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
14 #include "pic.h" // unmask_pic1
16 #define BX_FLOPPY_ON_CNT 37 /* 2 seconds */
18 // New diskette parameter table adding 3 parameters from IBM
19 // Since no provisions are made for multiple drive types, most
20 // values in this table are ignored. I set parameters for 1.44M
22 struct floppy_ext_dbt_s diskette_param_table2 VISIBLE16 = {
25 .specify2 = 0x02, // head load time 0000001, DMA used
26 .shutoff_ticks = 0x25,
29 .interblock_len = 0x1B,
36 .max_track = 79, // maximum track
37 .data_rate = 0, // data transfer rate
38 .drive_type = 4, // drive type in cmos
44 if (! CONFIG_FLOPPY_SUPPORT)
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);
71 // Enable IRQ6 (handle_0e)
72 unmask_pic1(PIC1_IRQ6);
76 set_diskette_current_cyl(u8 drive, u8 cyl)
79 SET_BDA(floppy_track1, cyl);
81 SET_BDA(floppy_track0, cyl);
85 get_drive_type(u8 drive)
87 // check CMOS to see if drive exists
88 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
97 floppy_media_known(u8 drive)
99 if (!(GET_BDA(floppy_recalibration_status) & (1<<drive)))
101 u8 v = GET_BDA(floppy_media_state[drive]);
102 if (!(v & FMS_MEDIA_DRIVE_ESTABLISHED))
108 floppy_reset_controller()
111 u8 val8 = inb(PORT_FD_DOR);
112 outb(val8 & ~0x04, PORT_FD_DOR);
113 outb(val8 | 0x04, PORT_FD_DOR);
115 // Wait for controller to come out of reset
116 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
121 floppy_prepare_controller(u8 drive)
123 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
125 // turn on motor of selected drive, DMA & int enabled, normal operation
126 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
132 outb(dor, PORT_FD_DOR);
134 // reset the disk motor timeout value of INT 08
135 SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
137 // wait for drive readiness
138 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
141 if (prev_reset == 0) {
145 v = GET_BDA(floppy_recalibration_status);
153 SET_BDA(floppy_recalibration_status, v);
158 floppy_pio(u8 *cmd, u8 cmdlen)
160 floppy_prepare_controller(cmd[1] & 1);
162 // send command to controller
164 for (i=0; i<cmdlen; i++)
165 outb(cmd[i], PORT_FD_DATA);
170 if (!GET_BDA(floppy_motor_counter)) {
172 floppy_reset_controller();
173 return DISK_RET_ETIMEOUT;
175 v = GET_BDA(floppy_recalibration_status);
183 SET_BDA(floppy_recalibration_status, v);
189 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
191 // es:bx = pointer to where to place information from diskette
192 // port 04: DMA-1 base and current address, channel 2
193 // port 05: DMA-1 base and current count, channel 2
194 u16 page = regs->es >> 12; // upper 4 bits
195 u16 base_es = regs->es << 4; // lower 16bits contributed by ES
196 u16 base_address = base_es + regs->bx; // lower 16 bits of address
197 // contributed by ES:BX
198 if (base_address < base_es)
199 // in case of carry, adjust page by 1
202 // check for 64K boundary overrun
203 u16 last_addr = base_address + count;
204 if (last_addr < base_address)
205 return DISK_RET_EBOUNDARY;
207 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
210 mode_register = 0x46;
212 //DEBUGF("floppy dma c2\n");
213 outb(0x06, PORT_DMA1_MASK_REG);
214 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
215 outb(base_address, PORT_DMA_ADDR_2);
