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 BX_FLOPPY_ON_CNT 37 /* 2 seconds */
18 // Since no provisions are made for multiple drive types, most
19 // values in this table are ignored. I set parameters for 1.44M
21 char diskette_param_table[11] = {
23 0x02, // head load time 0000001, DMA used
35 // New diskette parameter table adding 3 parameters from IBM
36 // Since no provisions are made for multiple drive types, most
37 // values in this table are ignored. I set parameters for 1.44M
39 char diskette_param_table2[14] VISIBLE = {
41 0x02, // head load time 0000001, DMA used
52 0, // data transfer rate
53 4, // drive type in cmos
57 // Return codes vary greatly - AL not cleared consistenlty, BDA return
58 // status not set consistently, sometimes panics.
59 // Extra outb(0x000a, 0x02) in read?
60 // Does not disable interrupts on failure paths.
61 // numfloppies used before set in int_1308
62 // int_1305 verifies track but doesn't use it?
65 set_diskette_current_cyl(u8 drive, u8 cyl)
68 SET_BDA(floppy_track1, cyl);
70 SET_BDA(floppy_track0, cyl);
74 get_drive_type(u8 drive)
76 // check CMOS to see if drive exists
77 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
86 floppy_media_known(u8 drive)
88 if (!(GET_BDA(floppy_recalibration_status) & (1<<drive)))
90 u8 v = GET_BDA(floppy_media_state[drive]);
91 if (!(v & FMS_MEDIA_DRIVE_ESTABLISHED))
97 floppy_reset_controller()
100 u8 val8 = inb(PORT_FD_DOR);
101 outb(val8 & ~0x04, PORT_FD_DOR);
102 outb(val8 | 0x04, PORT_FD_DOR);
104 // Wait for controller to come out of reset
105 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
110 floppy_prepare_controller(u8 drive)
112 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
114 // turn on motor of selected drive, DMA & int enabled, normal operation
115 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
121 outb(dor, PORT_FD_DOR);
123 // reset the disk motor timeout value of INT 08
124 SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
126 // wait for drive readiness
127 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
130 if (prev_reset == 0) {
134 v = GET_BDA(floppy_recalibration_status);
135 } while ((v & FRS_TIMEOUT) == 0);
139 SET_BDA(floppy_recalibration_status, v);
144 floppy_pio(u8 *cmd, u8 cmdlen)
146 floppy_prepare_controller(cmd[1] & 1);
148 // send command to controller
150 for (i=0; i<cmdlen; i++)
151 outb(cmd[i], PORT_FD_DATA);
156 if (!GET_BDA(floppy_motor_counter)) {
158 floppy_reset_controller();
159 return DISK_RET_ETIMEOUT;
161 v = GET_BDA(floppy_recalibration_status);
162 } while (!(v & FRS_TIMEOUT));
166 SET_BDA(floppy_recalibration_status, v);
168 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
169 BX_PANIC("int13_diskette: ctrl not ready\n");
175 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
177 // es:bx = pointer to where to place information from diskette
178 // port 04: DMA-1 base and current address, channel 2
179 // port 05: DMA-1 base and current count, channel 2
180 u16 page = regs->es >> 12; // upper 4 bits
181 u16 base_es = regs->es << 4; // lower 16bits contributed by ES
182 u16 base_address = base_es + regs->bx; // lower 16 bits of address
183 // contributed by ES:BX
184 if (base_address < base_es)
185 // in case of carry, adjust page by 1
188 // check for 64K boundary overrun
189 u16 last_addr = base_address + count;
190 if (last_addr < base_address)
191 return DISK_RET_EBOUNDARY;
193 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
196 mode_register = 0x46;
198 DEBUGF("floppy dma c2");
199 outb(0x06, PORT_DMA1_MASK_REG);
200 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
201 outb(base_address, PORT_DMA_ADDR_2);
202 outb(base_address>>8, PORT_DMA_ADDR_2);
203 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
204 outb(count, PORT_DMA_CNT_2);
205 outb(count>>8, PORT_DMA_CNT_2);
207 // port 0b: DMA-1 Mode Register
208 // transfer type=write, channel 2
209 outb(mode_register, PORT_DMA1_MODE_REG);
211 // port 81: DMA-1 Page Register, channel 2
212 outb(page, PORT_DMA_PAGE_2);
214 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
216 u8 ret = floppy_pio(cmd, cmdlen);
220 // read 7 return status bytes from controller
222 for (i=0; i<7; i++) {
