1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2012-2014 Daniel Schwierzeck, daniel.schwierzeck@gmail.com
4 */
5
6 #include <common.h>
7 #include <flash.h>
8 #include <malloc.h>
9 #include <linux/errno.h>
10 #include <linux/mtd/mtd.h>
11 #include <spi_flash.h>
12
13 static struct mtd_info sf_mtd_info;
14 static bool sf_mtd_registered;
15 static char sf_mtd_name[8];
16
spi_flash_mtd_erase(struct mtd_info * mtd,struct erase_info * instr)17 static int spi_flash_mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
18 {
19 struct spi_flash *flash = mtd->priv;
20 int err;
21
22 if (!flash)
23 return -ENODEV;
24
25 instr->state = MTD_ERASING;
26
27 err = spi_flash_erase(flash, instr->addr, instr->len);
28 if (err) {
29 instr->state = MTD_ERASE_FAILED;
30 instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
31 return -EIO;
32 }
33
34 instr->state = MTD_ERASE_DONE;
35 mtd_erase_callback(instr);
36
37 return 0;
38 }
39
spi_flash_mtd_read(struct mtd_info * mtd,loff_t from,size_t len,size_t * retlen,u_char * buf)40 static int spi_flash_mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
41 size_t *retlen, u_char *buf)
42 {
43 struct spi_flash *flash = mtd->priv;
44 int err;
45
46 if (!flash)
47 return -ENODEV;
48
49 err = spi_flash_read(flash, from, len, buf);
50 if (!err)
51 *retlen = len;
52
53 return err;
54 }
55
spi_flash_mtd_write(struct mtd_info * mtd,loff_t to,size_t len,size_t * retlen,const u_char * buf)56 static int spi_flash_mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
57 size_t *retlen, const u_char *buf)
58 {
59 struct spi_flash *flash = mtd->priv;
60 int err;
61
62 if (!flash)
63 return -ENODEV;
64
65 err = spi_flash_write(flash, to, len, buf);
66 if (!err)
67 *retlen = len;
68
69 return err;
70 }
71
spi_flash_mtd_sync(struct mtd_info * mtd)72 static void spi_flash_mtd_sync(struct mtd_info *mtd)
73 {
74 }
75
spi_flash_mtd_number(void)76 static int spi_flash_mtd_number(void)
77 {
78 #ifdef CONFIG_SYS_MAX_FLASH_BANKS
79 return CONFIG_SYS_MAX_FLASH_BANKS;
80 #else
81 return 0;
82 #endif
83 }
84
spi_flash_mtd_register(struct spi_flash * flash)85 int spi_flash_mtd_register(struct spi_flash *flash)
86 {
87 int ret;
88
89 if (sf_mtd_registered) {
90 ret = del_mtd_device(&sf_mtd_info);
91 if (ret)
92 return ret;
93
94 sf_mtd_registered = false;
95 }
96
97 sf_mtd_registered = false;
98 memset(&sf_mtd_info, 0, sizeof(sf_mtd_info));
99 sprintf(sf_mtd_name, "nor%d", spi_flash_mtd_number());
100
101 sf_mtd_info.name = sf_mtd_name;
102 sf_mtd_info.type = MTD_NORFLASH;
103 sf_mtd_info.flags = MTD_CAP_NORFLASH;
104 sf_mtd_info.writesize = 1;
105 sf_mtd_info.writebufsize = flash->page_size;
106
107 sf_mtd_info._erase = spi_flash_mtd_erase;
108 sf_mtd_info._read = spi_flash_mtd_read;
109 sf_mtd_info._write = spi_flash_mtd_write;
110 sf_mtd_info._sync = spi_flash_mtd_sync;
111
112 sf_mtd_info.size = flash->size;
113 sf_mtd_info.priv = flash;
114
115 /* Only uniform flash devices for now */
116 sf_mtd_info.numeraseregions = 0;
117 sf_mtd_info.erasesize = flash->sector_size;
118
119 ret = add_mtd_device(&sf_mtd_info);
120 if (!ret)
121 sf_mtd_registered = true;
122
123 return ret;
124 }
125
spi_flash_mtd_unregister(void)126 void spi_flash_mtd_unregister(void)
127 {
128 int ret;
129
130 if (!sf_mtd_registered)
131 return;
132
133 ret = del_mtd_device(&sf_mtd_info);
134 if (!ret) {
135 sf_mtd_registered = false;
136 return;
137 }
138
139 /*
140 * Setting mtd->priv to NULL is the best we can do. Thanks to that,
141 * the MTD layer can still call mtd hooks without risking a
142 * use-after-free bug. Still, things should be fixed to prevent the
143 * spi_flash object from being destroyed when del_mtd_device() fails.
144 */
145 sf_mtd_info.priv = NULL;
146 printf("Failed to unregister MTD %s and the spi_flash object is going away: you're in deep trouble!",
147 sf_mtd_info.name);
148 }
149