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 u8 type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
52 SET_BDA(floppy_harddisk_info, out);
53 outb(0x02, PORT_DMA1_MASK_REG);
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);
142 SET_BDA(floppy_recalibration_status, v);
147 floppy_pio(u8 *cmd, u8 cmdlen)
149 floppy_prepare_controller(cmd[1] & 1);
151 // send command to controller
153 for (i=0; i<cmdlen; i++)
154 outb(cmd[i], PORT_FD_DATA);
159 if (!GET_BDA(floppy_motor_counter)) {
161 floppy_reset_controller();
162 return DISK_RET_ETIMEOUT;
164 v = GET_BDA(floppy_recalibration_status);
172 SET_BDA(floppy_recalibration_status, v);
178 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
180 // es:bx = pointer to where to place information from diskette
181 // port 04: DMA-1 base and current address, channel 2
182 // port 05: DMA-1 base and current count, channel 2
183 u16 page = regs->es >> 12; // upper 4 bits
184 u16 base_es = regs->es << 4; // lower 16bits contributed by ES
185 u16 base_address = base_es + regs->bx; // lower 16 bits of address
186 // contributed by ES:BX
187 if (base_address < base_es)
188 // in case of carry, adjust page by 1
191 // check for 64K boundary overrun
192 u16 last_addr = base_address + count;
193 if (last_addr < base_address)
194 return DISK_RET_EBOUNDARY;
196 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
199 mode_register = 0x46;
201 //DEBUGF("floppy dma c2\n");
202 outb(0x06, PORT_DMA1_MASK_REG);
203 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
204 outb(base_address, PORT_DMA_ADDR_2);
205 outb(base_address>>8, PORT_DMA_ADDR_2);
206 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
207 outb(count, PORT_DMA_CNT_2);
208 outb(count>>8, PORT_DMA_CNT_2);
210 // port 0b: DMA-1 Mode Register
211 // transfer type=write, channel 2
212 outb(mode_register, PORT_DMA1_MODE_REG);
214 // port 81: DMA-1 Page Register, channel 2
215 outb(page, PORT_DMA_PAGE_2);
217 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
219 u8 ret = floppy_pio(cmd, cmdlen);
223 // check port 3f4 for accessibility to status bytes
224 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
225 BX_PANIC("int13_diskette: ctrl not ready\n");
227 // read 7 return status bytes from controller
229 for (i=0; i<7; i++) {
230 u8 v = inb(PORT_FD_DATA);
232 SET_BDA(floppy_return_status[i], v);
239 floppy_drive_recal(u8 drive)
241 // send Recalibrate command (2 bytes) to controller
243 data[0] = 0x07; // 07: Recalibrate
244 data[1] = drive; // 0=drive0, 1=drive1
247 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
248 set_diskette_current_cyl(drive, 0);
252 floppy_media_sense(u8 drive)
255 u8 config_data, media_state;
257 floppy_drive_recal(drive);
259 // for now cheat and get drive type from CMOS,
260 // assume media is same as drive type
263 // Bitfields for diskette media control:
264 // Bit(s) Description (Table M0028)
265 // 7-6 last data rate set by controller
266 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
267 // 5-4 last diskette drive step rate selected
268 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
269 // 3-2 {data rate at start of operation}
273 // Bitfields for diskette drive media state:
274 // Bit(s) Description (Table M0030)
276 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
277 // 5 double stepping required (e.g. 360kB in 1.2MB)
278 // 4 media type established
279 // 3 drive capable of supporting 4MB media
280 // 2-0 on exit from BIOS, contains
281 // 000 trying 360kB in 360kB
282 // 001 trying 360kB in 1.2MB
283 // 010 trying 1.2MB in 1.2MB
284 // 011 360kB in 360kB established
285 // 100 360kB in 1.2MB established
286 // 101 1.2MB in 1.2MB established
288 // 111 all other formats/drives
290 switch (get_drive_type(drive)) {
293 config_data = 0x00; // 0000 0000
294 media_state = 0x25; // 0010 0101
298 // 1.2 MB 5.25" drive
299 config_data = 0x00; // 0000 0000
300 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
305 config_data = 0x00; // 0000 0000 ???
