xref: /openbmc/qemu/hw/block/fdc.c (revision e3ae2bbf)
1 /*
2  * QEMU Floppy disk emulator (Intel 82078)
3  *
4  * Copyright (c) 2003, 2007 Jocelyn Mayer
5  * Copyright (c) 2008 Hervé Poussineau
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 /*
26  * The controller is used in Sun4m systems in a slightly different
27  * way. There are changes in DOR register and DMA is not available.
28  */
29 
30 #include "qemu/osdep.h"
31 #include "hw/block/fdc.h"
32 #include "qapi/error.h"
33 #include "qemu/error-report.h"
34 #include "qemu/timer.h"
35 #include "hw/irq.h"
36 #include "hw/isa/isa.h"
37 #include "hw/qdev-properties.h"
38 #include "hw/qdev-properties-system.h"
39 #include "migration/vmstate.h"
40 #include "hw/block/block.h"
41 #include "sysemu/block-backend.h"
42 #include "sysemu/blockdev.h"
43 #include "sysemu/sysemu.h"
44 #include "qemu/log.h"
45 #include "qemu/main-loop.h"
46 #include "qemu/module.h"
47 #include "trace.h"
48 #include "qom/object.h"
49 #include "fdc-internal.h"
50 
51 /********************************************************/
52 /* debug Floppy devices */
53 
54 #define DEBUG_FLOPPY 0
55 
56 #define FLOPPY_DPRINTF(fmt, ...)                                \
57     do {                                                        \
58         if (DEBUG_FLOPPY) {                                     \
59             fprintf(stderr, "FLOPPY: " fmt , ## __VA_ARGS__);   \
60         }                                                       \
61     } while (0)
62 
63 
64 /* Anonymous BlockBackend for empty drive */
65 static BlockBackend *blk_create_empty_drive(void)
66 {
67     return blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL);
68 }
69 
70 /********************************************************/
71 /* qdev floppy bus                                      */
72 
73 #define TYPE_FLOPPY_BUS "floppy-bus"
74 OBJECT_DECLARE_SIMPLE_TYPE(FloppyBus, FLOPPY_BUS)
75 
76 static FDrive *get_drv(FDCtrl *fdctrl, int unit);
77 
78 static const TypeInfo floppy_bus_info = {
79     .name = TYPE_FLOPPY_BUS,
80     .parent = TYPE_BUS,
81     .instance_size = sizeof(FloppyBus),
82 };
83 
84 static void floppy_bus_create(FDCtrl *fdc, FloppyBus *bus, DeviceState *dev)
85 {
86     qbus_init(bus, sizeof(FloppyBus), TYPE_FLOPPY_BUS, dev, NULL);
87     bus->fdc = fdc;
88 }
89 
90 
91 /********************************************************/
92 /* Floppy drive emulation                               */
93 
94 /* In many cases, the total sector size of a format is enough to uniquely
95  * identify it. However, there are some total sector collisions between
96  * formats of different physical size, and these are noted below by
97  * highlighting the total sector size for entries with collisions. */
98 const FDFormat fd_formats[] = {
99     /* First entry is default format */
100     /* 1.44 MB 3"1/2 floppy disks */
101     { FLOPPY_DRIVE_TYPE_144, 18, 80, 1, FDRIVE_RATE_500K, }, /* 3.5" 2880 */
102     { FLOPPY_DRIVE_TYPE_144, 20, 80, 1, FDRIVE_RATE_500K, }, /* 3.5" 3200 */
103     { FLOPPY_DRIVE_TYPE_144, 21, 80, 1, FDRIVE_RATE_500K, },
104     { FLOPPY_DRIVE_TYPE_144, 21, 82, 1, FDRIVE_RATE_500K, },
105     { FLOPPY_DRIVE_TYPE_144, 21, 83, 1, FDRIVE_RATE_500K, },
106     { FLOPPY_DRIVE_TYPE_144, 22, 80, 1, FDRIVE_RATE_500K, },
107     { FLOPPY_DRIVE_TYPE_144, 23, 80, 1, FDRIVE_RATE_500K, },
108     { FLOPPY_DRIVE_TYPE_144, 24, 80, 1, FDRIVE_RATE_500K, },
109     /* 2.88 MB 3"1/2 floppy disks */
110     { FLOPPY_DRIVE_TYPE_288, 36, 80, 1, FDRIVE_RATE_1M, },
111     { FLOPPY_DRIVE_TYPE_288, 39, 80, 1, FDRIVE_RATE_1M, },
112     { FLOPPY_DRIVE_TYPE_288, 40, 80, 1, FDRIVE_RATE_1M, },
113     { FLOPPY_DRIVE_TYPE_288, 44, 80, 1, FDRIVE_RATE_1M, },
114     { FLOPPY_DRIVE_TYPE_288, 48, 80, 1, FDRIVE_RATE_1M, },
115     /* 720 kB 3"1/2 floppy disks */
116     { FLOPPY_DRIVE_TYPE_144,  9, 80, 1, FDRIVE_RATE_250K, }, /* 3.5" 1440 */
117     { FLOPPY_DRIVE_TYPE_144, 10, 80, 1, FDRIVE_RATE_250K, },
118     { FLOPPY_DRIVE_TYPE_144, 10, 82, 1, FDRIVE_RATE_250K, },
119     { FLOPPY_DRIVE_TYPE_144, 10, 83, 1, FDRIVE_RATE_250K, },
120     { FLOPPY_DRIVE_TYPE_144, 13, 80, 1, FDRIVE_RATE_250K, },
121     { FLOPPY_DRIVE_TYPE_144, 14, 80, 1, FDRIVE_RATE_250K, },
122     /* 1.2 MB 5"1/4 floppy disks */
123     { FLOPPY_DRIVE_TYPE_120, 15, 80, 1, FDRIVE_RATE_500K, },
124     { FLOPPY_DRIVE_TYPE_120, 18, 80, 1, FDRIVE_RATE_500K, }, /* 5.25" 2880 */
125     { FLOPPY_DRIVE_TYPE_120, 18, 82, 1, FDRIVE_RATE_500K, },
126     { FLOPPY_DRIVE_TYPE_120, 18, 83, 1, FDRIVE_RATE_500K, },
127     { FLOPPY_DRIVE_TYPE_120, 20, 80, 1, FDRIVE_RATE_500K, }, /* 5.25" 3200 */
128     /* 720 kB 5"1/4 floppy disks */
129     { FLOPPY_DRIVE_TYPE_120,  9, 80, 1, FDRIVE_RATE_250K, }, /* 5.25" 1440 */
130     { FLOPPY_DRIVE_TYPE_120, 11, 80, 1, FDRIVE_RATE_250K, },
131     /* 360 kB 5"1/4 floppy disks */
132     { FLOPPY_DRIVE_TYPE_120,  9, 40, 1, FDRIVE_RATE_300K, }, /* 5.25" 720 */
133     { FLOPPY_DRIVE_TYPE_120,  9, 40, 0, FDRIVE_RATE_300K, },
134     { FLOPPY_DRIVE_TYPE_120, 10, 41, 1, FDRIVE_RATE_300K, },
135     { FLOPPY_DRIVE_TYPE_120, 10, 42, 1, FDRIVE_RATE_300K, },
136     /* 320 kB 5"1/4 floppy disks */
137     { FLOPPY_DRIVE_TYPE_120,  8, 40, 1, FDRIVE_RATE_250K, },
138     { FLOPPY_DRIVE_TYPE_120,  8, 40, 0, FDRIVE_RATE_250K, },
139     /* 360 kB must match 5"1/4 better than 3"1/2... */
140     { FLOPPY_DRIVE_TYPE_144,  9, 80, 0, FDRIVE_RATE_250K, }, /* 3.5" 720 */
141     /* end */
142     { FLOPPY_DRIVE_TYPE_NONE, -1, -1, 0, 0, },
143 };
144 
145 static FDriveSize drive_size(FloppyDriveType drive)
146 {
147     switch (drive) {
148     case FLOPPY_DRIVE_TYPE_120:
149         return FDRIVE_SIZE_525;
150     case FLOPPY_DRIVE_TYPE_144:
151     case FLOPPY_DRIVE_TYPE_288:
152         return FDRIVE_SIZE_350;
153     default:
154         return FDRIVE_SIZE_UNKNOWN;
155     }
156 }
157 
158 #define GET_CUR_DRV(fdctrl) ((fdctrl)->cur_drv)
159 #define SET_CUR_DRV(fdctrl, drive) ((fdctrl)->cur_drv = (drive))
160 
161 /* Will always be a fixed parameter for us */
162 #define FD_SECTOR_LEN          512
163 #define FD_SECTOR_SC           2   /* Sector size code */
164 #define FD_RESET_SENSEI_COUNT  4   /* Number of sense interrupts on RESET */
165 
166 
167 static FloppyDriveType get_fallback_drive_type(FDrive *drv);
168 
169 /* Hack: FD_SEEK is expected to work on empty drives. However, QEMU
170  * currently goes through some pains to keep seeks within the bounds
171  * established by last_sect and max_track. Correcting this is difficult,
172  * as refactoring FDC code tends to expose nasty bugs in the Linux kernel.
173  *
174  * For now: allow empty drives to have large bounds so we can seek around,
175  * with the understanding that when a diskette is inserted, the bounds will
176  * properly tighten to match the geometry of that inserted medium.
177  */
178 static void fd_empty_seek_hack(FDrive *drv)
179 {
180     drv->last_sect = 0xFF;
181     drv->max_track = 0xFF;
182 }
183 
184 static void fd_init(FDrive *drv)
185 {
186     /* Drive */
187     drv->perpendicular = 0;
188     /* Disk */
189     drv->disk = FLOPPY_DRIVE_TYPE_NONE;
190     drv->last_sect = 0;
191     drv->max_track = 0;
192     drv->ro = true;
193     drv->media_changed = 1;
194 }
195 
196 #define NUM_SIDES(drv) ((drv)->flags & FDISK_DBL_SIDES ? 2 : 1)
197 
198 static int fd_sector_calc(uint8_t head, uint8_t track, uint8_t sect,
199                           uint8_t last_sect, uint8_t num_sides)
200 {
201     return (((track * num_sides) + head) * last_sect) + sect - 1;
202 }
203 
204 /* Returns current position, in sectors, for given drive */
205 static int fd_sector(FDrive *drv)
206 {
207     return fd_sector_calc(drv->head, drv->track, drv->sect, drv->last_sect,
208                           NUM_SIDES(drv));
209 }
210 
211 /* Returns current position, in bytes, for given drive */
212 static int fd_offset(FDrive *drv)
213 {
214     g_assert(fd_sector(drv) < INT_MAX >> BDRV_SECTOR_BITS);
215     return fd_sector(drv) << BDRV_SECTOR_BITS;
216 }
217 
218 /* Seek to a new position:
219  * returns 0 if already on right track
220  * returns 1 if track changed
221  * returns 2 if track is invalid
222  * returns 3 if sector is invalid
223  * returns 4 if seek is disabled
224  */
225 static int fd_seek(FDrive *drv, uint8_t head, uint8_t track, uint8_t sect,
226                    int enable_seek)
227 {
228     uint32_t sector;
229     int ret;
230 
231     if (track > drv->max_track ||
232         (head != 0 && (drv->flags & FDISK_DBL_SIDES) == 0)) {
233         FLOPPY_DPRINTF("try to read %d %02x %02x (max=%d %d %02x %02x)\n",
234                        head, track, sect, 1,
235                        (drv->flags & FDISK_DBL_SIDES) == 0 ? 0 : 1,
236                        drv->max_track, drv->last_sect);
237         return 2;
238     }
239     if (sect > drv->last_sect) {
240         FLOPPY_DPRINTF("try to read %d %02x %02x (max=%d %d %02x %02x)\n",
241                        head, track, sect, 1,
242                        (drv->flags & FDISK_DBL_SIDES) == 0 ? 0 : 1,
243                        drv->max_track, drv->last_sect);
244         return 3;
245     }
246     sector = fd_sector_calc(head, track, sect, drv->last_sect, NUM_SIDES(drv));
247     ret = 0;
248     if (sector != fd_sector(drv)) {
249 #if 0
250         if (!enable_seek) {
251             FLOPPY_DPRINTF("error: no implicit seek %d %02x %02x"
252                            " (max=%d %02x %02x)\n",
253                            head, track, sect, 1, drv->max_track,
254                            drv->last_sect);
255             return 4;
256         }
257 #endif
258         drv->head = head;
259         if (drv->track != track) {
260             if (drv->blk != NULL && blk_is_inserted(drv->blk)) {
261                 drv->media_changed = 0;
262             }
263             ret = 1;
264         }
265         drv->track = track;
266         drv->sect = sect;
267     }
268 
269     if (drv->blk == NULL || !blk_is_inserted(drv->blk)) {
270         ret = 2;
271     }
272 
273     return ret;
274 }
275 
276 /* Set drive back to track 0 */
277 static void fd_recalibrate(FDrive *drv)
278 {
279     FLOPPY_DPRINTF("recalibrate\n");
280     fd_seek(drv, 0, 0, 1, 1);
281 }
282 
283 /**
284  * Determine geometry based on inserted diskette.
