/* This function calibrates the datarate (i.e. determines the maximal
* usable data rate) and sets the global variable ft_qic_std to qic_std
*
*/
int ftape_calibrate_data_rate(unsigned int qic_std)
{
int rate = ft_fdc_rate_limit;
int result;
TRACE_FUN(ft_t_flow);
ft_qic_std = qic_std;
if (ft_qic_std == -1) {
TRACE_ABORT(-EIO, ft_t_err,
"Unable to determine data rate if QIC standard is unknown");
}
/* Select highest rate supported by both fdc and drive.
* Start with highest rate supported by the fdc.
*/
while (fdc_set_data_rate(rate) < 0 && rate > 250) {
rate /= 2;
}
TRACE(ft_t_info,
"Highest FDC supported data rate: %d Kbps", rate);
ft_fdc_max_rate = rate;
do {
result = ftape_set_data_rate(rate, ft_qic_std);
} while (result == -EINVAL && (rate /= 2) > 250);
if (result < 0) {
TRACE_ABORT(-EIO, ft_t_err, "set datarate failed");
}
ft_data_rate = rate;
TRACE_EXIT 0;
}
int ftape_init_drive(int *formatted)
{
TRACE_FUN(5, "ftape_init_drive");
int result = 0;
int status;
result = ftape_report_raw_drive_status(&status);
if (result >= 0 && (status & QIC_STATUS_CARTRIDGE_PRESENT)) {
if (!(status & QIC_STATUS_AT_BOT)) {
/* Antique drives will get here after a soft reset,
* modern ones only if the driver is loaded when the
* tape wasn't rewound properly.
*/
ftape_seek_to_bot();
}
if (!(status & QIC_STATUS_REFERENCED)) {
TRACE(5, "starting seek_load_point");
result = ftape_command_wait(QIC_SEEK_LOAD_POINT,
timeout.reset, &status);
if (result < 0) {
TRACE(1, "seek_load_point failed (command)");
}
}
}
if (result >= 0) {
int rate;
*formatted = (status & QIC_STATUS_REFERENCED);
if (!*formatted) {
TRACE(1, "Warning: tape is not formatted !");
}
/* Select highest rate supported by both fdc and drive.
* Start with highest rate supported by the fdc.
*/
if (fdc.type >= i82078_1)
rate = 0;
else if (fdc.type >= i82077)
rate = 1;
else
rate = 2;
do {
result = ftape_set_data_rate(rate);
if (result >= 0) {
ftape_calc_timeouts();
break;
}
++rate;
} while (rate < 4);
if (result < 0) {
result = -EIO;
}
}
if (result >= 0) {
/* Tape should be at bot if new cartridge ! */
ftape_new_cartridge();
}
init_drive_needed = 0;
TRACE_EXIT;
return result;
}
int ftape_half_data_rate(void)
{
if (ft_data_rate < 500) {
return -1;
}
if (ftape_set_data_rate(ft_data_rate / 2, ft_qic_std) < 0) {
return -EIO;
}
ftape_calc_timeouts(ft_qic_std, ft_data_rate, ftape_tape_len);
return 0;
}
