xref: /openbmc/linux/drivers/mtd/nand/raw/lpc32xx_slc.c (revision 842ed298)
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 
31 #define LPC32XX_MODNAME		"lpc32xx-nand"
32 
33 /**********************************************************************
34 * SLC NAND controller register offsets
35 **********************************************************************/
36 
37 #define SLC_DATA(x)		(x + 0x000)
38 #define SLC_ADDR(x)		(x + 0x004)
39 #define SLC_CMD(x)		(x + 0x008)
40 #define SLC_STOP(x)		(x + 0x00C)
41 #define SLC_CTRL(x)		(x + 0x010)
42 #define SLC_CFG(x)		(x + 0x014)
43 #define SLC_STAT(x)		(x + 0x018)
44 #define SLC_INT_STAT(x)		(x + 0x01C)
45 #define SLC_IEN(x)		(x + 0x020)
46 #define SLC_ISR(x)		(x + 0x024)
47 #define SLC_ICR(x)		(x + 0x028)
48 #define SLC_TAC(x)		(x + 0x02C)
49 #define SLC_TC(x)		(x + 0x030)
50 #define SLC_ECC(x)		(x + 0x034)
51 #define SLC_DMA_DATA(x)		(x + 0x038)
52 
53 /**********************************************************************
54 * slc_ctrl register definitions
55 **********************************************************************/
56 #define SLCCTRL_SW_RESET	(1 << 2) /* Reset the NAND controller bit */
57 #define SLCCTRL_ECC_CLEAR	(1 << 1) /* Reset ECC bit */
58 #define SLCCTRL_DMA_START	(1 << 0) /* Start DMA channel bit */
59 
60 /**********************************************************************
61 * slc_cfg register definitions
62 **********************************************************************/
63 #define SLCCFG_CE_LOW		(1 << 5) /* Force CE low bit */
64 #define SLCCFG_DMA_ECC		(1 << 4) /* Enable DMA ECC bit */
65 #define SLCCFG_ECC_EN		(1 << 3) /* ECC enable bit */
66 #define SLCCFG_DMA_BURST	(1 << 2) /* DMA burst bit */
67 #define SLCCFG_DMA_DIR		(1 << 1) /* DMA write(0)/read(1) bit */
68 #define SLCCFG_WIDTH		(1 << 0) /* External device width, 0=8bit */
69 
70 /**********************************************************************
71 * slc_stat register definitions
72 **********************************************************************/
73 #define SLCSTAT_DMA_FIFO	(1 << 2) /* DMA FIFO has data bit */
74 #define SLCSTAT_SLC_FIFO	(1 << 1) /* SLC FIFO has data bit */
75 #define SLCSTAT_NAND_READY	(1 << 0) /* NAND device is ready bit */
76 
77 /**********************************************************************
78 * slc_int_stat, slc_ien, slc_isr, and slc_icr register definitions
79 **********************************************************************/
80 #define SLCSTAT_INT_TC		(1 << 1) /* Transfer count bit */
81 #define SLCSTAT_INT_RDY_EN	(1 << 0) /* Ready interrupt bit */
82 
83 /**********************************************************************
84 * slc_tac register definitions
85 **********************************************************************/
86 /* Computation of clock cycles on basis of controller and device clock rates */
87 #define SLCTAC_CLOCKS(c, n, s)	(min_t(u32, DIV_ROUND_UP(c, n) - 1, 0xF) << s)
88 
89 /* Clock setting for RDY write sample wait time in 2*n clocks */
90 #define SLCTAC_WDR(n)		(((n) & 0xF) << 28)
91 /* Write pulse width in clock cycles, 1 to 16 clocks */
92 #define SLCTAC_WWIDTH(c, n)	(SLCTAC_CLOCKS(c, n, 24))
93 /* Write hold time of control and data signals, 1 to 16 clocks */
94 #define SLCTAC_WHOLD(c, n)	(SLCTAC_CLOCKS(c, n, 20))
95 /* Write setup time of control and data signals, 1 to 16 clocks */
96 #define SLCTAC_WSETUP(c, n)	(SLCTAC_CLOCKS(c, n, 16))
97 /* Clock setting for RDY read sample wait time in 2*n clocks */
98 #define SLCTAC_RDR(n)		(((n) & 0xF) << 12)
99 /* Read pulse width in clock cycles, 1 to 16 clocks */
100 #define SLCTAC_RWIDTH(c, n)	(SLCTAC_CLOCKS(c, n, 8))
101 /* Read hold time of control and data signals, 1 to 16 clocks */
102 #define SLCTAC_RHOLD(c, n)	(SLCTAC_CLOCKS(c, n, 4))
103 /* Read setup time of control and data signals, 1 to 16 clocks */
104 #define SLCTAC_RSETUP(c, n)	(SLCTAC_CLOCKS(c, n, 0))
105 
106 /**********************************************************************
107 * slc_ecc register definitions
108 **********************************************************************/
109 /* ECC line party fetch macro */
110 #define SLCECC_TO_LINEPAR(n)	(((n) >> 6) & 0x7FFF)
111 #define SLCECC_TO_COLPAR(n)	((n) & 0x3F)
112 
113 /*
114  * DMA requires storage space for the DMA local buffer and the hardware ECC
115  * storage area. The DMA local buffer is only used if DMA mapping fails
116  * during runtime.
