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 */
17 // XXX - //.org 0xefc7
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 char diskette_param_table[11] = {
24 0x02, // head load time 0000001, DMA used
36 // New diskette parameter table adding 3 parameters from IBM
37 // Since no provisions are made for multiple drive types, most
38 // values in this table are ignored. I set parameters for 1.44M
40 char diskette_param_table2[14] VISIBLE = {
42 0x02, // head load time 0000001, DMA used
53 0, // data transfer rate
54 4, // drive type in cmos
58 // Return codes vary greatly - AL not cleared consistenlty, BDA return
59 // status not set consistently, sometimes panics.
60 // Extra outb(0x000a, 0x02) in read?
61 // Does not disable interrupts on failure paths.
62 // numfloppies used before set in int_1308
63 // int_1305 verifies track but doesn't use it?
66 set_diskette_current_cyl(u8 drive, u8 cyl)
69 SET_BDA(floppy_track1, cyl);
71 SET_BDA(floppy_track0, cyl);
75 get_drive_type(u8 drive)
77 // check CMOS to see if drive exists
78 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
87 floppy_media_known(u8 drive)
89 if (!(GET_BDA(floppy_recalibration_status) & (1<<drive)))
91 u8 v = GET_BDA(floppy_media_state[drive]);
92 if (!(v & FMS_MEDIA_DRIVE_ESTABLISHED))
98 floppy_reset_controller()
101 u8 val8 = inb(PORT_FD_DOR);
102 outb(val8 & ~0x04, PORT_FD_DOR);
103 outb(val8 | 0x04, PORT_FD_DOR);
105 // Wait for controller to come out of reset
106 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
111 floppy_prepare_controller(u8 drive)
113 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
115 // turn on motor of selected drive, DMA & int enabled, normal operation
116 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
122 outb(dor, PORT_FD_DOR);
124 // reset the disk motor timeout value of INT 08
125 SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
127 // wait for drive readiness
128 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
131 if (prev_reset == 0) {
135 v = GET_BDA(floppy_recalibration_status);
136 } while ((v & FRS_TIMEOUT) == 0);
140 SET_BDA(floppy_recalibration_status, v);
145 floppy_pio(u8 *cmd, u8 cmdlen)
147 floppy_prepare_controller(cmd[1] & 1);
149 // send command to controller
151 for (i=0; i<cmdlen; i++)
152 outb(cmd[i], PORT_FD_DATA);
157 if (!GET_BDA(floppy_motor_counter)) {
159 floppy_reset_controller();
160 return DISK_RET_ETIMEOUT;
162 v = GET_BDA(floppy_recalibration_status);
163 } while (!(v & FRS_TIMEOUT));
167 SET_BDA(floppy_recalibration_status, v);
169 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
170 BX_PANIC("int13_diskette: ctrl not ready\n");
176 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
178 // es:bx = pointer to where to place information from diskette
179 // port 04: DMA-1 base and current address, channel 2
180 // port 05: DMA-1 base and current count, channel 2
181 u16 page = regs->es >> 12; // upper 4 bits
182 u16 base_es = regs->es << 4; // lower 16bits contributed by ES
183 u16 base_address = base_es + regs->bx; // lower 16 bits of address
184 // contributed by ES:BX
185 if (base_address < base_es)
186 // in case of carry, adjust page by 1
189 // check for 64K boundary overrun
190 u16 last_addr = base_address + count;
191 if (last_addr < base_address)
192 return DISK_RET_EBOUNDARY;
194 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
197 mode_register = 0x46;
199 DEBUGF("floppy dma c2");
200 outb(0x06, PORT_DMA1_MASK_REG);
201 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
202 outb(base_address, PORT_DMA_ADDR_2);
203 outb(base_address>>8, PORT_DMA_ADDR_2);
204 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
205 outb(count, PORT_DMA_CNT_2);
206 outb(count>>8, PORT_DMA_CNT_2);
208 // port 0b: DMA-1 Mode Register
209 // transfer type=write, channel 2
210 outb(mode_register, PORT_DMA1_MODE_REG);
212 // port 81: DMA-1 Page Register, channel 2
213 outb(page, PORT_DMA_PAGE_2);
215 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
217 u8 ret = floppy_pio(cmd, cmdlen);
221 // read 7 return status bytes from controller
223 for (i=0; i<7; i++) {
224 u8 v = inb(PORT_FD_DATA);