216 outb(base_address>>8, PORT_DMA_ADDR_2);
217 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
218 outb(count, PORT_DMA_CNT_2);
219 outb(count>>8, PORT_DMA_CNT_2);
221 // port 0b: DMA-1 Mode Register
222 // transfer type=write, channel 2
223 outb(mode_register, PORT_DMA1_MODE_REG);
225 // port 81: DMA-1 Page Register, channel 2
226 outb(page, PORT_DMA_PAGE_2);
228 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
230 u8 ret = floppy_pio(cmd, cmdlen);
234 // check port 3f4 for accessibility to status bytes
235 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
236 BX_PANIC("int13_diskette: ctrl not ready\n");
238 // read 7 return status bytes from controller
240 for (i=0; i<7; i++) {
241 u8 v = inb(PORT_FD_DATA);
243 SET_BDA(floppy_return_status[i], v);
250 floppy_drive_recal(u8 drive)
252 // send Recalibrate command (2 bytes) to controller
254 data[0] = 0x07; // 07: Recalibrate
255 data[1] = drive; // 0=drive0, 1=drive1
258 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
259 set_diskette_current_cyl(drive, 0);
263 floppy_media_sense(u8 drive)
266 u8 config_data, media_state;
268 floppy_drive_recal(drive);
270 // for now cheat and get drive type from CMOS,
271 // assume media is same as drive type
274 // Bitfields for diskette media control:
275 // Bit(s) Description (Table M0028)
276 // 7-6 last data rate set by controller
277 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
278 // 5-4 last diskette drive step rate selected
279 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
280 // 3-2 {data rate at start of operation}
284 // Bitfields for diskette drive media state:
285 // Bit(s) Description (Table M0030)
287 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
288 // 5 double stepping required (e.g. 360kB in 1.2MB)
289 // 4 media type established
290 // 3 drive capable of supporting 4MB media
291 // 2-0 on exit from BIOS, contains
292 // 000 trying 360kB in 360kB
293 // 001 trying 360kB in 1.2MB
294 // 010 trying 1.2MB in 1.2MB
295 // 011 360kB in 360kB established
296 // 100 360kB in 1.2MB established
297 // 101 1.2MB in 1.2MB established
299 // 111 all other formats/drives
301 switch (get_drive_type(drive)) {
304 config_data = 0x00; // 0000 0000
305 media_state = 0x25; // 0010 0101
309 // 1.2 MB 5.25" drive
310 config_data = 0x00; // 0000 0000
311 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
316 config_data = 0x00; // 0000 0000 ???
317 media_state = 0x17; // 0001 0111
321 // 1.44 MB 3.5" drive
322 config_data = 0x00; // 0000 0000
323 media_state = 0x17; // 0001 0111
327 // 2.88 MB 3.5" drive
328 config_data = 0xCC; // 1100 1100
329 media_state = 0xD7; // 1101 0111
333 // Extended floppy size uses special cmos setting
336 config_data = 0x00; // 0000 0000
337 media_state = 0x27; // 0010 0111
342 config_data = 0x00; // 0000 0000
343 media_state = 0x27; // 0010 0111
348 config_data = 0x00; // 0000 0000
349 media_state = 0x27; // 0010 0111
354 config_data = 0x00; // 0000 0000
355 media_state = 0x00; // 0000 0000
359 SET_BDA(floppy_last_data_rate, config_data);
360 SET_BDA(floppy_media_state[drive], media_state);
364 #define floppy_ret(regs, code) \
365 __floppy_ret(__func__, (regs), (code))
368 __floppy_ret(const char *fname, struct bregs *regs, u8 code)
370 SET_BDA(floppy_last_status, code);
