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 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()
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)
179 if (!GET_BDA(floppy_motor_counter)) {
183 v = GET_BDA(floppy_recalibration_status);
190 SET_BDA(floppy_recalibration_status, v);
195 floppy_prepare_controller(u8 floppyid)
197 CLEARBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
199 // turn on motor of selected drive, DMA & int enabled, normal operation
200 u8 prev_reset = inb(PORT_FD_DOR) & 0x04;
206 outb(dor, PORT_FD_DOR);
208 // reset the disk motor timeout value of INT 08
209 SET_BDA(floppy_motor_counter, FLOPPY_MOTOR_TICKS);
211 // wait for drive readiness
212 while ((inb(PORT_FD_STATUS) & 0xc0) != 0x80)
220 floppy_pio(u8 *cmd, u8 cmdlen)
222 floppy_prepare_controller(cmd[1] & 1);
224 // send command to controller
226 for (i=0; i<cmdlen; i++)
227 outb(cmd[i], PORT_FD_DATA);
229 int ret = wait_floppy_irq();
231 floppy_reset_controller();
239 floppy_cmd(struct disk_op_s *op, u16 count, u8 *cmd, u8 cmdlen)
241 // es:bx = pointer to where to place information from diskette
242 u32 addr = (u32)op->buf_fl;
244 // check for 64K boundary overrun
246 u32 last_addr = addr + end;
247 if ((addr >> 16) != (last_addr >> 16))
248 return DISK_RET_EBOUNDARY;
250 u8 mode_register = 0x4a; // single mode, increment, autoinit disable,
253 mode_register = 0x46;
255 //DEBUGF("floppy dma c2\n");
256 outb(0x06, PORT_DMA1_MASK_REG);
257 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
258 outb(addr, PORT_DMA_ADDR_2);
259 outb(addr>>8, PORT_DMA_ADDR_2);
260 outb(0x00, PORT_DMA1_CLEAR_FF_REG); // clear flip-flop
261 outb(end, PORT_DMA_CNT_2);
262 outb(end>>8, PORT_DMA_CNT_2);
264 // port 0b: DMA-1 Mode Register
265 // transfer type=write, channel 2
266 outb(mode_register, PORT_DMA1_MODE_REG);
268 // port 81: DMA-1 Page Register, channel 2
269 outb(addr>>16, PORT_DMA_PAGE_2);
271 outb(0x02, PORT_DMA1_MASK_REG); // unmask channel 2
273 int ret = floppy_pio(cmd, cmdlen);
275 return DISK_RET_ETIMEOUT;
277 // check port 3f4 for accessibility to status bytes
278 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
279 return DISK_RET_ECONTROLLER;
281 // read 7 return status bytes from controller
283 for (i=0; i<7; i++) {
284 u8 v = inb(PORT_FD_DATA);
286 SET_BDA(floppy_return_status[i], v);
289 return DISK_RET_SUCCESS;
293 /****************************************************************
295 ****************************************************************/
298 set_diskette_current_cyl(u8 floppyid, u8 cyl)
300 SET_BDA(floppy_track[floppyid], cyl);
304 floppy_drive_recal(u8 floppyid)
306 // send Recalibrate command (2 bytes) to controller
308 data[0] = 0x07; // 07: Recalibrate
309 data[1] = floppyid; // 0=drive0, 1=drive1
312 SETBITS_BDA(floppy_recalibration_status, 1<<floppyid);
313 set_diskette_current_cyl(floppyid, 0);
317 floppy_media_sense(struct drive_s *drive_g)
319 // for now cheat and get drive type from CMOS,
320 // assume media is same as drive type
323 // Bitfields for diskette media control:
324 // Bit(s) Description (Table M0028)
325 // 7-6 last data rate set by controller
326 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
327 // 5-4 last diskette drive step rate selected
328 // 00=0Ch, 01=0Dh, 10=0Eh, 11=0Ah
329 // 3-2 {data rate at start of operation}
333 // Bitfields for diskette drive media state:
334 // Bit(s) Description (Table M0030)
336 // 00=500kbps, 01=300kbps, 10=250kbps, 11=1Mbps
337 // 5 double stepping required (e.g. 360kB in 1.2MB)
338 // 4 media type established
339 // 3 drive capable of supporting 4MB media
340 // 2-0 on exit from BIOS, contains
341 // 000 trying 360kB in 360kB
342 // 001 trying 360kB in 1.2MB
343 // 010 trying 1.2MB in 1.2MB
344 // 011 360kB in 360kB established
345 // 100 360kB in 1.2MB established
346 // 101 1.2MB in 1.2MB established
348 // 111 all other formats/drives
350 u8 ftype = GET_GLOBAL(drive_g->floppy_type);
351 SET_BDA(floppy_last_data_rate, GET_GLOBAL(FloppyInfo[ftype].config_data));
352 u8 floppyid = GET_GLOBAL(drive_g->cntl_id);
353 SET_BDA(floppy_media_state[floppyid]
354 , GET_GLOBAL(FloppyInfo[ftype].media_state));
355 return DISK_RET_SUCCESS;
359 check_recal_drive(struct drive_s *drive_g)
361 u8 floppyid = GET_GLOBAL(drive_g->cntl_id);
362 if ((GET_BDA(floppy_recalibration_status) & (1<<floppyid))
363 && (GET_BDA(floppy_media_state[floppyid]) & FMS_MEDIA_DRIVE_ESTABLISHED))
365 return DISK_RET_SUCCESS;
367 // Recalibrate drive.
