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 // New diskette parameter table adding 3 parameters from IBM
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 struct floppy_ext_dbt_s diskette_param_table2 VISIBLE = {
24 .specify2 = 0x02, // head load time 0000001, DMA used
25 .shutoff_ticks = 0x25,
28 .interblock_len = 0x1B,
35 .max_track = 79, // maximum track
36 .data_rate = 0, // data transfer rate
37 .drive_type = 4, // drive type in cmos
41 // Return codes vary greatly - AL not cleared consistenlty, BDA return
42 // status not set consistently, sometimes panics.
43 // Extra outb(0x000a, 0x02) in read?
44 // Does not disable interrupts on failure paths.
45 // numfloppies used before set in int_1308
46 // int_1305 verifies track but doesn't use it?
49 set_diskette_current_cyl(u8 drive, u8 cyl)
52 SET_BDA(floppy_track1, cyl);
54 SET_BDA(floppy_track0, cyl);
58 get_drive_type(u8 drive)
60 // check CMOS to see if drive exists
61 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
70 floppy_media_known(u8 drive)
72 if (!(GET_BDA(floppy_recalibration_status) & (1<<drive)))
74 u8 v = GET_BDA(floppy_media_state[drive]);
75 if (!(v & FMS_MEDIA_DRIVE_ESTABLISHED))
81 floppy_reset_controller()
84 u8 val8 = inb(PORT_FD_DOR);
85 outb(val8 & ~0x04, PORT_FD_DOR);
86 outb(val8 | 0x04, PORT_FD_DOR);
88 // Wait for controller to come out of reset
89 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
94 floppy_prepare_controller(u8 drive)
96 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
98 // turn on motor of selected drive, DMA & int enabled, normal operation
99 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
105 outb(dor, PORT_FD_DOR);
107 // reset the disk motor timeout value of INT 08
108 SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
110 // wait for drive readiness
111 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
114 if (prev_reset == 0) {
118 v = GET_BDA(floppy_recalibration_status);
119 } while ((v & FRS_TIMEOUT) == 0);
123 SET_BDA(floppy_recalibration_status, v);
128 floppy_pio(u8 *cmd, u8 cmdlen)
130 floppy_prepare_controller(cmd[1] & 1);
132 // send command to controller
134 for (i=0; i<cmdlen; i++)
135 outb(cmd[i], PORT_FD_DATA);
140 if (!GET_BDA(floppy_motor_counter)) {
142 floppy_reset_controller();
143 return DISK_RET_ETIMEOUT;
145 v = GET_BDA(floppy_recalibration_status);
146 } while (!(v & FRS_TIMEOUT));
150 SET_BDA(floppy_recalibration_status, v);
152 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
153 BX_PANIC("int13_diskette: ctrl not ready\n");
159 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
161 // es:bx = pointer to where to place information from diskette
162 // port 04: DMA-1 base and current address, channel 2
163 // port 05: DMA-1 base and current count, channel 2
164 u16 page = regs->es >> 12; // upper 4 bits
165 u16 base_es = regs->es << 4; // lower 16bits contributed by ES
166 u16 base_address = base_es + regs->bx; // lower 16 bits of address
167 // contributed by ES:BX
168 if (base_address < base_es)
169 // in case of carry, adjust page by 1
172 // check for 64K boundary overrun
173 u16 last_addr = base_address + count;
174 if (last_addr < base_address)
175 return DISK_RET_EBOUNDARY;
177 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
180 mode_register = 0x46;
182 //DEBUGF("floppy dma c2\n");
183 outb(0x06, PORT_DMA1_MASK_REG);
184 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
185 outb(base_address, PORT_DMA_ADDR_2);
186 outb(base_address>>8, PORT_DMA_ADDR_2);
187 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
188 outb(count, PORT_DMA_CNT_2);
189 outb(count>>8, PORT_DMA_CNT_2);
191 // port 0b: DMA-1 Mode Register
192 // transfer type=write, channel 2
193 outb(mode_register, PORT_DMA1_MODE_REG);
195 // port 81: DMA-1 Page Register, channel 2
196 outb(page, PORT_DMA_PAGE_2);
198 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
200 u8 ret = floppy_pio(cmd, cmdlen);
204 // read 7 return status bytes from controller
206 for (i=0; i<7; i++) {
207 u8 v = inb(PORT_FD_DATA);
209 SET_BDA(floppy_return_status[i], v);
216 floppy_drive_recal(u8 drive)
