xref: /openbmc/u-boot/drivers/mtd/nand/raw/tegra_nand.c (revision 6c6add60)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2011 The Chromium OS Authors.
4  * (C) Copyright 2011 NVIDIA Corporation <www.nvidia.com>
5  * (C) Copyright 2006 Detlev Zundel, dzu@denx.de
6  * (C) Copyright 2006 DENX Software Engineering
7  */
8 
9 #include <common.h>
10 #include <asm/io.h>
11 #include <memalign.h>
12 #include <nand.h>
13 #include <asm/arch/clock.h>
14 #include <asm/arch/funcmux.h>
15 #include <asm/arch-tegra/clk_rst.h>
16 #include <linux/errno.h>
17 #include <asm/gpio.h>
18 #include <fdtdec.h>
19 #include <bouncebuf.h>
20 #include <dm.h>
21 #include "tegra_nand.h"
22 
23 DECLARE_GLOBAL_DATA_PTR;
24 
25 #define NAND_CMD_TIMEOUT_MS		10
26 
27 #define SKIPPED_SPARE_BYTES		4
28 
29 /* ECC bytes to be generated for tag data */
30 #define TAG_ECC_BYTES			4
31 
32 static const struct udevice_id tegra_nand_dt_ids[] = {
33 	{
34 		.compatible = "nvidia,tegra20-nand",
35 	},
36 	{ /* sentinel */ }
37 };
38 
39 /* 64 byte oob block info for large page (== 2KB) device
40  *
41  * OOB flash layout for Tegra with Reed-Solomon 4 symbol correct ECC:
42  *      Skipped bytes(4)
43  *      Main area Ecc(36)
44  *      Tag data(20)
45  *      Tag data Ecc(4)
46  *
47  * Yaffs2 will use 16 tag bytes.
48  */
49 static struct nand_ecclayout eccoob = {
50 	.eccbytes = 36,
51 	.eccpos = {
52 		4,  5,  6,  7,  8,  9,  10, 11, 12,
53 		13, 14, 15, 16, 17, 18, 19, 20, 21,
54 		22, 23, 24, 25, 26, 27, 28, 29, 30,
55 		31, 32, 33, 34, 35, 36, 37, 38, 39,
56 	},
57 	.oobavail = 20,
58 	.oobfree = {
59 			{
60 			.offset = 40,
61 			.length = 20,
62 			},
63 	}
64 };
65 
66 enum {
67 	ECC_OK,
68 	ECC_TAG_ERROR = 1 << 0,
69 	ECC_DATA_ERROR = 1 << 1
70 };
71 
72 /* Timing parameters */
73 enum {
74 	FDT_NAND_MAX_TRP_TREA,
75 	FDT_NAND_TWB,
76 	FDT_NAND_MAX_TCR_TAR_TRR,
77 	FDT_NAND_TWHR,
78 	FDT_NAND_MAX_TCS_TCH_TALS_TALH,
79 	FDT_NAND_TWH,
80 	FDT_NAND_TWP,
81 	FDT_NAND_TRH,
82 	FDT_NAND_TADL,
83 
84 	FDT_NAND_TIMING_COUNT
85 };
86 
87 /* Information about an attached NAND chip */
88 struct fdt_nand {
89 	struct nand_ctlr *reg;
90 	int enabled;		/* 1 to enable, 0 to disable */
91 	struct gpio_desc wp_gpio;	/* write-protect GPIO */
92 	s32 width;		/* bit width, normally 8 */
93 	u32 timing[FDT_NAND_TIMING_COUNT];
94 };
95 
96 struct nand_drv {
97 	struct nand_ctlr *reg;
98 	struct fdt_nand config;
99 };
100 
101 struct tegra_nand_info {
102 	struct udevice *dev;
103 	struct nand_drv nand_ctrl;
104 	struct nand_chip nand_chip;
105 };
106 
107 /**
108  * Wait for command completion
109  *
110  * @param reg	nand_ctlr structure
111  * @return
112  *	1 - Command completed
113  *	0 - Timeout
114  */
115 static int nand_waitfor_cmd_completion(struct nand_ctlr *reg)
116 {
117 	u32 reg_val;
118 	int running;
119 	int i;
120 
121 	for (i = 0; i < NAND_CMD_TIMEOUT_MS * 1000; i++) {
122 		if ((readl(&reg->command) & CMD_GO) ||
123 				!(readl(&reg->status) & STATUS_RBSY0) ||
124 				!(readl(&reg->isr) & ISR_IS_CMD_DONE)) {
125 			udelay(1);
126 			continue;
127 		}
128 		reg_val = readl(&reg->dma_mst_ctrl);
129 		/*
130 		 * If DMA_MST_CTRL_EN_A_ENABLE or DMA_MST_CTRL_EN_B_ENABLE
131 		 * is set, that means DMA engine is running.
132 		 *
133 		 * Then we have to wait until DMA_MST_CTRL_IS_DMA_DONE
134 		 * is cleared, indicating DMA transfer completion.
