xref: /linux/drivers/mtd/nand/raw/lpc32xx_slc.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * NXP LPC32XX NAND SLC driver
4  *
5  * Authors:
6  *    Kevin Wells <kevin.wells@nxp.com>
7  *    Roland Stigge <stigge@antcom.de>
8  *
9  * Copyright © 2011 NXP Semiconductors
10  * Copyright © 2012 Roland Stigge
11  */
12 
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/rawnand.h>
18 #include <linux/mtd/partitions.h>
19 #include <linux/clk.h>
20 #include <linux/err.h>
21 #include <linux/delay.h>
22 #include <linux/io.h>
23 #include <linux/mm.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/dmaengine.h>
26 #include <linux/gpio/consumer.h>
27 #include <linux/of.h>
28 #include <linux/mtd/lpc32xx_slc.h>
29 
30 #define LPC32XX_MODNAME		"lpc32xx-nand"
31 
32 /**********************************************************************
33 * SLC NAND controller register offsets
34 **********************************************************************/
35 
36 #define SLC_DATA(x)		(x + 0x000)
37 #define SLC_ADDR(x)		(x + 0x004)
38 #define SLC_CMD(x)		(x + 0x008)
39 #define SLC_STOP(x)		(x + 0x00C)
40 #define SLC_CTRL(x)		(x + 0x010)
41 #define SLC_CFG(x)		(x + 0x014)
42 #define SLC_STAT(x)		(x + 0x018)
43 #define SLC_INT_STAT(x)		(x + 0x01C)
44 #define SLC_IEN(x)		(x + 0x020)
45 #define SLC_ISR(x)		(x + 0x024)
46 #define SLC_ICR(x)		(x + 0x028)
47 #define SLC_TAC(x)		(x + 0x02C)
48 #define SLC_TC(x)		(x + 0x030)
49 #define SLC_ECC(x)		(x + 0x034)
50 #define SLC_DMA_DATA(x)		(x + 0x038)
51 
52 /**********************************************************************
53 * slc_ctrl register definitions
54 **********************************************************************/
55 #define SLCCTRL_SW_RESET	(1 << 2) /* Reset the NAND controller bit */
56 #define SLCCTRL_ECC_CLEAR	(1 << 1) /* Reset ECC bit */
57 #define SLCCTRL_DMA_START	(1 << 0) /* Start DMA channel bit */
58 
59 /**********************************************************************
60 * slc_cfg register definitions
61 **********************************************************************/
62 #define SLCCFG_CE_LOW		(1 << 5) /* Force CE low bit */
63 #define SLCCFG_DMA_ECC		(1 << 4) /* Enable DMA ECC bit */
64 #define SLCCFG_ECC_EN		(1 << 3) /* ECC enable bit */
65 #define SLCCFG_DMA_BURST	(1 << 2) /* DMA burst bit */
66 #define SLCCFG_DMA_DIR		(1 << 1) /* DMA write(0)/read(1) bit */
67 #define SLCCFG_WIDTH		(1 << 0) /* External device width, 0=8bit */
68 
69 /**********************************************************************
70 * slc_stat register definitions
71 **********************************************************************/
72 #define SLCSTAT_DMA_FIFO	(1 << 2) /* DMA FIFO has data bit */
73 #define SLCSTAT_SLC_FIFO	(1 << 1) /* SLC FIFO has data bit */
74 #define SLCSTAT_NAND_READY	(1 << 0) /* NAND device is ready bit */
75 
76 /**********************************************************************
77 * slc_int_stat, slc_ien, slc_isr, and slc_icr register definitions
78 **********************************************************************/
79 #define SLCSTAT_INT_TC		(1 << 1) /* Transfer count bit */
80 #define SLCSTAT_INT_RDY_EN	(1 << 0) /* Ready interrupt bit */
81 
82 /**********************************************************************
83 * slc_tac register definitions
84 **********************************************************************/
85 /* Computation of clock cycles on basis of controller and device clock rates */
86 #define SLCTAC_CLOCKS(c, n, s)	(min_t(u32, DIV_ROUND_UP(c, n) - 1, 0xF) << s)
87 
88 /* Clock setting for RDY write sample wait time in 2*n clocks */
89 #define SLCTAC_WDR(n)		(((n) & 0xF) << 28)
90 /* Write pulse width in clock cycles, 1 to 16 clocks */
91 #define SLCTAC_WWIDTH(c, n)	(SLCTAC_CLOCKS(c, n, 24))
92 /* Write hold time of control and data signals, 1 to 16 clocks */
93 #define SLCTAC_WHOLD(c, n)	(SLCTAC_CLOCKS(c, n, 20))
94 /* Write setup time of control and data signals, 1 to 16 clocks */
95 #define SLCTAC_WSETUP(c, n)	(SLCTAC_CLOCKS(c, n, 16))
96 /* Clock setting for RDY read sample wait time in 2*n clocks */
97 #define SLCTAC_RDR(n)		(((n) & 0xF) << 12)
98 /* Read pulse width in clock cycles, 1 to 16 clocks */
99 #define SLCTAC_RWIDTH(c, n)	(SLCTAC_CLOCKS(c, n, 8))
100 /* Read hold time of control and data signals, 1 to 16 clocks */
101 #define SLCTAC_RHOLD(c, n)	(SLCTAC_CLOCKS(c, n, 4))
102 /* Read setup time of control and data signals, 1 to 16 clocks */
103 #define SLCTAC_RSETUP(c, n)	(SLCTAC_CLOCKS(c, n, 0))
104 
105 /**********************************************************************
106 * slc_ecc register definitions
107 **********************************************************************/
108 /* ECC line party fetch macro */
109 #define SLCECC_TO_LINEPAR(n)	(((n) >> 6) & 0x7FFF)
110 #define SLCECC_TO_COLPAR(n)	((n) & 0x3F)
111 
112 /*
113  * DMA requires storage space for the DMA local buffer and the hardware ECC
114  * storage area. The DMA local buffer is only used if DMA mapping fails
115  * during runtime.
