2 * R/O (V)FAT 12/16/32 filesystem implementation by Marcus Sundberg
4 * 2002-07-28 - rjones@nexus-tech.net - ported to ppcboot v1.1.6
5 * 2003-03-10 - kharris@nexus-tech.net - ported to u-boot
7 * SPDX-License-Identifier: GPL-2.0+
13 #include <asm/byteorder.h>
15 #define CONFIG_SUPPORT_VFAT
16 /* Maximum Long File Name length supported here is 128 UTF-16 code units */
17 #define VFAT_MAXLEN_BYTES 256 /* Maximum LFN buffer in bytes */
18 #define VFAT_MAXSEQ 9 /* Up to 9 of 13 2-byte UTF-16 entries */
19 #define PREFETCH_BLOCKS 2
21 #define MAX_CLUSTSIZE 65536
22 #define DIRENTSPERBLOCK (mydata->sect_size / sizeof(dir_entry))
23 #define DIRENTSPERCLUST ((mydata->clust_size * mydata->sect_size) / \
26 #define FATBUFBLOCKS 6
27 #define FATBUFSIZE (mydata->sect_size * FATBUFBLOCKS)
28 #define FAT12BUFSIZE ((FATBUFSIZE*2)/3)
29 #define FAT16BUFSIZE (FATBUFSIZE/2)
30 #define FAT32BUFSIZE (FATBUFSIZE/4)
33 /* Filesystem identifiers */
34 #define FAT12_SIGN "FAT12 "
35 #define FAT16_SIGN "FAT16 "
36 #define FAT32_SIGN "FAT32 "
47 #define ATTR_VFAT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME)
49 #define DELETED_FLAG ((char)0xe5) /* Marks deleted files when in name[0] */
50 #define aRING 0x05 /* Used as special character in name[0] */
53 * Indicates that the entry is the last long entry in a set of long
56 #define LAST_LONG_ENTRY_MASK 0x40
58 /* Flags telling whether we should read a file or list a directory */
64 #define ISDIRDELIM(c) ((c) == '/' || (c) == '\\')
66 #define FSTYPE_NONE (-1)
68 #if defined(__linux__) && defined(__KERNEL__)
69 #define FAT2CPU16 le16_to_cpu
70 #define FAT2CPU32 le32_to_cpu
73 #define FAT2CPU16(x) (x)
74 #define FAT2CPU32(x) (x)
76 #define FAT2CPU16(x) ((((x) & 0x00ff) << 8) | (((x) & 0xff00) >> 8))
77 #define FAT2CPU32(x) ((((x) & 0x000000ff) << 24) | \
78 (((x) & 0x0000ff00) << 8) | \
79 (((x) & 0x00ff0000) >> 8) | \
80 (((x) & 0xff000000) >> 24))
84 #define START(dent) (FAT2CPU16((dent)->start) \
85 + (mydata->fatsize != 32 ? 0 : \
86 (FAT2CPU16((dent)->starthi) << 16)))
87 #define CHECK_CLUST(x, fatsize) ((x) <= 1 || \
88 (x) >= ((fatsize) != 32 ? 0xfff0 : 0xffffff0))
90 typedef struct boot_sector {
91 __u8 ignored[3]; /* Bootstrap code */
92 char system_id[8]; /* Name of fs */
93 __u8 sector_size[2]; /* Bytes/sector */
94 __u8 cluster_size; /* Sectors/cluster */
95 __u16 reserved; /* Number of reserved sectors */
96 __u8 fats; /* Number of FATs */
97 __u8 dir_entries[2]; /* Number of root directory entries */
98 __u8 sectors[2]; /* Number of sectors */
99 __u8 media; /* Media code */
100 __u16 fat_length; /* Sectors/FAT */
101 __u16 secs_track; /* Sectors/track */
102 __u16 heads; /* Number of heads */
103 __u32 hidden; /* Number of hidden sectors */
104 __u32 total_sect; /* Number of sectors (if sectors == 0) */
107 __u32 fat32_length; /* Sectors/FAT */
108 __u16 flags; /* Bit 8: fat mirroring, low 4: active fat */
109 __u8 version[2]; /* Filesystem version */
110 __u32 root_cluster; /* First cluster in root directory */
111 __u16 info_sector; /* Filesystem info sector */
