1 // 16bit code to access floppy drives.
3 // Copyright (C) 2008,2009 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
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 FLOPPY_SIZE_CODE 0x02 // 512 byte sectors
18 #define FLOPPY_DATALEN 0xff // Not used - because size code is 0x02
19 #define FLOPPY_MOTOR_TICKS 37 // ~2 seconds
20 #define FLOPPY_FILLBYTE 0xf6
21 #define FLOPPY_GAPLEN 0x1B
22 #define FLOPPY_FORMAT_GAPLEN 0x6c
24 // New diskette parameter table adding 3 parameters from IBM
25 // Since no provisions are made for multiple drive types, most
26 // values in this table are ignored. I set parameters for 1.44M
28 struct floppy_ext_dbt_s diskette_param_table2 VAR16VISIBLE = {
30 .specify1 = 0xAF, // step rate 12ms, head unload 240ms
31 .specify2 = 0x02, // head load time 4ms, DMA used
32 .shutoff_ticks = FLOPPY_MOTOR_TICKS, // ~2 seconds
33 .bps_code = FLOPPY_SIZE_CODE,
35 .interblock_len = FLOPPY_GAPLEN,
36 .data_len = FLOPPY_DATALEN,
37 .gap_len = FLOPPY_FORMAT_GAPLEN,
38 .fill_byte = FLOPPY_FILLBYTE,
39 .settle_time = 0x0F, // 15ms
40 .startup_time = 0x08, // 1 second
42 .max_track = 79, // maximum track
43 .data_rate = 0, // data transfer rate
44 .drive_type = 4, // drive type in cmos
47 // Since no provisions are made for multiple drive types, most
48 // values in this table are ignored. I set parameters for 1.44M
50 struct floppy_dbt_s diskette_param_table VAR16FIXED(0xefc7) = {
53 .shutoff_ticks = FLOPPY_MOTOR_TICKS,
54 .bps_code = FLOPPY_SIZE_CODE,
56 .interblock_len = FLOPPY_GAPLEN,
57 .data_len = FLOPPY_DATALEN,
58 .gap_len = FLOPPY_FORMAT_GAPLEN,
59 .fill_byte = FLOPPY_FILLBYTE,
70 struct floppyinfo_s FloppyInfo[] VAR16VISIBLE = {
72 { {0, 0, 0}, 0x00, 0x00},
73 // 1 - 360KB, 5.25" - 2 heads, 40 tracks, 9 sectors
74 { {2, 40, 9}, 0x00, 0x25},
75 // 2 - 1.2MB, 5.25" - 2 heads, 80 tracks, 15 sectors
76 { {2, 80, 15}, 0x00, 0x25},
77 // 3 - 720KB, 3.5" - 2 heads, 80 tracks, 9 sectors
78 { {2, 80, 9}, 0x00, 0x17},
79 // 4 - 1.44MB, 3.5" - 2 heads, 80 tracks, 18 sectors
80 { {2, 80, 18}, 0x00, 0x17},
81 // 5 - 2.88MB, 3.5" - 2 heads, 80 tracks, 36 sectors
82 { {2, 80, 36}, 0xCC, 0xD7},
83 // 6 - 160k, 5.25" - 1 heads, 40 tracks, 8 sectors
84 { {1, 40, 8}, 0x00, 0x27},
85 // 7 - 180k, 5.25" - 1 heads, 40 tracks, 9 sectors
86 { {1, 40, 9}, 0x00, 0x27},
87 // 8 - 320k, 5.25" - 2 heads, 40 tracks, 8 sectors
88 { {2, 40, 8}, 0x00, 0x27},
92 addFloppy(int floppyid, int ftype, int driver)
94 if (ftype <= 0 || ftype >= ARRAY_SIZE(FloppyInfo)) {
95 dprintf(1, "Bad floppy type %d\n", ftype);
99 int driveid = Drives.drivecount;
100 if (driveid >= ARRAY_SIZE(Drives.drives))
103 memset(&Drives.drives[driveid], 0, sizeof(Drives.drives[0]));
104 Drives.drives[driveid].cntl_id = floppyid;
105 Drives.drives[driveid].type = driver;
106 Drives.drives[driveid].blksize = DISK_SECTOR_SIZE;
107 Drives.drives[driveid].floppy_type = ftype;
108 Drives.drives[driveid].sectors = (u64)-1;
110 memcpy(&Drives.drives[driveid].lchs, &FloppyInfo[ftype].chs
111 , sizeof(FloppyInfo[ftype].chs));
113 map_floppy_drive(driveid);
118 describe_floppy(int driveid)
120 printf("drive %c", 'A' + Drives.drives[driveid].cntl_id);
128 dprintf(3, "init floppy drives\n");
130 if (CONFIG_COREBOOT) {
131 // XXX - disable floppies on coreboot for now.