116  */
117 #define LPC32XX_DMA_DATA_SIZE		4096
118 #define LPC32XX_ECC_SAVE_SIZE		((4096 / 256) * 4)
119 
120 /* Number of bytes used for ECC stored in NAND per 256 bytes */
121 #define LPC32XX_SLC_DEV_ECC_BYTES	3
122 
123 /*
124  * If the NAND base clock frequency can't be fetched, this frequency will be
125  * used instead as the base. This rate is used to setup the timing registers
126  * used for NAND accesses.
127  */
128 #define LPC32XX_DEF_BUS_RATE		133250000
129 
130 /* Milliseconds for DMA FIFO timeout (unlikely anyway) */
131 #define LPC32XX_DMA_TIMEOUT		100
132 
133 /*
134  * NAND ECC Layout for small page NAND devices
135  * Note: For large and huge page devices, the default layouts are used
136  */
137 static int lpc32xx_ooblayout_ecc(struct mtd_info *mtd, int section,
138 				 struct mtd_oob_region *oobregion)
139 {
140 	if (section)
141 		return -ERANGE;
142 
143 	oobregion->length = 6;
144 	oobregion->offset = 10;
145 
146 	return 0;
147 }
148 
149 static int lpc32xx_ooblayout_free(struct mtd_info *mtd, int section,
150 				  struct mtd_oob_region *oobregion)
151 {
152 	if (section > 1)
153 		return -ERANGE;
154 
155 	if (!section) {
156 		oobregion->offset = 0;
157 		oobregion->length = 4;
158 	} else {
159 		oobregion->offset = 6;
160 		oobregion->length = 4;
161 	}
162 
163 	return 0;
164 }
165 
166 static const struct mtd_ooblayout_ops lpc32xx_ooblayout_ops = {
167 	.ecc = lpc32xx_ooblayout_ecc,
168 	.free = lpc32xx_ooblayout_free,
169 };
170 
171 static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
172 static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
173 
174 /*
175  * Small page FLASH BBT descriptors, marker at offset 0, version at offset 6
176  * Note: Large page devices used the default layout
177  */
178 static struct nand_bbt_descr bbt_smallpage_main_descr = {
179 	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
180 		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
181 	.offs =	0,
182 	.len = 4,
183 	.veroffs = 6,
184 	.maxblocks = 4,
185 	.pattern = bbt_pattern
186 };
187 
188 static struct nand_bbt_descr bbt_smallpage_mirror_descr = {
189 	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
190 		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
191 	.offs =	0,
192 	.len = 4,
193 	.veroffs = 6,
194 	.maxblocks = 4,
195 	.pattern = mirror_pattern
196 };
197 
198 /*
199  * NAND platform configuration structure
200  */
201 struct lpc32xx_nand_cfg_slc {
202 	uint32_t wdr_clks;
203 	uint32_t wwidth;
204 	uint32_t whold;
205 	uint32_t wsetup;
206 	uint32_t rdr_clks;
207 	uint32_t rwidth;
208 	uint32_t rhold;
209 	uint32_t rsetup;
210 	struct mtd_partition *parts;
211 	unsigned num_parts;
212 };
213 
214 struct lpc32xx_nand_host {
215 	struct nand_chip	nand_chip;
216 	struct lpc32xx_slc_platform_data *pdata;
217 	struct clk		*clk;
218 	struct gpio_desc	*wp_gpio;
219 	void __iomem		*io_base;
220 	struct lpc32xx_nand_cfg_slc *ncfg;
221 
222 	struct completion	comp;
223 	struct dma_chan		*dma_chan;
224 	uint32_t		dma_buf_len;
225 	struct dma_slave_config	dma_slave_config;
226 	struct scatterlist	sgl;
227 
228 	/*