285  * Will not operate on an empty drive.
286  *
287  * @return: 0 on success, -1 if the drive is empty.
288  */
289 static int pick_geometry(FDrive *drv)
290 {
291     BlockBackend *blk = drv->blk;
292     const FDFormat *parse;
293     uint64_t nb_sectors, size;
294     int i;
295     int match, size_match, type_match;
296     bool magic = drv->drive == FLOPPY_DRIVE_TYPE_AUTO;
297 
298     /* We can only pick a geometry if we have a diskette. */
299     if (!drv->blk || !blk_is_inserted(drv->blk) ||
300         drv->drive == FLOPPY_DRIVE_TYPE_NONE)
301     {
302         return -1;
303     }
304 
305     /* We need to determine the likely geometry of the inserted medium.
306      * In order of preference, we look for:
307      * (1) The same drive type and number of sectors,
308      * (2) The same diskette size and number of sectors,
309      * (3) The same drive type.
310      *
311      * In all cases, matches that occur higher in the drive table will take
312      * precedence over matches that occur later in the table.
313      */
314     blk_get_geometry(blk, &nb_sectors);
315     match = size_match = type_match = -1;
316     for (i = 0; ; i++) {
317         parse = &fd_formats[i];
318         if (parse->drive == FLOPPY_DRIVE_TYPE_NONE) {
319             break;
320         }
321         size = (parse->max_head + 1) * parse->max_track * parse->last_sect;
322         if (nb_sectors == size) {
323             if (magic || parse->drive == drv->drive) {
324                 /* (1) perfect match -- nb_sectors and drive type */
325                 goto out;
326             } else if (drive_size(parse->drive) == drive_size(drv->drive)) {
327                 /* (2) size match -- nb_sectors and physical medium size */
328                 match = (match == -1) ? i : match;
329             } else {
330                 /* This is suspicious -- Did the user misconfigure? */
331                 size_match = (size_match == -1) ? i : size_match;
332             }
333         } else if (type_match == -1) {
334             if ((parse->drive == drv->drive) ||
335                 (magic && (parse->drive == get_fallback_drive_type(drv)))) {
336                 /* (3) type match -- nb_sectors mismatch, but matches the type
337                  *     specified explicitly by the user, or matches the fallback
338                  *     default type when using the drive autodetect mechanism */
339                 type_match = i;
340             }
341         }
342     }
343 
344     /* No exact match found */
345     if (match == -1) {
346         if (size_match != -1) {
347             parse = &fd_formats[size_match];
348             FLOPPY_DPRINTF("User requested floppy drive type '%s', "
349                            "but inserted medium appears to be a "
350                            "%"PRId64" sector '%s' type\n",
351                            FloppyDriveType_str(drv->drive),
352                            nb_sectors,
353                            FloppyDriveType_str(parse->drive));
354         }
355         assert(type_match != -1 && "misconfigured fd_format");
356         match = type_match;
357     }
358     parse = &(fd_formats[match]);
359 
360  out:
361     if (parse->max_head == 0) {
362         drv->flags &= ~FDISK_DBL_SIDES;
363     } else {
364         drv->flags |= FDISK_DBL_SIDES;
365     }
366     drv->max_track = parse->max_track;
367     drv->last_sect = parse->last_sect;
368     drv->disk = parse->drive;
369     drv->media_rate = parse->rate;
370     return 0;
371 }
372 
373 static void pick_drive_type(FDrive *drv)
374 {
375     if (drv->drive != FLOPPY_DRIVE_TYPE_AUTO) {
376         return;
377     }
378 
379     if (pick_geometry(drv) == 0) {
380         drv->drive = drv->disk;
381     } else {
382         drv->drive = get_fallback_drive_type(drv);
383     }
384 
385     g_assert(drv->drive != FLOPPY_DRIVE_TYPE_AUTO);
386 }
387 
388 /* Revalidate a disk drive after a disk change */
389 static void fd_revalidate(FDrive *drv)
390 {
391     int rc;
392 
393     FLOPPY_DPRINTF("revalidate\n");
394     if (drv->blk != NULL) {
395         drv->ro = !blk_is_writable(drv->blk);
396         if (!blk_is_inserted(drv->blk)) {
397             FLOPPY_DPRINTF("No disk in drive\n");
398             drv->disk = FLOPPY_DRIVE_TYPE_NONE;
399             fd_empty_seek_hack(drv);
400         } else if (!drv->media_validated) {
401             rc = pick_geometry(drv);
402             if (rc) {
403                 FLOPPY_DPRINTF("Could not validate floppy drive media");
404             } else {
405                 drv->media_validated = true;
406                 FLOPPY_DPRINTF("Floppy disk (%d h %d t %d s) %s\n",
407                                (drv->flags & FDISK_DBL_SIDES) ? 2 : 1,
408                                drv->max_track, drv->last_sect,
409                                drv->ro ? "ro" : "rw");
410             }
411         }
412     } else {
413         FLOPPY_DPRINTF("No drive connected\n");
414         drv->last_sect = 0;
415         drv->max_track = 0;
416         drv->flags &= ~FDISK_DBL_SIDES;
417         drv->drive = FLOPPY_DRIVE_TYPE_NONE;
418         drv->disk = FLOPPY_DRIVE_TYPE_NONE;
419     }
420 }
421 
422 static void fd_change_cb(void *opaque, bool load, Error **errp)
423 {
424     FDrive *drive = opaque;
425 
426     if (!load) {
427         blk_set_perm(drive->blk, 0, BLK_PERM_ALL, &error_abort);
428     } else {
429         if (!blkconf_apply_backend_options(drive->conf,
430                                            !blk_supports_write_perm(drive->blk),
431                                            false, errp)) {
432             return;
433         }
434     }
435 
436     drive->media_changed = 1;
437     drive->media_validated = false;
438     fd_revalidate(drive);
439 }
440 
441 static const BlockDevOps fd_block_ops = {
442     .change_media_cb = fd_change_cb,
443 };
444 
445 
446 #define TYPE_FLOPPY_DRIVE "floppy"
447 OBJECT_DECLARE_SIMPLE_TYPE(FloppyDrive, FLOPPY_DRIVE)
448 
449 struct FloppyDrive {
450     DeviceState     qdev;
451     uint32_t        unit;
452     BlockConf       conf;
453     FloppyDriveType type;
454 };
455 
456 static Property floppy_drive_properties[] = {
457     DEFINE_PROP_UINT32("unit", FloppyDrive, unit, -1),
458     DEFINE_BLOCK_PROPERTIES(FloppyDrive, conf),
459     DEFINE_PROP_SIGNED("drive-type", FloppyDrive, type,
460                         FLOPPY_DRIVE_TYPE_AUTO, qdev_prop_fdc_drive_type,
461                         FloppyDriveType),
462     DEFINE_PROP_END_OF_LIST(),
463 };
464 
465 static void floppy_drive_realize(DeviceState *qdev, Error **errp)
466 {
467     FloppyDrive *dev = FLOPPY_DRIVE(qdev);
468     FloppyBus *bus = FLOPPY_BUS(qdev->parent_bus);
469     FDrive *drive;
470     bool read_only;
471     int ret;
472 
473     if (dev->unit == -1) {
474         for (dev->unit = 0; dev->unit < MAX_FD; dev->unit++) {
475             drive = get_drv(bus->fdc, dev->unit);
476             if (!drive->blk) {
477                 break;
478             }
479         }
480     }
481 
482     if (dev->unit >= MAX_FD) {
483         error_setg(errp, "Can't create floppy unit %d, bus supports "
484                    "only %d units", dev->unit, MAX_FD);
485         return;
486     }
487 
488     drive = get_drv(bus->fdc, dev->unit);
489     if (drive->blk) {
490         error_setg(errp, "Floppy unit %d is in use", dev->unit);
491         return;
492     }
493 
494     if (!dev->conf.blk) {
495         dev->conf.blk = blk_create_empty_drive();
496         ret = blk_attach_dev(dev->conf.blk, qdev);
497         assert(ret == 0);
498 
499         /* Don't take write permissions on an empty drive to allow attaching a
500          * read-only node later */
501         read_only = true;
502     } else {
503         read_only = !blk_bs(dev->conf.blk) ||
504                     !blk_supports_write_perm(dev->conf.blk);
505     }
506 
507     if (!blkconf_blocksizes(&dev->conf, errp)) {
508         return;
509     }
510 
511     if (dev->conf.logical_block_size != 512 ||
512         dev->conf.physical_block_size != 512)
513     {
514         error_setg(errp, "Physical and logical block size must "
515                    "be 512 for floppy");
516         return;
517     }
518 
519     /* rerror/werror aren't supported by fdc and therefore not even registered
520      * with qdev. So set the defaults manually before they are used in
521      * blkconf_apply_backend_options(). */
522     dev->conf.rerror = BLOCKDEV_ON_ERROR_AUTO;
523     dev->conf.werror = BLOCKDEV_ON_ERROR_AUTO;
524 
525     if (!blkconf_apply_backend_options(&dev->conf, read_only, false, errp)) {
526         return;
527     }
528 
529     /* 'enospc' is the default for -drive, 'report' is what blk_new() gives us
530      * for empty drives. */
531     if (blk_get_on_error(dev->conf.blk, 0) != BLOCKDEV_ON_ERROR_ENOSPC &&
532         blk_get_on_error(dev->conf.blk, 0) != BLOCKDEV_ON_ERROR_REPORT) {
533         error_setg(errp, "fdc doesn't support drive option werror");
534         return;
535     }
536     if (blk_get_on_error(dev->conf.blk, 1) != BLOCKDEV_ON_ERROR_REPORT) {
537         error_setg(errp, "fdc doesn't support drive option rerror");
538         return;
539     }
540 
541     drive->conf = &dev->conf;
542     drive->blk = dev->conf.blk;
543     drive->fdctrl = bus->fdc;
544 
545     fd_init(drive);
546     blk_set_dev_ops(drive->blk, &fd_block_ops, drive);
547 
548     /* Keep 'type' qdev property and FDrive->drive in sync */
549     drive->drive = dev->type;
550     pick_drive_type(drive);
551     dev->type = drive->drive;
552 
553     fd_revalidate(drive);
554 }
555 
556 static void floppy_drive_class_init(ObjectClass *klass, void *data)
557 {
558     DeviceClass *k = DEVICE_CLASS(klass);
559     k->realize = floppy_drive_realize;
560     set_bit(DEVICE_CATEGORY_STORAGE, k->categories);
561     k->bus_type = TYPE_FLOPPY_BUS;
562     device_class_set_props(k, floppy_drive_properties);
563     k->desc = "virtual floppy drive";
564 }
565 
566 static const TypeInfo floppy_drive_info = {
567     .name = TYPE_FLOPPY_DRIVE,
568     .parent = TYPE_DEVICE,
569     .instance_size = sizeof(FloppyDrive),
570     .class_init = floppy_drive_class_init,
571 };
572 
573 /********************************************************/