223 u8 v = inb(PORT_FD_DATA);
225 SET_BDA(floppy_return_status[i], v);
232 floppy_drive_recal(u8 drive)
234 // send Recalibrate command (2 bytes) to controller
236 data[0] = 0x07; // 07: Recalibrate
237 data[1] = drive; // 0=drive0, 1=drive1
240 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
241 set_diskette_current_cyl(drive, 0);
245 floppy_media_sense(u8 drive)
248 u8 config_data, media_state;
250 floppy_drive_recal(drive);
252 // for now cheat and get drive type from CMOS,
253 // assume media is same as drive type
256 // Bitfields for diskette media control:
257 // Bit(s) Description (Table M0028)
258 // 7-6 last data rate set by controller
259 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
260 // 5-4 last diskette drive step rate selected
261 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
262 // 3-2 {data rate at start of operation}
266 // Bitfields for diskette drive media state:
267 // Bit(s) Description (Table M0030)
269 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
270 // 5 double stepping required (e.g. 360kB in 1.2MB)
271 // 4 media type established
272 // 3 drive capable of supporting 4MB media
273 // 2-0 on exit from BIOS, contains
274 // 000 trying 360kB in 360kB
275 // 001 trying 360kB in 1.2MB
276 // 010 trying 1.2MB in 1.2MB
277 // 011 360kB in 360kB established
278 // 100 360kB in 1.2MB established
279 // 101 1.2MB in 1.2MB established
281 // 111 all other formats/drives
283 switch (get_drive_type(drive)) {
286 config_data = 0x00; // 0000 0000
287 media_state = 0x25; // 0010 0101
291 // 1.2 MB 5.25" drive
292 config_data = 0x00; // 0000 0000
293 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
298 config_data = 0x00; // 0000 0000 ???
299 media_state = 0x17; // 0001 0111
303 // 1.44 MB 3.5" drive
304 config_data = 0x00; // 0000 0000
305 media_state = 0x17; // 0001 0111
309 // 2.88 MB 3.5" drive
310 config_data = 0xCC; // 1100 1100
311 media_state = 0xD7; // 1101 0111
315 // Extended floppy size uses special cmos setting
318 config_data = 0x00; // 0000 0000
319 media_state = 0x27; // 0010 0111
324 config_data = 0x00; // 0000 0000
325 media_state = 0x27; // 0010 0111
330 config_data = 0x00; // 0000 0000
331 media_state = 0x27; // 0010 0111
336 config_data = 0x00; // 0000 0000
337 media_state = 0x00; // 0000 0000
341 SET_BDA(floppy_last_data_rate, config_data);
342 SET_BDA(floppy_media_state[drive], media_state);
347 floppy_ret(struct bregs *regs, u8 code)
350 SET_BDA(floppy_last_status, code);
355 floppy_fail(struct bregs *regs, u8 code)
357 regs->al = 0; // no sectors read
358 floppy_ret(regs, code);
362 check_drive(struct bregs *regs, u8 drive)
364 // see if drive exists
365 if (drive > 1 || !get_drive_type(drive)) {
366 floppy_fail(regs, DISK_RET_ETIMEOUT);
370 // see if media in drive, and type is known
371 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
372 floppy_fail(regs, DISK_RET_EMEDIA);
378 // diskette controller reset
380 floppy_1300(struct bregs *regs, u8 drive)
383 floppy_ret(regs, DISK_RET_EPARAM);
386 if (!get_drive_type(drive)) {
387 floppy_ret(regs, DISK_RET_ETIMEOUT);
390 set_diskette_current_cyl(drive, 0); // current cylinder
391 floppy_ret(regs, DISK_RET_SUCCESS);
394 // Read Diskette Status
396 floppy_1301(struct bregs *regs, u8 drive)
398 u8 v = GET_BDA(floppy_last_status);
403 // Read Diskette Sectors
405 floppy_1302(struct bregs *regs, u8 drive)
407 if (check_drive(regs, drive))
410 u8 num_sectors = regs->al;
412 u8 sector = regs->cl;
415 if (head > 1 || sector == 0 || num_sectors == 0
416 || track > 79 || num_sectors > 72) {
417 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
418 floppy_fail(regs, DISK_RET_EPARAM);
422 // send read-normal-data command (9 bytes) to controller
424 data[0] = 0xe6; // e6: read normal data
425 data[1] = (head << 2) | drive; // HD DR1 DR2
429 data[5] = 2; // 512 byte sector size
430 data[6] = sector + num_sectors - 1; // last sector to read on track
431 data[7] = 0; // Gap length
432 data[8] = 0xff; // Gap length
434 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
436 floppy_fail(regs, ret);
440 if (data[0] & 0xc0) {
441 floppy_fail(regs, DISK_RET_ECONTROLLER);
445 // ??? should track be new val from return_status[3] ?