229 	 * DMA and CPU addresses of ECC work area and data buffer
230 	 */
231 	uint32_t		*ecc_buf;
232 	uint8_t			*data_buf;
233 	dma_addr_t		io_base_dma;
234 };
235 
236 static void lpc32xx_nand_setup(struct lpc32xx_nand_host *host)
237 {
238 	uint32_t clkrate, tmp;
239 
240 	/* Reset SLC controller */
241 	writel(SLCCTRL_SW_RESET, SLC_CTRL(host->io_base));
242 	udelay(1000);
243 
244 	/* Basic setup */
245 	writel(0, SLC_CFG(host->io_base));
246 	writel(0, SLC_IEN(host->io_base));
247 	writel((SLCSTAT_INT_TC | SLCSTAT_INT_RDY_EN),
248 		SLC_ICR(host->io_base));
249 
250 	/* Get base clock for SLC block */
251 	clkrate = clk_get_rate(host->clk);
252 	if (clkrate == 0)
253 		clkrate = LPC32XX_DEF_BUS_RATE;
254 
255 	/* Compute clock setup values */
256 	tmp = SLCTAC_WDR(host->ncfg->wdr_clks) |
257 		SLCTAC_WWIDTH(clkrate, host->ncfg->wwidth) |
258 		SLCTAC_WHOLD(clkrate, host->ncfg->whold) |
259 		SLCTAC_WSETUP(clkrate, host->ncfg->wsetup) |
260 		SLCTAC_RDR(host->ncfg->rdr_clks) |
261 		SLCTAC_RWIDTH(clkrate, host->ncfg->rwidth) |
262 		SLCTAC_RHOLD(clkrate, host->ncfg->rhold) |
263 		SLCTAC_RSETUP(clkrate, host->ncfg->rsetup);
264 	writel(tmp, SLC_TAC(host->io_base));
265 }
266 
267 /*
268  * Hardware specific access to control lines
269  */
270 static void lpc32xx_nand_cmd_ctrl(struct nand_chip *chip, int cmd,
271 				  unsigned int ctrl)
272 {
273 	uint32_t tmp;
274 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
275 
276 	/* Does CE state need to be changed? */
277 	tmp = readl(SLC_CFG(host->io_base));
278 	if (ctrl & NAND_NCE)
279 		tmp |= SLCCFG_CE_LOW;
280 	else
281 		tmp &= ~SLCCFG_CE_LOW;
282 	writel(tmp, SLC_CFG(host->io_base));
283 
284 	if (cmd != NAND_CMD_NONE) {
285 		if (ctrl & NAND_CLE)
286 			writel(cmd, SLC_CMD(host->io_base));
287 		else
288 			writel(cmd, SLC_ADDR(host->io_base));
289 	}
290 }
291 
292 /*
293  * Read the Device Ready pin
294  */
295 static int lpc32xx_nand_device_ready(struct nand_chip *chip)
296 {
297 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
298 	int rdy = 0;
299 
300 	if ((readl(SLC_STAT(host->io_base)) & SLCSTAT_NAND_READY) != 0)
301 		rdy = 1;
302 
303 	return rdy;
304 }
305 
306 /*
307  * Enable NAND write protect
308  */
309 static void lpc32xx_wp_enable(struct lpc32xx_nand_host *host)
310 {
311 	if (host->wp_gpio)
312 		gpiod_set_value_cansleep(host->wp_gpio, 1);
313 }
314 
315 /*
316  * Disable NAND write protect
317  */
318 static void lpc32xx_wp_disable(struct lpc32xx_nand_host *host)
319 {
320 	if (host->wp_gpio)
321 		gpiod_set_value_cansleep(host->wp_gpio, 0);
322 }
323 
324 /*
325  * Prepares SLC for transfers with H/W ECC enabled
326  */
327 static void lpc32xx_nand_ecc_enable(struct nand_chip *chip, int mode)
328 {
329 	/* Hardware ECC is enabled automatically in hardware as needed */
330 }
331 
332 /*
333  * Calculates the ECC for the data
334  */
335 static int lpc32xx_nand_ecc_calculate(struct nand_chip *chip,
336 				      const unsigned char *buf,
337 				      unsigned char *code)
338 {
339 	/*
340 	 * ECC is calculated automatically in hardware during syndrome read
341 	 * and write operations, so it doesn't need to be calculated here.