574 /* Intel 82078 floppy disk controller emulation          */
575 
576 static void fdctrl_to_command_phase(FDCtrl *fdctrl);
577 static void fdctrl_raise_irq(FDCtrl *fdctrl);
578 static FDrive *get_cur_drv(FDCtrl *fdctrl);
579 
580 static uint32_t fdctrl_read_statusA(FDCtrl *fdctrl);
581 static uint32_t fdctrl_read_statusB(FDCtrl *fdctrl);
582 static uint32_t fdctrl_read_dor(FDCtrl *fdctrl);
583 static void fdctrl_write_dor(FDCtrl *fdctrl, uint32_t value);
584 static uint32_t fdctrl_read_tape(FDCtrl *fdctrl);
585 static void fdctrl_write_tape(FDCtrl *fdctrl, uint32_t value);
586 static uint32_t fdctrl_read_main_status(FDCtrl *fdctrl);
587 static void fdctrl_write_rate(FDCtrl *fdctrl, uint32_t value);
588 static uint32_t fdctrl_read_data(FDCtrl *fdctrl);
589 static void fdctrl_write_data(FDCtrl *fdctrl, uint32_t value);
590 static uint32_t fdctrl_read_dir(FDCtrl *fdctrl);
591 static void fdctrl_write_ccr(FDCtrl *fdctrl, uint32_t value);
592 
593 enum {
594     FD_DIR_WRITE   = 0,
595     FD_DIR_READ    = 1,
596     FD_DIR_SCANE   = 2,
597     FD_DIR_SCANL   = 3,
598     FD_DIR_SCANH   = 4,
599     FD_DIR_VERIFY  = 5,
600 };
601 
602 enum {
603     FD_STATE_MULTI  = 0x01,	/* multi track flag */
604     FD_STATE_FORMAT = 0x02,	/* format flag */
605 };
606 
607 enum {
608     FD_REG_SRA = 0x00,
609     FD_REG_SRB = 0x01,
610     FD_REG_DOR = 0x02,
611     FD_REG_TDR = 0x03,
612     FD_REG_MSR = 0x04,
613     FD_REG_DSR = 0x04,
614     FD_REG_FIFO = 0x05,
615     FD_REG_DIR = 0x07,
616     FD_REG_CCR = 0x07,
617 };
618 
619 enum {
620     FD_CMD_READ_TRACK = 0x02,
621     FD_CMD_SPECIFY = 0x03,
622     FD_CMD_SENSE_DRIVE_STATUS = 0x04,
623     FD_CMD_WRITE = 0x05,
624     FD_CMD_READ = 0x06,
625     FD_CMD_RECALIBRATE = 0x07,
626     FD_CMD_SENSE_INTERRUPT_STATUS = 0x08,
627     FD_CMD_WRITE_DELETED = 0x09,
628     FD_CMD_READ_ID = 0x0a,
629     FD_CMD_READ_DELETED = 0x0c,
630     FD_CMD_FORMAT_TRACK = 0x0d,
631     FD_CMD_DUMPREG = 0x0e,
632     FD_CMD_SEEK = 0x0f,
633     FD_CMD_VERSION = 0x10,
634     FD_CMD_SCAN_EQUAL = 0x11,
635     FD_CMD_PERPENDICULAR_MODE = 0x12,
636     FD_CMD_CONFIGURE = 0x13,
637     FD_CMD_LOCK = 0x14,
638     FD_CMD_VERIFY = 0x16,
639     FD_CMD_POWERDOWN_MODE = 0x17,
640     FD_CMD_PART_ID = 0x18,
641     FD_CMD_SCAN_LOW_OR_EQUAL = 0x19,
642     FD_CMD_SCAN_HIGH_OR_EQUAL = 0x1d,
643     FD_CMD_SAVE = 0x2e,
644     FD_CMD_OPTION = 0x33,
645     FD_CMD_RESTORE = 0x4e,
646     FD_CMD_DRIVE_SPECIFICATION_COMMAND = 0x8e,
647     FD_CMD_RELATIVE_SEEK_OUT = 0x8f,
648     FD_CMD_FORMAT_AND_WRITE = 0xcd,
649     FD_CMD_RELATIVE_SEEK_IN = 0xcf,
650 };
651 
652 enum {
653     FD_CONFIG_PRETRK = 0xff, /* Pre-compensation set to track 0 */
654     FD_CONFIG_FIFOTHR = 0x0f, /* FIFO threshold set to 1 byte */
655     FD_CONFIG_POLL  = 0x10, /* Poll enabled */
656     FD_CONFIG_EFIFO = 0x20, /* FIFO disabled */
657     FD_CONFIG_EIS   = 0x40, /* No implied seeks */
658 };
659 
660 enum {
661     FD_SR0_DS0      = 0x01,
662     FD_SR0_DS1      = 0x02,
663     FD_SR0_HEAD     = 0x04,
664     FD_SR0_EQPMT    = 0x10,
665     FD_SR0_SEEK     = 0x20,
666     FD_SR0_ABNTERM  = 0x40,
667     FD_SR0_INVCMD   = 0x80,
668     FD_SR0_RDYCHG   = 0xc0,
669 };
670 
671 enum {
672     FD_SR1_MA       = 0x01, /* Missing address mark */
673     FD_SR1_NW       = 0x02, /* Not writable */
674     FD_SR1_EC       = 0x80, /* End of cylinder */
675 };
676 
677 enum {
678     FD_SR2_SNS      = 0x04, /* Scan not satisfied */
679     FD_SR2_SEH      = 0x08, /* Scan equal hit */
680 };
681 
682 enum {
683     FD_SRA_DIR      = 0x01,
684     FD_SRA_nWP      = 0x02,
685     FD_SRA_nINDX    = 0x04,
686     FD_SRA_HDSEL    = 0x08,
687     FD_SRA_nTRK0    = 0x10,
688     FD_SRA_STEP     = 0x20,
689     FD_SRA_nDRV2    = 0x40,
690     FD_SRA_INTPEND  = 0x80,
691 };
692 
693 enum {
694     FD_SRB_MTR0     = 0x01,
695     FD_SRB_MTR1     = 0x02,
696     FD_SRB_WGATE    = 0x04,
697     FD_SRB_RDATA    = 0x08,
698     FD_SRB_WDATA    = 0x10,
699     FD_SRB_DR0      = 0x20,
700 };
701 
702 enum {
703 #if MAX_FD == 4
704     FD_DOR_SELMASK  = 0x03,
705 #else
706     FD_DOR_SELMASK  = 0x01,
707 #endif
708     FD_DOR_nRESET   = 0x04,
709     FD_DOR_DMAEN    = 0x08,
710     FD_DOR_MOTEN0   = 0x10,
711     FD_DOR_MOTEN1   = 0x20,
712     FD_DOR_MOTEN2   = 0x40,
713     FD_DOR_MOTEN3   = 0x80,
714 };
715 
716 enum {
717 #if MAX_FD == 4
718     FD_TDR_BOOTSEL  = 0x0c,
719 #else
720     FD_TDR_BOOTSEL  = 0x04,
721 #endif
722 };
723 
724 enum {
725     FD_DSR_DRATEMASK= 0x03,
726     FD_DSR_PWRDOWN  = 0x40,
727     FD_DSR_SWRESET  = 0x80,
728 };
729 
730 enum {
731     FD_MSR_DRV0BUSY = 0x01,
732     FD_MSR_DRV1BUSY = 0x02,
733     FD_MSR_DRV2BUSY = 0x04,
734     FD_MSR_DRV3BUSY = 0x08,
735     FD_MSR_CMDBUSY  = 0x10,
736     FD_MSR_NONDMA   = 0x20,
737     FD_MSR_DIO      = 0x40,
738     FD_MSR_RQM      = 0x80,
739 };
740 
741 enum {
742     FD_DIR_DSKCHG   = 0x80,
743 };
744 
745 /*
746  * See chapter 5.0 "Controller phases" of the spec:
747  *
748  * Command phase:
749  * The host writes a command and its parameters into the FIFO. The command
750  * phase is completed when all parameters for the command have been supplied,
751  * and execution phase is entered.
752  *
753  * Execution phase:
754  * Data transfers, either DMA or non-DMA. For non-DMA transfers, the FIFO
755  * contains the payload now, otherwise it's unused. When all bytes of the
756  * required data have been transferred, the state is switched to either result
757  * phase (if the command produces status bytes) or directly back into the
758  * command phase for the next command.
759  *
760  * Result phase:
761  * The host reads out the FIFO, which contains one or more result bytes now.
762  */
763 enum {
764     /* Only for migration: reconstruct phase from registers like qemu 2.3 */
765     FD_PHASE_RECONSTRUCT    = 0,
766 
767     FD_PHASE_COMMAND        = 1,
768     FD_PHASE_EXECUTION      = 2,
769     FD_PHASE_RESULT         = 3,
770 };
771 
772 #define FD_MULTI_TRACK(state) ((state) & FD_STATE_MULTI)
773 #define FD_FORMAT_CMD(state) ((state) & FD_STATE_FORMAT)
774 
775 static FloppyDriveType get_fallback_drive_type(FDrive *drv)
776 {
777     return drv->fdctrl->fallback;
778 }
779 
780 uint32_t fdctrl_read(void *opaque, uint32_t reg)
781 {
782     FDCtrl *fdctrl = opaque;
783     uint32_t retval;
784 
785     reg &= 7;
786     switch (reg) {
787     case FD_REG_SRA:
788         retval = fdctrl_read_statusA(fdctrl);
789         break;
790     case FD_REG_SRB:
791         retval = fdctrl_read_statusB(fdctrl);
792         break;
793     case FD_REG_DOR:
794         retval = fdctrl_read_dor(fdctrl);
795         break;
796     case FD_REG_TDR:
797         retval = fdctrl_read_tape(fdctrl);
798         break;
799     case FD_REG_MSR:
800         retval = fdctrl_read_main_status(fdctrl);
801         break;
802     case FD_REG_FIFO:
803         retval = fdctrl_read_data(fdctrl);
804         break;
805     case FD_REG_DIR:
806         retval = fdctrl_read_dir(fdctrl);
807         break;
808     default:
809         retval = (uint32_t)(-1);
810         break;
811     }
812     trace_fdc_ioport_read(reg, retval);
813 
814     return retval;
815 }
816 
817 void fdctrl_write(void *opaque, uint32_t reg, uint32_t value)
818 {
819     FDCtrl *fdctrl = opaque;
820 
821     reg &= 7;
822     trace_fdc_ioport_write(reg, value);
823     switch (reg) {
824     case FD_REG_DOR:
825         fdctrl_write_dor(fdctrl, value);
826         break;
827     case FD_REG_TDR:
828         fdctrl_write_tape(fdctrl, value);
829         break;
830     case FD_REG_DSR:
831         fdctrl_write_rate(fdctrl, value);
832         break;
833     case FD_REG_FIFO:
834         fdctrl_write_data(fdctrl, value);
835         break;
836     case FD_REG_CCR:
837         fdctrl_write_ccr(fdctrl, value);
838         break;
839     default:
840         break;
841     }
842 }
843 
844 static bool fdrive_media_changed_needed(void *opaque)
845 {
846     FDrive *drive = opaque;
847 
848     return (drive->blk != NULL && drive->media_changed != 1);
849 }
850 
851 static const VMStateDescription vmstate_fdrive_media_changed = {
852     .name = "fdrive/media_changed",
853     .version_id = 1,
854     .minimum_version_id = 1,
855     .needed = fdrive_media_changed_needed,
856     .fields = (VMStateField[]) {
857         VMSTATE_UINT8(media_changed, FDrive),
858         VMSTATE_END_OF_LIST()
859     }
860 };
861 
862 static const VMStateDescription vmstate_fdrive_media_rate = {
863     .name = "fdrive/media_rate",
864     .version_id = 1,
865     .minimum_version_id = 1,
866     .fields = (VMStateField[]) {
867         VMSTATE_UINT8(media_rate, FDrive),
868         VMSTATE_END_OF_LIST()
869     }
870 };
871 
872 static bool fdrive_perpendicular_needed(void *opaque)
873 {
874     FDrive *drive = opaque;
875 
876     return drive->perpendicular != 0;
877 }
878 
879 static const VMStateDescription vmstate_fdrive_perpendicular = {
880     .name = "fdrive/perpendicular",
881     .version_id = 1,
882     .minimum_version_id = 1,
883     .needed = fdrive_perpendicular_needed,
884     .fields = (VMStateField[]) {
885         VMSTATE_UINT8(perpendicular, FDrive),
886         VMSTATE_END_OF_LIST()
887     }
888 };
889 
890 static int fdrive_post_load(void *opaque, int version_id)
891 {
892     fd_revalidate(opaque);
893     return 0;
894 }
895 
896 static const VMStateDescription vmstate_fdrive = {
897     .name = "fdrive",
898     .version_id = 1,
899     .minimum_version_id = 1,
900     .post_load = fdrive_post_load,
901     .fields = (VMStateField[]) {
902         VMSTATE_UINT8(head, FDrive),
903         VMSTATE_UINT8(track, FDrive),
904         VMSTATE_UINT8(sect, FDrive),
905         VMSTATE_END_OF_LIST()
906     },
907     .subsections = (const VMStateDescription*[]) {
908         &vmstate_fdrive_media_changed,
909         &vmstate_fdrive_media_rate,
910         &vmstate_fdrive_perpendicular,
911         NULL
912     }
913 };
914 
915 /*
916  * Reconstructs the phase from register values according to the logic that was
917  * implemented in qemu 2.3. This is the default value that is used if the phase
918  * subsection is not present on migration.
919  *
920  * Don't change this function to reflect newer qemu versions, it is part of
921  * the migration ABI.
