1 // 16bit code to access floppy drives.
3 // Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
4 // Copyright (C) 2002 MandrakeSoft S.A.
6 // This file may be distributed under the terms of the GNU GPLv3 license.
8 #include "types.h" // u8
9 #include "disk.h" // DISK_RET_SUCCESS
10 #include "config.h" // CONFIG_FLOPPY_SUPPORT
11 #include "biosvar.h" // struct bregs
12 #include "util.h" // irq_disable
13 #include "cmos.h" // inb_cmos
15 #define DEBUGF1(fmt, args...) bprintf(0, fmt , ##args)
16 #define DEBUGF(fmt, args...)
18 #define BX_FLOPPY_ON_CNT 37 /* 2 seconds */
20 // New diskette parameter table adding 3 parameters from IBM
21 // Since no provisions are made for multiple drive types, most
22 // values in this table are ignored. I set parameters for 1.44M
24 struct floppy_ext_dbt_s diskette_param_table2 VISIBLE16 = {
27 .specify2 = 0x02, // head load time 0000001, DMA used
28 .shutoff_ticks = 0x25,
31 .interblock_len = 0x1B,
38 .max_track = 79, // maximum track
39 .data_rate = 0, // data transfer rate
40 .drive_type = 4, // drive type in cmos
46 dprintf(3, "init floppy drives\n");
47 u8 type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
59 SET_BDA(floppy_harddisk_info, out);
61 // Update equipment word bits for floppy
62 if (num_floppies == 1)
63 // 1 drive, ready for boot
64 SETBITS_BDA(equipment_list_flags, 0x01);
65 else if (num_floppies == 2)
66 // 2 drives, ready for boot
67 SETBITS_BDA(equipment_list_flags, 0x41);
69 outb(0x02, PORT_DMA1_MASK_REG);
73 set_diskette_current_cyl(u8 drive, u8 cyl)
76 SET_BDA(floppy_track1, cyl);
78 SET_BDA(floppy_track0, cyl);
82 get_drive_type(u8 drive)
84 // check CMOS to see if drive exists
85 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
94 floppy_media_known(u8 drive)
96 if (!(GET_BDA(floppy_recalibration_status) & (1<<drive)))
98 u8 v = GET_BDA(floppy_media_state[drive]);
99 if (!(v & FMS_MEDIA_DRIVE_ESTABLISHED))
105 floppy_reset_controller()
108 u8 val8 = inb(PORT_FD_DOR);
109 outb(val8 & ~0x04, PORT_FD_DOR);
110 outb(val8 | 0x04, PORT_FD_DOR);
112 // Wait for controller to come out of reset
113 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
118 floppy_prepare_controller(u8 drive)
120 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
122 // turn on motor of selected drive, DMA & int enabled, normal operation
123 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
129 outb(dor, PORT_FD_DOR);
131 // reset the disk motor timeout value of INT 08
132 SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
134 // wait for drive readiness
135 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
138 if (prev_reset == 0) {
142 v = GET_BDA(floppy_recalibration_status);
150 SET_BDA(floppy_recalibration_status, v);
155 floppy_pio(u8 *cmd, u8 cmdlen)
157 floppy_prepare_controller(cmd[1] & 1);
159 // send command to controller
161 for (i=0; i<cmdlen; i++)
162 outb(cmd[i], PORT_FD_DATA);
167 if (!GET_BDA(floppy_motor_counter)) {
169 floppy_reset_controller();
170 return DISK_RET_ETIMEOUT;
172 v = GET_BDA(floppy_recalibration_status);
180 SET_BDA(floppy_recalibration_status, v);
186 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
188 // es:bx = pointer to where to place information from diskette
189 // port 04: DMA-1 base and current address, channel 2
190 // port 05: DMA-1 base and current count, channel 2
191 u16 page = regs->es >> 12; // upper 4 bits
192 u16 base_es = regs->es << 4; // lower 16bits contributed by ES
193 u16 base_address = base_es + regs->bx; // lower 16 bits of address
194 // contributed by ES:BX
