xref: /openbmc/u-boot/include/fat.h (revision bf48fcb6)
1 /*
2  * R/O (V)FAT 12/16/32 filesystem implementation by Marcus Sundberg
3  *
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
6  *
7  * See file CREDITS for list of people who contributed to this
8  * project.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 of
13  * the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
23  * MA 02111-1307 USA
24  *
25  */
26 
27 #ifndef _FAT_H_
28 #define _FAT_H_
29 
30 #include <asm/byteorder.h>
31 
32 #define CONFIG_SUPPORT_VFAT
33 /* Maximum Long File Name length supported here is 128 UTF-16 code units */
34 #define VFAT_MAXLEN_BYTES	256 /* Maximum LFN buffer in bytes */
35 #define VFAT_MAXSEQ		9   /* Up to 9 of 13 2-byte UTF-16 entries */
36 #define PREFETCH_BLOCKS		2
37 
38 #define MAX_CLUSTSIZE	65536
39 #define DIRENTSPERBLOCK	(mydata->sect_size / sizeof(dir_entry))
40 #define DIRENTSPERCLUST	((mydata->clust_size * mydata->sect_size) / \
41 			 sizeof(dir_entry))
42 
43 #define FATBUFBLOCKS	6
44 #define FATBUFSIZE	(mydata->sect_size * FATBUFBLOCKS)
45 #define FAT12BUFSIZE	((FATBUFSIZE*2)/3)
46 #define FAT16BUFSIZE	(FATBUFSIZE/2)
47 #define FAT32BUFSIZE	(FATBUFSIZE/4)
48 
49 
50 /* Filesystem identifiers */
51 #define FAT12_SIGN	"FAT12   "
52 #define FAT16_SIGN	"FAT16   "
53 #define FAT32_SIGN	"FAT32   "
54 #define SIGNLEN		8
55 
56 /* File attributes */
57 #define ATTR_RO	1
58 #define ATTR_HIDDEN	2
59 #define ATTR_SYS	4
60 #define ATTR_VOLUME	8
61 #define ATTR_DIR	16
62 #define ATTR_ARCH	32
63 
64 #define ATTR_VFAT	(ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME)
65 
66 #define DELETED_FLAG	((char)0xe5) /* Marks deleted files when in name[0] */
67 #define aRING		0x05	     /* Used as special character in name[0] */
68 
69 /*
70  * Indicates that the entry is the last long entry in a set of long
71  * dir entries
72  */
73 #define LAST_LONG_ENTRY_MASK	0x40
74 
75 /* Flags telling whether we should read a file or list a directory */
76 #define LS_NO		0
77 #define LS_YES		1
78 #define LS_DIR		1
79 #define LS_ROOT		2
80 
81 #define ISDIRDELIM(c)	((c) == '/' || (c) == '\\')
82 
83 #define FSTYPE_NONE	(-1)
84 
85 #if defined(__linux__) && defined(__KERNEL__)
86 #define FAT2CPU16	le16_to_cpu
87 #define FAT2CPU32	le32_to_cpu
88 #else
89 #if __LITTLE_ENDIAN
90 #define FAT2CPU16(x)	(x)
91 #define FAT2CPU32(x)	(x)
92 #else
93 #define FAT2CPU16(x)	((((x) & 0x00ff) << 8) | (((x) & 0xff00) >> 8))
94 #define FAT2CPU32(x)	((((x) & 0x000000ff) << 24)  |	\
95 			 (((x) & 0x0000ff00) << 8)  |	\
96 			 (((x) & 0x00ff0000) >> 8)  |	\
97 			 (((x) & 0xff000000) >> 24))
98 #endif
99 #endif
100 
101 #define TOLOWER(c)	if((c) >= 'A' && (c) <= 'Z'){(c)+=('a' - 'A');}
102 #define TOUPPER(c)	if ((c) >= 'a' && (c) <= 'z') \
103 				(c) -= ('a' - 'A');
104 #define START(dent)	(FAT2CPU16((dent)->start) \
105 			+ (mydata->fatsize != 32 ? 0 : \
106 			  (FAT2CPU16((dent)->starthi) << 16)))
107 #define CHECK_CLUST(x, fatsize) ((x) <= 1 || \
108 				(x) >= ((fatsize) != 32 ? 0xfff0 : 0xffffff0))
109 
110 typedef struct boot_sector {
111 	__u8	ignored[3];	/* Bootstrap code */
112 	char	system_id[8];	/* Name of fs */
113 	__u8	sector_size[2];	/* Bytes/sector */
114 	__u8	cluster_size;	/* Sectors/cluster */
115 	__u16	reserved;	/* Number of reserved sectors */
116 	__u8	fats;		/* Number of FATs */
117 	__u8	dir_entries[2];	/* Number of root directory entries */
118 	__u8	sectors[2];	/* Number of sectors */
119 	__u8	media;		/* Media code */
120 	__u16	fat_length;	/* Sectors/FAT */
121 	__u16	secs_track;	/* Sectors/track */
122 	__u16	heads;		/* Number of heads */
123 	__u32	hidden;		/* Number of hidden sectors */
124 	__u32	total_sect;	/* Number of sectors (if sectors == 0) */
