xref: /openbmc/u-boot/drivers/mtd/nand/raw/sunxi_nand_spl.c (revision 592cd5defd4f71d34ffcbd8dd3326bc10f662e20)
1  // SPDX-License-Identifier: GPL-2.0+
2  /*
3   * Copyright (c) 2014-2015, Antmicro Ltd <www.antmicro.com>
4   * Copyright (c) 2015, AW-SOM Technologies <www.aw-som.com>
5   */
6  
7  #include <asm/arch/clock.h>
8  #include <asm/io.h>
9  #include <common.h>
10  #include <config.h>
11  #include <nand.h>
12  #include <linux/ctype.h>
13  
14  /* registers */
15  #define NFC_CTL                    0x00000000
16  #define NFC_ST                     0x00000004
17  #define NFC_INT                    0x00000008
18  #define NFC_TIMING_CTL             0x0000000C
19  #define NFC_TIMING_CFG             0x00000010
20  #define NFC_ADDR_LOW               0x00000014
21  #define NFC_ADDR_HIGH              0x00000018
22  #define NFC_SECTOR_NUM             0x0000001C
23  #define NFC_CNT                    0x00000020
24  #define NFC_CMD                    0x00000024
25  #define NFC_RCMD_SET               0x00000028
26  #define NFC_WCMD_SET               0x0000002C
27  #define NFC_IO_DATA                0x00000030
28  #define NFC_ECC_CTL                0x00000034
29  #define NFC_ECC_ST                 0x00000038
30  #define NFC_DEBUG                  0x0000003C
31  #define NFC_ECC_CNT0               0x00000040
32  #define NFC_ECC_CNT1               0x00000044
33  #define NFC_ECC_CNT2               0x00000048
34  #define NFC_ECC_CNT3               0x0000004C
35  #define NFC_USER_DATA_BASE         0x00000050
36  #define NFC_EFNAND_STATUS          0x00000090
37  #define NFC_SPARE_AREA             0x000000A0
38  #define NFC_PATTERN_ID             0x000000A4
39  #define NFC_RAM0_BASE              0x00000400
40  #define NFC_RAM1_BASE              0x00000800
41  
42  #define NFC_CTL_EN                 (1 << 0)
43  #define NFC_CTL_RESET              (1 << 1)
44  #define NFC_CTL_RAM_METHOD         (1 << 14)
45  #define NFC_CTL_PAGE_SIZE_MASK     (0xf << 8)
46  #define NFC_CTL_PAGE_SIZE(a)       ((fls(a) - 11) << 8)
47  
48  
49  #define NFC_ECC_EN                 (1 << 0)
50  #define NFC_ECC_PIPELINE           (1 << 3)
51  #define NFC_ECC_EXCEPTION          (1 << 4)
52  #define NFC_ECC_BLOCK_SIZE         (1 << 5)
53  #define NFC_ECC_RANDOM_EN          (1 << 9)
54  #define NFC_ECC_RANDOM_DIRECTION   (1 << 10)
55  
56  
57  #define NFC_ADDR_NUM_OFFSET        16
58  #define NFC_SEND_ADDR              (1 << 19)
59  #define NFC_ACCESS_DIR             (1 << 20)
60  #define NFC_DATA_TRANS             (1 << 21)
61  #define NFC_SEND_CMD1              (1 << 22)
62  #define NFC_WAIT_FLAG              (1 << 23)
63  #define NFC_SEND_CMD2              (1 << 24)
64  #define NFC_SEQ                    (1 << 25)
65  #define NFC_DATA_SWAP_METHOD       (1 << 26)
66  #define NFC_ROW_AUTO_INC           (1 << 27)
