xref: /openbmc/linux/drivers/mtd/nand/raw/lpc32xx_slc.c (revision ed84ef1c)
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.h>
27 #include <linux/of.h>
28 #include <linux/of_gpio.h>
29 #include <linux/mtd/lpc32xx_slc.h>
30 #include <linux/mtd/nand-ecc-sw-hamming.h>
31 
32 #define LPC32XX_MODNAME		"lpc32xx-nand"
33 
34 /**********************************************************************
35 * SLC NAND controller register offsets
36 **********************************************************************/
37 
38 #define SLC_DATA(x)		(x + 0x000)
39 #define SLC_ADDR(x)		(x + 0x004)
40 #define SLC_CMD(x)		(x + 0x008)
41 #define SLC_STOP(x)		(x + 0x00C)
42 #define SLC_CTRL(x)		(x + 0x010)
43 #define SLC_CFG(x)		(x + 0x014)
44 #define SLC_STAT(x)		(x + 0x018)
45 #define SLC_INT_STAT(x)		(x + 0x01C)
46 #define SLC_IEN(x)		(x + 0x020)
47 #define SLC_ISR(x)		(x + 0x024)
48 #define SLC_ICR(x)		(x + 0x028)
49 #define SLC_TAC(x)		(x + 0x02C)
50 #define SLC_TC(x)		(x + 0x030)
51 #define SLC_ECC(x)		(x + 0x034)
52 #define SLC_DMA_DATA(x)		(x + 0x038)
53 
54 /**********************************************************************
55 * slc_ctrl register definitions
56 **********************************************************************/
57 #define SLCCTRL_SW_RESET	(1 << 2) /* Reset the NAND controller bit */
58 #define SLCCTRL_ECC_CLEAR	(1 << 1) /* Reset ECC bit */
59 #define SLCCTRL_DMA_START	(1 << 0) /* Start DMA channel bit */
60 
61 /**********************************************************************
62 * slc_cfg register definitions
63 **********************************************************************/
64 #define SLCCFG_CE_LOW		(1 << 5) /* Force CE low bit */
65 #define SLCCFG_DMA_ECC		(1 << 4) /* Enable DMA ECC bit */
66 #define SLCCFG_ECC_EN		(1 << 3) /* ECC enable bit */
67 #define SLCCFG_DMA_BURST	(1 << 2) /* DMA burst bit */
68 #define SLCCFG_DMA_DIR		(1 << 1) /* DMA write(0)/read(1) bit */
69 #define SLCCFG_WIDTH		(1 << 0) /* External device width, 0=8bit */
70 
71 /**********************************************************************
72 * slc_stat register definitions
73 **********************************************************************/
74 #define SLCSTAT_DMA_FIFO	(1 << 2) /* DMA FIFO has data bit */
75 #define SLCSTAT_SLC_FIFO	(1 << 1) /* SLC FIFO has data bit */
76 #define SLCSTAT_NAND_READY	(1 << 0) /* NAND device is ready bit */
77 
78 /**********************************************************************
79 * slc_int_stat, slc_ien, slc_isr, and slc_icr register definitions
80 **********************************************************************/
81 #define SLCSTAT_INT_TC		(1 << 1) /* Transfer count bit */
82 #define SLCSTAT_INT_RDY_EN	(1 << 0) /* Ready interrupt bit */
83 
84 /**********************************************************************
85 * slc_tac register definitions
86 **********************************************************************/
87 /* Computation of clock cycles on basis of controller and device clock rates */
88 #define SLCTAC_CLOCKS(c, n, s)	(min_t(u32, DIV_ROUND_UP(c, n) - 1, 0xF) << s)
89 
90 /* Clock setting for RDY write sample wait time in 2*n clocks */
91 #define SLCTAC_WDR(n)		(((n) & 0xF) << 28)
92 /* Write pulse width in clock cycles, 1 to 16 clocks */
93 #define SLCTAC_WWIDTH(c, n)	(SLCTAC_CLOCKS(c, n, 24))
94 /* Write hold time of control and data signals, 1 to 16 clocks */
95 #define SLCTAC_WHOLD(c, n)	(SLCTAC_CLOCKS(c, n, 20))
96 /* Write setup time of control and data signals, 1 to 16 clocks */
97 #define SLCTAC_WSETUP(c, n)	(SLCTAC_CLOCKS(c, n, 16))
98 /* Clock setting for RDY read sample wait time in 2*n clocks */
99 #define SLCTAC_RDR(n)		(((n) & 0xF) << 12)
100 /* Read pulse width in clock cycles, 1 to 16 clocks */
101 #define SLCTAC_RWIDTH(c, n)	(SLCTAC_CLOCKS(c, n, 8))
102 /* Read hold time of control and data signals, 1 to 16 clocks */
103 #define SLCTAC_RHOLD(c, n)	(SLCTAC_CLOCKS(c, n, 4))
104 /* Read setup time of control and data signals, 1 to 16 clocks */
105 #define SLCTAC_RSETUP(c, n)	(SLCTAC_CLOCKS(c, n, 0))
106 
107 /**********************************************************************
108 * slc_ecc register definitions
109 **********************************************************************/
110 /* ECC line party fetch macro */
111 #define SLCECC_TO_LINEPAR(n)	(((n) >> 6) & 0x7FFF)
112 #define SLCECC_TO_COLPAR(n)	((n) & 0x3F)
113 
114 /*
115  * DMA requires storage space for the DMA local buffer and the hardware ECC
116  * storage area. The DMA local buffer is only used if DMA mapping fails
117  * during runtime.
