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
44 // Return codes vary greatly - AL not cleared consistenlty, BDA return
45 // status not set consistently, sometimes panics.
46 // Extra outb(0x000a, 0x02) in read?
47 // Does not disable interrupts on failure paths.
48 // numfloppies used before set in int_1308
49 // int_1305 verifies track but doesn't use it?
52 set_diskette_current_cyl(u8 drive, u8 cyl)
55 SET_BDA(floppy_track1, cyl);
57 SET_BDA(floppy_track0, cyl);
61 get_drive_type(u8 drive)
63 // check CMOS to see if drive exists
64 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
73 floppy_media_known(u8 drive)
75 if (!(GET_BDA(floppy_recalibration_status) & (1<<drive)))
77 u8 v = GET_BDA(floppy_media_state[drive]);
78 if (!(v & FMS_MEDIA_DRIVE_ESTABLISHED))
84 floppy_reset_controller()
87 u8 val8 = inb(PORT_FD_DOR);
88 outb(val8 & ~0x04, PORT_FD_DOR);
89 outb(val8 | 0x04, PORT_FD_DOR);
91 // Wait for controller to come out of reset
92 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
97 floppy_prepare_controller(u8 drive)
99 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
101 // turn on motor of selected drive, DMA & int enabled, normal operation
102 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
108 outb(dor, PORT_FD_DOR);
110 // reset the disk motor timeout value of INT 08
111 SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
113 // wait for drive readiness
114 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
117 if (prev_reset == 0) {
121 v = GET_BDA(floppy_recalibration_status);
129 SET_BDA(floppy_recalibration_status, v);
134 floppy_pio(u8 *cmd, u8 cmdlen)
136 floppy_prepare_controller(cmd[1] & 1);
138 // send command to controller
140 for (i=0; i<cmdlen; i++)
141 outb(cmd[i], PORT_FD_DATA);
146 if (!GET_BDA(floppy_motor_counter)) {
148 floppy_reset_controller();
149 return DISK_RET_ETIMEOUT;
151 v = GET_BDA(floppy_recalibration_status);
159 SET_BDA(floppy_recalibration_status, v);
165 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
167 // es:bx = pointer to where to place information from diskette
168 // port 04: DMA-1 base and current address, channel 2
169 // port 05: DMA-1 base and current count, channel 2
170 u16 page = regs->es >> 12; // upper 4 bits
171 u16 base_es = regs->es << 4; // lower 16bits contributed by ES
172 u16 base_address = base_es + regs->bx; // lower 16 bits of address
173 // contributed by ES:BX
174 if (base_address < base_es)
175 // in case of carry, adjust page by 1
178 // check for 64K boundary overrun
179 u16 last_addr = base_address + count;
180 if (last_addr < base_address)
181 return DISK_RET_EBOUNDARY;
183 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
186 mode_register = 0x46;
188 //DEBUGF("floppy dma c2\n");
189 outb(0x06, PORT_DMA1_MASK_REG);
190 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
191 outb(base_address, PORT_DMA_ADDR_2);
192 outb(base_address>>8, PORT_DMA_ADDR_2);
193 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
194 outb(count, PORT_DMA_CNT_2);
195 outb(count>>8, PORT_DMA_CNT_2);
197 // port 0b: DMA-1 Mode Register
198 // transfer type=write, channel 2
199 outb(mode_register, PORT_DMA1_MODE_REG);
201 // port 81: DMA-1 Page Register, channel 2
202 outb(page, PORT_DMA_PAGE_2);
204 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
206 u8 ret = floppy_pio(cmd, cmdlen);
210 // check port 3f4 for accessibility to status bytes
211 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
212 BX_PANIC("int13_diskette: ctrl not ready\n");
214 // read 7 return status bytes from controller
216 for (i=0; i<7; i++) {
217 u8 v = inb(PORT_FD_DATA);
219 SET_BDA(floppy_return_status[i], v);
226 floppy_drive_recal(u8 drive)
228 // send Recalibrate command (2 bytes) to controller
230 data[0] = 0x07; // 07: Recalibrate
231 data[1] = drive; // 0=drive0, 1=drive1
234 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
235 set_diskette_current_cyl(drive, 0);
239 floppy_media_sense(u8 drive)
242 u8 config_data, media_state;
244 floppy_drive_recal(drive);
246 // for now cheat and get drive type from CMOS,
247 // assume media is same as drive type
250 // Bitfields for diskette media control:
251 // Bit(s) Description (Table M0028)
252 // 7-6 last data rate set by controller
253 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
254 // 5-4 last diskette drive step rate selected
255 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
256 // 3-2 {data rate at start of operation}
260 // Bitfields for diskette drive media state:
261 // Bit(s) Description (Table M0030)
263 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
264 // 5 double stepping required (e.g. 360kB in 1.2MB)
265 // 4 media type established
266 // 3 drive capable of supporting 4MB media
267 // 2-0 on exit from BIOS, contains
268 // 000 trying 360kB in 360kB
269 // 001 trying 360kB in 1.2MB
270 // 010 trying 1.2MB in 1.2MB
271 // 011 360kB in 360kB established
272 // 100 360kB in 1.2MB established
273 // 101 1.2MB in 1.2MB established
275 // 111 all other formats/drives
277 switch (get_drive_type(drive)) {
280 config_data = 0x00; // 0000 0000
281 media_state = 0x25; // 0010 0101
285 // 1.2 MB 5.25" drive
286 config_data = 0x00; // 0000 0000
287 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
292 config_data = 0x00; // 0000 0000 ???