372 __set_code_fail(fname, regs, code);
374 set_code_success(regs);
378 floppy_fail(struct bregs *regs, u8 code)
380 floppy_ret(regs, code);
381 regs->al = 0; // no sectors read
385 check_drive(struct bregs *regs, u8 drive)
387 // see if drive exists
388 if (drive > 1 || !get_drive_type(drive)) {
389 // XXX - return type doesn't match
390 floppy_fail(regs, DISK_RET_ETIMEOUT);
394 // see if media in drive, and type is known
395 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
396 floppy_fail(regs, DISK_RET_EMEDIA);
402 // diskette controller reset
404 floppy_1300(struct bregs *regs, u8 drive)
407 floppy_ret(regs, DISK_RET_EPARAM);
410 if (!get_drive_type(drive)) {
411 floppy_ret(regs, DISK_RET_ETIMEOUT);
414 set_diskette_current_cyl(drive, 0); // current cylinder
415 floppy_ret(regs, DISK_RET_SUCCESS);
418 // Read Diskette Status
420 floppy_1301(struct bregs *regs, u8 drive)
422 u8 v = GET_BDA(floppy_last_status);
427 // Read Diskette Sectors
429 floppy_1302(struct bregs *regs, u8 drive)
431 if (check_drive(regs, drive))
434 u8 num_sectors = regs->al;
436 u8 sector = regs->cl;
439 if (head > 1 || sector == 0 || num_sectors == 0
440 || track > 79 || num_sectors > 72) {
441 floppy_fail(regs, DISK_RET_EPARAM);
445 // send read-normal-data command (9 bytes) to controller
447 data[0] = 0xe6; // e6: read normal data
448 data[1] = (head << 2) | drive; // HD DR1 DR2
452 data[5] = 2; // 512 byte sector size
453 data[6] = sector + num_sectors - 1; // last sector to read on track
454 data[7] = 0; // Gap length
455 data[8] = 0xff; // Gap length
457 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
459 floppy_fail(regs, ret);
463 if (data[0] & 0xc0) {
464 floppy_fail(regs, DISK_RET_ECONTROLLER);
468 // ??? should track be new val from return_status[3] ?
469 set_diskette_current_cyl(drive, track);
470 // AL = number of sectors read (same value as passed)
471 floppy_ret(regs, DISK_RET_SUCCESS);
474 // Write Diskette Sectors
476 floppy_1303(struct bregs *regs, u8 drive)
478 if (check_drive(regs, drive))
481 u8 num_sectors = regs->al;
483 u8 sector = regs->cl;
486 if (head > 1 || sector == 0 || num_sectors == 0
487 || track > 79 || num_sectors > 72) {
488 floppy_fail(regs, DISK_RET_EPARAM);
492 // send write-normal-data command (9 bytes) to controller
494 data[0] = 0xc5; // c5: write normal data
495 data[1] = (head << 2) | drive; // HD DR1 DR2
499 data[5] = 2; // 512 byte sector size
500 data[6] = sector + num_sectors - 1; // last sector to write on track
501 data[7] = 0; // Gap length
502 data[8] = 0xff; // Gap length
504 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
506 floppy_fail(regs, ret);
510 if (data[0] & 0xc0) {
511 if (data[1] & 0x02) {
516 BX_PANIC("int13_diskette_function: read error\n");
519 // ??? should track be new val from return_status[3] ?
520 set_diskette_current_cyl(drive, track);
521 // AL = number of sectors read (same value as passed)
522 floppy_ret(regs, DISK_RET_SUCCESS);
525 // Verify Diskette Sectors
527 floppy_1304(struct bregs *regs, u8 drive)
529 if (check_drive(regs, drive))
532 u8 num_sectors = regs->al;
534 u8 sector = regs->cl;
537 if (head > 1 || sector == 0 || num_sectors == 0
538 || track > 79 || num_sectors > 72) {
539 floppy_fail(regs, DISK_RET_EPARAM);
543 // ??? should track be new val from return_status[3] ?