922  */
923 static int reconstruct_phase(FDCtrl *fdctrl)
924 {
925     if (fdctrl->msr & FD_MSR_NONDMA) {
926         return FD_PHASE_EXECUTION;
927     } else if ((fdctrl->msr & FD_MSR_RQM) == 0) {
928         /* qemu 2.3 disabled RQM only during DMA transfers */
929         return FD_PHASE_EXECUTION;
930     } else if (fdctrl->msr & FD_MSR_DIO) {
931         return FD_PHASE_RESULT;
932     } else {
933         return FD_PHASE_COMMAND;
934     }
935 }
936 
937 static int fdc_pre_save(void *opaque)
938 {
939     FDCtrl *s = opaque;
940 
941     s->dor_vmstate = s->dor | GET_CUR_DRV(s);
942 
943     return 0;
944 }
945 
946 static int fdc_pre_load(void *opaque)
947 {
948     FDCtrl *s = opaque;
949     s->phase = FD_PHASE_RECONSTRUCT;
950     return 0;
951 }
952 
953 static int fdc_post_load(void *opaque, int version_id)
954 {
955     FDCtrl *s = opaque;
956 
957     SET_CUR_DRV(s, s->dor_vmstate & FD_DOR_SELMASK);
958     s->dor = s->dor_vmstate & ~FD_DOR_SELMASK;
959 
960     if (s->phase == FD_PHASE_RECONSTRUCT) {
961         s->phase = reconstruct_phase(s);
962     }
963 
964     return 0;
965 }
966 
967 static bool fdc_reset_sensei_needed(void *opaque)
968 {
969     FDCtrl *s = opaque;
970 
971     return s->reset_sensei != 0;
972 }
973 
974 static const VMStateDescription vmstate_fdc_reset_sensei = {
975     .name = "fdc/reset_sensei",
976     .version_id = 1,
977     .minimum_version_id = 1,
978     .needed = fdc_reset_sensei_needed,
979     .fields = (VMStateField[]) {
980         VMSTATE_INT32(reset_sensei, FDCtrl),
981         VMSTATE_END_OF_LIST()
982     }
983 };
984 
985 static bool fdc_result_timer_needed(void *opaque)
986 {
987     FDCtrl *s = opaque;
988 
989     return timer_pending(s->result_timer);
990 }
991 
992 static const VMStateDescription vmstate_fdc_result_timer = {
993     .name = "fdc/result_timer",
994     .version_id = 1,
995     .minimum_version_id = 1,
996     .needed = fdc_result_timer_needed,
997     .fields = (VMStateField[]) {
998         VMSTATE_TIMER_PTR(result_timer, FDCtrl),
999         VMSTATE_END_OF_LIST()
1000     }
1001 };
1002 
1003 static bool fdc_phase_needed(void *opaque)
1004 {
1005     FDCtrl *fdctrl = opaque;
1006 
1007     return reconstruct_phase(fdctrl) != fdctrl->phase;
1008 }
1009 
1010 static const VMStateDescription vmstate_fdc_phase = {
1011     .name = "fdc/phase",
1012     .version_id = 1,
1013     .minimum_version_id = 1,
1014     .needed = fdc_phase_needed,
1015     .fields = (VMStateField[]) {
1016         VMSTATE_UINT8(phase, FDCtrl),
1017         VMSTATE_END_OF_LIST()
1018     }
1019 };
1020 
1021 const VMStateDescription vmstate_fdc = {
1022     .name = "fdc",
1023     .version_id = 2,
1024     .minimum_version_id = 2,
1025     .pre_save = fdc_pre_save,
1026     .pre_load = fdc_pre_load,
1027     .post_load = fdc_post_load,
1028     .fields = (VMStateField[]) {
1029         /* Controller State */
1030         VMSTATE_UINT8(sra, FDCtrl),
1031         VMSTATE_UINT8(srb, FDCtrl),
1032         VMSTATE_UINT8(dor_vmstate, FDCtrl),
1033         VMSTATE_UINT8(tdr, FDCtrl),
1034         VMSTATE_UINT8(dsr, FDCtrl),
1035         VMSTATE_UINT8(msr, FDCtrl),
1036         VMSTATE_UINT8(status0, FDCtrl),
1037         VMSTATE_UINT8(status1, FDCtrl),
1038         VMSTATE_UINT8(status2, FDCtrl),
1039         /* Command FIFO */
1040         VMSTATE_VARRAY_INT32(fifo, FDCtrl, fifo_size, 0, vmstate_info_uint8,
1041                              uint8_t),
1042         VMSTATE_UINT32(data_pos, FDCtrl),
1043         VMSTATE_UINT32(data_len, FDCtrl),
1044         VMSTATE_UINT8(data_state, FDCtrl),
1045         VMSTATE_UINT8(data_dir, FDCtrl),
1046         VMSTATE_UINT8(eot, FDCtrl),
1047         /* States kept only to be returned back */
1048         VMSTATE_UINT8(timer0, FDCtrl),
1049         VMSTATE_UINT8(timer1, FDCtrl),
1050         VMSTATE_UINT8(precomp_trk, FDCtrl),
1051         VMSTATE_UINT8(config, FDCtrl),
1052         VMSTATE_UINT8(lock, FDCtrl),
1053         VMSTATE_UINT8(pwrd, FDCtrl),
1054         VMSTATE_UINT8_EQUAL(num_floppies, FDCtrl, NULL),
1055         VMSTATE_STRUCT_ARRAY(drives, FDCtrl, MAX_FD, 1,
1056                              vmstate_fdrive, FDrive),
1057         VMSTATE_END_OF_LIST()
1058     },
1059     .subsections = (const VMStateDescription*[]) {
1060         &vmstate_fdc_reset_sensei,
1061         &vmstate_fdc_result_timer,
1062         &vmstate_fdc_phase,
1063         NULL
1064     }
1065 };
1066 
1067 /* Change IRQ state */
1068 static void fdctrl_reset_irq(FDCtrl *fdctrl)
1069 {
1070     fdctrl->status0 = 0;
1071     if (!(fdctrl->sra & FD_SRA_INTPEND))
1072         return;
1073     FLOPPY_DPRINTF("Reset interrupt\n");
1074     qemu_set_irq(fdctrl->irq, 0);
1075     fdctrl->sra &= ~FD_SRA_INTPEND;
1076 }
1077 
1078 static void fdctrl_raise_irq(FDCtrl *fdctrl)
1079 {
1080     if (!(fdctrl->sra & FD_SRA_INTPEND)) {
1081         qemu_set_irq(fdctrl->irq, 1);
1082         fdctrl->sra |= FD_SRA_INTPEND;
1083     }
1084 
1085     fdctrl->reset_sensei = 0;
1086     FLOPPY_DPRINTF("Set interrupt status to 0x%02x\n", fdctrl->status0);
1087 }
1088 
1089 /* Reset controller */
1090 void fdctrl_reset(FDCtrl *fdctrl, int do_irq)
1091 {
1092     int i;
1093 
1094     FLOPPY_DPRINTF("reset controller\n");
1095     fdctrl_reset_irq(fdctrl);
1096     /* Initialise controller */
1097     fdctrl->sra = 0;
1098     fdctrl->srb = 0xc0;
1099     if (!fdctrl->drives[1].blk) {
1100         fdctrl->sra |= FD_SRA_nDRV2;
1101     }
1102     fdctrl->cur_drv = 0;
1103     fdctrl->dor = FD_DOR_nRESET;
1104     fdctrl->dor |= (fdctrl->dma_chann != -1) ? FD_DOR_DMAEN : 0;
1105     fdctrl->msr = FD_MSR_RQM;
1106     fdctrl->reset_sensei = 0;
1107     timer_del(fdctrl->result_timer);
1108     /* FIFO state */
1109     fdctrl->data_pos = 0;
1110     fdctrl->data_len = 0;
1111     fdctrl->data_state = 0;
1112     fdctrl->data_dir = FD_DIR_WRITE;
1113     for (i = 0; i < MAX_FD; i++)
1114         fd_recalibrate(&fdctrl->drives[i]);
1115     fdctrl_to_command_phase(fdctrl);
1116     if (do_irq) {
1117         fdctrl->status0 |= FD_SR0_RDYCHG;
1118         fdctrl_raise_irq(fdctrl);
1119         fdctrl->reset_sensei = FD_RESET_SENSEI_COUNT;
1120     }
1121 }
1122 
1123 static inline FDrive *drv0(FDCtrl *fdctrl)
1124 {
1125     return &fdctrl->drives[(fdctrl->tdr & FD_TDR_BOOTSEL) >> 2];
1126 }
1127 
1128 static inline FDrive *drv1(FDCtrl *fdctrl)
1129 {
1130     if ((fdctrl->tdr & FD_TDR_BOOTSEL) < (1 << 2))
1131         return &fdctrl->drives[1];
1132     else
1133         return &fdctrl->drives[0];
1134 }
1135 
1136 #if MAX_FD == 4
1137 static inline FDrive *drv2(FDCtrl *fdctrl)
1138 {
1139     if ((fdctrl->tdr & FD_TDR_BOOTSEL) < (2 << 2))
1140         return &fdctrl->drives[2];
1141     else
1142         return &fdctrl->drives[1];
1143 }
1144 
1145 static inline FDrive *drv3(FDCtrl *fdctrl)
1146 {
1147     if ((fdctrl->tdr & FD_TDR_BOOTSEL) < (3 << 2))
1148         return &fdctrl->drives[3];
1149     else
1150         return &fdctrl->drives[2];
1151 }
1152 #endif
1153 
1154 static FDrive *get_drv(FDCtrl *fdctrl, int unit)
1155 {
1156     switch (unit) {
1157         case 0: return drv0(fdctrl);
1158         case 1: return drv1(fdctrl);
1159 #if MAX_FD == 4
1160         case 2: return drv2(fdctrl);
1161         case 3: return drv3(fdctrl);
1162 #endif
1163         default: return NULL;
1164     }
1165 }
1166 
1167 static FDrive *get_cur_drv(FDCtrl *fdctrl)
1168 {
1169     FDrive *cur_drv = get_drv(fdctrl, fdctrl->cur_drv);
1170 
1171     if (!cur_drv->blk) {
1172         /*
1173          * Kludge: empty drive line selected. Create an anonymous
1174          * BlockBackend to avoid NULL deref with various BlockBackend
1175          * API calls within this model (CVE-2021-20196).
1176          * Due to the controller QOM model limitations, we don't
1177          * attach the created to the controller device.
1178          */
1179         cur_drv->blk = blk_create_empty_drive();
1180     }
1181     return cur_drv;
1182 }
1183 
1184 /* Status A register : 0x00 (read-only) */
1185 static uint32_t fdctrl_read_statusA(FDCtrl *fdctrl)
1186 {
1187     uint32_t retval = fdctrl->sra;
1188 
1189     FLOPPY_DPRINTF("status register A: 0x%02x\n", retval);
1190 
1191     return retval;
1192 }
1193 
1194 /* Status B register : 0x01 (read-only) */
1195 static uint32_t fdctrl_read_statusB(FDCtrl *fdctrl)
1196 {
1197     uint32_t retval = fdctrl->srb;
1198 
1199     FLOPPY_DPRINTF("status register B: 0x%02x\n", retval);
1200 
1201     return retval;
1202 }
1203 
1204 /* Digital output register : 0x02 */
1205 static uint32_t fdctrl_read_dor(FDCtrl *fdctrl)
1206 {
1207     uint32_t retval = fdctrl->dor;
1208 
1209     /* Selected drive */
1210     retval |= fdctrl->cur_drv;
1211     FLOPPY_DPRINTF("digital output register: 0x%02x\n", retval);
1212 
1213     return retval;
1214 }
1215 
1216 static void fdctrl_write_dor(FDCtrl *fdctrl, uint32_t value)
1217 {
1218     FLOPPY_DPRINTF("digital output register set to 0x%02x\n", value);
1219 
1220     /* Motors */
1221     if (value & FD_DOR_MOTEN0)
1222         fdctrl->srb |= FD_SRB_MTR0;
1223     else
1224         fdctrl->srb &= ~FD_SRB_MTR0;
1225     if (value & FD_DOR_MOTEN1)
1226         fdctrl->srb |= FD_SRB_MTR1;
1227     else
1228         fdctrl->srb &= ~FD_SRB_MTR1;
1229 
1230     /* Drive */
1231     if (value & 1)
1232         fdctrl->srb |= FD_SRB_DR0;
1233     else
1234         fdctrl->srb &= ~FD_SRB_DR0;
1235 
1236     /* Reset */
1237     if (!(value & FD_DOR_nRESET)) {
1238         if (fdctrl->dor & FD_DOR_nRESET) {
1239             FLOPPY_DPRINTF("controller enter RESET state\n");
1240         }
1241     } else {
1242         if (!(fdctrl->dor & FD_DOR_nRESET)) {
1243             FLOPPY_DPRINTF("controller out of RESET state\n");
1244             fdctrl_reset(fdctrl, 1);
1245             fdctrl->dsr &= ~FD_DSR_PWRDOWN;
1246         }
1247     }
1248     /* Selected drive */
1249     fdctrl->cur_drv = value & FD_DOR_SELMASK;
1250 
1251     fdctrl->dor = value;
1252 }
1253 
1254 /* Tape drive register : 0x03 */
1255 static uint32_t fdctrl_read_tape(FDCtrl *fdctrl)
1256 {
1257     uint32_t retval = fdctrl->tdr;
1258 
1259     FLOPPY_DPRINTF("tape drive register: 0x%02x\n", retval);
1260 
1261     return retval;
1262 }
1263 
1264 static void fdctrl_write_tape(FDCtrl *fdctrl, uint32_t value)
1265 {
1266     /* Reset mode */
1267     if (!(fdctrl->dor & FD_DOR_nRESET)) {
1268         FLOPPY_DPRINTF("Floppy controller in RESET state !\n");
1269         return;
1270     }
1271     FLOPPY_DPRINTF("tape drive register set to 0x%02x\n", value);
1272     /* Disk boot selection indicator */
1273     fdctrl->tdr = value & FD_TDR_BOOTSEL;
1274     /* Tape indicators: never allow */
1275 }
1276 
1277 /* Main status register : 0x04 (read) */
1278 static uint32_t fdctrl_read_main_status(FDCtrl *fdctrl)
1279 {
1280     uint32_t retval = fdctrl->msr;
1281 
1282     fdctrl->dsr &= ~FD_DSR_PWRDOWN;
1283     fdctrl->dor |= FD_DOR_nRESET;
1284 
1285     FLOPPY_DPRINTF("main status register: 0x%02x\n", retval);
1286 
1287     return retval;
1288 }
1289 
1290 /* Data select rate register : 0x04 (write) */
1291 static void fdctrl_write_rate(FDCtrl *fdctrl, uint32_t value)
1292 {
1293     /* Reset mode */
1294     if (!(fdctrl->dor & FD_DOR_nRESET)) {
1295         FLOPPY_DPRINTF("Floppy controller in RESET state !\n");
1296         return;
1297     }
1298     FLOPPY_DPRINTF("select rate register set to 0x%02x\n", value);
1299     /* Reset: autoclear */
1300     if (value & FD_DSR_SWRESET) {
1301         fdctrl->dor &= ~FD_DOR_nRESET;
1302         fdctrl_reset(fdctrl, 1);
1303         fdctrl->dor |= FD_DOR_nRESET;
1304     }
1305     if (value & FD_DSR_PWRDOWN) {
1306         fdctrl_reset(fdctrl, 1);
1307     }
1308     fdctrl->dsr = value;
1309 }
1310 
1311 /* Configuration control register: 0x07 (write) */
1312 static void fdctrl_write_ccr(FDCtrl *fdctrl, uint32_t value)
1313 {
1314     /* Reset mode */
1315     if (!(fdctrl->dor & FD_DOR_nRESET)) {
1316         FLOPPY_DPRINTF("Floppy controller in RESET state !\n");
1317         return;
1318     }
1319     FLOPPY_DPRINTF("configuration control register set to 0x%02x\n", value);
1320 
1321     /* Only the rate selection bits used in AT mode, and we
1322      * store those in the DSR.
