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" // SET_BDA
12 #include "util.h" // irq_disable
13 #include "cmos.h" // inb_cmos
14 #include "pic.h" // unmask_pic1
15 #include "bregs.h" // struct bregs
17 #define BX_FLOPPY_ON_CNT 37 /* 2 seconds */
19 // New diskette parameter table adding 3 parameters from IBM
20 // Since no provisions are made for multiple drive types, most
21 // values in this table are ignored. I set parameters for 1.44M
23 struct floppy_ext_dbt_s diskette_param_table2 VISIBLE16 = {
26 .specify2 = 0x02, // head load time 0000001, DMA used
27 .shutoff_ticks = 0x25,
30 .interblock_len = 0x1B,
37 .max_track = 79, // maximum track
38 .data_rate = 0, // data transfer rate
39 .drive_type = 4, // drive type in cmos
45 if (! CONFIG_FLOPPY_SUPPORT)
47 dprintf(3, "init floppy drives\n");
48 u8 type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
60 SET_BDA(floppy_harddisk_info, out);
62 // Update equipment word bits for floppy
63 if (num_floppies == 1)
64 // 1 drive, ready for boot
65 SETBITS_BDA(equipment_list_flags, 0x01);
66 else if (num_floppies == 2)
67 // 2 drives, ready for boot
68 SETBITS_BDA(equipment_list_flags, 0x41);
70 outb(0x02, PORT_DMA1_MASK_REG);
72 // Enable IRQ6 (handle_0e)
73 unmask_pic1(PIC1_IRQ6);
77 set_diskette_current_cyl(u8 drive, u8 cyl)
80 SET_BDA(floppy_track1, cyl);
82 SET_BDA(floppy_track0, cyl);
86 get_drive_type(u8 drive)
88 // check CMOS to see if drive exists
89 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
98 floppy_media_known(u8 drive)
100 if (!(GET_BDA(floppy_recalibration_status) & (1<<drive)))
102 u8 v = GET_BDA(floppy_media_state[drive]);
103 if (!(v & FMS_MEDIA_DRIVE_ESTABLISHED))
109 floppy_reset_controller()
112 u8 val8 = inb(PORT_FD_DOR);
113 outb(val8 & ~0x04, PORT_FD_DOR);
114 outb(val8 | 0x04, PORT_FD_DOR);
116 // Wait for controller to come out of reset
117 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
122 floppy_prepare_controller(u8 drive)
124 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
126 // turn on motor of selected drive, DMA & int enabled, normal operation
127 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
133 outb(dor, PORT_FD_DOR);
135 // reset the disk motor timeout value of INT 08
136 SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
138 // wait for drive readiness
139 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
142 if (prev_reset == 0) {
146 v = GET_BDA(floppy_recalibration_status);
154 SET_BDA(floppy_recalibration_status, v);
159 floppy_pio(u8 *cmd, u8 cmdlen)
161 floppy_prepare_controller(cmd[1] & 1);
163 // send command to controller
165 for (i=0; i<cmdlen; i++)
166 outb(cmd[i], PORT_FD_DATA);
171 if (!GET_BDA(floppy_motor_counter)) {
173 floppy_reset_controller();
174 return DISK_RET_ETIMEOUT;
176 v = GET_BDA(floppy_recalibration_status);
184 SET_BDA(floppy_recalibration_status, v);
190 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
192 // es:bx = pointer to where to place information from diskette
193 // port 04: DMA-1 base and current address, channel 2
194 // port 05: DMA-1 base and current count, channel 2
195 u16 page = regs->es >> 12; // upper 4 bits
196 u16 base_es = regs->es << 4; // lower 16bits contributed by ES
197 u16 base_address = base_es + regs->bx; // lower 16 bits of address
198 // contributed by ES:BX
199 if (base_address < base_es)
200 // in case of carry, adjust page by 1
203 // check for 64K boundary overrun
204 u16 last_addr = base_address + count;
