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" // wait_irq
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 struct drive_s *drive_g = allocDrive();
102 drive_g->cntl_id = floppyid;
103 drive_g->type = driver;
104 drive_g->blksize = DISK_SECTOR_SIZE;
105 drive_g->floppy_type = ftype;
106 drive_g->sectors = (u64)-1;
108 memcpy(&drive_g->lchs, &FloppyInfo[ftype].chs
109 , sizeof(FloppyInfo[ftype].chs));
111 map_floppy_drive(drive_g);
116 describe_floppy(struct drive_s *drive_g)
118 printf("drive %c", 'A' + drive_g->cntl_id);
126 dprintf(3, "init floppy drives\n");
128 if (CONFIG_COREBOOT) {
129 // XXX - disable floppies on coreboot for now.
131 u8 type = inb_cmos(CMOS_FLOPPY_DRIVE_TYPE);
133 addFloppy(0, type >> 4, DTYPE_FLOPPY);
135 addFloppy(1, type & 0x0f, DTYPE_FLOPPY);
138 outb(0x02, PORT_DMA1_MASK_REG);
140 enable_hwirq(6, entry_0e);
143 // Find a floppy type that matches a given image size.
145 find_floppy_type(u32 size)
148 for (i=1; i<ARRAY_SIZE(FloppyInfo); i++) {
149 struct chs_s *c = &FloppyInfo[i].chs;
150 if (c->cylinders * c->heads * c->spt * DISK_SECTOR_SIZE == size)
157 /****************************************************************
158 * Low-level floppy IO
159 ****************************************************************/
162 floppy_reset_controller(void)
165 u8 val8 = inb(PORT_FD_DOR);
166 outb(val8 & ~0x04, PORT_FD_DOR);
167 outb(val8 | 0x04, PORT_FD_DOR);
169 // Wait for controller to come out of reset
170 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
175 wait_floppy_irq(void)
180 if (!GET_BDA(floppy_motor_counter))
182 v = GET_BDA(floppy_recalibration_status);
185 // Could use wait_irq() here, but that causes issues on
186 // bochs, so use yield() instead.
191 SET_BDA(floppy_recalibration_status, v);
196 floppy_prepare_controller(u8 floppyid)
198 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
200 // turn on motor of selected drive, DMA & int enabled, normal operation
201 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
207 outb(dor, PORT_FD_DOR);
209 // reset the disk motor timeout value of INT 08
210 SET_BDA(floppy_motor_counter, FLOPPY_MOTOR_TICKS);
212 // wait for drive readiness
213 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
221 floppy_pio(u8 *cmd, u8 cmdlen)
223 floppy_prepare_controller(cmd[1] & 1);
225 // send command to controller
227 for (i=0; i<cmdlen; i++)
228 outb(cmd[i], PORT_FD_DATA);
230 int ret = wait_floppy_irq();
232 floppy_reset_controller();
240 floppy_cmd(struct disk_op_s *op, u16 count, u8 *cmd, u8 cmdlen)
242 // es:bx = pointer to where to place information from diskette
243 u32 addr = (u32)op->buf_fl;
245 // check for 64K boundary overrun
247 u32 last_addr = addr + end;
248 if ((addr >> 16) != (last_addr >> 16))
249 return DISK_RET_EBOUNDARY;
251 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
254 mode_register = 0x46;
256 //DEBUGF("floppy dma c2\n");
257 outb(0x06, PORT_DMA1_MASK_REG);
258 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
259 outb(addr, PORT_DMA_ADDR_2);
260 outb(addr>>8, PORT_DMA_ADDR_2);
261 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
262 outb(end, PORT_DMA_CNT_2);
263 outb(end>>8, PORT_DMA_CNT_2);
265 // port 0b: DMA-1 Mode Register
266 // transfer type=write, channel 2
267 outb(mode_register, PORT_DMA1_MODE_REG);
269 // port 81: DMA-1 Page Register, channel 2
270 outb(addr>>16, PORT_DMA_PAGE_2);
272 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
274 int ret = floppy_pio(cmd, cmdlen);
276 return DISK_RET_ETIMEOUT;
278 // check port 3f4 for accessibility to status bytes
279 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
280 return DISK_RET_ECONTROLLER;