306 media_state = 0x17; // 0001 0111
310 // 1.44 MB 3.5" drive
311 config_data = 0x00; // 0000 0000
312 media_state = 0x17; // 0001 0111
316 // 2.88 MB 3.5" drive
317 config_data = 0xCC; // 1100 1100
318 media_state = 0xD7; // 1101 0111
322 // Extended floppy size uses special cmos setting
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 = 0x27; // 0010 0111
343 config_data = 0x00; // 0000 0000
344 media_state = 0x00; // 0000 0000
348 SET_BDA(floppy_last_data_rate, config_data);
349 SET_BDA(floppy_media_state[drive], media_state);
354 floppy_ret(struct bregs *regs, u8 code)
356 SET_BDA(floppy_last_status, code);
358 set_code_fail(regs, code);
360 set_code_success(regs);
364 floppy_fail(struct bregs *regs, u8 code)
366 floppy_ret(regs, code);
367 regs->al = 0; // no sectors read
371 check_drive(struct bregs *regs, u8 drive)
373 // see if drive exists
374 if (drive > 1 || !get_drive_type(drive)) {
375 // XXX - return type doesn't match
376 floppy_fail(regs, DISK_RET_ETIMEOUT);
380 // see if media in drive, and type is known
381 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
382 floppy_fail(regs, DISK_RET_EMEDIA);
388 // diskette controller reset
390 floppy_1300(struct bregs *regs, u8 drive)
393 floppy_ret(regs, DISK_RET_EPARAM);
396 if (!get_drive_type(drive)) {
397 floppy_ret(regs, DISK_RET_ETIMEOUT);
400 set_diskette_current_cyl(drive, 0); // current cylinder
401 floppy_ret(regs, DISK_RET_SUCCESS);
404 // Read Diskette Status
406 floppy_1301(struct bregs *regs, u8 drive)
408 u8 v = GET_BDA(floppy_last_status);
413 // Read Diskette Sectors
415 floppy_1302(struct bregs *regs, u8 drive)
417 if (check_drive(regs, drive))
420 u8 num_sectors = regs->al;
422 u8 sector = regs->cl;
425 if (head > 1 || sector == 0 || num_sectors == 0
426 || track > 79 || num_sectors > 72) {
427 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
428 floppy_fail(regs, DISK_RET_EPARAM);
432 // send read-normal-data command (9 bytes) to controller
434 data[0] = 0xe6; // e6: read normal data
435 data[1] = (head << 2) | drive; // HD DR1 DR2
439 data[5] = 2; // 512 byte sector size
440 data[6] = sector + num_sectors - 1; // last sector to read on track
441 data[7] = 0; // Gap length
442 data[8] = 0xff; // Gap length
444 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
446 floppy_fail(regs, ret);
450 if (data[0] & 0xc0) {
451 floppy_fail(regs, DISK_RET_ECONTROLLER);
455 // ??? should track be new val from return_status[3] ?
456 set_diskette_current_cyl(drive, track);
457 // AL = number of sectors read (same value as passed)
458 floppy_ret(regs, DISK_RET_SUCCESS);
461 // Write Diskette Sectors
463 floppy_1303(struct bregs *regs, u8 drive)
465 if (check_drive(regs, drive))
468 u8 num_sectors = regs->al;
470 u8 sector = regs->cl;
473 if (head > 1 || sector == 0 || num_sectors == 0
474 || track > 79 || num_sectors > 72) {
475 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
476 floppy_fail(regs, DISK_RET_EPARAM);
480 // send write-normal-data command (9 bytes) to controller
482 data[0] = 0xc5; // c5: write normal data
483 data[1] = (head << 2) | drive; // HD DR1 DR2
487 data[5] = 2; // 512 byte sector size
488 data[6] = sector + num_sectors - 1; // last sector to write on track
489 data[7] = 0; // Gap length
490 data[8] = 0xff; // Gap length
492 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
494 floppy_fail(regs, ret);
498 if (data[0] & 0xc0) {
499 if (data[1] & 0x02) {
504 BX_PANIC("int13_diskette_function: read error\n");
507 // ??? should track be new val from return_status[3] ?
508 set_diskette_current_cyl(drive, track);
509 // AL = number of sectors read (same value as passed)
510 floppy_ret(regs, DISK_RET_SUCCESS);
513 // Verify Diskette Sectors
515 floppy_1304(struct bregs *regs, u8 drive)
517 if (check_drive(regs, drive))
520 u8 num_sectors = regs->al;
522 u8 sector = regs->cl;
525 if (head > 1 || sector == 0 || num_sectors == 0
526 || track > 79 || num_sectors > 72) {
527 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
528 floppy_fail(regs, DISK_RET_EPARAM);
532 // ??? should track be new val from return_status[3] ?