218 // send Recalibrate command (2 bytes) to controller
220 data[0] = 0x07; // 07: Recalibrate
221 data[1] = drive; // 0=drive0, 1=drive1
224 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
225 set_diskette_current_cyl(drive, 0);
229 floppy_media_sense(u8 drive)
232 u8 config_data, media_state;
234 floppy_drive_recal(drive);
236 // for now cheat and get drive type from CMOS,
237 // assume media is same as drive type
240 // Bitfields for diskette media control:
241 // Bit(s) Description (Table M0028)
242 // 7-6 last data rate set by controller
243 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
244 // 5-4 last diskette drive step rate selected
245 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
246 // 3-2 {data rate at start of operation}
250 // Bitfields for diskette drive media state:
251 // Bit(s) Description (Table M0030)
253 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
254 // 5 double stepping required (e.g. 360kB in 1.2MB)
255 // 4 media type established
256 // 3 drive capable of supporting 4MB media
257 // 2-0 on exit from BIOS, contains
258 // 000 trying 360kB in 360kB
259 // 001 trying 360kB in 1.2MB
260 // 010 trying 1.2MB in 1.2MB
261 // 011 360kB in 360kB established
262 // 100 360kB in 1.2MB established
263 // 101 1.2MB in 1.2MB established
265 // 111 all other formats/drives
267 switch (get_drive_type(drive)) {
270 config_data = 0x00; // 0000 0000
271 media_state = 0x25; // 0010 0101
275 // 1.2 MB 5.25" drive
276 config_data = 0x00; // 0000 0000
277 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
282 config_data = 0x00; // 0000 0000 ???
283 media_state = 0x17; // 0001 0111
287 // 1.44 MB 3.5" drive
288 config_data = 0x00; // 0000 0000
289 media_state = 0x17; // 0001 0111
293 // 2.88 MB 3.5" drive
294 config_data = 0xCC; // 1100 1100
295 media_state = 0xD7; // 1101 0111
299 // Extended floppy size uses special cmos setting
302 config_data = 0x00; // 0000 0000
303 media_state = 0x27; // 0010 0111
308 config_data = 0x00; // 0000 0000
309 media_state = 0x27; // 0010 0111
314 config_data = 0x00; // 0000 0000
315 media_state = 0x27; // 0010 0111
320 config_data = 0x00; // 0000 0000
321 media_state = 0x00; // 0000 0000
325 SET_BDA(floppy_last_data_rate, config_data);
326 SET_BDA(floppy_media_state[drive], media_state);
331 floppy_ret(struct bregs *regs, u8 code)
334 SET_BDA(floppy_last_status, code);
339 floppy_fail(struct bregs *regs, u8 code)
341 regs->al = 0; // no sectors read
342 floppy_ret(regs, code);
346 check_drive(struct bregs *regs, u8 drive)
348 // see if drive exists
349 if (drive > 1 || !get_drive_type(drive)) {
350 floppy_fail(regs, DISK_RET_ETIMEOUT);
354 // see if media in drive, and type is known
355 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
356 floppy_fail(regs, DISK_RET_EMEDIA);
362 // diskette controller reset
364 floppy_1300(struct bregs *regs, u8 drive)
367 floppy_ret(regs, DISK_RET_EPARAM);
370 if (!get_drive_type(drive)) {
371 floppy_ret(regs, DISK_RET_ETIMEOUT);
374 set_diskette_current_cyl(drive, 0); // current cylinder
375 floppy_ret(regs, DISK_RET_SUCCESS);
378 // Read Diskette Status
380 floppy_1301(struct bregs *regs, u8 drive)
382 u8 v = GET_BDA(floppy_last_status);
387 // Read Diskette Sectors
389 floppy_1302(struct bregs *regs, u8 drive)
391 if (check_drive(regs, drive))
394 u8 num_sectors = regs->al;
396 u8 sector = regs->cl;
399 if (head > 1 || sector == 0 || num_sectors == 0
400 || track > 79 || num_sectors > 72) {
401 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
402 floppy_fail(regs, DISK_RET_EPARAM);
406 // send read-normal-data command (9 bytes) to controller
408 data[0] = 0xe6; // e6: read normal data
409 data[1] = (head << 2) | drive; // HD DR1 DR2
413 data[5] = 2; // 512 byte sector size
414 data[6] = sector + num_sectors - 1; // last sector to read on track
415 data[7] = 0; // Gap length
416 data[8] = 0xff; // Gap length
418 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
420 floppy_fail(regs, ret);
424 if (data[0] & 0xc0) {
425 floppy_fail(regs, DISK_RET_ECONTROLLER);
429 // ??? should track be new val from return_status[3] ?