282 // read 7 return status bytes from controller
284 for (i=0; i<7; i++) {
285 u8 v = inb(PORT_FD_DATA);
287 SET_BDA(floppy_return_status[i], v);
290 return DISK_RET_SUCCESS;
294 /****************************************************************
296 ****************************************************************/
299 set_diskette_current_cyl(u8 floppyid, u8 cyl)
301 SET_BDA(floppy_track[floppyid], cyl);
305 floppy_drive_recal(u8 floppyid)
307 // send Recalibrate command (2 bytes) to controller
309 data[0] = 0x07; // 07: Recalibrate
310 data[1] = floppyid; // 0=drive0, 1=drive1
313 SETBITS_BDA(floppy_recalibration_status, 1<<floppyid);
314 set_diskette_current_cyl(floppyid, 0);
318 floppy_media_sense(struct drive_s *drive_g)
320 // for now cheat and get drive type from CMOS,
321 // assume media is same as drive type
324 // Bitfields for diskette media control:
325 // Bit(s) Description (Table M0028)
326 // 7-6 last data rate set by controller
327 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
328 // 5-4 last diskette drive step rate selected
329 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
330 // 3-2 {data rate at start of operation}
334 // Bitfields for diskette drive media state:
335 // Bit(s) Description (Table M0030)
337 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
338 // 5 double stepping required (e.g. 360kB in 1.2MB)
339 // 4 media type established
340 // 3 drive capable of supporting 4MB media
341 // 2-0 on exit from BIOS, contains
342 // 000 trying 360kB in 360kB
343 // 001 trying 360kB in 1.2MB
344 // 010 trying 1.2MB in 1.2MB
345 // 011 360kB in 360kB established
346 // 100 360kB in 1.2MB established
347 // 101 1.2MB in 1.2MB established
349 // 111 all other formats/drives
351 u8 ftype = GET_GLOBAL(drive_g->floppy_type);
352 SET_BDA(floppy_last_data_rate, GET_GLOBAL(FloppyInfo[ftype].config_data));
353 u8 floppyid = GET_GLOBAL(drive_g->cntl_id);
354 SET_BDA(floppy_media_state[floppyid]
355 , GET_GLOBAL(FloppyInfo[ftype].media_state));
356 return DISK_RET_SUCCESS;
360 check_recal_drive(struct drive_s *drive_g)
362 u8 floppyid = GET_GLOBAL(drive_g->cntl_id);
363 if ((GET_BDA(floppy_recalibration_status) & (1<<floppyid))
364 && (GET_BDA(floppy_media_state[floppyid]) & FMS_MEDIA_DRIVE_ESTABLISHED))
366 return DISK_RET_SUCCESS;
368 // Recalibrate drive.
369 floppy_drive_recal(floppyid);
372 return floppy_media_sense(drive_g);
376 /****************************************************************
378 ****************************************************************/
381 lba2chs(struct disk_op_s *op, u8 *track, u8 *sector, u8 *head)
386 u16 nlspt = GET_GLOBAL(op->drive_g->lchs.spt);
387 *sector = tmp % nlspt;
390 u16 nlh = GET_GLOBAL(op->drive_g->lchs.heads);
397 // diskette controller reset
399 floppy_reset(struct disk_op_s *op)
401 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
402 set_diskette_current_cyl(floppyid, 0); // current cylinder
403 return DISK_RET_SUCCESS;
406 // Read Diskette Sectors
408 floppy_read(struct disk_op_s *op)
410 int res = check_recal_drive(op->drive_g);
414 u8 track, sector, head;
415 lba2chs(op, &track, §or, &head);
417 // send read-normal-data command (9 bytes) to controller
418 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
420 data[0] = 0xe6; // e6: read normal data
421 data[1] = (head << 2) | floppyid; // HD DR1 DR2
425 data[5] = FLOPPY_SIZE_CODE;
426 data[6] = sector + op->count - 1; // last sector to read on track
427 data[7] = FLOPPY_GAPLEN;
428 data[8] = FLOPPY_DATALEN;
430 res = floppy_cmd(op, op->count * DISK_SECTOR_SIZE, data, 9);
434 if (data[0] & 0xc0) {
435 res = DISK_RET_ECONTROLLER;
439 // ??? should track be new val from return_status[3] ?
