xref: /openbmc/qemu/hw/block/fdc.c (revision 6fdc5bc1)
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 "qemu/memalign.h"
36 #include "hw/irq.h"
37 #include "hw/isa/isa.h"
38 #include "hw/qdev-properties.h"
39 #include "hw/qdev-properties-system.h"
40 #include "migration/vmstate.h"
41 #include "hw/block/block.h"
42 #include "sysemu/block-backend.h"
43 #include "sysemu/blockdev.h"
44 #include "sysemu/sysemu.h"
45 #include "qemu/log.h"
46 #include "qemu/main-loop.h"
47 #include "qemu/module.h"
48 #include "trace.h"
49 #include "qom/object.h"
50 #include "fdc-internal.h"
51 
52 /********************************************************/
53 /* debug Floppy devices */
54 
55 #define DEBUG_FLOPPY 0
56 
57 #define FLOPPY_DPRINTF(fmt, ...)                                \
58     do {                                                        \
59         if (DEBUG_FLOPPY) {                                     \
60             fprintf(stderr, "FLOPPY: " fmt , ## __VA_ARGS__);   \
61         }                                                       \
62     } while (0)
63 
64 
65 /* Anonymous BlockBackend for empty drive */
66 static BlockBackend *blk_create_empty_drive(void)
67 {
68     return blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL);
69 }
70 
71 /********************************************************/
72 /* qdev floppy bus                                      */
73 
74 #define TYPE_FLOPPY_BUS "floppy-bus"
75 OBJECT_DECLARE_SIMPLE_TYPE(FloppyBus, FLOPPY_BUS)
76 
77 static FDrive *get_drv(FDCtrl *fdctrl, int unit);
78 
79 static const TypeInfo floppy_bus_info = {
80     .name = TYPE_FLOPPY_BUS,
81     .parent = TYPE_BUS,
82     .instance_size = sizeof(FloppyBus),
83 };
84 
85 static void floppy_bus_create(FDCtrl *fdc, FloppyBus *bus, DeviceState *dev)
86 {
87     qbus_init(bus, sizeof(FloppyBus), TYPE_FLOPPY_BUS, dev, NULL);
88     bus->fdc = fdc;
89 }
90 
91 
92 /********************************************************/
93 /* Floppy drive emulation                               */
94 
95 /* In many cases, the total sector size of a format is enough to uniquely
96  * identify it. However, there are some total sector collisions between
97  * formats of different physical size, and these are noted below by
98  * highlighting the total sector size for entries with collisions. */
99 const FDFormat fd_formats[] = {
100     /* First entry is default format */
101     /* 1.44 MB 3"1/2 floppy disks */
102     { FLOPPY_DRIVE_TYPE_144, 18, 80, 1, FDRIVE_RATE_500K, }, /* 3.5" 2880 */
103     { FLOPPY_DRIVE_TYPE_144, 20, 80, 1, FDRIVE_RATE_500K, }, /* 3.5" 3200 */
104     { FLOPPY_DRIVE_TYPE_144, 21, 80, 1, FDRIVE_RATE_500K, },
105     { FLOPPY_DRIVE_TYPE_144, 21, 82, 1, FDRIVE_RATE_500K, },
106     { FLOPPY_DRIVE_TYPE_144, 21, 83, 1, FDRIVE_RATE_500K, },
107     { FLOPPY_DRIVE_TYPE_144, 22, 80, 1, FDRIVE_RATE_500K, },
108     { FLOPPY_DRIVE_TYPE_144, 23, 80, 1, FDRIVE_RATE_500K, },
109     { FLOPPY_DRIVE_TYPE_144, 24, 80, 1, FDRIVE_RATE_500K, },
110     /* 2.88 MB 3"1/2 floppy disks */
111     { FLOPPY_DRIVE_TYPE_288, 36, 80, 1, FDRIVE_RATE_1M, },
112     { FLOPPY_DRIVE_TYPE_288, 39, 80, 1, FDRIVE_RATE_1M, },
113     { FLOPPY_DRIVE_TYPE_288, 40, 80, 1, FDRIVE_RATE_1M, },
114     { FLOPPY_DRIVE_TYPE_288, 44, 80, 1, FDRIVE_RATE_1M, },
115     { FLOPPY_DRIVE_TYPE_288, 48, 80, 1, FDRIVE_RATE_1M, },
116     /* 720 kB 3"1/2 floppy disks */
117     { FLOPPY_DRIVE_TYPE_144,  9, 80, 1, FDRIVE_RATE_250K, }, /* 3.5" 1440 */
118     { FLOPPY_DRIVE_TYPE_144, 10, 80, 1, FDRIVE_RATE_250K, },
119     { FLOPPY_DRIVE_TYPE_144, 10, 82, 1, FDRIVE_RATE_250K, },
120     { FLOPPY_DRIVE_TYPE_144, 10, 83, 1, FDRIVE_RATE_250K, },
121     { FLOPPY_DRIVE_TYPE_144, 13, 80, 1, FDRIVE_RATE_250K, },
122     { FLOPPY_DRIVE_TYPE_144, 14, 80, 1, FDRIVE_RATE_250K, },
123     /* 1.2 MB 5"1/4 floppy disks */
124     { FLOPPY_DRIVE_TYPE_120, 15, 80, 1, FDRIVE_RATE_500K, },
125     { FLOPPY_DRIVE_TYPE_120, 18, 80, 1, FDRIVE_RATE_500K, }, /* 5.25" 2880 */
126     { FLOPPY_DRIVE_TYPE_120, 18, 82, 1, FDRIVE_RATE_500K, },
127     { FLOPPY_DRIVE_TYPE_120, 18, 83, 1, FDRIVE_RATE_500K, },
128     { FLOPPY_DRIVE_TYPE_120, 20, 80, 1, FDRIVE_RATE_500K, }, /* 5.25" 3200 */
129     /* 720 kB 5"1/4 floppy disks */
130     { FLOPPY_DRIVE_TYPE_120,  9, 80, 1, FDRIVE_RATE_250K, }, /* 5.25" 1440 */
131     { FLOPPY_DRIVE_TYPE_120, 11, 80, 1, FDRIVE_RATE_250K, },
132     /* 360 kB 5"1/4 floppy disks */
133     { FLOPPY_DRIVE_TYPE_120,  9, 40, 1, FDRIVE_RATE_300K, }, /* 5.25" 720 */
134     { FLOPPY_DRIVE_TYPE_120,  9, 40, 0, FDRIVE_RATE_300K, },
135     { FLOPPY_DRIVE_TYPE_120, 10, 41, 1, FDRIVE_RATE_300K, },
136     { FLOPPY_DRIVE_TYPE_120, 10, 42, 1, FDRIVE_RATE_300K, },
137     /* 320 kB 5"1/4 floppy disks */
138     { FLOPPY_DRIVE_TYPE_120,  8, 40, 1, FDRIVE_RATE_250K, },
139     { FLOPPY_DRIVE_TYPE_120,  8, 40, 0, FDRIVE_RATE_250K, },
140     /* 360 kB must match 5"1/4 better than 3"1/2... */
141     { FLOPPY_DRIVE_TYPE_144,  9, 80, 0, FDRIVE_RATE_250K, }, /* 3.5" 720 */
142     /* end */
143     { FLOPPY_DRIVE_TYPE_NONE, -1, -1, 0, 0, },
144 };
145 
146 static FDriveSize drive_size(FloppyDriveType drive)
147 {
148     switch (drive) {
149     case FLOPPY_DRIVE_TYPE_120:
150         return FDRIVE_SIZE_525;
151     case FLOPPY_DRIVE_TYPE_144:
152     case FLOPPY_DRIVE_TYPE_288:
153         return FDRIVE_SIZE_350;
154     default:
155         return FDRIVE_SIZE_UNKNOWN;
156     }
157 }
158 
159 #define GET_CUR_DRV(fdctrl) ((fdctrl)->cur_drv)
160 #define SET_CUR_DRV(fdctrl, drive) ((fdctrl)->cur_drv = (drive))
161 
162 /* Will always be a fixed parameter for us */
163 #define FD_SECTOR_LEN          512
164 #define FD_SECTOR_SC           2   /* Sector size code */
165 #define FD_RESET_SENSEI_COUNT  4   /* Number of sense interrupts on RESET */
166 
167 
168 static FloppyDriveType get_fallback_drive_type(FDrive *drv);
169 
170 /* Hack: FD_SEEK is expected to work on empty drives. However, QEMU
171  * currently goes through some pains to keep seeks within the bounds
172  * established by last_sect and max_track. Correcting this is difficult,
173  * as refactoring FDC code tends to expose nasty bugs in the Linux kernel.
174  *
175  * For now: allow empty drives to have large bounds so we can seek around,
176  * with the understanding that when a diskette is inserted, the bounds will
177  * properly tighten to match the geometry of that inserted medium.
178  */
179 static void fd_empty_seek_hack(FDrive *drv)
180 {
181     drv->last_sect = 0xFF;
182     drv->max_track = 0xFF;
183 }
184 
185 static void fd_init(FDrive *drv)
186 {
187     /* Drive */
188     drv->perpendicular = 0;
189     /* Disk */
190     drv->disk = FLOPPY_DRIVE_TYPE_NONE;
191     drv->last_sect = 0;
192     drv->max_track = 0;
193     drv->ro = true;
194     drv->media_changed = 1;
195 }
196 
197 #define NUM_SIDES(drv) ((drv)->flags & FDISK_DBL_SIDES ? 2 : 1)
198 
199 static int fd_sector_calc(uint8_t head, uint8_t track, uint8_t sect,
200                           uint8_t last_sect, uint8_t num_sides)
201 {
202     return (((track * num_sides) + head) * last_sect) + sect - 1;
203 }
204 
205 /* Returns current position, in sectors, for given drive */
206 static int fd_sector(FDrive *drv)
207 {
208     return fd_sector_calc(drv->head, drv->track, drv->sect, drv->last_sect,
209                           NUM_SIDES(drv));
210 }
211 
212 /* Returns current position, in bytes, for given drive */
213 static int fd_offset(FDrive *drv)
214 {
215     g_assert(fd_sector(drv) < INT_MAX >> BDRV_SECTOR_BITS);
216     return fd_sector(drv) << BDRV_SECTOR_BITS;
217 }
218 
219 /* Seek to a new position:
220  * returns 0 if already on right track
221  * returns 1 if track changed
222  * returns 2 if track is invalid
223  * returns 3 if sector is invalid
224  * returns 4 if seek is disabled
225  */
226 static int fd_seek(FDrive *drv, uint8_t head, uint8_t track, uint8_t sect,
227                    int enable_seek)
228 {
229     uint32_t sector;
230     int ret;
231 
232     if (track > drv->max_track ||
233         (head != 0 && (drv->flags & FDISK_DBL_SIDES) == 0)) {
234         FLOPPY_DPRINTF("try to read %d %02x %02x (max=%d %d %02x %02x)\n",
235                        head, track, sect, 1,
236                        (drv->flags & FDISK_DBL_SIDES) == 0 ? 0 : 1,
237                        drv->max_track, drv->last_sect);
238         return 2;
239     }
240     if (sect > drv->last_sect) {
241         FLOPPY_DPRINTF("try to read %d %02x %02x (max=%d %d %02x %02x)\n",
242                        head, track, sect, 1,
243                        (drv->flags & FDISK_DBL_SIDES) == 0 ? 0 : 1,
244                        drv->max_track, drv->last_sect);
245         return 3;
246     }
247     sector = fd_sector_calc(head, track, sect, drv->last_sect, NUM_SIDES(drv));
248     ret = 0;
249     if (sector != fd_sector(drv)) {
250 #if 0
251         if (!enable_seek) {
252             FLOPPY_DPRINTF("error: no implicit seek %d %02x %02x"
253                            " (max=%d %02x %02x)\n",
254                            head, track, sect, 1, drv->max_track,
255                            drv->last_sect);
256             return 4;
257         }
258 #endif
259         drv->head = head;
260         if (drv->track != track) {
261             if (drv->blk != NULL && blk_is_inserted(drv->blk)) {
262                 drv->media_changed = 0;
263             }
264             ret = 1;
265         }
266         drv->track = track;
267         drv->sect = sect;
268     }
269 
270     if (drv->blk == NULL || !blk_is_inserted(drv->blk)) {
271         ret = 2;
272     }
273 
274     return ret;
275 }
276 
277 /* Set drive back to track 0 */
278 static void fd_recalibrate(FDrive *drv)
279 {
280     FLOPPY_DPRINTF("recalibrate\n");
281     fd_seek(drv, 0, 0, 1, 1);
282 }
283 
284 /**
285  * Determine geometry based on inserted diskette.
286  * Will not operate on an empty drive.
287  *
288  * @return: 0 on success, -1 if the drive is empty.
