DRESULT disk_write (
BYTE pdrv, /* Physical drive nmuber (0) */
const BYTE *buff, /* Data to be written */
DWORD sector, /* Sector number (LBA) */
UINT count /* Sector count (1..128) */
)
{
if (pdrv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
/* Issue Write Setor(s) command */
if (!issue_rwcmd(CMD_WRITE, sector, count)) return RES_ERROR;
/* Send data blocks */
do {
if (!wait_stat(2000, DRQ)) return RES_ERROR;
write_block(buff);
buff += 512;
} while (--count);
/* Wait for end of write process */
if (!wait_stat(1000, 0)) return RES_ERROR;
read_ata(REG_ALTSTAT);
read_ata(REG_STATUS);
return RES_OK;
}
DRESULT disk_ioctl (
BYTE pdrv, /* Physical drive nmuber (0) */
BYTE cmd, /* Control code */
void *buff /* Buffer to send/receive data block */
)
{
BYTE n, w, ofs, dl, dh, *ptr = (BYTE*)buff;
if (pdrv) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
switch (cmd) {
case GET_BLOCK_SIZE : /* Get erase block size in sectors (DWORD) */
*(DWORD*)buff = 128;
return RES_OK;
case CTRL_SYNC : /* Nothing to do */
return RES_OK;
}
switch (cmd) {
case GET_SECTOR_COUNT :
ofs = 60; w = 2; n = 0;
break;
case ATA_GET_REV : /* Get firmware revision (8 chars) */
ofs = 23; w = 4; n = 4;
break;
case ATA_GET_MODEL : /* Get model name (40 chars) */
ofs = 27; w = 20; n = 20;
break;
case ATA_GET_SN : /* Get serial number (20 chars) */
ofs = 10; w = 10; n = 10;
break;
default:
return RES_PARERR;
}
if (!wait_stat(1000, DRDY)) return RES_ERROR;
write_ata(REG_COMMAND, CMD_IDENTIFY); /* Get device ID data block */
if (!wait_stat(1000, DRQ)) return RES_ERROR; /* Wait for data ready */
read_block_part(ptr, ofs, w); /* Get a part of data block */
while (n--) { /* Swap byte order */
dl = *ptr++; dh = *ptr--;
*ptr++ = dh; *ptr++ = dl;
}
read_ata(REG_ALTSTAT);
read_ata(REG_STATUS);
return RES_OK;
}
static struct fat_dir_entry *get_dir_entry(struct fat32_fs *fs,
unsigned int rel_cluster)
{
struct fat_dir_entry *dir = kmalloc(sizeof(struct fat_dir_entry));
if (!read_ata(fs->d, abs_cluster(fs, rel_cluster), dir,
//if (!read_ata(fs->d, rel_cluster, dir,
sizeof(struct fat_dir_entry))) {
kfree(dir);
kprintf("Could not find on disk\n");
return NULL;
}
/* The root entry will have VOLUME_ID and not DIRECTORY set */
if (dir->attr & ATTR_VOLUME_ID) {
return dir;
} else {
if (dir->dirname[0] == 0x00 || dir->dirname[0] == 0xE5) {
kprintf("Unused entry\n");
return NULL;
} else if (!(dir->attr & ATTR_DIRECTORY)) {
kprintf("Entry exists, but isn't a dir\n");
return NULL;
} else {
return dir;
}
}
}
static unsigned char *read_fat(struct fat32_fs *fs, unsigned int start_sector)
{
unsigned char *table = kmalloc(FAT32_CLUSTER_SIZE);
if (!read_ata(fs->d, start_sector, table, FAT32_CLUSTER_SIZE)) {
kprintf("Couldn't read file allocation table\n");
return NULL;
}
return table;
}
static
int wait_stat ( /* 0:Timeout or or ERR goes 1 */
UINT ms,
BYTE bit
)
{
BYTE s;
set_timer(ms);
do {
s = read_ata(REG_STATUS); /* Get status */
if (!get_timer() || (s & ERR)) return 0; /* Abort when timeout or error occured */
} while ((s & BSY) || (bit && !(bit & s))); /* Wait for BSY goes 0 and the bit goes 1 */
read_ata(REG_ALTSTAT);
return 1;
}
DRESULT disk_read (
BYTE pdrv, /* Physical drive nmuber (0) */
BYTE *buff, /* Data buffer to store read data */
DWORD sector, /* Sector number (LBA) */
UINT count /* Sector count (1..128) */
)
{
if (pdrv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
/* Issue Read Setor(s) command */
if (!issue_rwcmd(CMD_READ, sector, count)) return RES_ERROR;
/* Receive data blocks */
do {
if (!wait_stat(2000, DRQ)) return RES_ERROR;
read_block(buff);
buff += 512;
} while (--count);
read_ata(REG_ALTSTAT);
read_ata(REG_STATUS);
return RES_OK;
}
struct fat32_fs *mount_fat32(struct drive *d)
{
struct fat_boot_sector *bs = kmalloc(512);
if (!read_ata(d, 0, bs, 512)) {
kprintf("Failed to read sector 0\n");
kfree(bs);
return NULL;
}
/* Treat bootjmp as magic */
if (bs->bootjmp[0] != 0xEB && bs->bootjmp[0] != 0xE9) {
kprintf("There is no FAT32 file system here\n");
kfree(bs);
return NULL;
}
/* null-terminate all of the string fields */
bs->oem_name[7] = '\0';
bs->fat32.volume_label[10] = '\0';
bs->fat32.fat_type_label[5] = '\0';
/* Verify this is FAT32 */
if (strcmp((char *)bs->fat32.fat_type_label, "FAT32") != 0) {
kprintf("There is a FAT file system here, but it's not FAT32: `%s`\n",
bs->fat32.fat_type_label);
return NULL;
}
/* Populate the file system struct */
struct fat32_fs *fs = kmalloc(sizeof(struct fat32_fs));
fs->d = d;
fs->bs = bs;
fs->first_data_sector = bs->reserved_sector_count +
(bs->table_count * bs->table_size_16);
fs->table = read_fat(fs, fs->first_data_sector);
kprintf("Mounted FAT32 file system with label `%s`\n",
bs->fat32.volume_label);
return fs;
}