430 set_diskette_current_cyl(drive, track);
431 // AL = number of sectors read (same value as passed)
432 floppy_ret(regs, DISK_RET_SUCCESS);
435 // Write Diskette Sectors
437 floppy_1303(struct bregs *regs, u8 drive)
439 if (check_drive(regs, drive))
442 u8 num_sectors = regs->al;
444 u8 sector = regs->cl;
447 if (head > 1 || sector == 0 || num_sectors == 0
448 || track > 79 || num_sectors > 72) {
449 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
450 floppy_fail(regs, DISK_RET_EPARAM);
454 // send write-normal-data command (9 bytes) to controller
456 data[0] = 0xc5; // c5: write normal data
457 data[1] = (head << 2) | drive; // HD DR1 DR2
461 data[5] = 2; // 512 byte sector size
462 data[6] = sector + num_sectors - 1; // last sector to write on track
463 data[7] = 0; // Gap length
464 data[8] = 0xff; // Gap length
466 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
468 floppy_fail(regs, ret);
472 if (data[0] & 0xc0) {
473 if (data[1] & 0x02) {
478 BX_PANIC("int13_diskette_function: read error\n");
481 // ??? should track be new val from return_status[3] ?
482 set_diskette_current_cyl(drive, track);
483 // AL = number of sectors read (same value as passed)
484 floppy_ret(regs, DISK_RET_SUCCESS);
487 // Verify Diskette Sectors
489 floppy_1304(struct bregs *regs, u8 drive)
491 if (check_drive(regs, drive))
494 u8 num_sectors = regs->al;
496 u8 sector = regs->cl;
499 if (head > 1 || sector == 0 || num_sectors == 0
500 || track > 79 || num_sectors > 72) {
501 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
502 floppy_fail(regs, DISK_RET_EPARAM);
506 // ??? should track be new val from return_status[3] ?