117  */
118 #define LPC32XX_DMA_DATA_SIZE		4096
119 #define LPC32XX_ECC_SAVE_SIZE		((4096 / 256) * 4)
120 
121 /* Number of bytes used for ECC stored in NAND per 256 bytes */
122 #define LPC32XX_SLC_DEV_ECC_BYTES	3
123 
124 /*
125  * If the NAND base clock frequency can't be fetched, this frequency will be
126  * used instead as the base. This rate is used to setup the timing registers
127  * used for NAND accesses.
128  */
129 #define LPC32XX_DEF_BUS_RATE		133250000
130 
131 /* Milliseconds for DMA FIFO timeout (unlikely anyway) */
132 #define LPC32XX_DMA_TIMEOUT		100
133 
134 /*
135  * NAND ECC Layout for small page NAND devices
136  * Note: For large and huge page devices, the default layouts are used
137  */
138 static int lpc32xx_ooblayout_ecc(struct mtd_info *mtd, int section,
139 				 struct mtd_oob_region *oobregion)
140 {
141 	if (section)
142 		return -ERANGE;
143 
144 	oobregion->length = 6;
145 	oobregion->offset = 10;
146 
147 	return 0;
148 }
149 
150 static int lpc32xx_ooblayout_free(struct mtd_info *mtd, int section,
151 				  struct mtd_oob_region *oobregion)
152 {
153 	if (section > 1)
154 		return -ERANGE;
155 
156 	if (!section) {
157 		oobregion->offset = 0;
158 		oobregion->length = 4;
159 	} else {
160 		oobregion->offset = 6;
161 		oobregion->length = 4;
162 	}
163 
164 	return 0;
165 }
166 
167 static const struct mtd_ooblayout_ops lpc32xx_ooblayout_ops = {
168 	.ecc = lpc32xx_ooblayout_ecc,
169 	.free = lpc32xx_ooblayout_free,
170 };
171 
172 static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
173 static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
174 
175 /*
176  * Small page FLASH BBT descriptors, marker at offset 0, version at offset 6
177  * Note: Large page devices used the default layout
178  */
179 static struct nand_bbt_descr bbt_smallpage_main_descr = {
180 	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
181 		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
182 	.offs =	0,
183 	.len = 4,
184 	.veroffs = 6,
185 	.maxblocks = 4,
186 	.pattern = bbt_pattern
187 };
188 
189 static struct nand_bbt_descr bbt_smallpage_mirror_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 = mirror_pattern
197 };
198 
199 /*
200  * NAND platform configuration structure
201  */
202 struct lpc32xx_nand_cfg_slc {
203 	uint32_t wdr_clks;
204 	uint32_t wwidth;
205 	uint32_t whold;
206 	uint32_t wsetup;
207 	uint32_t rdr_clks;
208 	uint32_t rwidth;
209 	uint32_t rhold;
210 	uint32_t rsetup;
211 	int wp_gpio;
212 	struct mtd_partition *parts;
213 	unsigned num_parts;
214 };
215 
216 struct lpc32xx_nand_host {
217 	struct nand_chip	nand_chip;
218 	struct lpc32xx_slc_platform_data *pdata;
219 	struct clk		*clk;
220 	void __iomem		*io_base;
221 	struct lpc32xx_nand_cfg_slc *ncfg;
222 
223 	struct completion	comp;
224 	struct dma_chan		*dma_chan;
225 	uint32_t		dma_buf_len;
226 	struct dma_slave_config	dma_slave_config;
227 	struct scatterlist	sgl;
228 
229 	/*
230 	 * DMA and CPU addresses of ECC work area and data buffer
231 	 */
232 	uint32_t		*ecc_buf;
233 	uint8_t			*data_buf;
234 	dma_addr_t		io_base_dma;
235 };
236 
237 static void lpc32xx_nand_setup(struct lpc32xx_nand_host *host)
238 {
239 	uint32_t clkrate, tmp;
240 
241 	/* Reset SLC controller */
242 	writel(SLCCTRL_SW_RESET, SLC_CTRL(host->io_base));
243 	udelay(1000);
244 
245 	/* Basic setup */
246 	writel(0, SLC_CFG(host->io_base));
247 	writel(0, SLC_IEN(host->io_base));
248 	writel((SLCSTAT_INT_TC | SLCSTAT_INT_RDY_EN),
249 		SLC_ICR(host->io_base));
250 
251 	/* Get base clock for SLC block */
252 	clkrate = clk_get_rate(host->clk);
253 	if (clkrate == 0)
254 		clkrate = LPC32XX_DEF_BUS_RATE;
255 
256 	/* Compute clock setup values */
257 	tmp = SLCTAC_WDR(host->ncfg->wdr_clks) |
258 		SLCTAC_WWIDTH(clkrate, host->ncfg->wwidth) |
259 		SLCTAC_WHOLD(clkrate, host->ncfg->whold) |
260 		SLCTAC_WSETUP(clkrate, host->ncfg->wsetup) |
261 		SLCTAC_RDR(host->ncfg->rdr_clks) |
262 		SLCTAC_RWIDTH(clkrate, host->ncfg->rwidth) |
263 		SLCTAC_RHOLD(clkrate, host->ncfg->rhold) |
264 		SLCTAC_RSETUP(clkrate, host->ncfg->rsetup);
265 	writel(tmp, SLC_TAC(host->io_base));
266 }
267 
268 /*
269  * Hardware specific access to control lines
270  */