1323      */
1324     fdctrl->dsr = (fdctrl->dsr & ~FD_DSR_DRATEMASK) |
1325                   (value & FD_DSR_DRATEMASK);
1326 }
1327 
1328 static int fdctrl_media_changed(FDrive *drv)
1329 {
1330     return drv->media_changed;
1331 }
1332 
1333 /* Digital input register : 0x07 (read-only) */
1334 static uint32_t fdctrl_read_dir(FDCtrl *fdctrl)
1335 {
1336     uint32_t retval = 0;
1337 
1338     if (fdctrl_media_changed(get_cur_drv(fdctrl))) {
1339         retval |= FD_DIR_DSKCHG;
1340     }
1341     if (retval != 0) {
1342         FLOPPY_DPRINTF("Floppy digital input register: 0x%02x\n", retval);
1343     }
1344 
1345     return retval;
1346 }
1347 
1348 /* Clear the FIFO and update the state for receiving the next command */
1349 static void fdctrl_to_command_phase(FDCtrl *fdctrl)
1350 {
1351     fdctrl->phase = FD_PHASE_COMMAND;
1352     fdctrl->data_dir = FD_DIR_WRITE;
1353     fdctrl->data_pos = 0;
1354     fdctrl->data_len = 1; /* Accept command byte, adjust for params later */
1355     fdctrl->msr &= ~(FD_MSR_CMDBUSY | FD_MSR_DIO);
1356     fdctrl->msr |= FD_MSR_RQM;
1357 }
1358 
1359 /* Update the state to allow the guest to read out the command status.
1360  * @fifo_len is the number of result bytes to be read out. */
1361 static void fdctrl_to_result_phase(FDCtrl *fdctrl, int fifo_len)
1362 {
1363     fdctrl->phase = FD_PHASE_RESULT;
1364     fdctrl->data_dir = FD_DIR_READ;
1365     fdctrl->data_len = fifo_len;
1366     fdctrl->data_pos = 0;
1367     fdctrl->msr |= FD_MSR_CMDBUSY | FD_MSR_RQM | FD_MSR_DIO;
1368 }
1369 
1370 /* Set an error: unimplemented/unknown command */
1371 static void fdctrl_unimplemented(FDCtrl *fdctrl, int direction)
1372 {
1373     qemu_log_mask(LOG_UNIMP, "fdc: unimplemented command 0x%02x\n",
1374                   fdctrl->fifo[0]);
1375     fdctrl->fifo[0] = FD_SR0_INVCMD;
1376     fdctrl_to_result_phase(fdctrl, 1);
1377 }
1378 
1379 /* Seek to next sector
1380  * returns 0 when end of track reached (for DBL_SIDES on head 1)
1381  * otherwise returns 1
1382  */
1383 static int fdctrl_seek_to_next_sect(FDCtrl *fdctrl, FDrive *cur_drv)
1384 {
1385     FLOPPY_DPRINTF("seek to next sector (%d %02x %02x => %d)\n",
1386                    cur_drv->head, cur_drv->track, cur_drv->sect,
1387                    fd_sector(cur_drv));
1388     /* XXX: cur_drv->sect >= cur_drv->last_sect should be an
1389        error in fact */
1390     uint8_t new_head = cur_drv->head;
1391     uint8_t new_track = cur_drv->track;
1392     uint8_t new_sect = cur_drv->sect;
1393 
1394     int ret = 1;
1395 
1396     if (new_sect >= cur_drv->last_sect ||
1397         new_sect == fdctrl->eot) {
1398         new_sect = 1;
1399         if (FD_MULTI_TRACK(fdctrl->data_state)) {
1400             if (new_head == 0 &&
1401                 (cur_drv->flags & FDISK_DBL_SIDES) != 0) {
1402                 new_head = 1;
1403             } else {
1404                 new_head = 0;
1405                 new_track++;
1406                 fdctrl->status0 |= FD_SR0_SEEK;
1407                 if ((cur_drv->flags & FDISK_DBL_SIDES) == 0) {
1408                     ret = 0;
1409                 }
1410             }
1411         } else {
1412             fdctrl->status0 |= FD_SR0_SEEK;
1413             new_track++;
1414             ret = 0;
1415         }
1416         if (ret == 1) {
1417             FLOPPY_DPRINTF("seek to next track (%d %02x %02x => %d)\n",
1418                     new_head, new_track, new_sect, fd_sector(cur_drv));
1419         }
1420     } else {
1421         new_sect++;
1422     }
1423     fd_seek(cur_drv, new_head, new_track, new_sect, 1);
1424     return ret;
1425 }
1426 
1427 /* Callback for transfer end (stop or abort) */
1428 static void fdctrl_stop_transfer(FDCtrl *fdctrl, uint8_t status0,
1429                                  uint8_t status1, uint8_t status2)
1430 {
1431     FDrive *cur_drv;
1432     cur_drv = get_cur_drv(fdctrl);
1433 
1434     fdctrl->status0 &= ~(FD_SR0_DS0 | FD_SR0_DS1 | FD_SR0_HEAD);
1435     fdctrl->status0 |= GET_CUR_DRV(fdctrl);
1436     if (cur_drv->head) {
1437         fdctrl->status0 |= FD_SR0_HEAD;
1438     }
1439     fdctrl->status0 |= status0;
1440 
1441     FLOPPY_DPRINTF("transfer status: %02x %02x %02x (%02x)\n",
1442                    status0, status1, status2, fdctrl->status0);
1443     fdctrl->fifo[0] = fdctrl->status0;
1444     fdctrl->fifo[1] = status1;
1445     fdctrl->fifo[2] = status2;
1446     fdctrl->fifo[3] = cur_drv->track;
1447     fdctrl->fifo[4] = cur_drv->head;
1448     fdctrl->fifo[5] = cur_drv->sect;
1449     fdctrl->fifo[6] = FD_SECTOR_SC;
1450     fdctrl->data_dir = FD_DIR_READ;
1451     if (fdctrl->dma_chann != -1 && !(fdctrl->msr & FD_MSR_NONDMA)) {
1452         IsaDmaClass *k = ISADMA_GET_CLASS(fdctrl->dma);
1453         k->release_DREQ(fdctrl->dma, fdctrl->dma_chann);
1454     }
1455     fdctrl->msr |= FD_MSR_RQM | FD_MSR_DIO;
1456     fdctrl->msr &= ~FD_MSR_NONDMA;
1457 
1458     fdctrl_to_result_phase(fdctrl, 7);
1459     fdctrl_raise_irq(fdctrl);
1460 }
1461 
1462 /* Prepare a data transfer (either DMA or FIFO) */
1463 static void fdctrl_start_transfer(FDCtrl *fdctrl, int direction)
1464 {
1465     FDrive *cur_drv;
1466     uint8_t kh, kt, ks;
1467 
1468     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1469     cur_drv = get_cur_drv(fdctrl);
1470     kt = fdctrl->fifo[2];
1471     kh = fdctrl->fifo[3];
1472     ks = fdctrl->fifo[4];
1473     FLOPPY_DPRINTF("Start transfer at %d %d %02x %02x (%d)\n",
1474                    GET_CUR_DRV(fdctrl), kh, kt, ks,
1475                    fd_sector_calc(kh, kt, ks, cur_drv->last_sect,
1476                                   NUM_SIDES(cur_drv)));
1477     switch (fd_seek(cur_drv, kh, kt, ks, fdctrl->config & FD_CONFIG_EIS)) {
1478     case 2:
1479         /* sect too big */
1480         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1481         fdctrl->fifo[3] = kt;
1482         fdctrl->fifo[4] = kh;
1483         fdctrl->fifo[5] = ks;
1484         return;
1485     case 3:
1486         /* track too big */
1487         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_EC, 0x00);
1488         fdctrl->fifo[3] = kt;
1489         fdctrl->fifo[4] = kh;
1490         fdctrl->fifo[5] = ks;
1491         return;
1492     case 4:
1493         /* No seek enabled */
1494         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1495         fdctrl->fifo[3] = kt;
1496         fdctrl->fifo[4] = kh;
1497         fdctrl->fifo[5] = ks;
1498         return;
1499     case 1:
1500         fdctrl->status0 |= FD_SR0_SEEK;
1501         break;
1502     default:
1503         break;
1504     }
1505 
1506     /* Check the data rate. If the programmed data rate does not match
1507      * the currently inserted medium, the operation has to fail. */
1508     if ((fdctrl->dsr & FD_DSR_DRATEMASK) != cur_drv->media_rate) {
1509         FLOPPY_DPRINTF("data rate mismatch (fdc=%d, media=%d)\n",
1510                        fdctrl->dsr & FD_DSR_DRATEMASK, cur_drv->media_rate);
1511         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_MA, 0x00);
1512         fdctrl->fifo[3] = kt;
1513         fdctrl->fifo[4] = kh;
1514         fdctrl->fifo[5] = ks;
1515         return;
1516     }
1517 
1518     /* Set the FIFO state */
1519     fdctrl->data_dir = direction;
1520     fdctrl->data_pos = 0;
1521     assert(fdctrl->msr & FD_MSR_CMDBUSY);
1522     if (fdctrl->fifo[0] & 0x80)
1523         fdctrl->data_state |= FD_STATE_MULTI;
1524     else
1525         fdctrl->data_state &= ~FD_STATE_MULTI;
1526     if (fdctrl->fifo[5] == 0) {
1527         fdctrl->data_len = fdctrl->fifo[8];
1528     } else {
1529         int tmp;
1530         fdctrl->data_len = 128 << (fdctrl->fifo[5] > 7 ? 7 : fdctrl->fifo[5]);
1531         tmp = (fdctrl->fifo[6] - ks + 1);
1532         if (fdctrl->fifo[0] & 0x80)
1533             tmp += fdctrl->fifo[6];
1534         fdctrl->data_len *= tmp;
1535     }
1536     fdctrl->eot = fdctrl->fifo[6];
1537     if (fdctrl->dor & FD_DOR_DMAEN) {
1538         /* DMA transfer is enabled. */
1539         IsaDmaClass *k = ISADMA_GET_CLASS(fdctrl->dma);
1540 
1541         FLOPPY_DPRINTF("direction=%d (%d - %d)\n",
1542                        direction, (128 << fdctrl->fifo[5]) *
1543                        (cur_drv->last_sect - ks + 1), fdctrl->data_len);
1544 
1545         /* No access is allowed until DMA transfer has completed */
1546         fdctrl->msr &= ~FD_MSR_RQM;
1547         if (direction != FD_DIR_VERIFY) {
1548             /*
1549              * Now, we just have to wait for the DMA controller to
1550              * recall us...