195 if (base_address < base_es)
196 // in case of carry, adjust page by 1
199 // check for 64K boundary overrun
200 u16 last_addr = base_address + count;
201 if (last_addr < base_address)
202 return DISK_RET_EBOUNDARY;
204 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
207 mode_register = 0x46;
209 //DEBUGF("floppy dma c2\n");
210 outb(0x06, PORT_DMA1_MASK_REG);
211 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
212 outb(base_address, PORT_DMA_ADDR_2);
213 outb(base_address>>8, PORT_DMA_ADDR_2);
214 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
215 outb(count, PORT_DMA_CNT_2);
216 outb(count>>8, PORT_DMA_CNT_2);
218 // port 0b: DMA-1 Mode Register
219 // transfer type=write, channel 2
220 outb(mode_register, PORT_DMA1_MODE_REG);
222 // port 81: DMA-1 Page Register, channel 2
223 outb(page, PORT_DMA_PAGE_2);
225 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
227 u8 ret = floppy_pio(cmd, cmdlen);
231 // check port 3f4 for accessibility to status bytes
232 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
233 BX_PANIC("int13_diskette: ctrl not ready\n");
235 // read 7 return status bytes from controller
237 for (i=0; i<7; i++) {
238 u8 v = inb(PORT_FD_DATA);
240 SET_BDA(floppy_return_status[i], v);
247 floppy_drive_recal(u8 drive)
249 // send Recalibrate command (2 bytes) to controller
251 data[0] = 0x07; // 07: Recalibrate
252 data[1] = drive; // 0=drive0, 1=drive1
255 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
256 set_diskette_current_cyl(drive, 0);
260 floppy_media_sense(u8 drive)
263 u8 config_data, media_state;
265 floppy_drive_recal(drive);
267 // for now cheat and get drive type from CMOS,
268 // assume media is same as drive type
271 // Bitfields for diskette media control:
272 // Bit(s) Description (Table M0028)
273 // 7-6 last data rate set by controller
274 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
275 // 5-4 last diskette drive step rate selected
276 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
277 // 3-2 {data rate at start of operation}
281 // Bitfields for diskette drive media state:
282 // Bit(s) Description (Table M0030)
284 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
285 // 5 double stepping required (e.g. 360kB in 1.2MB)
286 // 4 media type established
287 // 3 drive capable of supporting 4MB media
288 // 2-0 on exit from BIOS, contains
289 // 000 trying 360kB in 360kB
290 // 001 trying 360kB in 1.2MB
291 // 010 trying 1.2MB in 1.2MB
292 // 011 360kB in 360kB established
293 // 100 360kB in 1.2MB established
294 // 101 1.2MB in 1.2MB established
296 // 111 all other formats/drives
298 switch (get_drive_type(drive)) {
301 config_data = 0x00; // 0000 0000
302 media_state = 0x25; // 0010 0101
306 // 1.2 MB 5.25" drive
307 config_data = 0x00; // 0000 0000
308 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
313 config_data = 0x00; // 0000 0000 ???
314 media_state = 0x17; // 0001 0111
318 // 1.44 MB 3.5" drive
319 config_data = 0x00; // 0000 0000
320 media_state = 0x17; // 0001 0111
324 // 2.88 MB 3.5" drive
325 config_data = 0xCC; // 1100 1100
326 media_state = 0xD7; // 1101 0111
330 // Extended floppy size uses special cmos setting
333 config_data = 0x00; // 0000 0000
334 media_state = 0x27; // 0010 0111
339 config_data = 0x00; // 0000 0000
340 media_state = 0x27; // 0010 0111
345 config_data = 0x00; // 0000 0000
346 media_state = 0x27; // 0010 0111
351 config_data = 0x00; // 0000 0000
352 media_state = 0x00; // 0000 0000
356 SET_BDA(floppy_last_data_rate, config_data);
