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);
122 } while ((v & FRS_TIMEOUT) == 0);
126 SET_BDA(floppy_recalibration_status, v);
131 floppy_pio(u8 *cmd, u8 cmdlen)
133 floppy_prepare_controller(cmd[1] & 1);
135 // send command to controller
137 for (i=0; i<cmdlen; i++)
138 outb(cmd[i], PORT_FD_DATA);
143 if (!GET_BDA(floppy_motor_counter)) {
145 floppy_reset_controller();
146 return DISK_RET_ETIMEOUT;
148 v = GET_BDA(floppy_recalibration_status);
149 } while (!(v & FRS_TIMEOUT));
153 SET_BDA(floppy_recalibration_status, v);
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 // check port 3f4 for accessibility to status bytes
205 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
206 BX_PANIC("int13_diskette: ctrl not ready\n");
208 // read 7 return status bytes from controller
210 for (i=0; i<7; i++) {
211 u8 v = inb(PORT_FD_DATA);
213 SET_BDA(floppy_return_status[i], v);
220 floppy_drive_recal(u8 drive)
222 // send Recalibrate command (2 bytes) to controller
224 data[0] = 0x07; // 07: Recalibrate
225 data[1] = drive; // 0=drive0, 1=drive1
228 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
229 set_diskette_current_cyl(drive, 0);
233 floppy_media_sense(u8 drive)
236 u8 config_data, media_state;
238 floppy_drive_recal(drive);
240 // for now cheat and get drive type from CMOS,
241 // assume media is same as drive type
244 // Bitfields for diskette media control:
245 // Bit(s) Description (Table M0028)
246 // 7-6 last data rate set by controller
247 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
248 // 5-4 last diskette drive step rate selected
249 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
250 // 3-2 {data rate at start of operation}
254 // Bitfields for diskette drive media state:
255 // Bit(s) Description (Table M0030)
257 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
258 // 5 double stepping required (e.g. 360kB in 1.2MB)
259 // 4 media type established
260 // 3 drive capable of supporting 4MB media
261 // 2-0 on exit from BIOS, contains
262 // 000 trying 360kB in 360kB
263 // 001 trying 360kB in 1.2MB
264 // 010 trying 1.2MB in 1.2MB
265 // 011 360kB in 360kB established
266 // 100 360kB in 1.2MB established
267 // 101 1.2MB in 1.2MB established
269 // 111 all other formats/drives
271 switch (get_drive_type(drive)) {
274 config_data = 0x00; // 0000 0000
275 media_state = 0x25; // 0010 0101
279 // 1.2 MB 5.25" drive
280 config_data = 0x00; // 0000 0000
281 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
286 config_data = 0x00; // 0000 0000 ???
287 media_state = 0x17; // 0001 0111
291 // 1.44 MB 3.5" drive
292 config_data = 0x00; // 0000 0000
293 media_state = 0x17; // 0001 0111
297 // 2.88 MB 3.5" drive
298 config_data = 0xCC; // 1100 1100
299 media_state = 0xD7; // 1101 0111
303 // Extended floppy size uses special cmos setting
306 config_data = 0x00; // 0000 0000
307 media_state = 0x27; // 0010 0111
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 = 0x00; // 0000 0000
329 SET_BDA(floppy_last_data_rate, config_data);
330 SET_BDA(floppy_media_state[drive], media_state);
335 floppy_ret(struct bregs *regs, u8 code)
338 SET_BDA(floppy_last_status, code);
343 floppy_fail(struct bregs *regs, u8 code)
345 regs->al = 0; // no sectors read
346 floppy_ret(regs, code);
350 check_drive(struct bregs *regs, u8 drive)
