1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2012
4  * Konstantin Kozhevnikov, Cogent Embedded
5  *
6  * based on nand_spl_simple code
7  *
8  * (C) Copyright 2006-2008
9  * Stefan Roese, DENX Software Engineering, sr@denx.de.
10  */
11 
12 #include <common.h>
13 #include <nand.h>
14 #include <asm/io.h>
15 #include <linux/mtd/nand_ecc.h>
16 
17 static int nand_ecc_pos[] = CONFIG_SYS_NAND_ECCPOS;
18 static struct mtd_info *mtd;
19 static struct nand_chip nand_chip;
20 
21 #define ECCSTEPS	(CONFIG_SYS_NAND_PAGE_SIZE / \
22 					CONFIG_SYS_NAND_ECCSIZE)
23 #define ECCTOTAL	(ECCSTEPS * CONFIG_SYS_NAND_ECCBYTES)
24 
25 
26 /*
27  * NAND command for large page NAND devices (2k)
28  */
29 static int nand_command(int block, int page, uint32_t offs,
30 	u8 cmd)
31 {
32 	struct nand_chip *this = mtd_to_nand(mtd);
33 	int page_addr = page + block * CONFIG_SYS_NAND_PAGE_COUNT;
34 	void (*hwctrl)(struct mtd_info *mtd, int cmd,
35 			unsigned int ctrl) = this->cmd_ctrl;
36 
37 	while (!this->dev_ready(mtd))
38 		;
39 
40 	/* Emulate NAND_CMD_READOOB */
41 	if (cmd == NAND_CMD_READOOB) {
42 		offs += CONFIG_SYS_NAND_PAGE_SIZE;
43 		cmd = NAND_CMD_READ0;
44 	}
45 
46 	/* Begin command latch cycle */
47 	hwctrl(mtd, cmd, NAND_CTRL_CLE | NAND_CTRL_CHANGE);
48 
49 	if (cmd == NAND_CMD_RESET) {
50 		hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
51 
52 		/*
53 		 * Apply this short delay always to ensure that we do wait
54 		 * tWB in any case on any machine.
55 		 */
56 		ndelay(150);
57 
58 		while (!this->dev_ready(mtd))
59 			;
60 		return 0;
61 	}
62 
63 	/* Shift the offset from byte addressing to word addressing. */
64 	if ((this->options & NAND_BUSWIDTH_16) && !nand_opcode_8bits(cmd))
65 		offs >>= 1;
66 
67 	/* Set ALE and clear CLE to start address cycle */
68 	/* Column address */
69 	hwctrl(mtd, offs & 0xff,
70 		       NAND_CTRL_ALE | NAND_CTRL_CHANGE); /* A[7:0] */
71 	hwctrl(mtd, (offs >> 8) & 0xff, NAND_CTRL_ALE); /* A[11:9] */
72 	/* Row address */
73 	if (cmd != NAND_CMD_RNDOUT) {
74 		hwctrl(mtd, (page_addr & 0xff),
75 		       NAND_CTRL_ALE); /* A[19:12] */
76 		hwctrl(mtd, ((page_addr >> 8) & 0xff),
77 		       NAND_CTRL_ALE); /* A[27:20] */
78 #ifdef CONFIG_SYS_NAND_5_ADDR_CYCLE
79 		/* One more address cycle for devices > 128MiB */
80 		hwctrl(mtd, (page_addr >> 16) & 0x0f,
81 		       NAND_CTRL_ALE); /* A[31:28] */
82 #endif
83 	}
84 
85 	hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
86 
87 
88 	/*
89 	 * Program and erase have their own busy handlers status, sequential
90 	 * in and status need no delay.
91 	 */
92 	switch (cmd) {
93 	case NAND_CMD_CACHEDPROG:
94 	case NAND_CMD_PAGEPROG:
95 	case NAND_CMD_ERASE1:
96 	case NAND_CMD_ERASE2:
97 	case NAND_CMD_SEQIN:
98 	case NAND_CMD_RNDIN:
99 	case NAND_CMD_STATUS:
100 		return 0;
101 
102 	case NAND_CMD_RNDOUT:
103 		/* No ready / busy check necessary */
104 		hwctrl(mtd, NAND_CMD_RNDOUTSTART, NAND_CTRL_CLE |
105 		       NAND_CTRL_CHANGE);
106 		hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
107 		return 0;
108 
109 	case NAND_CMD_READ0:
110 		/* Latch in address */
111 		hwctrl(mtd, NAND_CMD_READSTART,
112 		       NAND_CTRL_CLE | NAND_CTRL_CHANGE);
113 		hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
114 	}
115 
116 	/*
117 	 * Apply this short delay always to ensure that we do wait tWB in
118 	 * any case on any machine.