226 SET_BDA(floppy_return_status[i], v);
233 floppy_drive_recal(u8 drive)
235 // send Recalibrate command (2 bytes) to controller
237 data[0] = 0x07; // 07: Recalibrate
238 data[1] = drive; // 0=drive0, 1=drive1
241 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
242 set_diskette_current_cyl(drive, 0);
246 floppy_media_sense(u8 drive)
249 u8 config_data, media_state;
251 floppy_drive_recal(drive);
253 // for now cheat and get drive type from CMOS,
254 // assume media is same as drive type
257 // Bitfields for diskette media control:
258 // Bit(s) Description (Table M0028)
259 // 7-6 last data rate set by controller
260 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
261 // 5-4 last diskette drive step rate selected
262 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
263 // 3-2 {data rate at start of operation}
267 // Bitfields for diskette drive media state:
268 // Bit(s) Description (Table M0030)
270 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
271 // 5 double stepping required (e.g. 360kB in 1.2MB)
272 // 4 media type established
273 // 3 drive capable of supporting 4MB media
274 // 2-0 on exit from BIOS, contains
275 // 000 trying 360kB in 360kB
276 // 001 trying 360kB in 1.2MB
277 // 010 trying 1.2MB in 1.2MB
278 // 011 360kB in 360kB established
279 // 100 360kB in 1.2MB established
280 // 101 1.2MB in 1.2MB established
282 // 111 all other formats/drives
284 switch (get_drive_type(drive)) {
287 config_data = 0x00; // 0000 0000
288 media_state = 0x25; // 0010 0101
292 // 1.2 MB 5.25" drive
293 config_data = 0x00; // 0000 0000
294 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
299 config_data = 0x00; // 0000 0000 ???
300 media_state = 0x17; // 0001 0111
304 // 1.44 MB 3.5" drive
305 config_data = 0x00; // 0000 0000
306 media_state = 0x17; // 0001 0111
310 // 2.88 MB 3.5" drive
311 config_data = 0xCC; // 1100 1100
312 media_state = 0xD7; // 1101 0111
316 // Extended floppy size uses special cmos setting
319 config_data = 0x00; // 0000 0000
320 media_state = 0x27; // 0010 0111
325 config_data = 0x00; // 0000 0000
326 media_state = 0x27; // 0010 0111
331 config_data = 0x00; // 0000 0000
332 media_state = 0x27; // 0010 0111
337 config_data = 0x00; // 0000 0000
338 media_state = 0x00; // 0000 0000
342 SET_BDA(floppy_last_data_rate, config_data);
343 SET_BDA(floppy_media_state[drive], media_state);
348 floppy_ret(struct bregs *regs, u8 code)
351 SET_BDA(floppy_last_status, code);
356 floppy_fail(struct bregs *regs, u8 code)
358 regs->al = 0; // no sectors read
359 floppy_ret(regs, code);
363 check_drive(struct bregs *regs, u8 drive)
365 // see if drive exists
366 if (drive > 1 || !get_drive_type(drive)) {
367 floppy_fail(regs, DISK_RET_ETIMEOUT);
371 // see if media in drive, and type is known
372 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
373 floppy_fail(regs, DISK_RET_EMEDIA);
379 // diskette controller reset
381 floppy_1300(struct bregs *regs, u8 drive)
384 floppy_ret(regs, DISK_RET_EPARAM);
387 if (!get_drive_type(drive)) {
388 floppy_ret(regs, DISK_RET_ETIMEOUT);
391 set_diskette_current_cyl(drive, 0); // current cylinder
392 floppy_ret(regs, DISK_RET_SUCCESS);
395 // Read Diskette Status
397 floppy_1301(struct bregs *regs, u8 drive)
399 u8 v = GET_BDA(floppy_last_status);
404 // Read Diskette Sectors
406 floppy_1302(struct bregs *regs, u8 drive)
408 if (check_drive(regs, drive))
411 u8 num_sectors = regs->al;
413 u8 sector = regs->cl;
416 if (head > 1 || sector == 0 || num_sectors == 0
417 || track > 79 || num_sectors > 72) {
418 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
419 floppy_fail(regs, DISK_RET_EPARAM);
423 // send read-normal-data command (9 bytes) to controller
425 data[0] = 0xe6; // e6: read normal data
426 data[1] = (head << 2) | drive; // HD DR1 DR2
430 data[5] = 2; // 512 byte sector size
431 data[6] = sector + num_sectors - 1; // last sector to read on track
432 data[7] = 0; // Gap length
433 data[8] = 0xff; // Gap length
435 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
437 floppy_fail(regs, ret);
441 if (data[0] & 0xc0) {
442 floppy_fail(regs, DISK_RET_ECONTROLLER);
446 // ??? should track be new val from return_status[3] ?