135 		 */
136 		running = reg_val & (DMA_MST_CTRL_EN_A_ENABLE |
137 				DMA_MST_CTRL_EN_B_ENABLE);
138 		if (!running || (reg_val & DMA_MST_CTRL_IS_DMA_DONE))
139 			return 1;
140 		udelay(1);
141 	}
142 	return 0;
143 }
144 
145 /**
146  * Read one byte from the chip
147  *
148  * @param mtd	MTD device structure
149  * @return	data byte
150  *
151  * Read function for 8bit bus-width
152  */
153 static uint8_t read_byte(struct mtd_info *mtd)
154 {
155 	struct nand_chip *chip = mtd_to_nand(mtd);
156 	struct nand_drv *info;
157 
158 	info = (struct nand_drv *)nand_get_controller_data(chip);
159 
160 	writel(CMD_GO | CMD_PIO | CMD_RX | CMD_CE0 | CMD_A_VALID,
161 	       &info->reg->command);
162 	if (!nand_waitfor_cmd_completion(info->reg))
163 		printf("Command timeout\n");
164 
165 	return (uint8_t)readl(&info->reg->resp);
166 }
167 
168 /**
169  * Read len bytes from the chip into a buffer
170  *
171  * @param mtd	MTD device structure
172  * @param buf	buffer to store data to
173  * @param len	number of bytes to read
174  *
175  * Read function for 8bit bus-width
176  */
177 static void read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
178 {
179 	int i, s;
180 	unsigned int reg;
181 	struct nand_chip *chip = mtd_to_nand(mtd);
182 	struct nand_drv *info = (struct nand_drv *)nand_get_controller_data(chip);
183 
184 	for (i = 0; i < len; i += 4) {
185 		s = (len - i) > 4 ? 4 : len - i;
186 		writel(CMD_PIO | CMD_RX | CMD_A_VALID | CMD_CE0 |
187 			((s - 1) << CMD_TRANS_SIZE_SHIFT) | CMD_GO,
188 			&info->reg->command);
189 		if (!nand_waitfor_cmd_completion(info->reg))
190 			puts("Command timeout during read_buf\n");
191 		reg = readl(&info->reg->resp);
192 		memcpy(buf + i, &reg, s);
193 	}
194 }
195 
196 /**
197  * Check NAND status to see if it is ready or not
198  *
199  * @param mtd	MTD device structure
200  * @return
201  *	1 - ready
202  *	0 - not ready
203  */
204 static int nand_dev_ready(struct mtd_info *mtd)
205 {
206 	struct nand_chip *chip = mtd_to_nand(mtd);
207 	int reg_val;
208 	struct nand_drv *info;
209 
210 	info = (struct nand_drv *)nand_get_controller_data(chip);
211 
212 	reg_val = readl(&info->reg->status);
213 	if (reg_val & STATUS_RBSY0)
214 		return 1;
215 	else
216 		return 0;
217 }
218 
219 /* Dummy implementation: we don't support multiple chips */
220 static void nand_select_chip(struct mtd_info *mtd, int chipnr)
221 {
222 	switch (chipnr) {
223 	case -1:
224 	case 0:
225 		break;
226 
227 	default:
228 		BUG();
229 	}
230 }
231 
232 /**
233  * Clear all interrupt status bits
234  *
235  * @param reg	nand_ctlr structure
236  */
237 static void nand_clear_interrupt_status(struct nand_ctlr *reg)
238 {
239 	u32 reg_val;
240 
241 	/* Clear interrupt status */
242 	reg_val = readl(&reg->isr);
243 	writel(reg_val, &reg->isr);
244 }
245 
246 /**
247  * Send command to NAND device
248  *
249  * @param mtd		MTD device structure
250  * @param command	the command to be sent
251  * @param column	the column address for this command, -1 if none
252  * @param page_addr	the page address for this command, -1 if none
253  */
254 static void nand_command(struct mtd_info *mtd, unsigned int command,
255 	int column, int page_addr)
256 {
257 	struct nand_chip *chip = mtd_to_nand(mtd);
258 	struct nand_drv *info;
259 
260 	info = (struct nand_drv *)nand_get_controller_data(chip);
261 
262 	/*
263 	 * Write out the command to the device.
264 	 *
265 	 * Only command NAND_CMD_RESET or NAND_CMD_READID will come
266 	 * here before mtd->writesize is initialized.
