xref: /openbmc/u-boot/include/fat.h (revision ca831f4933dc68d9ed1b6399cbda90068c520005)
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   * SPDX-License-Identifier:	GPL-2.0+
8   */
9  
10  #ifndef _FAT_H_
11  #define _FAT_H_
12  
13  #include <asm/byteorder.h>
14  
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
20  
21  #ifndef CONFIG_FS_FAT_MAX_CLUSTSIZE
22  #define CONFIG_FS_FAT_MAX_CLUSTSIZE 65536
23  #endif
24  #define MAX_CLUSTSIZE	CONFIG_FS_FAT_MAX_CLUSTSIZE
25  
26  #define DIRENTSPERBLOCK	(mydata->sect_size / sizeof(dir_entry))
27  #define DIRENTSPERCLUST	((mydata->clust_size * mydata->sect_size) / \
28  			 sizeof(dir_entry))
29  
30  #define FATBUFBLOCKS	6
31  #define FATBUFSIZE	(mydata->sect_size * FATBUFBLOCKS)
32  #define FAT12BUFSIZE	((FATBUFSIZE*2)/3)
33  #define FAT16BUFSIZE	(FATBUFSIZE/2)
34  #define FAT32BUFSIZE	(FATBUFSIZE/4)
35  
36  
37  /* Filesystem identifiers */
38  #define FAT12_SIGN	"FAT12   "
39  #define FAT16_SIGN	"FAT16   "
40  #define FAT32_SIGN	"FAT32   "
41  #define SIGNLEN		8
42  
43  /* File attributes */
44  #define ATTR_RO	1
45  #define ATTR_HIDDEN	2
46  #define ATTR_SYS	4
47  #define ATTR_VOLUME	8
48  #define ATTR_DIR	16
49  #define ATTR_ARCH	32
50  
51  #define ATTR_VFAT	(ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME)
52  
53  #define DELETED_FLAG	((char)0xe5) /* Marks deleted files when in name[0] */
54  #define aRING		0x05	     /* Used as special character in name[0] */
55  
56  /*
57   * Indicates that the entry is the last long entry in a set of long
58   * dir entries
59   */
60  #define LAST_LONG_ENTRY_MASK	0x40
61  
62  /* Flags telling whether we should read a file or list a directory */
63  #define LS_NO		0
64  #define LS_YES		1
65  #define LS_DIR		1
66  #define LS_ROOT		2
67  
68  #define ISDIRDELIM(c)	((c) == '/' || (c) == '\\')
69  
70  #define FSTYPE_NONE	(-1)
71  
72  #if defined(__linux__) && defined(__KERNEL__)
73  #define FAT2CPU16	le16_to_cpu
74  #define FAT2CPU32	le32_to_cpu
75  #else
76  #if __LITTLE_ENDIAN
77  #define FAT2CPU16(x)	(x)
78  #define FAT2CPU32(x)	(x)
79  #else
80  #define FAT2CPU16(x)	((((x) & 0x00ff) << 8) | (((x) & 0xff00) >> 8))
81  #define FAT2CPU32(x)	((((x) & 0x000000ff) << 24)  |	\
82  			 (((x) & 0x0000ff00) << 8)  |	\
83  			 (((x) & 0x00ff0000) >> 8)  |	\
84  			 (((x) & 0xff000000) >> 24))
85  #endif
86  #endif
87  
88  #define START(dent)	(FAT2CPU16((dent)->start) \
89  			+ (mydata->fatsize != 32 ? 0 : \
90  			  (FAT2CPU16((dent)->starthi) << 16)))
91  #define IS_LAST_CLUST(x, fatsize) ((x) >= ((fatsize) != 32 ? \
92  					((fatsize) != 16 ? 0xff8 : 0xfff8) : \
93  					0xffffff8))
94  #define CHECK_CLUST(x, fatsize) ((x) <= 1 || \
95  				(x) >= ((fatsize) != 32 ? \
96  					((fatsize) != 16 ? 0xff0 : 0xfff0) : \
97  					0xffffff0))
98  
99  typedef struct boot_sector {
100  	__u8	ignored[3];	/* Bootstrap code */
101  	char	system_id[8];	/* Name of fs */
102  	__u8	sector_size[2];	/* Bytes/sector */
103  	__u8	cluster_size;	/* Sectors/cluster */
104  	__u16	reserved;	/* Number of reserved sectors */
105  	__u8	fats;		/* Number of FATs */
106  	__u8	dir_entries[2];	/* Number of root directory entries */
107  	__u8	sectors[2];	/* Number of sectors */
108  	__u8	media;		/* Media code */
109  	__u16	fat_length;	/* Sectors/FAT */
110  	__u16	secs_track;	/* Sectors/track */
111  	__u16	heads;		/* Number of heads */
112  	__u32	hidden;		/* Number of hidden sectors */
113  	__u32	total_sect;	/* Number of sectors (if sectors == 0) */
114  
115  	/* FAT32 only */
116  	__u32	fat32_length;	/* Sectors/FAT */
117  	__u16	flags;		/* Bit 8: fat mirroring, low 4: active fat */
118  	__u8	version[2];	/* Filesystem version */
119  	__u32	root_cluster;	/* First cluster in root directory */