1551              */
1552             k->hold_DREQ(fdctrl->dma, fdctrl->dma_chann);
1553             k->schedule(fdctrl->dma);
1554         } else {
1555             /* Start transfer */
1556             fdctrl_transfer_handler(fdctrl, fdctrl->dma_chann, 0,
1557                     fdctrl->data_len);
1558         }
1559         return;
1560     }
1561     FLOPPY_DPRINTF("start non-DMA transfer\n");
1562     fdctrl->msr |= FD_MSR_NONDMA | FD_MSR_RQM;
1563     if (direction != FD_DIR_WRITE)
1564         fdctrl->msr |= FD_MSR_DIO;
1565     /* IO based transfer: calculate len */
1566     fdctrl_raise_irq(fdctrl);
1567 }
1568 
1569 /* Prepare a transfer of deleted data */
1570 static void fdctrl_start_transfer_del(FDCtrl *fdctrl, int direction)
1571 {
1572     qemu_log_mask(LOG_UNIMP, "fdctrl_start_transfer_del() unimplemented\n");
1573 
1574     /* We don't handle deleted data,
1575      * so we don't return *ANYTHING*
1576      */
1577     fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
1578 }
1579 
1580 /* handlers for DMA transfers */
1581 int fdctrl_transfer_handler(void *opaque, int nchan, int dma_pos, int dma_len)
1582 {
1583     FDCtrl *fdctrl;
1584     FDrive *cur_drv;
1585     int len, start_pos, rel_pos;
1586     uint8_t status0 = 0x00, status1 = 0x00, status2 = 0x00;
1587     IsaDmaClass *k;
1588 
1589     fdctrl = opaque;
1590     if (fdctrl->msr & FD_MSR_RQM) {
1591         FLOPPY_DPRINTF("Not in DMA transfer mode !\n");
1592         return 0;
1593     }
1594     k = ISADMA_GET_CLASS(fdctrl->dma);
1595     cur_drv = get_cur_drv(fdctrl);
1596     if (fdctrl->data_dir == FD_DIR_SCANE || fdctrl->data_dir == FD_DIR_SCANL ||
1597         fdctrl->data_dir == FD_DIR_SCANH)
1598         status2 = FD_SR2_SNS;
1599     if (dma_len > fdctrl->data_len)
1600         dma_len = fdctrl->data_len;
1601     if (cur_drv->blk == NULL) {
1602         if (fdctrl->data_dir == FD_DIR_WRITE)
1603             fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
1604         else
1605             fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1606         len = 0;
1607         goto transfer_error;
1608     }
1609     rel_pos = fdctrl->data_pos % FD_SECTOR_LEN;
1610     for (start_pos = fdctrl->data_pos; fdctrl->data_pos < dma_len;) {
1611         len = dma_len - fdctrl->data_pos;
1612         if (len + rel_pos > FD_SECTOR_LEN)
1613             len = FD_SECTOR_LEN - rel_pos;
1614         FLOPPY_DPRINTF("copy %d bytes (%d %d %d) %d pos %d %02x "
1615                        "(%d-0x%08x 0x%08x)\n", len, dma_len, fdctrl->data_pos,
1616                        fdctrl->data_len, GET_CUR_DRV(fdctrl), cur_drv->head,
1617                        cur_drv->track, cur_drv->sect, fd_sector(cur_drv),
1618                        fd_sector(cur_drv) * FD_SECTOR_LEN);
1619         if (fdctrl->data_dir != FD_DIR_WRITE ||
1620             len < FD_SECTOR_LEN || rel_pos != 0) {
1621             /* READ & SCAN commands and realign to a sector for WRITE */
1622             if (blk_pread(cur_drv->blk, fd_offset(cur_drv),
1623                           fdctrl->fifo, BDRV_SECTOR_SIZE) < 0) {
1624                 FLOPPY_DPRINTF("Floppy: error getting sector %d\n",
1625                                fd_sector(cur_drv));
1626                 /* Sure, image size is too small... */
1627                 memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
1628             }
1629         }
1630         switch (fdctrl->data_dir) {
1631         case FD_DIR_READ:
1632             /* READ commands */
1633             k->write_memory(fdctrl->dma, nchan, fdctrl->fifo + rel_pos,
1634                             fdctrl->data_pos, len);
1635             break;
1636         case FD_DIR_WRITE:
1637             /* WRITE commands */
1638             if (cur_drv->ro) {
1639                 /* Handle readonly medium early, no need to do DMA, touch the
1640                  * LED or attempt any writes. A real floppy doesn't attempt
1641                  * to write to readonly media either. */
1642                 fdctrl_stop_transfer(fdctrl,
1643                                      FD_SR0_ABNTERM | FD_SR0_SEEK, FD_SR1_NW,
1644                                      0x00);
1645                 goto transfer_error;
1646             }
1647 
1648             k->read_memory(fdctrl->dma, nchan, fdctrl->fifo + rel_pos,
1649                            fdctrl->data_pos, len);
1650             if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv),
1651                            fdctrl->fifo, BDRV_SECTOR_SIZE, 0) < 0) {
1652                 FLOPPY_DPRINTF("error writing sector %d\n",
1653                                fd_sector(cur_drv));
1654                 fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
1655                 goto transfer_error;
1656             }
1657             break;
1658         case FD_DIR_VERIFY:
1659             /* VERIFY commands */
1660             break;
1661         default:
1662             /* SCAN commands */
1663             {
1664                 uint8_t tmpbuf[FD_SECTOR_LEN];
1665                 int ret;
1666                 k->read_memory(fdctrl->dma, nchan, tmpbuf, fdctrl->data_pos,
1667                                len);
1668                 ret = memcmp(tmpbuf, fdctrl->fifo + rel_pos, len);
1669                 if (ret == 0) {
1670                     status2 = FD_SR2_SEH;
1671                     goto end_transfer;
1672                 }
1673                 if ((ret < 0 && fdctrl->data_dir == FD_DIR_SCANL) ||
1674                     (ret > 0 && fdctrl->data_dir == FD_DIR_SCANH)) {
1675                     status2 = 0x00;
1676                     goto end_transfer;
1677                 }
1678             }
1679             break;
1680         }
1681         fdctrl->data_pos += len;
1682         rel_pos = fdctrl->data_pos % FD_SECTOR_LEN;
1683         if (rel_pos == 0) {
1684             /* Seek to next sector */
1685             if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv))
1686                 break;
1687         }
1688     }
1689  end_transfer:
1690     len = fdctrl->data_pos - start_pos;
1691     FLOPPY_DPRINTF("end transfer %d %d %d\n",
1692                    fdctrl->data_pos, len, fdctrl->data_len);
1693     if (fdctrl->data_dir == FD_DIR_SCANE ||
1694         fdctrl->data_dir == FD_DIR_SCANL ||
1695         fdctrl->data_dir == FD_DIR_SCANH)
1696         status2 = FD_SR2_SEH;
1697     fdctrl->data_len -= len;
1698     fdctrl_stop_transfer(fdctrl, status0, status1, status2);
1699  transfer_error:
1700 
1701     return len;
1702 }
1703 
1704 /* Data register : 0x05 */
1705 static uint32_t fdctrl_read_data(FDCtrl *fdctrl)
1706 {
1707     FDrive *cur_drv;
1708     uint32_t retval = 0;
1709     uint32_t pos;
1710 
1711     cur_drv = get_cur_drv(fdctrl);
1712     fdctrl->dsr &= ~FD_DSR_PWRDOWN;
1713     if (!(fdctrl->msr & FD_MSR_RQM) || !(fdctrl->msr & FD_MSR_DIO)) {
1714         FLOPPY_DPRINTF("error: controller not ready for reading\n");
1715         return 0;
1716     }
1717 
1718     /* If data_len spans multiple sectors, the current position in the FIFO
1719      * wraps around while fdctrl->data_pos is the real position in the whole
1720      * request. */
1721     pos = fdctrl->data_pos;
1722     pos %= FD_SECTOR_LEN;
1723 
1724     switch (fdctrl->phase) {
1725     case FD_PHASE_EXECUTION:
1726         assert(fdctrl->msr & FD_MSR_NONDMA);
1727         if (pos == 0) {
1728             if (fdctrl->data_pos != 0)
1729                 if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv)) {
1730                     FLOPPY_DPRINTF("error seeking to next sector %d\n",
1731                                    fd_sector(cur_drv));
1732                     return 0;
1733                 }
1734             if (blk_pread(cur_drv->blk, fd_offset(cur_drv), fdctrl->fifo,
1735                           BDRV_SECTOR_SIZE)
1736                 < 0) {
1737                 FLOPPY_DPRINTF("error getting sector %d\n",
1738                                fd_sector(cur_drv));
1739                 /* Sure, image size is too small... */
1740                 memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
1741             }
1742         }
1743 
1744         if (++fdctrl->data_pos == fdctrl->data_len) {
1745             fdctrl->msr &= ~FD_MSR_RQM;
1746             fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
1747         }
1748         break;
1749 
1750     case FD_PHASE_RESULT:
1751         assert(!(fdctrl->msr & FD_MSR_NONDMA));
1752         if (++fdctrl->data_pos == fdctrl->data_len) {
1753             fdctrl->msr &= ~FD_MSR_RQM;
1754             fdctrl_to_command_phase(fdctrl);
1755             fdctrl_reset_irq(fdctrl);
1756         }
1757         break;
1758 
1759     case FD_PHASE_COMMAND:
1760     default:
1761         abort();
1762     }
1763 
1764     retval = fdctrl->fifo[pos];
1765     FLOPPY_DPRINTF("data register: 0x%02x\n", retval);
1766 
1767     return retval;
1768 }
1769 
1770 static void fdctrl_format_sector(FDCtrl *fdctrl)
1771 {
1772     FDrive *cur_drv;
1773     uint8_t kh, kt, ks;
1774 
1775     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1776     cur_drv = get_cur_drv(fdctrl);
1777     kt = fdctrl->fifo[6];
1778     kh = fdctrl->fifo[7];
1779     ks = fdctrl->fifo[8];
1780     FLOPPY_DPRINTF("format sector at %d %d %02x %02x (%d)\n",
1781                    GET_CUR_DRV(fdctrl), kh, kt, ks,
1782                    fd_sector_calc(kh, kt, ks, cur_drv->last_sect,
1783                                   NUM_SIDES(cur_drv)));
1784     switch (fd_seek(cur_drv, kh, kt, ks, fdctrl->config & FD_CONFIG_EIS)) {
1785     case 2:
1786         /* sect too big */
1787         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1788         fdctrl->fifo[3] = kt;
1789         fdctrl->fifo[4] = kh;
1790         fdctrl->fifo[5] = ks;
1791         return;
1792     case 3:
1793         /* track too big */
1794         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_EC, 0x00);
1795         fdctrl->fifo[3] = kt;
1796         fdctrl->fifo[4] = kh;
1797         fdctrl->fifo[5] = ks;
1798         return;
1799     case 4:
1800         /* No seek enabled */
1801         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1802         fdctrl->fifo[3] = kt;
1803         fdctrl->fifo[4] = kh;
1804         fdctrl->fifo[5] = ks;
1805         return;
1806     case 1:
1807         fdctrl->status0 |= FD_SR0_SEEK;
1808         break;
1809     default:
1810         break;
1811     }
1812     memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
1813     if (cur_drv->blk == NULL ||
1814         blk_pwrite(cur_drv->blk, fd_offset(cur_drv), fdctrl->fifo,
1815                    BDRV_SECTOR_SIZE, 0) < 0) {
1816         FLOPPY_DPRINTF("error formatting sector %d\n", fd_sector(cur_drv));
1817         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
1818     } else {
1819         if (cur_drv->sect == cur_drv->last_sect) {