267 	 */
268 
269 	/* Emulate NAND_CMD_READOOB */
270 	if (command == NAND_CMD_READOOB) {
271 		assert(mtd->writesize != 0);
272 		column += mtd->writesize;
273 		command = NAND_CMD_READ0;
274 	}
275 
276 	/* Adjust columns for 16 bit bus-width */
277 	if (column != -1 && (chip->options & NAND_BUSWIDTH_16))
278 		column >>= 1;
279 
280 	nand_clear_interrupt_status(info->reg);
281 
282 	/* Stop DMA engine, clear DMA completion status */
283 	writel(DMA_MST_CTRL_EN_A_DISABLE
284 		| DMA_MST_CTRL_EN_B_DISABLE
285 		| DMA_MST_CTRL_IS_DMA_DONE,
286 		&info->reg->dma_mst_ctrl);
287 
288 	/*
289 	 * Program and erase have their own busy handlers
290 	 * status and sequential in needs no delay
291 	 */
292 	switch (command) {
293 	case NAND_CMD_READID:
294 		writel(NAND_CMD_READID, &info->reg->cmd_reg1);
295 		writel(column & 0xFF, &info->reg->addr_reg1);
296 		writel(CMD_GO | CMD_CLE | CMD_ALE | CMD_CE0,
297 		       &info->reg->command);
298 		break;
299 	case NAND_CMD_PARAM:
300 		writel(NAND_CMD_PARAM, &info->reg->cmd_reg1);
301 		writel(column & 0xFF, &info->reg->addr_reg1);
302 		writel(CMD_GO | CMD_CLE | CMD_ALE | CMD_CE0,
303 			&info->reg->command);
304 		break;
305 	case NAND_CMD_READ0:
306 		writel(NAND_CMD_READ0, &info->reg->cmd_reg1);
307 		writel(NAND_CMD_READSTART, &info->reg->cmd_reg2);
308 		writel((page_addr << 16) | (column & 0xFFFF),
309 			&info->reg->addr_reg1);
310 		writel(page_addr >> 16, &info->reg->addr_reg2);
311 		return;
312 	case NAND_CMD_SEQIN:
313 		writel(NAND_CMD_SEQIN, &info->reg->cmd_reg1);
314 		writel(NAND_CMD_PAGEPROG, &info->reg->cmd_reg2);
315 		writel((page_addr << 16) | (column & 0xFFFF),
316 			&info->reg->addr_reg1);
317 		writel(page_addr >> 16,
318 			&info->reg->addr_reg2);
319 		return;
320 	case NAND_CMD_PAGEPROG:
321 		return;
322 	case NAND_CMD_ERASE1:
323 		writel(NAND_CMD_ERASE1, &info->reg->cmd_reg1);
324 		writel(NAND_CMD_ERASE2, &info->reg->cmd_reg2);
325 		writel(page_addr, &info->reg->addr_reg1);
326 		writel(CMD_GO | CMD_CLE | CMD_ALE |
327 			CMD_SEC_CMD | CMD_CE0 | CMD_ALE_BYTES3,
328 			&info->reg->command);
329 		break;
330 	case NAND_CMD_ERASE2:
331 		return;
332 	case NAND_CMD_STATUS:
333 		writel(NAND_CMD_STATUS, &info->reg->cmd_reg1);
334 		writel(CMD_GO | CMD_CLE | CMD_PIO | CMD_RX
335 			| ((1 - 0) << CMD_TRANS_SIZE_SHIFT)
336 			| CMD_CE0,
337 			&info->reg->command);
338 		break;
339 	case NAND_CMD_RESET:
340 		writel(NAND_CMD_RESET, &info->reg->cmd_reg1);
341 		writel(CMD_GO | CMD_CLE | CMD_CE0,
342 			&info->reg->command);
343 		break;
344 	case NAND_CMD_RNDOUT:
345 	default:
346 		printf("%s: Unsupported command %d\n", __func__, command);
347 		return;
348 	}
349 	if (!nand_waitfor_cmd_completion(info->reg))
350 		printf("Command 0x%02X timeout\n", command);
351 }
352 
353 /**
354  * Check whether the pointed buffer are all 0xff (blank).
355  *
356  * @param buf	data buffer for blank check
357  * @param len	length of the buffer in byte
358  * @return
359  *	1 - blank
360  *	0 - non-blank
361  */
362 static int blank_check(u8 *buf, int len)
363 {
364 	int i;
365 
366 	for (i = 0; i < len; i++)
367 		if (buf[i] != 0xFF)
368 			return 0;
369 	return 1;
370 }
371 
372 /**
373  * After a DMA transfer for read, we call this function to see whether there
374  * is any uncorrectable error on the pointed data buffer or oob buffer.
375  *
376  * @param reg		nand_ctlr structure
377  * @param databuf	data buffer
378  * @param a_len		data buffer length
379  * @param oobbuf	oob buffer
380  * @param b_len		oob buffer length
381  * @return
382  *	ECC_OK - no ECC error or correctable ECC error
383  *	ECC_TAG_ERROR - uncorrectable tag ECC error
384  *	ECC_DATA_ERROR - uncorrectable data ECC error
385  *	ECC_DATA_ERROR + ECC_TAG_ERROR - uncorrectable data+tag ECC error
386  */
387 static int check_ecc_error(struct nand_ctlr *reg, u8 *databuf,
388 	int a_len, u8 *oobbuf, int b_len)
389 {
390 	int return_val = ECC_OK;
391 	u32 reg_val;
392 
393 	if (!(readl(&reg->isr) & ISR_IS_ECC_ERR))
394 		return ECC_OK;
395 
396 	/*
397 	 * Area A is used for the data block (databuf). Area B is used for
398 	 * the spare block (oobbuf)
399 	 */
400 	reg_val = readl(&reg->dec_status);
401 	if ((reg_val & DEC_STATUS_A_ECC_FAIL) && databuf) {
402 		reg_val = readl(&reg->bch_dec_status_buf);
403 		/*
404 		 * If uncorrectable error occurs on data area, then see whether
405 		 * they are all FF. If all are FF, it's a blank page.