271 static void lpc32xx_nand_cmd_ctrl(struct nand_chip *chip, int cmd,
272 				  unsigned int ctrl)
273 {
274 	uint32_t tmp;
275 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
276 
277 	/* Does CE state need to be changed? */
278 	tmp = readl(SLC_CFG(host->io_base));
279 	if (ctrl & NAND_NCE)
280 		tmp |= SLCCFG_CE_LOW;
281 	else
282 		tmp &= ~SLCCFG_CE_LOW;
283 	writel(tmp, SLC_CFG(host->io_base));
284 
285 	if (cmd != NAND_CMD_NONE) {
286 		if (ctrl & NAND_CLE)
287 			writel(cmd, SLC_CMD(host->io_base));
288 		else
289 			writel(cmd, SLC_ADDR(host->io_base));
290 	}
291 }
292 
293 /*
294  * Read the Device Ready pin
295  */
296 static int lpc32xx_nand_device_ready(struct nand_chip *chip)
297 {
298 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
299 	int rdy = 0;
300 
301 	if ((readl(SLC_STAT(host->io_base)) & SLCSTAT_NAND_READY) != 0)
302 		rdy = 1;
303 
304 	return rdy;
305 }
306 
307 /*
308  * Enable NAND write protect
309  */
310 static void lpc32xx_wp_enable(struct lpc32xx_nand_host *host)
311 {
312 	if (gpio_is_valid(host->ncfg->wp_gpio))
313 		gpio_set_value(host->ncfg->wp_gpio, 0);
314 }
315 
316 /*
317  * Disable NAND write protect
318  */
319 static void lpc32xx_wp_disable(struct lpc32xx_nand_host *host)
320 {
321 	if (gpio_is_valid(host->ncfg->wp_gpio))
322 		gpio_set_value(host->ncfg->wp_gpio, 1);
323 }
324 
325 /*
326  * Prepares SLC for transfers with H/W ECC enabled
327  */
328 static void lpc32xx_nand_ecc_enable(struct nand_chip *chip, int mode)
329 {
330 	/* Hardware ECC is enabled automatically in hardware as needed */
331 }
332 
333 /*
334  * Calculates the ECC for the data
335  */
336 static int lpc32xx_nand_ecc_calculate(struct nand_chip *chip,
337 				      const unsigned char *buf,
338 				      unsigned char *code)
339 {
340 	/*
341 	 * ECC is calculated automatically in hardware during syndrome read
342 	 * and write operations, so it doesn't need to be calculated here.
343 	 */
344 	return 0;
345 }
346 
347 /*
348  * Read a single byte from NAND device
349  */
350 static uint8_t lpc32xx_nand_read_byte(struct nand_chip *chip)
351 {
352 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
353 
354 	return (uint8_t)readl(SLC_DATA(host->io_base));
355 }
356 
357 /*
358  * Simple device read without ECC
359  */
360 static void lpc32xx_nand_read_buf(struct nand_chip *chip, u_char *buf, int len)
361 {
362 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
363 
364 	/* Direct device read with no ECC */
365 	while (len-- > 0)
366 		*buf++ = (uint8_t)readl(SLC_DATA(host->io_base));
367 }
368 
369 /*
370  * Simple device write without ECC
371  */
372 static void lpc32xx_nand_write_buf(struct nand_chip *chip, const uint8_t *buf,
373 				   int len)
374 {
375 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
376 
377 	/* Direct device write with no ECC */
378 	while (len-- > 0)
379 		writel((uint32_t)*buf++, SLC_DATA(host->io_base));
380 }
381 
382 /*
383  * Read the OOB data from the device without ECC using FIFO method
384  */
385 static int lpc32xx_nand_read_oob_syndrome(struct nand_chip *chip, int page)
386 {
387 	struct mtd_info *mtd = nand_to_mtd(chip);
388 
389 	return nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
390 }
391 
392 /*
393  * Write the OOB data to the device without ECC using FIFO method
394  */
395 static int lpc32xx_nand_write_oob_syndrome(struct nand_chip *chip, int page)
396 {
397 	struct mtd_info *mtd = nand_to_mtd(chip);
398 
399 	return nand_prog_page_op(chip, page, mtd->writesize, chip->oob_poi,
400 				 mtd->oobsize);
401 }
402 
403 /*
404  * Fills in the ECC fields in the OOB buffer with the hardware generated ECC
405  */
406 static void lpc32xx_slc_ecc_copy(uint8_t *spare, const uint32_t *ecc, int count)
407 {
408 	int i;
409 
410 	for (i = 0; i < (count * 3); i += 3) {
411 		uint32_t ce = ecc[i / 3];
412 		ce = ~(ce << 2) & 0xFFFFFF;
413 		spare[i + 2] = (uint8_t)(ce & 0xFF);
414 		ce >>= 8;
415 		spare[i + 1] = (uint8_t)(ce & 0xFF);
416 		ce >>= 8;
417 		spare[i] = (uint8_t)(ce & 0xFF);
418 	}
419 }
420 
421 static void lpc32xx_dma_complete_func(void *completion)
422 {
423 	complete(completion);
424 }
425 
426 static int lpc32xx_xmit_dma(struct mtd_info *mtd, dma_addr_t dma,
427 			    void *mem, int len, enum dma_transfer_direction dir)