1820             fdctrl->data_state &= ~FD_STATE_FORMAT;
1821             /* Last sector done */
1822             fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
1823         } else {
1824             /* More to do */
1825             fdctrl->data_pos = 0;
1826             fdctrl->data_len = 4;
1827         }
1828     }
1829 }
1830 
1831 static void fdctrl_handle_lock(FDCtrl *fdctrl, int direction)
1832 {
1833     fdctrl->lock = (fdctrl->fifo[0] & 0x80) ? 1 : 0;
1834     fdctrl->fifo[0] = fdctrl->lock << 4;
1835     fdctrl_to_result_phase(fdctrl, 1);
1836 }
1837 
1838 static void fdctrl_handle_dumpreg(FDCtrl *fdctrl, int direction)
1839 {
1840     FDrive *cur_drv = get_cur_drv(fdctrl);
1841 
1842     /* Drives position */
1843     fdctrl->fifo[0] = drv0(fdctrl)->track;
1844     fdctrl->fifo[1] = drv1(fdctrl)->track;
1845 #if MAX_FD == 4
1846     fdctrl->fifo[2] = drv2(fdctrl)->track;
1847     fdctrl->fifo[3] = drv3(fdctrl)->track;
1848 #else
1849     fdctrl->fifo[2] = 0;
1850     fdctrl->fifo[3] = 0;
1851 #endif
1852     /* timers */
1853     fdctrl->fifo[4] = fdctrl->timer0;
1854     fdctrl->fifo[5] = (fdctrl->timer1 << 1) | (fdctrl->dor & FD_DOR_DMAEN ? 1 : 0);
1855     fdctrl->fifo[6] = cur_drv->last_sect;
1856     fdctrl->fifo[7] = (fdctrl->lock << 7) |
1857         (cur_drv->perpendicular << 2);
1858     fdctrl->fifo[8] = fdctrl->config;
1859     fdctrl->fifo[9] = fdctrl->precomp_trk;
1860     fdctrl_to_result_phase(fdctrl, 10);
1861 }
1862 
1863 static void fdctrl_handle_version(FDCtrl *fdctrl, int direction)
1864 {
1865     /* Controller's version */
1866     fdctrl->fifo[0] = fdctrl->version;
1867     fdctrl_to_result_phase(fdctrl, 1);
1868 }
1869 
1870 static void fdctrl_handle_partid(FDCtrl *fdctrl, int direction)
1871 {
1872     fdctrl->fifo[0] = 0x41; /* Stepping 1 */
1873     fdctrl_to_result_phase(fdctrl, 1);
1874 }
1875 
1876 static void fdctrl_handle_restore(FDCtrl *fdctrl, int direction)
1877 {
1878     FDrive *cur_drv = get_cur_drv(fdctrl);
1879 
1880     /* Drives position */
1881     drv0(fdctrl)->track = fdctrl->fifo[3];
1882     drv1(fdctrl)->track = fdctrl->fifo[4];
1883 #if MAX_FD == 4
1884     drv2(fdctrl)->track = fdctrl->fifo[5];
1885     drv3(fdctrl)->track = fdctrl->fifo[6];
1886 #endif
1887     /* timers */
1888     fdctrl->timer0 = fdctrl->fifo[7];
1889     fdctrl->timer1 = fdctrl->fifo[8];
1890     cur_drv->last_sect = fdctrl->fifo[9];
1891     fdctrl->lock = fdctrl->fifo[10] >> 7;
1892     cur_drv->perpendicular = (fdctrl->fifo[10] >> 2) & 0xF;
1893     fdctrl->config = fdctrl->fifo[11];
1894     fdctrl->precomp_trk = fdctrl->fifo[12];
1895     fdctrl->pwrd = fdctrl->fifo[13];
1896     fdctrl_to_command_phase(fdctrl);
1897 }
1898 
1899 static void fdctrl_handle_save(FDCtrl *fdctrl, int direction)
1900 {
1901     FDrive *cur_drv = get_cur_drv(fdctrl);
1902 
1903     fdctrl->fifo[0] = 0;
1904     fdctrl->fifo[1] = 0;
1905     /* Drives position */
1906     fdctrl->fifo[2] = drv0(fdctrl)->track;
1907     fdctrl->fifo[3] = drv1(fdctrl)->track;
1908 #if MAX_FD == 4
1909     fdctrl->fifo[4] = drv2(fdctrl)->track;
1910     fdctrl->fifo[5] = drv3(fdctrl)->track;
1911 #else
1912     fdctrl->fifo[4] = 0;
1913     fdctrl->fifo[5] = 0;
1914 #endif
1915     /* timers */
1916     fdctrl->fifo[6] = fdctrl->timer0;
1917     fdctrl->fifo[7] = fdctrl->timer1;
1918     fdctrl->fifo[8] = cur_drv->last_sect;
1919     fdctrl->fifo[9] = (fdctrl->lock << 7) |
1920         (cur_drv->perpendicular << 2);
1921     fdctrl->fifo[10] = fdctrl->config;
1922     fdctrl->fifo[11] = fdctrl->precomp_trk;
1923     fdctrl->fifo[12] = fdctrl->pwrd;
1924     fdctrl->fifo[13] = 0;
1925     fdctrl->fifo[14] = 0;
1926     fdctrl_to_result_phase(fdctrl, 15);
1927 }
1928 
1929 static void fdctrl_handle_readid(FDCtrl *fdctrl, int direction)
1930 {
1931     FDrive *cur_drv = get_cur_drv(fdctrl);
1932 
1933     cur_drv->head = (fdctrl->fifo[1] >> 2) & 1;
1934     timer_mod(fdctrl->result_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
1935              (NANOSECONDS_PER_SECOND / 50));
1936 }
1937 
1938 static void fdctrl_handle_format_track(FDCtrl *fdctrl, int direction)
1939 {
1940     FDrive *cur_drv;
1941 
1942     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1943     cur_drv = get_cur_drv(fdctrl);
1944     fdctrl->data_state |= FD_STATE_FORMAT;
1945     if (fdctrl->fifo[0] & 0x80)
1946         fdctrl->data_state |= FD_STATE_MULTI;
1947     else
1948         fdctrl->data_state &= ~FD_STATE_MULTI;
1949     cur_drv->bps =
1950         fdctrl->fifo[2] > 7 ? 16384 : 128 << fdctrl->fifo[2];
1951 #if 0
1952     cur_drv->last_sect =
1953         cur_drv->flags & FDISK_DBL_SIDES ? fdctrl->fifo[3] :
1954         fdctrl->fifo[3] / 2;
1955 #else
1956     cur_drv->last_sect = fdctrl->fifo[3];
1957 #endif
1958     /* TODO: implement format using DMA expected by the Bochs BIOS
1959      * and Linux fdformat (read 3 bytes per sector via DMA and fill
1960      * the sector with the specified fill byte
1961      */
1962     fdctrl->data_state &= ~FD_STATE_FORMAT;
1963     fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
1964 }
1965 
1966 static void fdctrl_handle_specify(FDCtrl *fdctrl, int direction)
1967 {
1968     fdctrl->timer0 = (fdctrl->fifo[1] >> 4) & 0xF;
1969     fdctrl->timer1 = fdctrl->fifo[2] >> 1;
1970     if (fdctrl->fifo[2] & 1)
1971         fdctrl->dor &= ~FD_DOR_DMAEN;
1972     else
1973         fdctrl->dor |= FD_DOR_DMAEN;
1974     /* No result back */
1975     fdctrl_to_command_phase(fdctrl);
1976 }
1977 
1978 static void fdctrl_handle_sense_drive_status(FDCtrl *fdctrl, int direction)
1979 {
1980     FDrive *cur_drv;
1981 
1982     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1983     cur_drv = get_cur_drv(fdctrl);
1984     cur_drv->head = (fdctrl->fifo[1] >> 2) & 1;
1985     /* 1 Byte status back */
1986     fdctrl->fifo[0] = (cur_drv->ro << 6) |
1987         (cur_drv->track == 0 ? 0x10 : 0x00) |
1988         (cur_drv->head << 2) |
1989         GET_CUR_DRV(fdctrl) |
1990         0x28;
1991     fdctrl_to_result_phase(fdctrl, 1);
1992 }
1993 
1994 static void fdctrl_handle_recalibrate(FDCtrl *fdctrl, int direction)
1995 {
1996     FDrive *cur_drv;
1997 
1998     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1999     cur_drv = get_cur_drv(fdctrl);
2000     fd_recalibrate(cur_drv);
2001     fdctrl_to_command_phase(fdctrl);
2002     /* Raise Interrupt */
2003     fdctrl->status0 |= FD_SR0_SEEK;
2004     fdctrl_raise_irq(fdctrl);
2005 }
2006 
2007 static void fdctrl_handle_sense_interrupt_status(FDCtrl *fdctrl, int direction)
2008 {
2009     FDrive *cur_drv = get_cur_drv(fdctrl);
2010 
2011     if (fdctrl->reset_sensei > 0) {
2012         fdctrl->fifo[0] =
2013             FD_SR0_RDYCHG + FD_RESET_SENSEI_COUNT - fdctrl->reset_sensei;
2014         fdctrl->reset_sensei--;
2015     } else if (!(fdctrl->sra & FD_SRA_INTPEND)) {
2016         fdctrl->fifo[0] = FD_SR0_INVCMD;
2017         fdctrl_to_result_phase(fdctrl, 1);
2018         return;
2019     } else {
2020         fdctrl->fifo[0] =
2021                 (fdctrl->status0 & ~(FD_SR0_HEAD | FD_SR0_DS1 | FD_SR0_DS0))
2022                 | GET_CUR_DRV(fdctrl);
2023     }
2024 
2025     fdctrl->fifo[1] = cur_drv->track;
2026     fdctrl_to_result_phase(fdctrl, 2);
2027     fdctrl_reset_irq(fdctrl);
2028     fdctrl->status0 = FD_SR0_RDYCHG;
2029 }
2030 
2031 static void fdctrl_handle_seek(FDCtrl *fdctrl, int direction)
2032 {
2033     FDrive *cur_drv;
2034 
2035     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
2036     cur_drv = get_cur_drv(fdctrl);
2037     fdctrl_to_command_phase(fdctrl);
2038     /* The seek command just sends step pulses to the drive and doesn't care if
2039      * there is a medium inserted of if it's banging the head against the drive.
2040      */
2041     fd_seek(cur_drv, cur_drv->head, fdctrl->fifo[2], cur_drv->sect, 1);
2042     /* Raise Interrupt */
2043     fdctrl->status0 |= FD_SR0_SEEK;
2044     fdctrl_raise_irq(fdctrl);
2045 }
2046 
2047 static void fdctrl_handle_perpendicular_mode(FDCtrl *fdctrl, int direction)
2048 {
2049     FDrive *cur_drv = get_cur_drv(fdctrl);
2050 
2051     if (fdctrl->fifo[1] & 0x80)
2052         cur_drv->perpendicular = fdctrl->fifo[1] & 0x7;
2053     /* No result back */
2054     fdctrl_to_command_phase(fdctrl);
2055 }
2056 
2057 static void fdctrl_handle_configure(FDCtrl *fdctrl, int direction)
2058 {
2059     fdctrl->config = fdctrl->fifo[2];
2060     fdctrl->precomp_trk =  fdctrl->fifo[3];
2061     /* No result back */
2062     fdctrl_to_command_phase(fdctrl);
2063 }
2064 
2065 static void fdctrl_handle_powerdown_mode(FDCtrl *fdctrl, int direction)
2066 {
2067     fdctrl->pwrd = fdctrl->fifo[1];
2068     fdctrl->fifo[0] = fdctrl->fifo[1];
2069     fdctrl_to_result_phase(fdctrl, 1);
2070 }
2071 
2072 static void fdctrl_handle_option(FDCtrl *fdctrl, int direction)
2073 {
2074     /* No result back */
2075     fdctrl_to_command_phase(fdctrl);
2076 }
2077 
2078 static void fdctrl_handle_drive_specification_command(FDCtrl *fdctrl, int direction)
2079 {
2080     FDrive *cur_drv = get_cur_drv(fdctrl);
2081     uint32_t pos;
2082 
2083     pos = fdctrl->data_pos - 1;
2084     pos %= FD_SECTOR_LEN;
2085     if (fdctrl->fifo[pos] & 0x80) {
2086         /* Command parameters done */
2087         if (fdctrl->fifo[pos] & 0x40) {
2088             fdctrl->fifo[0] = fdctrl->fifo[1];
2089             fdctrl->fifo[2] = 0;
2090             fdctrl->fifo[3] = 0;
2091             fdctrl_to_result_phase(fdctrl, 4);
2092         } else {
2093             fdctrl_to_command_phase(fdctrl);
2094         }
2095     } else if (fdctrl->data_len > 7) {
2096         /* ERROR */
2097         fdctrl->fifo[0] = 0x80 |
2098             (cur_drv->head << 2) | GET_CUR_DRV(fdctrl);
2099         fdctrl_to_result_phase(fdctrl, 1);
2100     }
2101 }
2102 
2103 static void fdctrl_handle_relative_seek_in(FDCtrl *fdctrl, int direction)
2104 {
2105     FDrive *cur_drv;
2106 
2107     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
2108     cur_drv = get_cur_drv(fdctrl);
2109     if (fdctrl->fifo[2] + cur_drv->track >= cur_drv->max_track) {
2110         fd_seek(cur_drv, cur_drv->head, cur_drv->max_track - 1,
2111                 cur_drv->sect, 1);
2112     } else {
2113         fd_seek(cur_drv, cur_drv->head,
2114                 cur_drv->track + fdctrl->fifo[2], cur_drv->sect, 1);
2115     }
2116     fdctrl_to_command_phase(fdctrl);
2117     /* Raise Interrupt */
2118     fdctrl->status0 |= FD_SR0_SEEK;
2119     fdctrl_raise_irq(fdctrl);
2120 }
2121 
2122 static void fdctrl_handle_relative_seek_out(FDCtrl *fdctrl, int direction)
2123 {
2124     FDrive *cur_drv;
2125 
2126     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
2127     cur_drv = get_cur_drv(fdctrl);
2128     if (fdctrl->fifo[2] > cur_drv->track) {
2129         fd_seek(cur_drv, cur_drv->head, 0, cur_drv->sect, 1);