406 		 * Not error.
407 		 */
408 		if ((reg_val & BCH_DEC_STATUS_FAIL_SEC_FLAG_MASK) &&
409 				!blank_check(databuf, a_len))
410 			return_val |= ECC_DATA_ERROR;
411 	}
412 
413 	if ((reg_val & DEC_STATUS_B_ECC_FAIL) && oobbuf) {
414 		reg_val = readl(&reg->bch_dec_status_buf);
415 		/*
416 		 * If uncorrectable error occurs on tag area, then see whether
417 		 * they are all FF. If all are FF, it's a blank page.
418 		 * Not error.
419 		 */
420 		if ((reg_val & BCH_DEC_STATUS_FAIL_TAG_MASK) &&
421 				!blank_check(oobbuf, b_len))
422 			return_val |= ECC_TAG_ERROR;
423 	}
424 
425 	return return_val;
426 }
427 
428 /**
429  * Set GO bit to send command to device
430  *
431  * @param reg	nand_ctlr structure
432  */
433 static void start_command(struct nand_ctlr *reg)
434 {
435 	u32 reg_val;
436 
437 	reg_val = readl(&reg->command);
438 	reg_val |= CMD_GO;
439 	writel(reg_val, &reg->command);
440 }
441 
442 /**
443  * Clear command GO bit, DMA GO bit, and DMA completion status
444  *
445  * @param reg	nand_ctlr structure
446  */
447 static void stop_command(struct nand_ctlr *reg)
448 {
449 	/* Stop command */
450 	writel(0, &reg->command);
451 
452 	/* Stop DMA engine and clear DMA completion status */
453 	writel(DMA_MST_CTRL_GO_DISABLE
454 		| DMA_MST_CTRL_IS_DMA_DONE,
455 		&reg->dma_mst_ctrl);
456 }
457 
458 /**
459  * Set up NAND bus width and page size
460  *
461  * @param info		nand_info structure
462  * @param *reg_val	address of reg_val
463  * @return 0 if ok, -1 on error
464  */
465 static int set_bus_width_page_size(struct mtd_info *our_mtd,
466 				   struct fdt_nand *config, u32 *reg_val)
467 {
468 	if (config->width == 8)
469 		*reg_val = CFG_BUS_WIDTH_8BIT;
470 	else if (config->width == 16)
471 		*reg_val = CFG_BUS_WIDTH_16BIT;
472 	else {
473 		debug("%s: Unsupported bus width %d\n", __func__,
474 		      config->width);
475 		return -1;
476 	}
477 
478 	if (our_mtd->writesize == 512)
479 		*reg_val |= CFG_PAGE_SIZE_512;
480 	else if (our_mtd->writesize == 2048)
481 		*reg_val |= CFG_PAGE_SIZE_2048;
482 	else if (our_mtd->writesize == 4096)
483 		*reg_val |= CFG_PAGE_SIZE_4096;
484 	else {
485 		debug("%s: Unsupported page size %d\n", __func__,
486 		      our_mtd->writesize);
487 		return -1;
488 	}
489 
490 	return 0;
491 }
492 
493 /**
494  * Page read/write function
495  *
496  * @param mtd		mtd info structure
497  * @param chip		nand chip info structure
498  * @param buf		data buffer
499  * @param page		page number
500  * @param with_ecc	1 to enable ECC, 0 to disable ECC
501  * @param is_writing	0 for read, 1 for write
502  * @return	0 when successfully completed
503  *		-EIO when command timeout
504  */
505 static int nand_rw_page(struct mtd_info *mtd, struct nand_chip *chip,
506 	uint8_t *buf, int page, int with_ecc, int is_writing)
507 {
508 	u32 reg_val;
509 	int tag_size;
510 	struct nand_oobfree *free = chip->ecc.layout->oobfree;
511 	/* 4*128=512 (byte) is the value that our HW can support. */
512 	ALLOC_CACHE_ALIGN_BUFFER(u32, tag_buf, 128);
513 	char *tag_ptr;
514 	struct nand_drv *info;
515 	struct fdt_nand *config;
516 	unsigned int bbflags;
517 	struct bounce_buffer bbstate, bbstate_oob;
518 
519 	if ((uintptr_t)buf & 0x03) {
520 		printf("buf %p has to be 4-byte aligned\n", buf);
521 		return -EINVAL;
522 	}
523 
524 	info = (struct nand_drv *)nand_get_controller_data(chip);
525 	config = &info->config;
526 	if (set_bus_width_page_size(mtd, config, &reg_val))
527 		return -EINVAL;
528 
529 	/* Need to be 4-byte aligned */
530 	tag_ptr = (char *)tag_buf;
531 
532 	stop_command(info->reg);
533 
534 	if (is_writing)
535 		bbflags = GEN_BB_READ;
536 	else
537 		bbflags = GEN_BB_WRITE;
538 
539 	bounce_buffer_start(&bbstate, (void *)buf, 1 << chip->page_shift,
