xref: /openbmc/linux/drivers/mtd/nand/raw/lpc32xx_slc.c (revision f1575595)
1 /*
2  * NXP LPC32XX NAND SLC driver
3  *
4  * Authors:
5  *    Kevin Wells <kevin.wells@nxp.com>
6  *    Roland Stigge <stigge@antcom.de>
7  *
8  * Copyright © 2011 NXP Semiconductors
9  * Copyright © 2012 Roland Stigge
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  */
21 
22 #include <linux/slab.h>
23 #include <linux/module.h>
24 #include <linux/platform_device.h>
25 #include <linux/mtd/mtd.h>
26 #include <linux/mtd/rawnand.h>
27 #include <linux/mtd/partitions.h>
28 #include <linux/clk.h>
29 #include <linux/err.h>
30 #include <linux/delay.h>
31 #include <linux/io.h>
32 #include <linux/mm.h>
33 #include <linux/dma-mapping.h>
34 #include <linux/dmaengine.h>
35 #include <linux/mtd/nand_ecc.h>
36 #include <linux/gpio.h>
37 #include <linux/of.h>
38 #include <linux/of_gpio.h>
39 #include <linux/mtd/lpc32xx_slc.h>
40 
41 #define LPC32XX_MODNAME		"lpc32xx-nand"
42 
43 /**********************************************************************
44 * SLC NAND controller register offsets
45 **********************************************************************/
46 
47 #define SLC_DATA(x)		(x + 0x000)
48 #define SLC_ADDR(x)		(x + 0x004)
49 #define SLC_CMD(x)		(x + 0x008)
50 #define SLC_STOP(x)		(x + 0x00C)
51 #define SLC_CTRL(x)		(x + 0x010)
52 #define SLC_CFG(x)		(x + 0x014)
53 #define SLC_STAT(x)		(x + 0x018)
54 #define SLC_INT_STAT(x)		(x + 0x01C)
55 #define SLC_IEN(x)		(x + 0x020)
56 #define SLC_ISR(x)		(x + 0x024)
57 #define SLC_ICR(x)		(x + 0x028)
58 #define SLC_TAC(x)		(x + 0x02C)
59 #define SLC_TC(x)		(x + 0x030)
60 #define SLC_ECC(x)		(x + 0x034)
61 #define SLC_DMA_DATA(x)		(x + 0x038)
62 
63 /**********************************************************************
64 * slc_ctrl register definitions
65 **********************************************************************/
66 #define SLCCTRL_SW_RESET	(1 << 2) /* Reset the NAND controller bit */
67 #define SLCCTRL_ECC_CLEAR	(1 << 1) /* Reset ECC bit */
68 #define SLCCTRL_DMA_START	(1 << 0) /* Start DMA channel bit */
69 
70 /**********************************************************************
71 * slc_cfg register definitions
72 **********************************************************************/
73 #define SLCCFG_CE_LOW		(1 << 5) /* Force CE low bit */
74 #define SLCCFG_DMA_ECC		(1 << 4) /* Enable DMA ECC bit */
75 #define SLCCFG_ECC_EN		(1 << 3) /* ECC enable bit */
76 #define SLCCFG_DMA_BURST	(1 << 2) /* DMA burst bit */
77 #define SLCCFG_DMA_DIR		(1 << 1) /* DMA write(0)/read(1) bit */
78 #define SLCCFG_WIDTH		(1 << 0) /* External device width, 0=8bit */
79 
80 /**********************************************************************
81 * slc_stat register definitions
82 **********************************************************************/
83 #define SLCSTAT_DMA_FIFO	(1 << 2) /* DMA FIFO has data bit */
84 #define SLCSTAT_SLC_FIFO	(1 << 1) /* SLC FIFO has data bit */
85 #define SLCSTAT_NAND_READY	(1 << 0) /* NAND device is ready bit */
86 
87 /**********************************************************************
88 * slc_int_stat, slc_ien, slc_isr, and slc_icr register definitions
89 **********************************************************************/
90 #define SLCSTAT_INT_TC		(1 << 1) /* Transfer count bit */
91 #define SLCSTAT_INT_RDY_EN	(1 << 0) /* Ready interrupt bit */
92 
93 /**********************************************************************
94 * slc_tac register definitions
95 **********************************************************************/
96 /* Computation of clock cycles on basis of controller and device clock rates */
97 #define SLCTAC_CLOCKS(c, n, s)	(min_t(u32, DIV_ROUND_UP(c, n) - 1, 0xF) << s)
98 
99 /* Clock setting for RDY write sample wait time in 2*n clocks */
100 #define SLCTAC_WDR(n)		(((n) & 0xF) << 28)
101 /* Write pulse width in clock cycles, 1 to 16 clocks */
102 #define SLCTAC_WWIDTH(c, n)	(SLCTAC_CLOCKS(c, n, 24))
103 /* Write hold time of control and data signals, 1 to 16 clocks */
104 #define SLCTAC_WHOLD(c, n)	(SLCTAC_CLOCKS(c, n, 20))
105 /* Write setup time of control and data signals, 1 to 16 clocks */
106 #define SLCTAC_WSETUP(c, n)	(SLCTAC_CLOCKS(c, n, 16))
107 /* Clock setting for RDY read sample wait time in 2*n clocks */
108 #define SLCTAC_RDR(n)		(((n) & 0xF) << 12)
109 /* Read pulse width in clock cycles, 1 to 16 clocks */
110 #define SLCTAC_RWIDTH(c, n)	(SLCTAC_CLOCKS(c, n, 8))
111 /* Read hold time of control and data signals, 1 to 16 clocks */
112 #define SLCTAC_RHOLD(c, n)	(SLCTAC_CLOCKS(c, n, 4))
113 /* Read setup time of control and data signals, 1 to 16 clocks */
114 #define SLCTAC_RSETUP(c, n)	(SLCTAC_CLOCKS(c, n, 0))
115 
116 /**********************************************************************
117 * slc_ecc register definitions
118 **********************************************************************/
119 /* ECC line party fetch macro */
120 #define SLCECC_TO_LINEPAR(n)	(((n) >> 6) & 0x7FFF)
121 #define SLCECC_TO_COLPAR(n)	((n) & 0x3F)
122 
123 /*
124  * DMA requires storage space for the DMA local buffer and the hardware ECC
125  * storage area. The DMA local buffer is only used if DMA mapping fails
126  * during runtime.
