FAT big endian changes

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1419 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
This commit is contained in:
Greg Watson 2004-03-17 17:03:02 +00:00
parent f6d05f501e
commit 582231ed01
2 changed files with 61 additions and 41 deletions

View File

@ -42,25 +42,27 @@ struct fat_bpb {
__u8 reserved_sects[2]; /* reserved sectors */ __u8 reserved_sects[2]; /* reserved sectors */
__u8 num_fats; /* number of FATs */ __u8 num_fats; /* number of FATs */
__u8 dir_entries[2]; /* root directory entries */ __u8 dir_entries[2]; /* root directory entries */
__u8 short_sectors[2]; /* number of sectors */ __u8 short_sectors[2];/* number of sectors */
__u8 media; /* media code (unused) */ __u8 media; /* media code (unused) */
__u16 fat_length; /* sectors/FAT */ __u8 fat_length[2]; /* sectors/FAT */
__u16 secs_track; /* sectors per track */ __u8 secs_track[2]; /* sectors per track */
__u16 heads; /* number of heads */ __u8 heads[2]; /* number of heads */
__u32 hidden; /* hidden sectors (unused) */ __u8 hidden[2]; /* hidden sectors (unused) */
__u32 long_sectors; /* number of sectors (if short_sectors == 0) */ __u8 long_sectors[2];/* number of sectors (if short_sectors == 0) */
/* The following fields are only used by FAT32 */ /* The following fields are only used by FAT32 */
__u32 fat32_length; /* sectors/FAT */ __u8 fat32_length[2];/* sectors/FAT */
__u16 flags; /* bit 8: fat mirroring, low 4: active fat */ __u8 flags[2]; /* bit 8: fat mirroring, low 4: active fat */
__u8 version[2]; /* major, minor filesystem version */ __u8 version[2]; /* major, minor filesystem version */
__u32 root_cluster; /* first cluster in root directory */ __u8 root_cluster[4];/* first cluster in root directory */
__u16 info_sector; /* filesystem info sector */ __u8 info_sector[2]; /* filesystem info sector */
__u16 backup_boot; /* backup boot sector */ __u8 backup_boot[2]; /* backup boot sector */
__u16 reserved2[6]; /* Unused */ __u8 reserved2[12]; /* Unused */
}; };
#define FAT_CVT_U16(bytarr) (* (__u16*)(bytarr)) #define FAT_CVT_U8(byte) (* (__u8*)(byte))
#define FAT_CVT_U16(bytarr) le16_to_cpu(* (__u16*)(bytarr))
#define FAT_CVT_U32(bytarr) le32_to_cpu(* (__u32*)(bytarr))
/* /*
* Defines how to differentiate a 12-bit and 16-bit FAT. * Defines how to differentiate a 12-bit and 16-bit FAT.
@ -84,17 +86,17 @@ struct fat_bpb {
#define FAT_DIRENTRY_LENGTH 32 #define FAT_DIRENTRY_LENGTH 32
#define FAT_DIRENTRY_ATTRIB(entry) \ #define FAT_DIRENTRY_ATTRIB(entry) \
(*((unsigned char *) (entry+11))) FAT_CVT_U8(entry+11)
#define FAT_DIRENTRY_VALID(entry) \ #define FAT_DIRENTRY_VALID(entry) \
( ((*((unsigned char *) entry)) != 0) \ ( (FAT_CVT_U8(entry) != 0) \
&& ((*((unsigned char *) entry)) != 0xE5) \ && (FAT_CVT_U8(entry) != 0xE5) \
&& !(FAT_DIRENTRY_ATTRIB(entry) & FAT_ATTRIB_NOT_OK_MASK) ) && !(FAT_DIRENTRY_ATTRIB(entry) & FAT_ATTRIB_NOT_OK_MASK) )
#define FAT_DIRENTRY_FIRST_CLUSTER(entry) \ #define FAT_DIRENTRY_FIRST_CLUSTER(entry) \
((*((unsigned short *) (entry+26)))+(*((unsigned short *) (entry+20)) << 16)) (FAT_CVT_U16(entry+26)+(FAT_CVT_U16(entry+20) << 16))
#define FAT_DIRENTRY_FILELENGTH(entry) \ #define FAT_DIRENTRY_FILELENGTH(entry) \
(*((unsigned long *) (entry+28))) FAT_CVT_U32(entry+28)
#define FAT_LONGDIR_ID(entry) \ #define FAT_LONGDIR_ID(entry) \
(*((unsigned char *) (entry))) FAT_CVT_U8(entry)
#define FAT_LONGDIR_ALIASCHECKSUM(entry) \ #define FAT_LONGDIR_ALIASCHECKSUM(entry) \
(*((unsigned char *) (entry+13))) FAT_CVT_U8(entry+13)