289  */
290 static int pick_geometry(FDrive *drv)
291 {
292     BlockBackend *blk = drv->blk;
293     const FDFormat *parse;
294     uint64_t nb_sectors, size;
295     int i;
296     int match, size_match, type_match;
297     bool magic = drv->drive == FLOPPY_DRIVE_TYPE_AUTO;
298 
299     /* We can only pick a geometry if we have a diskette. */
300     if (!drv->blk || !blk_is_inserted(drv->blk) ||
301         drv->drive == FLOPPY_DRIVE_TYPE_NONE)
302     {
303         return -1;
304     }
305 
306     /* We need to determine the likely geometry of the inserted medium.
307      * In order of preference, we look for:
308      * (1) The same drive type and number of sectors,
309      * (2) The same diskette size and number of sectors,
310      * (3) The same drive type.
311      *
312      * In all cases, matches that occur higher in the drive table will take
313      * precedence over matches that occur later in the table.
314      */
315     blk_get_geometry(blk, &nb_sectors);
316     match = size_match = type_match = -1;
317     for (i = 0; ; i++) {
318         parse = &fd_formats[i];
319         if (parse->drive == FLOPPY_DRIVE_TYPE_NONE) {
320             break;
321         }
322         size = (parse->max_head + 1) * parse->max_track * parse->last_sect;
323         if (nb_sectors == size) {
324             if (magic || parse->drive == drv->drive) {
325                 /* (1) perfect match -- nb_sectors and drive type */
326                 goto out;
327             } else if (drive_size(parse->drive) == drive_size(drv->drive)) {
328                 /* (2) size match -- nb_sectors and physical medium size */
329                 match = (match == -1) ? i : match;
330             } else {
331                 /* This is suspicious -- Did the user misconfigure? */
332                 size_match = (size_match == -1) ? i : size_match;
333             }
334         } else if (type_match == -1) {
335             if ((parse->drive == drv->drive) ||
336                 (magic && (parse->drive == get_fallback_drive_type(drv)))) {
337                 /* (3) type match -- nb_sectors mismatch, but matches the type
338                  *     specified explicitly by the user, or matches the fallback
339                  *     default type when using the drive autodetect mechanism */
340                 type_match = i;
341             }
342         }
343     }
344 
345     /* No exact match found */
346     if (match == -1) {
347         if (size_match != -1) {
348             parse = &fd_formats[size_match];
349             FLOPPY_DPRINTF("User requested floppy drive type '%s', "
350                            "but inserted medium appears to be a "
351                            "%"PRId64" sector '%s' type\n",
352                            FloppyDriveType_str(drv->drive),
353                            nb_sectors,
354                            FloppyDriveType_str(parse->drive));
355         }
356         assert(type_match != -1 && "misconfigured fd_format");
357         match = type_match;
358     }
359     parse = &(fd_formats[match]);
360 
361  out:
362     if (parse->max_head == 0) {
363         drv->flags &= ~FDISK_DBL_SIDES;
364     } else {
365         drv->flags |= FDISK_DBL_SIDES;
366     }
367     drv->max_track = parse->max_track;
368     drv->last_sect = parse->last_sect;
369     drv->disk = parse->drive;
370     drv->media_rate = parse->rate;
371     return 0;
372 }
373 
374 static void pick_drive_type(FDrive *drv)
375 {
376     if (drv->drive != FLOPPY_DRIVE_TYPE_AUTO) {
377         return;
378     }
379 
380     if (pick_geometry(drv) == 0) {
381         drv->drive = drv->disk;
382     } else {
383         drv->drive = get_fallback_drive_type(drv);
384     }
385 
386     g_assert(drv->drive != FLOPPY_DRIVE_TYPE_AUTO);
387 }
388 
389 /* Revalidate a disk drive after a disk change */
390 static void fd_revalidate(FDrive *drv)
391 {
392     int rc;
393 
394     FLOPPY_DPRINTF("revalidate\n");
395     if (drv->blk != NULL) {
396         drv->ro = !blk_is_writable(drv->blk);
397         if (!blk_is_inserted(drv->blk)) {
398             FLOPPY_DPRINTF("No disk in drive\n");
399             drv->disk = FLOPPY_DRIVE_TYPE_NONE;
400             fd_empty_seek_hack(drv);
401         } else if (!drv->media_validated) {
402             rc = pick_geometry(drv);
403             if (rc) {
404                 FLOPPY_DPRINTF("Could not validate floppy drive media");
405             } else {
406                 drv->media_validated = true;
407                 FLOPPY_DPRINTF("Floppy disk (%d h %d t %d s) %s\n",
408                                (drv->flags & FDISK_DBL_SIDES) ? 2 : 1,
409                                drv->max_track, drv->last_sect,
410                                drv->ro ? "ro" : "rw");
411             }
412         }
413     } else {
414         FLOPPY_DPRINTF("No drive connected\n");
415         drv->last_sect = 0;
416         drv->max_track = 0;
417         drv->flags &= ~FDISK_DBL_SIDES;
418         drv->drive = FLOPPY_DRIVE_TYPE_NONE;
419         drv->disk = FLOPPY_DRIVE_TYPE_NONE;
420     }
421 }
422 
423 static void fd_change_cb(void *opaque, bool load, Error **errp)
424 {
425     FDrive *drive = opaque;
426 
427     if (!load) {
428         blk_set_perm(drive->blk, 0, BLK_PERM_ALL, &error_abort);
429     } else {
430         if (!blkconf_apply_backend_options(drive->conf,
431                                            !blk_supports_write_perm(drive->blk),
432                                            false, errp)) {
433             return;
434         }
435     }
436 
437     drive->media_changed = 1;
438     drive->media_validated = false;
439     fd_revalidate(drive);
440 }
441 
442 static const BlockDevOps fd_block_ops = {
443     .change_media_cb = fd_change_cb,
444 };
445 
446 
447 #define TYPE_FLOPPY_DRIVE "floppy"
448 OBJECT_DECLARE_SIMPLE_TYPE(FloppyDrive, FLOPPY_DRIVE)
449 
450 struct FloppyDrive {
451     DeviceState     qdev;
452     uint32_t        unit;
453     BlockConf       conf;
454     FloppyDriveType type;
455 };
456 
457 static Property floppy_drive_properties[] = {
458     DEFINE_PROP_UINT32("unit", FloppyDrive, unit, -1),
459     DEFINE_BLOCK_PROPERTIES(FloppyDrive, conf),
460     DEFINE_PROP_SIGNED("drive-type", FloppyDrive, type,
461                         FLOPPY_DRIVE_TYPE_AUTO, qdev_prop_fdc_drive_type,
462                         FloppyDriveType),
463     DEFINE_PROP_END_OF_LIST(),
464 };
465 
466 static void floppy_drive_realize(DeviceState *qdev, Error **errp)
467 {
468     FloppyDrive *dev = FLOPPY_DRIVE(qdev);
469     FloppyBus *bus = FLOPPY_BUS(qdev->parent_bus);
470     FDrive *drive;
471     bool read_only;
472     int ret;
473 
474     if (dev->unit == -1) {
475         for (dev->unit = 0; dev->unit < MAX_FD; dev->unit++) {
476             drive = get_drv(bus->fdc, dev->unit);
477             if (!drive->blk) {
478                 break;
479             }
480         }
481     }
482 
483     if (dev->unit >= MAX_FD) {
484         error_setg(errp, "Can't create floppy unit %d, bus supports "
485                    "only %d units", dev->unit, MAX_FD);
486         return;
487     }
488 
489     drive = get_drv(bus->fdc, dev->unit);
490     if (drive->blk) {
491         error_setg(errp, "Floppy unit %d is in use", dev->unit);
492         return;
493     }
494 
495     if (!dev->conf.blk) {
496         dev->conf.blk = blk_create_empty_drive();
497         ret = blk_attach_dev(dev->conf.blk, qdev);
498         assert(ret == 0);
499 
500         /* Don't take write permissions on an empty drive to allow attaching a
501          * read-only node later */
502         read_only = true;
503     } else {
504         read_only = !blk_bs(dev->conf.blk) ||
505                     !blk_supports_write_perm(dev->conf.blk);
506     }
507 
508     if (!blkconf_blocksizes(&dev->conf, errp)) {
509         return;
510     }
511 
512     if (dev->conf.logical_block_size != 512 ||
513         dev->conf.physical_block_size != 512)
514     {
515         error_setg(errp, "Physical and logical block size must "
516                    "be 512 for floppy");
517         return;
518     }
519 
520     /* rerror/werror aren't supported by fdc and therefore not even registered
521      * with qdev. So set the defaults manually before they are used in
522      * blkconf_apply_backend_options(). */
523     dev->conf.rerror = BLOCKDEV_ON_ERROR_AUTO;
524     dev->conf.werror = BLOCKDEV_ON_ERROR_AUTO;
525 
526     if (!blkconf_apply_backend_options(&dev->conf, read_only, false, errp)) {
527         return;
528     }
529 
530     /* 'enospc' is the default for -drive, 'report' is what blk_new() gives us
531      * for empty drives. */
532     if (blk_get_on_error(dev->conf.blk, 0) != BLOCKDEV_ON_ERROR_ENOSPC &&
533         blk_get_on_error(dev->conf.blk, 0) != BLOCKDEV_ON_ERROR_REPORT) {
534         error_setg(errp, "fdc doesn't support drive option werror");
535         return;
536     }
537     if (blk_get_on_error(dev->conf.blk, 1) != BLOCKDEV_ON_ERROR_REPORT) {
538         error_setg(errp, "fdc doesn't support drive option rerror");
539         return;
540     }
541 
542     drive->conf = &dev->conf;
543     drive->blk = dev->conf.blk;
544     drive->fdctrl = bus->fdc;
545 
546     fd_init(drive);
547     blk_set_dev_ops(drive->blk, &fd_block_ops, drive);
548 
549     /* Keep 'type' qdev property and FDrive->drive in sync */
550     drive->drive = dev->type;
551     pick_drive_type(drive);
552     dev->type = drive->drive;
553 
554     fd_revalidate(drive);
555 }
556 
557 static void floppy_drive_class_init(ObjectClass *klass, void *data)
558 {
559     DeviceClass *k = DEVICE_CLASS(klass);
560     k->realize = floppy_drive_realize;
561     set_bit(DEVICE_CATEGORY_STORAGE, k->categories);
562     k->bus_type = TYPE_FLOPPY_BUS;
563     device_class_set_props(k, floppy_drive_properties);
564     k->desc = "virtual floppy drive";
565 }
566 
567 static const TypeInfo floppy_drive_info = {
568     .name = TYPE_FLOPPY_DRIVE,
569     .parent = TYPE_DEVICE,
570     .instance_size = sizeof(FloppyDrive),
571     .class_init = floppy_drive_class_init,
572 };
573 
574 /********************************************************/
575 /* Intel 82078 floppy disk controller emulation          */
576 
