static struct lpc32xx_nand_cfg_mlc *lpc32xx_parse_dt(struct device *dev)
616 {
617 	struct lpc32xx_nand_cfg_mlc *ncfg;
618 	struct device_node *np = dev->of_node;
619 
620 	ncfg = devm_kzalloc(dev, sizeof(*ncfg), GFP_KERNEL);
621 	if (!ncfg)
622 		return NULL;
623 
624 	of_property_read_u32(np, "nxp,tcea-delay", &ncfg->tcea_delay);
625 	of_property_read_u32(np, "nxp,busy-delay", &ncfg->busy_delay);
626 	of_property_read_u32(np, "nxp,nand-ta", &ncfg->nand_ta);
627 	of_property_read_u32(np, "nxp,rd-high", &ncfg->rd_high);
628 	of_property_read_u32(np, "nxp,rd-low", &ncfg->rd_low);
629 	of_property_read_u32(np, "nxp,wr-high", &ncfg->wr_high);
630 	of_property_read_u32(np, "nxp,wr-low", &ncfg->wr_low);
631 
632 	if (!ncfg->tcea_delay || !ncfg->busy_delay || !ncfg->nand_ta ||
633 	    !ncfg->rd_high || !ncfg->rd_low || !ncfg->wr_high ||
634 	    !ncfg->wr_low) {
635 		dev_err(dev, "chip parameters not specified correctly\n");
636 		return NULL;
637 	}
638 
639 	ncfg->wp_gpio = of_get_named_gpio(np, "gpios", 0);
640 
641 	return ncfg;
642 }
643 
644 static int lpc32xx_nand_attach_chip(struct nand_chip *chip)
645 {
646 	struct mtd_info *mtd = nand_to_mtd(chip);
647 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
648 	struct device *dev = &host->pdev->dev;
649 
650 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
651 		return 0;
652 
653 	host->dma_buf = devm_kzalloc(dev, mtd->writesize, GFP_KERNEL);
654 	if (!host->dma_buf)
655 		return -ENOMEM;
656 
657 	host->dummy_buf = devm_kzalloc(dev, mtd->writesize, GFP_KERNEL);
658 	if (!host->dummy_buf)
659 		return -ENOMEM;
660 
661 	chip->ecc.size = 512;
662 	chip->ecc.hwctl = lpc32xx_ecc_enable;
663 	chip->ecc.read_page_raw = lpc32xx_read_page;
664 	chip->ecc.read_page = lpc32xx_read_page;
665 	chip->ecc.write_page_raw = lpc32xx_write_page_lowlevel;
666 	chip->ecc.write_page = lpc32xx_write_page_lowlevel;
667 	chip->ecc.write_oob = lpc32xx_write_oob;
668 	chip->ecc.read_oob = lpc32xx_read_oob;
669 	chip->ecc.strength = 4;
670 	chip->ecc.bytes = 10;
671 
672 	mtd_set_ooblayout(mtd, &lpc32xx_ooblayout_ops);
673 	host->mlcsubpages = mtd->writesize / 512;
674 
675 	return 0;
676 }
677 
678 static const struct nand_controller_ops lpc32xx_nand_controller_ops = {
679 	.attach_chip = lpc32xx_nand_attach_chip,
680 };
681 
682 /*
683  * Probe for NAND controller
684  */
685 static int lpc32xx_nand_probe(struct platform_device *pdev)
686 {
687 	struct lpc32xx_nand_host *host;
688 	struct mtd_info *mtd;
689 	struct nand_chip *nand_chip;
690 	struct resource *rc;
691 	int res;
692 
693 	/* Allocate memory for the device structure (and zero it) */
694 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
695 	if (!host)
696 		return -ENOMEM;
697 
698 	host->pdev = pdev;
699 
700 	rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
701 	host->io_base = devm_ioremap_resource(&pdev->dev, rc);
702 	if (IS_ERR(host->io_base))
703 		return PTR_ERR(host->io_base);
704 
705 	host->io_base_phy = rc->start;
706 
707 	nand_chip = &host->nand_chip;
708 	mtd = nand_to_mtd(nand_chip);
709 	if (pdev->dev.of_node)
710 		host->ncfg = lpc32xx_parse_dt(&pdev->dev);
711 	if (!host->ncfg) {
712 		dev_err(&pdev->dev,
713 			"Missing or bad NAND config from device tree\n");
714 		return -ENOENT;
715 	}
716 	if (host->ncfg->wp_gpio == -EPROBE_DEFER)
717 		return -EPROBE_DEFER;
718 	if (gpio_is_valid(host->ncfg->wp_gpio) &&
719 			gpio_request(host->ncfg->wp_gpio, "NAND WP")) {
720 		dev_err(&pdev->dev, "GPIO not available\n");
721 		return -EBUSY;
722 	}
723 	lpc32xx_wp_disable(host);
724 
725 	host->pdata = dev_get_platdata(&pdev->dev);
726 
727 	/* link the private data structures */
728 	nand_set_controller_data(nand_chip, host);
729 	nand_set_flash_node(nand_chip, pdev->dev.of_node);
730 	mtd->dev.parent = &pdev->dev;
731 
732 	/* Get NAND clock */
733 	host->clk = clk_get(&pdev->dev, NULL);
734 	if (IS_ERR(host->clk)) {
735 		dev_err(&pdev->dev, "Clock initialization failure\n");
736 		res = -ENOENT;
737 		goto free_gpio;
738 	}
739 	res = clk_prepare_enable(host->clk);
740 	if (res)
741 		goto put_clk;
742 
743 	nand_chip->legacy.cmd_ctrl = lpc32xx_nand_cmd_ctrl;
744 	nand_chip->legacy.dev_ready = lpc32xx_nand_device_ready;
745 	nand_chip->legacy.chip_delay = 25; /* us */