540 			    bbflags);
541 	writel((1 << chip->page_shift) - 1, &info->reg->dma_cfg_a);
542 	writel(virt_to_phys(bbstate.bounce_buffer), &info->reg->data_block_ptr);
543 
544 	/* Set ECC selection, configure ECC settings */
545 	if (with_ecc) {
546 		if (is_writing)
547 			memcpy(tag_ptr, chip->oob_poi + free->offset,
548 			       chip->ecc.layout->oobavail + TAG_ECC_BYTES);
549 		tag_size = chip->ecc.layout->oobavail + TAG_ECC_BYTES;
550 		reg_val |= (CFG_SKIP_SPARE_SEL_4
551 			| CFG_SKIP_SPARE_ENABLE
552 			| CFG_HW_ECC_CORRECTION_ENABLE
553 			| CFG_ECC_EN_TAG_DISABLE
554 			| CFG_HW_ECC_SEL_RS
555 			| CFG_HW_ECC_ENABLE
556 			| CFG_TVAL4
557 			| (tag_size - 1));
558 
559 		if (!is_writing)
560 			tag_size += SKIPPED_SPARE_BYTES;
561 		bounce_buffer_start(&bbstate_oob, (void *)tag_ptr, tag_size,
562 				    bbflags);
563 	} else {
564 		tag_size = mtd->oobsize;
565 		reg_val |= (CFG_SKIP_SPARE_DISABLE
566 			| CFG_HW_ECC_CORRECTION_DISABLE
567 			| CFG_ECC_EN_TAG_DISABLE
568 			| CFG_HW_ECC_DISABLE
569 			| (tag_size - 1));
570 		bounce_buffer_start(&bbstate_oob, (void *)chip->oob_poi,
571 				    tag_size, bbflags);
572 	}
573 	writel(reg_val, &info->reg->config);
574 	writel(virt_to_phys(bbstate_oob.bounce_buffer), &info->reg->tag_ptr);
575 	writel(BCH_CONFIG_BCH_ECC_DISABLE, &info->reg->bch_config);
576 	writel(tag_size - 1, &info->reg->dma_cfg_b);
577 
578 	nand_clear_interrupt_status(info->reg);
579 
580 	reg_val = CMD_CLE | CMD_ALE
581 		| CMD_SEC_CMD
582 		| (CMD_ALE_BYTES5 << CMD_ALE_BYTE_SIZE_SHIFT)
583 		| CMD_A_VALID
584 		| CMD_B_VALID
585 		| (CMD_TRANS_SIZE_PAGE << CMD_TRANS_SIZE_SHIFT)
586 		| CMD_CE0;
587 	if (!is_writing)
588 		reg_val |= (CMD_AFT_DAT_DISABLE | CMD_RX);
589 	else
590 		reg_val |= (CMD_AFT_DAT_ENABLE | CMD_TX);
591 	writel(reg_val, &info->reg->command);
592 
593 	/* Setup DMA engine */
594 	reg_val = DMA_MST_CTRL_GO_ENABLE
595 		| DMA_MST_CTRL_BURST_8WORDS
596 		| DMA_MST_CTRL_EN_A_ENABLE
597 		| DMA_MST_CTRL_EN_B_ENABLE;
598 
599 	if (!is_writing)
600 		reg_val |= DMA_MST_CTRL_DIR_READ;
601 	else
602 		reg_val |= DMA_MST_CTRL_DIR_WRITE;
603 
604 	writel(reg_val, &info->reg->dma_mst_ctrl);
605 
606 	start_command(info->reg);
607 
608 	if (!nand_waitfor_cmd_completion(info->reg)) {
609 		if (!is_writing)
610 			printf("Read Page 0x%X timeout ", page);
611 		else
612 			printf("Write Page 0x%X timeout ", page);
613 		if (with_ecc)
614 			printf("with ECC");
615 		else
616 			printf("without ECC");
617 		printf("\n");
618 		return -EIO;
619 	}
620 
621 	bounce_buffer_stop(&bbstate_oob);
622 	bounce_buffer_stop(&bbstate);
623 
624 	if (with_ecc && !is_writing) {
625 		memcpy(chip->oob_poi, tag_ptr,
626 			SKIPPED_SPARE_BYTES);
627 		memcpy(chip->oob_poi + free->offset,
628 			tag_ptr + SKIPPED_SPARE_BYTES,
629 			chip->ecc.layout->oobavail);
630 		reg_val = (u32)check_ecc_error(info->reg, (u8 *)buf,
631 			1 << chip->page_shift,
632 			(u8 *)(tag_ptr + SKIPPED_SPARE_BYTES),
633 			chip->ecc.layout->oobavail);
634 		if (reg_val & ECC_TAG_ERROR)
635 			printf("Read Page 0x%X tag ECC error\n", page);
636 		if (reg_val & ECC_DATA_ERROR)
637 			printf("Read Page 0x%X data ECC error\n",
638 				page);
639 		if (reg_val & (ECC_DATA_ERROR | ECC_TAG_ERROR))
640 			return -EIO;
641 	}
642 	return 0;
643 }
644 
645 /**
646  * Hardware ecc based page read function
647  *
648  * @param mtd	mtd info structure
649  * @param chip	nand chip info structure
650  * @param buf	buffer to store read data
651  * @param page	page number to read
652  * @return	0 when successfully completed
653  *		-EIO when command timeout
654  */
655 static int nand_read_page_hwecc(struct mtd_info *mtd,
656 	struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
657 {
