/**
* We try to read tracks, but if we get too many errors, we
* go back to reading just one sector at a time.
*
* This means we should be able to read a sector even if there
* are other bad sectors on this track.
*
* @see rw_interrupt
*/
inline void setup_rw_floppy(void) {
setup_DMA();
do_floppy = rw_interrupt;
output_byte(command);
if (command != FD_FORMAT) {
if (read_track) {
output_byte(current_drive);
output_byte(track);
output_byte(0);
output_byte(1);
} else {
output_byte(head<<2 | current_drive);
output_byte(track);
output_byte(head);
output_byte(sector);
}
output_byte(2); /* sector size = 512 */
output_byte(floppy->sect);
output_byte(floppy->gap);
output_byte(0xFF); /* sector size (0xff when n!=0 ?) */
} else {
output_byte(head<<2 | current_drive);
output_byte(2);
output_byte(floppy->sect);
output_byte(floppy->fmt_gap);
output_byte(FD_FILL_BYTE);
}
if (reset)
redo_fd_request();
}
/*
* And now, it's time to implenent the read or write function, that's
* all the floppy driver mean!
*
* Read/Write one sector once.
*/
static int floppy_rw(int sector, char *buf, int command)
{
int head;
char *dma_buffer = buf;
static char tmp_dma_buffer[512];
//LOG("TMP dma buffer: %p\n", tmp_dma_buffer);
lba_to_chs(sector, &head, &track, §or);
LOG("head: %d \ttrack: %d \tsector: %d\n", head, track, sector);
/* turn it on if not */
motor_on();
if (inb_p(FD_DIR) & 0x80) {
changed = TRUE;
seek(1, head); /* clear "disk change" status */
recalibrate();
motor_off();
printk("floppy_rw: Disk change detected. You are going to DIE:)\n");
pause(); /* just put it in DIE */
}
/* move head to the right track */
if (!seek(track, head)) {
motor_off();
printk("floppy_rw: Error seeking to track#%d\n", track);
return FALSE;
}
if ((unsigned long)buf >= 0xff000) {
dma_buffer = tmp_dma_buffer;
if (command == FD_WRITE)
memcpy(dma_buffer, buf, 512);
}
setup_DMA((unsigned long)dma_buffer, command);
send_byte(command);
send_byte(head<<2 | 0);
send_byte(track);
send_byte(head);
send_byte(sector);
send_byte(2); /* sector size = 125 * 2^(2) */
send_byte(floppy.sector);
send_byte(0);
send_byte(0xFF); /* sector size(only two valid vaules, 0xff when n!=0*/
if (!wait_fdc(FALSE)) {
//LOG("wait fdc failed!\n");
//return 0;
/*
printk("Time out, trying operation again after reset() \n");
reset();
return floppy_rw(sector, buf, command);
*/
}
motor_off();
if (/*res != 7 || */(ST0 & 0xf8) || (ST1 & 0xbf) || (ST2 & 0x73) ) {
if (ST1 & 0x02)
LOG("Drive is write protected!\n");
else
LOG("floppy_rw: bad interrupt!\n");
return -EIO;
} else {
LOG("floppy_rw: OK\n");
if ((unsigned long)buf >= 0xff000 && command == FD_READ)
memcpy(buf, dma_buffer, 512);
return 0;
}
}