133 u8 type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
135 addFloppy(0, type >> 4, DTYPE_FLOPPY);
137 addFloppy(1, type & 0x0f, DTYPE_FLOPPY);
140 outb(0x02, PORT_DMA1_MASK_REG);
142 enable_hwirq(6, entry_0e);
145 // Find a floppy type that matches a given image size.
147 find_floppy_type(u32 size)
150 for (i=1; i<ARRAY_SIZE(FloppyInfo); i++) {
151 struct chs_s *c = &FloppyInfo[i].chs;
152 if (c->cylinders * c->heads * c->spt * DISK_SECTOR_SIZE == size)
159 /****************************************************************
160 * Low-level floppy IO
161 ****************************************************************/
164 floppy_reset_controller()
167 u8 val8 = inb(PORT_FD_DOR);
168 outb(val8 & ~0x04, PORT_FD_DOR);
169 outb(val8 | 0x04, PORT_FD_DOR);
171 // Wait for controller to come out of reset
172 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
181 if (!GET_BDA(floppy_motor_counter)) {
185 v = GET_BDA(floppy_recalibration_status);
192 SET_BDA(floppy_recalibration_status, v);
197 floppy_prepare_controller(u8 floppyid)
199 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
201 // turn on motor of selected drive, DMA & int enabled, normal operation
202 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
208 outb(dor, PORT_FD_DOR);
210 // reset the disk motor timeout value of INT 08
211 SET_BDA(floppy_motor_counter, FLOPPY_MOTOR_TICKS);
213 // wait for drive readiness
214 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
222 floppy_pio(u8 *cmd, u8 cmdlen)
224 floppy_prepare_controller(cmd[1] & 1);
226 // send command to controller
228 for (i=0; i<cmdlen; i++)
229 outb(cmd[i], PORT_FD_DATA);
231 int ret = wait_floppy_irq();
233 floppy_reset_controller();
241 floppy_cmd(struct disk_op_s *op, u16 count, u8 *cmd, u8 cmdlen)
243 // es:bx = pointer to where to place information from diskette
244 u32 addr = (u32)op->buf_fl;
246 // check for 64K boundary overrun
248 u32 last_addr = addr + end;
249 if ((addr >> 16) != (last_addr >> 16))
250 return DISK_RET_EBOUNDARY;
252 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
255 mode_register = 0x46;
257 //DEBUGF("floppy dma c2\n");
258 outb(0x06, PORT_DMA1_MASK_REG);
259 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
260 outb(addr, PORT_DMA_ADDR_2);
261 outb(addr>>8, PORT_DMA_ADDR_2);
262 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
263 outb(end, PORT_DMA_CNT_2);
264 outb(end>>8, PORT_DMA_CNT_2);
266 // port 0b: DMA-1 Mode Register
267 // transfer type=write, channel 2
268 outb(mode_register, PORT_DMA1_MODE_REG);
270 // port 81: DMA-1 Page Register, channel 2
271 outb(addr>>16, PORT_DMA_PAGE_2);
273 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
275 int ret = floppy_pio(cmd, cmdlen);
277 return DISK_RET_ETIMEOUT;
279 // check port 3f4 for accessibility to status bytes
280 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
281 return DISK_RET_ECONTROLLER;
283 // read 7 return status bytes from controller
285 for (i=0; i<7; i++) {
286 u8 v = inb(PORT_FD_DATA);
288 SET_BDA(floppy_return_status[i], v);
291 return DISK_RET_SUCCESS;
295 /****************************************************************
297 ****************************************************************/
300 set_diskette_current_cyl(u8 floppyid, u8 cyl)
302 SET_BDA(floppy_track[floppyid], cyl);
306 floppy_drive_recal(u8 floppyid)