67  #define NFC_SEND_CMD3              (1 << 28)
68  #define NFC_SEND_CMD4              (1 << 29)
69  #define NFC_RAW_CMD                (0 << 30)
70  #define NFC_ECC_CMD                (1 << 30)
71  #define NFC_PAGE_CMD               (2 << 30)
72  
73  #define NFC_ST_CMD_INT_FLAG        (1 << 1)
74  #define NFC_ST_DMA_INT_FLAG        (1 << 2)
75  #define NFC_ST_CMD_FIFO_STAT       (1 << 3)
76  
77  #define NFC_READ_CMD_OFFSET         0
78  #define NFC_RANDOM_READ_CMD0_OFFSET 8
79  #define NFC_RANDOM_READ_CMD1_OFFSET 16
80  
81  #define NFC_CMD_RNDOUTSTART        0xE0
82  #define NFC_CMD_RNDOUT             0x05
83  #define NFC_CMD_READSTART          0x30
84  
85  struct nfc_config {
86  	int page_size;
87  	int ecc_strength;
88  	int ecc_size;
89  	int addr_cycles;
90  	int nseeds;
91  	bool randomize;
92  	bool valid;
93  };
94  
95  /* minimal "boot0" style NAND support for Allwinner A20 */
96  
97  /* random seed used by linux */
98  const uint16_t random_seed[128] = {
99  	0x2b75, 0x0bd0, 0x5ca3, 0x62d1, 0x1c93, 0x07e9, 0x2162, 0x3a72,
100  	0x0d67, 0x67f9, 0x1be7, 0x077d, 0x032f, 0x0dac, 0x2716, 0x2436,
101  	0x7922, 0x1510, 0x3860, 0x5287, 0x480f, 0x4252, 0x1789, 0x5a2d,
102  	0x2a49, 0x5e10, 0x437f, 0x4b4e, 0x2f45, 0x216e, 0x5cb7, 0x7130,
103  	0x2a3f, 0x60e4, 0x4dc9, 0x0ef0, 0x0f52, 0x1bb9, 0x6211, 0x7a56,
104  	0x226d, 0x4ea7, 0x6f36, 0x3692, 0x38bf, 0x0c62, 0x05eb, 0x4c55,
105  	0x60f4, 0x728c, 0x3b6f, 0x2037, 0x7f69, 0x0936, 0x651a, 0x4ceb,
106  	0x6218, 0x79f3, 0x383f, 0x18d9, 0x4f05, 0x5c82, 0x2912, 0x6f17,
107  	0x6856, 0x5938, 0x1007, 0x61ab, 0x3e7f, 0x57c2, 0x542f, 0x4f62,
108  	0x7454, 0x2eac, 0x7739, 0x42d4, 0x2f90, 0x435a, 0x2e52, 0x2064,
109  	0x637c, 0x66ad, 0x2c90, 0x0bad, 0x759c, 0x0029, 0x0986, 0x7126,
110  	0x1ca7, 0x1605, 0x386a, 0x27f5, 0x1380, 0x6d75, 0x24c3, 0x0f8e,
111  	0x2b7a, 0x1418, 0x1fd1, 0x7dc1, 0x2d8e, 0x43af, 0x2267, 0x7da3,
112  	0x4e3d, 0x1338, 0x50db, 0x454d, 0x764d, 0x40a3, 0x42e6, 0x262b,
113  	0x2d2e, 0x1aea, 0x2e17, 0x173d, 0x3a6e, 0x71bf, 0x25f9, 0x0a5d,
114  	0x7c57, 0x0fbe, 0x46ce, 0x4939, 0x6b17, 0x37bb, 0x3e91, 0x76db,
115  };
116  
117  #define DEFAULT_TIMEOUT_US	100000
118  
check_value_inner(int offset,int expected_bits,int timeout_us,int negation)119  static int check_value_inner(int offset, int expected_bits,
120  			     int timeout_us, int negation)
121  {
122  	do {
123  		int val = readl(offset) & expected_bits;
124  		if (negation ? !val : val)
125  			return 1;
126  		udelay(1);
127  	} while (--timeout_us);
128  
129  	return 0;
130  }
131  
check_value(int offset,int expected_bits,int timeout_us)132  static inline int check_value(int offset, int expected_bits,
133  			      int timeout_us)
134  {
135  	return check_value_inner(offset, expected_bits, timeout_us, 0);
136  }
137  