127  */
128 #define LPC32XX_DMA_DATA_SIZE		4096
129 #define LPC32XX_ECC_SAVE_SIZE		((4096 / 256) * 4)
130 
131 /* Number of bytes used for ECC stored in NAND per 256 bytes */
132 #define LPC32XX_SLC_DEV_ECC_BYTES	3
133 
134 /*
135  * If the NAND base clock frequency can't be fetched, this frequency will be
136  * used instead as the base. This rate is used to setup the timing registers
137  * used for NAND accesses.
138  */
139 #define LPC32XX_DEF_BUS_RATE		133250000
140 
141 /* Milliseconds for DMA FIFO timeout (unlikely anyway) */
142 #define LPC32XX_DMA_TIMEOUT		100
143 
144 /*
145  * NAND ECC Layout for small page NAND devices
146  * Note: For large and huge page devices, the default layouts are used
147  */
148 static int lpc32xx_ooblayout_ecc(struct mtd_info *mtd, int section,
149 				 struct mtd_oob_region *oobregion)
150 {
151 	if (section)
152 		return -ERANGE;
153 
154 	oobregion->length = 6;
155 	oobregion->offset = 10;
156 
157 	return 0;
158 }
159 
160 static int lpc32xx_ooblayout_free(struct mtd_info *mtd, int section,
161 				  struct mtd_oob_region *oobregion)
162 {
163 	if (section > 1)
164 		return -ERANGE;
165 
166 	if (!section) {
167 		oobregion->offset = 0;
168 		oobregion->length = 4;
169 	} else {
170 		oobregion->offset = 6;
171 		oobregion->length = 4;
172 	}
173 
174 	return 0;
175 }
176 
177 static const struct mtd_ooblayout_ops lpc32xx_ooblayout_ops = {
178 	.ecc = lpc32xx_ooblayout_ecc,
179 	.free = lpc32xx_ooblayout_free,
180 };
181 
182 static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
183 static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
184 
185 /*
186  * Small page FLASH BBT descriptors, marker at offset 0, version at offset 6
187  * Note: Large page devices used the default layout
188  */
189 static struct nand_bbt_descr bbt_smallpage_main_descr = {
190 	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
191 		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
192 	.offs =	0,
193 	.len = 4,
194 	.veroffs = 6,
195 	.maxblocks = 4,
196 	.pattern = bbt_pattern
197 };
198 
199 static struct nand_bbt_descr bbt_smallpage_mirror_descr = {
200 	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
201 		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
202 	.offs =	0,
203 	.len = 4,
204 	.veroffs = 6,
205 	.maxblocks = 4,
206 	.pattern = mirror_pattern
207 };
208 
209 /*
210  * NAND platform configuration structure
211  */
212 struct lpc32xx_nand_cfg_slc {
213 	uint32_t wdr_clks;
214 	uint32_t wwidth;
215 	uint32_t whold;
216 	uint32_t wsetup;
217 	uint32_t rdr_clks;
218 	uint32_t rwidth;
219 	uint32_t rhold;
220 	uint32_t rsetup;
221 	int wp_gpio;
222 	struct mtd_partition *parts;
223 	unsigned num_parts;
224 };
225 
226 struct lpc32xx_nand_host {
227 	struct nand_chip	nand_chip;
228 	struct lpc32xx_slc_platform_data *pdata;
229 	struct clk		*clk;
230 	void __iomem		*io_base;
231 	struct lpc32xx_nand_cfg_slc *ncfg;
232 
233 	struct completion	comp;
234 	struct dma_chan		*dma_chan;
235 	uint32_t		dma_buf_len;
236 	struct dma_slave_config	dma_slave_config;
237 	struct scatterlist	sgl;
238 
239 	/*
240 	 * DMA and CPU addresses of ECC work area and data buffer
241 	 */
242 	uint32_t		*ecc_buf;