342 	 */
343 	return 0;
344 }
345 
346 /*
347  * Read a single byte from NAND device
348  */
349 static uint8_t lpc32xx_nand_read_byte(struct nand_chip *chip)
350 {
351 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
352 
353 	return (uint8_t)readl(SLC_DATA(host->io_base));
354 }
355 
356 /*
357  * Simple device read without ECC
358  */
359 static void lpc32xx_nand_read_buf(struct nand_chip *chip, u_char *buf, int len)
360 {
361 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
362 
363 	/* Direct device read with no ECC */
364 	while (len-- > 0)
365 		*buf++ = (uint8_t)readl(SLC_DATA(host->io_base));
366 }
367 
368 /*
369  * Simple device write without ECC
370  */
371 static void lpc32xx_nand_write_buf(struct nand_chip *chip, const uint8_t *buf,
372 				   int len)
373 {
374 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
375 
376 	/* Direct device write with no ECC */
377 	while (len-- > 0)
378 		writel((uint32_t)*buf++, SLC_DATA(host->io_base));
379 }
380 
381 /*
382  * Read the OOB data from the device without ECC using FIFO method
383  */
384 static int lpc32xx_nand_read_oob_syndrome(struct nand_chip *chip, int page)
385 {
386 	struct mtd_info *mtd = nand_to_mtd(chip);
387 
388 	return nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
389 }
390 
391 /*
392  * Write the OOB data to the device without ECC using FIFO method
393  */
394 static int lpc32xx_nand_write_oob_syndrome(struct nand_chip *chip, int page)
395 {
396 	struct mtd_info *mtd = nand_to_mtd(chip);
397 
398 	return nand_prog_page_op(chip, page, mtd->writesize, chip->oob_poi,
399 				 mtd->oobsize);
400 }
401 
402 /*
403  * Fills in the ECC fields in the OOB buffer with the hardware generated ECC
404  */
405 static void lpc32xx_slc_ecc_copy(uint8_t *spare, const uint32_t *ecc, int count)
406 {
407 	int i;
408 
409 	for (i = 0; i < (count * 3); i += 3) {
410 		uint32_t ce = ecc[i / 3];
411 		ce = ~(ce << 2) & 0xFFFFFF;
412 		spare[i + 2] = (uint8_t)(ce & 0xFF);
413 		ce >>= 8;
414 		spare[i + 1] = (uint8_t)(ce & 0xFF);
415 		ce >>= 8;
416 		spare[i] = (uint8_t)(ce & 0xFF);
417 	}
418 }
419 
420 static void lpc32xx_dma_complete_func(void *completion)
421 {
422 	complete(completion);
423 }
424 
425 static int lpc32xx_xmit_dma(struct mtd_info *mtd, dma_addr_t dma,
426 			    void *mem, int len, enum dma_transfer_direction dir)
427 {
428 	struct nand_chip *chip = mtd_to_nand(mtd);
429 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
430 	struct dma_async_tx_descriptor *desc;
431 	int flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
432 	int res;
433 
434 	host->dma_slave_config.direction = dir;
435 	host->dma_slave_config.src_addr = dma;
436 	host->dma_slave_config.dst_addr = dma;
437 	host->dma_slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
438 	host->dma_slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
439 	host->dma_slave_config.src_maxburst = 4;
440 	host->dma_slave_config.dst_maxburst = 4;
441 	/* DMA controller does flow control: */
442 	host->dma_slave_config.device_fc = false;
443 	if (dmaengine_slave_config(host->dma_chan, &host->dma_slave_config)) {
444 		dev_err(mtd->dev.parent, "Failed to setup DMA slave\n");
445 		return -ENXIO;
446 	}
447 
448 	sg_init_one(&host->sgl, mem, len);
449 
450 	res = dma_map_sg(host->dma_chan->device->dev, &host->sgl, 1,
451 			 DMA_BIDIRECTIONAL);
452 	if (res != 1) {
453 		dev_err(mtd->dev.parent, "Failed to map sg list\n");
454 		return -ENXIO;
455 	}
456 	desc = dmaengine_prep_slave_sg(host->dma_chan, &host->sgl, 1, dir,
457 				       flags);
458 	if (!desc) {
459 		dev_err(mtd->dev.parent, "Failed to prepare slave sg\n");
460 		goto out1;
461 	}
462 
463 	init_completion(&host->comp);
464 	desc->callback = lpc32xx_dma_complete_func;
465 	desc->callback_param = &host->comp;
466 
467 	dmaengine_submit(desc);
468 	dma_async_issue_pending(host->dma_chan);
469 
470 	wait_for_completion_timeout(&host->comp, msecs_to_jiffies(1000));
471 
472 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
473 		     DMA_BIDIRECTIONAL);
474 
475 	return 0;
476 out1:
477 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
478 		     DMA_BIDIRECTIONAL);
479 	return -ENXIO;
480 }
481 
482 /*
483  * DMA read/write transfers with ECC support
484  */
485 static int lpc32xx_xfer(struct mtd_info *mtd, uint8_t *buf, int eccsubpages,
486 			int read)
487 {
488 	struct nand_chip *chip = mtd_to_nand(mtd);
489 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
490 	int i, status = 0;
491 	unsigned long timeout;
492 	int res;
493 	enum dma_transfer_direction dir =
494 		read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
495 	uint8_t *dma_buf;
496 	bool dma_mapped;
497 
498 	if ((void *)buf <= high_memory) {
499 		dma_buf = buf;
500 		dma_mapped = true;
501 	} else {
502 		dma_buf = host->data_buf;
503 		dma_mapped = false;
504 		if (!read)
505 			memcpy(host->data_buf, buf, mtd->writesize);
506 	}
507 
508 	if (read) {
509 		writel(readl(SLC_CFG(host->io_base)) |
510 		       SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
511 		       SLCCFG_DMA_BURST, SLC_CFG(host->io_base));
512 	} else {
513 		writel((readl(SLC_CFG(host->io_base)) |
514 			SLCCFG_ECC_EN | SLCCFG_DMA_ECC | SLCCFG_DMA_BURST) &
515 		       ~SLCCFG_DMA_DIR,
516 			SLC_CFG(host->io_base));
517 	}
518 
519 	/* Clear initial ECC */
520 	writel(SLCCTRL_ECC_CLEAR, SLC_CTRL(host->io_base));
521 
522 	/* Transfer size is data area only */
523 	writel(mtd->writesize, SLC_TC(host->io_base));
524 
525 	/* Start transfer in the NAND controller */
526 	writel(readl(SLC_CTRL(host->io_base)) | SLCCTRL_DMA_START,
527 	       SLC_CTRL(host->io_base));
528 
529 	for (i = 0; i < chip->ecc.steps; i++) {
530 		/* Data */
531 		res = lpc32xx_xmit_dma(mtd, SLC_DMA_DATA(host->io_base_dma),
532 				       dma_buf + i * chip->ecc.size,
533 				       mtd->writesize / chip->ecc.steps, dir);
534 		if (res)
535 			return res;
536 
537 		/* Always _read_ ECC */
538 		if (i == chip->ecc.steps - 1)
539 			break;
540 		if (!read) /* ECC availability delayed on write */
541 			udelay(10);
542 		res = lpc32xx_xmit_dma(mtd, SLC_ECC(host->io_base_dma),
543 				       &host->ecc_buf[i], 4, DMA_DEV_TO_MEM);
544 		if (res)
545 			return res;
546 	}
547 
548 	/*
549 	 * According to NXP, the DMA can be finished here, but the NAND
550 	 * controller may still have buffered data. After porting to using the
551 	 * dmaengine DMA driver (amba-pl080), the condition (DMA_FIFO empty)
552 	 * appears to be always true, according to tests. Keeping the check for
553 	 * safety reasons for now.