746 	nand_chip->legacy.IO_ADDR_R = MLC_DATA(host->io_base);
747 	nand_chip->legacy.IO_ADDR_W = MLC_DATA(host->io_base);
748 
749 	/* Init NAND controller */
750 	lpc32xx_nand_setup(host);
751 
752 	platform_set_drvdata(pdev, host);
753 
754 	/* Initialize function pointers */
755 	nand_chip->legacy.waitfunc = lpc32xx_waitfunc;
756 
757 	nand_chip->options = NAND_NO_SUBPAGE_WRITE;
758 	nand_chip->bbt_options = NAND_BBT_USE_FLASH | NAND_BBT_NO_OOB;
759 	nand_chip->bbt_td = &lpc32xx_nand_bbt;
760 	nand_chip->bbt_md = &lpc32xx_nand_bbt_mirror;
761 
762 	if (use_dma) {
763 		res = lpc32xx_dma_setup(host);
764 		if (res) {
765 			res = -EIO;
766 			goto unprepare_clk;
767 		}
768 	}
769 
770 	/* initially clear interrupt status */
771 	readb(MLC_IRQ_SR(host->io_base));
772 
773 	init_completion(&host->comp_nand);
774 	init_completion(&host->comp_controller);
775 
776 	host->irq = platform_get_irq(pdev, 0);
777 	if (host->irq < 0) {
778 		res = -EINVAL;
779 		goto release_dma_chan;
780 	}
781 
782 	if (request_irq(host->irq, (irq_handler_t)&lpc3xxx_nand_irq,
783 			IRQF_TRIGGER_HIGH, DRV_NAME, host)) {
784 		dev_err(&pdev->dev, "Error requesting NAND IRQ\n");
785 		res = -ENXIO;
786 		goto release_dma_chan;
787 	}
788 
789 	/*
790 	 * Scan to find existence of the device and get the type of NAND device:
791 	 * SMALL block or LARGE block.
792 	 */
793 	nand_chip->legacy.dummy_controller.ops = &lpc32xx_nand_controller_ops;
794 	res = nand_scan(nand_chip, 1);
795 	if (res)
796 		goto free_irq;
797 
798 	mtd->name = DRV_NAME;
799 
800 	res = mtd_device_register(mtd, host->ncfg->parts,
801 				  host->ncfg->num_parts);
802 	if (res)
803 		goto cleanup_nand;
804 
805 	return 0;
806 
807 cleanup_nand:
808 	nand_cleanup(nand_chip);
809 free_irq:
810 	free_irq(host->irq, host);
811 release_dma_chan:
812 	if (use_dma)
813 		dma_release_channel(host->dma_chan);
814 unprepare_clk:
815 	clk_disable_unprepare(host->clk);
816 put_clk:
817 	clk_put(host->clk);
818 free_gpio:
819 	lpc32xx_wp_enable(host);
820 	gpio_free(host->ncfg->wp_gpio);
821 
822 	return res;
823 }
824 
825 /*
826  * Remove NAND device
827  */
828 static int lpc32xx_nand_remove(struct platform_device *pdev)
829 {
830 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
831 	struct nand_chip *chip = &host->nand_chip;
832 	int ret;
833 
834 	ret = mtd_device_unregister(nand_to_mtd(chip));
835 	WARN_ON(ret);
836 	nand_cleanup(chip);
837 
838 	free_irq(host->irq, host);
839 	if (use_dma)
840 		dma_release_channel(host->dma_chan);
841 
842 	clk_disable_unprepare(host->clk);
843 	clk_put(host->clk);
844 
845 	lpc32xx_wp_enable(host);
846 	gpio_free(host->ncfg->wp_gpio);
847 
848 	return 0;
849 }
850 
851 #ifdef CONFIG_PM
852 static int lpc32xx_nand_resume(struct platform_device *pdev)
853 {
854 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
855 	int ret;
856 
857 	/* Re-enable NAND clock */
858 	ret = clk_prepare_enable(host->clk);
859 	if (ret)
860 		return ret;
861 
862 	/* Fresh init of NAND controller */
863 	lpc32xx_nand_setup(host);
864 
865 	/* Disable write protect */
866 	lpc32xx_wp_disable(host);
867 
868 	return 0;
869 }
870 
871 static int lpc32xx_nand_suspend(struct platform_device *pdev, pm_message_t pm)
872 {
873 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
874 
875 	/* Enable write protect for safety */
876 	lpc32xx_wp_enable(host);
877 
878 	/* Disable clock */
879 	clk_disable_unprepare(host->clk);
880 	return 0;
881 }
882 
883 #else
884 #define lpc32xx_nand_resume NULL
885 #define lpc32xx_nand_suspend NULL
886 #endif
887 
888 static const struct of_device_id lpc32xx_nand_match[] = {
889 	{ .compatible = "nxp,lpc3220-mlc" },
890 	{ /* sentinel */ },
891 };
892 MODULE_DEVICE_TABLE(of, lpc32xx_nand_match);
893 
894 static struct platform_driver lpc32xx_nand_driver = {
895 	.probe		= lpc32xx_nand_probe,
896 	.remove		= lpc32xx_nand_remove,
897 	.resume		= lpc32xx_nand_resume,
898 	.suspend	= lpc32xx_nand_suspend,
899 	.driver		= {
900 		.name	= DRV_NAME,
901 		.of_match_table = lpc32xx_nand_match,
902 	},
903 };
904 
905 module_platform_driver(lpc32xx_nand_driver);
906 
907 MODULE_LICENSE("GPL");
908 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
909 MODULE_DESCRIPTION("NAND driver for the NXP LPC32XX MLC controller");
910