check_value_negated(int offset,int unexpected_bits,int timeout_us)138  static inline int check_value_negated(int offset, int unexpected_bits,
139  				      int timeout_us)
140  {
141  	return check_value_inner(offset, unexpected_bits, timeout_us, 1);
142  }
143  
nand_wait_cmd_fifo_empty(void)144  static int nand_wait_cmd_fifo_empty(void)
145  {
146  	if (!check_value_negated(SUNXI_NFC_BASE + NFC_ST, NFC_ST_CMD_FIFO_STAT,
147  				 DEFAULT_TIMEOUT_US)) {
148  		printf("nand: timeout waiting for empty cmd FIFO\n");
149  		return -ETIMEDOUT;
150  	}
151  
152  	return 0;
153  }
154  
nand_wait_int(void)155  static int nand_wait_int(void)
156  {
157  	if (!check_value(SUNXI_NFC_BASE + NFC_ST, NFC_ST_CMD_INT_FLAG,
158  			 DEFAULT_TIMEOUT_US)) {
159  		printf("nand: timeout waiting for interruption\n");
160  		return -ETIMEDOUT;
161  	}
162  
163  	return 0;
164  }
165  
nand_exec_cmd(u32 cmd)166  static int nand_exec_cmd(u32 cmd)
167  {
168  	int ret;
169  
170  	ret = nand_wait_cmd_fifo_empty();
171  	if (ret)
172  		return ret;
173  
174  	writel(NFC_ST_CMD_INT_FLAG, SUNXI_NFC_BASE + NFC_ST);
175  	writel(cmd, SUNXI_NFC_BASE + NFC_CMD);
176  
177  	return nand_wait_int();
178  }
179  
nand_init(void)180  void nand_init(void)
181  {
182  	uint32_t val;
183  
184  	board_nand_init();
185  
186  	val = readl(SUNXI_NFC_BASE + NFC_CTL);
187  	/* enable and reset CTL */
188  	writel(val | NFC_CTL_EN | NFC_CTL_RESET,
189  	       SUNXI_NFC_BASE + NFC_CTL);
190  
191  	if (!check_value_negated(SUNXI_NFC_BASE + NFC_CTL,
192  				 NFC_CTL_RESET, DEFAULT_TIMEOUT_US)) {
193  		printf("Couldn't initialize nand\n");
194  	}
195  
196  	/* reset NAND */
197  	nand_exec_cmd(NFC_SEND_CMD1 | NFC_WAIT_FLAG | NAND_CMD_RESET);
198  }
199  
nand_apply_config(const struct nfc_config * conf)200  static void nand_apply_config(const struct nfc_config *conf)
201  {
202  	u32 val;
203  
204  	nand_wait_cmd_fifo_empty();
205  
206  	val = readl(SUNXI_NFC_BASE + NFC_CTL);
207  	val &= ~NFC_CTL_PAGE_SIZE_MASK;
208  	writel(val | NFC_CTL_RAM_METHOD | NFC_CTL_PAGE_SIZE(conf->page_size),
209  	       SUNXI_NFC_BASE + NFC_CTL);
210  	writel(conf->ecc_size, SUNXI_NFC_BASE + NFC_CNT);
211  	writel(conf->page_size, SUNXI_NFC_BASE + NFC_SPARE_AREA);
212  }
213  
nand_load_page(const struct nfc_config * conf,u32 offs)214  static int nand_load_page(const struct nfc_config *conf, u32 offs)
215  {
216  	int page = offs / conf->page_size;
217  
218  	writel((NFC_CMD_RNDOUTSTART << NFC_RANDOM_READ_CMD1_OFFSET) |
219  	       (NFC_CMD_RNDOUT << NFC_RANDOM_READ_CMD0_OFFSET) |
220  	       (NFC_CMD_READSTART << NFC_READ_CMD_OFFSET),
221  	       SUNXI_NFC_BASE + NFC_RCMD_SET);
222  	writel(((page & 0xFFFF) << 16), SUNXI_NFC_BASE + NFC_ADDR_LOW);
223  	writel((page >> 16) & 0xFF, SUNXI_NFC_BASE + NFC_ADDR_HIGH);
224  
225  	return nand_exec_cmd(NFC_SEND_CMD1 | NFC_SEND_CMD2 | NFC_RAW_CMD |