447 set_diskette_current_cyl(drive, track);
448 // AL = number of sectors read (same value as passed)
449 floppy_ret(regs, DISK_RET_SUCCESS);
452 // Write Diskette Sectors
454 floppy_1303(struct bregs *regs, u8 drive)
456 if (check_drive(regs, drive))
459 u8 num_sectors = regs->al;
461 u8 sector = regs->cl;
464 if (head > 1 || sector == 0 || num_sectors == 0
465 || track > 79 || num_sectors > 72) {
466 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
467 floppy_fail(regs, DISK_RET_EPARAM);
471 // send write-normal-data command (9 bytes) to controller
473 data[0] = 0xc5; // c5: write normal data
474 data[1] = (head << 2) | drive; // HD DR1 DR2
478 data[5] = 2; // 512 byte sector size
479 data[6] = sector + num_sectors - 1; // last sector to write on track
480 data[7] = 0; // Gap length
481 data[8] = 0xff; // Gap length
483 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
485 floppy_fail(regs, ret);
489 if (data[0] & 0xc0) {
490 if (data[1] & 0x02) {
495 BX_PANIC("int13_diskette_function: read error\n");
498 // ??? should track be new val from return_status[3] ?
499 set_diskette_current_cyl(drive, track);
500 // AL = number of sectors read (same value as passed)
501 floppy_ret(regs, DISK_RET_SUCCESS);
504 // Verify Diskette Sectors
506 floppy_1304(struct bregs *regs, u8 drive)
508 if (check_drive(regs, drive))
511 u8 num_sectors = regs->al;
513 u8 sector = regs->cl;
516 if (head > 1 || sector == 0 || num_sectors == 0
517 || track > 79 || num_sectors > 72) {
518 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
519 floppy_fail(regs, DISK_RET_EPARAM);
523 // ??? should track be new val from return_status[3] ?