118  */
119 #define LPC32XX_DMA_DATA_SIZE		4096
120 #define LPC32XX_ECC_SAVE_SIZE		((4096 / 256) * 4)
121 
122 /* Number of bytes used for ECC stored in NAND per 256 bytes */
123 #define LPC32XX_SLC_DEV_ECC_BYTES	3
124 
125 /*
126  * If the NAND base clock frequency can't be fetched, this frequency will be
127  * used instead as the base. This rate is used to setup the timing registers
128  * used for NAND accesses.
129  */
130 #define LPC32XX_DEF_BUS_RATE		133250000
131 
132 /* Milliseconds for DMA FIFO timeout (unlikely anyway) */
133 #define LPC32XX_DMA_TIMEOUT		100
134 
135 /*
136  * NAND ECC Layout for small page NAND devices
137  * Note: For large and huge page devices, the default layouts are used
138  */
139 static int lpc32xx_ooblayout_ecc(struct mtd_info *mtd, int section,
140 				 struct mtd_oob_region *oobregion)
141 {
142 	if (section)
143 		return -ERANGE;
144 
145 	oobregion->length = 6;
146 	oobregion->offset = 10;
147 
148 	return 0;
149 }
150 
151 static int lpc32xx_ooblayout_free(struct mtd_info *mtd, int section,
152 				  struct mtd_oob_region *oobregion)
153 {
154 	if (section > 1)
155 		return -ERANGE;
156 
157 	if (!section) {
158 		oobregion->offset = 0;
159 		oobregion->length = 4;
160 	} else {
161 		oobregion->offset = 6;
162 		oobregion->length = 4;
163 	}
164 
165 	return 0;
166 }
167 
168 static const struct mtd_ooblayout_ops lpc32xx_ooblayout_ops = {
169 	.ecc = lpc32xx_ooblayout_ecc,
170 	.free = lpc32xx_ooblayout_free,
171 };
172 
173 static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
174 static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
175 
176 /*
177  * Small page FLASH BBT descriptors, marker at offset 0, version at offset 6
178  * Note: Large page devices used the default layout
179  */
180 static struct nand_bbt_descr bbt_smallpage_main_descr = {
181 	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
182 		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
183 	.offs =	0,
184 	.len = 4,
185 	.veroffs = 6,
186 	.maxblocks = 4,
187 	.pattern = bbt_pattern
188 };
189 
190 static struct nand_bbt_descr bbt_smallpage_mirror_descr = {
191 	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
192 		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
193 	.offs =	0,
194 	.len = 4,
195 	.veroffs = 6,
196 	.maxblocks = 4,
197 	.pattern = mirror_pattern
198 };
199 
200 /*
201  * NAND platform configuration structure
202  */
203 struct lpc32xx_nand_cfg_slc {
204 	uint32_t wdr_clks;
205 	uint32_t wwidth;
206 	uint32_t whold;
207 	uint32_t wsetup;
208 	uint32_t rdr_clks;
209 	uint32_t rwidth;
210 	uint32_t rhold;
211 	uint32_t rsetup;
212 	int wp_gpio;
213 	struct mtd_partition *parts;
214 	unsigned num_parts;
215 };
216 
217 struct lpc32xx_nand_host {
218 	struct nand_chip	nand_chip;
219 	struct lpc32xx_slc_platform_data *pdata;
220 	struct clk		*clk;
221 	void __iomem		*io_base;
222 	struct lpc32xx_nand_cfg_slc *ncfg;
223 
224 	struct completion	comp;
225 	struct dma_chan		*dma_chan;
226 	uint32_t		dma_buf_len;
227 	struct dma_slave_config	dma_slave_config;
228 	struct scatterlist	sgl;
229 
230 	/*
231 	 * DMA and CPU addresses of ECC work area and data buffer
232 	 */
233 	uint32_t		*ecc_buf;
234 	uint8_t			*data_buf;
235 	dma_addr_t		io_base_dma;
236 };
237 
238 static void lpc32xx_nand_setup(struct lpc32xx_nand_host *host)
239 {
240 	uint32_t clkrate, tmp;
241 
242 	/* Reset SLC controller */
243 	writel(SLCCTRL_SW_RESET, SLC_CTRL(host->io_base));
244 	udelay(1000);
245 
246 	/* Basic setup */
247 	writel(0, SLC_CFG(host->io_base));
248 	writel(0, SLC_IEN(host->io_base));
249 	writel((SLCSTAT_INT_TC | SLCSTAT_INT_RDY_EN),
250 		SLC_ICR(host->io_base));
251 
252 	/* Get base clock for SLC block */
253 	clkrate = clk_get_rate(host->clk);
254 	if (clkrate == 0)
255 		clkrate = LPC32XX_DEF_BUS_RATE;
256 
257 	/* Compute clock setup values */
258 	tmp = SLCTAC_WDR(host->ncfg->wdr_clks) |
259 		SLCTAC_WWIDTH(clkrate, host->ncfg->wwidth) |
260 		SLCTAC_WHOLD(clkrate, host->ncfg->whold) |
261 		SLCTAC_WSETUP(clkrate, host->ncfg->wsetup) |
262 		SLCTAC_RDR(host->ncfg->rdr_clks) |
263 		SLCTAC_RWIDTH(clkrate, host->ncfg->rwidth) |
264 		SLCTAC_RHOLD(clkrate, host->ncfg->rhold) |
265 		SLCTAC_RSETUP(clkrate, host->ncfg->rsetup);
266 	writel(tmp, SLC_TAC(host->io_base));
