xref: /linux/drivers/block/ataflop.c (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  drivers/block/ataflop.c
4  *
5  *  Copyright (C) 1993  Greg Harp
6  *  Atari Support by Bjoern Brauel, Roman Hodek
7  *
8  *  Big cleanup Sep 11..14 1994 Roman Hodek:
9  *   - Driver now works interrupt driven
10  *   - Support for two drives; should work, but I cannot test that :-(
11  *   - Reading is done in whole tracks and buffered to speed up things
12  *   - Disk change detection and drive deselecting after motor-off
13  *     similar to TOS
14  *   - Autodetection of disk format (DD/HD); untested yet, because I
15  *     don't have an HD drive :-(
16  *
17  *  Fixes Nov 13 1994 Martin Schaller:
18  *   - Autodetection works now
19  *   - Support for 5 1/4'' disks
20  *   - Removed drive type (unknown on atari)
21  *   - Do seeks with 8 Mhz
22  *
23  *  Changes by Andreas Schwab:
24  *   - After errors in multiple read mode try again reading single sectors
25  *  (Feb 1995):
26  *   - Clean up error handling
27  *   - Set blk_size for proper size checking
28  *   - Initialize track register when testing presence of floppy
29  *   - Implement some ioctl's
30  *
31  *  Changes by Torsten Lang:
32  *   - When probing the floppies we should add the FDCCMDADD_H flag since
33  *     the FDC will otherwise wait forever when no disk is inserted...
34  *
35  * ++ Freddi Aschwanden (fa) 20.9.95 fixes for medusa:
36  *  - MFPDELAY() after each FDC access -> atari
37  *  - more/other disk formats
38  *  - DMA to the block buffer directly if we have a 32bit DMA
39  *  - for medusa, the step rate is always 3ms
40  *  - on medusa, use only cache_push()
41  * Roman:
42  *  - Make disk format numbering independent from minors
43  *  - Let user set max. supported drive type (speeds up format
44  *    detection, saves buffer space)
45  *
46  * Roman 10/15/95:
47  *  - implement some more ioctls
48  *  - disk formatting
49  *
50  * Andreas 95/12/12:
51  *  - increase gap size at start of track for HD/ED disks
52  *
53  * Michael (MSch) 11/07/96:
54  *  - implemented FDSETPRM and FDDEFPRM ioctl
55  *
56  * Andreas (97/03/19):
57  *  - implemented missing BLK* ioctls
58  *
59  *  Things left to do:
60  *   - Formatting
61  *   - Maybe a better strategy for disk change detection (does anyone
62  *     know one?)
63  */
64 
65 #include <linux/module.h>
66 
67 #include <linux/fd.h>
68 #include <linux/delay.h>
69 #include <linux/init.h>
70 #include <linux/blk-mq.h>
71 #include <linux/mutex.h>
72 #include <linux/completion.h>
73 #include <linux/wait.h>
74 
75 #include <asm/atariints.h>
76 #include <asm/atari_stdma.h>
77 #include <asm/atari_stram.h>
78 
79 #define	FD_MAX_UNITS 2
80 
81 #undef DEBUG
82 
83 static DEFINE_MUTEX(ataflop_mutex);
84 static struct request *fd_request;
85 
86 /*
87  * WD1772 stuff
88  */
89 
90 /* register codes */
91 
92 #define FDCSELREG_STP   (0x80)   /* command/status register */
93 #define FDCSELREG_TRA   (0x82)   /* track register */
94 #define FDCSELREG_SEC   (0x84)   /* sector register */
95 #define FDCSELREG_DTA   (0x86)   /* data register */
96 
97 /* register names for FDC_READ/WRITE macros */
98 
99 #define FDCREG_CMD		0