View File

@ -17,8 +17,11 @@
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/ */
#include <console/console.h>
#include <string.h>
#include <fs/fs.h> #include <fs/fs.h>
#include <fs/fat.h> #include <fs/fat.h>
#include <arch/byteorder.h>
struct fat_superblock struct fat_superblock
{ {
@ -72,8 +75,6 @@ __ilog2(unsigned long x)
static __inline__ unsigned long static __inline__ unsigned long
log2(unsigned long x) log2(unsigned long x)
{ {
if ((x = ~x) == 0)
return 32;
return __ilog2(x & -x); return __ilog2(x & -x);
} }
#endif #endif
@ -98,24 +99,36 @@ fat_mount (void)
zero division. */ zero division. */
if (bpb.sects_per_clust == 0) if (bpb.sects_per_clust == 0)
return 0; return 0;
FAT_SUPER->sectsize_bits = log2 (FAT_CVT_U16 (bpb.bytes_per_sect)); FAT_SUPER->sectsize_bits = log2(FAT_CVT_U16(bpb.bytes_per_sect));
FAT_SUPER->clustsize_bits FAT_SUPER->clustsize_bits
= FAT_SUPER->sectsize_bits + log2 (bpb.sects_per_clust); = FAT_SUPER->sectsize_bits + log2(bpb.sects_per_clust);
printk_debug("BytsPerSec = %d\n", FAT_CVT_U16(bpb.bytes_per_sect));
printk_debug("SecPerClus = %d\n", bpb.sects_per_clust);
/* Fill in info about super block */ /* Fill in info about super block */
FAT_SUPER->num_sectors = FAT_CVT_U16 (bpb.short_sectors) FAT_SUPER->num_sectors = FAT_CVT_U16(bpb.short_sectors)
? FAT_CVT_U16 (bpb.short_sectors) : bpb.long_sectors; ? FAT_CVT_U16(bpb.short_sectors) : FAT_CVT_U32(bpb.long_sectors);
printk_debug("TotSec16 = %d\n", FAT_CVT_U16(bpb.short_sectors));
printk_debug("TotSec32 = %d\n", FAT_CVT_U32(bpb.long_sectors));
/* FAT offset and length */ /* FAT offset and length */
FAT_SUPER->fat_offset = FAT_CVT_U16 (bpb.reserved_sects); FAT_SUPER->fat_offset = FAT_CVT_U16(bpb.reserved_sects);
FAT_SUPER->fat_length = FAT_SUPER->fat_length = FAT_CVT_U16(bpb.fat_length)
bpb.fat_length ? bpb.fat_length : bpb.fat32_length; ? FAT_CVT_U16(bpb.fat_length) : FAT_CVT_U32(bpb.fat32_length);
printk_debug("RsvdSecCnt = %d\n", FAT_CVT_U16(bpb.reserved_sects));
printk_debug("FATSx16 = %d\n", FAT_CVT_U16(bpb.fat_length));
printk_debug("FATSx32 = %d\n", FAT_CVT_U32(bpb.fat32_length));
/* Rootdir offset and length for FAT12/16 */ /* Rootdir offset and length for FAT12/16 */
FAT_SUPER->root_offset = FAT_SUPER->root_offset =
FAT_SUPER->fat_offset + bpb.num_fats * FAT_SUPER->fat_length; FAT_SUPER->fat_offset + bpb.num_fats * FAT_SUPER->fat_length;
FAT_SUPER->root_max = FAT_DIRENTRY_LENGTH * FAT_CVT_U16(bpb.dir_entries); FAT_SUPER->root_max = FAT_DIRENTRY_LENGTH * FAT_CVT_U16(bpb.dir_entries);
printk_debug("RootEntCnt = %d\n", FAT_CVT_U16(bpb.dir_entries));
/* Data offset and number of clusters */ /* Data offset and number of clusters */
FAT_SUPER->data_offset = FAT_SUPER->data_offset =
@ -125,24 +138,27 @@ fat_mount (void)
2 + ((FAT_SUPER->num_sectors - FAT_SUPER->data_offset) 2 + ((FAT_SUPER->num_sectors - FAT_SUPER->data_offset)
/ bpb.sects_per_clust); / bpb.sects_per_clust);
FAT_SUPER->sects_per_clust = bpb.sects_per_clust; FAT_SUPER->sects_per_clust = bpb.sects_per_clust;
if (!bpb.fat_length) if (!bpb.fat_length)
{ {
/* This is a FAT32 */ /* This is a FAT32 */
if (FAT_CVT_U16(bpb.dir_entries)) if (FAT_CVT_U16(bpb.dir_entries))
return 0; return 0;
if (bpb.flags & 0x0080) printk_debug("We seem to be FAT32\n");