577 static void fdctrl_to_command_phase(FDCtrl *fdctrl);
578 static void fdctrl_raise_irq(FDCtrl *fdctrl);
579 static FDrive *get_cur_drv(FDCtrl *fdctrl);
580 
581 static uint32_t fdctrl_read_statusA(FDCtrl *fdctrl);
582 static uint32_t fdctrl_read_statusB(FDCtrl *fdctrl);
583 static uint32_t fdctrl_read_dor(FDCtrl *fdctrl);
584 static void fdctrl_write_dor(FDCtrl *fdctrl, uint32_t value);
585 static uint32_t fdctrl_read_tape(FDCtrl *fdctrl);
586 static void fdctrl_write_tape(FDCtrl *fdctrl, uint32_t value);
587 static uint32_t fdctrl_read_main_status(FDCtrl *fdctrl);
588 static void fdctrl_write_rate(FDCtrl *fdctrl, uint32_t value);
589 static uint32_t fdctrl_read_data(FDCtrl *fdctrl);
590 static void fdctrl_write_data(FDCtrl *fdctrl, uint32_t value);
591 static uint32_t fdctrl_read_dir(FDCtrl *fdctrl);
592 static void fdctrl_write_ccr(FDCtrl *fdctrl, uint32_t value);
593 
594 enum {
595     FD_DIR_WRITE   = 0,
596     FD_DIR_READ    = 1,
597     FD_DIR_SCANE   = 2,
598     FD_DIR_SCANL   = 3,
599     FD_DIR_SCANH   = 4,
600     FD_DIR_VERIFY  = 5,
601 };
602 
603 enum {
604     FD_STATE_MULTI  = 0x01, /* multi track flag */
605     FD_STATE_FORMAT = 0x02, /* format flag */
606 };
607 
608 enum {
609     FD_REG_SRA = 0x00,
610     FD_REG_SRB = 0x01,
611     FD_REG_DOR = 0x02,
612     FD_REG_TDR = 0x03,
613     FD_REG_MSR = 0x04,
614     FD_REG_DSR = 0x04,
615     FD_REG_FIFO = 0x05,
616     FD_REG_DIR = 0x07,
617     FD_REG_CCR = 0x07,
618 };
619 
620 enum {
621     FD_CMD_READ_TRACK = 0x02,
622     FD_CMD_SPECIFY = 0x03,
623     FD_CMD_SENSE_DRIVE_STATUS = 0x04,
624     FD_CMD_WRITE = 0x05,
625     FD_CMD_READ = 0x06,
626     FD_CMD_RECALIBRATE = 0x07,
627     FD_CMD_SENSE_INTERRUPT_STATUS = 0x08,
628     FD_CMD_WRITE_DELETED = 0x09,
629     FD_CMD_READ_ID = 0x0a,
630     FD_CMD_READ_DELETED = 0x0c,
631     FD_CMD_FORMAT_TRACK = 0x0d,
632     FD_CMD_DUMPREG = 0x0e,
633     FD_CMD_SEEK = 0x0f,
634     FD_CMD_VERSION = 0x10,
635     FD_CMD_SCAN_EQUAL = 0x11,
636     FD_CMD_PERPENDICULAR_MODE = 0x12,
637     FD_CMD_CONFIGURE = 0x13,
638     FD_CMD_LOCK = 0x14,
639     FD_CMD_VERIFY = 0x16,
640     FD_CMD_POWERDOWN_MODE = 0x17,
641     FD_CMD_PART_ID = 0x18,
642     FD_CMD_SCAN_LOW_OR_EQUAL = 0x19,
643     FD_CMD_SCAN_HIGH_OR_EQUAL = 0x1d,
644     FD_CMD_SAVE = 0x2e,
645     FD_CMD_OPTION = 0x33,
646     FD_CMD_RESTORE = 0x4e,
647     FD_CMD_DRIVE_SPECIFICATION_COMMAND = 0x8e,
648     FD_CMD_RELATIVE_SEEK_OUT = 0x8f,
649     FD_CMD_FORMAT_AND_WRITE = 0xcd,
650     FD_CMD_RELATIVE_SEEK_IN = 0xcf,
651 };
652 
653 enum {
654     FD_CONFIG_PRETRK = 0xff, /* Pre-compensation set to track 0 */
655     FD_CONFIG_FIFOTHR = 0x0f, /* FIFO threshold set to 1 byte */
656     FD_CONFIG_POLL  = 0x10, /* Poll enabled */
657     FD_CONFIG_EFIFO = 0x20, /* FIFO disabled */
658     FD_CONFIG_EIS   = 0x40, /* No implied seeks */
659 };
660 
661 enum {
662     FD_SR0_DS0      = 0x01,
663     FD_SR0_DS1      = 0x02,
664     FD_SR0_HEAD     = 0x04,
665     FD_SR0_EQPMT    = 0x10,
666     FD_SR0_SEEK     = 0x20,
667     FD_SR0_ABNTERM  = 0x40,
668     FD_SR0_INVCMD   = 0x80,
669     FD_SR0_RDYCHG   = 0xc0,
670 };
671 
672 enum {
673     FD_SR1_MA       = 0x01, /* Missing address mark */
674     FD_SR1_NW       = 0x02, /* Not writable */
675     FD_SR1_EC       = 0x80, /* End of cylinder */
676 };
677 
678 enum {
679     FD_SR2_SNS      = 0x04, /* Scan not satisfied */
680     FD_SR2_SEH      = 0x08, /* Scan equal hit */
681 };
682 
683 enum {
684     FD_SRA_DIR      = 0x01,
685     FD_SRA_nWP      = 0x02,
686     FD_SRA_nINDX    = 0x04,
687     FD_SRA_HDSEL    = 0x08,
688     FD_SRA_nTRK0    = 0x10,
689     FD_SRA_STEP     = 0x20,
690     FD_SRA_nDRV2    = 0x40,
691     FD_SRA_INTPEND  = 0x80,
692 };
693 
694 enum {
695     FD_SRB_MTR0     = 0x01,
696     FD_SRB_MTR1     = 0x02,
697     FD_SRB_WGATE    = 0x04,
698     FD_SRB_RDATA    = 0x08,
699     FD_SRB_WDATA    = 0x10,
700     FD_SRB_DR0      = 0x20,
701 };
702 
703 enum {
704 #if MAX_FD == 4
705     FD_DOR_SELMASK  = 0x03,
706 #else
707     FD_DOR_SELMASK  = 0x01,
708 #endif
709     FD_DOR_nRESET   = 0x04,
710     FD_DOR_DMAEN    = 0x08,
711     FD_DOR_MOTEN0   = 0x10,
712     FD_DOR_MOTEN1   = 0x20,
713     FD_DOR_MOTEN2   = 0x40,
714     FD_DOR_MOTEN3   = 0x80,
715 };
716 
717 enum {
718 #if MAX_FD == 4
719     FD_TDR_BOOTSEL  = 0x0c,
720 #else
721     FD_TDR_BOOTSEL  = 0x04,
722 #endif
723 };
724 
725 enum {
726     FD_DSR_DRATEMASK= 0x03,
727     FD_DSR_PWRDOWN  = 0x40,
728     FD_DSR_SWRESET  = 0x80,
729 };
730 
731 enum {
732     FD_MSR_DRV0BUSY = 0x01,
733     FD_MSR_DRV1BUSY = 0x02,
734     FD_MSR_DRV2BUSY = 0x04,
735     FD_MSR_DRV3BUSY = 0x08,
736     FD_MSR_CMDBUSY  = 0x10,
737     FD_MSR_NONDMA   = 0x20,
738     FD_MSR_DIO      = 0x40,
739     FD_MSR_RQM      = 0x80,
740 };
741 
742 enum {
743     FD_DIR_DSKCHG   = 0x80,
744 };
745 
746 /*
747  * See chapter 5.0 "Controller phases" of the spec:
748  *
749  * Command phase:
750  * The host writes a command and its parameters into the FIFO. The command
751  * phase is completed when all parameters for the command have been supplied,
752  * and execution phase is entered.
753  *
754  * Execution phase:
755  * Data transfers, either DMA or non-DMA. For non-DMA transfers, the FIFO
756  * contains the payload now, otherwise it's unused. When all bytes of the
757  * required data have been transferred, the state is switched to either result
758  * phase (if the command produces status bytes) or directly back into the
759  * command phase for the next command.
760  *
761  * Result phase:
762  * The host reads out the FIFO, which contains one or more result bytes now.
763  */
764 enum {
765     /* Only for migration: reconstruct phase from registers like qemu 2.3 */
766     FD_PHASE_RECONSTRUCT    = 0,
767 
768     FD_PHASE_COMMAND        = 1,
769     FD_PHASE_EXECUTION      = 2,
770     FD_PHASE_RESULT         = 3,
771 };
772 
773 #define FD_MULTI_TRACK(state) ((state) & FD_STATE_MULTI)
774 #define FD_FORMAT_CMD(state) ((state) & FD_STATE_FORMAT)
775 
776 static FloppyDriveType get_fallback_drive_type(FDrive *drv)
777 {
778     return drv->fdctrl->fallback;
779 }
780 
781 uint32_t fdctrl_read(void *opaque, uint32_t reg)
782 {
783     FDCtrl *fdctrl = opaque;
784     uint32_t retval;
785 
786     reg &= 7;
787     switch (reg) {
788     case FD_REG_SRA:
789         retval = fdctrl_read_statusA(fdctrl);
790         break;
791     case FD_REG_SRB:
792         retval = fdctrl_read_statusB(fdctrl);
793         break;
794     case FD_REG_DOR:
795         retval = fdctrl_read_dor(fdctrl);
796         break;
797     case FD_REG_TDR:
798         retval = fdctrl_read_tape(fdctrl);
799         break;
800     case FD_REG_MSR:
801         retval = fdctrl_read_main_status(fdctrl);
802         break;
803     case FD_REG_FIFO:
804         retval = fdctrl_read_data(fdctrl);
805         break;
806     case FD_REG_DIR:
807         retval = fdctrl_read_dir(fdctrl);
808         break;
809     default:
810         retval = (uint32_t)(-1);
811         break;
812     }
813     trace_fdc_ioport_read(reg, retval);
814 
815     return retval;
816 }
817 
818 void fdctrl_write(void *opaque, uint32_t reg, uint32_t value)
819 {
820     FDCtrl *fdctrl = opaque;
821 
822     reg &= 7;
823     trace_fdc_ioport_write(reg, value);
824     switch (reg) {
825     case FD_REG_DOR:
826         fdctrl_write_dor(fdctrl, value);
827         break;
828     case FD_REG_TDR:
829         fdctrl_write_tape(fdctrl, value);
830         break;
831     case FD_REG_DSR:
832         fdctrl_write_rate(fdctrl, value);
833         break;
834     case FD_REG_FIFO:
835         fdctrl_write_data(fdctrl, value);
836         break;
837     case FD_REG_CCR:
838         fdctrl_write_ccr(fdctrl, value);
839         break;
840     default:
841         break;
842     }
843 }
844 
845 static bool fdrive_media_changed_needed(void *opaque)
846 {
847     FDrive *drive = opaque;
848 
849     return (drive->blk != NULL && drive->media_changed != 1);
850 }
851 
852 static const VMStateDescription vmstate_fdrive_media_changed = {
853     .name = "fdrive/media_changed",
854     .version_id = 1,
855     .minimum_version_id = 1,
856     .needed = fdrive_media_changed_needed,
857     .fields = (const VMStateField[]) {
858         VMSTATE_UINT8(media_changed, FDrive),
859         VMSTATE_END_OF_LIST()
860     }
861 };
862 
863 static const VMStateDescription vmstate_fdrive_media_rate = {
864     .name = "fdrive/media_rate",
865     .version_id = 1,
866     .minimum_version_id = 1,
867     .fields = (const VMStateField[]) {
868         VMSTATE_UINT8(media_rate, FDrive),
869         VMSTATE_END_OF_LIST()
870     }
871 };
872 
873 static bool fdrive_perpendicular_needed(void *opaque)
874 {
875     FDrive *drive = opaque;
876 
877     return drive->perpendicular != 0;
878 }
879 
880 static const VMStateDescription vmstate_fdrive_perpendicular = {
881     .name = "fdrive/perpendicular",
882     .version_id = 1,
883     .minimum_version_id = 1,
884     .needed = fdrive_perpendicular_needed,
885     .fields = (const VMStateField[]) {
886         VMSTATE_UINT8(perpendicular, FDrive),
887         VMSTATE_END_OF_LIST()
888     }
889 };
890 
891 static int fdrive_post_load(void *opaque, int version_id)
892 {
893     fd_revalidate(opaque);
894     return 0;
895 }
896 
897 static const VMStateDescription vmstate_fdrive = {
898     .name = "fdrive",
899     .version_id = 1,
900     .minimum_version_id = 1,
901     .post_load = fdrive_post_load,
902     .fields = (const VMStateField[]) {
903         VMSTATE_UINT8(head, FDrive),
904         VMSTATE_UINT8(track, FDrive),
905         VMSTATE_UINT8(sect, FDrive),
906         VMSTATE_END_OF_LIST()
907     },
908     .subsections = (const VMStateDescription * const []) {
909         &vmstate_fdrive_media_changed,
910         &vmstate_fdrive_media_rate,
911         &vmstate_fdrive_perpendicular,
912         NULL
913     }
914 };
915 
916 /*
917  * Reconstructs the phase from register values according to the logic that was
918  * implemented in qemu 2.3. This is the default value that is used if the phase
919  * subsection is not present on migration.
920  *
921  * Don't change this function to reflect newer qemu versions, it is part of
922  * the migration ABI.