308 // send Recalibrate command (2 bytes) to controller
310 data[0] = 0x07; // 07: Recalibrate
311 data[1] = floppyid; // 0=drive0, 1=drive1
314 SETBITS_BDA(floppy_recalibration_status, 1<<floppyid);
315 set_diskette_current_cyl(floppyid, 0);
319 floppy_media_sense(u8 driveid)
321 // for now cheat and get drive type from CMOS,
322 // assume media is same as drive type
325 // Bitfields for diskette media control:
326 // Bit(s) Description (Table M0028)
327 // 7-6 last data rate set by controller
328 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
329 // 5-4 last diskette drive step rate selected
330 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
331 // 3-2 {data rate at start of operation}
335 // Bitfields for diskette drive media state:
336 // Bit(s) Description (Table M0030)
338 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
339 // 5 double stepping required (e.g. 360kB in 1.2MB)
340 // 4 media type established
341 // 3 drive capable of supporting 4MB media
342 // 2-0 on exit from BIOS, contains
343 // 000 trying 360kB in 360kB
344 // 001 trying 360kB in 1.2MB
345 // 010 trying 1.2MB in 1.2MB
346 // 011 360kB in 360kB established
347 // 100 360kB in 1.2MB established
348 // 101 1.2MB in 1.2MB established
350 // 111 all other formats/drives
352 u8 ftype = GET_GLOBAL(Drives.drives[driveid].floppy_type);
353 SET_BDA(floppy_last_data_rate, GET_GLOBAL(FloppyInfo[ftype].config_data));
354 u8 floppyid = GET_GLOBAL(Drives.drives[driveid].cntl_id);
355 SET_BDA(floppy_media_state[floppyid]
356 , GET_GLOBAL(FloppyInfo[ftype].media_state));
357 return DISK_RET_SUCCESS;
361 check_recal_drive(u8 driveid)
363 u8 floppyid = GET_GLOBAL(Drives.drives[driveid].cntl_id);
364 if ((GET_BDA(floppy_recalibration_status) & (1<<floppyid))
365 && (GET_BDA(floppy_media_state[floppyid]) & FMS_MEDIA_DRIVE_ESTABLISHED))
367 return DISK_RET_SUCCESS;
369 // Recalibrate drive.
370 floppy_drive_recal(floppyid);
373 return floppy_media_sense(driveid);
377 /****************************************************************
379 ****************************************************************/
382 lba2chs(struct disk_op_s *op, u8 *track, u8 *sector, u8 *head)
385 u8 driveid = op->driveid;
388 u16 nlspt = GET_GLOBAL(Drives.drives[driveid].lchs.spt);
389 *sector = tmp % nlspt;
392 u16 nlh = GET_GLOBAL(Drives.drives[driveid].lchs.heads);
399 // diskette controller reset
401 floppy_reset(struct disk_op_s *op)
403 u8 floppyid = GET_GLOBAL(Drives.drives[op->driveid].cntl_id);
404 set_diskette_current_cyl(floppyid, 0); // current cylinder
405 return DISK_RET_SUCCESS;
408 // Read Diskette Sectors
410 floppy_read(struct disk_op_s *op)
412 int res = check_recal_drive(op->driveid);
416 u8 track, sector, head;
417 lba2chs(op, &track, §or, &head);
419 // send read-normal-data command (9 bytes) to controller
420 u8 floppyid = GET_GLOBAL(Drives.drives[op->driveid].cntl_id);
422 data[0] = 0xe6; // e6: read normal data
423 data[1] = (head << 2) | floppyid; // HD DR1 DR2
427 data[5] = FLOPPY_SIZE_CODE;
428 data[6] = sector + op->count - 1; // last sector to read on track
429 data[7] = FLOPPY_GAPLEN;
430 data[8] = FLOPPY_DATALEN;
432 res = floppy_cmd(op, op->count * DISK_SECTOR_SIZE, data, 9);
436 if (data[0] & 0xc0) {
437 res = DISK_RET_ECONTROLLER;
441 // ??? should track be new val from return_status[3] ?