226  			     NFC_SEND_ADDR | NFC_WAIT_FLAG |
227  			     ((conf->addr_cycles - 1) << NFC_ADDR_NUM_OFFSET));
228  }
229  
nand_change_column(u16 column)230  static int nand_change_column(u16 column)
231  {
232  	int ret;
233  
234  	writel((NFC_CMD_RNDOUTSTART << NFC_RANDOM_READ_CMD1_OFFSET) |
235  	       (NFC_CMD_RNDOUT << NFC_RANDOM_READ_CMD0_OFFSET) |
236  	       (NFC_CMD_RNDOUTSTART << NFC_READ_CMD_OFFSET),
237  	       SUNXI_NFC_BASE + NFC_RCMD_SET);
238  	writel(column, SUNXI_NFC_BASE + NFC_ADDR_LOW);
239  
240  	ret = nand_exec_cmd(NFC_SEND_CMD1 | NFC_SEND_CMD2 | NFC_RAW_CMD |
241  			    (1 << NFC_ADDR_NUM_OFFSET) | NFC_SEND_ADDR |
242  			    NFC_CMD_RNDOUT);
243  	if (ret)
244  		return ret;
245  
246  	/* Ensure tCCS has passed before reading data */
247  	udelay(1);
248  
249  	return 0;
250  }
251  
252  static const int ecc_bytes[] = {32, 46, 54, 60, 74, 88, 102, 110, 116};
253  
nand_read_page(const struct nfc_config * conf,u32 offs,void * dest,int len)254  static int nand_read_page(const struct nfc_config *conf, u32 offs,
255  			  void *dest, int len)
256  {
257  	int nsectors = len / conf->ecc_size;
258  	u16 rand_seed = 0;
259  	int oob_chunk_sz = ecc_bytes[conf->ecc_strength];
260  	int page = offs / conf->page_size;
261  	u32 ecc_st;
262  	int i;
263  
264  	if (offs % conf->page_size || len % conf->ecc_size ||
265  	    len > conf->page_size || len < 0)
266  		return -EINVAL;
267  
268  	/* Choose correct seed if randomized */
269  	if (conf->randomize)
270  		rand_seed = random_seed[page % conf->nseeds];
271  
272  	/* Retrieve data from SRAM (PIO) */
273  	for (i = 0; i < nsectors; i++) {
274  		int data_off = i * conf->ecc_size;
275  		int oob_off = conf->page_size + (i * oob_chunk_sz);
276  		u8 *data = dest + data_off;
277  
278  		/* Clear ECC status and restart ECC engine */
279  		writel(0, SUNXI_NFC_BASE + NFC_ECC_ST);
280  		writel((rand_seed << 16) | (conf->ecc_strength << 12) |
281  		       (conf->randomize ? NFC_ECC_RANDOM_EN : 0) |
282  		       (conf->ecc_size == 512 ? NFC_ECC_BLOCK_SIZE : 0) |
283  		       NFC_ECC_EN | NFC_ECC_EXCEPTION,
284  		       SUNXI_NFC_BASE + NFC_ECC_CTL);
285  
286  		/* Move the data in SRAM */
287  		nand_change_column(data_off);
288  		writel(conf->ecc_size, SUNXI_NFC_BASE + NFC_CNT);
289  		nand_exec_cmd(NFC_DATA_TRANS);
290  
291  		/*
292  		 * Let the ECC engine consume the ECC bytes and possibly correct
293  		 * the data.
294  		 */
295  		nand_change_column(oob_off);
296  		nand_exec_cmd(NFC_DATA_TRANS | NFC_ECC_CMD);
297  
298  		/* Get the ECC status */
299  		ecc_st = readl(SUNXI_NFC_BASE + NFC_ECC_ST);
300  
301  		/* ECC error detected. */
302  		if (ecc_st & 0xffff)
303  			return -EIO;
304  
305  		/*
306  		 * Return 1 if the first chunk is empty (needed for
307  		 * configuration detection).