507 set_diskette_current_cyl(drive, track);
508 // AL = number of sectors verified (same value as passed)
509 floppy_ret(regs, DISK_RET_SUCCESS);
512 // format diskette track
514 floppy_1305(struct bregs *regs, u8 drive)
516 DEBUGF("floppy f05\n");
518 if (check_drive(regs, drive))
521 u8 num_sectors = regs->al;
524 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
525 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
526 floppy_fail(regs, DISK_RET_EPARAM);
530 // send format-track command (6 bytes) to controller
532 data[0] = 0x4d; // 4d: format track
533 data[1] = (head << 2) | drive; // HD DR1 DR2
534 data[2] = 2; // 512 byte sector size
535 data[3] = num_sectors; // number of sectors per track
536 data[4] = 0; // Gap length
537 data[5] = 0xf6; // Fill byte
539 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
541 floppy_fail(regs, ret);
545 if (data[0] & 0xc0) {
546 if (data[1] & 0x02) {
551 BX_PANIC("int13_diskette_function: read error\n");
554 set_diskette_current_cyl(drive, 0);
558 // read diskette drive parameters
560 floppy_1308(struct bregs *regs, u8 drive)
562 DEBUGF("floppy f08\n");
564 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
566 if (drive_type & 0xf0)
568 if (drive_type & 0x0f)
578 regs->dl = num_floppies;
589 regs->bl = drive_type;
592 regs->dl = num_floppies;
594 switch (drive_type) {
597 regs->dh = 0; // max head #
600 case 1: // 360KB, 5.25"
601 regs->cx = 0x2709; // 40 tracks, 9 sectors
602 regs->dh = 1; // max head #
605 case 2: // 1.2MB, 5.25"
606 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
607 regs->dh = 1; // max head #
610 case 3: // 720KB, 3.5"
611 regs->cx = 0x4f09; // 80 tracks, 9 sectors
612 regs->dh = 1; // max head #
615 case 4: // 1.44MB, 3.5"
616 regs->cx = 0x4f12; // 80 tracks, 18 sectors
617 regs->dh = 1; // max head #
620 case 5: // 2.88MB, 3.5"
621 regs->cx = 0x4f24; // 80 tracks, 36 sectors
622 regs->dh = 1; // max head #
625 case 6: // 160k, 5.25"
626 regs->cx = 0x2708; // 40 tracks, 8 sectors
627 regs->dh = 0; // max head #
630 case 7: // 180k, 5.25"
631 regs->cx = 0x2709; // 40 tracks, 9 sectors
632 regs->dh = 0; // max head #
635 case 8: // 320k, 5.25"
636 regs->cx = 0x2708; // 40 tracks, 8 sectors
637 regs->dh = 1; // max head #
641 BX_PANIC("floppy: int13: bad floppy type\n");
644 /* set es & di to point to 11 byte diskette param table in ROM */
646 regs->di = (u16)&diskette_param_table2;
647 /* disk status not changed upon success */
650 // read diskette drive type
652 floppy_1315(struct bregs *regs, u8 drive)
654 DEBUGF("floppy f15\n");
656 regs->ah = 0; // only 2 drives supported
657 // set_diskette_ret_status here ???
661 u8 drive_type = get_drive_type(drive);
663 regs->ah = (drive_type != 0);
667 // get diskette change line status
669 floppy_1316(struct bregs *regs, u8 drive)
671 DEBUGF("floppy f16\n");
673 floppy_ret(regs, DISK_RET_EPARAM);
676 floppy_ret(regs, DISK_RET_ECHANGED);
680 floppy_13XX(struct bregs *regs, u8 drive)
682 BX_INFO("int13_diskette: unsupported AH=%02x\n", regs->ah);
683 floppy_ret(regs, DISK_RET_EPARAM);
687 floppy_13(struct bregs *regs, u8 drive)
689 if (! CONFIG_FLOPPY_SUPPORT) {
692 case 0x01: floppy_1301(regs, drive); break;
693 default: floppy_13XX(regs, drive); break;
698 case 0x00: floppy_1300(regs, drive); break;
699 case 0x01: floppy_1301(regs, drive); break;
700 case 0x02: floppy_1302(regs, drive); break;
701 case 0x03: floppy_1303(regs, drive); break;
702 case 0x04: floppy_1304(regs, drive); break;
703 case 0x05: floppy_1305(regs, drive); break;
704 case 0x08: floppy_1308(regs, drive); break;
705 case 0x15: floppy_1315(regs, drive); break;
706 case 0x16: floppy_1316(regs, drive); break;
707 default: floppy_13XX(regs, drive); break;
711 // INT 0Eh Diskette Hardware ISR Entry Point
713 handle_0e(struct bregs *regs)
716 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
717 outb(0x08, PORT_FD_DATA); // sense interrupt status
718 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
722 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
725 // diskette interrupt has occurred
726 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
729 // Called from int08 handler.
733 // time to turn off drive(s)?
734 u8 fcount = GET_BDA(floppy_motor_counter);
737 SET_BDA(floppy_motor_counter, fcount);
740 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);