428 {
429 	struct nand_chip *chip = mtd_to_nand(mtd);
430 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
431 	struct dma_async_tx_descriptor *desc;
432 	int flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
433 	int res;
434 
435 	host->dma_slave_config.direction = dir;
436 	host->dma_slave_config.src_addr = dma;
437 	host->dma_slave_config.dst_addr = dma;
438 	host->dma_slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
439 	host->dma_slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
440 	host->dma_slave_config.src_maxburst = 4;
441 	host->dma_slave_config.dst_maxburst = 4;
442 	/* DMA controller does flow control: */
443 	host->dma_slave_config.device_fc = false;
444 	if (dmaengine_slave_config(host->dma_chan, &host->dma_slave_config)) {
445 		dev_err(mtd->dev.parent, "Failed to setup DMA slave\n");
446 		return -ENXIO;
447 	}
448 
449 	sg_init_one(&host->sgl, mem, len);
450 
451 	res = dma_map_sg(host->dma_chan->device->dev, &host->sgl, 1,
452 			 DMA_BIDIRECTIONAL);
453 	if (res != 1) {
454 		dev_err(mtd->dev.parent, "Failed to map sg list\n");
455 		return -ENXIO;
456 	}
457 	desc = dmaengine_prep_slave_sg(host->dma_chan, &host->sgl, 1, dir,
458 				       flags);
459 	if (!desc) {
460 		dev_err(mtd->dev.parent, "Failed to prepare slave sg\n");
461 		goto out1;
462 	}
463 
464 	init_completion(&host->comp);
465 	desc->callback = lpc32xx_dma_complete_func;
466 	desc->callback_param = &host->comp;
467 
468 	dmaengine_submit(desc);
469 	dma_async_issue_pending(host->dma_chan);
470 
471 	wait_for_completion_timeout(&host->comp, msecs_to_jiffies(1000));
472 
473 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
474 		     DMA_BIDIRECTIONAL);
475 
476 	return 0;
477 out1:
478 	dma_unmap_sg(host->dma_chan->device->dev, &host->sgl, 1,
479 		     DMA_BIDIRECTIONAL);
480 	return -ENXIO;
481 }
482 
483 /*
484  * DMA read/write transfers with ECC support
485  */
486 static int lpc32xx_xfer(struct mtd_info *mtd, uint8_t *buf, int eccsubpages,
487 			int read)
488 {
489 	struct nand_chip *chip = mtd_to_nand(mtd);
490 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
491 	int i, status = 0;
492 	unsigned long timeout;
493 	int res;
494 	enum dma_transfer_direction dir =
495 		read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
496 	uint8_t *dma_buf;
497 	bool dma_mapped;
498 
499 	if ((void *)buf <= high_memory) {
500 		dma_buf = buf;
501 		dma_mapped = true;
502 	} else {
503 		dma_buf = host->data_buf;
504 		dma_mapped = false;
505 		if (!read)
506 			memcpy(host->data_buf, buf, mtd->writesize);
507 	}
508 
509 	if (read) {
510 		writel(readl(SLC_CFG(host->io_base)) |
511 		       SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
512 		       SLCCFG_DMA_BURST, SLC_CFG(host->io_base));
513 	} else {
514 		writel((readl(SLC_CFG(host->io_base)) |
515 			SLCCFG_ECC_EN | SLCCFG_DMA_ECC | SLCCFG_DMA_BURST) &
516 		       ~SLCCFG_DMA_DIR,
517 			SLC_CFG(host->io_base));
518 	}
519 
520 	/* Clear initial ECC */
521 	writel(SLCCTRL_ECC_CLEAR, SLC_CTRL(host->io_base));
522 
523 	/* Transfer size is data area only */
524 	writel(mtd->writesize, SLC_TC(host->io_base));
525 
526 	/* Start transfer in the NAND controller */
527 	writel(readl(SLC_CTRL(host->io_base)) | SLCCTRL_DMA_START,
528 	       SLC_CTRL(host->io_base));
529 
530 	for (i = 0; i < chip->ecc.steps; i++) {
531 		/* Data */
532 		res = lpc32xx_xmit_dma(mtd, SLC_DMA_DATA(host->io_base_dma),
533 				       dma_buf + i * chip->ecc.size,
534 				       mtd->writesize / chip->ecc.steps, dir);
535 		if (res)
536 			return res;
537 
538 		/* Always _read_ ECC */
539 		if (i == chip->ecc.steps - 1)
540 			break;
541 		if (!read) /* ECC availability delayed on write */
542 			udelay(10);
543 		res = lpc32xx_xmit_dma(mtd, SLC_ECC(host->io_base_dma),
544 				       &host->ecc_buf[i], 4, DMA_DEV_TO_MEM);
545 		if (res)
546 			return res;
547 	}
548 
549 	/*
550 	 * According to NXP, the DMA can be finished here, but the NAND
551 	 * controller may still have buffered data. After porting to using the
552 	 * dmaengine DMA driver (amba-pl080), the condition (DMA_FIFO empty)
553 	 * appears to be always true, according to tests. Keeping the check for
554 	 * safety reasons for now.
