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 LGPLv3 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" // eoi_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 VAR16_32 = {
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
42 // Since no provisions are made for multiple drive types, most
43 // values in this table are ignored. I set parameters for 1.44M
45 struct floppy_dbt_s diskette_param_table VAR16FIXED(0xefc7) = {
47 .specify2 = 0x02, // head load time 0000001, DMA used
48 .shutoff_ticks = 0x25,
51 .interblock_len = 0x1B,
59 u8 FloppyCount VAR16_32;
60 u8 FloppyTypes[2] VAR16_32;
65 if (! CONFIG_FLOPPY_SUPPORT)
67 dprintf(3, "init floppy drives\n");
69 FloppyTypes[0] = FloppyTypes[1] = 0;
72 if (CONFIG_COREBOOT) {
73 // XXX - disable floppies on coreboot for now.
75 u8 type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
78 FloppyTypes[0] = type >> 4;
83 FloppyTypes[1] = type & 0x0f;
87 SET_BDA(floppy_harddisk_info, out);
89 // Update equipment word bits for floppy
91 // 1 drive, ready for boot
92 SETBITS_BDA(equipment_list_flags, 0x01);
93 else if (FloppyCount == 2)
94 // 2 drives, ready for boot
95 SETBITS_BDA(equipment_list_flags, 0x41);
97 outb(0x02, PORT_DMA1_MASK_REG);
99 enable_hwirq(6, entry_0e);
102 #define floppy_ret(regs, code) \
103 __floppy_ret((regs), (code) | (__LINE__ << 8), __func__)
106 __floppy_ret(struct bregs *regs, u32 linecode, const char *fname)
109 SET_BDA(floppy_last_status, code);
111 __set_code_fail(regs, linecode, fname);
113 set_code_success(regs);
117 /****************************************************************
118 * Low-level floppy IO
119 ****************************************************************/
122 floppy_reset_controller()
125 u8 val8 = inb(PORT_FD_DOR);
126 outb(val8 & ~0x04, PORT_FD_DOR);
127 outb(val8 | 0x04, PORT_FD_DOR);
129 // Wait for controller to come out of reset
130 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
140 if (!GET_BDA(floppy_motor_counter)) {
144 v = GET_BDA(floppy_recalibration_status);
152 SET_BDA(floppy_recalibration_status, v);
157 floppy_prepare_controller(u8 drive)
159 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
161 // turn on motor of selected drive, DMA & int enabled, normal operation
162 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
168 outb(dor, PORT_FD_DOR);
170 // reset the disk motor timeout value of INT 08
171 SET_BDA(floppy_motor_counter, BX_FLOPPY_ON_CNT);
173 // wait for drive readiness
174 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
182 floppy_pio(u8 *cmd, u8 cmdlen)
184 floppy_prepare_controller(cmd[1] & 1);
186 // send command to controller
188 for (i=0; i<cmdlen; i++)
189 outb(cmd[i], PORT_FD_DATA);
191 int ret = wait_floppy_irq();
193 floppy_reset_controller();
201 floppy_cmd(struct bregs *regs, u16 count, u8 *cmd, u8 cmdlen)
203 // es:bx = pointer to where to place information from diskette
204 u32 addr = (u32)MAKE_FLATPTR(regs->es, regs->bx);
206 // check for 64K boundary overrun
207 u32 last_addr = addr + count;
208 if ((addr >> 16) != (last_addr >> 16)) {
209 floppy_ret(regs, DISK_RET_EBOUNDARY);
213 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
216 mode_register = 0x46;
218 //DEBUGF("floppy dma c2\n");
219 outb(0x06, PORT_DMA1_MASK_REG);
220 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
221 outb(addr, PORT_DMA_ADDR_2);
222 outb(addr>>8, PORT_DMA_ADDR_2);
223 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
224 outb(count, PORT_DMA_CNT_2);
225 outb(count>>8, PORT_DMA_CNT_2);