267 }
268 
269 /*
270  * Hardware specific access to control lines
271  */
272 static void lpc32xx_nand_cmd_ctrl(struct nand_chip *chip, int cmd,
273 				  unsigned int ctrl)
274 {
275 	uint32_t tmp;
276 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
277 
278 	/* Does CE state need to be changed? */
279 	tmp = readl(SLC_CFG(host->io_base));
280 	if (ctrl & NAND_NCE)
281 		tmp |= SLCCFG_CE_LOW;
282 	else
283 		tmp &= ~SLCCFG_CE_LOW;
284 	writel(tmp, SLC_CFG(host->io_base));
285 
286 	if (cmd != NAND_CMD_NONE) {
287 		if (ctrl & NAND_CLE)
288 			writel(cmd, SLC_CMD(host->io_base));
289 		else
290 			writel(cmd, SLC_ADDR(host->io_base));
291 	}
292 }
293 
294 /*
295  * Read the Device Ready pin
296  */
297 static int lpc32xx_nand_device_ready(struct nand_chip *chip)
298 {
299 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
300 	int rdy = 0;
301 
302 	if ((readl(SLC_STAT(host->io_base)) & SLCSTAT_NAND_READY) != 0)
303 		rdy = 1;
304 
305 	return rdy;
306 }
307 
308 /*
309  * Enable NAND write protect
310  */
311 static void lpc32xx_wp_enable(struct lpc32xx_nand_host *host)
312 {
313 	if (gpio_is_valid(host->ncfg->wp_gpio))
314 		gpio_set_value(host->ncfg->wp_gpio, 0);
315 }
316 
317 /*
318  * Disable NAND write protect
319  */
320 static void lpc32xx_wp_disable(struct lpc32xx_nand_host *host)
321 {
322 	if (gpio_is_valid(host->ncfg->wp_gpio))
323 		gpio_set_value(host->ncfg->wp_gpio, 1);
324 }
325 
326 /*
327  * Prepares SLC for transfers with H/W ECC enabled
328  */
329 static void lpc32xx_nand_ecc_enable(struct nand_chip *chip, int mode)
330 {
331 	/* Hardware ECC is enabled automatically in hardware as needed */
332 }
333 
334 /*
335  * Calculates the ECC for the data
336  */
337 static int lpc32xx_nand_ecc_calculate(struct nand_chip *chip,
338 				      const unsigned char *buf,
339 				      unsigned char *code)
340 {
341 	/*
342 	 * ECC is calculated automatically in hardware during syndrome read
343 	 * and write operations, so it doesn't need to be calculated here.
344 	 */
345 	return 0;
346 }
347 
348 /*
349  * Corrects the data
350  */
351 static int lpc32xx_nand_ecc_correct(struct nand_chip *chip,
352 				    unsigned char *buf,
353 				    unsigned char *read_ecc,
354 				    unsigned char *calc_ecc)
355 {
356 	return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
357 				      chip->ecc.size, false);
358 }
359 
360 /*
361  * Read a single byte from NAND device
362  */
363 static uint8_t lpc32xx_nand_read_byte(struct nand_chip *chip)
364 {
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 nand_chip *chip, u_char *buf, int len)
374 {
375 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
376 
377 	/* Direct device read with no ECC */
378 	while (len-- > 0)
379 		*buf++ = (uint8_t)readl(SLC_DATA(host->io_base));
380 }
381 
382 /*
383  * Simple device write without ECC
384  */
385 static void lpc32xx_nand_write_buf(struct nand_chip *chip, const uint8_t *buf,
386 				   int len)
387 {
388 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
389 
390 	/* Direct device write with no ECC */
391 	while (len-- > 0)
392 		writel((uint32_t)*buf++, SLC_DATA(host->io_base));
393 }
394 
395 /*
396  * Read the OOB data from the device without ECC using FIFO method
397  */
398 static int lpc32xx_nand_read_oob_syndrome(struct nand_chip *chip, int page)
399 {
400 	struct mtd_info *mtd = nand_to_mtd(chip);
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 nand_chip *chip, int page)
409 {
410 	struct mtd_info *mtd = nand_to_mtd(chip);
411 
412 	return nand_prog_page_op(chip, page, mtd->writesize, chip->oob_poi,
413 				 mtd->oobsize);
414 }
415 
416 /*
417  * Fills in the ECC fields in the OOB buffer with the hardware generated ECC
418  */
419 static void lpc32xx_slc_ecc_copy(uint8_t *spare, const uint32_t *ecc, int count)
420 {
421 	int i;
422 
423 	for (i = 0; i < (count * 3); i += 3) {
424 		uint32_t ce = ecc[i / 3];
425 		ce = ~(ce << 2) & 0xFFFFFF;
426 		spare[i + 2] = (uint8_t)(ce & 0xFF);
427 		ce >>= 8;
428 		spare[i + 1] = (uint8_t)(ce & 0xFF);
429 		ce >>= 8;
430 		spare[i] = (uint8_t)(ce & 0xFF);
431 	}
432 }
433 
434 static void lpc32xx_dma_complete_func(void *completion)
435 {
436 	complete(completion);
437 }
438 
439 static int lpc32xx_xmit_dma(struct mtd_info *mtd, dma_addr_t dma,