100 #define FDCREG_STATUS	0
101 #define FDCREG_TRACK	2
102 #define FDCREG_SECTOR	4
103 #define FDCREG_DATA		6
104 
105 /* command opcodes */
106 
107 #define FDCCMD_RESTORE  (0x00)   /*  -                   */
108 #define FDCCMD_SEEK     (0x10)   /*   |                  */
109 #define FDCCMD_STEP     (0x20)   /*   |  TYP 1 Commands  */
110 #define FDCCMD_STIN     (0x40)   /*   |                  */
111 #define FDCCMD_STOT     (0x60)   /*  -                   */
112 #define FDCCMD_RDSEC    (0x80)   /*  -   TYP 2 Commands  */
113 #define FDCCMD_WRSEC    (0xa0)   /*  -          "        */
114 #define FDCCMD_RDADR    (0xc0)   /*  -                   */
115 #define FDCCMD_RDTRA    (0xe0)   /*   |  TYP 3 Commands  */
116 #define FDCCMD_WRTRA    (0xf0)   /*  -                   */
117 #define FDCCMD_FORCI    (0xd0)   /*  -   TYP 4 Command   */
118 
119 /* command modifier bits */
120 
121 #define FDCCMDADD_SR6   (0x00)   /* step rate settings */
122 #define FDCCMDADD_SR12  (0x01)
123 #define FDCCMDADD_SR2   (0x02)
124 #define FDCCMDADD_SR3   (0x03)
125 #define FDCCMDADD_V     (0x04)   /* verify */
126 #define FDCCMDADD_H     (0x08)   /* wait for spin-up */
127 #define FDCCMDADD_U     (0x10)   /* update track register */
128 #define FDCCMDADD_M     (0x10)   /* multiple sector access */
129 #define FDCCMDADD_E     (0x04)   /* head settling flag */
130 #define FDCCMDADD_P     (0x02)   /* precompensation off */
131 #define FDCCMDADD_A0    (0x01)   /* DAM flag */
132 
133 /* status register bits */
134 
135 #define	FDCSTAT_MOTORON	(0x80)   /* motor on */
136 #define	FDCSTAT_WPROT	(0x40)   /* write protected (FDCCMD_WR*) */
137 #define	FDCSTAT_SPINUP	(0x20)   /* motor speed stable (Type I) */
138 #define	FDCSTAT_DELDAM	(0x20)   /* sector has deleted DAM (Type II+III) */
139 #define	FDCSTAT_RECNF	(0x10)   /* record not found */
140 #define	FDCSTAT_CRC		(0x08)   /* CRC error */
141 #define	FDCSTAT_TR00	(0x04)   /* Track 00 flag (Type I) */
142 #define	FDCSTAT_LOST	(0x04)   /* Lost Data (Type II+III) */
143 #define	FDCSTAT_IDX		(0x02)   /* Index status (Type I) */
144 #define	FDCSTAT_DRQ		(0x02)   /* DRQ status (Type II+III) */
145 #define	FDCSTAT_BUSY	(0x01)   /* FDC is busy */
146 
147 
148 /* PSG Port A Bit Nr 0 .. Side Sel .. 0 -> Side 1  1 -> Side 2 */
149 #define DSKSIDE     (0x01)
150 
151 #define DSKDRVNONE  (0x06)
152 #define DSKDRV0     (0x02)
153 #define DSKDRV1     (0x04)
154 
155 /* step rates */
156 #define	FDCSTEP_6	0x00
157 #define	FDCSTEP_12	0x01
158 #define	FDCSTEP_2	0x02
159 #define	FDCSTEP_3	0x03
160 
161 struct atari_format_descr {
162 	int track;		/* to be formatted */
163 	int head;		/*   ""     ""     */
164 	int sect_offset;	/* offset of first sector */
165 };
166 
167 /* Disk types: DD, HD, ED */
168 static struct atari_disk_type {
169 	const char	*name;
170 	unsigned	spt;		/* sectors per track */
171 	unsigned	blocks;		/* total number of blocks */
172 	unsigned	fdc_speed;	/* fdc_speed setting */
173 	unsigned 	stretch;	/* track doubling ? */
174 } atari_disk_type[] = {
175 	{ "d360",  9, 720, 0, 0},	/*  0: 360kB diskette */
176 	{ "D360",  9, 720, 0, 1},	/*  1: 360kb in 720k or 1.2MB drive */