205 if (last_addr < base_address)
206 return DISK_RET_EBOUNDARY;
208 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
211 mode_register = 0x46;
213 //DEBUGF("floppy dma c2\n");
214 outb(0x06, PORT_DMA1_MASK_REG);
215 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
216 outb(base_address, PORT_DMA_ADDR_2);
217 outb(base_address>>8, PORT_DMA_ADDR_2);
218 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
219 outb(count, PORT_DMA_CNT_2);
220 outb(count>>8, PORT_DMA_CNT_2);
222 // port 0b: DMA-1 Mode Register
223 // transfer type=write, channel 2
224 outb(mode_register, PORT_DMA1_MODE_REG);
226 // port 81: DMA-1 Page Register, channel 2
227 outb(page, PORT_DMA_PAGE_2);
229 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
231 u8 ret = floppy_pio(cmd, cmdlen);
235 // check port 3f4 for accessibility to status bytes
236 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
237 BX_PANIC("int13_diskette: ctrl not ready\n");
239 // read 7 return status bytes from controller
241 for (i=0; i<7; i++) {
242 u8 v = inb(PORT_FD_DATA);
244 SET_BDA(floppy_return_status[i], v);
251 floppy_drive_recal(u8 drive)
253 // send Recalibrate command (2 bytes) to controller
255 data[0] = 0x07; // 07: Recalibrate
256 data[1] = drive; // 0=drive0, 1=drive1
259 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
260 set_diskette_current_cyl(drive, 0);
264 floppy_media_sense(u8 drive)
267 u8 config_data, media_state;
269 floppy_drive_recal(drive);
271 // for now cheat and get drive type from CMOS,
272 // assume media is same as drive type
275 // Bitfields for diskette media control:
276 // Bit(s) Description (Table M0028)
277 // 7-6 last data rate set by controller
278 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
279 // 5-4 last diskette drive step rate selected
280 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
281 // 3-2 {data rate at start of operation}
285 // Bitfields for diskette drive media state:
286 // Bit(s) Description (Table M0030)
288 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
289 // 5 double stepping required (e.g. 360kB in 1.2MB)
290 // 4 media type established
291 // 3 drive capable of supporting 4MB media
292 // 2-0 on exit from BIOS, contains
293 // 000 trying 360kB in 360kB
294 // 001 trying 360kB in 1.2MB
295 // 010 trying 1.2MB in 1.2MB
296 // 011 360kB in 360kB established
297 // 100 360kB in 1.2MB established
298 // 101 1.2MB in 1.2MB established
300 // 111 all other formats/drives
302 switch (get_drive_type(drive)) {
305 config_data = 0x00; // 0000 0000
306 media_state = 0x25; // 0010 0101
310 // 1.2 MB 5.25" drive
311 config_data = 0x00; // 0000 0000
312 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
317 config_data = 0x00; // 0000 0000 ???
318 media_state = 0x17; // 0001 0111
322 // 1.44 MB 3.5" drive
323 config_data = 0x00; // 0000 0000
324 media_state = 0x17; // 0001 0111
328 // 2.88 MB 3.5" drive
329 config_data = 0xCC; // 1100 1100
330 media_state = 0xD7; // 1101 0111
334 // Extended floppy size uses special cmos setting
337 config_data = 0x00; // 0000 0000
338 media_state = 0x27; // 0010 0111
343 config_data = 0x00; // 0000 0000
344 media_state = 0x27; // 0010 0111
349 config_data = 0x00; // 0000 0000
350 media_state = 0x27; // 0010 0111
355 config_data = 0x00; // 0000 0000
356 media_state = 0x00; // 0000 0000
360 SET_BDA(floppy_last_data_rate, config_data);
361 SET_BDA(floppy_media_state[drive], media_state);
365 #define floppy_ret(regs, code) \
