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11#include <linux/slab.h>
12#include <linux/module.h>
13#include <linux/mtd/mtd.h>
14#include <linux/mtd/rawnand.h>
15#include <linux/mtd/partitions.h>
16#include <linux/of_address.h>
17#include <linux/of_platform.h>
18#include <linux/io.h>
19
20#define FPGA_NAND_CMD_MASK (0x7 << 28)
21#define FPGA_NAND_CMD_COMMAND (0x0 << 28)
22#define FPGA_NAND_CMD_ADDR (0x1 << 28)
23#define FPGA_NAND_CMD_READ (0x2 << 28)
24#define FPGA_NAND_CMD_WRITE (0x3 << 28)
25#define FPGA_NAND_BUSY (0x1 << 15)
26#define FPGA_NAND_ENABLE (0x1 << 31)
27#define FPGA_NAND_DATA_SHIFT 16
28
29struct socrates_nand_host {
30 struct nand_chip nand_chip;
31 void __iomem *io_base;
32 struct device *dev;
33};
34
35
36
37
38
39
40
41static void socrates_nand_write_buf(struct mtd_info *mtd,
42 const uint8_t *buf, int len)
43{
44 int i;
45 struct nand_chip *this = mtd_to_nand(mtd);
46 struct socrates_nand_host *host = nand_get_controller_data(this);
47
48 for (i = 0; i < len; i++) {
49 out_be32(host->io_base, FPGA_NAND_ENABLE |
50 FPGA_NAND_CMD_WRITE |
51 (buf[i] << FPGA_NAND_DATA_SHIFT));
52 }
53}
54
55
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58
59
60
61static void socrates_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
62{
63 int i;
64 struct nand_chip *this = mtd_to_nand(mtd);
65 struct socrates_nand_host *host = nand_get_controller_data(this);
66 uint32_t val;
67
68 val = FPGA_NAND_ENABLE | FPGA_NAND_CMD_READ;
69
70 out_be32(host->io_base, val);
71 for (i = 0; i < len; i++) {
72 buf[i] = (in_be32(host->io_base) >>
73 FPGA_NAND_DATA_SHIFT) & 0xff;
74 }
75}
76
77
78
79
80
81static uint8_t socrates_nand_read_byte(struct mtd_info *mtd)
82{
83 uint8_t byte;
84 socrates_nand_read_buf(mtd, &byte, sizeof(byte));
85 return byte;
86}
87
88
89
90
91
92static uint16_t socrates_nand_read_word(struct mtd_info *mtd)
93{
94 uint16_t word;
95 socrates_nand_read_buf(mtd, (uint8_t *)&word, sizeof(word));
96 return word;
97}
98
99
100
101
102static void socrates_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
103 unsigned int ctrl)
104{
105 struct nand_chip *nand_chip = mtd_to_nand(mtd);
106 struct socrates_nand_host *host = nand_get_controller_data(nand_chip);
107 uint32_t val;
108
109 if (cmd == NAND_CMD_NONE)
110 return;
111
112 if (ctrl & NAND_CLE)
113 val = FPGA_NAND_CMD_COMMAND;
114 else
115 val = FPGA_NAND_CMD_ADDR;
116
117 if (ctrl & NAND_NCE)
118 val |= FPGA_NAND_ENABLE;
119
120 val |= (cmd & 0xff) << FPGA_NAND_DATA_SHIFT;
121
122 out_be32(host->io_base, val);
123}
124
125
126
127
128static int socrates_nand_device_ready(struct mtd_info *mtd)
129{
130 struct nand_chip *nand_chip = mtd_to_nand(mtd);
131 struct socrates_nand_host *host = nand_get_controller_data(nand_chip);
132
133 if (in_be32(host->io_base) & FPGA_NAND_BUSY)
134 return 0;
135 return 1;
136}
137
138
139
140
141static int socrates_nand_probe(struct platform_device *ofdev)
142{
143 struct socrates_nand_host *host;
144 struct mtd_info *mtd;
145 struct nand_chip *nand_chip;
146 int res;
147
148
149 host = devm_kzalloc(&ofdev->dev, sizeof(*host), GFP_KERNEL);
150 if (!host)
151 return -ENOMEM;
152
153 host->io_base = of_iomap(ofdev->dev.of_node, 0);
154 if (host->io_base == NULL) {
155 dev_err(&ofdev->dev, "ioremap failed\n");
156 return -EIO;
157 }
158
159 nand_chip = &host->nand_chip;
160 mtd = nand_to_mtd(nand_chip);
161 host->dev = &ofdev->dev;
162
163
164 nand_set_controller_data(nand_chip, host);
165 nand_set_flash_node(nand_chip, ofdev->dev.of_node);
166 mtd->name = "socrates_nand";
167 mtd->dev.parent = &ofdev->dev;
168
169
170 nand_chip->IO_ADDR_R = (void *)0xdeadbeef;
171 nand_chip->IO_ADDR_W = (void *)0xdeadbeef;
172
173 nand_chip->cmd_ctrl = socrates_nand_cmd_ctrl;
174 nand_chip->read_byte = socrates_nand_read_byte;
175 nand_chip->read_word = socrates_nand_read_word;
176 nand_chip->write_buf = socrates_nand_write_buf;
177 nand_chip->read_buf = socrates_nand_read_buf;
178 nand_chip->dev_ready = socrates_nand_device_ready;
179
180 nand_chip->ecc.mode = NAND_ECC_SOFT;
181 nand_chip->ecc.algo = NAND_ECC_HAMMING;
182
183
184 nand_chip->chip_delay = 20;
185
186 dev_set_drvdata(&ofdev->dev, host);
187
188 res = nand_scan(mtd, 1);
189 if (res)
190 goto out;
191
192 res = mtd_device_register(mtd, NULL, 0);
193 if (!res)
194 return res;
195
196 nand_release(mtd);
197
198out:
199 iounmap(host->io_base);
200 return res;
201}
202
203
204
205
206static int socrates_nand_remove(struct platform_device *ofdev)
207{
208 struct socrates_nand_host *host = dev_get_drvdata(&ofdev->dev);
209 struct mtd_info *mtd = nand_to_mtd(&host->nand_chip);
210
211 nand_release(mtd);
212
213 iounmap(host->io_base);
214
215 return 0;
216}
217
218static const struct of_device_id socrates_nand_match[] =
219{
220 {
221 .compatible = "abb,socrates-nand",
222 },
223 {},
224};
225
226MODULE_DEVICE_TABLE(of, socrates_nand_match);
227
228static struct platform_driver socrates_nand_driver = {
229 .driver = {
230 .name = "socrates_nand",
231 .of_match_table = socrates_nand_match,
232 },
233 .probe = socrates_nand_probe,
234 .remove = socrates_nand_remove,
235};
236
237module_platform_driver(socrates_nand_driver);
238
239MODULE_LICENSE("GPL");
240MODULE_AUTHOR("Ilya Yanok");
241MODULE_DESCRIPTION("NAND driver for Socrates board");
242