555 	 */
556 	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) {
557 		dev_warn(mtd->dev.parent, "FIFO not empty!\n");
558 		timeout = jiffies + msecs_to_jiffies(LPC32XX_DMA_TIMEOUT);
559 		while ((readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO) &&
560 		       time_before(jiffies, timeout))
561 			cpu_relax();
562 		if (!time_before(jiffies, timeout)) {
563 			dev_err(mtd->dev.parent, "FIFO held data too long\n");
564 			status = -EIO;
565 		}
566 	}
567 
568 	/* Read last calculated ECC value */
569 	if (!read)
570 		udelay(10);
571 	host->ecc_buf[chip->ecc.steps - 1] =
572 		readl(SLC_ECC(host->io_base));
573 
574 	/* Flush DMA */
575 	dmaengine_terminate_all(host->dma_chan);
576 
577 	if (readl(SLC_STAT(host->io_base)) & SLCSTAT_DMA_FIFO ||
578 	    readl(SLC_TC(host->io_base))) {
579 		/* Something is left in the FIFO, something is wrong */
580 		dev_err(mtd->dev.parent, "DMA FIFO failure\n");
581 		status = -EIO;
582 	}
583 
584 	/* Stop DMA & HW ECC */
585 	writel(readl(SLC_CTRL(host->io_base)) & ~SLCCTRL_DMA_START,
586 	       SLC_CTRL(host->io_base));
587 	writel(readl(SLC_CFG(host->io_base)) &
588 	       ~(SLCCFG_DMA_DIR | SLCCFG_ECC_EN | SLCCFG_DMA_ECC |
589 		 SLCCFG_DMA_BURST), SLC_CFG(host->io_base));
590 
591 	if (!dma_mapped && read)
592 		memcpy(buf, host->data_buf, mtd->writesize);
593 
594 	return status;
595 }
596 
597 /*
598  * Read the data and OOB data from the device, use ECC correction with the
599  * data, disable ECC for the OOB data
600  */
601 static int lpc32xx_nand_read_page_syndrome(struct nand_chip *chip, uint8_t *buf,
602 					   int oob_required, int page)
603 {
604 	struct mtd_info *mtd = nand_to_mtd(chip);
605 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
606 	struct mtd_oob_region oobregion = { };
607 	int stat, i, status, error;
608 	uint8_t *oobecc, tmpecc[LPC32XX_ECC_SAVE_SIZE];
609 
610 	/* Issue read command */
611 	nand_read_page_op(chip, page, 0, NULL, 0);
612 
613 	/* Read data and oob, calculate ECC */
614 	status = lpc32xx_xfer(mtd, buf, chip->ecc.steps, 1);
615 
616 	/* Get OOB data */
617 	chip->legacy.read_buf(chip, chip->oob_poi, mtd->oobsize);
618 
619 	/* Convert to stored ECC format */
620 	lpc32xx_slc_ecc_copy(tmpecc, (uint32_t *) host->ecc_buf, chip->ecc.steps);
621 
622 	/* Pointer to ECC data retrieved from NAND spare area */
623 	error = mtd_ooblayout_ecc(mtd, 0, &oobregion);
624 	if (error)
625 		return error;
626 
627 	oobecc = chip->oob_poi + oobregion.offset;
628 
629 	for (i = 0; i < chip->ecc.steps; i++) {
630 		stat = chip->ecc.correct(chip, buf, oobecc,
631 					 &tmpecc[i * chip->ecc.bytes]);
632 		if (stat < 0)
633 			mtd->ecc_stats.failed++;
634 		else
635 			mtd->ecc_stats.corrected += stat;
636 
637 		buf += chip->ecc.size;
638 		oobecc += chip->ecc.bytes;
639 	}
640 
641 	return status;
642 }
643 
644 /*
645  * Read the data and OOB data from the device, no ECC correction with the
646  * data or OOB data
647  */
648 static int lpc32xx_nand_read_page_raw_syndrome(struct nand_chip *chip,
649 					       uint8_t *buf, int oob_required,
650 					       int page)
651 {
652 	struct mtd_info *mtd = nand_to_mtd(chip);
653 
654 	/* Issue read command */
655 	nand_read_page_op(chip, page, 0, NULL, 0);
656 
657 	/* Raw reads can just use the FIFO interface */
658 	chip->legacy.read_buf(chip, buf, chip->ecc.size * chip->ecc.steps);
659 	chip->legacy.read_buf(chip, chip->oob_poi, mtd->oobsize);
660 
661 	return 0;
662 }
663 
664 /*
665  * Write the data and OOB data to the device, use ECC with the data,
666  * disable ECC for the OOB data
667  */
668 static int lpc32xx_nand_write_page_syndrome(struct nand_chip *chip,
669 					    const uint8_t *buf,
670 					    int oob_required, int page)
671 {
672 	struct mtd_info *mtd = nand_to_mtd(chip);