923  */
924 static int reconstruct_phase(FDCtrl *fdctrl)
925 {
926     if (fdctrl->msr & FD_MSR_NONDMA) {
927         return FD_PHASE_EXECUTION;
928     } else if ((fdctrl->msr & FD_MSR_RQM) == 0) {
929         /* qemu 2.3 disabled RQM only during DMA transfers */
930         return FD_PHASE_EXECUTION;
931     } else if (fdctrl->msr & FD_MSR_DIO) {
932         return FD_PHASE_RESULT;
933     } else {
934         return FD_PHASE_COMMAND;
935     }
936 }
937 
938 static int fdc_pre_save(void *opaque)
939 {
940     FDCtrl *s = opaque;
941 
942     s->dor_vmstate = s->dor | GET_CUR_DRV(s);
943 
944     return 0;
945 }
946 
947 static int fdc_pre_load(void *opaque)
948 {
949     FDCtrl *s = opaque;
950     s->phase = FD_PHASE_RECONSTRUCT;
951     return 0;
952 }
953 
954 static int fdc_post_load(void *opaque, int version_id)
955 {
956     FDCtrl *s = opaque;
957 
958     SET_CUR_DRV(s, s->dor_vmstate & FD_DOR_SELMASK);
959     s->dor = s->dor_vmstate & ~FD_DOR_SELMASK;
960 
961     if (s->phase == FD_PHASE_RECONSTRUCT) {
962         s->phase = reconstruct_phase(s);
963     }
964 
965     return 0;
966 }
967 
968 static bool fdc_reset_sensei_needed(void *opaque)
969 {
970     FDCtrl *s = opaque;
971 
972     return s->reset_sensei != 0;
973 }
974 
975 static const VMStateDescription vmstate_fdc_reset_sensei = {
976     .name = "fdc/reset_sensei",
977     .version_id = 1,
978     .minimum_version_id = 1,
979     .needed = fdc_reset_sensei_needed,
980     .fields = (const VMStateField[]) {
981         VMSTATE_INT32(reset_sensei, FDCtrl),
982         VMSTATE_END_OF_LIST()
983     }
984 };
985 
986 static bool fdc_result_timer_needed(void *opaque)
987 {
988     FDCtrl *s = opaque;
989 
990     return timer_pending(s->result_timer);
991 }
992 
993 static const VMStateDescription vmstate_fdc_result_timer = {
994     .name = "fdc/result_timer",
995     .version_id = 1,
996     .minimum_version_id = 1,
997     .needed = fdc_result_timer_needed,
998     .fields = (const VMStateField[]) {
999         VMSTATE_TIMER_PTR(result_timer, FDCtrl),
1000         VMSTATE_END_OF_LIST()
1001     }
1002 };
1003 
1004 static bool fdc_phase_needed(void *opaque)
1005 {
1006     FDCtrl *fdctrl = opaque;
1007 
1008     return reconstruct_phase(fdctrl) != fdctrl->phase;
1009 }
1010 
1011 static const VMStateDescription vmstate_fdc_phase = {
1012     .name = "fdc/phase",
1013     .version_id = 1,
1014     .minimum_version_id = 1,
1015     .needed = fdc_phase_needed,
1016     .fields = (const VMStateField[]) {
1017         VMSTATE_UINT8(phase, FDCtrl),
1018         VMSTATE_END_OF_LIST()
1019     }
1020 };
1021 
1022 const VMStateDescription vmstate_fdc = {
1023     .name = "fdc",
1024     .version_id = 2,
1025     .minimum_version_id = 2,
1026     .pre_save = fdc_pre_save,
1027     .pre_load = fdc_pre_load,
1028     .post_load = fdc_post_load,
1029     .fields = (const VMStateField[]) {
1030         /* Controller State */
1031         VMSTATE_UINT8(sra, FDCtrl),
1032         VMSTATE_UINT8(srb, FDCtrl),
1033         VMSTATE_UINT8(dor_vmstate, FDCtrl),
1034         VMSTATE_UINT8(tdr, FDCtrl),
1035         VMSTATE_UINT8(dsr, FDCtrl),
1036         VMSTATE_UINT8(msr, FDCtrl),
1037         VMSTATE_UINT8(status0, FDCtrl),
1038         VMSTATE_UINT8(status1, FDCtrl),
1039         VMSTATE_UINT8(status2, FDCtrl),
1040         /* Command FIFO */
1041         VMSTATE_VARRAY_INT32(fifo, FDCtrl, fifo_size, 0, vmstate_info_uint8,
1042                              uint8_t),
1043         VMSTATE_UINT32(data_pos, FDCtrl),
1044         VMSTATE_UINT32(data_len, FDCtrl),
1045         VMSTATE_UINT8(data_state, FDCtrl),
1046         VMSTATE_UINT8(data_dir, FDCtrl),
1047         VMSTATE_UINT8(eot, FDCtrl),
1048         /* States kept only to be returned back */
1049         VMSTATE_UINT8(timer0, FDCtrl),
1050         VMSTATE_UINT8(timer1, FDCtrl),
1051         VMSTATE_UINT8(precomp_trk, FDCtrl),
1052         VMSTATE_UINT8(config, FDCtrl),
1053         VMSTATE_UINT8(lock, FDCtrl),
1054         VMSTATE_UINT8(pwrd, FDCtrl),
1055         VMSTATE_UINT8_EQUAL(num_floppies, FDCtrl, NULL),
1056         VMSTATE_STRUCT_ARRAY(drives, FDCtrl, MAX_FD, 1,
1057                              vmstate_fdrive, FDrive),
1058         VMSTATE_END_OF_LIST()
1059     },
1060     .subsections = (const VMStateDescription * const []) {
1061         &vmstate_fdc_reset_sensei,
1062         &vmstate_fdc_result_timer,
1063         &vmstate_fdc_phase,
1064         NULL
1065     }
1066 };
1067 
1068 /* Change IRQ state */
1069 static void fdctrl_reset_irq(FDCtrl *fdctrl)
1070 {
1071     fdctrl->status0 = 0;
1072     if (!(fdctrl->sra & FD_SRA_INTPEND))
1073         return;
1074     FLOPPY_DPRINTF("Reset interrupt\n");
1075     qemu_set_irq(fdctrl->irq, 0);
1076     fdctrl->sra &= ~FD_SRA_INTPEND;
1077 }
1078 
1079 static void fdctrl_raise_irq(FDCtrl *fdctrl)
1080 {
1081     if (!(fdctrl->sra & FD_SRA_INTPEND)) {
1082         qemu_set_irq(fdctrl->irq, 1);
1083         fdctrl->sra |= FD_SRA_INTPEND;
1084     }
1085 
1086     fdctrl->reset_sensei = 0;
1087     FLOPPY_DPRINTF("Set interrupt status to 0x%02x\n", fdctrl->status0);
1088 }
1089 
1090 /* Reset controller */
1091 void fdctrl_reset(FDCtrl *fdctrl, int do_irq)
1092 {
1093     int i;
1094 
1095     FLOPPY_DPRINTF("reset controller\n");
1096     fdctrl_reset_irq(fdctrl);
1097     /* Initialise controller */
1098     fdctrl->sra = 0;
1099     fdctrl->srb = 0xc0;
1100     if (!fdctrl->drives[1].blk) {
1101         fdctrl->sra |= FD_SRA_nDRV2;
1102     }
1103     fdctrl->cur_drv = 0;
1104     fdctrl->dor = FD_DOR_nRESET;
1105     fdctrl->dor |= (fdctrl->dma_chann != -1) ? FD_DOR_DMAEN : 0;
1106     fdctrl->msr = FD_MSR_RQM;
1107     fdctrl->reset_sensei = 0;
1108     timer_del(fdctrl->result_timer);
1109     /* FIFO state */
1110     fdctrl->data_pos = 0;
1111     fdctrl->data_len = 0;
1112     fdctrl->data_state = 0;
1113     fdctrl->data_dir = FD_DIR_WRITE;
1114     for (i = 0; i < MAX_FD; i++)
1115         fd_recalibrate(&fdctrl->drives[i]);
1116     fdctrl_to_command_phase(fdctrl);
1117     if (do_irq) {
1118         fdctrl->status0 |= FD_SR0_RDYCHG;
1119         fdctrl_raise_irq(fdctrl);
1120         fdctrl->reset_sensei = FD_RESET_SENSEI_COUNT;
1121     }
1122 }
1123 
1124 static inline FDrive *drv0(FDCtrl *fdctrl)
1125 {
1126     return &fdctrl->drives[(fdctrl->tdr & FD_TDR_BOOTSEL) >> 2];
1127 }
1128 
1129 static inline FDrive *drv1(FDCtrl *fdctrl)
1130 {
1131     if ((fdctrl->tdr & FD_TDR_BOOTSEL) < (1 << 2))
1132         return &fdctrl->drives[1];
1133     else
1134         return &fdctrl->drives[0];
1135 }
1136 
1137 #if MAX_FD == 4
1138 static inline FDrive *drv2(FDCtrl *fdctrl)
1139 {
1140     if ((fdctrl->tdr & FD_TDR_BOOTSEL) < (2 << 2))
1141         return &fdctrl->drives[2];
1142     else
1143         return &fdctrl->drives[1];
1144 }
1145 
1146 static inline FDrive *drv3(FDCtrl *fdctrl)
1147 {
1148     if ((fdctrl->tdr & FD_TDR_BOOTSEL) < (3 << 2))
1149         return &fdctrl->drives[3];
1150     else
1151         return &fdctrl->drives[2];
1152 }
1153 #endif
1154 
1155 static FDrive *get_drv(FDCtrl *fdctrl, int unit)
1156 {
1157     switch (unit) {
1158         case 0: return drv0(fdctrl);
1159         case 1: return drv1(fdctrl);
1160 #if MAX_FD == 4
1161         case 2: return drv2(fdctrl);
1162         case 3: return drv3(fdctrl);
1163 #endif
1164         default: return NULL;
1165     }
1166 }
1167 
1168 static FDrive *get_cur_drv(FDCtrl *fdctrl)
1169 {
1170     FDrive *cur_drv = get_drv(fdctrl, fdctrl->cur_drv);
1171 
1172     if (!cur_drv->blk) {
1173         /*
1174          * Kludge: empty drive line selected. Create an anonymous
1175          * BlockBackend to avoid NULL deref with various BlockBackend
1176          * API calls within this model (CVE-2021-20196).
1177          * Due to the controller QOM model limitations, we don't
1178          * attach the created to the controller device.
1179          */
1180         cur_drv->blk = blk_create_empty_drive();
1181     }
1182     return cur_drv;
1183 }
1184 
1185 /* Status A register : 0x00 (read-only) */
1186 static uint32_t fdctrl_read_statusA(FDCtrl *fdctrl)
1187 {
1188     uint32_t retval = fdctrl->sra;
1189 
1190     FLOPPY_DPRINTF("status register A: 0x%02x\n", retval);
1191 
1192     return retval;
1193 }
1194 
1195 /* Status B register : 0x01 (read-only) */
1196 static uint32_t fdctrl_read_statusB(FDCtrl *fdctrl)
1197 {
1198     uint32_t retval = fdctrl->srb;
1199 
1200     FLOPPY_DPRINTF("status register B: 0x%02x\n", retval);
1201 
1202     return retval;
1203 }
1204 
1205 /* Digital output register : 0x02 */
1206 static uint32_t fdctrl_read_dor(FDCtrl *fdctrl)
1207 {
1208     uint32_t retval = fdctrl->dor;
1209 
1210     /* Selected drive */
1211     retval |= fdctrl->cur_drv;
1212     FLOPPY_DPRINTF("digital output register: 0x%02x\n", retval);
1213 
1214     return retval;
1215 }
1216 
1217 static void fdctrl_write_dor(FDCtrl *fdctrl, uint32_t value)
1218 {
1219     FLOPPY_DPRINTF("digital output register set to 0x%02x\n", value);
1220 
1221     /* Motors */
1222     if (value & FD_DOR_MOTEN0)
1223         fdctrl->srb |= FD_SRB_MTR0;
1224     else
1225         fdctrl->srb &= ~FD_SRB_MTR0;
1226     if (value & FD_DOR_MOTEN1)
1227         fdctrl->srb |= FD_SRB_MTR1;
1228     else
1229         fdctrl->srb &= ~FD_SRB_MTR1;
1230 
1231     /* Drive */
1232     if (value & 1)
1233         fdctrl->srb |= FD_SRB_DR0;
1234     else
1235         fdctrl->srb &= ~FD_SRB_DR0;
1236 
1237     /* Reset */
1238     if (!(value & FD_DOR_nRESET)) {
1239         if (fdctrl->dor & FD_DOR_nRESET) {
1240             FLOPPY_DPRINTF("controller enter RESET state\n");
1241         }
1242     } else {
1243         if (!(fdctrl->dor & FD_DOR_nRESET)) {
1244             FLOPPY_DPRINTF("controller out of RESET state\n");
1245             fdctrl_reset(fdctrl, 1);
1246             fdctrl->dsr &= ~FD_DSR_PWRDOWN;
1247         }
1248     }
1249     /* Selected drive */
1250     fdctrl->cur_drv = value & FD_DOR_SELMASK;
1251 
1252     fdctrl->dor = value;
1253 }
1254 
1255 /* Tape drive register : 0x03 */
1256 static uint32_t fdctrl_read_tape(FDCtrl *fdctrl)
1257 {
1258     uint32_t retval = fdctrl->tdr;
1259 
1260     FLOPPY_DPRINTF("tape drive register: 0x%02x\n", retval);
1261 
1262     return retval;
1263 }
1264 
1265 static void fdctrl_write_tape(FDCtrl *fdctrl, uint32_t value)
1266 {
1267     /* Reset mode */
1268     if (!(fdctrl->dor & FD_DOR_nRESET)) {
1269         FLOPPY_DPRINTF("Floppy controller in RESET state !\n");
1270         return;
1271     }
1272     FLOPPY_DPRINTF("tape drive register set to 0x%02x\n", value);
1273     /* Disk boot selection indicator */
1274     fdctrl->tdr = value & FD_TDR_BOOTSEL;
1275     /* Tape indicators: never allow */
1276 }
1277 
1278 /* Main status register : 0x04 (read) */
1279 static uint32_t fdctrl_read_main_status(FDCtrl *fdctrl)
1280 {
1281     uint32_t retval = fdctrl->msr;
1282 
1283     fdctrl->dsr &= ~FD_DSR_PWRDOWN;
1284     fdctrl->dor |= FD_DOR_nRESET;
1285 
1286     FLOPPY_DPRINTF("main status register: 0x%02x\n", retval);
1287 
1288     return retval;
1289 }
1290 
1291 /* Data select rate register : 0x04 (write) */
1292 static void fdctrl_write_rate(FDCtrl *fdctrl, uint32_t value)
1293 {
1294     /* Reset mode */
1295     if (!(fdctrl->dor & FD_DOR_nRESET)) {
1296         FLOPPY_DPRINTF("Floppy controller in RESET state !\n");
1297         return;
1298     }
1299     FLOPPY_DPRINTF("select rate register set to 0x%02x\n", value);
1300     /* Reset: autoclear */
1301     if (value & FD_DSR_SWRESET) {
1302         fdctrl->dor &= ~FD_DOR_nRESET;
1303         fdctrl_reset(fdctrl, 1);
1304         fdctrl->dor |= FD_DOR_nRESET;
1305     }
1306     if (value & FD_DSR_PWRDOWN) {
1307         fdctrl_reset(fdctrl, 1);
1308     }
1309     fdctrl->dsr = value;
1310 }
1311 
1312 /* Configuration control register: 0x07 (write) */
1313 static void fdctrl_write_ccr(FDCtrl *fdctrl, uint32_t value)
1314 {
1315     /* Reset mode */
1316     if (!(fdctrl->dor & FD_DOR_nRESET)) {
1317         FLOPPY_DPRINTF("Floppy controller in RESET state !\n");
1318         return;
1319     }
1320     FLOPPY_DPRINTF("configuration control register set to 0x%02x\n", value);
1321 
1322     /* Only the rate selection bits used in AT mode, and we
1323      * store those in the DSR.