446 set_diskette_current_cyl(drive, track);
447 // AL = number of sectors read (same value as passed)
448 floppy_ret(regs, DISK_RET_SUCCESS);
451 // Write Diskette Sectors
453 floppy_1303(struct bregs *regs, u8 drive)
455 if (check_drive(regs, drive))
458 u8 num_sectors = regs->al;
460 u8 sector = regs->cl;
463 if (head > 1 || sector == 0 || num_sectors == 0
464 || track > 79 || num_sectors > 72) {
465 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
466 floppy_fail(regs, DISK_RET_EPARAM);
470 // send write-normal-data command (9 bytes) to controller
472 data[0] = 0xc5; // c5: write normal data
473 data[1] = (head << 2) | drive; // HD DR1 DR2
477 data[5] = 2; // 512 byte sector size
478 data[6] = sector + num_sectors - 1; // last sector to write on track
479 data[7] = 0; // Gap length
480 data[8] = 0xff; // Gap length
482 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
484 floppy_fail(regs, ret);
488 if (data[0] & 0xc0) {
489 if (data[1] & 0x02) {
494 BX_PANIC("int13_diskette_function: read error\n");
497 // ??? should track be new val from return_status[3] ?
498 set_diskette_current_cyl(drive, track);
499 // AL = number of sectors read (same value as passed)
500 floppy_ret(regs, DISK_RET_SUCCESS);
503 // Verify Diskette Sectors
505 floppy_1304(struct bregs *regs, u8 drive)
507 if (check_drive(regs, drive))
510 u8 num_sectors = regs->al;
512 u8 sector = regs->cl;
515 if (head > 1 || sector == 0 || num_sectors == 0
516 || track > 79 || num_sectors > 72) {
517 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
518 floppy_fail(regs, DISK_RET_EPARAM);
522 // ??? should track be new val from return_status[3] ?