673 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
674 	struct mtd_oob_region oobregion = { };
675 	uint8_t *pb;
676 	int error;
677 
678 	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
679 
680 	/* Write data, calculate ECC on outbound data */
681 	error = lpc32xx_xfer(mtd, (uint8_t *)buf, chip->ecc.steps, 0);
682 	if (error)
683 		return error;
684 
685 	/*
686 	 * The calculated ECC needs some manual work done to it before
687 	 * committing it to NAND. Process the calculated ECC and place
688 	 * the resultant values directly into the OOB buffer. */
689 	error = mtd_ooblayout_ecc(mtd, 0, &oobregion);
690 	if (error)
691 		return error;
692 
693 	pb = chip->oob_poi + oobregion.offset;
694 	lpc32xx_slc_ecc_copy(pb, (uint32_t *)host->ecc_buf, chip->ecc.steps);
695 
696 	/* Write ECC data to device */
697 	chip->legacy.write_buf(chip, chip->oob_poi, mtd->oobsize);
698 
699 	return nand_prog_page_end_op(chip);
700 }
701 
702 /*
703  * Write the data and OOB data to the device, no ECC correction with the
704  * data or OOB data
705  */
706 static int lpc32xx_nand_write_page_raw_syndrome(struct nand_chip *chip,
707 						const uint8_t *buf,
708 						int oob_required, int page)
709 {
710 	struct mtd_info *mtd = nand_to_mtd(chip);
711 
712 	/* Raw writes can just use the FIFO interface */
713 	nand_prog_page_begin_op(chip, page, 0, buf,
714 				chip->ecc.size * chip->ecc.steps);
715 	chip->legacy.write_buf(chip, chip->oob_poi, mtd->oobsize);
716 
717 	return nand_prog_page_end_op(chip);
718 }
719 
720 static int lpc32xx_nand_dma_setup(struct lpc32xx_nand_host *host)
721 {
722 	struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
723 	dma_cap_mask_t mask;
724 
725 	if (!host->pdata || !host->pdata->dma_filter) {
726 		dev_err(mtd->dev.parent, "no DMA platform data\n");
727 		return -ENOENT;
728 	}
729 
730 	dma_cap_zero(mask);
731 	dma_cap_set(DMA_SLAVE, mask);
732 	host->dma_chan = dma_request_channel(mask, host->pdata->dma_filter,
733 					     "nand-slc");
734 	if (!host->dma_chan) {
735 		dev_err(mtd->dev.parent, "Failed to request DMA channel\n");
736 		return -EBUSY;
737 	}
738 
739 	return 0;
740 }
741 
742 static struct lpc32xx_nand_cfg_slc *lpc32xx_parse_dt(struct device *dev)
743 {
744 	struct lpc32xx_nand_cfg_slc *ncfg;
745 	struct device_node *np = dev->of_node;
746 
747 	ncfg = devm_kzalloc(dev, sizeof(*ncfg), GFP_KERNEL);
748 	if (!ncfg)
749 		return NULL;
750 
751 	of_property_read_u32(np, "nxp,wdr-clks", &ncfg->wdr_clks);
752 	of_property_read_u32(np, "nxp,wwidth", &ncfg->wwidth);
753 	of_property_read_u32(np, "nxp,whold", &ncfg->whold);
754 	of_property_read_u32(np, "nxp,wsetup", &ncfg->wsetup);
755 	of_property_read_u32(np, "nxp,rdr-clks", &ncfg->rdr_clks);
756 	of_property_read_u32(np, "nxp,rwidth", &ncfg->rwidth);
757 	of_property_read_u32(np, "nxp,rhold", &ncfg->rhold);
758 	of_property_read_u32(np, "nxp,rsetup", &ncfg->rsetup);
759 
760 	if (!ncfg->wdr_clks || !ncfg->wwidth || !ncfg->whold ||
761 	    !ncfg->wsetup || !ncfg->rdr_clks || !ncfg->rwidth ||
762 	    !ncfg->rhold || !ncfg->rsetup) {
763 		dev_err(dev, "chip parameters not specified correctly\n");
764 		return NULL;
765 	}
766 
767 	ncfg->wp_gpio = of_get_named_gpio(np, "gpios", 0);
768 
769 	return ncfg;
770 }
771 
772 static int lpc32xx_nand_attach_chip(struct nand_chip *chip)
773 {
774 	struct mtd_info *mtd = nand_to_mtd(chip);
775 	struct lpc32xx_nand_host *host = nand_get_controller_data(chip);
776 
777 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
778 		return 0;
779 
780 	/* OOB and ECC CPU and DMA work areas */
781 	host->ecc_buf = (uint32_t *)(host->data_buf + LPC32XX_DMA_DATA_SIZE);
782 
783 	/*
784 	 * Small page FLASH has a unique OOB layout, but large and huge
785 	 * page FLASH use the standard layout. Small page FLASH uses a
786 	 * custom BBT marker layout.