357 SET_BDA(floppy_media_state[drive], media_state);
361 #define floppy_ret(regs, code) \
362 __floppy_ret(__func__, (regs), (code))
365 __floppy_ret(const char *fname, struct bregs *regs, u8 code)
367 SET_BDA(floppy_last_status, code);
369 __set_code_fail(fname, regs, code);
371 set_code_success(regs);
375 floppy_fail(struct bregs *regs, u8 code)
377 floppy_ret(regs, code);
378 regs->al = 0; // no sectors read
382 check_drive(struct bregs *regs, u8 drive)
384 // see if drive exists
385 if (drive > 1 || !get_drive_type(drive)) {
386 // XXX - return type doesn't match
387 floppy_fail(regs, DISK_RET_ETIMEOUT);
391 // see if media in drive, and type is known
392 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
393 floppy_fail(regs, DISK_RET_EMEDIA);
399 // diskette controller reset
401 floppy_1300(struct bregs *regs, u8 drive)
404 floppy_ret(regs, DISK_RET_EPARAM);
407 if (!get_drive_type(drive)) {
408 floppy_ret(regs, DISK_RET_ETIMEOUT);
411 set_diskette_current_cyl(drive, 0); // current cylinder
412 floppy_ret(regs, DISK_RET_SUCCESS);
415 // Read Diskette Status
417 floppy_1301(struct bregs *regs, u8 drive)
419 u8 v = GET_BDA(floppy_last_status);
424 // Read Diskette Sectors
426 floppy_1302(struct bregs *regs, u8 drive)
428 if (check_drive(regs, drive))
431 u8 num_sectors = regs->al;
433 u8 sector = regs->cl;
436 if (head > 1 || sector == 0 || num_sectors == 0
437 || track > 79 || num_sectors > 72) {
438 floppy_fail(regs, DISK_RET_EPARAM);
442 // send read-normal-data command (9 bytes) to controller
444 data[0] = 0xe6; // e6: read normal data
445 data[1] = (head << 2) | drive; // HD DR1 DR2
449 data[5] = 2; // 512 byte sector size
450 data[6] = sector + num_sectors - 1; // last sector to read on track
451 data[7] = 0; // Gap length
452 data[8] = 0xff; // Gap length
454 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
456 floppy_fail(regs, ret);
460 if (data[0] & 0xc0) {
461 floppy_fail(regs, DISK_RET_ECONTROLLER);
465 // ??? should track be new val from return_status[3] ?
466 set_diskette_current_cyl(drive, track);
467 // AL = number of sectors read (same value as passed)
468 floppy_ret(regs, DISK_RET_SUCCESS);
471 // Write Diskette Sectors
473 floppy_1303(struct bregs *regs, u8 drive)
475 if (check_drive(regs, drive))
478 u8 num_sectors = regs->al;
480 u8 sector = regs->cl;
483 if (head > 1 || sector == 0 || num_sectors == 0
484 || track > 79 || num_sectors > 72) {
485 floppy_fail(regs, DISK_RET_EPARAM);
489 // send write-normal-data command (9 bytes) to controller
491 data[0] = 0xc5; // c5: write normal data
492 data[1] = (head << 2) | drive; // HD DR1 DR2
496 data[5] = 2; // 512 byte sector size
497 data[6] = sector + num_sectors - 1; // last sector to write on track
498 data[7] = 0; // Gap length
499 data[8] = 0xff; // Gap length
501 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
503 floppy_fail(regs, ret);
507 if (data[0] & 0xc0) {
508 if (data[1] & 0x02) {
513 BX_PANIC("int13_diskette_function: read error\n");
516 // ??? should track be new val from return_status[3] ?
517 set_diskette_current_cyl(drive, track);
518 // AL = number of sectors read (same value as passed)
519 floppy_ret(regs, DISK_RET_SUCCESS);
522 // Verify Diskette Sectors
524 floppy_1304(struct bregs *regs, u8 drive)
526 if (check_drive(regs, drive))
529 u8 num_sectors = regs->al;
531 u8 sector = regs->cl;
534 if (head > 1 || sector == 0 || num_sectors == 0
535 || track > 79 || num_sectors > 72) {
536 floppy_fail(regs, DISK_RET_EPARAM);
540 // ??? should track be new val from return_status[3] ?