554 	 */
555 	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) {
556 		dev_warn(mtd->dev.parent, "FIFO not empty!\n");
557 		timeout = jiffies + msecs_to_jiffies(LPC32XX_DMA_TIMEOUT);
558 		while ((readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) &&
559 		       time_before(jiffies, timeout))
560 			cpu_relax();
561 		if (!time_before(jiffies, timeout)) {
562 			dev_err(mtd->dev.parent, "FIFO held data too long\n");
563 			status = -EIO;
564 		}
565 	}
566 
567 	/* Read last calculated ECC value */
568 	if (!read)
569 		udelay(10);
570 	host->ecc_buf[chip->ecc.steps - 1] =
571 		readl(SLC_ECC(host->io_base));
572 
573 	/* Flush DMA */
574 	dmaengine_terminate_all(host->dma_chan);
575 
576 	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO ||
577 	    readl(SLC_TC(host->io_base))) {
578 		/* Something is left in the FIFO, something is wrong */
579 		dev_err(mtd->dev.parent, "DMA FIFO failure\n");
580 		status = -EIO;
581 	}
582 
583 	/* Stop DMA & HW ECC */
584 	writel(readl(SLC_CTRL(host->io_base)) & ~SLCCTRL_DMA_START,
585 	       SLC_CTRL(host->io_base));
586 	writel(readl(SLC_CFG(host->io_base)) &
587 	       ~(SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
588 		 SLCCFG_DMA_BURST), SLC_CFG(host->io_base));
589 
590 	if (!dma_mapped && read)
591 		memcpy(buf, host->data_buf, mtd->writesize);
592 
593 	return status;
594 }
595 
596 /*
597  * Read the data and OOB data from the device, use ECC correction with the
598  * data, disable ECC for the OOB data
599  */
600 static int lpc32xx_nand_read_page_syndrome(struct nand_chip *chip, uint8_t *buf,
601 					   int oob_required, int page)
602 {
603 	struct mtd_info *mtd = nand_to_mtd(chip);
604 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
605 	struct mtd_oob_region oobregion = { };
606 	int stat, i, status, error;
607 	uint8_t *oobecc, tmpecc[LPC32XX_ECC_SAVE_SIZE];
608 
609 	/* Issue read command */
610 	nand_read_page_op(chip, page, 0, NULL, 0);
611 
612 	/* Read data and oob, calculate ECC */
613 	status = lpc32xx_xfer(mtd, buf, chip->ecc.steps, 1);
614 
615 	/* Get OOB data */
616 	chip->legacy.read_buf(chip, chip->oob_poi, mtd->oobsize);
617 
618 	/* Convert to stored ECC format */
619 	lpc32xx_slc_ecc_copy(tmpecc, (uint32_t *) host->ecc_buf, chip->ecc.steps);
620 
621 	/* Pointer to ECC data retrieved from NAND spare area */
622 	error = mtd_ooblayout_ecc(mtd, 0, &oobregion);
623 	if (error)
624 		return error;
625 
626 	oobecc = chip->oob_poi + oobregion.offset;
627 
628 	for (i = 0; i < chip->ecc.steps; i++) {
629 		stat = chip->ecc.correct(chip, buf, oobecc,
630 					 &tmpecc[i * chip->ecc.bytes]);
631 		if (stat < 0)
632 			mtd->ecc_stats.failed++;
633 		else
634 			mtd->ecc_stats.corrected += stat;
635 
636 		buf += chip->ecc.size;
637 		oobecc += chip->ecc.bytes;
638 	}
639 
640 	return status;
641 }
642 
643 /*
644  * Read the data and OOB data from the device, no ECC correction with the
645  * data or OOB data
646  */
647 static int lpc32xx_nand_read_page_raw_syndrome(struct nand_chip *chip,
648 					       uint8_t *buf, int oob_required,
649 					       int page)
650 {
651 	struct mtd_info *mtd = nand_to_mtd(chip);
652 
653 	/* Issue read command */
654 	nand_read_page_op(chip, page, 0, NULL, 0);
655 
656 	/* Raw reads can just use the FIFO interface */
657 	chip->legacy.read_buf(chip, buf, chip->ecc.size * chip->ecc.steps);
658 	chip->legacy.read_buf(chip, chip->oob_poi, mtd->oobsize);
659 
660 	return 0;
661 }
662 
663 /*
664  * Write the data and OOB data to the device, use ECC with the data,
665  * disable ECC for the OOB data
666  */
667 static int lpc32xx_nand_write_page_syndrome(struct nand_chip *chip,
668 					    const uint8_t *buf,
669 					    int oob_required, int page)
670 {
671 	struct mtd_info *mtd = nand_to_mtd(chip);
672 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