787 	 */
788 	if (mtd->writesize <= 512)
789 		mtd_set_ooblayout(mtd, &lpc32xx_ooblayout_ops);
790 
791 	chip->ecc.placement = NAND_ECC_PLACEMENT_INTERLEAVED;
792 	/* These sizes remain the same regardless of page size */
793 	chip->ecc.size = 256;
794 	chip->ecc.strength = 1;
795 	chip->ecc.bytes = LPC32XX_SLC_DEV_ECC_BYTES;
796 	chip->ecc.prepad = 0;
797 	chip->ecc.postpad = 0;
798 	chip->ecc.read_page_raw = lpc32xx_nand_read_page_raw_syndrome;
799 	chip->ecc.read_page = lpc32xx_nand_read_page_syndrome;
800 	chip->ecc.write_page_raw = lpc32xx_nand_write_page_raw_syndrome;
801 	chip->ecc.write_page = lpc32xx_nand_write_page_syndrome;
802 	chip->ecc.write_oob = lpc32xx_nand_write_oob_syndrome;
803 	chip->ecc.read_oob = lpc32xx_nand_read_oob_syndrome;
804 	chip->ecc.calculate = lpc32xx_nand_ecc_calculate;
805 	chip->ecc.correct = rawnand_sw_hamming_correct;
806 	chip->ecc.hwctl = lpc32xx_nand_ecc_enable;
807 
808 	/*
809 	 * Use a custom BBT marker setup for small page FLASH that
810 	 * won't interfere with the ECC layout. Large and huge page
811 	 * FLASH use the standard layout.
812 	 */
813 	if ((chip->bbt_options & NAND_BBT_USE_FLASH) &&
814 	    mtd->writesize <= 512) {
815 		chip->bbt_td = &bbt_smallpage_main_descr;
816 		chip->bbt_md = &bbt_smallpage_mirror_descr;
817 	}
818 
819 	return 0;
820 }
821 
822 static const struct nand_controller_ops lpc32xx_nand_controller_ops = {
823 	.attach_chip = lpc32xx_nand_attach_chip,
824 };
825 
826 /*
827  * Probe for NAND controller
828  */
829 static int lpc32xx_nand_probe(struct platform_device *pdev)
830 {
831 	struct lpc32xx_nand_host *host;
832 	struct mtd_info *mtd;
833 	struct nand_chip *chip;
834 	struct resource *rc;
835 	int res;
836 
837 	/* Allocate memory for the device structure (and zero it) */
838 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
839 	if (!host)
840 		return -ENOMEM;
841 
842 	rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
843 	host->io_base = devm_ioremap_resource(&pdev->dev, 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 	if (host->ncfg->wp_gpio == -EPROBE_DEFER)
856 		return -EPROBE_DEFER;
857 	if (gpio_is_valid(host->ncfg->wp_gpio) && devm_gpio_request(&pdev->dev,
858 			host->ncfg->wp_gpio, "NAND WP")) {
859 		dev_err(&pdev->dev, "GPIO not available\n");
860 		return -EBUSY;
861 	}
862 	lpc32xx_wp_disable(host);
863 
864 	host->pdata = dev_get_platdata(&pdev->dev);
865 
866 	chip = &host->nand_chip;
867 	mtd = nand_to_mtd(chip);
868 	nand_set_controller_data(chip, host);
869 	nand_set_flash_node(chip, pdev->dev.of_node);
870 	mtd->owner = THIS_MODULE;
871 	mtd->dev.parent = &pdev->dev;
872 
873 	/* Get NAND clock */
874 	host->clk = devm_clk_get(&pdev->dev, NULL);
875 	if (IS_ERR(host->clk)) {
876 		dev_err(&pdev->dev, "Clock failure\n");
877 		res = -ENOENT;
878 		goto enable_wp;
879 	}
880 	res = clk_prepare_enable(host->clk);
881 	if (res)
882 		goto enable_wp;
883 
884 	/* Set NAND IO addresses and command/ready functions */
885 	chip->legacy.IO_ADDR_R = SLC_DATA(host->io_base);
886 	chip->legacy.IO_ADDR_W = SLC_DATA(host->io_base);
887 	chip->legacy.cmd_ctrl = lpc32xx_nand_cmd_ctrl;
888 	chip->legacy.dev_ready = lpc32xx_nand_device_ready;
889 	chip->legacy.chip_delay = 20; /* 20us command delay time */
890 
891 	/* Init NAND controller */
892 	lpc32xx_nand_setup(host);
893 
894 	platform_set_drvdata(pdev, host);
895 
896 	/* NAND callbacks for LPC32xx SLC hardware */
897 	chip->legacy.read_byte = lpc32xx_nand_read_byte;
898 	chip->legacy.read_buf = lpc32xx_nand_read_buf;
899 	chip->legacy.write_buf = lpc32xx_nand_write_buf;
900 
901 	/*