658 	return nand_rw_page(mtd, chip, buf, page, 1, 0);
659 }
660 
661 /**
662  * Hardware ecc based page write function
663  *
664  * @param mtd	mtd info structure
665  * @param chip	nand chip info structure
666  * @param buf	data buffer
667  */
668 static int nand_write_page_hwecc(struct mtd_info *mtd,
669 	struct nand_chip *chip, const uint8_t *buf, int oob_required,
670 	int page)
671 {
672 	nand_rw_page(mtd, chip, (uint8_t *)buf, page, 1, 1);
673 	return 0;
674 }
675 
676 
677 /**
678  * Read raw page data without ecc
679  *
680  * @param mtd	mtd info structure
681  * @param chip	nand chip info structure
682  * @param buf	buffer to store read data
683  * @param page	page number to read
684  * @return	0 when successfully completed
685  *		-EINVAL when chip->oob_poi is not double-word aligned
686  *		-EIO when command timeout
687  */
688 static int nand_read_page_raw(struct mtd_info *mtd,
689 	struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
690 {
691 	return nand_rw_page(mtd, chip, buf, page, 0, 0);
692 }
693 
694 /**
695  * Raw page write function
696  *
697  * @param mtd	mtd info structure
698  * @param chip	nand chip info structure
699  * @param buf	data buffer
700  */
701 static int nand_write_page_raw(struct mtd_info *mtd,
702 		struct nand_chip *chip,	const uint8_t *buf,
703 		int oob_required, int page)
704 {
705 	nand_rw_page(mtd, chip, (uint8_t *)buf, page, 0, 1);
706 	return 0;
707 }
708 
709 /**
710  * OOB data read/write function
711  *
712  * @param mtd		mtd info structure
713  * @param chip		nand chip info structure
714  * @param page		page number to read
715  * @param with_ecc	1 to enable ECC, 0 to disable ECC
716  * @param is_writing	0 for read, 1 for write
717  * @return	0 when successfully completed
718  *		-EINVAL when chip->oob_poi is not double-word aligned
719  *		-EIO when command timeout
720  */
721 static int nand_rw_oob(struct mtd_info *mtd, struct nand_chip *chip,
722 	int page, int with_ecc, int is_writing)
723 {
724 	u32 reg_val;
725 	int tag_size;
726 	struct nand_oobfree *free = chip->ecc.layout->oobfree;
727 	struct nand_drv *info;
728 	unsigned int bbflags;
729 	struct bounce_buffer bbstate_oob;
730 
731 	if (((int)chip->oob_poi) & 0x03)
732 		return -EINVAL;
733 	info = (struct nand_drv *)nand_get_controller_data(chip);
734 	if (set_bus_width_page_size(mtd, &info->config, &reg_val))
735 		return -EINVAL;
736 
737 	stop_command(info->reg);
738 
739 	/* Set ECC selection */
740 	tag_size = mtd->oobsize;
741 	if (with_ecc)
742 		reg_val |= CFG_ECC_EN_TAG_ENABLE;
743 	else
744 		reg_val |= (CFG_ECC_EN_TAG_DISABLE);
745 
746 	reg_val |= ((tag_size - 1) |
747 		CFG_SKIP_SPARE_DISABLE |
748 		CFG_HW_ECC_CORRECTION_DISABLE |
749 		CFG_HW_ECC_DISABLE);
750 	writel(reg_val, &info->reg->config);
751 
752 	if (is_writing && with_ecc)
753 		tag_size -= TAG_ECC_BYTES;
754 
755 	if (is_writing)
756 		bbflags = GEN_BB_READ;
757 	else
758 		bbflags = GEN_BB_WRITE;
759 
760 	bounce_buffer_start(&bbstate_oob, (void *)chip->oob_poi, tag_size,
761 			    bbflags);
762 	writel(virt_to_phys(bbstate_oob.bounce_buffer), &info->reg->tag_ptr);
763 
764 	writel(BCH_CONFIG_BCH_ECC_DISABLE, &info->reg->bch_config);
765 
766 	writel(tag_size - 1, &info->reg->dma_cfg_b);
767 
768 	nand_clear_interrupt_status(info->reg);
769 
770 	reg_val = CMD_CLE | CMD_ALE
771 		| CMD_SEC_CMD
772 		| (CMD_ALE_BYTES5 << CMD_ALE_BYTE_SIZE_SHIFT)
773 		| CMD_B_VALID
774 		| CMD_CE0;
775 	if (!is_writing)
776 		reg_val |= (CMD_AFT_DAT_DISABLE | CMD_RX);
777 	else
778 		reg_val |= (CMD_AFT_DAT_ENABLE | CMD_TX);
779 	writel(reg_val, &info->reg->command);
780 
781 	/* Setup DMA engine */
782 	reg_val = DMA_MST_CTRL_GO_ENABLE
783 		| DMA_MST_CTRL_BURST_8WORDS
784 		| DMA_MST_CTRL_EN_B_ENABLE;
785 	if (!is_writing)