243 	uint8_t			*data_buf;
244 	dma_addr_t		io_base_dma;
245 };
246 
247 static void lpc32xx_nand_setup(struct lpc32xx_nand_host *host)
248 {
249 	uint32_t clkrate, tmp;
250 
251 	/* Reset SLC controller */
252 	writel(SLCCTRL_SW_RESET, SLC_CTRL(host->io_base));
253 	udelay(1000);
254 
255 	/* Basic setup */
256 	writel(0, SLC_CFG(host->io_base));
257 	writel(0, SLC_IEN(host->io_base));
258 	writel((SLCSTAT_INT_TC | SLCSTAT_INT_RDY_EN),
259 		SLC_ICR(host->io_base));
260 
261 	/* Get base clock for SLC block */
262 	clkrate = clk_get_rate(host->clk);
263 	if (clkrate == 0)
264 		clkrate = LPC32XX_DEF_BUS_RATE;
265 
266 	/* Compute clock setup values */
267 	tmp = SLCTAC_WDR(host->ncfg->wdr_clks) |
268 		SLCTAC_WWIDTH(clkrate, host->ncfg->wwidth) |
269 		SLCTAC_WHOLD(clkrate, host->ncfg->whold) |
270 		SLCTAC_WSETUP(clkrate, host->ncfg->wsetup) |
271 		SLCTAC_RDR(host->ncfg->rdr_clks) |
272 		SLCTAC_RWIDTH(clkrate, host->ncfg->rwidth) |
273 		SLCTAC_RHOLD(clkrate, host->ncfg->rhold) |
274 		SLCTAC_RSETUP(clkrate, host->ncfg->rsetup);
275 	writel(tmp, SLC_TAC(host->io_base));
276 }
277 
278 /*
279  * Hardware specific access to control lines
280  */
281 static void lpc32xx_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
282 	unsigned int ctrl)
283 {
284 	uint32_t tmp;
285 	struct nand_chip *chip = mtd_to_nand(mtd);
286 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
287 
288 	/* Does CE state need to be changed? */
289 	tmp = readl(SLC_CFG(host->io_base));
290 	if (ctrl & NAND_NCE)
291 		tmp |= SLCCFG_CE_LOW;
292 	else
293 		tmp &= ~SLCCFG_CE_LOW;
294 	writel(tmp, SLC_CFG(host->io_base));
295 
296 	if (cmd != NAND_CMD_NONE) {
297 		if (ctrl & NAND_CLE)
298 			writel(cmd, SLC_CMD(host->io_base));
299 		else
300 			writel(cmd, SLC_ADDR(host->io_base));
301 	}
302 }
303 
304 /*
305  * Read the Device Ready pin
306  */
307 static int lpc32xx_nand_device_ready(struct mtd_info *mtd)
308 {
309 	struct nand_chip *chip = mtd_to_nand(mtd);
310 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
311 	int rdy = 0;
312 
313 	if ((readl(SLC_STAT(host->io_base)) & SLCSTAT_NAND_READY) != 0)
314 		rdy = 1;
315 
316 	return rdy;
317 }
318 
319 /*
320  * Enable NAND write protect
321  */
322 static void lpc32xx_wp_enable(struct lpc32xx_nand_host *host)
323 {
324 	if (gpio_is_valid(host->ncfg->wp_gpio))
325 		gpio_set_value(host->ncfg->wp_gpio, 0);
326 }
327 
328 /*
329  * Disable NAND write protect
330  */
331 static void lpc32xx_wp_disable(struct lpc32xx_nand_host *host)
332 {
333 	if (gpio_is_valid(host->ncfg->wp_gpio))
334 		gpio_set_value(host->ncfg->wp_gpio, 1);
335 }
336 
337 /*
338  * Prepares SLC for transfers with H/W ECC enabled
339  */
340 static void lpc32xx_nand_ecc_enable(struct mtd_info *mtd, int mode)
341 {
342 	/* Hardware ECC is enabled automatically in hardware as needed */
343 }
344 
345 /*
346  * Calculates the ECC for the data
347  */
348 static int lpc32xx_nand_ecc_calculate(struct mtd_info *mtd,
349 				      const unsigned char *buf,
350 				      unsigned char *code)
351 {
352 	/*
353 	 * ECC is calculated automatically in hardware during syndrome read
354 	 * and write operations, so it doesn't need to be calculated here.