523 set_diskette_current_cyl(drive, track);
524 // AL = number of sectors verified (same value as passed)
525 floppy_ret(regs, DISK_RET_SUCCESS);
528 // format diskette track
530 floppy_1305(struct bregs *regs, u8 drive)
532 DEBUGF("floppy f05\n");
534 if (check_drive(regs, drive))
537 u8 num_sectors = regs->al;
540 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
541 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
542 floppy_fail(regs, DISK_RET_EPARAM);
546 // send format-track command (6 bytes) to controller
548 data[0] = 0x4d; // 4d: format track
549 data[1] = (head << 2) | drive; // HD DR1 DR2
550 data[2] = 2; // 512 byte sector size
551 data[3] = num_sectors; // number of sectors per track
552 data[4] = 0; // Gap length
553 data[5] = 0xf6; // Fill byte
555 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
557 floppy_fail(regs, ret);
561 if (data[0] & 0xc0) {
562 if (data[1] & 0x02) {
567 BX_PANIC("int13_diskette_function: read error\n");
570 set_diskette_current_cyl(drive, 0);
574 // read diskette drive parameters
576 floppy_1308(struct bregs *regs, u8 drive)
578 DEBUGF("floppy f08\n");
580 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
582 if (drive_type & 0xf0)
584 if (drive_type & 0x0f)
594 regs->dl = num_floppies;
605 regs->bl = drive_type;
608 regs->dl = num_floppies;
610 switch (drive_type) {
613 regs->dh = 0; // max head #
616 case 1: // 360KB, 5.25"
617 regs->cx = 0x2709; // 40 tracks, 9 sectors
618 regs->dh = 1; // max head #
621 case 2: // 1.2MB, 5.25"
622 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
623 regs->dh = 1; // max head #
626 case 3: // 720KB, 3.5"
627 regs->cx = 0x4f09; // 80 tracks, 9 sectors
628 regs->dh = 1; // max head #
631 case 4: // 1.44MB, 3.5"
632 regs->cx = 0x4f12; // 80 tracks, 18 sectors
633 regs->dh = 1; // max head #
636 case 5: // 2.88MB, 3.5"
637 regs->cx = 0x4f24; // 80 tracks, 36 sectors
638 regs->dh = 1; // max head #
641 case 6: // 160k, 5.25"
642 regs->cx = 0x2708; // 40 tracks, 8 sectors
643 regs->dh = 0; // max head #
646 case 7: // 180k, 5.25"
647 regs->cx = 0x2709; // 40 tracks, 9 sectors
648 regs->dh = 0; // max head #
651 case 8: // 320k, 5.25"
652 regs->cx = 0x2708; // 40 tracks, 8 sectors
653 regs->dh = 1; // max head #
657 BX_PANIC("floppy: int13: bad floppy type\n");
660 /* set es & di to point to 11 byte diskette param table in ROM */
662 regs->di = (u16)diskette_param_table2;
663 /* disk status not changed upon success */
666 // read diskette drive type
668 floppy_1315(struct bregs *regs, u8 drive)
670 DEBUGF("floppy f15\n");
672 regs->ah = 0; // only 2 drives supported
673 // set_diskette_ret_status here ???
677 u8 drive_type = get_drive_type(drive);
679 regs->ah = (drive_type != 0);
683 // get diskette change line status
685 floppy_1316(struct bregs *regs, u8 drive)
687 DEBUGF("floppy f16\n");
689 floppy_ret(regs, DISK_RET_EPARAM);
692 floppy_ret(regs, DISK_RET_ECHANGED);
696 floppy_13XX(struct bregs *regs, u8 drive)
698 BX_INFO("int13_diskette: unsupported AH=%02x\n", GET_AH());
699 floppy_ret(regs, DISK_RET_EPARAM);
703 floppy_13(struct bregs *regs, u8 drive)
705 if (CONFIG_FLOPPY_SUPPORT) {
707 case 0x00: floppy_1300(regs, drive); break;
708 case 0x01: floppy_1301(regs, drive); break;
709 case 0x02: floppy_1302(regs, drive); break;
710 case 0x03: floppy_1303(regs, drive); break;
711 case 0x04: floppy_1304(regs, drive); break;
712 case 0x05: floppy_1305(regs, drive); break;
713 case 0x08: floppy_1308(regs, drive); break;
714 case 0x15: floppy_1315(regs, drive); break;
715 case 0x16: floppy_1316(regs, drive); break;
716 default: floppy_13XX(regs, drive); break;
720 case 0x01: floppy_1301(regs, drive); break;
721 default: floppy_13XX(regs, drive); break;
726 // INT 0Eh Diskette Hardware ISR Entry Point
728 handle_0e(struct bregs *regs)
731 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
732 outb(0x08, PORT_FD_DATA); // sense interrupt status
733 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
737 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
740 // diskette interrupt has occurred
741 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
744 // Called from int08 handler.
748 // time to turn off drive(s)?
749 u8 fcount = GET_BDA(floppy_motor_counter);
752 SET_BDA(floppy_motor_counter, fcount);
755 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);