293 media_state = 0x17; // 0001 0111
297 // 1.44 MB 3.5" drive
298 config_data = 0x00; // 0000 0000
299 media_state = 0x17; // 0001 0111
303 // 2.88 MB 3.5" drive
304 config_data = 0xCC; // 1100 1100
305 media_state = 0xD7; // 1101 0111
309 // Extended floppy size uses special cmos setting
312 config_data = 0x00; // 0000 0000
313 media_state = 0x27; // 0010 0111
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 = 0x00; // 0000 0000
335 SET_BDA(floppy_last_data_rate, config_data);
336 SET_BDA(floppy_media_state[drive], media_state);
341 floppy_ret(struct bregs *regs, u8 code)
343 SET_BDA(floppy_last_status, code);
345 set_code_fail(regs, code);
347 set_code_success(regs);
351 floppy_fail(struct bregs *regs, u8 code)
353 floppy_ret(regs, code);
354 regs->al = 0; // no sectors read
358 check_drive(struct bregs *regs, u8 drive)
360 // see if drive exists
361 if (drive > 1 || !get_drive_type(drive)) {
362 // XXX - return type doesn't match
363 floppy_fail(regs, DISK_RET_ETIMEOUT);
367 // see if media in drive, and type is known
368 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
369 floppy_fail(regs, DISK_RET_EMEDIA);
375 // diskette controller reset
377 floppy_1300(struct bregs *regs, u8 drive)
380 floppy_ret(regs, DISK_RET_EPARAM);
383 if (!get_drive_type(drive)) {
384 floppy_ret(regs, DISK_RET_ETIMEOUT);
387 set_diskette_current_cyl(drive, 0); // current cylinder
388 floppy_ret(regs, DISK_RET_SUCCESS);
391 // Read Diskette Status
393 floppy_1301(struct bregs *regs, u8 drive)
395 u8 v = GET_BDA(floppy_last_status);
400 // Read Diskette Sectors
402 floppy_1302(struct bregs *regs, u8 drive)
404 if (check_drive(regs, drive))
407 u8 num_sectors = regs->al;
409 u8 sector = regs->cl;
412 if (head > 1 || sector == 0 || num_sectors == 0
413 || track > 79 || num_sectors > 72) {
414 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
415 floppy_fail(regs, DISK_RET_EPARAM);
419 // send read-normal-data command (9 bytes) to controller
421 data[0] = 0xe6; // e6: read normal data
422 data[1] = (head << 2) | drive; // HD DR1 DR2
426 data[5] = 2; // 512 byte sector size
427 data[6] = sector + num_sectors - 1; // last sector to read on track
428 data[7] = 0; // Gap length
429 data[8] = 0xff; // Gap length
431 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
433 floppy_fail(regs, ret);
437 if (data[0] & 0xc0) {
438 floppy_fail(regs, DISK_RET_ECONTROLLER);
442 // ??? should track be new val from return_status[3] ?
443 set_diskette_current_cyl(drive, track);
444 // AL = number of sectors read (same value as passed)
445 floppy_ret(regs, DISK_RET_SUCCESS);
448 // Write Diskette Sectors
450 floppy_1303(struct bregs *regs, u8 drive)
452 if (check_drive(regs, drive))
455 u8 num_sectors = regs->al;
457 u8 sector = regs->cl;
460 if (head > 1 || sector == 0 || num_sectors == 0
461 || track > 79 || num_sectors > 72) {
462 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
463 floppy_fail(regs, DISK_RET_EPARAM);
467 // send write-normal-data command (9 bytes) to controller
469 data[0] = 0xc5; // c5: write normal data
470 data[1] = (head << 2) | drive; // HD DR1 DR2
474 data[5] = 2; // 512 byte sector size
475 data[6] = sector + num_sectors - 1; // last sector to write on track
476 data[7] = 0; // Gap length
477 data[8] = 0xff; // Gap length
479 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
481 floppy_fail(regs, ret);
485 if (data[0] & 0xc0) {
486 if (data[1] & 0x02) {
491 BX_PANIC("int13_diskette_function: read error\n");
494 // ??? should track be new val from return_status[3] ?
495 set_diskette_current_cyl(drive, track);
496 // AL = number of sectors read (same value as passed)
497 floppy_ret(regs, DISK_RET_SUCCESS);
500 // Verify Diskette Sectors
502 floppy_1304(struct bregs *regs, u8 drive)
504 if (check_drive(regs, drive))
507 u8 num_sectors = regs->al;
509 u8 sector = regs->cl;
512 if (head > 1 || sector == 0 || num_sectors == 0
513 || track > 79 || num_sectors > 72) {
514 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
515 floppy_fail(regs, DISK_RET_EPARAM);
519 // ??? should track be new val from return_status[3] ?