227 // port 0b: DMA-1 Mode Register
228 // transfer type=write, channel 2
229 outb(mode_register, PORT_DMA1_MODE_REG);
231 // port 81: DMA-1 Page Register, channel 2
232 outb(addr>>16, PORT_DMA_PAGE_2);
234 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
236 int ret = floppy_pio(cmd, cmdlen);
238 floppy_ret(regs, DISK_RET_ETIMEOUT);
242 // check port 3f4 for accessibility to status bytes
243 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
244 floppy_ret(regs, DISK_RET_ECONTROLLER);
248 // read 7 return status bytes from controller
250 for (i=0; i<7; i++) {
251 u8 v = inb(PORT_FD_DATA);
253 SET_BDA(floppy_return_status[i], v);
260 /****************************************************************
262 ****************************************************************/
265 set_diskette_current_cyl(u8 drive, u8 cyl)
267 SET_BDA(floppy_track[drive], cyl);
271 floppy_drive_recal(u8 drive)
273 // send Recalibrate command (2 bytes) to controller
275 data[0] = 0x07; // 07: Recalibrate
276 data[1] = drive; // 0=drive0, 1=drive1
279 SETBITS_BDA(floppy_recalibration_status, 1<<drive);
280 set_diskette_current_cyl(drive, 0);
284 floppy_media_sense(u8 drive)
286 // for now cheat and get drive type from CMOS,
287 // assume media is same as drive type
290 // Bitfields for diskette media control:
291 // Bit(s) Description (Table M0028)
292 // 7-6 last data rate set by controller
293 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
294 // 5-4 last diskette drive step rate selected
295 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
296 // 3-2 {data rate at start of operation}
300 // Bitfields for diskette drive media state:
301 // Bit(s) Description (Table M0030)
303 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
304 // 5 double stepping required (e.g. 360kB in 1.2MB)
305 // 4 media type established
306 // 3 drive capable of supporting 4MB media
307 // 2-0 on exit from BIOS, contains
308 // 000 trying 360kB in 360kB
309 // 001 trying 360kB in 1.2MB
310 // 010 trying 1.2MB in 1.2MB
311 // 011 360kB in 360kB established
312 // 100 360kB in 1.2MB established
313 // 101 1.2MB in 1.2MB established
315 // 111 all other formats/drives
318 u8 config_data, media_state;
319 switch (GET_GLOBAL(FloppyTypes[drive])) {
322 config_data = 0x00; // 0000 0000
323 media_state = 0x25; // 0010 0101
326 // 1.2 MB 5.25" drive
327 config_data = 0x00; // 0000 0000
328 media_state = 0x25; // 0010 0101 // need double stepping??? (bit 5)
332 config_data = 0x00; // 0000 0000 ???
333 media_state = 0x17; // 0001 0111
336 // 1.44 MB 3.5" drive
337 config_data = 0x00; // 0000 0000
338 media_state = 0x17; // 0001 0111
341 // 2.88 MB 3.5" drive
342 config_data = 0xCC; // 1100 1100
343 media_state = 0xD7; // 1101 0111
346 // Extended floppy size uses special cmos setting
349 config_data = 0x00; // 0000 0000
350 media_state = 0x27; // 0010 0111
354 config_data = 0x00; // 0000 0000
355 media_state = 0x27; // 0010 0111
359 config_data = 0x00; // 0000 0000
360 media_state = 0x27; // 0010 0111
364 config_data = 0x00; // 0000 0000
365 media_state = 0x00; // 0000 0000
369 SET_BDA(floppy_last_data_rate, config_data);
370 SET_BDA(floppy_media_state[drive], media_state);
375 check_drive(struct bregs *regs, u8 drive)
377 // see if drive exists
378 if (drive > 1 || !GET_GLOBAL(FloppyTypes[drive])) {
379 floppy_ret(regs, DISK_RET_ETIMEOUT);
383 if ((GET_BDA(floppy_recalibration_status) & (1<<drive))
384 && (GET_BDA(floppy_media_state[drive]) & FMS_MEDIA_DRIVE_ESTABLISHED))
388 // Recalibrate drive.