673 	struct mtd_oob_region oobregion = { };
674 	uint8_t *pb;
675 	int error;
676 
677 	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
678 
679 	/* Write data, calculate ECC on outbound data */
680 	error = lpc32xx_xfer(mtd, (uint8_t *)buf, chip->ecc.steps, 0);
681 	if (error)
682 		return error;
683 
684 	/*
685 	 * The calculated ECC needs some manual work done to it before
686 	 * committing it to NAND. Process the calculated ECC and place
687 	 * the resultant values directly into the OOB buffer. */
688 	error = mtd_ooblayout_ecc(mtd, 0, &oobregion);
689 	if (error)
690 		return error;
691 
692 	pb = chip->oob_poi + oobregion.offset;
693 	lpc32xx_slc_ecc_copy(pb, (uint32_t *)host->ecc_buf, chip->ecc.steps);
694 
695 	/* Write ECC data to device */
696 	chip->legacy.write_buf(chip, chip->oob_poi, mtd->oobsize);
697 
698 	return nand_prog_page_end_op(chip);
699 }
700 
701 /*
702  * Write the data and OOB data to the device, no ECC correction with the
703  * data or OOB data
704  */
705 static int lpc32xx_nand_write_page_raw_syndrome(struct nand_chip *chip,
706 						const uint8_t *buf,
707 						int oob_required, int page)
708 {
709 	struct mtd_info *mtd = nand_to_mtd(chip);
710 
711 	/* Raw writes can just use the FIFO interface */
712 	nand_prog_page_begin_op(chip, page, 0, buf,
713 				chip->ecc.size * chip->ecc.steps);
714 	chip->legacy.write_buf(chip, chip->oob_poi, mtd->oobsize);
715 
716 	return nand_prog_page_end_op(chip);
717 }
718 
719 static int lpc32xx_nand_dma_setup(struct lpc32xx_nand_host *host)
720 {
721 	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
722 	dma_cap_mask_t mask;
723 
724 	host->dma_chan = dma_request_chan(mtd->dev.parent, "rx-tx");
725 	if (IS_ERR(host->dma_chan)) {
726 		/* fallback to request using platform data */
727 		if (!host->pdata || !host->pdata->dma_filter) {
728 			dev_err(mtd->dev.parent, "no DMA platform data\n");
729 			return -ENOENT;
730 		}
731 
732 		dma_cap_zero(mask);
733 		dma_cap_set(DMA_SLAVE, mask);
734 		host->dma_chan = dma_request_channel(mask, host->pdata->dma_filter, "nand-slc");
735 
736 		if (!host->dma_chan) {
737 			dev_err(mtd->dev.parent, "Failed to request DMA channel\n");
738 			return -EBUSY;
739 		}
740 	}
741 
742 	return 0;
743 }
744 
745 static struct lpc32xx_nand_cfg_slc *lpc32xx_parse_dt(struct device *dev)
746 {
747 	struct lpc32xx_nand_cfg_slc *ncfg;
748 	struct device_node *np = dev->of_node;
749 
750 	ncfg = devm_kzalloc(dev, sizeof(*ncfg), GFP_KERNEL);
751 	if (!ncfg)
752 		return NULL;
753 
754 	of_property_read_u32(np, "nxp,wdr-clks", &ncfg->wdr_clks);
755 	of_property_read_u32(np, "nxp,wwidth", &ncfg->wwidth);
756 	of_property_read_u32(np, "nxp,whold", &ncfg->whold);
757 	of_property_read_u32(np, "nxp,wsetup", &ncfg->wsetup);
758 	of_property_read_u32(np, "nxp,rdr-clks", &ncfg->rdr_clks);
759 	of_property_read_u32(np, "nxp,rwidth", &ncfg->rwidth);
760 	of_property_read_u32(np, "nxp,rhold", &ncfg->rhold);
761 	of_property_read_u32(np, "nxp,rsetup", &ncfg->rsetup);
762 
763 	if (!ncfg->wdr_clks || !ncfg->wwidth || !ncfg->whold ||
764 	    !ncfg->wsetup || !ncfg->rdr_clks || !ncfg->rwidth ||
765 	    !ncfg->rhold || !ncfg->rsetup) {
766 		dev_err(dev, "chip parameters not specified correctly\n");
767 		return NULL;
768 	}
769 
770 	return ncfg;
771 }
772 
773 static int lpc32xx_nand_attach_chip(struct nand_chip *chip)
774 {
775 	struct mtd_info *mtd = nand_to_mtd(chip);
776 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
777 
778 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
779 		return 0;
780 
781 	/* OOB and ECC CPU and DMA work areas */
782 	host->ecc_buf = (uint32_t *)(host->data_buf + LPC32XX_DMA_DATA_SIZE);
783 
784 	/*
785 	 * Small page FLASH has a unique OOB layout, but large and huge
786 	 * page FLASH use the standard layout. Small page FLASH uses a
787 	 * custom BBT marker layout.