112 __u16 backup_boot; /* Backup boot sector */
113 __u16 reserved2[6]; /* Unused */
116 typedef struct volume_info
118 __u8 drive_number; /* BIOS drive number */
119 __u8 reserved; /* Unused */
120 __u8 ext_boot_sign; /* 0x29 if fields below exist (DOS 3.3+) */
121 __u8 volume_id[4]; /* Volume ID number */
122 char volume_label[11]; /* Volume label */
123 char fs_type[8]; /* Typically FAT12, FAT16, or FAT32 */
124 /* Boot code comes next, all but 2 bytes to fill up sector */
125 /* Boot sign comes last, 2 bytes */
128 typedef struct dir_entry {
129 char name[8],ext[3]; /* Name and extension */
130 __u8 attr; /* Attribute bits */
131 __u8 lcase; /* Case for base and extension */
132 __u8 ctime_ms; /* Creation time, milliseconds */
133 __u16 ctime; /* Creation time */
134 __u16 cdate; /* Creation date */
135 __u16 adate; /* Last access date */
136 __u16 starthi; /* High 16 bits of cluster in FAT32 */
137 __u16 time,date,start;/* Time, date and first cluster */
138 __u32 size; /* File size in bytes */
141 typedef struct dir_slot {
142 __u8 id; /* Sequence number for slot */
143 __u8 name0_4[10]; /* First 5 characters in name */
144 __u8 attr; /* Attribute byte */
145 __u8 reserved; /* Unused */
146 __u8 alias_checksum;/* Checksum for 8.3 alias */
147 __u8 name5_10[12]; /* 6 more characters in name */
148 __u16 start; /* Unused */
149 __u8 name11_12[4]; /* Last 2 characters in name */
153 * Private filesystem parameters
155 * Note: FAT buffer has to be 32 bit aligned
156 * (see FAT32 accesses)
159 __u8 *fatbuf; /* Current FAT buffer */
160 int fatsize; /* Size of FAT in bits */
161 __u32 fatlength; /* Length of FAT in sectors */
162 __u16 fat_sect; /* Starting sector of the FAT */
163 __u32 rootdir_sect; /* Start sector of root directory */
164 __u16 sect_size; /* Size of sectors in bytes */
165 __u16 clust_size; /* Size of clusters in sectors */
166 int data_begin; /* The sector of the first cluster, can be negative */
167 int fatbufnum; /* Used by get_fatent, init to -1 */
170 typedef int (file_detectfs_func)(void);
171 typedef int (file_ls_func)(const char *dir);
172 typedef long (file_read_func)(const char *filename, void *buffer,
173 unsigned long maxsize);
176 file_detectfs_func *detect;
178 file_read_func *read;
183 file_detectfs_func file_fat_detectfs;
184 file_ls_func file_fat_ls;
185 file_read_func file_fat_read;
187 /* Currently this doesn't check if the dir exists or is valid... */
188 int file_cd(const char *path);
189 int file_fat_detectfs(void);
190 int file_fat_ls(const char *dir);
191 long file_fat_read_at(const char *filename, unsigned long pos, void *buffer,
192 unsigned long maxsize);
193 long file_fat_read(const char *filename, void *buffer, unsigned long maxsize);
194 const char *file_getfsname(int idx);
195 int fat_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info);
196 int fat_register_device(block_dev_desc_t *dev_desc, int part_no);
198 int file_fat_write(const char *filename, void *buffer, unsigned long maxsize);
199 int fat_read_file(const char *filename, void *buf, int offset, int len);
200 void fat_close(void);