366 __floppy_ret(__func__, (regs), (code))
369 __floppy_ret(const char *fname, struct bregs *regs, u8 code)
371 SET_BDA(floppy_last_status, code);
373 __set_code_fail(fname, regs, code);
375 set_code_success(regs);
379 floppy_fail(struct bregs *regs, u8 code)
381 floppy_ret(regs, code);
382 regs->al = 0; // no sectors read
386 check_drive(struct bregs *regs, u8 drive)
388 // see if drive exists
389 if (drive > 1 || !get_drive_type(drive)) {
390 // XXX - return type doesn't match
391 floppy_fail(regs, DISK_RET_ETIMEOUT);
395 // see if media in drive, and type is known
396 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
397 floppy_fail(regs, DISK_RET_EMEDIA);
403 // diskette controller reset
405 floppy_1300(struct bregs *regs, u8 drive)
408 floppy_ret(regs, DISK_RET_EPARAM);
411 if (!get_drive_type(drive)) {
412 floppy_ret(regs, DISK_RET_ETIMEOUT);
415 set_diskette_current_cyl(drive, 0); // current cylinder
416 floppy_ret(regs, DISK_RET_SUCCESS);
419 // Read Diskette Status
421 floppy_1301(struct bregs *regs, u8 drive)
423 u8 v = GET_BDA(floppy_last_status);
428 // Read Diskette Sectors
430 floppy_1302(struct bregs *regs, u8 drive)
432 if (check_drive(regs, drive))
435 u8 num_sectors = regs->al;
437 u8 sector = regs->cl;
440 if (head > 1 || sector == 0 || num_sectors == 0
441 || track > 79 || num_sectors > 72) {
442 floppy_fail(regs, DISK_RET_EPARAM);
446 // send read-normal-data command (9 bytes) to controller
448 data[0] = 0xe6; // e6: read normal data
449 data[1] = (head << 2) | drive; // HD DR1 DR2
453 data[5] = 2; // 512 byte sector size
454 data[6] = sector + num_sectors - 1; // last sector to read on track
455 data[7] = 0; // Gap length
456 data[8] = 0xff; // Gap length
458 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
460 floppy_fail(regs, ret);
464 if (data[0] & 0xc0) {
465 floppy_fail(regs, DISK_RET_ECONTROLLER);
469 // ??? should track be new val from return_status[3] ?
470 set_diskette_current_cyl(drive, track);
471 // AL = number of sectors read (same value as passed)
472 floppy_ret(regs, DISK_RET_SUCCESS);
475 // Write Diskette Sectors
477 floppy_1303(struct bregs *regs, u8 drive)
479 if (check_drive(regs, drive))
482 u8 num_sectors = regs->al;
484 u8 sector = regs->cl;
487 if (head > 1 || sector == 0 || num_sectors == 0
488 || track > 79 || num_sectors > 72) {
489 floppy_fail(regs, DISK_RET_EPARAM);
493 // send write-normal-data command (9 bytes) to controller
495 data[0] = 0xc5; // c5: write normal data
496 data[1] = (head << 2) | drive; // HD DR1 DR2
500 data[5] = 2; // 512 byte sector size
501 data[6] = sector + num_sectors - 1; // last sector to write on track
502 data[7] = 0; // Gap length
503 data[8] = 0xff; // Gap length
505 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
507 floppy_fail(regs, ret);
511 if (data[0] & 0xc0) {
512 if (data[1] & 0x02) {
517 BX_PANIC("int13_diskette_function: read error\n");
520 // ??? should track be new val from return_status[3] ?
521 set_diskette_current_cyl(drive, track);
522 // AL = number of sectors read (same value as passed)
523 floppy_ret(regs, DISK_RET_SUCCESS);
526 // Verify Diskette Sectors
528 floppy_1304(struct bregs *regs, u8 drive)
530 if (check_drive(regs, drive))
533 u8 num_sectors = regs->al;
535 u8 sector = regs->cl;
538 if (head > 1 || sector == 0 || num_sectors == 0
539 || track > 79 || num_sectors > 72) {
540 floppy_fail(regs, DISK_RET_EPARAM);
544 // ??? should track be new val from return_status[3] ?