520 set_diskette_current_cyl(drive, track);
521 // AL = number of sectors verified (same value as passed)
522 floppy_ret(regs, DISK_RET_SUCCESS);
525 // format diskette track
527 floppy_1305(struct bregs *regs, u8 drive)
529 DEBUGF("floppy f05\n");
531 if (check_drive(regs, drive))
534 u8 num_sectors = regs->al;
537 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
538 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
539 floppy_fail(regs, DISK_RET_EPARAM);
543 // send format-track command (6 bytes) to controller
545 data[0] = 0x4d; // 4d: format track
546 data[1] = (head << 2) | drive; // HD DR1 DR2
547 data[2] = 2; // 512 byte sector size
548 data[3] = num_sectors; // number of sectors per track
549 data[4] = 0; // Gap length
550 data[5] = 0xf6; // Fill byte
552 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
554 floppy_fail(regs, ret);
558 if (data[0] & 0xc0) {
559 if (data[1] & 0x02) {
564 BX_PANIC("int13_diskette_function: read error\n");
567 set_diskette_current_cyl(drive, 0);
571 // read diskette drive parameters
573 floppy_1308(struct bregs *regs, u8 drive)
575 DEBUGF("floppy f08\n");
577 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
579 if (drive_type & 0xf0)
581 if (drive_type & 0x0f)
591 regs->dl = num_floppies;
602 regs->bl = drive_type;
605 regs->dl = num_floppies;
607 switch (drive_type) {
610 regs->dh = 0; // max head #
613 case 1: // 360KB, 5.25"
614 regs->cx = 0x2709; // 40 tracks, 9 sectors
615 regs->dh = 1; // max head #
618 case 2: // 1.2MB, 5.25"
619 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
620 regs->dh = 1; // max head #
623 case 3: // 720KB, 3.5"
624 regs->cx = 0x4f09; // 80 tracks, 9 sectors
625 regs->dh = 1; // max head #
628 case 4: // 1.44MB, 3.5"
629 regs->cx = 0x4f12; // 80 tracks, 18 sectors
630 regs->dh = 1; // max head #
633 case 5: // 2.88MB, 3.5"
634 regs->cx = 0x4f24; // 80 tracks, 36 sectors
635 regs->dh = 1; // max head #
638 case 6: // 160k, 5.25"
639 regs->cx = 0x2708; // 40 tracks, 8 sectors
640 regs->dh = 0; // max head #
643 case 7: // 180k, 5.25"
644 regs->cx = 0x2709; // 40 tracks, 9 sectors
645 regs->dh = 0; // max head #
648 case 8: // 320k, 5.25"
649 regs->cx = 0x2708; // 40 tracks, 8 sectors
650 regs->dh = 1; // max head #
654 BX_PANIC("floppy: int13: bad floppy type\n");
657 /* set es & di to point to 11 byte diskette param table in ROM */
659 regs->di = (u16)&diskette_param_table2;
660 /* disk status not changed upon success */
663 // read diskette drive type
665 floppy_1315(struct bregs *regs, u8 drive)
667 DEBUGF("floppy f15\n");
670 regs->ah = 0; // only 2 drives supported
671 // set_diskette_ret_status here ???
674 u8 drive_type = get_drive_type(drive);
676 regs->ah = (drive_type != 0);
680 // get diskette change line status
682 floppy_1316(struct bregs *regs, u8 drive)
684 DEBUGF("floppy f16\n");
686 floppy_ret(regs, DISK_RET_EPARAM);
689 floppy_ret(regs, DISK_RET_ECHANGED);
693 floppy_13XX(struct bregs *regs, u8 drive)
695 BX_INFO("int13_diskette: unsupported AH=%02x\n", regs->ah);
696 floppy_ret(regs, DISK_RET_EPARAM);
700 floppy_13(struct bregs *regs, u8 drive)
702 if (! CONFIG_FLOPPY_SUPPORT) {
705 case 0x01: floppy_1301(regs, drive); break;
706 default: floppy_13XX(regs, drive); break;
711 case 0x00: floppy_1300(regs, drive); break;
712 case 0x01: floppy_1301(regs, drive); break;
713 case 0x02: floppy_1302(regs, drive); break;
714 case 0x03: floppy_1303(regs, drive); break;
715 case 0x04: floppy_1304(regs, drive); break;
716 case 0x05: floppy_1305(regs, drive); break;
717 case 0x08: floppy_1308(regs, drive); break;
718 case 0x15: floppy_1315(regs, drive); break;
719 case 0x16: floppy_1316(regs, drive); break;
720 default: floppy_13XX(regs, drive); break;
724 // INT 0Eh Diskette Hardware ISR Entry Point
729 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
730 outb(0x08, PORT_FD_DATA); // sense interrupt status
731 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
735 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
738 // diskette interrupt has occurred
739 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
742 // Called from int08 handler.
746 // time to turn off drive(s)?
747 u8 fcount = GET_BDA(floppy_motor_counter);
750 SET_BDA(floppy_motor_counter, fcount);
753 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);