120  	__u16	info_sector;	/* Filesystem info sector */
121  	__u16	backup_boot;	/* Backup boot sector */
122  	__u16	reserved2[6];	/* Unused */
123  } boot_sector;
124  
125  typedef struct volume_info
126  {
127  	__u8 drive_number;	/* BIOS drive number */
128  	__u8 reserved;		/* Unused */
129  	__u8 ext_boot_sign;	/* 0x29 if fields below exist (DOS 3.3+) */
130  	__u8 volume_id[4];	/* Volume ID number */
131  	char volume_label[11];	/* Volume label */
132  	char fs_type[8];	/* Typically FAT12, FAT16, or FAT32 */
133  	/* Boot code comes next, all but 2 bytes to fill up sector */
134  	/* Boot sign comes last, 2 bytes */
135  } volume_info;
136  
137  typedef struct dir_entry {
138  	char	name[8],ext[3];	/* Name and extension */
139  	__u8	attr;		/* Attribute bits */
140  	__u8	lcase;		/* Case for base and extension */
141  	__u8	ctime_ms;	/* Creation time, milliseconds */
142  	__u16	ctime;		/* Creation time */
143  	__u16	cdate;		/* Creation date */
144  	__u16	adate;		/* Last access date */
145  	__u16	starthi;	/* High 16 bits of cluster in FAT32 */
146  	__u16	time,date,start;/* Time, date and first cluster */
147  	__u32	size;		/* File size in bytes */
148  } dir_entry;
149  
150  typedef struct dir_slot {
151  	__u8	id;		/* Sequence number for slot */
152  	__u8	name0_4[10];	/* First 5 characters in name */
153  	__u8	attr;		/* Attribute byte */
154  	__u8	reserved;	/* Unused */
155  	__u8	alias_checksum;/* Checksum for 8.3 alias */
156  	__u8	name5_10[12];	/* 6 more characters in name */
157  	__u16	start;		/* Unused */
158  	__u8	name11_12[4];	/* Last 2 characters in name */
159  } dir_slot;
160  
161  /*
162   * Private filesystem parameters
163   *
164   * Note: FAT buffer has to be 32 bit aligned
165   * (see FAT32 accesses)
166   */
167  typedef struct {
168  	__u8	*fatbuf;	/* Current FAT buffer */
169  	int	fatsize;	/* Size of FAT in bits */
170  	__u32	fatlength;	/* Length of FAT in sectors */
171  	__u16	fat_sect;	/* Starting sector of the FAT */
172  	__u32	rootdir_sect;	/* Start sector of root directory */
173  	__u16	sect_size;	/* Size of sectors in bytes */
174  	__u16	clust_size;	/* Size of clusters in sectors */
175  	int	data_begin;	/* The sector of the first cluster, can be negative */
176  	int	fatbufnum;	/* Used by get_fatent, init to -1 */
177  } fsdata;
178  
179  typedef int	(file_detectfs_func)(void);
180  typedef int	(file_ls_func)(const char *dir);
181  typedef int	(file_read_func)(const char *filename, void *buffer,
182  				 int maxsize);
183  
184  struct filesystem {
185  	file_detectfs_func	*detect;
186  	file_ls_func		*ls;
187  	file_read_func		*read;
188  	const char		name[12];
189  };
190  
191  /* FAT tables */
192  file_detectfs_func	file_fat_detectfs;
193  file_ls_func		file_fat_ls;
194  file_read_func		file_fat_read;
195  
196  /* Currently this doesn't check if the dir exists or is valid... */
197  int file_cd(const char *path);
198  int file_fat_detectfs(void);
199  int file_fat_ls(const char *dir);
200  int fat_exists(const char *filename);
201  int fat_size(const char *filename, loff_t *size);
202  int file_fat_read_at(const char *filename, loff_t pos, void *buffer,
203  		     loff_t maxsize, loff_t *actread);
204  int file_fat_read(const char *filename, void *buffer, int maxsize);
205  const char *file_getfsname(int idx);
206  int fat_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info);
207  int fat_register_device(block_dev_desc_t *dev_desc, int part_no);
208  
209  int file_fat_write(const char *filename, void *buf, loff_t offset, loff_t len,
210  		   loff_t *actwrite);
211  int fat_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
212  		  loff_t *actread);
213  void fat_close(void);
214  #endif /* _FAT_H_ */
215