352 // see if drive exists
353 if (drive > 1 || !get_drive_type(drive)) {
354 // XXX - return type doesn't match
355 floppy_fail(regs, DISK_RET_ETIMEOUT);
359 // see if media in drive, and type is known
360 if (floppy_media_known(drive) == 0 && floppy_media_sense(drive) == 0) {
361 floppy_fail(regs, DISK_RET_EMEDIA);
367 // diskette controller reset
369 floppy_1300(struct bregs *regs, u8 drive)
372 floppy_ret(regs, DISK_RET_EPARAM);
375 if (!get_drive_type(drive)) {
376 floppy_ret(regs, DISK_RET_ETIMEOUT);
379 set_diskette_current_cyl(drive, 0); // current cylinder
380 floppy_ret(regs, DISK_RET_SUCCESS);
383 // Read Diskette Status
385 floppy_1301(struct bregs *regs, u8 drive)
387 u8 v = GET_BDA(floppy_last_status);
392 // Read Diskette Sectors
394 floppy_1302(struct bregs *regs, u8 drive)
396 if (check_drive(regs, drive))
399 u8 num_sectors = regs->al;
401 u8 sector = regs->cl;
404 if (head > 1 || sector == 0 || num_sectors == 0
405 || track > 79 || num_sectors > 72) {
406 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
407 floppy_fail(regs, DISK_RET_EPARAM);
411 // send read-normal-data command (9 bytes) to controller
413 data[0] = 0xe6; // e6: read normal data
414 data[1] = (head << 2) | drive; // HD DR1 DR2
418 data[5] = 2; // 512 byte sector size
419 data[6] = sector + num_sectors - 1; // last sector to read on track
420 data[7] = 0; // Gap length
421 data[8] = 0xff; // Gap length
423 u16 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
425 floppy_fail(regs, ret);
429 if (data[0] & 0xc0) {
430 floppy_fail(regs, DISK_RET_ECONTROLLER);
434 // ??? should track be new val from return_status[3] ?
435 set_diskette_current_cyl(drive, track);
436 // AL = number of sectors read (same value as passed)
437 floppy_ret(regs, DISK_RET_SUCCESS);
440 // Write Diskette Sectors
442 floppy_1303(struct bregs *regs, u8 drive)
444 if (check_drive(regs, drive))
447 u8 num_sectors = regs->al;
449 u8 sector = regs->cl;
452 if (head > 1 || sector == 0 || num_sectors == 0
453 || track > 79 || num_sectors > 72) {
454 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
455 floppy_fail(regs, DISK_RET_EPARAM);
459 // send write-normal-data command (9 bytes) to controller
461 data[0] = 0xc5; // c5: write normal data
462 data[1] = (head << 2) | drive; // HD DR1 DR2
466 data[5] = 2; // 512 byte sector size
467 data[6] = sector + num_sectors - 1; // last sector to write on track
468 data[7] = 0; // Gap length
469 data[8] = 0xff; // Gap length
471 u8 ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
473 floppy_fail(regs, ret);
477 if (data[0] & 0xc0) {
478 if (data[1] & 0x02) {
483 BX_PANIC("int13_diskette_function: read error\n");
486 // ??? should track be new val from return_status[3] ?
487 set_diskette_current_cyl(drive, track);
488 // AL = number of sectors read (same value as passed)
489 floppy_ret(regs, DISK_RET_SUCCESS);
492 // Verify Diskette Sectors
494 floppy_1304(struct bregs *regs, u8 drive)
496 if (check_drive(regs, drive))
499 u8 num_sectors = regs->al;
501 u8 sector = regs->cl;
504 if (head > 1 || sector == 0 || num_sectors == 0
505 || track > 79 || num_sectors > 72) {
506 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
507 floppy_fail(regs, DISK_RET_EPARAM);
511 // ??? should track be new val from return_status[3] ?