442 set_diskette_current_cyl(floppyid, track);
443 return DISK_RET_SUCCESS;
445 op->count = 0; // no sectors read
449 // Write Diskette Sectors
451 floppy_write(struct disk_op_s *op)
453 int res = check_recal_drive(op->driveid);
457 u8 track, sector, head;
458 lba2chs(op, &track, §or, &head);
460 // send write-normal-data command (9 bytes) to controller
461 u8 floppyid = GET_GLOBAL(Drives.drives[op->driveid].cntl_id);
463 data[0] = 0xc5; // c5: write normal data
464 data[1] = (head << 2) | floppyid; // HD DR1 DR2
468 data[5] = FLOPPY_SIZE_CODE;
469 data[6] = sector + op->count - 1; // last sector to write on track
470 data[7] = FLOPPY_GAPLEN;
471 data[8] = FLOPPY_DATALEN;
473 res = floppy_cmd(op, op->count * DISK_SECTOR_SIZE, data, 9);
477 if (data[0] & 0xc0) {
479 res = DISK_RET_EWRITEPROTECT;
481 res = DISK_RET_ECONTROLLER;
485 // ??? should track be new val from return_status[3] ?
486 set_diskette_current_cyl(floppyid, track);
487 return DISK_RET_SUCCESS;
489 op->count = 0; // no sectors read
493 // Verify Diskette Sectors
495 floppy_verify(struct disk_op_s *op)
497 int res = check_recal_drive(op->driveid);
501 u8 track, sector, head;
502 lba2chs(op, &track, §or, &head);
504 // ??? should track be new val from return_status[3] ?
505 u8 floppyid = GET_GLOBAL(Drives.drives[op->driveid].cntl_id);
506 set_diskette_current_cyl(floppyid, track);
507 return DISK_RET_SUCCESS;
509 op->count = 0; // no sectors read
513 // format diskette track
515 floppy_format(struct disk_op_s *op)
517 int ret = check_recal_drive(op->driveid);
523 // send format-track command (6 bytes) to controller
524 u8 floppyid = GET_GLOBAL(Drives.drives[op->driveid].cntl_id);
526 data[0] = 0x4d; // 4d: format track
527 data[1] = (head << 2) | floppyid; // HD DR1 DR2
528 data[2] = FLOPPY_SIZE_CODE;
529 data[3] = op->count; // number of sectors per track
530 data[4] = FLOPPY_FORMAT_GAPLEN;
531 data[5] = FLOPPY_FILLBYTE;
533 ret = floppy_cmd(op, op->count * 4, data, 6);
537 if (data[0] & 0xc0) {
539 return DISK_RET_EWRITEPROTECT;
540 return DISK_RET_ECONTROLLER;
543 set_diskette_current_cyl(floppyid, 0);
544 return DISK_RET_SUCCESS;
548 process_floppy_op(struct disk_op_s *op)
553 switch (op->command) {
555 return floppy_reset(op);
557 return floppy_read(op);
559 return floppy_write(op);
561 return floppy_verify(op);
563 return floppy_format(op);
566 return DISK_RET_EPARAM;
571 /****************************************************************
573 ****************************************************************/
575 // INT 0Eh Diskette Hardware ISR Entry Point
579 debug_isr(DEBUG_ISR_0e);
583 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
584 outb(0x08, PORT_FD_DATA); // sense interrupt status
585 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
589 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
591 // diskette interrupt has occurred
592 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
598 // Called from int08 handler.
605 // time to turn off drive(s)?
606 u8 fcount = GET_BDA(floppy_motor_counter);
609 SET_BDA(floppy_motor_counter, fcount);
612 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);