355 	 */
356 	return 0;
357 }
358 
359 /*
360  * Read a single byte from NAND device
361  */
362 static uint8_t lpc32xx_nand_read_byte(struct mtd_info *mtd)
363 {
364 	struct nand_chip *chip = mtd_to_nand(mtd);
365 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
366 
367 	return (uint8_t)readl(SLC_DATA(host->io_base));
368 }
369 
370 /*
371  * Simple device read without ECC
372  */
373 static void lpc32xx_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
374 {
375 	struct nand_chip *chip = mtd_to_nand(mtd);
376 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
377 
378 	/* Direct device read with no ECC */
379 	while (len-- > 0)
380 		*buf++ = (uint8_t)readl(SLC_DATA(host->io_base));
381 }
382 
383 /*
384  * Simple device write without ECC
385  */
386 static void lpc32xx_nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
387 {
388 	struct nand_chip *chip = mtd_to_nand(mtd);
389 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
390 
391 	/* Direct device write with no ECC */
392 	while (len-- > 0)
393 		writel((uint32_t)*buf++, SLC_DATA(host->io_base));
394 }
395 
396 /*
397  * Read the OOB data from the device without ECC using FIFO method
398  */
399 static int lpc32xx_nand_read_oob_syndrome(struct mtd_info *mtd,
400 					  struct nand_chip *chip, int page)
401 {
402 	return nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
403 }
404 
405 /*
406  * Write the OOB data to the device without ECC using FIFO method
407  */
408 static int lpc32xx_nand_write_oob_syndrome(struct mtd_info *mtd,
409 	struct nand_chip *chip, int page)
410 {
411 	return nand_prog_page_op(chip, page, mtd->writesize, chip->oob_poi,
412 				 mtd->oobsize);
413 }
414 
415 /*
416  * Fills in the ECC fields in the OOB buffer with the hardware generated ECC
417  */
418 static void lpc32xx_slc_ecc_copy(uint8_t *spare, const uint32_t *ecc, int count)
419 {
420 	int i;
421 
422 	for (i = 0; i < (count * 3); i += 3) {
423 		uint32_t ce = ecc[i / 3];
424 		ce = ~(ce << 2) & 0xFFFFFF;
425 		spare[i + 2] = (uint8_t)(ce & 0xFF);
426 		ce >>= 8;
427 		spare[i + 1] = (uint8_t)(ce & 0xFF);
428 		ce >>= 8;
429 		spare[i] = (uint8_t)(ce & 0xFF);
430 	}
431 }
432 
433 static void lpc32xx_dma_complete_func(void *completion)
434 {
435 	complete(completion);
436 }
437 
438 static int lpc32xx_xmit_dma(struct mtd_info *mtd, dma_addr_t dma,
439 			    void *mem, int len, enum dma_transfer_direction dir)
440 {
441 	struct nand_chip *chip = mtd_to_nand(mtd);
442 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
443 	struct dma_async_tx_descriptor *desc;
444 	int flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
445 	int res;
446 
447 	host->dma_slave_config.direction = dir;
448 	host->dma_slave_config.src_addr = dma;
449 	host->dma_slave_config.dst_addr = dma;
450 	host->dma_slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
451 	host->dma_slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
452 	host->dma_slave_config.src_maxburst = 4;
453 	host->dma_slave_config.dst_maxburst = 4;
454 	/* DMA controller does flow control: */
455 	host->dma_slave_config.device_fc = false;
456 	if (dmaengine_slave_config(host->dma_chan, &host->dma_slave_config)) {
457 		dev_err(mtd->dev.parent, "Failed to setup DMA slave\n");
458 		return -ENXIO;
459 	}
460 
461 	sg_init_one(&host->sgl, mem, len);
462 
463 	res = dma_map_sg(host->dma_chan->device->dev, &host->sgl, 1,
464 			 DMA_BIDIRECTIONAL);
465 	if (res != 1) {
466 		dev_err(mtd->dev.parent, "Failed to map sg list\n");
467 		return -ENXIO;
468 	}
469 	desc = dmaengine_prep_slave_sg(host->dma_chan, &host->sgl, 1, dir,
470 				       flags);
471 	if (!desc) {
472 		dev_err(mtd->dev.parent, "Failed to prepare slave sg\n");
473 		goto out1;
474 	}
475 
476 	init_completion(&host->comp);
477 	desc->callback = lpc32xx_dma_complete_func;
478 	desc->callback_param = &host->comp;
479 
480 	dmaengine_submit(desc);
481 	dma_async_issue_pending(host->dma_chan);
482 
483 	wait_for_completion_timeout(&host->comp, msecs_to_jiffies(1000));
484 
485 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
486 		     DMA_BIDIRECTIONAL);
487 
488 	return 0;
489 out1:
490 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
491 		     DMA_BIDIRECTIONAL);
492 	return -ENXIO;
493 }
494 
495 /*
496  * DMA read/write transfers with ECC support
497  */
498 static int lpc32xx_xfer(struct mtd_info *mtd, uint8_t *buf, int eccsubpages,
499 			int read)
500 {
501 	struct nand_chip *chip = mtd_to_nand(mtd);
502 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
503 	int i, status = 0;
504 	unsigned long timeout;
505 	int res;
506 	enum dma_transfer_direction dir =
507 		read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