440 			    void *mem, int len, enum dma_transfer_direction dir)
441 {
442 	struct nand_chip *chip = mtd_to_nand(mtd);
443 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
444 	struct dma_async_tx_descriptor *desc;
445 	int flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
446 	int res;
447 
448 	host->dma_slave_config.direction = dir;
449 	host->dma_slave_config.src_addr = dma;
450 	host->dma_slave_config.dst_addr = dma;
451 	host->dma_slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
452 	host->dma_slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
453 	host->dma_slave_config.src_maxburst = 4;
454 	host->dma_slave_config.dst_maxburst = 4;
455 	/* DMA controller does flow control: */
456 	host->dma_slave_config.device_fc = false;
457 	if (dmaengine_slave_config(host->dma_chan, &host->dma_slave_config)) {
458 		dev_err(mtd->dev.parent, "Failed to setup DMA slave\n");
459 		return -ENXIO;
460 	}
461 
462 	sg_init_one(&host->sgl, mem, len);
463 
464 	res = dma_map_sg(host->dma_chan->device->dev, &host->sgl, 1,
465 			 DMA_BIDIRECTIONAL);
466 	if (res != 1) {
467 		dev_err(mtd->dev.parent, "Failed to map sg list\n");
468 		return -ENXIO;
469 	}
470 	desc = dmaengine_prep_slave_sg(host->dma_chan, &host->sgl, 1, dir,
471 				       flags);
472 	if (!desc) {
473 		dev_err(mtd->dev.parent, "Failed to prepare slave sg\n");
474 		goto out1;
475 	}
476 
477 	init_completion(&host->comp);
478 	desc->callback = lpc32xx_dma_complete_func;
479 	desc->callback_param = &host->comp;
480 
481 	dmaengine_submit(desc);
482 	dma_async_issue_pending(host->dma_chan);
483 
484 	wait_for_completion_timeout(&host->comp, msecs_to_jiffies(1000));
485 
486 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
487 		     DMA_BIDIRECTIONAL);
488 
489 	return 0;
490 out1:
491 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
492 		     DMA_BIDIRECTIONAL);
493 	return -ENXIO;
494 }
495 
496 /*
497  * DMA read/write transfers with ECC support
498  */
499 static int lpc32xx_xfer(struct mtd_info *mtd, uint8_t *buf, int eccsubpages,
500 			int read)
501 {
502 	struct nand_chip *chip = mtd_to_nand(mtd);
503 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
504 	int i, status = 0;
505 	unsigned long timeout;
506 	int res;
507 	enum dma_transfer_direction dir =
508 		read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
509 	uint8_t *dma_buf;
510 	bool dma_mapped;
511 
512 	if ((void *)buf <= high_memory) {
513 		dma_buf = buf;
514 		dma_mapped = true;
515 	} else {
516 		dma_buf = host->data_buf;
517 		dma_mapped = false;
518 		if (!read)
519 			memcpy(host->data_buf, buf, mtd->writesize);
520 	}
521 
522 	if (read) {
523 		writel(readl(SLC_CFG(host->io_base)) |
524 		       SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
525 		       SLCCFG_DMA_BURST, SLC_CFG(host->io_base));
526 	} else {
527 		writel((readl(SLC_CFG(host->io_base)) |
528 			SLCCFG_ECC_EN | SLCCFG_DMA_ECC | SLCCFG_DMA_BURST) &
529 		       ~SLCCFG_DMA_DIR,
530 			SLC_CFG(host->io_base));
531 	}
532 
533 	/* Clear initial ECC */
534 	writel(SLCCTRL_ECC_CLEAR, SLC_CTRL(host->io_base));
535 
536 	/* Transfer size is data area only */
537 	writel(mtd->writesize, SLC_TC(host->io_base));
538 
539 	/* Start transfer in the NAND controller */
540 	writel(readl(SLC_CTRL(host->io_base)) | SLCCTRL_DMA_START,
541 	       SLC_CTRL(host->io_base));
542 
543 	for (i = 0; i < chip->ecc.steps; i++) {
544 		/* Data */
545 		res = lpc32xx_xmit_dma(mtd, SLC_DMA_DATA(host->io_base_dma),
546 				       dma_buf + i * chip->ecc.size,
547 				       mtd->writesize / chip->ecc.steps, dir);
548 		if (res)
549 			return res;
550 
551 		/* Always _read_ ECC */
552 		if (i == chip->ecc.steps - 1)
553 			break;
554 		if (!read) /* ECC availability delayed on write */
555 			udelay(10);
556 		res = lpc32xx_xmit_dma(mtd, SLC_ECC(host->io_base_dma),
557 				       &host->ecc_buf[i], 4, DMA_DEV_TO_MEM);
558 		if (res)
559 			return res;
560 	}
561 
562 	/*
563 	 * According to NXP, the DMA can be finished here, but the NAND
564 	 * controller may still have buffered data. After porting to using the
565 	 * dmaengine DMA driver (amba-pl080), the condition (DMA_FIFO empty)
566 	 * appears to be always true, according to tests. Keeping the check for
567 	 * safety reasons for now.