308  		 */
309  		if (!i && (ecc_st & 0x10000))
310  			return 1;
311  
312  		/* Retrieve the data from SRAM */
313  		memcpy_fromio(data, SUNXI_NFC_BASE + NFC_RAM0_BASE,
314  			      conf->ecc_size);
315  
316  		/* Stop the ECC engine */
317  		writel(readl(SUNXI_NFC_BASE + NFC_ECC_CTL) & ~NFC_ECC_EN,
318  		       SUNXI_NFC_BASE + NFC_ECC_CTL);
319  
320  		if (data_off + conf->ecc_size >= len)
321  			break;
322  	}
323  
324  	return 0;
325  }
326  
nand_max_ecc_strength(struct nfc_config * conf)327  static int nand_max_ecc_strength(struct nfc_config *conf)
328  {
329  	int max_oobsize, max_ecc_bytes;
330  	int nsectors = conf->page_size / conf->ecc_size;
331  	int i;
332  
333  	/*
334  	 * ECC strength is limited by the size of the OOB area which is
335  	 * correlated with the page size.
336  	 */
337  	switch (conf->page_size) {
338  	case 2048:
339  		max_oobsize = 64;
340  		break;
341  	case 4096:
342  		max_oobsize = 256;
343  		break;
344  	case 8192:
345  		max_oobsize = 640;
346  		break;
347  	case 16384:
348  		max_oobsize = 1664;
349  		break;
350  	default:
351  		return -EINVAL;
352  	}
353  
354  	max_ecc_bytes = max_oobsize / nsectors;
355  
356  	for (i = 0; i < ARRAY_SIZE(ecc_bytes); i++) {
357  		if (ecc_bytes[i] > max_ecc_bytes)
358  			break;
359  	}
360  
361  	if (!i)
362  		return -EINVAL;
363  
364  	return i - 1;
365  }
366  
nand_detect_ecc_config(struct nfc_config * conf,u32 offs,void * dest)367  static int nand_detect_ecc_config(struct nfc_config *conf, u32 offs,
368  				  void *dest)
369  {
370  	/* NAND with pages > 4k will likely require 1k sector size. */
371  	int min_ecc_size = conf->page_size > 4096 ? 1024 : 512;
372  	int page = offs / conf->page_size;
373  	int ret;
374  
375  	/*
376  	 * In most cases, 1k sectors are preferred over 512b ones, start
377  	 * testing this config first.
378  	 */
379  	for (conf->ecc_size = 1024; conf->ecc_size >= min_ecc_size;
380  	     conf->ecc_size >>= 1) {
381  		int max_ecc_strength = nand_max_ecc_strength(conf);
382  
383  		nand_apply_config(conf);
384  
385  		/*
386  		 * We are starting from the maximum ECC strength because
387  		 * most of the time NAND vendors provide an OOB area that
388  		 * barely meets the ECC requirements.
389  		 */
390  		for (conf->ecc_strength = max_ecc_strength;
391  		     conf->ecc_strength >= 0;
392  		     conf->ecc_strength--) {
393  			conf->randomize = false;
394  			if (nand_change_column(0))
395  				return -EIO;
396  
397  			/*
398  			 * Only read the first sector to speedup detection.
399  			 */
400  			ret = nand_read_page(conf, offs, dest, conf->ecc_size);
401  			if (!ret) {
402  				return 0;
403  			} else if (ret > 0) {
404  				/*
405  				 * If page is empty we can't deduce anything
406  				 * about the ECC config => stop the detection.
407  				 */
408  				return -EINVAL;
409  			}
410  
411  			conf->randomize = true;
412  			conf->nseeds = ARRAY_SIZE(random_seed);
413  			do {
414  				if (nand_change_column(0))
415  					return -EIO;
416  
417  				if (!nand_read_page(conf, offs, dest,
418  						    conf->ecc_size))
419  					return 0;
420  
421  				/*
422  				 * Find the next ->nseeds value that would
423  				 * change the randomizer seed for the page
424  				 * we're trying to read.
425  				 */
426  				while (conf->nseeds >= 16) {
427  					int seed = page % conf->nseeds;
428  
429  					conf->nseeds >>= 1;
430  					if (seed != page % conf->nseeds)
431  						break;
432  				}
433  			} while (conf->nseeds >= 16);
434  		}
435  	}
436  
437  	return -EINVAL;
438  }
439  
nand_detect_config(struct nfc_config * conf,u32 offs,void * dest)440  static int nand_detect_config(struct nfc_config *conf, u32 offs, void *dest)
441  {
442  	if (conf->valid)
443  		return 0;
444  
445  	/*
446  	 * Modern NANDs are more likely than legacy ones, so we start testing
447  	 * with 5 address cycles.