389 floppy_drive_recal(drive);
392 int ret = floppy_media_sense(drive);
394 floppy_ret(regs, DISK_RET_EMEDIA);
401 /****************************************************************
402 * Floppy int13 handlers
403 ****************************************************************/
405 // diskette controller reset
407 floppy_1300(struct bregs *regs, u8 drive)
410 floppy_ret(regs, DISK_RET_EPARAM);
413 if (!GET_GLOBAL(FloppyTypes[drive])) {
414 floppy_ret(regs, DISK_RET_ETIMEOUT);
417 set_diskette_current_cyl(drive, 0); // current cylinder
418 floppy_ret(regs, DISK_RET_SUCCESS);
421 // Read Diskette Status
423 floppy_1301(struct bregs *regs, u8 drive)
425 u8 v = GET_BDA(floppy_last_status);
430 // Read Diskette Sectors
432 floppy_1302(struct bregs *regs, u8 drive)
434 if (check_drive(regs, drive))
437 u8 num_sectors = regs->al;
439 u8 sector = regs->cl;
442 if (head > 1 || sector == 0 || num_sectors == 0
443 || track > 79 || num_sectors > 72) {
444 floppy_ret(regs, DISK_RET_EPARAM);
448 // send read-normal-data command (9 bytes) to controller
450 data[0] = 0xe6; // e6: read normal data
451 data[1] = (head << 2) | drive; // HD DR1 DR2
455 data[5] = 2; // 512 byte sector size
456 data[6] = sector + num_sectors - 1; // last sector to read on track
457 data[7] = 0; // Gap length
458 data[8] = 0xff; // Gap length
460 int ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
464 if (data[0] & 0xc0) {
465 floppy_ret(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 regs->al = 0; // no sectors read
478 // Write Diskette Sectors
480 floppy_1303(struct bregs *regs, u8 drive)
482 if (check_drive(regs, drive))
485 u8 num_sectors = regs->al;
487 u8 sector = regs->cl;
490 if (head > 1 || sector == 0 || num_sectors == 0
491 || track > 79 || num_sectors > 72) {
492 floppy_ret(regs, DISK_RET_EPARAM);
496 // send write-normal-data command (9 bytes) to controller
498 data[0] = 0xc5; // c5: write normal data
499 data[1] = (head << 2) | drive; // HD DR1 DR2
503 data[5] = 2; // 512 byte sector size
504 data[6] = sector + num_sectors - 1; // last sector to write on track
505 data[7] = 0; // Gap length
506 data[8] = 0xff; // Gap length
508 int ret = floppy_cmd(regs, (num_sectors * 512) - 1, data, 9);
512 if (data[0] & 0xc0) {
514 floppy_ret(regs, DISK_RET_EWRITEPROTECT);
516 floppy_ret(regs, DISK_RET_ECONTROLLER);
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 regs->al = 0; // no sectors read
529 // Verify Diskette Sectors
531 floppy_1304(struct bregs *regs, u8 drive)
533 if (check_drive(regs, drive))
536 u8 num_sectors = regs->al;
538 u8 sector = regs->cl;
541 if (head > 1 || sector == 0 || num_sectors == 0
542 || track > 79 || num_sectors > 72) {
543 floppy_ret(regs, DISK_RET_EPARAM);
547 // ??? should track be new val from return_status[3] ?
