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/delay.h>
16 #include <linux/mtd/nand_ecc.h>
17 #include <linux/mtd/rawnand.h>
18 
19 static int nand_ecc_pos[] = CONFIG_SYS_NAND_ECCPOS;
20 static struct mtd_info *mtd;
21 static struct nand_chip nand_chip;
22 
23 #define ECCSTEPS	(CONFIG_SYS_NAND_PAGE_SIZE / \
24 					CONFIG_SYS_NAND_ECCSIZE)
25 #define ECCTOTAL	(ECCSTEPS * CONFIG_SYS_NAND_ECCBYTES)
26 
27 
28 /*
29  * NAND command for large page NAND devices (2k)
30  */
nand_command(int block,int page,uint32_t offs,u8 cmd)31 static int nand_command(int block, int page, uint32_t offs,
32 	u8 cmd)
33 {
34 	struct nand_chip *this = mtd_to_nand(mtd);
35 	int page_addr = page + block * CONFIG_SYS_NAND_PAGE_COUNT;
36 	void (*hwctrl)(struct mtd_info *mtd, int cmd,
37 			unsigned int ctrl) = this->cmd_ctrl;
38 
39 	while (!this->dev_ready(mtd))
40 		;
41 
42 	/* Emulate NAND_CMD_READOOB */
43 	if (cmd == NAND_CMD_READOOB) {
44 		offs += CONFIG_SYS_NAND_PAGE_SIZE;
45 		cmd = NAND_CMD_READ0;
46 	}
47 
48 	/* Begin command latch cycle */
49 	hwctrl(mtd, cmd, NAND_CTRL_CLE | NAND_CTRL_CHANGE);
50 
51 	if (cmd == NAND_CMD_RESET) {
52 		hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
53 
54 		/*
55 		 * Apply this short delay always to ensure that we do wait
56 		 * tWB in any case on any machine.
57 		 */
58 		ndelay(150);
59 
60 		while (!this->dev_ready(mtd))
61 			;
62 		return 0;
63 	}
64 
65 	/* Shift the offset from byte addressing to word addressing. */
66 	if ((this->options & NAND_BUSWIDTH_16) && !nand_opcode_8bits(cmd))
67 		offs >>= 1;
68 
69 	/* Set ALE and clear CLE to start address cycle */
70 	/* Column address */
71 	hwctrl(mtd, offs & 0xff,
72 		       NAND_CTRL_ALE | NAND_CTRL_CHANGE); /* A[7:0] */
73 	hwctrl(mtd, (offs >> 8) & 0xff, NAND_CTRL_ALE); /* A[11:9] */
74 	/* Row address */
75 	if (cmd != NAND_CMD_RNDOUT) {
76 		hwctrl(mtd, (page_addr & 0xff),
77 		       NAND_CTRL_ALE); /* A[19:12] */
78 		hwctrl(mtd, ((page_addr >> 8) & 0xff),
79 		       NAND_CTRL_ALE); /* A[27:20] */
80 #ifdef CONFIG_SYS_NAND_5_ADDR_CYCLE
81 		/* One more address cycle for devices > 128MiB */
82 		hwctrl(mtd, (page_addr >> 16) & 0x0f,
83 		       NAND_CTRL_ALE); /* A[31:28] */
84 #endif
85 	}
86 
87 	hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
88 
89 
90 	/*
91 	 * Program and erase have their own busy handlers status, sequential
92 	 * in and status need no delay.
93 	 */
94 	switch (cmd) {
95 	case NAND_CMD_CACHEDPROG:
96 	case NAND_CMD_PAGEPROG:
97 	case NAND_CMD_ERASE1:
98 	case NAND_CMD_ERASE2:
99 	case NAND_CMD_SEQIN:
100 	case NAND_CMD_RNDIN:
101 	case NAND_CMD_STATUS:
102 		return 0;
103 
104 	case NAND_CMD_RNDOUT:
105 		/* No ready / busy check necessary */
106 		hwctrl(mtd, NAND_CMD_RNDOUTSTART, NAND_CTRL_CLE |
107 		       NAND_CTRL_CHANGE);
108 		hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
109 		return 0;
110 
111 	case NAND_CMD_READ0:
112 		/* Latch in address */
113 		hwctrl(mtd, NAND_CMD_READSTART,
114 		       NAND_CTRL_CLE | NAND_CTRL_CHANGE);
115 		hwctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
116 	}
117 
118 	/*
119 	 * Apply this short delay always to ensure that we do wait tWB in
120 	 * any case on any machine.