788 	 */
789 	if (mtd->writesize <= 512)
790 		mtd_set_ooblayout(mtd, &lpc32xx_ooblayout_ops);
791 
792 	chip->ecc.placement = NAND_ECC_PLACEMENT_INTERLEAVED;
793 	/* These sizes remain the same regardless of page size */
794 	chip->ecc.size = 256;
795 	chip->ecc.strength = 1;
796 	chip->ecc.bytes = LPC32XX_SLC_DEV_ECC_BYTES;
797 	chip->ecc.prepad = 0;
798 	chip->ecc.postpad = 0;
799 	chip->ecc.read_page_raw = lpc32xx_nand_read_page_raw_syndrome;
800 	chip->ecc.read_page = lpc32xx_nand_read_page_syndrome;
801 	chip->ecc.write_page_raw = lpc32xx_nand_write_page_raw_syndrome;
802 	chip->ecc.write_page = lpc32xx_nand_write_page_syndrome;
803 	chip->ecc.write_oob = lpc32xx_nand_write_oob_syndrome;
804 	chip->ecc.read_oob = lpc32xx_nand_read_oob_syndrome;
805 	chip->ecc.calculate = lpc32xx_nand_ecc_calculate;
806 	chip->ecc.correct = rawnand_sw_hamming_correct;
807 	chip->ecc.hwctl = lpc32xx_nand_ecc_enable;
808 
809 	/*
810 	 * Use a custom BBT marker setup for small page FLASH that
811 	 * won't interfere with the ECC layout. Large and huge page
812 	 * FLASH use the standard layout.
813 	 */
814 	if ((chip->bbt_options & NAND_BBT_USE_FLASH) &&
815 	    mtd->writesize <= 512) {
816 		chip->bbt_td = &bbt_smallpage_main_descr;
817 		chip->bbt_md = &bbt_smallpage_mirror_descr;
818 	}
819 
820 	return 0;
821 }
822 
823 static const struct nand_controller_ops lpc32xx_nand_controller_ops = {
824 	.attach_chip = lpc32xx_nand_attach_chip,
825 };
826 
827 /*
828  * Probe for NAND controller
829  */
830 static int lpc32xx_nand_probe(struct platform_device *pdev)
831 {
832 	struct lpc32xx_nand_host *host;
833 	struct mtd_info *mtd;
834 	struct nand_chip *chip;
835 	struct resource *rc;
836 	int res;
837 
838 	/* Allocate memory for the device structure (and zero it) */
839 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
840 	if (!host)
841 		return -ENOMEM;
842 
843 	host->io_base = devm_platform_get_and_ioremap_resource(pdev, 0, &rc);
844 	if (IS_ERR(host->io_base))
845 		return PTR_ERR(host->io_base);
846 
847 	host->io_base_dma = rc->start;
848 	if (pdev->dev.of_node)
849 		host->ncfg = lpc32xx_parse_dt(&pdev->dev);
850 	if (!host->ncfg) {
851 		dev_err(&pdev->dev,
852 			"Missing or bad NAND config from device tree\n");
853 		return -ENOENT;
854 	}
855 
856 	/* Start with WP disabled, if available */
857 	host->wp_gpio = gpiod_get_optional(&pdev->dev, NULL, GPIOD_OUT_LOW);
858 	res = PTR_ERR_OR_ZERO(host->wp_gpio);
859 	if (res) {
860 		if (res != -EPROBE_DEFER)
861 			dev_err(&pdev->dev, "WP GPIO is not available: %d\n",
862 				res);
863 		return res;
864 	}
865 
866 	gpiod_set_consumer_name(host->wp_gpio, "NAND WP");
867 
868 	host->pdata = dev_get_platdata(&pdev->dev);
869 
870 	chip = &host->nand_chip;
871 	mtd = nand_to_mtd(chip);
872 	nand_set_controller_data(chip, host);
873 	nand_set_flash_node(chip, pdev->dev.of_node);
874 	mtd->owner = THIS_MODULE;
875 	mtd->dev.parent = &pdev->dev;
876 
877 	/* Get NAND clock */
878 	host->clk = devm_clk_get_enabled(&pdev->dev, NULL);
879 	if (IS_ERR(host->clk)) {
880 		dev_err(&pdev->dev, "Clock failure\n");
881 		res = -ENOENT;
882 		goto enable_wp;
883 	}
884 
885 	/* Set NAND IO addresses and command/ready functions */
886 	chip->legacy.IO_ADDR_R = SLC_DATA(host->io_base);
887 	chip->legacy.IO_ADDR_W = SLC_DATA(host->io_base);
888 	chip->legacy.cmd_ctrl = lpc32xx_nand_cmd_ctrl;
889 	chip->legacy.dev_ready = lpc32xx_nand_device_ready;
890 	chip->legacy.chip_delay = 20; /* 20us command delay time */
891 
892 	/* Init NAND controller */
893 	lpc32xx_nand_setup(host);
894 
895 	platform_set_drvdata(pdev, host);