1324      */
1325     fdctrl->dsr = (fdctrl->dsr & ~FD_DSR_DRATEMASK) |
1326                   (value & FD_DSR_DRATEMASK);
1327 }
1328 
1329 static int fdctrl_media_changed(FDrive *drv)
1330 {
1331     return drv->media_changed;
1332 }
1333 
1334 /* Digital input register : 0x07 (read-only) */
1335 static uint32_t fdctrl_read_dir(FDCtrl *fdctrl)
1336 {
1337     uint32_t retval = 0;
1338 
1339     if (fdctrl_media_changed(get_cur_drv(fdctrl))) {
1340         retval |= FD_DIR_DSKCHG;
1341     }
1342     if (retval != 0) {
1343         FLOPPY_DPRINTF("Floppy digital input register: 0x%02x\n", retval);
1344     }
1345 
1346     return retval;
1347 }
1348 
1349 /* Clear the FIFO and update the state for receiving the next command */
1350 static void fdctrl_to_command_phase(FDCtrl *fdctrl)
1351 {
1352     fdctrl->phase = FD_PHASE_COMMAND;
1353     fdctrl->data_dir = FD_DIR_WRITE;
1354     fdctrl->data_pos = 0;
1355     fdctrl->data_len = 1; /* Accept command byte, adjust for params later */
1356     fdctrl->msr &= ~(FD_MSR_CMDBUSY | FD_MSR_DIO);
1357     fdctrl->msr |= FD_MSR_RQM;
1358 }
1359 
1360 /* Update the state to allow the guest to read out the command status.
1361  * @fifo_len is the number of result bytes to be read out. */
1362 static void fdctrl_to_result_phase(FDCtrl *fdctrl, int fifo_len)
1363 {
1364     fdctrl->phase = FD_PHASE_RESULT;
1365     fdctrl->data_dir = FD_DIR_READ;
1366     fdctrl->data_len = fifo_len;
1367     fdctrl->data_pos = 0;
1368     fdctrl->msr |= FD_MSR_CMDBUSY | FD_MSR_RQM | FD_MSR_DIO;
1369 }
1370 
1371 /* Set an error: unimplemented/unknown command */
1372 static void fdctrl_unimplemented(FDCtrl *fdctrl, int direction)
1373 {
1374     qemu_log_mask(LOG_UNIMP, "fdc: unimplemented command 0x%02x\n",
1375                   fdctrl->fifo[0]);
1376     fdctrl->fifo[0] = FD_SR0_INVCMD;
1377     fdctrl_to_result_phase(fdctrl, 1);
1378 }
1379 
1380 /* Seek to next sector
1381  * returns 0 when end of track reached (for DBL_SIDES on head 1)
1382  * otherwise returns 1
1383  */
1384 static int fdctrl_seek_to_next_sect(FDCtrl *fdctrl, FDrive *cur_drv)
1385 {
1386     FLOPPY_DPRINTF("seek to next sector (%d %02x %02x => %d)\n",
1387                    cur_drv->head, cur_drv->track, cur_drv->sect,
1388                    fd_sector(cur_drv));
1389     /* XXX: cur_drv->sect >= cur_drv->last_sect should be an
1390        error in fact */
1391     uint8_t new_head = cur_drv->head;
1392     uint8_t new_track = cur_drv->track;
1393     uint8_t new_sect = cur_drv->sect;
1394 
1395     int ret = 1;
1396 
1397     if (new_sect >= cur_drv->last_sect ||
1398         new_sect == fdctrl->eot) {
1399         new_sect = 1;
1400         if (FD_MULTI_TRACK(fdctrl->data_state)) {
1401             if (new_head == 0 &&
1402                 (cur_drv->flags & FDISK_DBL_SIDES) != 0) {
1403                 new_head = 1;
1404             } else {
1405                 new_head = 0;
1406                 new_track++;
1407                 fdctrl->status0 |= FD_SR0_SEEK;
1408                 if ((cur_drv->flags & FDISK_DBL_SIDES) == 0) {
1409                     ret = 0;
1410                 }
1411             }
1412         } else {
1413             fdctrl->status0 |= FD_SR0_SEEK;
1414             new_track++;
1415             ret = 0;
1416         }
1417         if (ret == 1) {
1418             FLOPPY_DPRINTF("seek to next track (%d %02x %02x => %d)\n",
1419                     new_head, new_track, new_sect, fd_sector(cur_drv));
1420         }
1421     } else {
1422         new_sect++;
1423     }
1424     fd_seek(cur_drv, new_head, new_track, new_sect, 1);
1425     return ret;
1426 }
1427 
1428 /* Callback for transfer end (stop or abort) */
1429 static void fdctrl_stop_transfer(FDCtrl *fdctrl, uint8_t status0,
1430                                  uint8_t status1, uint8_t status2)
1431 {
1432     FDrive *cur_drv;
1433     cur_drv = get_cur_drv(fdctrl);
1434 
1435     fdctrl->status0 &= ~(FD_SR0_DS0 | FD_SR0_DS1 | FD_SR0_HEAD);
1436     fdctrl->status0 |= GET_CUR_DRV(fdctrl);
1437     if (cur_drv->head) {
1438         fdctrl->status0 |= FD_SR0_HEAD;
1439     }
1440     fdctrl->status0 |= status0;
1441 
1442     FLOPPY_DPRINTF("transfer status: %02x %02x %02x (%02x)\n",
1443                    status0, status1, status2, fdctrl->status0);
1444     fdctrl->fifo[0] = fdctrl->status0;
1445     fdctrl->fifo[1] = status1;
1446     fdctrl->fifo[2] = status2;
1447     fdctrl->fifo[3] = cur_drv->track;
1448     fdctrl->fifo[4] = cur_drv->head;
1449     fdctrl->fifo[5] = cur_drv->sect;
1450     fdctrl->fifo[6] = FD_SECTOR_SC;
1451     fdctrl->data_dir = FD_DIR_READ;
1452     if (fdctrl->dma_chann != -1 && !(fdctrl->msr & FD_MSR_NONDMA)) {
1453         IsaDmaClass *k = ISADMA_GET_CLASS(fdctrl->dma);
1454         k->release_DREQ(fdctrl->dma, fdctrl->dma_chann);
1455     }
1456     fdctrl->msr |= FD_MSR_RQM | FD_MSR_DIO;
1457     fdctrl->msr &= ~FD_MSR_NONDMA;
1458 
1459     fdctrl_to_result_phase(fdctrl, 7);
1460     fdctrl_raise_irq(fdctrl);
1461 }
1462 
1463 /* Prepare a data transfer (either DMA or FIFO) */
1464 static void fdctrl_start_transfer(FDCtrl *fdctrl, int direction)
1465 {
1466     FDrive *cur_drv;
1467     uint8_t kh, kt, ks;
1468 
1469     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1470     cur_drv = get_cur_drv(fdctrl);
1471     kt = fdctrl->fifo[2];
1472     kh = fdctrl->fifo[3];
1473     ks = fdctrl->fifo[4];
1474     FLOPPY_DPRINTF("Start transfer at %d %d %02x %02x (%d)\n",
1475                    GET_CUR_DRV(fdctrl), kh, kt, ks,
1476                    fd_sector_calc(kh, kt, ks, cur_drv->last_sect,
1477                                   NUM_SIDES(cur_drv)));
1478     switch (fd_seek(cur_drv, kh, kt, ks, fdctrl->config & FD_CONFIG_EIS)) {
1479     case 2:
1480         /* sect too big */
1481         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1482         fdctrl->fifo[3] = kt;
1483         fdctrl->fifo[4] = kh;
1484         fdctrl->fifo[5] = ks;
1485         return;
1486     case 3:
1487         /* track too big */
1488         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_EC, 0x00);
1489         fdctrl->fifo[3] = kt;
1490         fdctrl->fifo[4] = kh;
1491         fdctrl->fifo[5] = ks;
1492         return;
1493     case 4:
1494         /* No seek enabled */
1495         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1496         fdctrl->fifo[3] = kt;
1497         fdctrl->fifo[4] = kh;
1498         fdctrl->fifo[5] = ks;
1499         return;
1500     case 1:
1501         fdctrl->status0 |= FD_SR0_SEEK;
1502         break;
1503     default:
1504         break;
1505     }
1506 
1507     /* Check the data rate. If the programmed data rate does not match
1508      * the currently inserted medium, the operation has to fail. */
1509     if ((fdctrl->dsr & FD_DSR_DRATEMASK) != cur_drv->media_rate) {
1510         FLOPPY_DPRINTF("data rate mismatch (fdc=%d, media=%d)\n",
1511                        fdctrl->dsr & FD_DSR_DRATEMASK, cur_drv->media_rate);
1512         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_MA, 0x00);
1513         fdctrl->fifo[3] = kt;
1514         fdctrl->fifo[4] = kh;
1515         fdctrl->fifo[5] = ks;
1516         return;
1517     }
1518 
1519     /* Set the FIFO state */
1520     fdctrl->data_dir = direction;
1521     fdctrl->data_pos = 0;
1522     assert(fdctrl->msr & FD_MSR_CMDBUSY);
1523     if (fdctrl->fifo[0] & 0x80)
1524         fdctrl->data_state |= FD_STATE_MULTI;
1525     else
1526         fdctrl->data_state &= ~FD_STATE_MULTI;
1527     if (fdctrl->fifo[5] == 0) {
1528         fdctrl->data_len = fdctrl->fifo[8];
1529     } else {
1530         int tmp;
1531         fdctrl->data_len = 128 << (fdctrl->fifo[5] > 7 ? 7 : fdctrl->fifo[5]);
1532         tmp = (fdctrl->fifo[6] - ks + 1);
1533         if (tmp < 0) {
1534             FLOPPY_DPRINTF("invalid EOT: %d\n", tmp);
1535             fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_MA, 0x00);
1536             fdctrl->fifo[3] = kt;
1537             fdctrl->fifo[4] = kh;
1538             fdctrl->fifo[5] = ks;
1539             return;
1540         }
1541         if (fdctrl->fifo[0] & 0x80)
1542             tmp += fdctrl->fifo[6];
1543         fdctrl->data_len *= tmp;
1544     }
1545     fdctrl->eot = fdctrl->fifo[6];
1546     if (fdctrl->dor & FD_DOR_DMAEN) {
1547         /* DMA transfer is enabled. */
1548         IsaDmaClass *k = ISADMA_GET_CLASS(fdctrl->dma);
1549 
1550         FLOPPY_DPRINTF("direction=%d (%d - %d)\n",
1551                        direction, (128 << fdctrl->fifo[5]) *
1552                        (cur_drv->last_sect - ks + 1), fdctrl->data_len);
1553 
1554         /* No access is allowed until DMA transfer has completed */
1555         fdctrl->msr &= ~FD_MSR_RQM;
1556         if (direction != FD_DIR_VERIFY) {
1557             /*
1558              * Now, we just have to wait for the DMA controller to
1559              * recall us...