508 	uint8_t *dma_buf;
509 	bool dma_mapped;
510 
511 	if ((void *)buf <= high_memory) {
512 		dma_buf = buf;
513 		dma_mapped = true;
514 	} else {
515 		dma_buf = host->data_buf;
516 		dma_mapped = false;
517 		if (!read)
518 			memcpy(host->data_buf, buf, mtd->writesize);
519 	}
520 
521 	if (read) {
522 		writel(readl(SLC_CFG(host->io_base)) |
523 		       SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
524 		       SLCCFG_DMA_BURST, SLC_CFG(host->io_base));
525 	} else {
526 		writel((readl(SLC_CFG(host->io_base)) |
527 			SLCCFG_ECC_EN | SLCCFG_DMA_ECC | SLCCFG_DMA_BURST) &
528 		       ~SLCCFG_DMA_DIR,
529 			SLC_CFG(host->io_base));
530 	}
531 
532 	/* Clear initial ECC */
533 	writel(SLCCTRL_ECC_CLEAR, SLC_CTRL(host->io_base));
534 
535 	/* Transfer size is data area only */
536 	writel(mtd->writesize, SLC_TC(host->io_base));
537 
538 	/* Start transfer in the NAND controller */
539 	writel(readl(SLC_CTRL(host->io_base)) | SLCCTRL_DMA_START,
540 	       SLC_CTRL(host->io_base));
541 
542 	for (i = 0; i < chip->ecc.steps; i++) {
543 		/* Data */
544 		res = lpc32xx_xmit_dma(mtd, SLC_DMA_DATA(host->io_base_dma),
545 				       dma_buf + i * chip->ecc.size,
546 				       mtd->writesize / chip->ecc.steps, dir);
547 		if (res)
548 			return res;
549 
550 		/* Always _read_ ECC */
551 		if (i == chip->ecc.steps - 1)
552 			break;
553 		if (!read) /* ECC availability delayed on write */
554 			udelay(10);
555 		res = lpc32xx_xmit_dma(mtd, SLC_ECC(host->io_base_dma),
556 				       &host->ecc_buf[i], 4, DMA_DEV_TO_MEM);
557 		if (res)
558 			return res;
559 	}
560 
561 	/*
562 	 * According to NXP, the DMA can be finished here, but the NAND
563 	 * controller may still have buffered data. After porting to using the
564 	 * dmaengine DMA driver (amba-pl080), the condition (DMA_FIFO empty)
565 	 * appears to be always true, according to tests. Keeping the check for
566 	 * safety reasons for now.
567 	 */
568 	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) {
569 		dev_warn(mtd->dev.parent, "FIFO not empty!\n");
570 		timeout = jiffies + msecs_to_jiffies(LPC32XX_DMA_TIMEOUT);
571 		while ((readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) &&
572 		       time_before(jiffies, timeout))
573 			cpu_relax();
574 		if (!time_before(jiffies, timeout)) {
575 			dev_err(mtd->dev.parent, "FIFO held data too long\n");
576 			status = -EIO;
577 		}
578 	}
579 
580 	/* Read last calculated ECC value */
581 	if (!read)
582 		udelay(10);
583 	host->ecc_buf[chip->ecc.steps - 1] =
584 		readl(SLC_ECC(host->io_base));
585 
586 	/* Flush DMA */
587 	dmaengine_terminate_all(host->dma_chan);
588 
589 	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO ||
590 	    readl(SLC_TC(host->io_base))) {
591 		/* Something is left in the FIFO, something is wrong */
592 		dev_err(mtd->dev.parent, "DMA FIFO failure\n");
593 		status = -EIO;
594 	}
595 
596 	/* Stop DMA & HW ECC */
597 	writel(readl(SLC_CTRL(host->io_base)) & ~SLCCTRL_DMA_START,
598 	       SLC_CTRL(host->io_base));
599 	writel(readl(SLC_CFG(host->io_base)) &
600 	       ~(SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
601 		 SLCCFG_DMA_BURST), SLC_CFG(host->io_base));
602 
603 	if (!dma_mapped && read)
604 		memcpy(buf, host->data_buf, mtd->writesize);
605 
606 	return status;
607 }
608 
609 /*
610  * Read the data and OOB data from the device, use ECC correction with the
611  * data, disable ECC for the OOB data
612  */
613 static int lpc32xx_nand_read_page_syndrome(struct mtd_info *mtd,
614 					   struct nand_chip *chip, uint8_t *buf,
615 					   int oob_required, int page)
616 {
617 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
618 	struct mtd_oob_region oobregion = { };
619 	int stat, i, status, error;
620 	uint8_t *oobecc, tmpecc[LPC32XX_ECC_SAVE_SIZE];
621 
622 	/* Issue read command */
623 	nand_read_page_op(chip, page, 0, NULL, 0);
624 
625 	/* Read data and oob, calculate ECC */
626 	status = lpc32xx_xfer(mtd, buf, chip->ecc.steps, 1);
627 
628 	/* Get OOB data */
629 	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
630 
631 	/* Convert to stored ECC format */
632 	lpc32xx_slc_ecc_copy(tmpecc, (uint32_t *) host->ecc_buf, chip->ecc.steps);
633 
634 	/* Pointer to ECC data retrieved from NAND spare area */
635 	error = mtd_ooblayout_ecc(mtd, 0, &oobregion);
636 	if (error)
637 		return error;
638 
639 	oobecc = chip->oob_poi + oobregion.offset;
640 
641 	for (i = 0; i < chip->ecc.steps; i++) {
642 		stat = chip->ecc.correct(mtd, buf, oobecc,
643 					 &tmpecc[i * chip->ecc.bytes]);
644 		if (stat < 0)
645 			mtd->ecc_stats.failed++;
646 		else
647 			mtd->ecc_stats.corrected += stat;
648 
649 		buf += chip->ecc.size;