786 		reg_val |= DMA_MST_CTRL_DIR_READ;
787 	else
788 		reg_val |= DMA_MST_CTRL_DIR_WRITE;
789 
790 	writel(reg_val, &info->reg->dma_mst_ctrl);
791 
792 	start_command(info->reg);
793 
794 	if (!nand_waitfor_cmd_completion(info->reg)) {
795 		if (!is_writing)
796 			printf("Read OOB of Page 0x%X timeout\n", page);
797 		else
798 			printf("Write OOB of Page 0x%X timeout\n", page);
799 		return -EIO;
800 	}
801 
802 	bounce_buffer_stop(&bbstate_oob);
803 
804 	if (with_ecc && !is_writing) {
805 		reg_val = (u32)check_ecc_error(info->reg, 0, 0,
806 			(u8 *)(chip->oob_poi + free->offset),
807 			chip->ecc.layout->oobavail);
808 		if (reg_val & ECC_TAG_ERROR)
809 			printf("Read OOB of Page 0x%X tag ECC error\n", page);
810 	}
811 	return 0;
812 }
813 
814 /**
815  * OOB data read function
816  *
817  * @param mtd		mtd info structure
818  * @param chip		nand chip info structure
819  * @param page		page number to read
820  */
821 static int nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
822 	int page)
823 {
824 	chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
825 	nand_rw_oob(mtd, chip, page, 0, 0);
826 	return 0;
827 }
828 
829 /**
830  * OOB data write function
831  *
832  * @param mtd	mtd info structure
833  * @param chip	nand chip info structure
834  * @param page	page number to write
835  * @return	0 when successfully completed
836  *		-EINVAL when chip->oob_poi is not double-word aligned
837  *		-EIO when command timeout
838  */
839 static int nand_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
840 	int page)
841 {
842 	chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
843 
844 	return nand_rw_oob(mtd, chip, page, 0, 1);
845 }
846 
847 /**
848  * Set up NAND memory timings according to the provided parameters
849  *
850  * @param timing	Timing parameters
851  * @param reg		NAND controller register address
852  */
853 static void setup_timing(unsigned timing[FDT_NAND_TIMING_COUNT],
854 			 struct nand_ctlr *reg)
855 {
856 	u32 reg_val, clk_rate, clk_period, time_val;
857 
858 	clk_rate = (u32)clock_get_periph_rate(PERIPH_ID_NDFLASH,
859 		CLOCK_ID_PERIPH) / 1000000;
860 	clk_period = 1000 / clk_rate;
861 	reg_val = ((timing[FDT_NAND_MAX_TRP_TREA] / clk_period) <<
862 		TIMING_TRP_RESP_CNT_SHIFT) & TIMING_TRP_RESP_CNT_MASK;
863 	reg_val |= ((timing[FDT_NAND_TWB] / clk_period) <<
864 		TIMING_TWB_CNT_SHIFT) & TIMING_TWB_CNT_MASK;
865 	time_val = timing[FDT_NAND_MAX_TCR_TAR_TRR] / clk_period;
866 	if (time_val > 2)
867 		reg_val |= ((time_val - 2) << TIMING_TCR_TAR_TRR_CNT_SHIFT) &
868 			TIMING_TCR_TAR_TRR_CNT_MASK;
869 	reg_val |= ((timing[FDT_NAND_TWHR] / clk_period) <<
870 		TIMING_TWHR_CNT_SHIFT) & TIMING_TWHR_CNT_MASK;
871 	time_val = timing[FDT_NAND_MAX_TCS_TCH_TALS_TALH] / clk_period;
872 	if (time_val > 1)
873 		reg_val |= ((time_val - 1) << TIMING_TCS_CNT_SHIFT) &
874 			TIMING_TCS_CNT_MASK;
875 	reg_val |= ((timing[FDT_NAND_TWH] / clk_period) <<
876 		TIMING_TWH_CNT_SHIFT) & TIMING_TWH_CNT_MASK;
877 	reg_val |= ((timing[FDT_NAND_TWP] / clk_period) <<
878 		TIMING_TWP_CNT_SHIFT) & TIMING_TWP_CNT_MASK;
879 	reg_val |= ((timing[FDT_NAND_TRH] / clk_period) <<
880 		TIMING_TRH_CNT_SHIFT) & TIMING_TRH_CNT_MASK;
881 	reg_val |= ((timing[FDT_NAND_MAX_TRP_TREA] / clk_period) <<
882 		TIMING_TRP_CNT_SHIFT) & TIMING_TRP_CNT_MASK;
883 	writel(reg_val, &reg->timing);
884 
885 	reg_val = 0;
886 	time_val = timing[FDT_NAND_TADL] / clk_period;
887 	if (time_val > 2)
888 		reg_val = (time_val - 2) & TIMING2_TADL_CNT_MASK;
889 	writel(reg_val, &reg->timing2);
890 }
891 
892 /**
893  * Decode NAND parameters from the device tree
894  *
895  * @param dev		Driver model device
896  * @param config	Device tree NAND configuration
897  * @return 0 if ok, -ve on error (FDT_ERR_...)