125 
126 	/* FAT32 only */
127 	__u32	fat32_length;	/* Sectors/FAT */
128 	__u16	flags;		/* Bit 8: fat mirroring, low 4: active fat */
129 	__u8	version[2];	/* Filesystem version */
130 	__u32	root_cluster;	/* First cluster in root directory */
131 	__u16	info_sector;	/* Filesystem info sector */
132 	__u16	backup_boot;	/* Backup boot sector */
133 	__u16	reserved2[6];	/* Unused */
134 } boot_sector;
135 
136 typedef struct volume_info
137 {
138 	__u8 drive_number;	/* BIOS drive number */
139 	__u8 reserved;		/* Unused */
140 	__u8 ext_boot_sign;	/* 0x29 if fields below exist (DOS 3.3+) */
141 	__u8 volume_id[4];	/* Volume ID number */
142 	char volume_label[11];	/* Volume label */
143 	char fs_type[8];	/* Typically FAT12, FAT16, or FAT32 */
144 	/* Boot code comes next, all but 2 bytes to fill up sector */
145 	/* Boot sign comes last, 2 bytes */
146 } volume_info;
147 
148 typedef struct dir_entry {
149 	char	name[8],ext[3];	/* Name and extension */
150 	__u8	attr;		/* Attribute bits */
151 	__u8	lcase;		/* Case for base and extension */
152 	__u8	ctime_ms;	/* Creation time, milliseconds */
153 	__u16	ctime;		/* Creation time */
154 	__u16	cdate;		/* Creation date */
155 	__u16	adate;		/* Last access date */
156 	__u16	starthi;	/* High 16 bits of cluster in FAT32 */
157 	__u16	time,date,start;/* Time, date and first cluster */
158 	__u32	size;		/* File size in bytes */
159 } dir_entry;
160 
161 typedef struct dir_slot {
162 	__u8	id;		/* Sequence number for slot */
163 	__u8	name0_4[10];	/* First 5 characters in name */
164 	__u8	attr;		/* Attribute byte */
165 	__u8	reserved;	/* Unused */
166 	__u8	alias_checksum;/* Checksum for 8.3 alias */
167 	__u8	name5_10[12];	/* 6 more characters in name */
168 	__u16	start;		/* Unused */
169 	__u8	name11_12[4];	/* Last 2 characters in name */
170 } dir_slot;
171 
172 /*
173  * Private filesystem parameters
174  *
175  * Note: FAT buffer has to be 32 bit aligned
176  * (see FAT32 accesses)
177  */
178 typedef struct {
179 	__u8	*fatbuf;	/* Current FAT buffer */
180 	int	fatsize;	/* Size of FAT in bits */
181 	__u32	fatlength;	/* Length of FAT in sectors */
182 	__u16	fat_sect;	/* Starting sector of the FAT */
183 	__u32	rootdir_sect;	/* Start sector of root directory */
184 	__u16	sect_size;	/* Size of sectors in bytes */
185 	__u16	clust_size;	/* Size of clusters in sectors */
186 	int	data_begin;	/* The sector of the first cluster, can be negative */
187 	int	fatbufnum;	/* Used by get_fatent, init to -1 */
188 } fsdata;
189 
190 typedef int	(file_detectfs_func)(void);
191 typedef int	(file_ls_func)(const char *dir);
192 typedef long	(file_read_func)(const char *filename, void *buffer,
193 				 unsigned long maxsize);
194 
195 struct filesystem {
196 	file_detectfs_func	*detect;
197 	file_ls_func		*ls;
198 	file_read_func		*read;
199 	const char		name[12];
200 };
201 
202 /* FAT tables */
203 file_detectfs_func	file_fat_detectfs;
204 file_ls_func		file_fat_ls;
205 file_read_func		file_fat_read;
206 
207 /* Currently this doesn't check if the dir exists or is valid... */
208 int file_cd(const char *path);
209 int file_fat_detectfs(void);
210 int file_fat_ls(const char *dir);
211 long file_fat_read_at(const char *filename, unsigned long pos, void *buffer,
212 		      unsigned long maxsize);
213 long file_fat_read(const char *filename, void *buffer, unsigned long maxsize);
214 const char *file_getfsname(int idx);
215 int fat_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info);
216 int fat_register_device(block_dev_desc_t *dev_desc, int part_no);
217 
218 int file_fat_write(const char *filename, void *buffer, unsigned long maxsize);
219 #endif /* _FAT_H_ */
220