650 		oobecc += chip->ecc.bytes;
651 	}
652 
653 	return status;
654 }
655 
656 /*
657  * Read the data and OOB data from the device, no ECC correction with the
658  * data or OOB data
659  */
660 static int lpc32xx_nand_read_page_raw_syndrome(struct mtd_info *mtd,
661 					       struct nand_chip *chip,
662 					       uint8_t *buf, int oob_required,
663 					       int page)
664 {
665 	/* Issue read command */
666 	nand_read_page_op(chip, page, 0, NULL, 0);
667 
668 	/* Raw reads can just use the FIFO interface */
669 	chip->read_buf(mtd, buf, chip->ecc.size * chip->ecc.steps);
670 	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
671 
672 	return 0;
673 }
674 
675 /*
676  * Write the data and OOB data to the device, use ECC with the data,
677  * disable ECC for the OOB data
678  */
679 static int lpc32xx_nand_write_page_syndrome(struct mtd_info *mtd,
680 					    struct nand_chip *chip,
681 					    const uint8_t *buf,
682 					    int oob_required, int page)
683 {
684 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
685 	struct mtd_oob_region oobregion = { };
686 	uint8_t *pb;
687 	int error;
688 
689 	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
690 
691 	/* Write data, calculate ECC on outbound data */
692 	error = lpc32xx_xfer(mtd, (uint8_t *)buf, chip->ecc.steps, 0);
693 	if (error)
694 		return error;
695 
696 	/*
697 	 * The calculated ECC needs some manual work done to it before
698 	 * committing it to NAND. Process the calculated ECC and place
699 	 * the resultant values directly into the OOB buffer. */
700 	error = mtd_ooblayout_ecc(mtd, 0, &oobregion);
701 	if (error)
702 		return error;
703 
704 	pb = chip->oob_poi + oobregion.offset;
705 	lpc32xx_slc_ecc_copy(pb, (uint32_t *)host->ecc_buf, chip->ecc.steps);
706 
707 	/* Write ECC data to device */
708 	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
709 
710 	return nand_prog_page_end_op(chip);
711 }
712 
713 /*
714  * Write the data and OOB data to the device, no ECC correction with the
715  * data or OOB data
716  */
717 static int lpc32xx_nand_write_page_raw_syndrome(struct mtd_info *mtd,
718 						struct nand_chip *chip,
719 						const uint8_t *buf,
720 						int oob_required, int page)
721 {
722 	/* Raw writes can just use the FIFO interface */
723 	nand_prog_page_begin_op(chip, page, 0, buf,
724 				chip->ecc.size * chip->ecc.steps);
725 	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
726 
727 	return nand_prog_page_end_op(chip);
728 }
729 
730 static int lpc32xx_nand_dma_setup(struct lpc32xx_nand_host *host)
731 {
732 	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
733 	dma_cap_mask_t mask;
734 
735 	if (!host->pdata || !host->pdata->dma_filter) {
736 		dev_err(mtd->dev.parent, "no DMA platform data\n");
737 		return -ENOENT;
738 	}
739 
740 	dma_cap_zero(mask);
741 	dma_cap_set(DMA_SLAVE, mask);
742 	host->dma_chan = dma_request_channel(mask, host->pdata->dma_filter,
743 					     "nand-slc");
744 	if (!host->dma_chan) {
745 		dev_err(mtd->dev.parent, "Failed to request DMA channel\n");
746 		return -EBUSY;
747 	}
748 
749 	return 0;
750 }
751 
752 static struct lpc32xx_nand_cfg_slc *lpc32xx_parse_dt(struct device *dev)
753 {
754 	struct lpc32xx_nand_cfg_slc *ncfg;
755 	struct device_node *np = dev->of_node;
756 
757 	ncfg = devm_kzalloc(dev, sizeof(*ncfg), GFP_KERNEL);
758 	if (!ncfg)
759 		return NULL;
760 
761 	of_property_read_u32(np, "nxp,wdr-clks", &ncfg->wdr_clks);
762 	of_property_read_u32(np, "nxp,wwidth", &ncfg->wwidth);
763 	of_property_read_u32(np, "nxp,whold", &ncfg->whold);
764 	of_property_read_u32(np, "nxp,wsetup", &ncfg->wsetup);
765 	of_property_read_u32(np, "nxp,rdr-clks", &ncfg->rdr_clks);
766 	of_property_read_u32(np, "nxp,rwidth", &ncfg->rwidth);
767 	of_property_read_u32(np, "nxp,rhold", &ncfg->rhold);
768 	of_property_read_u32(np, "nxp,rsetup", &ncfg->rsetup);
769 
770 	if (!ncfg->wdr_clks || !ncfg->wwidth || !ncfg->whold ||
771 	    !ncfg->wsetup || !ncfg->rdr_clks || !ncfg->rwidth ||
772 	    !ncfg->rhold || !ncfg->rsetup) {
773 		dev_err(dev, "chip parameters not specified correctly\n");
774 		return NULL;
775 	}
776 
777 	ncfg->wp_gpio = of_get_named_gpio(np, "gpios", 0);
778 
779 	return ncfg;
780 }
781 
782 static int lpc32xx_nand_attach_chip(struct nand_chip *chip)
783 {
784 	struct mtd_info *mtd = nand_to_mtd(chip);
785 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
786 
787 	/* OOB and ECC CPU and DMA work areas */
788 	host->ecc_buf = (uint32_t *)(host->data_buf + LPC32XX_DMA_DATA_SIZE);
789 
790 	/*
791 	 * Small page FLASH has a unique OOB layout, but large and huge
792 	 * page FLASH use the standard layout. Small page FLASH uses a
793 	 * custom BBT marker layout.