1560              */
1561             k->hold_DREQ(fdctrl->dma, fdctrl->dma_chann);
1562             k->schedule(fdctrl->dma);
1563         } else {
1564             /* Start transfer */
1565             fdctrl_transfer_handler(fdctrl, fdctrl->dma_chann, 0,
1566                     fdctrl->data_len);
1567         }
1568         return;
1569     }
1570     FLOPPY_DPRINTF("start non-DMA transfer\n");
1571     fdctrl->msr |= FD_MSR_NONDMA | FD_MSR_RQM;
1572     if (direction != FD_DIR_WRITE)
1573         fdctrl->msr |= FD_MSR_DIO;
1574     /* IO based transfer: calculate len */
1575     fdctrl_raise_irq(fdctrl);
1576 }
1577 
1578 /* Prepare a transfer of deleted data */
1579 static void fdctrl_start_transfer_del(FDCtrl *fdctrl, int direction)
1580 {
1581     qemu_log_mask(LOG_UNIMP, "fdctrl_start_transfer_del() unimplemented\n");
1582 
1583     /* We don't handle deleted data,
1584      * so we don't return *ANYTHING*
1585      */
1586     fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
1587 }
1588 
1589 /* handlers for DMA transfers */
1590 int fdctrl_transfer_handler(void *opaque, int nchan, int dma_pos, int dma_len)
1591 {
1592     FDCtrl *fdctrl;
1593     FDrive *cur_drv;
1594     int len, start_pos, rel_pos;
1595     uint8_t status0 = 0x00, status1 = 0x00, status2 = 0x00;
1596     IsaDmaClass *k;
1597 
1598     fdctrl = opaque;
1599     if (fdctrl->msr & FD_MSR_RQM) {
1600         FLOPPY_DPRINTF("Not in DMA transfer mode !\n");
1601         return 0;
1602     }
1603     k = ISADMA_GET_CLASS(fdctrl->dma);
1604     cur_drv = get_cur_drv(fdctrl);
1605     if (fdctrl->data_dir == FD_DIR_SCANE || fdctrl->data_dir == FD_DIR_SCANL ||
1606         fdctrl->data_dir == FD_DIR_SCANH)
1607         status2 = FD_SR2_SNS;
1608     if (dma_len > fdctrl->data_len)
1609         dma_len = fdctrl->data_len;
1610     if (cur_drv->blk == NULL) {
1611         if (fdctrl->data_dir == FD_DIR_WRITE)
1612             fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
1613         else
1614             fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1615         len = 0;
1616         goto transfer_error;
1617     }
1618     rel_pos = fdctrl->data_pos % FD_SECTOR_LEN;
1619     for (start_pos = fdctrl->data_pos; fdctrl->data_pos < dma_len;) {
1620         len = dma_len - fdctrl->data_pos;
1621         if (len + rel_pos > FD_SECTOR_LEN)
1622             len = FD_SECTOR_LEN - rel_pos;
1623         FLOPPY_DPRINTF("copy %d bytes (%d %d %d) %d pos %d %02x "
1624                        "(%d-0x%08x 0x%08x)\n", len, dma_len, fdctrl->data_pos,
1625                        fdctrl->data_len, GET_CUR_DRV(fdctrl), cur_drv->head,
1626                        cur_drv->track, cur_drv->sect, fd_sector(cur_drv),
1627                        fd_sector(cur_drv) * FD_SECTOR_LEN);
1628         if (fdctrl->data_dir != FD_DIR_WRITE ||
1629             len < FD_SECTOR_LEN || rel_pos != 0) {
1630             /* READ & SCAN commands and realign to a sector for WRITE */
1631             if (blk_pread(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
1632                           fdctrl->fifo, 0) < 0) {
1633                 FLOPPY_DPRINTF("Floppy: error getting sector %d\n",
1634                                fd_sector(cur_drv));
1635                 /* Sure, image size is too small... */
1636                 memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
1637             }
1638         }
1639         switch (fdctrl->data_dir) {
1640         case FD_DIR_READ:
1641             /* READ commands */
1642             k->write_memory(fdctrl->dma, nchan, fdctrl->fifo + rel_pos,
1643                             fdctrl->data_pos, len);
1644             break;
1645         case FD_DIR_WRITE:
1646             /* WRITE commands */
1647             if (cur_drv->ro) {
1648                 /* Handle readonly medium early, no need to do DMA, touch the
1649                  * LED or attempt any writes. A real floppy doesn't attempt
1650                  * to write to readonly media either. */
1651                 fdctrl_stop_transfer(fdctrl,
1652                                      FD_SR0_ABNTERM | FD_SR0_SEEK, FD_SR1_NW,
1653                                      0x00);
1654                 goto transfer_error;
1655             }
1656 
1657             k->read_memory(fdctrl->dma, nchan, fdctrl->fifo + rel_pos,
1658                            fdctrl->data_pos, len);
1659             if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
1660                            fdctrl->fifo, 0) < 0) {
1661                 FLOPPY_DPRINTF("error writing sector %d\n",
1662                                fd_sector(cur_drv));
1663                 fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
1664                 goto transfer_error;
1665             }
1666             break;
1667         case FD_DIR_VERIFY:
1668             /* VERIFY commands */
1669             break;
1670         default:
1671             /* SCAN commands */
1672             {
1673                 uint8_t tmpbuf[FD_SECTOR_LEN];
1674                 int ret;
1675                 k->read_memory(fdctrl->dma, nchan, tmpbuf, fdctrl->data_pos,
1676                                len);
1677                 ret = memcmp(tmpbuf, fdctrl->fifo + rel_pos, len);
1678                 if (ret == 0) {
1679                     status2 = FD_SR2_SEH;
1680                     goto end_transfer;
1681                 }
1682                 if ((ret < 0 && fdctrl->data_dir == FD_DIR_SCANL) ||
1683                     (ret > 0 && fdctrl->data_dir == FD_DIR_SCANH)) {
1684                     status2 = 0x00;
1685                     goto end_transfer;
1686                 }
1687             }
1688             break;
1689         }
1690         fdctrl->data_pos += len;
1691         rel_pos = fdctrl->data_pos % FD_SECTOR_LEN;
1692         if (rel_pos == 0) {
1693             /* Seek to next sector */
1694             if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv))
1695                 break;
1696         }
1697     }
1698  end_transfer:
1699     len = fdctrl->data_pos - start_pos;
1700     FLOPPY_DPRINTF("end transfer %d %d %d\n",
1701                    fdctrl->data_pos, len, fdctrl->data_len);
1702     if (fdctrl->data_dir == FD_DIR_SCANE ||
1703         fdctrl->data_dir == FD_DIR_SCANL ||
1704         fdctrl->data_dir == FD_DIR_SCANH)
1705         status2 = FD_SR2_SEH;
1706     fdctrl->data_len -= len;
1707     fdctrl_stop_transfer(fdctrl, status0, status1, status2);
1708  transfer_error:
1709 
1710     return len;
1711 }
1712 
1713 /* Data register : 0x05 */
1714 static uint32_t fdctrl_read_data(FDCtrl *fdctrl)
1715 {
1716     FDrive *cur_drv;
1717     uint32_t retval = 0;
1718     uint32_t pos;
1719 
1720     cur_drv = get_cur_drv(fdctrl);
1721     fdctrl->dsr &= ~FD_DSR_PWRDOWN;
1722     if (!(fdctrl->msr & FD_MSR_RQM) || !(fdctrl->msr & FD_MSR_DIO)) {
1723         FLOPPY_DPRINTF("error: controller not ready for reading\n");
1724         return 0;
1725     }
1726 
1727     /* If data_len spans multiple sectors, the current position in the FIFO
1728      * wraps around while fdctrl->data_pos is the real position in the whole
1729      * request. */
1730     pos = fdctrl->data_pos;
1731     pos %= FD_SECTOR_LEN;
1732 
1733     switch (fdctrl->phase) {
1734     case FD_PHASE_EXECUTION:
1735         assert(fdctrl->msr & FD_MSR_NONDMA);
1736         if (pos == 0) {
1737             if (fdctrl->data_pos != 0)
1738                 if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv)) {
1739                     FLOPPY_DPRINTF("error seeking to next sector %d\n",
1740                                    fd_sector(cur_drv));
1741                     return 0;
1742                 }
1743             if (blk_pread(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
1744                           fdctrl->fifo, 0)
1745                 < 0) {
1746                 FLOPPY_DPRINTF("error getting sector %d\n",
1747                                fd_sector(cur_drv));
1748                 /* Sure, image size is too small... */
1749                 memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
1750             }
1751         }
1752 
1753         if (++fdctrl->data_pos == fdctrl->data_len) {
1754             fdctrl->msr &= ~FD_MSR_RQM;
1755             fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
1756         }
1757         break;
1758 
1759     case FD_PHASE_RESULT:
1760         assert(!(fdctrl->msr & FD_MSR_NONDMA));
1761         if (++fdctrl->data_pos == fdctrl->data_len) {
1762             fdctrl->msr &= ~FD_MSR_RQM;
1763             fdctrl_to_command_phase(fdctrl);
1764             fdctrl_reset_irq(fdctrl);
1765         }
1766         break;
1767 
1768     case FD_PHASE_COMMAND:
1769     default:
1770         abort();
1771     }
1772 
1773     retval = fdctrl->fifo[pos];
1774     FLOPPY_DPRINTF("data register: 0x%02x\n", retval);
1775 
1776     return retval;
1777 }
1778 
1779 static void fdctrl_format_sector(FDCtrl *fdctrl)
1780 {
1781     FDrive *cur_drv;
1782     uint8_t kh, kt, ks;
1783 
1784     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1785     cur_drv = get_cur_drv(fdctrl);
1786     kt = fdctrl->fifo[6];
1787     kh = fdctrl->fifo[7];
1788     ks = fdctrl->fifo[8];
1789     FLOPPY_DPRINTF("format sector at %d %d %02x %02x (%d)\n",
1790                    GET_CUR_DRV(fdctrl), kh, kt, ks,
1791                    fd_sector_calc(kh, kt, ks, cur_drv->last_sect,
1792                                   NUM_SIDES(cur_drv)));
1793     switch (fd_seek(cur_drv, kh, kt, ks, fdctrl->config & FD_CONFIG_EIS)) {
1794     case 2:
1795         /* sect too big */
1796         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1797         fdctrl->fifo[3] = kt;
1798         fdctrl->fifo[4] = kh;
1799         fdctrl->fifo[5] = ks;
1800         return;
1801     case 3:
1802         /* track too big */
1803         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_EC, 0x00);
1804         fdctrl->fifo[3] = kt;
1805         fdctrl->fifo[4] = kh;
1806         fdctrl->fifo[5] = ks;
1807         return;
1808     case 4:
1809         /* No seek enabled */
1810         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, 0x00, 0x00);
1811         fdctrl->fifo[3] = kt;
1812         fdctrl->fifo[4] = kh;
1813         fdctrl->fifo[5] = ks;
1814         return;
1815     case 1:
1816         fdctrl->status0 |= FD_SR0_SEEK;
1817         break;
1818     default:
1819         break;
1820     }
1821     memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
1822     if (cur_drv->blk == NULL ||
1823         blk_pwrite(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
1824                    fdctrl->fifo, 0) < 0) {
1825         FLOPPY_DPRINTF("error formatting sector %d\n", fd_sector(cur_drv));
1826         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM | FD_SR0_SEEK, 0x00, 0x00);
1827     } else {