533 set_diskette_current_cyl(drive, track);
534 // AL = number of sectors verified (same value as passed)
535 floppy_ret(regs, DISK_RET_SUCCESS);
538 // format diskette track
540 floppy_1305(struct bregs *regs, u8 drive)
542 DEBUGF("floppy f05\n");
544 if (check_drive(regs, drive))
547 u8 num_sectors = regs->al;
550 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
551 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
552 floppy_fail(regs, DISK_RET_EPARAM);
556 // send format-track command (6 bytes) to controller
558 data[0] = 0x4d; // 4d: format track
559 data[1] = (head << 2) | drive; // HD DR1 DR2
560 data[2] = 2; // 512 byte sector size
561 data[3] = num_sectors; // number of sectors per track
562 data[4] = 0; // Gap length
563 data[5] = 0xf6; // Fill byte
565 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
567 floppy_fail(regs, ret);
571 if (data[0] & 0xc0) {
572 if (data[1] & 0x02) {
577 BX_PANIC("int13_diskette_function: read error\n");
580 set_diskette_current_cyl(drive, 0);
584 // read diskette drive parameters
586 floppy_1308(struct bregs *regs, u8 drive)
588 DEBUGF("floppy f08\n");
590 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
592 if (drive_type & 0xf0)
594 if (drive_type & 0x0f)
604 regs->dl = num_floppies;
615 regs->bl = drive_type;
618 regs->dl = num_floppies;
620 switch (drive_type) {
623 regs->dh = 0; // max head #
626 case 1: // 360KB, 5.25"
627 regs->cx = 0x2709; // 40 tracks, 9 sectors
628 regs->dh = 1; // max head #
631 case 2: // 1.2MB, 5.25"
632 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
633 regs->dh = 1; // max head #
636 case 3: // 720KB, 3.5"
637 regs->cx = 0x4f09; // 80 tracks, 9 sectors
638 regs->dh = 1; // max head #
641 case 4: // 1.44MB, 3.5"
642 regs->cx = 0x4f12; // 80 tracks, 18 sectors
643 regs->dh = 1; // max head #
646 case 5: // 2.88MB, 3.5"
647 regs->cx = 0x4f24; // 80 tracks, 36 sectors
648 regs->dh = 1; // max head #
651 case 6: // 160k, 5.25"
652 regs->cx = 0x2708; // 40 tracks, 8 sectors
653 regs->dh = 0; // max head #
656 case 7: // 180k, 5.25"
657 regs->cx = 0x2709; // 40 tracks, 9 sectors
658 regs->dh = 0; // max head #
661 case 8: // 320k, 5.25"
662 regs->cx = 0x2708; // 40 tracks, 8 sectors
663 regs->dh = 1; // max head #
667 BX_PANIC("floppy: int13: bad floppy type\n");
670 /* set es & di to point to 11 byte diskette param table in ROM */
672 regs->di = (u16)&diskette_param_table2;
673 /* disk status not changed upon success */
676 // read diskette drive type
678 floppy_1315(struct bregs *regs, u8 drive)
680 DEBUGF("floppy f15\n");
683 regs->ah = 0; // only 2 drives supported
684 // set_diskette_ret_status here ???
687 u8 drive_type = get_drive_type(drive);
689 regs->ah = (drive_type != 0);
693 // get diskette change line status
695 floppy_1316(struct bregs *regs, u8 drive)
697 DEBUGF("floppy f16\n");
699 floppy_ret(regs, DISK_RET_EPARAM);
702 floppy_ret(regs, DISK_RET_ECHANGED);
706 floppy_13XX(struct bregs *regs, u8 drive)
708 BX_INFO("int13_diskette: unsupported AH=%02x\n", regs->ah);
709 floppy_ret(regs, DISK_RET_EPARAM);
713 floppy_13(struct bregs *regs, u8 drive)
715 if (! CONFIG_FLOPPY_SUPPORT) {
718 case 0x01: floppy_1301(regs, drive); break;
719 default: floppy_13XX(regs, drive); break;
724 case 0x00: floppy_1300(regs, drive); break;
725 case 0x01: floppy_1301(regs, drive); break;
726 case 0x02: floppy_1302(regs, drive); break;
727 case 0x03: floppy_1303(regs, drive); break;
728 case 0x04: floppy_1304(regs, drive); break;
729 case 0x05: floppy_1305(regs, drive); break;
730 case 0x08: floppy_1308(regs, drive); break;
731 case 0x15: floppy_1315(regs, drive); break;
732 case 0x16: floppy_1316(regs, drive); break;
733 default: floppy_13XX(regs, drive); break;
737 // INT 0Eh Diskette Hardware ISR Entry Point
742 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
743 outb(0x08, PORT_FD_DATA); // sense interrupt status
744 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
748 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
751 // diskette interrupt has occurred
752 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
755 // Called from int08 handler.
759 // time to turn off drive(s)?
760 u8 fcount = GET_BDA(floppy_motor_counter);
763 SET_BDA(floppy_motor_counter, fcount);
766 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);