119 	 */
120 	ndelay(150);
121 
122 	while (!this->dev_ready(mtd))
123 		;
124 
125 	return 0;
126 }
127 
128 static int nand_is_bad_block(int block)
129 {
130 	struct nand_chip *this = mtd_to_nand(mtd);
131 
132 	nand_command(block, 0, CONFIG_SYS_NAND_BAD_BLOCK_POS,
133 		NAND_CMD_READOOB);
134 
135 	/*
136 	 * Read one byte (or two if it's a 16 bit chip).
137 	 */
138 	if (this->options & NAND_BUSWIDTH_16) {
139 		if (readw(this->IO_ADDR_R) != 0xffff)
140 			return 1;
141 	} else {
142 		if (readb(this->IO_ADDR_R) != 0xff)
143 			return 1;
144 	}
145 
146 	return 0;
147 }
148 
149 static int nand_read_page(int block, int page, void *dst)
150 {
151 	struct nand_chip *this = mtd_to_nand(mtd);
152 	u_char ecc_calc[ECCTOTAL];
153 	u_char ecc_code[ECCTOTAL];
154 	u_char oob_data[CONFIG_SYS_NAND_OOBSIZE];
155 	int i;
156 	int eccsize = CONFIG_SYS_NAND_ECCSIZE;
157 	int eccbytes = CONFIG_SYS_NAND_ECCBYTES;
158 	int eccsteps = ECCSTEPS;
159 	uint8_t *p = dst;
160 	uint32_t data_pos = 0;
161 	uint8_t *oob = &oob_data[0] + nand_ecc_pos[0];
162 	uint32_t oob_pos = eccsize * eccsteps + nand_ecc_pos[0];
163 
164 	nand_command(block, page, 0, NAND_CMD_READ0);
165 
166 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
167 		this->ecc.hwctl(mtd, NAND_ECC_READ);
168 		nand_command(block, page, data_pos, NAND_CMD_RNDOUT);
169 
170 		this->read_buf(mtd, p, eccsize);
171 
172 		nand_command(block, page, oob_pos, NAND_CMD_RNDOUT);
173 
174 		this->read_buf(mtd, oob, eccbytes);
175 		this->ecc.calculate(mtd, p, &ecc_calc[i]);
176 
177 		data_pos += eccsize;
178 		oob_pos += eccbytes;
179 		oob += eccbytes;
180 	}
181 
182 	/* Pick the ECC bytes out of the oob data */
183 	for (i = 0; i < ECCTOTAL; i++)
184 		ecc_code[i] = oob_data[nand_ecc_pos[i]];
185 
186 	eccsteps = ECCSTEPS;
187 	p = dst;
188 
189 	for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
190 		/* No chance to do something with the possible error message
191 		 * from correct_data(). We just hope that all possible errors
192 		 * are corrected by this routine.
193 		 */
194 		this->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
195 	}
196 
197 	return 0;
198 }
199 
200 /* nand_init() - initialize data to make nand usable by SPL */
201 void nand_init(void)
202 {
203 	/*
204 	 * Init board specific nand support
205 	 */
206 	mtd = nand_to_mtd(&nand_chip);
207 	nand_chip.IO_ADDR_R = nand_chip.IO_ADDR_W =
208 		(void  __iomem *)CONFIG_SYS_NAND_BASE;
209 	board_nand_init(&nand_chip);
210 
211 	if (nand_chip.select_chip)
212 		nand_chip.select_chip(mtd, 0);
213 
214 	/* NAND chip may require reset after power-on */
215 	nand_command(0, 0, 0, NAND_CMD_RESET);
216 }
217 
218 /* Unselect after operation */
219 void nand_deselect(void)
220 {
221 	if (nand_chip.select_chip)
222 		nand_chip.select_chip(mtd, -1);
223 }
224 
225 #include "nand_spl_loaders.c"
226