902 	 * Allocate a large enough buffer for a single huge page plus
903 	 * extra space for the spare area and ECC storage area
904 	 */
905 	host->dma_buf_len = LPC32XX_DMA_DATA_SIZE + LPC32XX_ECC_SAVE_SIZE;
906 	host->data_buf = devm_kzalloc(&pdev->dev, host->dma_buf_len,
907 				      GFP_KERNEL);
908 	if (host->data_buf == NULL) {
909 		res = -ENOMEM;
910 		goto unprepare_clk;
911 	}
912 
913 	res = lpc32xx_nand_dma_setup(host);
914 	if (res) {
915 		res = -EIO;
916 		goto unprepare_clk;
917 	}
918 
919 	/* Find NAND device */
920 	chip->legacy.dummy_controller.ops = &lpc32xx_nand_controller_ops;
921 	res = nand_scan(chip, 1);
922 	if (res)
923 		goto release_dma;
924 
925 	mtd->name = "nxp_lpc3220_slc";
926 	res = mtd_device_register(mtd, host->ncfg->parts,
927 				  host->ncfg->num_parts);
928 	if (res)
929 		goto cleanup_nand;
930 
931 	return 0;
932 
933 cleanup_nand:
934 	nand_cleanup(chip);
935 release_dma:
936 	dma_release_channel(host->dma_chan);
937 unprepare_clk:
938 	clk_disable_unprepare(host->clk);
939 enable_wp:
940 	lpc32xx_wp_enable(host);
941 
942 	return res;
943 }
944 
945 /*
946  * Remove NAND device.
947  */
948 static int lpc32xx_nand_remove(struct platform_device *pdev)
949 {
950 	uint32_t tmp;
951 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
952 	struct nand_chip *chip = &host->nand_chip;
953 	int ret;
954 
955 	ret = mtd_device_unregister(nand_to_mtd(chip));
956 	WARN_ON(ret);
957 	nand_cleanup(chip);
958 	dma_release_channel(host->dma_chan);
959 
960 	/* Force CE high */
961 	tmp = readl(SLC_CTRL(host->io_base));
962 	tmp &= ~SLCCFG_CE_LOW;
963 	writel(tmp, SLC_CTRL(host->io_base));
964 
965 	clk_disable_unprepare(host->clk);
966 	lpc32xx_wp_enable(host);
967 
968 	return 0;
969 }
970 
971 #ifdef CONFIG_PM
972 static int lpc32xx_nand_resume(struct platform_device *pdev)
973 {
974 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
975 	int ret;
976 
977 	/* Re-enable NAND clock */
978 	ret = clk_prepare_enable(host->clk);
979 	if (ret)
980 		return ret;
981 
982 	/* Fresh init of NAND controller */
983 	lpc32xx_nand_setup(host);
984 
985 	/* Disable write protect */
986 	lpc32xx_wp_disable(host);
987 
988 	return 0;
989 }
990 
991 static int lpc32xx_nand_suspend(struct platform_device *pdev, pm_message_t pm)
992 {
993 	uint32_t tmp;
994 	struct lpc32xx_nand_host *host = platform_get_drvdata(pdev);
995 
996 	/* Force CE high */
997 	tmp = readl(SLC_CTRL(host->io_base));
998 	tmp &= ~SLCCFG_CE_LOW;
999 	writel(tmp, SLC_CTRL(host->io_base));
1000 
1001 	/* Enable write protect for safety */
1002 	lpc32xx_wp_enable(host);
1003 
1004 	/* Disable clock */
1005 	clk_disable_unprepare(host->clk);
1006 
1007 	return 0;
1008 }
1009 
1010 #else
1011 #define lpc32xx_nand_resume NULL
1012 #define lpc32xx_nand_suspend NULL
1013 #endif
1014 
1015 static const struct of_device_id lpc32xx_nand_match[] = {
1016 	{ .compatible = "nxp,lpc3220-slc" },
1017 	{ /* sentinel */ },
1018 };
1019 MODULE_DEVICE_TABLE(of, lpc32xx_nand_match);
1020 
1021 static struct platform_driver lpc32xx_nand_driver = {
1022 	.probe		= lpc32xx_nand_probe,
1023 	.remove		= lpc32xx_nand_remove,
1024 	.resume		= lpc32xx_nand_resume,
1025 	.suspend	= lpc32xx_nand_suspend,
1026 	.driver		= {
1027 		.name	= LPC32XX_MODNAME,
1028 		.of_match_table = lpc32xx_nand_match,
1029 	},
1030 };
1031 
1032 module_platform_driver(lpc32xx_nand_driver);
1033 
1034 MODULE_LICENSE("GPL");
1035 MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
1036 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
1037 MODULE_DESCRIPTION("NAND driver for the NXP LPC32XX SLC controller");
1038