568 	 */
569 	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) {
570 		dev_warn(mtd->dev.parent, "FIFO not empty!\n");
571 		timeout = jiffies + msecs_to_jiffies(LPC32XX_DMA_TIMEOUT);
572 		while ((readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) &&
573 		       time_before(jiffies, timeout))
574 			cpu_relax();
575 		if (!time_before(jiffies, timeout)) {
576 			dev_err(mtd->dev.parent, "FIFO held data too long\n");
577 			status = -EIO;
578 		}
579 	}
580 
581 	/* Read last calculated ECC value */
582 	if (!read)
583 		udelay(10);
584 	host->ecc_buf[chip->ecc.steps - 1] =
585 		readl(SLC_ECC(host->io_base));
586 
587 	/* Flush DMA */
588 	dmaengine_terminate_all(host->dma_chan);
589 
590 	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO ||
591 	    readl(SLC_TC(host->io_base))) {
592 		/* Something is left in the FIFO, something is wrong */
593 		dev_err(mtd->dev.parent, "DMA FIFO failure\n");
594 		status = -EIO;
595 	}
596 
597 	/* Stop DMA & HW ECC */
598 	writel(readl(SLC_CTRL(host->io_base)) & ~SLCCTRL_DMA_START,
599 	       SLC_CTRL(host->io_base));
600 	writel(readl(SLC_CFG(host->io_base)) &
601 	       ~(SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
602 		 SLCCFG_DMA_BURST), SLC_CFG(host->io_base));
603 
604 	if (!dma_mapped && read)
605 		memcpy(buf, host->data_buf, mtd->writesize);
606 
607 	return status;
608 }
609 
610 /*
611  * Read the data and OOB data from the device, use ECC correction with the
612  * data, disable ECC for the OOB data
613  */
614 static int lpc32xx_nand_read_page_syndrome(struct nand_chip *chip, uint8_t *buf,
615 					   int oob_required, int page)
616 {
617 	struct mtd_info *mtd = nand_to_mtd(chip);
618 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
619 	struct mtd_oob_region oobregion = { };
620 	int stat, i, status, error;
621 	uint8_t *oobecc, tmpecc[LPC32XX_ECC_SAVE_SIZE];
622 
623 	/* Issue read command */
624 	nand_read_page_op(chip, page, 0, NULL, 0);
625 
626 	/* Read data and oob, calculate ECC */
627 	status = lpc32xx_xfer(mtd, buf, chip->ecc.steps, 1);
628 
629 	/* Get OOB data */
630 	chip->legacy.read_buf(chip, chip->oob_poi, mtd->oobsize);
631 
632 	/* Convert to stored ECC format */
633 	lpc32xx_slc_ecc_copy(tmpecc, (uint32_t *) host->ecc_buf, chip->ecc.steps);
634 
635 	/* Pointer to ECC data retrieved from NAND spare area */
636 	error = mtd_ooblayout_ecc(mtd, 0, &oobregion);
637 	if (error)
638 		return error;
639 
640 	oobecc = chip->oob_poi + oobregion.offset;
641 
642 	for (i = 0; i < chip->ecc.steps; i++) {
643 		stat = chip->ecc.correct(chip, buf, oobecc,
644 					 &tmpecc[i * chip->ecc.bytes]);
645 		if (stat < 0)
646 			mtd->ecc_stats.failed++;
647 		else
648 			mtd->ecc_stats.corrected += stat;
649 
650 		buf += chip->ecc.size;
651 		oobecc += chip->ecc.bytes;
652 	}
653 
654 	return status;
655 }
656 
657 /*
658  * Read the data and OOB data from the device, no ECC correction with the
659  * data or OOB data
660  */
661 static int lpc32xx_nand_read_page_raw_syndrome(struct nand_chip *chip,
662 					       uint8_t *buf, int oob_required,
663 					       int page)
664 {
665 	struct mtd_info *mtd = nand_to_mtd(chip);
666 
667 	/* Issue read command */
668 	nand_read_page_op(chip, page, 0, NULL, 0);
669 
670 	/* Raw reads can just use the FIFO interface */
671 	chip->legacy.read_buf(chip, buf, chip->ecc.size * chip->ecc.steps);
672 	chip->legacy.read_buf(chip, chip->oob_poi, mtd->oobsize);
673 
674 	return 0;
675 }
676 
677 /*
678  * Write the data and OOB data to the device, use ECC with the data,
679  * disable ECC for the OOB data
680  */
681 static int lpc32xx_nand_write_page_syndrome(struct nand_chip *chip,
682 					    const uint8_t *buf,
683 					    int oob_required, int page)
684 {
685 	struct mtd_info *mtd = nand_to_mtd(chip);