794 	 */
795 	if (mtd->writesize <= 512)
796 		mtd_set_ooblayout(mtd, &lpc32xx_ooblayout_ops);
797 
798 	/* These sizes remain the same regardless of page size */
799 	chip->ecc.size = 256;
800 	chip->ecc.bytes = LPC32XX_SLC_DEV_ECC_BYTES;
801 	chip->ecc.prepad = 0;
802 	chip->ecc.postpad = 0;
803 
804 	/*
805 	 * Use a custom BBT marker setup for small page FLASH that
806 	 * won't interfere with the ECC layout. Large and huge page
807 	 * FLASH use the standard layout.
808 	 */
809 	if ((chip->bbt_options & NAND_BBT_USE_FLASH) &&
810 	    mtd->writesize <= 512) {
811 		chip->bbt_td = &bbt_smallpage_main_descr;
812 		chip->bbt_md = &bbt_smallpage_mirror_descr;
813 	}
814 
815 	return 0;
816 }
817 
818 static const struct nand_controller_ops lpc32xx_nand_controller_ops = {
819 	.attach_chip = lpc32xx_nand_attach_chip,
820 };
821 
822 /*
823  * Probe for NAND controller
824  */
825 static int lpc32xx_nand_probe(struct platform_device *pdev)
826 {
827 	struct lpc32xx_nand_host *host;
828 	struct mtd_info *mtd;
829 	struct nand_chip *chip;
830 	struct resource *rc;
831 	int res;
832 
833 	/* Allocate memory for the device structure (and zero it) */
834 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
835 	if (!host)
836 		return -ENOMEM;
837 
838 	rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
839 	host->io_base = devm_ioremap_resource(&pdev->dev, rc);
840 	if (IS_ERR(host->io_base))
841 		return PTR_ERR(host->io_base);
842 
843 	host->io_base_dma = rc->start;
844 	if (pdev->dev.of_node)
845 		host->ncfg = lpc32xx_parse_dt(&pdev->dev);
846 	if (!host->ncfg) {
847 		dev_err(&pdev->dev,
848 			"Missing or bad NAND config from device tree\n");
849 		return -ENOENT;
850 	}
851 	if (host->ncfg->wp_gpio == -EPROBE_DEFER)
852 		return -EPROBE_DEFER;
853 	if (gpio_is_valid(host->ncfg->wp_gpio) && devm_gpio_request(&pdev->dev,
854 			host->ncfg->wp_gpio, "NAND WP")) {
855 		dev_err(&pdev->dev, "GPIO not available\n");
856 		return -EBUSY;
857 	}
858 	lpc32xx_wp_disable(host);
859 
860 	host->pdata = dev_get_platdata(&pdev->dev);
861 
862 	chip = &host->nand_chip;
863 	mtd = nand_to_mtd(chip);
864 	nand_set_controller_data(chip, host);
865 	nand_set_flash_node(chip, pdev->dev.of_node);
866 	mtd->owner = THIS_MODULE;
867 	mtd->dev.parent = &pdev->dev;
868 
869 	/* Get NAND clock */
870 	host->clk = devm_clk_get(&pdev->dev, NULL);
871 	if (IS_ERR(host->clk)) {
872 		dev_err(&pdev->dev, "Clock failure\n");
873 		res = -ENOENT;
874 		goto enable_wp;
875 	}
876 	res = clk_prepare_enable(host->clk);
877 	if (res)
878 		goto enable_wp;
879 
880 	/* Set NAND IO addresses and command/ready functions */
881 	chip->IO_ADDR_R = SLC_DATA(host->io_base);
882 	chip->IO_ADDR_W = SLC_DATA(host->io_base);
883 	chip->cmd_ctrl = lpc32xx_nand_cmd_ctrl;
884 	chip->dev_ready = lpc32xx_nand_device_ready;
885 	chip->chip_delay = 20; /* 20us command delay time */
886 
887 	/* Init NAND controller */
888 	lpc32xx_nand_setup(host);
889 
890 	platform_set_drvdata(pdev, host);
891 
892 	/* NAND callbacks for LPC32xx SLC hardware */
893 	chip->ecc.mode = NAND_ECC_HW_SYNDROME;
894 	chip->read_byte = lpc32xx_nand_read_byte;
895 	chip->read_buf = lpc32xx_nand_read_buf;
896 	chip->write_buf = lpc32xx_nand_write_buf;
897 	chip->ecc.read_page_raw = lpc32xx_nand_read_page_raw_syndrome;
898 	chip->ecc.read_page = lpc32xx_nand_read_page_syndrome;
899 	chip->ecc.write_page_raw = lpc32xx_nand_write_page_raw_syndrome;
900 	chip->ecc.write_page = lpc32xx_nand_write_page_syndrome;
901 	chip->ecc.write_oob = lpc32xx_nand_write_oob_syndrome;
902 	chip->ecc.read_oob = lpc32xx_nand_read_oob_syndrome;
903 	chip->ecc.calculate = lpc32xx_nand_ecc_calculate;