368 floppy_drive_recal(floppyid);
371 return floppy_media_sense(drive_g);
375 /****************************************************************
377 ****************************************************************/
380 lba2chs(struct disk_op_s *op, u8 *track, u8 *sector, u8 *head)
385 u16 nlspt = GET_GLOBAL(op->drive_g->lchs.spt);
386 *sector = tmp % nlspt;
389 u16 nlh = GET_GLOBAL(op->drive_g->lchs.heads);
396 // diskette controller reset
398 floppy_reset(struct disk_op_s *op)
400 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
401 set_diskette_current_cyl(floppyid, 0); // current cylinder
402 return DISK_RET_SUCCESS;
405 // Read Diskette Sectors
407 floppy_read(struct disk_op_s *op)
409 int res = check_recal_drive(op->drive_g);
413 u8 track, sector, head;
414 lba2chs(op, &track, §or, &head);
416 // send read-normal-data command (9 bytes) to controller
417 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
419 data[0] = 0xe6; // e6: read normal data
420 data[1] = (head << 2) | floppyid; // HD DR1 DR2
424 data[5] = FLOPPY_SIZE_CODE;
425 data[6] = sector + op->count - 1; // last sector to read on track
426 data[7] = FLOPPY_GAPLEN;
427 data[8] = FLOPPY_DATALEN;
429 res = floppy_cmd(op, op->count * DISK_SECTOR_SIZE, data, 9);
433 if (data[0] & 0xc0) {
434 res = DISK_RET_ECONTROLLER;
438 // ??? should track be new val from return_status[3] ?
439 set_diskette_current_cyl(floppyid, track);
440 return DISK_RET_SUCCESS;
442 op->count = 0; // no sectors read
446 // Write Diskette Sectors
448 floppy_write(struct disk_op_s *op)
450 int res = check_recal_drive(op->drive_g);
454 u8 track, sector, head;
455 lba2chs(op, &track, §or, &head);
457 // send write-normal-data command (9 bytes) to controller
458 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
460 data[0] = 0xc5; // c5: write normal data
461 data[1] = (head << 2) | floppyid; // HD DR1 DR2
465 data[5] = FLOPPY_SIZE_CODE;
466 data[6] = sector + op->count - 1; // last sector to write on track
467 data[7] = FLOPPY_GAPLEN;
468 data[8] = FLOPPY_DATALEN;
470 res = floppy_cmd(op, op->count * DISK_SECTOR_SIZE, data, 9);
474 if (data[0] & 0xc0) {
476 res = DISK_RET_EWRITEPROTECT;
478 res = DISK_RET_ECONTROLLER;
482 // ??? should track be new val from return_status[3] ?
483 set_diskette_current_cyl(floppyid, track);
484 return DISK_RET_SUCCESS;
486 op->count = 0; // no sectors read
490 // Verify Diskette Sectors
492 floppy_verify(struct disk_op_s *op)
494 int res = check_recal_drive(op->drive_g);
498 u8 track, sector, head;
499 lba2chs(op, &track, §or, &head);
501 // ??? should track be new val from return_status[3] ?
502 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
503 set_diskette_current_cyl(floppyid, track);
504 return DISK_RET_SUCCESS;
506 op->count = 0; // no sectors read
510 // format diskette track
512 floppy_format(struct disk_op_s *op)
514 int ret = check_recal_drive(op->drive_g);
520 // send format-track command (6 bytes) to controller
521 u8 floppyid = GET_GLOBAL(op->drive_g->cntl_id);
523 data[0] = 0x4d; // 4d: format track
524 data[1] = (head << 2) | floppyid; // HD DR1 DR2
525 data[2] = FLOPPY_SIZE_CODE;
526 data[3] = op->count; // number of sectors per track
527 data[4] = FLOPPY_FORMAT_GAPLEN;
528 data[5] = FLOPPY_FILLBYTE;
530 ret = floppy_cmd(op, op->count * 4, data, 6);
534 if (data[0] & 0xc0) {
536 return DISK_RET_EWRITEPROTECT;
537 return DISK_RET_ECONTROLLER;
540 set_diskette_current_cyl(floppyid, 0);
541 return DISK_RET_SUCCESS;
545 process_floppy_op(struct disk_op_s *op)
550 switch (op->command) {
552 return floppy_reset(op);
554 return floppy_read(op);
556 return floppy_write(op);
558 return floppy_verify(op);
560 return floppy_format(op);
563 return DISK_RET_EPARAM;
568 /****************************************************************
570 ****************************************************************/
572 // INT 0Eh Diskette Hardware ISR Entry Point
576 debug_isr(DEBUG_ISR_0e);
580 if ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0) {
581 outb(0x08, PORT_FD_DATA); // sense interrupt status
582 while ((inb(PORT_FD_STATUS) & 0xc0) != 0xc0)
586 } while ((inb(PORT_FD_STATUS) & 0xc0) == 0xc0);
588 // diskette interrupt has occurred
589 SETBITS_BDA(floppy_recalibration_status, FRS_TIMEOUT);
595 // Called from int08 handler.
602 // time to turn off drive(s)?
603 u8 fcount = GET_BDA(floppy_motor_counter);
606 SET_BDA(floppy_motor_counter, fcount);
609 outb(inb(PORT_FD_DOR) & 0xcf, PORT_FD_DOR);