686 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
687 	struct mtd_oob_region oobregion = { };
688 	uint8_t *pb;
689 	int error;
690 
691 	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
692 
693 	/* Write data, calculate ECC on outbound data */
694 	error = lpc32xx_xfer(mtd, (uint8_t *)buf, chip->ecc.steps, 0);
695 	if (error)
696 		return error;
697 
698 	/*
699 	 * The calculated ECC needs some manual work done to it before
700 	 * committing it to NAND. Process the calculated ECC and place
701 	 * the resultant values directly into the OOB buffer. */
702 	error = mtd_ooblayout_ecc(mtd, 0, &oobregion);
703 	if (error)
704 		return error;
705 
706 	pb = chip->oob_poi + oobregion.offset;
707 	lpc32xx_slc_ecc_copy(pb, (uint32_t *)host->ecc_buf, chip->ecc.steps);
708 
709 	/* Write ECC data to device */
710 	chip->legacy.write_buf(chip, chip->oob_poi, mtd->oobsize);
711 
712 	return nand_prog_page_end_op(chip);
713 }
714 
715 /*
716  * Write the data and OOB data to the device, no ECC correction with the
717  * data or OOB data
718  */
719 static int lpc32xx_nand_write_page_raw_syndrome(struct nand_chip *chip,
720 						const uint8_t *buf,
721 						int oob_required, int page)
722 {
723 	struct mtd_info *mtd = nand_to_mtd(chip);
724 
725 	/* Raw writes can just use the FIFO interface */
726 	nand_prog_page_begin_op(chip, page, 0, buf,
727 				chip->ecc.size * chip->ecc.steps);
728 	chip->legacy.write_buf(chip, chip->oob_poi, mtd->oobsize);
729 
730 	return nand_prog_page_end_op(chip);
731 }
732 
733 static int lpc32xx_nand_dma_setup(struct lpc32xx_nand_host *host)
734 {
735 	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
736 	dma_cap_mask_t mask;
737 
738 	if (!host->pdata || !host->pdata->dma_filter) {
739 		dev_err(mtd->dev.parent, "no DMA platform data\n");
740 		return -ENOENT;
741 	}
742 
743 	dma_cap_zero(mask);
744 	dma_cap_set(DMA_SLAVE, mask);
745 	host->dma_chan = dma_request_channel(mask, host->pdata->dma_filter,
746 					     "nand-slc");
747 	if (!host->dma_chan) {
748 		dev_err(mtd->dev.parent, "Failed to request DMA channel\n");
749 		return -EBUSY;
750 	}
751 
752 	return 0;
753 }
754 
755 static struct lpc32xx_nand_cfg_slc *lpc32xx_parse_dt(struct device *dev)
756 {
757 	struct lpc32xx_nand_cfg_slc *ncfg;
758 	struct device_node *np = dev->of_node;
759 
760 	ncfg = devm_kzalloc(dev, sizeof(*ncfg), GFP_KERNEL);
761 	if (!ncfg)
762 		return NULL;
763 
764 	of_property_read_u32(np, "nxp,wdr-clks", &ncfg->wdr_clks);
765 	of_property_read_u32(np, "nxp,wwidth", &ncfg->wwidth);
766 	of_property_read_u32(np, "nxp,whold", &ncfg->whold);
767 	of_property_read_u32(np, "nxp,wsetup", &ncfg->wsetup);
768 	of_property_read_u32(np, "nxp,rdr-clks", &ncfg->rdr_clks);
769 	of_property_read_u32(np, "nxp,rwidth", &ncfg->rwidth);
770 	of_property_read_u32(np, "nxp,rhold", &ncfg->rhold);
771 	of_property_read_u32(np, "nxp,rsetup", &ncfg->rsetup);
772 
773 	if (!ncfg->wdr_clks || !ncfg->wwidth || !ncfg->whold ||
774 	    !ncfg->wsetup || !ncfg->rdr_clks || !ncfg->rwidth ||
775 	    !ncfg->rhold || !ncfg->rsetup) {
776 		dev_err(dev, "chip parameters not specified correctly\n");
777 		return NULL;
778 	}
779 
780 	ncfg->wp_gpio = of_get_named_gpio(np, "gpios", 0);
781 
782 	return ncfg;
783 }
784 
785 static int lpc32xx_nand_attach_chip(struct nand_chip *chip)
786 {
787 	struct mtd_info *mtd = nand_to_mtd(chip);
788 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
789 
790 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
791 		return 0;
792 
793 	/* OOB and ECC CPU and DMA work areas */
794 	host->ecc_buf = (uint32_t *)(host->data_buf + LPC32XX_DMA_DATA_SIZE);
795 
796 	/*
797 	 * Small page FLASH has a unique OOB layout, but large and huge
798 	 * page FLASH use the standard layout. Small page FLASH uses a
799 	 * custom BBT marker layout.