448  	 */
449  	for (conf->addr_cycles = 5;
450  	     conf->addr_cycles >= 4;
451  	     conf->addr_cycles--) {
452  		int max_page_size = conf->addr_cycles == 4 ? 2048 : 16384;
453  
454  		/*
455  		 * Ignoring 1k pages cause I'm not even sure this case exist
456  		 * in the real world.
457  		 */
458  		for (conf->page_size = 2048; conf->page_size <= max_page_size;
459  		     conf->page_size <<= 1) {
460  			if (nand_load_page(conf, offs))
461  				return -1;
462  
463  			if (!nand_detect_ecc_config(conf, offs, dest)) {
464  				conf->valid = true;
465  				return 0;
466  			}
467  		}
468  	}
469  
470  	return -EINVAL;
471  }
472  
nand_read_buffer(struct nfc_config * conf,uint32_t offs,unsigned int size,void * dest)473  static int nand_read_buffer(struct nfc_config *conf, uint32_t offs,
474  			    unsigned int size, void *dest)
475  {
476  	int first_seed = 0, page, ret;
477  
478  	size = ALIGN(size, conf->page_size);
479  	page = offs / conf->page_size;
480  	if (conf->randomize)
481  		first_seed = page % conf->nseeds;
482  
483  	for (; size; size -= conf->page_size) {
484  		if (nand_load_page(conf, offs))
485  			return -1;
486  
487  		ret = nand_read_page(conf, offs, dest, conf->page_size);
488  		/*
489  		 * The ->nseeds value should be equal to the number of pages
490  		 * in an eraseblock. Since we don't know this information in
491  		 * advance we might have picked a wrong value.
492  		 */
493  		if (ret < 0 && conf->randomize) {
494  			int cur_seed = page % conf->nseeds;
495  
496  			/*
497  			 * We already tried all the seed values => we are
498  			 * facing a real corruption.
499  			 */
500  			if (cur_seed < first_seed)
501  				return -EIO;
502  
503  			/* Try to adjust ->nseeds and read the page again... */
504  			conf->nseeds = cur_seed;
505  
506  			if (nand_change_column(0))
507  				return -EIO;
508  
509  			/* ... it still fails => it's a real corruption. */
510  			if (nand_read_page(conf, offs, dest, conf->page_size))
511  				return -EIO;
512  		} else if (ret && conf->randomize) {
513  			memset(dest, 0xff, conf->page_size);
514  		}
515  
516  		page++;
517  		offs += conf->page_size;
518  		dest += conf->page_size;
519  	}
520  
521  	return 0;
522  }
523  
nand_spl_load_image(uint32_t offs,unsigned int size,void * dest)524  int nand_spl_load_image(uint32_t offs, unsigned int size, void *dest)
525  {
526  	static struct nfc_config conf = { };
527  	int ret;
528  
529  	ret = nand_detect_config(&conf, offs, dest);
530  	if (ret)
531  		return ret;
532  
533  	return nand_read_buffer(&conf, offs, size, dest);
534  }
535  
nand_deselect(void)536  void nand_deselect(void)
537  {
538  	struct sunxi_ccm_reg *const ccm =
539  		(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
540  
541  	clrbits_le32(&ccm->ahb_gate0, (CLK_GATE_OPEN << AHB_GATE_OFFSET_NAND0));
542  #ifdef CONFIG_MACH_SUN9I
543  	clrbits_le32(&ccm->ahb_gate1, (1 << AHB_GATE_OFFSET_DMA));
544  #else
545  	clrbits_le32(&ccm->ahb_gate0, (1 << AHB_GATE_OFFSET_DMA));
546  #endif
547  	clrbits_le32(&ccm->nand0_clk_cfg, CCM_NAND_CTRL_ENABLE | AHB_DIV_1);
548  }
549