2130     } else {
2131         fd_seek(cur_drv, cur_drv->head,
2132                 cur_drv->track - fdctrl->fifo[2], cur_drv->sect, 1);
2133     }
2134     fdctrl_to_command_phase(fdctrl);
2135     /* Raise Interrupt */
2136     fdctrl->status0 |= FD_SR0_SEEK;
2137     fdctrl_raise_irq(fdctrl);
2138 }
2139 
2140 /*
2141  * Handlers for the execution phase of each command
2142  */
2143 typedef struct FDCtrlCommand {
2144     uint8_t value;
2145     uint8_t mask;
2146     const char* name;
2147     int parameters;
2148     void (*handler)(FDCtrl *fdctrl, int direction);
2149     int direction;
2150 } FDCtrlCommand;
2151 
2152 static const FDCtrlCommand handlers[] = {
2153     { FD_CMD_READ, 0x1f, "READ", 8, fdctrl_start_transfer, FD_DIR_READ },
2154     { FD_CMD_WRITE, 0x3f, "WRITE", 8, fdctrl_start_transfer, FD_DIR_WRITE },
2155     { FD_CMD_SEEK, 0xff, "SEEK", 2, fdctrl_handle_seek },
2156     { FD_CMD_SENSE_INTERRUPT_STATUS, 0xff, "SENSE INTERRUPT STATUS", 0, fdctrl_handle_sense_interrupt_status },
2157     { FD_CMD_RECALIBRATE, 0xff, "RECALIBRATE", 1, fdctrl_handle_recalibrate },
2158     { FD_CMD_FORMAT_TRACK, 0xbf, "FORMAT TRACK", 5, fdctrl_handle_format_track },
2159     { FD_CMD_READ_TRACK, 0xbf, "READ TRACK", 8, fdctrl_start_transfer, FD_DIR_READ },
2160     { FD_CMD_RESTORE, 0xff, "RESTORE", 17, fdctrl_handle_restore }, /* part of READ DELETED DATA */
2161     { FD_CMD_SAVE, 0xff, "SAVE", 0, fdctrl_handle_save }, /* part of READ DELETED DATA */
2162     { FD_CMD_READ_DELETED, 0x1f, "READ DELETED DATA", 8, fdctrl_start_transfer_del, FD_DIR_READ },
2163     { FD_CMD_SCAN_EQUAL, 0x1f, "SCAN EQUAL", 8, fdctrl_start_transfer, FD_DIR_SCANE },
2164     { FD_CMD_VERIFY, 0x1f, "VERIFY", 8, fdctrl_start_transfer, FD_DIR_VERIFY },
2165     { FD_CMD_SCAN_LOW_OR_EQUAL, 0x1f, "SCAN LOW OR EQUAL", 8, fdctrl_start_transfer, FD_DIR_SCANL },
2166     { FD_CMD_SCAN_HIGH_OR_EQUAL, 0x1f, "SCAN HIGH OR EQUAL", 8, fdctrl_start_transfer, FD_DIR_SCANH },
2167     { FD_CMD_WRITE_DELETED, 0x3f, "WRITE DELETED DATA", 8, fdctrl_start_transfer_del, FD_DIR_WRITE },
2168     { FD_CMD_READ_ID, 0xbf, "READ ID", 1, fdctrl_handle_readid },
2169     { FD_CMD_SPECIFY, 0xff, "SPECIFY", 2, fdctrl_handle_specify },
2170     { FD_CMD_SENSE_DRIVE_STATUS, 0xff, "SENSE DRIVE STATUS", 1, fdctrl_handle_sense_drive_status },
2171     { FD_CMD_PERPENDICULAR_MODE, 0xff, "PERPENDICULAR MODE", 1, fdctrl_handle_perpendicular_mode },
2172     { FD_CMD_CONFIGURE, 0xff, "CONFIGURE", 3, fdctrl_handle_configure },
2173     { FD_CMD_POWERDOWN_MODE, 0xff, "POWERDOWN MODE", 2, fdctrl_handle_powerdown_mode },
2174     { FD_CMD_OPTION, 0xff, "OPTION", 1, fdctrl_handle_option },
2175     { FD_CMD_DRIVE_SPECIFICATION_COMMAND, 0xff, "DRIVE SPECIFICATION COMMAND", 5, fdctrl_handle_drive_specification_command },
2176     { FD_CMD_RELATIVE_SEEK_OUT, 0xff, "RELATIVE SEEK OUT", 2, fdctrl_handle_relative_seek_out },
2177     { FD_CMD_FORMAT_AND_WRITE, 0xff, "FORMAT AND WRITE", 10, fdctrl_unimplemented },
2178     { FD_CMD_RELATIVE_SEEK_IN, 0xff, "RELATIVE SEEK IN", 2, fdctrl_handle_relative_seek_in },
2179     { FD_CMD_LOCK, 0x7f, "LOCK", 0, fdctrl_handle_lock },
2180     { FD_CMD_DUMPREG, 0xff, "DUMPREG", 0, fdctrl_handle_dumpreg },
2181     { FD_CMD_VERSION, 0xff, "VERSION", 0, fdctrl_handle_version },
2182     { FD_CMD_PART_ID, 0xff, "PART ID", 0, fdctrl_handle_partid },
2183     { FD_CMD_WRITE, 0x1f, "WRITE (BeOS)", 8, fdctrl_start_transfer, FD_DIR_WRITE }, /* not in specification ; BeOS 4.5 bug */
2184     { 0, 0, "unknown", 0, fdctrl_unimplemented }, /* default handler */
2185 };
2186 /* Associate command to an index in the 'handlers' array */
2187 static uint8_t command_to_handler[256];
2188 
2189 static const FDCtrlCommand *get_command(uint8_t cmd)
2190 {
2191     int idx;
2192 
2193     idx = command_to_handler[cmd];
2194     FLOPPY_DPRINTF("%s command\n", handlers[idx].name);
2195     return &handlers[idx];
2196 }
2197 
2198 static void fdctrl_write_data(FDCtrl *fdctrl, uint32_t value)
2199 {
2200     FDrive *cur_drv;
2201     const FDCtrlCommand *cmd;
2202     uint32_t pos;
2203 
2204     /* Reset mode */
2205     if (!(fdctrl->dor & FD_DOR_nRESET)) {
2206         FLOPPY_DPRINTF("Floppy controller in RESET state !\n");
2207         return;
2208     }
2209     if (!(fdctrl->msr & FD_MSR_RQM) || (fdctrl->msr & FD_MSR_DIO)) {
2210         FLOPPY_DPRINTF("error: controller not ready for writing\n");
2211         return;
2212     }
2213     fdctrl->dsr &= ~FD_DSR_PWRDOWN;
2214 
2215     FLOPPY_DPRINTF("%s: %02x\n", __func__, value);
2216 
2217     /* If data_len spans multiple sectors, the current position in the FIFO
2218      * wraps around while fdctrl->data_pos is the real position in the whole
2219      * request. */
2220     pos = fdctrl->data_pos++;
2221     pos %= FD_SECTOR_LEN;
2222     fdctrl->fifo[pos] = value;
2223 
2224     if (fdctrl->data_pos == fdctrl->data_len) {
2225         fdctrl->msr &= ~FD_MSR_RQM;
2226     }
2227 
2228     switch (fdctrl->phase) {
2229     case FD_PHASE_EXECUTION:
2230         /* For DMA requests, RQM should be cleared during execution phase, so
2231          * we would have errored out above. */
2232         assert(fdctrl->msr & FD_MSR_NONDMA);
2233 
2234         /* FIFO data write */
2235         if (pos == FD_SECTOR_LEN - 1 ||
2236             fdctrl->data_pos == fdctrl->data_len) {
2237             cur_drv = get_cur_drv(fdctrl);
2238             if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv), fdctrl->fifo,
2239                            BDRV_SECTOR_SIZE, 0) < 0) {
2240                 FLOPPY_DPRINTF("error writing sector %d\n",
2241                                fd_sector(cur_drv));
2242                 break;
2243             }
2244             if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv)) {
2245                 FLOPPY_DPRINTF("error seeking to next sector %d\n",
2246                                fd_sector(cur_drv));
2247                 break;
2248             }
2249         }
2250 
2251         /* Switch to result phase when done with the transfer */
2252         if (fdctrl->data_pos == fdctrl->data_len) {
2253             fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
2254         }
2255         break;
2256 
2257     case FD_PHASE_COMMAND:
2258         assert(!(fdctrl->msr & FD_MSR_NONDMA));
2259         assert(fdctrl->data_pos < FD_SECTOR_LEN);
2260 
2261         if (pos == 0) {
2262             /* The first byte specifies the command. Now we start reading
2263              * as many parameters as this command requires. */
2264             cmd = get_command(value);
2265             fdctrl->data_len = cmd->parameters + 1;
2266             if (cmd->parameters) {
2267                 fdctrl->msr |= FD_MSR_RQM;
2268             }
2269             fdctrl->msr |= FD_MSR_CMDBUSY;
2270         }
2271 
2272         if (fdctrl->data_pos == fdctrl->data_len) {
2273             /* We have all parameters now, execute the command */
2274             fdctrl->phase = FD_PHASE_EXECUTION;
2275 
2276             if (fdctrl->data_state & FD_STATE_FORMAT) {
2277                 fdctrl_format_sector(fdctrl);
2278                 break;
2279             }
2280 
2281             cmd = get_command(fdctrl->fifo[0]);
2282             FLOPPY_DPRINTF("Calling handler for '%s'\n", cmd->name);
2283             cmd->handler(fdctrl, cmd->direction);
2284         }
2285         break;
2286 
2287     case FD_PHASE_RESULT:
2288     default:
2289         abort();
2290     }
2291 }
2292 
2293 static void fdctrl_result_timer(void *opaque)
2294 {
2295     FDCtrl *fdctrl = opaque;
2296     FDrive *cur_drv = get_cur_drv(fdctrl);
2297 
2298     /* Pretend we are spinning.
2299      * This is needed for Coherent, which uses READ ID to check for
2300      * sector interleaving.
2301      */
2302     if (cur_drv->last_sect != 0) {
2303         cur_drv->sect = (cur_drv->sect % cur_drv->last_sect) + 1;
2304     }
2305     /* READ_ID can't automatically succeed! */
2306     if ((fdctrl->dsr & FD_DSR_DRATEMASK) != cur_drv->media_rate) {
2307         FLOPPY_DPRINTF("read id rate mismatch (fdc=%d, media=%d)\n",
2308                        fdctrl->dsr & FD_DSR_DRATEMASK, cur_drv->media_rate);
2309         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_MA, 0x00);
2310     } else {
2311         fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
2312     }
2313 }
2314 
2315 /* Init functions */
2316 
2317 void fdctrl_init_drives(FloppyBus *bus, DriveInfo **fds)
2318 {
2319     DeviceState *dev;
2320     int i;
2321 
2322     for (i = 0; i < MAX_FD; i++) {
2323         if (fds[i]) {
2324             dev = qdev_new("floppy");
2325             qdev_prop_set_uint32(dev, "unit", i);
2326             qdev_prop_set_enum(dev, "drive-type", FLOPPY_DRIVE_TYPE_AUTO);
2327             qdev_prop_set_drive_err(dev, "drive", blk_by_legacy_dinfo(fds[i]),
2328                                     &error_fatal);
2329             qdev_realize_and_unref(dev, &bus->bus, &error_fatal);
2330         }
2331     }
2332 }
2333 
2334 void fdctrl_realize_common(DeviceState *dev, FDCtrl *fdctrl, Error **errp)
2335 {
2336     int i, j;
2337     FDrive *drive;
2338     static int command_tables_inited = 0;
2339 
2340     if (fdctrl->fallback == FLOPPY_DRIVE_TYPE_AUTO) {
2341         error_setg(errp, "Cannot choose a fallback FDrive type of 'auto'");
2342         return;
2343     }
2344 
2345     /* Fill 'command_to_handler' lookup table */
2346     if (!command_tables_inited) {
2347         command_tables_inited = 1;
2348         for (i = ARRAY_SIZE(handlers) - 1; i >= 0; i--) {
2349             for (j = 0; j < sizeof(command_to_handler); j++) {
2350                 if ((j & handlers[i].mask) == handlers[i].value) {
2351                     command_to_handler[j] = i;
2352                 }
2353             }
2354         }
2355     }
2356 
2357     FLOPPY_DPRINTF("init controller\n");
2358     fdctrl->fifo = qemu_memalign(512, FD_SECTOR_LEN);
2359     memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
2360     fdctrl->fifo_size = 512;
2361     fdctrl->result_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
2362                                              fdctrl_result_timer, fdctrl);
2363 
2364     fdctrl->version = 0x90; /* Intel 82078 controller */
2365     fdctrl->config = FD_CONFIG_EIS | FD_CONFIG_EFIFO; /* Implicit seek, polling & FIFO enabled */
2366     fdctrl->num_floppies = MAX_FD;
2367 
2368     floppy_bus_create(fdctrl, &fdctrl->bus, dev);
2369 
2370     for (i = 0; i < MAX_FD; i++) {
2371         drive = &fdctrl->drives[i];
2372         drive->fdctrl = fdctrl;
2373         fd_init(drive);
2374         fd_revalidate(drive);
2375     }
2376 }
2377 
2378 static void fdc_register_types(void)
2379 {
2380     type_register_static(&floppy_bus_info);
2381     type_register_static(&floppy_drive_info);
2382 }
2383 
2384 type_init(fdc_register_types)
2385