800 	 */
801 	if (mtd->writesize <= 512)
802 		mtd_set_ooblayout(mtd, &lpc32xx_ooblayout_ops);
803 
804 	chip->ecc.placement = NAND_ECC_PLACEMENT_INTERLEAVED;
805 	/* These sizes remain the same regardless of page size */
806 	chip->ecc.size = 256;
807 	chip->ecc.strength = 1;
808 	chip->ecc.bytes = LPC32XX_SLC_DEV_ECC_BYTES;
809 	chip->ecc.prepad = 0;
810 	chip->ecc.postpad = 0;
811 	chip->ecc.read_page_raw = lpc32xx_nand_read_page_raw_syndrome;
812 	chip->ecc.read_page = lpc32xx_nand_read_page_syndrome;
813 	chip->ecc.write_page_raw = lpc32xx_nand_write_page_raw_syndrome;
814 	chip->ecc.write_page = lpc32xx_nand_write_page_syndrome;
815 	chip->ecc.write_oob = lpc32xx_nand_write_oob_syndrome;
816 	chip->ecc.read_oob = lpc32xx_nand_read_oob_syndrome;
817 	chip->ecc.calculate = lpc32xx_nand_ecc_calculate;
818 	chip->ecc.correct = lpc32xx_nand_ecc_correct;
819 	chip->ecc.hwctl = lpc32xx_nand_ecc_enable;
820 
821 	/*
822 	 * Use a custom BBT marker setup for small page FLASH that
823 	 * won't interfere with the ECC layout. Large and huge page
824 	 * FLASH use the standard layout.
825 	 */
826 	if ((chip->bbt_options & NAND_BBT_USE_FLASH) &&
827 	    mtd->writesize <= 512) {
828 		chip->bbt_td = &bbt_smallpage_main_descr;
829 		chip->bbt_md = &bbt_smallpage_mirror_descr;
830 	}
831 
832 	return 0;
833 }
834 
835 static const struct nand_controller_ops lpc32xx_nand_controller_ops = {
836 	.attach_chip = lpc32xx_nand_attach_chip,
837 };
838 
839 /*
840  * Probe for NAND controller
841  */
842 static int lpc32xx_nand_probe(struct platform_device *pdev)
843 {
844 	struct lpc32xx_nand_host *host;
845 	struct mtd_info *mtd;
846 	struct nand_chip *chip;
847 	struct resource *rc;
848 	int res;
849 
850 	/* Allocate memory for the device structure (and zero it) */
851 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
852 	if (!host)
853 		return -ENOMEM;
854 
855 	rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
856 	host->io_base = devm_ioremap_resource(&pdev->dev, rc);
857 	if (IS_ERR(host->io_base))
858 		return PTR_ERR(host->io_base);
859 
860 	host->io_base_dma = rc->start;
861 	if (pdev->dev.of_node)
862 		host->ncfg = lpc32xx_parse_dt(&pdev->dev);
863 	if (!host->ncfg) {
864 		dev_err(&pdev->dev,
865 			"Missing or bad NAND config from device tree\n");
866 		return -ENOENT;
867 	}
868 	if (host->ncfg->wp_gpio == -EPROBE_DEFER)
869 		return -EPROBE_DEFER;
870 	if (gpio_is_valid(host->ncfg->wp_gpio) && devm_gpio_request(&pdev->dev,
871 			host->ncfg->wp_gpio, "NAND WP")) {
872 		dev_err(&pdev->dev, "GPIO not available\n");
873 		return -EBUSY;
874 	}
875 	lpc32xx_wp_disable(host);
876 
877 	host->pdata = dev_get_platdata(&pdev->dev);
878 
879 	chip = &host->nand_chip;
880 	mtd = nand_to_mtd(chip);
881 	nand_set_controller_data(chip, host);
882 	nand_set_flash_node(chip, pdev->dev.of_node);
883 	mtd->owner = THIS_MODULE;
884 	mtd->dev.parent = &pdev->dev;
885 
886 	/* Get NAND clock */
887 	host->clk = devm_clk_get(&pdev->dev, NULL);
888 	if (IS_ERR(host->clk)) {
889 		dev_err(&pdev->dev, "Clock failure\n");
890 		res = -ENOENT;
891 		goto enable_wp;
892 	}
893 	res = clk_prepare_enable(host->clk);
894 	if (res)
895 		goto enable_wp;
896 
897 	/* Set NAND IO addresses and command/ready functions */
898 	chip->legacy.IO_ADDR_R = SLC_DATA(host->io_base);
899 	chip->legacy.IO_ADDR_W = SLC_DATA(host->io_base);
900 	chip->legacy.cmd_ctrl = lpc32xx_nand_cmd_ctrl;
901 	chip->legacy.dev_ready = lpc32xx_nand_device_ready;
902 	chip->legacy.chip_delay = 20; /* 20us command delay time */
903 
904 	/* Init NAND controller */
905 	lpc32xx_nand_setup(host);
906 
907 	platform_set_drvdata(pdev, host);
908 
909 	/* NAND callbacks for LPC32xx SLC hardware */
910 	chip->legacy.read_byte = lpc32xx_nand_read_byte;