896 
897 	/* NAND callbacks for LPC32xx SLC hardware */
898 	chip->legacy.read_byte = lpc32xx_nand_read_byte;
899 	chip->legacy.read_buf = lpc32xx_nand_read_buf;
900 	chip->legacy.write_buf = lpc32xx_nand_write_buf;
901 
902 	/*
903 	 * Allocate a large enough buffer for a single huge page plus
904 	 * extra space for the spare area and ECC storage area
905 	 */
906 	host->dma_buf_len = LPC32XX_DMA_DATA_SIZE + LPC32XX_ECC_SAVE_SIZE;
907 	host->data_buf = devm_kzalloc(&pdev->dev, host->dma_buf_len,
908 				      GFP_KERNEL);
909 	if (host->data_buf == NULL) {
910 		res = -ENOMEM;
911 		goto enable_wp;
912 	}
913 
914 	res = lpc32xx_nand_dma_setup(host);
915 	if (res) {
916 		res = -EIO;
917 		goto enable_wp;
918 	}
919 
920 	/* Find NAND device */
921 	chip->legacy.dummy_controller.ops = &lpc32xx_nand_controller_ops;
922 	res = nand_scan(chip, 1);
923 	if (res)
924 		goto release_dma;
925 
926 	mtd->name = "nxp_lpc3220_slc";
927 	res = mtd_device_register(mtd, host->ncfg->parts,
928 				  host->ncfg->num_parts);
929 	if (res)
930 		goto cleanup_nand;
931 
932 	return 0;
933 
934 cleanup_nand:
935 	nand_cleanup(chip);
936 release_dma:
937 	dma_release_channel(host->dma_chan);
938 enable_wp:
939 	lpc32xx_wp_enable(host);
940 
941 	return res;
942 }
943 
944 /*
945  * Remove NAND device.
946  */
947 static void lpc32xx_nand_remove(struct platform_device *pdev)
948 {
949 	uint32_t tmp;
950 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
951 	struct nand_chip *chip = &host->nand_chip;
952 	int ret;
953 
954 	ret = mtd_device_unregister(nand_to_mtd(chip));
955 	WARN_ON(ret);
956 	nand_cleanup(chip);
957 	dma_release_channel(host->dma_chan);
958 
959 	/* Force CE high */
960 	tmp = readl(SLC_CTRL(host->io_base));
961 	tmp &= ~SLCCFG_CE_LOW;
962 	writel(tmp, SLC_CTRL(host->io_base));
963 
964 	lpc32xx_wp_enable(host);
965 }
966 
967 static int lpc32xx_nand_resume(struct platform_device *pdev)
968 {
969 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
970 	int ret;
971 
972 	/* Re-enable NAND clock */
973 	ret = clk_prepare_enable(host->clk);
974 	if (ret)
975 		return ret;
976 
977 	/* Fresh init of NAND controller */
978 	lpc32xx_nand_setup(host);
979 
980 	/* Disable write protect */
981 	lpc32xx_wp_disable(host);
982 
983 	return 0;
984 }
985 
986 static int lpc32xx_nand_suspend(struct platform_device *pdev, pm_message_t pm)
987 {
988 	uint32_t tmp;
989 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
990 
991 	/* Force CE high */
992 	tmp = readl(SLC_CTRL(host->io_base));
993 	tmp &= ~SLCCFG_CE_LOW;
994 	writel(tmp, SLC_CTRL(host->io_base));
995 
996 	/* Enable write protect for safety */
997 	lpc32xx_wp_enable(host);
998 
999 	/* Disable clock */
1000 	clk_disable_unprepare(host->clk);
1001 
1002 	return 0;
1003 }
1004 
1005 static const struct of_device_id lpc32xx_nand_match[] = {
1006 	{ .compatible = "nxp,lpc3220-slc" },
1007 	{ /* sentinel */ },
1008 };
1009 MODULE_DEVICE_TABLE(of, lpc32xx_nand_match);
1010 
1011 static struct platform_driver lpc32xx_nand_driver = {
1012 	.probe		= lpc32xx_nand_probe,
1013 	.remove_new	= lpc32xx_nand_remove,
1014 	.resume		= pm_ptr(lpc32xx_nand_resume),
1015 	.suspend	= pm_ptr(lpc32xx_nand_suspend),
1016 	.driver		= {
1017 		.name	= LPC32XX_MODNAME,
1018 		.of_match_table = lpc32xx_nand_match,
1019 	},
1020 };
1021 
1022 module_platform_driver(lpc32xx_nand_driver);
1023 
1024 MODULE_LICENSE("GPL");
1025 MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
1026 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
1027 MODULE_DESCRIPTION("NAND driver for the NXP LPC32XX SLC controller");
1028