898  */
899 static int fdt_decode_nand(struct udevice *dev, struct fdt_nand *config)
900 {
901 	int err;
902 
903 	config->reg = (struct nand_ctlr *)dev_read_addr(dev);
904 	config->enabled = dev_read_enabled(dev);
905 	config->width = dev_read_u32_default(dev, "nvidia,nand-width", 8);
906 	err = gpio_request_by_name(dev, "nvidia,wp-gpios", 0, &config->wp_gpio,
907 				   GPIOD_IS_OUT);
908 	if (err)
909 		return err;
910 	err = dev_read_u32_array(dev, "nvidia,timing", config->timing,
911 				 FDT_NAND_TIMING_COUNT);
912 	if (err < 0)
913 		return err;
914 
915 	return 0;
916 }
917 
918 static int tegra_probe(struct udevice *dev)
919 {
920 	struct tegra_nand_info *tegra = dev_get_priv(dev);
921 	struct nand_chip *nand = &tegra->nand_chip;
922 	struct nand_drv *info = &tegra->nand_ctrl;
923 	struct fdt_nand *config = &info->config;
924 	struct mtd_info *our_mtd;
925 	int ret;
926 
927 	if (fdt_decode_nand(dev, config)) {
928 		printf("Could not decode nand-flash in device tree\n");
929 		return -1;
930 	}
931 	if (!config->enabled)
932 		return -1;
933 	info->reg = config->reg;
934 	nand->ecc.mode = NAND_ECC_HW;
935 	nand->ecc.layout = &eccoob;
936 
937 	nand->options = LP_OPTIONS;
938 	nand->cmdfunc = nand_command;
939 	nand->read_byte = read_byte;
940 	nand->read_buf = read_buf;
941 	nand->ecc.read_page = nand_read_page_hwecc;
942 	nand->ecc.write_page = nand_write_page_hwecc;
943 	nand->ecc.read_page_raw = nand_read_page_raw;
944 	nand->ecc.write_page_raw = nand_write_page_raw;
945 	nand->ecc.read_oob = nand_read_oob;
946 	nand->ecc.write_oob = nand_write_oob;
947 	nand->ecc.strength = 1;
948 	nand->select_chip = nand_select_chip;
949 	nand->dev_ready  = nand_dev_ready;
950 	nand_set_controller_data(nand, &tegra->nand_ctrl);
951 
952 	/* Disable subpage writes as we do not provide ecc->hwctl */
953 	nand->options |= NAND_NO_SUBPAGE_WRITE;
954 
955 	/* Adjust controller clock rate */
956 	clock_start_periph_pll(PERIPH_ID_NDFLASH, CLOCK_ID_PERIPH, 52000000);
957 
958 	/* Adjust timing for NAND device */
959 	setup_timing(config->timing, info->reg);
960 
961 	dm_gpio_set_value(&config->wp_gpio, 1);
962 
963 	our_mtd = nand_to_mtd(nand);
964 	ret = nand_scan_ident(our_mtd, CONFIG_SYS_NAND_MAX_CHIPS, NULL);
965 	if (ret)
966 		return ret;
967 
968 	nand->ecc.size = our_mtd->writesize;
969 	nand->ecc.bytes = our_mtd->oobsize;
970 
971 	ret = nand_scan_tail(our_mtd);
972 	if (ret)
973 		return ret;
974 
975 	ret = nand_register(0, our_mtd);
976 	if (ret) {
977 		dev_err(dev, "Failed to register MTD: %d\n", ret);
978 		return ret;
979 	}
980 
981 	return 0;
982 }
983 
984 U_BOOT_DRIVER(tegra_nand) = {
985 	.name = "tegra-nand",
986 	.id = UCLASS_MTD,
987 	.of_match = tegra_nand_dt_ids,
988 	.probe = tegra_probe,
989 	.priv_auto_alloc_size = sizeof(struct tegra_nand_info),
990 };
991 
992 void board_nand_init(void)
993 {
994 	struct udevice *dev;
995 	int ret;
996 
997 	ret = uclass_get_device_by_driver(UCLASS_MTD,
998 					  DM_GET_DRIVER(tegra_nand), &dev);
999 	if (ret && ret != -ENODEV)
1000 		pr_err("Failed to initialize %s. (error %d)\n", dev->name,
1001 		       ret);
1002 }
1003