904 	chip->ecc.correct = nand_correct_data;
905 	chip->ecc.strength = 1;
906 	chip->ecc.hwctl = lpc32xx_nand_ecc_enable;
907 
908 	/*
909 	 * Allocate a large enough buffer for a single huge page plus
910 	 * extra space for the spare area and ECC storage area
911 	 */
912 	host->dma_buf_len = LPC32XX_DMA_DATA_SIZE + LPC32XX_ECC_SAVE_SIZE;
913 	host->data_buf = devm_kzalloc(&pdev->dev, host->dma_buf_len,
914 				      GFP_KERNEL);
915 	if (host->data_buf == NULL) {
916 		res = -ENOMEM;
917 		goto unprepare_clk;
918 	}
919 
920 	res = lpc32xx_nand_dma_setup(host);
921 	if (res) {
922 		res = -EIO;
923 		goto unprepare_clk;
924 	}
925 
926 	/* Find NAND device */
927 	chip->dummy_controller.ops = &lpc32xx_nand_controller_ops;
928 	res = nand_scan(mtd, 1);
929 	if (res)
930 		goto release_dma;
931 
932 	mtd->name = "nxp_lpc3220_slc";
933 	res = mtd_device_register(mtd, host->ncfg->parts,
934 				  host->ncfg->num_parts);
935 	if (res)
936 		goto cleanup_nand;
937 
938 	return 0;
939 
940 cleanup_nand:
941 	nand_cleanup(chip);
942 release_dma:
943 	dma_release_channel(host->dma_chan);
944 unprepare_clk:
945 	clk_disable_unprepare(host->clk);
946 enable_wp:
947 	lpc32xx_wp_enable(host);
948 
949 	return res;
950 }
951 
952 /*
953  * Remove NAND device.
954  */
955 static int lpc32xx_nand_remove(struct platform_device *pdev)
956 {
957 	uint32_t tmp;
958 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
959 	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
960 
961 	nand_release(mtd);
962 	dma_release_channel(host->dma_chan);
963 
964 	/* Force CE high */
965 	tmp = readl(SLC_CTRL(host->io_base));
966 	tmp &= ~SLCCFG_CE_LOW;
967 	writel(tmp, SLC_CTRL(host->io_base));
968 
969 	clk_disable_unprepare(host->clk);
970 	lpc32xx_wp_enable(host);
971 
972 	return 0;
973 }
974 
975 #ifdef CONFIG_PM
976 static int lpc32xx_nand_resume(struct platform_device *pdev)
977 {
978 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
979 	int ret;
980 
981 	/* Re-enable NAND clock */
982 	ret = clk_prepare_enable(host->clk);
983 	if (ret)
984 		return ret;
985 
986 	/* Fresh init of NAND controller */
987 	lpc32xx_nand_setup(host);
988 
989 	/* Disable write protect */
990 	lpc32xx_wp_disable(host);
991 
992 	return 0;
993 }
994 
995 static int lpc32xx_nand_suspend(struct platform_device *pdev, pm_message_t pm)
996 {
997 	uint32_t tmp;
998 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
999 
1000 	/* Force CE high */
1001 	tmp = readl(SLC_CTRL(host->io_base));
1002 	tmp &= ~SLCCFG_CE_LOW;
1003 	writel(tmp, SLC_CTRL(host->io_base));
1004 
1005 	/* Enable write protect for safety */
1006 	lpc32xx_wp_enable(host);
1007 
1008 	/* Disable clock */
1009 	clk_disable_unprepare(host->clk);
1010 
1011 	return 0;
1012 }
1013 
1014 #else
1015 #define lpc32xx_nand_resume NULL
1016 #define lpc32xx_nand_suspend NULL
1017 #endif
1018 
1019 static const struct of_device_id lpc32xx_nand_match[] = {
1020 	{ .compatible = "nxp,lpc3220-slc" },
1021 	{ /* sentinel */ },
1022 };
1023 MODULE_DEVICE_TABLE(of, lpc32xx_nand_match);
1024 
1025 static struct platform_driver lpc32xx_nand_driver = {
1026 	.probe		= lpc32xx_nand_probe,
1027 	.remove		= lpc32xx_nand_remove,
1028 	.resume		= lpc32xx_nand_resume,
1029 	.suspend	= lpc32xx_nand_suspend,
1030 	.driver		= {
1031 		.name	= LPC32XX_MODNAME,
1032 		.of_match_table = lpc32xx_nand_match,
1033 	},
1034 };
1035 
1036 module_platform_driver(lpc32xx_nand_driver);
1037 
1038 MODULE_LICENSE("GPL");
1039 MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
1040 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
1041 MODULE_DESCRIPTION("NAND driver for the NXP LPC32XX SLC controller");
1042