1828         if (cur_drv->sect == cur_drv->last_sect) {
1829             fdctrl->data_state &= ~FD_STATE_FORMAT;
1830             /* Last sector done */
1831             fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
1832         } else {
1833             /* More to do */
1834             fdctrl->data_pos = 0;
1835             fdctrl->data_len = 4;
1836         }
1837     }
1838 }
1839 
1840 static void fdctrl_handle_lock(FDCtrl *fdctrl, int direction)
1841 {
1842     fdctrl->lock = (fdctrl->fifo[0] & 0x80) ? 1 : 0;
1843     fdctrl->fifo[0] = fdctrl->lock << 4;
1844     fdctrl_to_result_phase(fdctrl, 1);
1845 }
1846 
1847 static void fdctrl_handle_dumpreg(FDCtrl *fdctrl, int direction)
1848 {
1849     FDrive *cur_drv = get_cur_drv(fdctrl);
1850 
1851     /* Drives position */
1852     fdctrl->fifo[0] = drv0(fdctrl)->track;
1853     fdctrl->fifo[1] = drv1(fdctrl)->track;
1854 #if MAX_FD == 4
1855     fdctrl->fifo[2] = drv2(fdctrl)->track;
1856     fdctrl->fifo[3] = drv3(fdctrl)->track;
1857 #else
1858     fdctrl->fifo[2] = 0;
1859     fdctrl->fifo[3] = 0;
1860 #endif
1861     /* timers */
1862     fdctrl->fifo[4] = fdctrl->timer0;
1863     fdctrl->fifo[5] = (fdctrl->timer1 << 1) | (fdctrl->dor & FD_DOR_DMAEN ? 1 : 0);
1864     fdctrl->fifo[6] = cur_drv->last_sect;
1865     fdctrl->fifo[7] = (fdctrl->lock << 7) |
1866         (cur_drv->perpendicular << 2);
1867     fdctrl->fifo[8] = fdctrl->config;
1868     fdctrl->fifo[9] = fdctrl->precomp_trk;
1869     fdctrl_to_result_phase(fdctrl, 10);
1870 }
1871 
1872 static void fdctrl_handle_version(FDCtrl *fdctrl, int direction)
1873 {
1874     /* Controller's version */
1875     fdctrl->fifo[0] = fdctrl->version;
1876     fdctrl_to_result_phase(fdctrl, 1);
1877 }
1878 
1879 static void fdctrl_handle_partid(FDCtrl *fdctrl, int direction)
1880 {
1881     fdctrl->fifo[0] = 0x41; /* Stepping 1 */
1882     fdctrl_to_result_phase(fdctrl, 1);
1883 }
1884 
1885 static void fdctrl_handle_restore(FDCtrl *fdctrl, int direction)
1886 {
1887     FDrive *cur_drv = get_cur_drv(fdctrl);
1888 
1889     /* Drives position */
1890     drv0(fdctrl)->track = fdctrl->fifo[3];
1891     drv1(fdctrl)->track = fdctrl->fifo[4];
1892 #if MAX_FD == 4
1893     drv2(fdctrl)->track = fdctrl->fifo[5];
1894     drv3(fdctrl)->track = fdctrl->fifo[6];
1895 #endif
1896     /* timers */
1897     fdctrl->timer0 = fdctrl->fifo[7];
1898     fdctrl->timer1 = fdctrl->fifo[8];
1899     cur_drv->last_sect = fdctrl->fifo[9];
1900     fdctrl->lock = fdctrl->fifo[10] >> 7;
1901     cur_drv->perpendicular = (fdctrl->fifo[10] >> 2) & 0xF;
1902     fdctrl->config = fdctrl->fifo[11];
1903     fdctrl->precomp_trk = fdctrl->fifo[12];
1904     fdctrl->pwrd = fdctrl->fifo[13];
1905     fdctrl_to_command_phase(fdctrl);
1906 }
1907 
1908 static void fdctrl_handle_save(FDCtrl *fdctrl, int direction)
1909 {
1910     FDrive *cur_drv = get_cur_drv(fdctrl);
1911 
1912     fdctrl->fifo[0] = 0;
1913     fdctrl->fifo[1] = 0;
1914     /* Drives position */
1915     fdctrl->fifo[2] = drv0(fdctrl)->track;
1916     fdctrl->fifo[3] = drv1(fdctrl)->track;
1917 #if MAX_FD == 4
1918     fdctrl->fifo[4] = drv2(fdctrl)->track;
1919     fdctrl->fifo[5] = drv3(fdctrl)->track;
1920 #else
1921     fdctrl->fifo[4] = 0;
1922     fdctrl->fifo[5] = 0;
1923 #endif
1924     /* timers */
1925     fdctrl->fifo[6] = fdctrl->timer0;
1926     fdctrl->fifo[7] = fdctrl->timer1;
1927     fdctrl->fifo[8] = cur_drv->last_sect;
1928     fdctrl->fifo[9] = (fdctrl->lock << 7) |
1929         (cur_drv->perpendicular << 2);
1930     fdctrl->fifo[10] = fdctrl->config;
1931     fdctrl->fifo[11] = fdctrl->precomp_trk;
1932     fdctrl->fifo[12] = fdctrl->pwrd;
1933     fdctrl->fifo[13] = 0;
1934     fdctrl->fifo[14] = 0;
1935     fdctrl_to_result_phase(fdctrl, 15);
1936 }
1937 
1938 static void fdctrl_handle_readid(FDCtrl *fdctrl, int direction)
1939 {
1940     FDrive *cur_drv = get_cur_drv(fdctrl);
1941 
1942     cur_drv->head = (fdctrl->fifo[1] >> 2) & 1;
1943     timer_mod(fdctrl->result_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
1944              (NANOSECONDS_PER_SECOND / 50));
1945 }
1946 
1947 static void fdctrl_handle_format_track(FDCtrl *fdctrl, int direction)
1948 {
1949     FDrive *cur_drv;
1950 
1951     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1952     cur_drv = get_cur_drv(fdctrl);
1953     fdctrl->data_state |= FD_STATE_FORMAT;
1954     if (fdctrl->fifo[0] & 0x80)
1955         fdctrl->data_state |= FD_STATE_MULTI;
1956     else
1957         fdctrl->data_state &= ~FD_STATE_MULTI;
1958     cur_drv->bps =
1959         fdctrl->fifo[2] > 7 ? 16384 : 128 << fdctrl->fifo[2];
1960 #if 0
1961     cur_drv->last_sect =
1962         cur_drv->flags & FDISK_DBL_SIDES ? fdctrl->fifo[3] :
1963         fdctrl->fifo[3] / 2;
1964 #else
1965     cur_drv->last_sect = fdctrl->fifo[3];
1966 #endif
1967     /* TODO: implement format using DMA expected by the Bochs BIOS
1968      * and Linux fdformat (read 3 bytes per sector via DMA and fill
1969      * the sector with the specified fill byte
1970      */
1971     fdctrl->data_state &= ~FD_STATE_FORMAT;
1972     fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
1973 }
1974 
1975 static void fdctrl_handle_specify(FDCtrl *fdctrl, int direction)
1976 {
1977     fdctrl->timer0 = (fdctrl->fifo[1] >> 4) & 0xF;
1978     fdctrl->timer1 = fdctrl->fifo[2] >> 1;
1979     if (fdctrl->fifo[2] & 1)
1980         fdctrl->dor &= ~FD_DOR_DMAEN;
1981     else
1982         fdctrl->dor |= FD_DOR_DMAEN;
1983     /* No result back */
1984     fdctrl_to_command_phase(fdctrl);
1985 }
1986 
1987 static void fdctrl_handle_sense_drive_status(FDCtrl *fdctrl, int direction)
1988 {
1989     FDrive *cur_drv;
1990 
1991     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
1992     cur_drv = get_cur_drv(fdctrl);
1993     cur_drv->head = (fdctrl->fifo[1] >> 2) & 1;
1994     /* 1 Byte status back */
1995     fdctrl->fifo[0] = (cur_drv->ro << 6) |
1996         (cur_drv->track == 0 ? 0x10 : 0x00) |
1997         (cur_drv->head << 2) |
1998         GET_CUR_DRV(fdctrl) |
1999         0x28;
2000     fdctrl_to_result_phase(fdctrl, 1);
2001 }
2002 
2003 static void fdctrl_handle_recalibrate(FDCtrl *fdctrl, int direction)
2004 {
2005     FDrive *cur_drv;
2006 
2007     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
2008     cur_drv = get_cur_drv(fdctrl);
2009     fd_recalibrate(cur_drv);
2010     fdctrl_to_command_phase(fdctrl);
2011     /* Raise Interrupt */
2012     fdctrl->status0 |= FD_SR0_SEEK;
2013     fdctrl_raise_irq(fdctrl);
2014 }
2015 
2016 static void fdctrl_handle_sense_interrupt_status(FDCtrl *fdctrl, int direction)
2017 {
2018     FDrive *cur_drv = get_cur_drv(fdctrl);
2019 
2020     if (fdctrl->reset_sensei > 0) {
2021         fdctrl->fifo[0] =
2022             FD_SR0_RDYCHG + FD_RESET_SENSEI_COUNT - fdctrl->reset_sensei;
2023         fdctrl->reset_sensei--;
2024     } else if (!(fdctrl->sra & FD_SRA_INTPEND)) {
2025         fdctrl->fifo[0] = FD_SR0_INVCMD;
2026         fdctrl_to_result_phase(fdctrl, 1);
2027         return;
2028     } else {
2029         fdctrl->fifo[0] =
2030                 (fdctrl->status0 & ~(FD_SR0_HEAD | FD_SR0_DS1 | FD_SR0_DS0))
2031                 | GET_CUR_DRV(fdctrl);
2032     }
2033 
2034     fdctrl->fifo[1] = cur_drv->track;
2035     fdctrl_to_result_phase(fdctrl, 2);
2036     fdctrl_reset_irq(fdctrl);
2037     fdctrl->status0 = FD_SR0_RDYCHG;
2038 }
2039 
2040 static void fdctrl_handle_seek(FDCtrl *fdctrl, int direction)
2041 {
2042     FDrive *cur_drv;
2043 
2044     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
2045     cur_drv = get_cur_drv(fdctrl);
2046     fdctrl_to_command_phase(fdctrl);
2047     /* The seek command just sends step pulses to the drive and doesn't care if
2048      * there is a medium inserted of if it's banging the head against the drive.
2049      */
2050     fd_seek(cur_drv, cur_drv->head, fdctrl->fifo[2], cur_drv->sect, 1);
2051     /* Raise Interrupt */
2052     fdctrl->status0 |= FD_SR0_SEEK;
2053     fdctrl_raise_irq(fdctrl);
2054 }
2055 
2056 static void fdctrl_handle_perpendicular_mode(FDCtrl *fdctrl, int direction)
2057 {
2058     FDrive *cur_drv = get_cur_drv(fdctrl);
2059 
2060     if (fdctrl->fifo[1] & 0x80)
2061         cur_drv->perpendicular = fdctrl->fifo[1] & 0x7;
2062     /* No result back */
2063     fdctrl_to_command_phase(fdctrl);
2064 }
2065 
2066 static void fdctrl_handle_configure(FDCtrl *fdctrl, int direction)
2067 {
2068     fdctrl->config = fdctrl->fifo[2];
2069     fdctrl->precomp_trk =  fdctrl->fifo[3];
2070     /* No result back */
2071     fdctrl_to_command_phase(fdctrl);
2072 }
2073 
2074 static void fdctrl_handle_powerdown_mode(FDCtrl *fdctrl, int direction)
2075 {
2076     fdctrl->pwrd = fdctrl->fifo[1];
2077     fdctrl->fifo[0] = fdctrl->fifo[1];
2078     fdctrl_to_result_phase(fdctrl, 1);
2079 }
2080 
2081 static void fdctrl_handle_option(FDCtrl *fdctrl, int direction)
2082 {
2083     /* No result back */
2084     fdctrl_to_command_phase(fdctrl);
2085 }
2086 
2087 static void fdctrl_handle_drive_specification_command(FDCtrl *fdctrl, int direction)
2088 {
2089     FDrive *cur_drv = get_cur_drv(fdctrl);
2090     uint32_t pos;
2091 
2092     pos = fdctrl->data_pos - 1;
2093     pos %= FD_SECTOR_LEN;
2094     if (fdctrl->fifo[pos] & 0x80) {
2095         /* Command parameters done */
2096         if (fdctrl->fifo[pos] & 0x40) {
2097             fdctrl->fifo[0] = fdctrl->fifo[1];
2098             fdctrl->fifo[2] = 0;
2099             fdctrl->fifo[3] = 0;
2100             fdctrl_to_result_phase(fdctrl, 4);
2101         } else {
2102             fdctrl_to_command_phase(fdctrl);
2103         }
2104     } else if (fdctrl->data_len > 7) {
2105         /* ERROR */
2106         fdctrl->fifo[0] = 0x80 |
2107             (cur_drv->head << 2) | GET_CUR_DRV(fdctrl);
2108         fdctrl_to_result_phase(fdctrl, 1);
2109     }
2110 }
2111 
2112 static void fdctrl_handle_relative_seek_in(FDCtrl *fdctrl, int direction)
2113 {
2114     FDrive *cur_drv;
2115 
2116     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
2117     cur_drv = get_cur_drv(fdctrl);
2118     if (fdctrl->fifo[2] + cur_drv->track >= cur_drv->max_track) {
2119         fd_seek(cur_drv, cur_drv->head, cur_drv->max_track - 1,
2120                 cur_drv->sect, 1);
2121     } else {
2122         fd_seek(cur_drv, cur_drv->head,
2123                 cur_drv->track + fdctrl->fifo[2], cur_drv->sect, 1);
2124     }
2125     fdctrl_to_command_phase(fdctrl);
2126     /* Raise Interrupt */
2127     fdctrl->status0 |= FD_SR0_SEEK;
2128     fdctrl_raise_irq(fdctrl);
2129 }
2130 
2131 static void fdctrl_handle_relative_seek_out(FDCtrl *fdctrl, int direction)
2132 {
2133     FDrive *cur_drv;
2134 
2135     SET_CUR_DRV(fdctrl, fdctrl->fifo[1] & FD_DOR_SELMASK);
2136     cur_drv = get_cur_drv(fdctrl);
2137     if (fdctrl->fifo[2] > cur_drv->track) {
2138         fd_seek(cur_drv, cur_drv->head, 0, cur_drv->sect, 1);