548 set_diskette_current_cyl(drive, track);
549 // AL = number of sectors verified (same value as passed)
550 floppy_ret(regs, DISK_RET_SUCCESS);
553 regs->al = 0; // no sectors read
556 // format diskette track
558 floppy_1305(struct bregs *regs, u8 drive)
560 dprintf(3, "floppy f05\n");
562 if (check_drive(regs, drive))
565 u8 num_sectors = regs->al;
568 if (head > 1 || num_sectors == 0 || num_sectors > 18) {
569 floppy_ret(regs, DISK_RET_EPARAM);
573 // send format-track command (6 bytes) to controller
575 data[0] = 0x4d; // 4d: format track
576 data[1] = (head << 2) | drive; // HD DR1 DR2
577 data[2] = 2; // 512 byte sector size
578 data[3] = num_sectors; // number of sectors per track
579 data[4] = 0; // Gap length
580 data[5] = 0xf6; // Fill byte
582 int ret = floppy_cmd(regs, (num_sectors * 4) - 1, data, 6);
586 if (data[0] & 0xc0) {
588 floppy_ret(regs, DISK_RET_EWRITEPROTECT);
590 floppy_ret(regs, DISK_RET_ECONTROLLER);
594 set_diskette_current_cyl(drive, 0);
598 // read diskette drive parameters
600 floppy_1308(struct bregs *regs, u8 drive)
602 dprintf(3, "floppy f08\n");
605 regs->dx = GET_GLOBAL(FloppyCount);
615 u8 drive_type = GET_GLOBAL(FloppyTypes[drive]);
616 regs->bx = drive_type;
618 switch (drive_type) {
620 dprintf(1, "floppy: int13: bad floppy type\n");
624 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 #
630 case 2: // 1.2MB, 5.25"
631 regs->cx = 0x4f0f; // 80 tracks, 15 sectors
632 regs->dh = 1; // max head #
634 case 3: // 720KB, 3.5"
635 regs->cx = 0x4f09; // 80 tracks, 9 sectors
636 regs->dh = 1; // max head #
638 case 4: // 1.44MB, 3.5"
639 regs->cx = 0x4f12; // 80 tracks, 18 sectors
640 regs->dh = 1; // max head #
642 case 5: // 2.88MB, 3.5"
643 regs->cx = 0x4f24; // 80 tracks, 36 sectors
644 regs->dh = 1; // max head #
646 case 6: // 160k, 5.25"
647 regs->cx = 0x2708; // 40 tracks, 8 sectors
648 regs->dh = 0; // max head #
650 case 7: // 180k, 5.25"
651 regs->cx = 0x2709; // 40 tracks, 9 sectors
652 regs->dh = 0; // max head #
654 case 8: // 320k, 5.25"
655 regs->cx = 0x2708; // 40 tracks, 8 sectors
656 regs->dh = 1; // max head #
660 /* set es & di to point to 11 byte diskette param table in ROM */
662 regs->di = (u32)&diskette_param_table2;
663 /* disk status not changed upon success */
667 // read diskette drive type
669 floppy_1315(struct bregs *regs, u8 drive)
671 dprintf(6, "floppy f15\n");
674 regs->ah = 0; // only 2 drives supported
675 // set_diskette_ret_status here ???
678 u8 drive_type = GET_GLOBAL(FloppyTypes[drive]);
680 regs->ah = (drive_type != 0);
684 // get diskette change line status
686 floppy_1316(struct bregs *regs, u8 drive)
689 floppy_ret(regs, DISK_RET_EPARAM);
692 floppy_ret(regs, DISK_RET_ECHANGED);
696 floppy_13XX(struct bregs *regs, u8 drive)
698 floppy_ret(regs, DISK_RET_EPARAM);
702 floppy_13(struct bregs *regs, u8 drive)
704 if (! CONFIG_FLOPPY_SUPPORT) {
707 case 0x01: floppy_1301(regs, drive); break;
708 default: floppy_13XX(regs, drive); break;
713 case 0x00: floppy_1300(regs, drive); break;
714 case 0x01: floppy_1301(regs, drive); break;
715 case 0x02: floppy_1302(regs, drive); break;
716 case 0x03: floppy_1303(regs, drive); break;
717 case 0x04: floppy_1304(regs, drive); break;
718 case 0x05: floppy_1305(regs, drive); break;
719 case 0x08: floppy_1308(regs, drive); break;
720 case 0x15: floppy_1315(regs, drive); break;
721 case 0x16: floppy_1316(regs, drive); break;
722 default: floppy_13XX(regs, drive); break;
727 /****************************************************************
729 ****************************************************************/
731 // INT 0Eh Diskette Hardware ISR Entry Point
735 debug_isr(DEBUG_ISR_0e);
736 if (! CONFIG_FLOPPY_SUPPORT)
739 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
740 outb(0x08, PORT_FD_DATA); // sense interrupt status
741 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
745 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
747 // diskette interrupt has occurred
748 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
754 // Called from int08 handler.
758 if (! CONFIG_FLOPPY_SUPPORT)
761 // time to turn off drive(s)?
762 u8 fcount = GET_BDA(floppy_motor_counter);
765 SET_BDA(floppy_motor_counter, fcount);
768 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);