121 	 */
122 	ndelay(150);
123 
124 	while (!this->dev_ready(mtd))
125 		;
126 
127 	return 0;
128 }
129 
nand_is_bad_block(int block)130 static int nand_is_bad_block(int block)
131 {
132 	struct nand_chip *this = mtd_to_nand(mtd);
133 
134 	nand_command(block, 0, CONFIG_SYS_NAND_BAD_BLOCK_POS,
135 		NAND_CMD_READOOB);
136 
137 	/*
138 	 * Read one byte (or two if it's a 16 bit chip).
139 	 */
140 	if (this->options & NAND_BUSWIDTH_16) {
141 		if (readw(this->IO_ADDR_R) != 0xffff)
142 			return 1;
143 	} else {
144 		if (readb(this->IO_ADDR_R) != 0xff)
145 			return 1;
146 	}
147 
148 	return 0;
149 }
150 
nand_read_page(int block,int page,void * dst)151 static int nand_read_page(int block, int page, void *dst)
152 {
153 	struct nand_chip *this = mtd_to_nand(mtd);
154 	u_char ecc_calc[ECCTOTAL];
155 	u_char ecc_code[ECCTOTAL];
156 	u_char oob_data[CONFIG_SYS_NAND_OOBSIZE];
157 	int i;
158 	int eccsize = CONFIG_SYS_NAND_ECCSIZE;
159 	int eccbytes = CONFIG_SYS_NAND_ECCBYTES;
160 	int eccsteps = ECCSTEPS;
161 	uint8_t *p = dst;
162 	uint32_t data_pos = 0;
163 	uint8_t *oob = &oob_data[0] + nand_ecc_pos[0];
164 	uint32_t oob_pos = eccsize * eccsteps + nand_ecc_pos[0];
165 
166 	nand_command(block, page, 0, NAND_CMD_READ0);
167 
168 	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
169 		this->ecc.hwctl(mtd, NAND_ECC_READ);
170 		nand_command(block, page, data_pos, NAND_CMD_RNDOUT);
171 
172 		this->read_buf(mtd, p, eccsize);
173 
174 		nand_command(block, page, oob_pos, NAND_CMD_RNDOUT);
175 
176 		this->read_buf(mtd, oob, eccbytes);
177 		this->ecc.calculate(mtd, p, &ecc_calc[i]);
178 
179 		data_pos += eccsize;
180 		oob_pos += eccbytes;
181 		oob += eccbytes;
182 	}
183 
184 	/* Pick the ECC bytes out of the oob data */
185 	for (i = 0; i < ECCTOTAL; i++)
186 		ecc_code[i] = oob_data[nand_ecc_pos[i]];
187 
188 	eccsteps = ECCSTEPS;
189 	p = dst;
190 
191 	for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
192 		/* No chance to do something with the possible error message
193 		 * from correct_data(). We just hope that all possible errors
194 		 * are corrected by this routine.
195 		 */
196 		this->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
197 	}
198 
199 	return 0;
200 }
201 
202 /* nand_init() - initialize data to make nand usable by SPL */
nand_init(void)203 void nand_init(void)
204 {
205 	/*
206 	 * Init board specific nand support
207 	 */
208 	mtd = nand_to_mtd(&nand_chip);
209 	nand_chip.IO_ADDR_R = nand_chip.IO_ADDR_W =
210 		(void  __iomem *)CONFIG_SYS_NAND_BASE;
211 	board_nand_init(&nand_chip);
212 
213 	if (nand_chip.select_chip)
214 		nand_chip.select_chip(mtd, 0);
215 
216 	/* NAND chip may require reset after power-on */
217 	nand_command(0, 0, 0, NAND_CMD_RESET);
218 }
219 
220 /* Unselect after operation */
nand_deselect(void)221 void nand_deselect(void)
222 {
223 	if (nand_chip.select_chip)
224 		nand_chip.select_chip(mtd, -1);
225 }
226 
227 #include "nand_spl_loaders.c"
228