512 set_diskette_current_cyl(drive, track);
513 // AL = number of sectors verified (same value as passed)
514 floppy_ret(regs, DISK_RET_SUCCESS);
517 // format diskette track
519 floppy_1305(struct bregs *regs, u8 drive)
521 DEBUGF("floppy f05\n");
523 if (check_drive(regs, drive))
526 u8 num_sectors = regs->al;
529 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
530 BX_INFO("int13_diskette: read/write/verify: parameter out of range\n");
531 floppy_fail(regs, DISK_RET_EPARAM);
535 // send format-track command (6 bytes) to controller
537 data[0] = 0x4d; // 4d: format track
538 data[1] = (head << 2) | drive; // HD DR1 DR2
539 data[2] = 2; // 512 byte sector size
540 data[3] = num_sectors; // number of sectors per track
541 data[4] = 0; // Gap length
542 data[5] = 0xf6; // Fill byte
544 u8 ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
546 floppy_fail(regs, ret);
550 if (data[0] & 0xc0) {
551 if (data[1] & 0x02) {
556 BX_PANIC("int13_diskette_function: read error\n");
559 set_diskette_current_cyl(drive, 0);
563 // read diskette drive parameters
565 floppy_1308(struct bregs *regs, u8 drive)
567 DEBUGF("floppy f08\n");
569 u8 drive_type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
571 if (drive_type & 0xf0)
573 if (drive_type & 0x0f)
583 regs->dl = num_floppies;
594 regs->bl = drive_type;
597 regs->dl = num_floppies;
599 switch (drive_type) {
602 regs->dh = 0; // max head #
605 case 1: // 360KB, 5.25"
606 regs->cx = 0x2709; // 40 tracks, 9 sectors
607 regs->dh = 1; // max head #
610 case 2: // 1.2MB, 5.25"
611 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
612 regs->dh = 1; // max head #
615 case 3: // 720KB, 3.5"
616 regs->cx = 0x4f09; // 80 tracks, 9 sectors
617 regs->dh = 1; // max head #
620 case 4: // 1.44MB, 3.5"
621 regs->cx = 0x4f12; // 80 tracks, 18 sectors
622 regs->dh = 1; // max head #
625 case 5: // 2.88MB, 3.5"
626 regs->cx = 0x4f24; // 80 tracks, 36 sectors
627 regs->dh = 1; // max head #
630 case 6: // 160k, 5.25"
631 regs->cx = 0x2708; // 40 tracks, 8 sectors
632 regs->dh = 0; // max head #
635 case 7: // 180k, 5.25"
636 regs->cx = 0x2709; // 40 tracks, 9 sectors
637 regs->dh = 0; // max head #
640 case 8: // 320k, 5.25"
641 regs->cx = 0x2708; // 40 tracks, 8 sectors
642 regs->dh = 1; // max head #
646 BX_PANIC("floppy: int13: bad floppy type\n");
649 /* set es & di to point to 11 byte diskette param table in ROM */
651 regs->di = (u16)&diskette_param_table2;
652 /* disk status not changed upon success */
655 // read diskette drive type
657 floppy_1315(struct bregs *regs, u8 drive)
659 DEBUGF("floppy f15\n");
661 regs->ah = 0; // only 2 drives supported
662 // set_diskette_ret_status here ???
666 u8 drive_type = get_drive_type(drive);
668 regs->ah = (drive_type != 0);
672 // get diskette change line status
674 floppy_1316(struct bregs *regs, u8 drive)
676 DEBUGF("floppy f16\n");
678 floppy_ret(regs, DISK_RET_EPARAM);
681 floppy_ret(regs, DISK_RET_ECHANGED);
685 floppy_13XX(struct bregs *regs, u8 drive)
687 BX_INFO("int13_diskette: unsupported AH=%02x\n", regs->ah);
688 floppy_ret(regs, DISK_RET_EPARAM);
692 floppy_13(struct bregs *regs, u8 drive)
694 if (! CONFIG_FLOPPY_SUPPORT) {
697 case 0x01: floppy_1301(regs, drive); break;
698 default: floppy_13XX(regs, drive); break;
703 case 0x00: floppy_1300(regs, drive); break;
704 case 0x01: floppy_1301(regs, drive); break;
705 case 0x02: floppy_1302(regs, drive); break;
706 case 0x03: floppy_1303(regs, drive); break;
707 case 0x04: floppy_1304(regs, drive); break;
708 case 0x05: floppy_1305(regs, drive); break;
709 case 0x08: floppy_1308(regs, drive); break;
710 case 0x15: floppy_1315(regs, drive); break;
711 case 0x16: floppy_1316(regs, drive); break;
712 default: floppy_13XX(regs, drive); break;
716 // INT 0Eh Diskette Hardware ISR Entry Point
718 handle_0e(struct bregs *regs)
721 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
722 outb(0x08, PORT_FD_DATA); // sense interrupt status
723 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
727 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
730 // diskette interrupt has occurred
731 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
734 // Called from int08 handler.
738 // time to turn off drive(s)?
739 u8 fcount = GET_BDA(floppy_motor_counter);
742 SET_BDA(floppy_motor_counter, fcount);
745 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);