440 set_diskette_current_cyl(floppyid, track);
441 return DISK_RET_SUCCESS;
443 op->count = 0; // no sectors read
447 // Write Diskette Sectors
449 floppy_write(struct disk_op_s *op)
451 int res = check_recal_drive(op->drive_g);
455 u8 track, sector, head;
456 lba2chs(op, &track, §or, &head);
458 // send write-normal-data command (9 bytes) to controller
459 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
461 data[0] = 0xc5; // c5: write normal data
462 data[1] = (head << 2) | floppyid; // HD DR1 DR2
466 data[5] = FLOPPY_SIZE_CODE;
467 data[6] = sector + op->count - 1; // last sector to write on track
468 data[7] = FLOPPY_GAPLEN;
469 data[8] = FLOPPY_DATALEN;
471 res = floppy_cmd(op, op->count * DISK_SECTOR_SIZE, data, 9);
475 if (data[0] & 0xc0) {
477 res = DISK_RET_EWRITEPROTECT;
479 res = DISK_RET_ECONTROLLER;
483 // ??? should track be new val from return_status[3] ?
484 set_diskette_current_cyl(floppyid, track);
485 return DISK_RET_SUCCESS;
487 op->count = 0; // no sectors read
491 // Verify Diskette Sectors
493 floppy_verify(struct disk_op_s *op)
495 int res = check_recal_drive(op->drive_g);
499 u8 track, sector, head;
500 lba2chs(op, &track, §or, &head);
502 // ??? should track be new val from return_status[3] ?
503 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
504 set_diskette_current_cyl(floppyid, track);
505 return DISK_RET_SUCCESS;
507 op->count = 0; // no sectors read
511 // format diskette track
513 floppy_format(struct disk_op_s *op)
515 int ret = check_recal_drive(op->drive_g);
521 // send format-track command (6 bytes) to controller
522 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
524 data[0] = 0x4d; // 4d: format track
525 data[1] = (head << 2) | floppyid; // HD DR1 DR2
526 data[2] = FLOPPY_SIZE_CODE;
527 data[3] = op->count; // number of sectors per track
528 data[4] = FLOPPY_FORMAT_GAPLEN;
529 data[5] = FLOPPY_FILLBYTE;
531 ret = floppy_cmd(op, op->count * 4, data, 6);
535 if (data[0] & 0xc0) {
537 return DISK_RET_EWRITEPROTECT;
538 return DISK_RET_ECONTROLLER;
541 set_diskette_current_cyl(floppyid, 0);
542 return DISK_RET_SUCCESS;
546 process_floppy_op(struct disk_op_s *op)
551 switch (op->command) {
553 return floppy_reset(op);
555 return floppy_read(op);
557 return floppy_write(op);
559 return floppy_verify(op);
561 return floppy_format(op);
564 return DISK_RET_EPARAM;
569 /****************************************************************
571 ****************************************************************/
573 // INT 0Eh Diskette Hardware ISR Entry Point
577 debug_isr(DEBUG_ISR_0e);
581 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
582 outb(0x08, PORT_FD_DATA); // sense interrupt status
583 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
587 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
589 // diskette interrupt has occurred
590 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
596 // Called from int08 handler.
603 // time to turn off drive(s)?
604 u8 fcount = GET_BDA(floppy_motor_counter);
607 SET_BDA(floppy_motor_counter, fcount);
610 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);