545 set_diskette_current_cyl(drive, track);
546 // AL = number of sectors verified (same value as passed)
547 floppy_ret(regs, DISK_RET_SUCCESS);
550 // format diskette track
552 floppy_1305(struct bregs *regs, u8 drive)
554 dprintf(3, "floppy f05\n");
556 if (check_drive(regs, drive))
559 u8 num_sectors = regs->al;
562 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
563 floppy_fail(regs, DISK_RET_EPARAM);
567 // send format-track command (6 bytes) to controller
569 data[0] = 0x4d; // 4d: format track
570 data[1] = (head << 2) | drive; // HD DR1 DR2
571 data[2] = 2; // 512 byte sector size
572 data[3] = num_sectors; // number of sectors per track
573 data[4] = 0; // Gap length
574 data[5] = 0xf6; // Fill byte
576 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
578 floppy_fail(regs, ret);
582 if (data[0] & 0xc0) {
583 if (data[1] & 0x02) {
588 BX_PANIC("int13_diskette_function: read error\n");
591 set_diskette_current_cyl(drive, 0);
595 // read diskette drive parameters
597 floppy_1308(struct bregs *regs, u8 drive)
599 dprintf(3, "floppy f08\n");
601 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
603 if (drive_type & 0xf0)
605 if (drive_type & 0x0f)
615 regs->dl = num_floppies;
626 regs->bl = drive_type;
629 regs->dl = num_floppies;
631 switch (drive_type) {
634 regs->dh = 0; // max head #
637 case 1: // 360KB, 5.25"
638 regs->cx = 0x2709; // 40 tracks, 9 sectors
639 regs->dh = 1; // max head #
642 case 2: // 1.2MB, 5.25"
643 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
644 regs->dh = 1; // max head #
647 case 3: // 720KB, 3.5"
648 regs->cx = 0x4f09; // 80 tracks, 9 sectors
649 regs->dh = 1; // max head #
652 case 4: // 1.44MB, 3.5"
653 regs->cx = 0x4f12; // 80 tracks, 18 sectors
654 regs->dh = 1; // max head #
657 case 5: // 2.88MB, 3.5"
658 regs->cx = 0x4f24; // 80 tracks, 36 sectors
659 regs->dh = 1; // max head #
662 case 6: // 160k, 5.25"
663 regs->cx = 0x2708; // 40 tracks, 8 sectors
664 regs->dh = 0; // max head #
667 case 7: // 180k, 5.25"
668 regs->cx = 0x2709; // 40 tracks, 9 sectors
669 regs->dh = 0; // max head #
672 case 8: // 320k, 5.25"
673 regs->cx = 0x2708; // 40 tracks, 8 sectors
674 regs->dh = 1; // max head #
678 BX_PANIC("floppy: int13: bad floppy type\n");
681 /* set es & di to point to 11 byte diskette param table in ROM */
683 regs->di = (u32)&diskette_param_table2;
684 /* disk status not changed upon success */
687 // read diskette drive type
689 floppy_1315(struct bregs *regs, u8 drive)
691 dprintf(6, "floppy f15\n");
694 regs->ah = 0; // only 2 drives supported
695 // set_diskette_ret_status here ???
698 u8 drive_type = get_drive_type(drive);
700 regs->ah = (drive_type != 0);
704 // get diskette change line status
706 floppy_1316(struct bregs *regs, u8 drive)
709 floppy_ret(regs, DISK_RET_EPARAM);
712 floppy_ret(regs, DISK_RET_ECHANGED);
716 floppy_13XX(struct bregs *regs, u8 drive)
718 floppy_ret(regs, DISK_RET_EPARAM);
722 floppy_13(struct bregs *regs, u8 drive)
724 if (! CONFIG_FLOPPY_SUPPORT) {
727 case 0x01: floppy_1301(regs, drive); break;
728 default: floppy_13XX(regs, drive); break;
733 case 0x00: floppy_1300(regs, drive); break;
734 case 0x01: floppy_1301(regs, drive); break;
735 case 0x02: floppy_1302(regs, drive); break;
736 case 0x03: floppy_1303(regs, drive); break;
737 case 0x04: floppy_1304(regs, drive); break;
738 case 0x05: floppy_1305(regs, drive); break;
739 case 0x08: floppy_1308(regs, drive); break;
740 case 0x15: floppy_1315(regs, drive); break;
741 case 0x16: floppy_1316(regs, drive); break;
742 default: floppy_13XX(regs, drive); break;
746 // INT 0Eh Diskette Hardware ISR Entry Point
750 debug_isr(DEBUG_ISR_0e);
751 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
752 outb(0x08, PORT_FD_DATA); // sense interrupt status
753 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
757 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
760 // diskette interrupt has occurred
761 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
764 // Called from int08 handler.
768 // time to turn off drive(s)?
769 u8 fcount = GET_BDA(floppy_motor_counter);
772 SET_BDA(floppy_motor_counter, fcount);
775 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);