2139     } else {
2140         fd_seek(cur_drv, cur_drv->head,
2141                 cur_drv->track - fdctrl->fifo[2], cur_drv->sect, 1);
2142     }
2143     fdctrl_to_command_phase(fdctrl);
2144     /* Raise Interrupt */
2145     fdctrl->status0 |= FD_SR0_SEEK;
2146     fdctrl_raise_irq(fdctrl);
2147 }
2148 
2149 /*
2150  * Handlers for the execution phase of each command
2151  */
2152 typedef struct FDCtrlCommand {
2153     uint8_t value;
2154     uint8_t mask;
2155     const char* name;
2156     int parameters;
2157     void (*handler)(FDCtrl *fdctrl, int direction);
2158     int direction;
2159 } FDCtrlCommand;
2160 
2161 static const FDCtrlCommand handlers[] = {
2162     { FD_CMD_READ, 0x1f, "READ", 8, fdctrl_start_transfer, FD_DIR_READ },
2163     { FD_CMD_WRITE, 0x3f, "WRITE", 8, fdctrl_start_transfer, FD_DIR_WRITE },
2164     { FD_CMD_SEEK, 0xff, "SEEK", 2, fdctrl_handle_seek },
2165     { FD_CMD_SENSE_INTERRUPT_STATUS, 0xff, "SENSE INTERRUPT STATUS", 0, fdctrl_handle_sense_interrupt_status },
2166     { FD_CMD_RECALIBRATE, 0xff, "RECALIBRATE", 1, fdctrl_handle_recalibrate },
2167     { FD_CMD_FORMAT_TRACK, 0xbf, "FORMAT TRACK", 5, fdctrl_handle_format_track },
2168     { FD_CMD_READ_TRACK, 0xbf, "READ TRACK", 8, fdctrl_start_transfer, FD_DIR_READ },
2169     { FD_CMD_RESTORE, 0xff, "RESTORE", 17, fdctrl_handle_restore }, /* part of READ DELETED DATA */
2170     { FD_CMD_SAVE, 0xff, "SAVE", 0, fdctrl_handle_save }, /* part of READ DELETED DATA */
2171     { FD_CMD_READ_DELETED, 0x1f, "READ DELETED DATA", 8, fdctrl_start_transfer_del, FD_DIR_READ },
2172     { FD_CMD_SCAN_EQUAL, 0x1f, "SCAN EQUAL", 8, fdctrl_start_transfer, FD_DIR_SCANE },
2173     { FD_CMD_VERIFY, 0x1f, "VERIFY", 8, fdctrl_start_transfer, FD_DIR_VERIFY },
2174     { FD_CMD_SCAN_LOW_OR_EQUAL, 0x1f, "SCAN LOW OR EQUAL", 8, fdctrl_start_transfer, FD_DIR_SCANL },
2175     { FD_CMD_SCAN_HIGH_OR_EQUAL, 0x1f, "SCAN HIGH OR EQUAL", 8, fdctrl_start_transfer, FD_DIR_SCANH },
2176     { FD_CMD_WRITE_DELETED, 0x3f, "WRITE DELETED DATA", 8, fdctrl_start_transfer_del, FD_DIR_WRITE },
2177     { FD_CMD_READ_ID, 0xbf, "READ ID", 1, fdctrl_handle_readid },
2178     { FD_CMD_SPECIFY, 0xff, "SPECIFY", 2, fdctrl_handle_specify },
2179     { FD_CMD_SENSE_DRIVE_STATUS, 0xff, "SENSE DRIVE STATUS", 1, fdctrl_handle_sense_drive_status },
2180     { FD_CMD_PERPENDICULAR_MODE, 0xff, "PERPENDICULAR MODE", 1, fdctrl_handle_perpendicular_mode },
2181     { FD_CMD_CONFIGURE, 0xff, "CONFIGURE", 3, fdctrl_handle_configure },
2182     { FD_CMD_POWERDOWN_MODE, 0xff, "POWERDOWN MODE", 2, fdctrl_handle_powerdown_mode },
2183     { FD_CMD_OPTION, 0xff, "OPTION", 1, fdctrl_handle_option },
2184     { FD_CMD_DRIVE_SPECIFICATION_COMMAND, 0xff, "DRIVE SPECIFICATION COMMAND", 5, fdctrl_handle_drive_specification_command },
2185     { FD_CMD_RELATIVE_SEEK_OUT, 0xff, "RELATIVE SEEK OUT", 2, fdctrl_handle_relative_seek_out },
2186     { FD_CMD_FORMAT_AND_WRITE, 0xff, "FORMAT AND WRITE", 10, fdctrl_unimplemented },
2187     { FD_CMD_RELATIVE_SEEK_IN, 0xff, "RELATIVE SEEK IN", 2, fdctrl_handle_relative_seek_in },
2188     { FD_CMD_LOCK, 0x7f, "LOCK", 0, fdctrl_handle_lock },
2189     { FD_CMD_DUMPREG, 0xff, "DUMPREG", 0, fdctrl_handle_dumpreg },
2190     { FD_CMD_VERSION, 0xff, "VERSION", 0, fdctrl_handle_version },
2191     { FD_CMD_PART_ID, 0xff, "PART ID", 0, fdctrl_handle_partid },
2192     { FD_CMD_WRITE, 0x1f, "WRITE (BeOS)", 8, fdctrl_start_transfer, FD_DIR_WRITE }, /* not in specification ; BeOS 4.5 bug */
2193     { 0, 0, "unknown", 0, fdctrl_unimplemented }, /* default handler */
2194 };
2195 /* Associate command to an index in the 'handlers' array */
2196 static uint8_t command_to_handler[256];
2197 
2198 static const FDCtrlCommand *get_command(uint8_t cmd)
2199 {
2200     int idx;
2201 
2202     idx = command_to_handler[cmd];
2203     FLOPPY_DPRINTF("%s command\n", handlers[idx].name);
2204     return &handlers[idx];
2205 }
2206 
2207 static void fdctrl_write_data(FDCtrl *fdctrl, uint32_t value)
2208 {
2209     FDrive *cur_drv;
2210     const FDCtrlCommand *cmd;
2211     uint32_t pos;
2212 
2213     /* Reset mode */
2214     if (!(fdctrl->dor & FD_DOR_nRESET)) {
2215         FLOPPY_DPRINTF("Floppy controller in RESET state !\n");
2216         return;
2217     }
2218     if (!(fdctrl->msr & FD_MSR_RQM) || (fdctrl->msr & FD_MSR_DIO)) {
2219         FLOPPY_DPRINTF("error: controller not ready for writing\n");
2220         return;
2221     }
2222     fdctrl->dsr &= ~FD_DSR_PWRDOWN;
2223 
2224     FLOPPY_DPRINTF("%s: %02x\n", __func__, value);
2225 
2226     /* If data_len spans multiple sectors, the current position in the FIFO
2227      * wraps around while fdctrl->data_pos is the real position in the whole
2228      * request. */
2229     pos = fdctrl->data_pos++;
2230     pos %= FD_SECTOR_LEN;
2231     fdctrl->fifo[pos] = value;
2232 
2233     if (fdctrl->data_pos == fdctrl->data_len) {
2234         fdctrl->msr &= ~FD_MSR_RQM;
2235     }
2236 
2237     switch (fdctrl->phase) {
2238     case FD_PHASE_EXECUTION:
2239         /* For DMA requests, RQM should be cleared during execution phase, so
2240          * we would have errored out above. */
2241         assert(fdctrl->msr & FD_MSR_NONDMA);
2242 
2243         /* FIFO data write */
2244         if (pos == FD_SECTOR_LEN - 1 ||
2245             fdctrl->data_pos == fdctrl->data_len) {
2246             cur_drv = get_cur_drv(fdctrl);
2247             if (blk_pwrite(cur_drv->blk, fd_offset(cur_drv), BDRV_SECTOR_SIZE,
2248                            fdctrl->fifo, 0) < 0) {
2249                 FLOPPY_DPRINTF("error writing sector %d\n",
2250                                fd_sector(cur_drv));
2251                 break;
2252             }
2253             if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv)) {
2254                 FLOPPY_DPRINTF("error seeking to next sector %d\n",
2255                                fd_sector(cur_drv));
2256                 break;
2257             }
2258         }
2259 
2260         /* Switch to result phase when done with the transfer */
2261         if (fdctrl->data_pos == fdctrl->data_len) {
2262             fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
2263         }
2264         break;
2265 
2266     case FD_PHASE_COMMAND:
2267         assert(!(fdctrl->msr & FD_MSR_NONDMA));
2268         assert(fdctrl->data_pos < FD_SECTOR_LEN);
2269 
2270         if (pos == 0) {
2271             /* The first byte specifies the command. Now we start reading
2272              * as many parameters as this command requires. */
2273             cmd = get_command(value);
2274             fdctrl->data_len = cmd->parameters + 1;
2275             if (cmd->parameters) {
2276                 fdctrl->msr |= FD_MSR_RQM;
2277             }
2278             fdctrl->msr |= FD_MSR_CMDBUSY;
2279         }
2280 
2281         if (fdctrl->data_pos == fdctrl->data_len) {
2282             /* We have all parameters now, execute the command */
2283             fdctrl->phase = FD_PHASE_EXECUTION;
2284 
2285             if (fdctrl->data_state & FD_STATE_FORMAT) {
2286                 fdctrl_format_sector(fdctrl);
2287                 break;
2288             }
2289 
2290             cmd = get_command(fdctrl->fifo[0]);
2291             FLOPPY_DPRINTF("Calling handler for '%s'\n", cmd->name);
2292             cmd->handler(fdctrl, cmd->direction);
2293         }
2294         break;
2295 
2296     case FD_PHASE_RESULT:
2297     default:
2298         abort();
2299     }
2300 }
2301 
2302 static void fdctrl_result_timer(void *opaque)
2303 {
2304     FDCtrl *fdctrl = opaque;
2305     FDrive *cur_drv = get_cur_drv(fdctrl);
2306 
2307     /* Pretend we are spinning.
2308      * This is needed for Coherent, which uses READ ID to check for
2309      * sector interleaving.
2310      */
2311     if (cur_drv->last_sect != 0) {
2312         cur_drv->sect = (cur_drv->sect % cur_drv->last_sect) + 1;
2313     }
2314     /* READ_ID can't automatically succeed! */
2315     if ((fdctrl->dsr & FD_DSR_DRATEMASK) != cur_drv->media_rate) {
2316         FLOPPY_DPRINTF("read id rate mismatch (fdc=%d, media=%d)\n",
2317                        fdctrl->dsr & FD_DSR_DRATEMASK, cur_drv->media_rate);
2318         fdctrl_stop_transfer(fdctrl, FD_SR0_ABNTERM, FD_SR1_MA, 0x00);
2319     } else {
2320         fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
2321     }
2322 }
2323 
2324 /* Init functions */
2325 
2326 void fdctrl_init_drives(FloppyBus *bus, DriveInfo **fds)
2327 {
2328     DeviceState *dev;
2329     int i;
2330 
2331     for (i = 0; i < MAX_FD; i++) {
2332         if (fds[i]) {
2333             dev = qdev_new("floppy");
2334             qdev_prop_set_uint32(dev, "unit", i);
2335             qdev_prop_set_enum(dev, "drive-type", FLOPPY_DRIVE_TYPE_AUTO);
2336             qdev_prop_set_drive_err(dev, "drive", blk_by_legacy_dinfo(fds[i]),
2337                                     &error_fatal);
2338             qdev_realize_and_unref(dev, &bus->bus, &error_fatal);
2339         }
2340     }
2341 }
2342 
2343 void fdctrl_realize_common(DeviceState *dev, FDCtrl *fdctrl, Error **errp)
2344 {
2345     int i, j;
2346     FDrive *drive;
2347     static int command_tables_inited = 0;
2348 
2349     if (fdctrl->fallback == FLOPPY_DRIVE_TYPE_AUTO) {
2350         error_setg(errp, "Cannot choose a fallback FDrive type of 'auto'");
2351         return;
2352     }
2353 
2354     /* Fill 'command_to_handler' lookup table */
2355     if (!command_tables_inited) {
2356         command_tables_inited = 1;
2357         for (i = ARRAY_SIZE(handlers) - 1; i >= 0; i--) {
2358             for (j = 0; j < sizeof(command_to_handler); j++) {
2359                 if ((j & handlers[i].mask) == handlers[i].value) {
2360                     command_to_handler[j] = i;
2361                 }
2362             }
2363         }
2364     }
2365 
2366     FLOPPY_DPRINTF("init controller\n");
2367     fdctrl->fifo = qemu_memalign(512, FD_SECTOR_LEN);
2368     memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
2369     fdctrl->fifo_size = 512;
2370     fdctrl->result_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
2371                                              fdctrl_result_timer, fdctrl);
2372 
2373     fdctrl->version = 0x90; /* Intel 82078 controller */
2374     fdctrl->config = FD_CONFIG_EIS | FD_CONFIG_EFIFO; /* Implicit seek, polling & FIFO enabled */
2375     fdctrl->num_floppies = MAX_FD;
2376 
2377     floppy_bus_create(fdctrl, &fdctrl->bus, dev);
2378 
2379     for (i = 0; i < MAX_FD; i++) {
2380         drive = &fdctrl->drives[i];
2381         drive->fdctrl = fdctrl;
2382         fd_init(drive);
2383         fd_revalidate(drive);
2384     }
2385 }
2386 
2387 static void fdc_register_types(void)
2388 {
2389     type_register_static(&floppy_bus_info);
2390     type_register_static(&floppy_drive_info);
2391 }
2392 
2393 type_init(fdc_register_types)
2394