544 set_diskette_current_cyl(drive, track);
545 // AL = number of sectors verified (same value as passed)
546 floppy_ret(regs, DISK_RET_SUCCESS);
549 // format diskette track
551 floppy_1305(struct bregs *regs, u8 drive)
553 dprintf(3, "floppy f05\n");
555 if (check_drive(regs, drive))
558 u8 num_sectors = regs->al;
561 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
562 floppy_fail(regs, DISK_RET_EPARAM);
566 // send format-track command (6 bytes) to controller
568 data[0] = 0x4d; // 4d: format track
569 data[1] = (head << 2) | drive; // HD DR1 DR2
570 data[2] = 2; // 512 byte sector size
571 data[3] = num_sectors; // number of sectors per track
572 data[4] = 0; // Gap length
573 data[5] = 0xf6; // Fill byte
575 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
577 floppy_fail(regs, ret);
581 if (data[0] & 0xc0) {
582 if (data[1] & 0x02) {
587 BX_PANIC("int13_diskette_function: read error\n");
590 set_diskette_current_cyl(drive, 0);
594 // read diskette drive parameters
596 floppy_1308(struct bregs *regs, u8 drive)
598 dprintf(3, "floppy f08\n");
600 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
602 if (drive_type & 0xf0)
604 if (drive_type & 0x0f)
614 regs->dl = num_floppies;
625 regs->bl = drive_type;
628 regs->dl = num_floppies;
630 switch (drive_type) {
633 regs->dh = 0; // max head #
636 case 1: // 360KB, 5.25"
637 regs->cx = 0x2709; // 40 tracks, 9 sectors
638 regs->dh = 1; // max head #
641 case 2: // 1.2MB, 5.25"
642 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
643 regs->dh = 1; // max head #
646 case 3: // 720KB, 3.5"
647 regs->cx = 0x4f09; // 80 tracks, 9 sectors
648 regs->dh = 1; // max head #
651 case 4: // 1.44MB, 3.5"
652 regs->cx = 0x4f12; // 80 tracks, 18 sectors
653 regs->dh = 1; // max head #
656 case 5: // 2.88MB, 3.5"
657 regs->cx = 0x4f24; // 80 tracks, 36 sectors
658 regs->dh = 1; // max head #
661 case 6: // 160k, 5.25"
662 regs->cx = 0x2708; // 40 tracks, 8 sectors
663 regs->dh = 0; // max head #
666 case 7: // 180k, 5.25"
667 regs->cx = 0x2709; // 40 tracks, 9 sectors
668 regs->dh = 0; // max head #
671 case 8: // 320k, 5.25"
672 regs->cx = 0x2708; // 40 tracks, 8 sectors
673 regs->dh = 1; // max head #
677 BX_PANIC("floppy: int13: bad floppy type\n");
680 /* set es & di to point to 11 byte diskette param table in ROM */
682 regs->di = (u32)&diskette_param_table2;
683 /* disk status not changed upon success */
686 // read diskette drive type
688 floppy_1315(struct bregs *regs, u8 drive)
690 dprintf(6, "floppy f15\n");
693 regs->ah = 0; // only 2 drives supported
694 // set_diskette_ret_status here ???
697 u8 drive_type = get_drive_type(drive);
699 regs->ah = (drive_type != 0);
703 // get diskette change line status
705 floppy_1316(struct bregs *regs, u8 drive)
708 floppy_ret(regs, DISK_RET_EPARAM);
711 floppy_ret(regs, DISK_RET_ECHANGED);
715 floppy_13XX(struct bregs *regs, u8 drive)
717 floppy_ret(regs, DISK_RET_EPARAM);
721 floppy_13(struct bregs *regs, u8 drive)
723 if (! CONFIG_FLOPPY_SUPPORT) {
726 case 0x01: floppy_1301(regs, drive); break;
727 default: floppy_13XX(regs, drive); break;
732 case 0x00: floppy_1300(regs, drive); break;
733 case 0x01: floppy_1301(regs, drive); break;
734 case 0x02: floppy_1302(regs, drive); break;
735 case 0x03: floppy_1303(regs, drive); break;
736 case 0x04: floppy_1304(regs, drive); break;
737 case 0x05: floppy_1305(regs, drive); break;
738 case 0x08: floppy_1308(regs, drive); break;
739 case 0x15: floppy_1315(regs, drive); break;
740 case 0x16: floppy_1316(regs, drive); break;
741 default: floppy_13XX(regs, drive); break;
745 // INT 0Eh Diskette Hardware ISR Entry Point
749 debug_isr(DEBUG_ISR_0e);
750 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
751 outb(0x08, PORT_FD_DATA); // sense interrupt status
752 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
756 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
759 // diskette interrupt has occurred
760 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
763 // Called from int08 handler.
767 // time to turn off drive(s)?
768 u8 fcount = GET_BDA(floppy_motor_counter);
771 SET_BDA(floppy_motor_counter, fcount);
774 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);