911 	chip->legacy.read_buf = lpc32xx_nand_read_buf;
912 	chip->legacy.write_buf = lpc32xx_nand_write_buf;
913 
914 	/*
915 	 * Allocate a large enough buffer for a single huge page plus
916 	 * extra space for the spare area and ECC storage area
917 	 */
918 	host->dma_buf_len = LPC32XX_DMA_DATA_SIZE + LPC32XX_ECC_SAVE_SIZE;
919 	host->data_buf = devm_kzalloc(&pdev->dev, host->dma_buf_len,
920 				      GFP_KERNEL);
921 	if (host->data_buf == NULL) {
922 		res = -ENOMEM;
923 		goto unprepare_clk;
924 	}
925 
926 	res = lpc32xx_nand_dma_setup(host);
927 	if (res) {
928 		res = -EIO;
929 		goto unprepare_clk;
930 	}
931 
932 	/* Find NAND device */
933 	chip->legacy.dummy_controller.ops = &lpc32xx_nand_controller_ops;
934 	res = nand_scan(chip, 1);
935 	if (res)
936 		goto release_dma;
937 
938 	mtd->name = "nxp_lpc3220_slc";
939 	res = mtd_device_register(mtd, host->ncfg->parts,
940 				  host->ncfg->num_parts);
941 	if (res)
942 		goto cleanup_nand;
943 
944 	return 0;
945 
946 cleanup_nand:
947 	nand_cleanup(chip);
948 release_dma:
949 	dma_release_channel(host->dma_chan);
950 unprepare_clk:
951 	clk_disable_unprepare(host->clk);
952 enable_wp:
953 	lpc32xx_wp_enable(host);
954 
955 	return res;
956 }
957 
958 /*
959  * Remove NAND device.
960  */
961 static int lpc32xx_nand_remove(struct platform_device *pdev)
962 {
963 	uint32_t tmp;
964 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
965 	struct nand_chip *chip = &host->nand_chip;
966 	int ret;
967 
968 	ret = mtd_device_unregister(nand_to_mtd(chip));
969 	WARN_ON(ret);
970 	nand_cleanup(chip);
971 	dma_release_channel(host->dma_chan);
972 
973 	/* Force CE high */
974 	tmp = readl(SLC_CTRL(host->io_base));
975 	tmp &= ~SLCCFG_CE_LOW;
976 	writel(tmp, SLC_CTRL(host->io_base));
977 
978 	clk_disable_unprepare(host->clk);
979 	lpc32xx_wp_enable(host);
980 
981 	return 0;
982 }
983 
984 #ifdef CONFIG_PM
985 static int lpc32xx_nand_resume(struct platform_device *pdev)
986 {
987 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
988 	int ret;
989 
990 	/* Re-enable NAND clock */
991 	ret = clk_prepare_enable(host->clk);
992 	if (ret)
993 		return ret;
994 
995 	/* Fresh init of NAND controller */
996 	lpc32xx_nand_setup(host);
997 
998 	/* Disable write protect */
999 	lpc32xx_wp_disable(host);
1000 
1001 	return 0;
1002 }
1003 
1004 static int lpc32xx_nand_suspend(struct platform_device *pdev, pm_message_t pm)
1005 {
1006 	uint32_t tmp;
1007 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
1008 
1009 	/* Force CE high */
1010 	tmp = readl(SLC_CTRL(host->io_base));
1011 	tmp &= ~SLCCFG_CE_LOW;
1012 	writel(tmp, SLC_CTRL(host->io_base));
1013 
1014 	/* Enable write protect for safety */
1015 	lpc32xx_wp_enable(host);
1016 
1017 	/* Disable clock */
1018 	clk_disable_unprepare(host->clk);
1019 
1020 	return 0;
1021 }
1022 
1023 #else
1024 #define lpc32xx_nand_resume NULL
1025 #define lpc32xx_nand_suspend NULL
1026 #endif
1027 
1028 static const struct of_device_id lpc32xx_nand_match[] = {
1029 	{ .compatible = "nxp,lpc3220-slc" },
1030 	{ /* sentinel */ },
1031 };
1032 MODULE_DEVICE_TABLE(of, lpc32xx_nand_match);
1033 
1034 static struct platform_driver lpc32xx_nand_driver = {
1035 	.probe		= lpc32xx_nand_probe,
1036 	.remove		= lpc32xx_nand_remove,
1037 	.resume		= lpc32xx_nand_resume,
1038 	.suspend	= lpc32xx_nand_suspend,
1039 	.driver		= {
1040 		.name	= LPC32XX_MODNAME,
1041 		.of_match_table = lpc32xx_nand_match,
1042 	},
1043 };
1044 
1045 module_platform_driver(lpc32xx_nand_driver);
1046 
1047 MODULE_LICENSE("GPL");
1048 MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
1049 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
1050 MODULE_DESCRIPTION("NAND driver for the NXP LPC32XX SLC controller");
1051