541 set_diskette_current_cyl(drive, track);
542 // AL = number of sectors verified (same value as passed)
543 floppy_ret(regs, DISK_RET_SUCCESS);
546 // format diskette track
548 floppy_1305(struct bregs *regs, u8 drive)
550 DEBUGF("floppy f05\n");
552 if (check_drive(regs, drive))
555 u8 num_sectors = regs->al;
558 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
559 floppy_fail(regs, DISK_RET_EPARAM);
563 // send format-track command (6 bytes) to controller
565 data[0] = 0x4d; // 4d: format track
566 data[1] = (head << 2) | drive; // HD DR1 DR2
567 data[2] = 2; // 512 byte sector size
568 data[3] = num_sectors; // number of sectors per track
569 data[4] = 0; // Gap length
570 data[5] = 0xf6; // Fill byte
572 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
574 floppy_fail(regs, ret);
578 if (data[0] & 0xc0) {
579 if (data[1] & 0x02) {
584 BX_PANIC("int13_diskette_function: read error\n");
587 set_diskette_current_cyl(drive, 0);
591 // read diskette drive parameters
593 floppy_1308(struct bregs *regs, u8 drive)
595 DEBUGF("floppy f08\n");
597 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
599 if (drive_type & 0xf0)
601 if (drive_type & 0x0f)
611 regs->dl = num_floppies;
622 regs->bl = drive_type;
625 regs->dl = num_floppies;
627 switch (drive_type) {
630 regs->dh = 0; // max head #
633 case 1: // 360KB, 5.25"
634 regs->cx = 0x2709; // 40 tracks, 9 sectors
635 regs->dh = 1; // max head #
638 case 2: // 1.2MB, 5.25"
639 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
640 regs->dh = 1; // max head #
643 case 3: // 720KB, 3.5"
644 regs->cx = 0x4f09; // 80 tracks, 9 sectors
645 regs->dh = 1; // max head #
648 case 4: // 1.44MB, 3.5"
649 regs->cx = 0x4f12; // 80 tracks, 18 sectors
650 regs->dh = 1; // max head #
653 case 5: // 2.88MB, 3.5"
654 regs->cx = 0x4f24; // 80 tracks, 36 sectors
655 regs->dh = 1; // max head #
658 case 6: // 160k, 5.25"
659 regs->cx = 0x2708; // 40 tracks, 8 sectors
660 regs->dh = 0; // max head #
663 case 7: // 180k, 5.25"
664 regs->cx = 0x2709; // 40 tracks, 9 sectors
665 regs->dh = 0; // max head #
668 case 8: // 320k, 5.25"
669 regs->cx = 0x2708; // 40 tracks, 8 sectors
670 regs->dh = 1; // max head #
674 BX_PANIC("floppy: int13: bad floppy type\n");
677 /* set es & di to point to 11 byte diskette param table in ROM */
679 regs->di = (u32)&diskette_param_table2;
680 /* disk status not changed upon success */
683 // read diskette drive type
685 floppy_1315(struct bregs *regs, u8 drive)
687 DEBUGF("floppy f15\n");
690 regs->ah = 0; // only 2 drives supported
691 // set_diskette_ret_status here ???
694 u8 drive_type = get_drive_type(drive);
696 regs->ah = (drive_type != 0);
700 // get diskette change line status
702 floppy_1316(struct bregs *regs, u8 drive)
704 DEBUGF("floppy f16\n");
706 floppy_ret(regs, DISK_RET_EPARAM);
709 floppy_ret(regs, DISK_RET_ECHANGED);
713 floppy_13XX(struct bregs *regs, u8 drive)
715 floppy_ret(regs, DISK_RET_EPARAM);
719 floppy_13(struct bregs *regs, u8 drive)
721 if (! CONFIG_FLOPPY_SUPPORT) {
724 case 0x01: floppy_1301(regs, drive); break;
725 default: floppy_13XX(regs, drive); break;
730 case 0x00: floppy_1300(regs, drive); break;
731 case 0x01: floppy_1301(regs, drive); break;
732 case 0x02: floppy_1302(regs, drive); break;
733 case 0x03: floppy_1303(regs, drive); break;
734 case 0x04: floppy_1304(regs, drive); break;
735 case 0x05: floppy_1305(regs, drive); break;
736 case 0x08: floppy_1308(regs, drive); break;
737 case 0x15: floppy_1315(regs, drive); break;
738 case 0x16: floppy_1316(regs, drive); break;
739 default: floppy_13XX(regs, drive); break;
743 // INT 0Eh Diskette Hardware ISR Entry Point
747 debug_isr(DEBUG_ISR_0e);
748 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
749 outb(0x08, PORT_FD_DATA); // sense interrupt status
750 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
754 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
757 // diskette interrupt has occurred
758 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
761 // Called from int08 handler.
765 // time to turn off drive(s)?
766 u8 fcount = GET_BDA(floppy_motor_counter);
769 SET_BDA(floppy_motor_counter, fcount);
772 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);