524 set_diskette_current_cyl(drive, track);
525 // AL = number of sectors verified (same value as passed)
526 floppy_ret(regs, DISK_RET_SUCCESS);
529 // format diskette track
531 floppy_1305(struct bregs *regs, u8 drive)
533 DEBUGF("floppy f05\n");
535 if (check_drive(regs, drive))
538 u8 num_sectors = regs->al;
541 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
542 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
543 floppy_fail(regs, DISK_RET_EPARAM);
547 // send format-track command (6 bytes) to controller
549 data[0] = 0x4d; // 4d: format track
550 data[1] = (head << 2) | drive; // HD DR1 DR2
551 data[2] = 2; // 512 byte sector size
552 data[3] = num_sectors; // number of sectors per track
553 data[4] = 0; // Gap length
554 data[5] = 0xf6; // Fill byte
556 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
558 floppy_fail(regs, ret);
562 if (data[0] & 0xc0) {
563 if (data[1] & 0x02) {
568 BX_PANIC("int13_diskette_function: read error\n");
571 set_diskette_current_cyl(drive, 0);
575 // read diskette drive parameters
577 floppy_1308(struct bregs *regs, u8 drive)
579 DEBUGF("floppy f08\n");
581 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
583 if (drive_type & 0xf0)
585 if (drive_type & 0x0f)
595 regs->dl = num_floppies;
606 regs->bl = drive_type;
609 regs->dl = num_floppies;
611 switch (drive_type) {
614 regs->dh = 0; // max head #
617 case 1: // 360KB, 5.25"
618 regs->cx = 0x2709; // 40 tracks, 9 sectors
619 regs->dh = 1; // max head #
622 case 2: // 1.2MB, 5.25"
623 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
624 regs->dh = 1; // max head #
627 case 3: // 720KB, 3.5"
628 regs->cx = 0x4f09; // 80 tracks, 9 sectors
629 regs->dh = 1; // max head #
632 case 4: // 1.44MB, 3.5"
633 regs->cx = 0x4f12; // 80 tracks, 18 sectors
634 regs->dh = 1; // max head #
637 case 5: // 2.88MB, 3.5"
638 regs->cx = 0x4f24; // 80 tracks, 36 sectors
639 regs->dh = 1; // max head #
642 case 6: // 160k, 5.25"
643 regs->cx = 0x2708; // 40 tracks, 8 sectors
644 regs->dh = 0; // max head #
647 case 7: // 180k, 5.25"
648 regs->cx = 0x2709; // 40 tracks, 9 sectors
649 regs->dh = 0; // max head #
652 case 8: // 320k, 5.25"
653 regs->cx = 0x2708; // 40 tracks, 8 sectors
654 regs->dh = 1; // max head #
658 BX_PANIC("floppy: int13: bad floppy type\n");
661 /* set es & di to point to 11 byte diskette param table in ROM */
663 regs->di = (u16)diskette_param_table2;
664 /* disk status not changed upon success */
667 // read diskette drive type
669 floppy_1315(struct bregs *regs, u8 drive)
671 DEBUGF("floppy f15\n");
673 regs->ah = 0; // only 2 drives supported
674 // set_diskette_ret_status here ???
678 u8 drive_type = get_drive_type(drive);
680 regs->ah = (drive_type != 0);
684 // get diskette change line status
686 floppy_1316(struct bregs *regs, u8 drive)
688 DEBUGF("floppy f16\n");
690 floppy_ret(regs, DISK_RET_EPARAM);
693 floppy_ret(regs, DISK_RET_ECHANGED);
697 floppy_13XX(struct bregs *regs, u8 drive)
699 BX_INFO("int13_diskette: unsupported AH=%02x\n", GET_AH());
700 floppy_ret(regs, DISK_RET_EPARAM);
704 floppy_13(struct bregs *regs, u8 drive)
706 if (CONFIG_FLOPPY_SUPPORT) {
708 case 0x00: floppy_1300(regs, drive); break;
709 case 0x01: floppy_1301(regs, drive); break;
710 case 0x02: floppy_1302(regs, drive); break;
711 case 0x03: floppy_1303(regs, drive); break;
712 case 0x04: floppy_1304(regs, drive); break;
713 case 0x05: floppy_1305(regs, drive); break;
714 case 0x08: floppy_1308(regs, drive); break;
715 case 0x15: floppy_1315(regs, drive); break;
716 case 0x16: floppy_1316(regs, drive); break;
717 default: floppy_13XX(regs, drive); break;
721 case 0x01: floppy_1301(regs, drive); break;
722 default: floppy_13XX(regs, drive); break;
727 // INT 0Eh Diskette Hardware ISR Entry Point
729 handle_0e(struct bregs *regs)
732 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
733 outb(0x08, PORT_FD_DATA); // sense interrupt status
734 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
738 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
741 // diskette interrupt has occurred
742 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
745 // Called from int08 handler.
749 // time to turn off drive(s)?
750 u8 fcount = GET_BDA(floppy_motor_counter);
753 SET_BDA(floppy_motor_counter, fcount);
756 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);