printk_debug("ExtFlags = 0x%x\n", FAT_CVT_U16(bpb.flags));
printk_debug("RootClus = %d\n", FAT_CVT_U32(bpb.root_cluster));
if (FAT_CVT_U16(bpb.flags) & 0x0080)
{ {
/* FAT mirroring is disabled, get active FAT */ /* FAT mirroring is disabled, get active FAT */
int active_fat = bpb.flags & 0x000f; int active_fat = FAT_CVT_U16(bpb.flags) & 0x000f;
if (active_fat >= bpb.num_fats) if (active_fat >= bpb.num_fats)
return 0; return 0;
FAT_SUPER->fat_offset += active_fat * FAT_SUPER->fat_length; FAT_SUPER->fat_offset += active_fat * FAT_SUPER->fat_length;
} }
FAT_SUPER->fat_size = 8; FAT_SUPER->fat_size = 8;
FAT_SUPER->root_cluster = bpb.root_cluster; FAT_SUPER->root_cluster = FAT_CVT_U32(bpb.root_cluster);
/* Yes the following is correct. FAT32 should be called FAT28 :) */ /* Yes the following is correct. FAT32 should be called FAT28 :) */
FAT_SUPER->clust_eof_marker = 0xffffff8; FAT_SUPER->clust_eof_marker = 0xffffff8;
@ -152,6 +168,7 @@ fat_mount (void)
if (!FAT_SUPER->root_max) if (!FAT_SUPER->root_max)
return 0; return 0;
printk_debug("We seem to be FAT12/16\n");
FAT_SUPER->root_cluster = -1; FAT_SUPER->root_cluster = -1;
if (FAT_SUPER->num_clust > FAT_MAX_12BIT_CLUST) if (FAT_SUPER->num_clust > FAT_MAX_12BIT_CLUST)
{ {
@ -165,7 +182,6 @@ fat_mount (void)
} }
} }
/* Now do some sanity checks */ /* Now do some sanity checks */
if (FAT_CVT_U16(bpb.bytes_per_sect) != (1 << FAT_SUPER->sectsize_bits) if (FAT_CVT_U16(bpb.bytes_per_sect) != (1 << FAT_SUPER->sectsize_bits)
@ -183,19 +199,21 @@ fat_mount (void)
sizeof(first_fat), (char *)&first_fat)) sizeof(first_fat), (char *)&first_fat))
return 0; return 0;
printk_debug("Media = 0x%x\n", bpb.media);
if (FAT_SUPER->fat_size == 8) if (FAT_SUPER->fat_size == 8)
{ {
first_fat &= 0x0fffffff; first_fat = le32_to_cpu(first_fat) & 0x0fffffff;
magic = 0x0fffff00; magic = 0x0fffff00;
} }
else if (FAT_SUPER->fat_size == 4) else if (FAT_SUPER->fat_size == 4)
{ {
first_fat &= 0x0000ffff; first_fat = le32_to_cpu(first_fat) & 0x0000ffff;
magic = 0xff00; magic = 0xff00;
} }
else else
{ {
first_fat &= 0x00000fff; first_fat = le32_to_cpu(first_fat) & 0x00000fff;
magic = 0x0f00; magic = 0x0f00;
} }
@ -255,7 +273,7 @@ fat_read (char *buf, int len)
if (!devread (sector, 0, FAT_CACHE_SIZE, (char*) FAT_BUF)) if (!devread (sector, 0, FAT_CACHE_SIZE, (char*) FAT_BUF))
return 0; return 0;
} }
next_cluster = * (unsigned long *) (FAT_BUF + (cached_pos >> 1)); next_cluster = FAT_CVT_U32(FAT_BUF + (cached_pos >> 1));
if (FAT_SUPER->fat_size == 3) if (FAT_SUPER->fat_size == 3)
{ {
if (cached_pos & 1) if (cached_pos & 1)
@ -288,7 +306,7 @@ fat_read (char *buf, int len)
devread(sector, offset, size, buf); devread(sector, offset, size, buf);
disk_read_func = NULL; disk_read_func = 0;
len -= size; len -= size;
buf += size; buf += size;
@ -317,7 +335,7 @@ fat_dir (char *dirname)
{ 1, 3, 5, 7, 9, 14, 16, 18, 20, 22, 24, 28, 30 }; { 1, 3, 5, 7, 9, 14, 16, 18, 20, 22, 24, 28, 30 };
int slot = -2; int slot = -2;
int alias_checksum = -1; int alias_checksum = -1;
FAT_SUPER->file_cluster = FAT_SUPER->root_cluster; FAT_SUPER->file_cluster = FAT_SUPER->root_cluster;
filepos = 0; filepos = 0;
FAT_SUPER->current_cluster_num = MAXINT; FAT_SUPER->current_cluster_num = MAXINT;