177 	{ "D720",  9,1440, 0, 0},	/*  2: 720kb in 720k or 1.2MB drive */
178 	{ "D820", 10,1640, 0, 0},	/*  3: DD disk with 82 tracks/10 sectors */
179 /* formats above are probed for type DD */
180 #define	MAX_TYPE_DD 3
181 	{ "h1200",15,2400, 3, 0},	/*  4: 1.2MB diskette */
182 	{ "H1440",18,2880, 3, 0},	/*  5: 1.4 MB diskette (HD) */
183 	{ "H1640",20,3280, 3, 0},	/*  6: 1.64MB diskette (fat HD) 82 tr 20 sec */
184 /* formats above are probed for types DD and HD */
185 #define	MAX_TYPE_HD 6
186 	{ "E2880",36,5760, 3, 0},	/*  7: 2.8 MB diskette (ED) */
187 	{ "E3280",40,6560, 3, 0},	/*  8: 3.2 MB diskette (fat ED) 82 tr 40 sec */
188 /* formats above are probed for types DD, HD and ED */
189 #define	MAX_TYPE_ED 8
190 /* types below are never autoprobed */
191 	{ "H1680",21,3360, 3, 0},	/*  9: 1.68MB diskette (fat HD) 80 tr 21 sec */
192 	{ "h410",10,820, 0, 1},		/* 10: 410k diskette 41 tr 10 sec, stretch */
193 	{ "h1476",18,2952, 3, 0},	/* 11: 1.48MB diskette 82 tr 18 sec */
194 	{ "H1722",21,3444, 3, 0},	/* 12: 1.72MB diskette 82 tr 21 sec */
195 	{ "h420",10,840, 0, 1},		/* 13: 420k diskette 42 tr 10 sec, stretch */
196 	{ "H830",10,1660, 0, 0},	/* 14: 820k diskette 83 tr 10 sec */
197 	{ "h1494",18,2952, 3, 0},	/* 15: 1.49MB diskette 83 tr 18 sec */
198 	{ "H1743",21,3486, 3, 0},	/* 16: 1.74MB diskette 83 tr 21 sec */
199 	{ "h880",11,1760, 0, 0},	/* 17: 880k diskette 80 tr 11 sec */
200 	{ "D1040",13,2080, 0, 0},	/* 18: 1.04MB diskette 80 tr 13 sec */
201 	{ "D1120",14,2240, 0, 0},	/* 19: 1.12MB diskette 80 tr 14 sec */
202 	{ "h1600",20,3200, 3, 0},	/* 20: 1.60MB diskette 80 tr 20 sec */
203 	{ "H1760",22,3520, 3, 0},	/* 21: 1.76MB diskette 80 tr 22 sec */
204 	{ "H1920",24,3840, 3, 0},	/* 22: 1.92MB diskette 80 tr 24 sec */
205 	{ "E3200",40,6400, 3, 0},	/* 23: 3.2MB diskette 80 tr 40 sec */
206 	{ "E3520",44,7040, 3, 0},	/* 24: 3.52MB diskette 80 tr 44 sec */
207 	{ "E3840",48,7680, 3, 0},	/* 25: 3.84MB diskette 80 tr 48 sec */
208 	{ "H1840",23,3680, 3, 0},	/* 26: 1.84MB diskette 80 tr 23 sec */
209 	{ "D800",10,1600, 0, 0},	/* 27: 800k diskette 80 tr 10 sec */
210 };
211 
212 static int StartDiskType[] = {
213 	MAX_TYPE_DD,
214 	MAX_TYPE_HD,
215 	MAX_TYPE_ED
216 };
217 
218 #define	TYPE_DD		0
219 #define	TYPE_HD		1
220 #define	TYPE_ED		2
221 
222 static int DriveType = TYPE_HD;
223 
224 static DEFINE_SPINLOCK(ataflop_lock);
225 
226 /* Array for translating minors into disk formats */
227 static struct {
228 	int 	 index;
229 	unsigned drive_types;
230 } minor2disktype[] = {
231 	{  0, TYPE_DD },	/*  1: d360 */
232 	{  4, TYPE_HD },	/*  2: h1200 */
233 	{  1, TYPE_DD },	/*  3: D360 */
234 	{  2, TYPE_DD },	/*  4: D720 */
235 	{  1, TYPE_DD },	/*  5: h360 = D360 */
236 	{  2, TYPE_DD },	/*  6: h720 = D720 */
237 	{  5, TYPE_HD },	/*  7: H1440 */
238 	{  7, TYPE_ED },	/*  8: E2880 */
239 /* some PC formats :-) */
240 	{  8, TYPE_ED },	/*  9: E3280    <- was "CompaQ" == E2880 for PC */
241 	{  5, TYPE_HD },	/* 10: h1440 = H1440 */
242 	{  9, TYPE_HD },	/* 11: H1680 */
243 	{ 10, TYPE_DD },	/* 12: h410  */
244 	{  3, TYPE_DD },	/* 13: H820     <- == D820, 82x10 */
245 	{ 11, TYPE_HD },	/* 14: h1476 */
246 	{ 12, TYPE_HD },	/* 15: H1722 */
247 	{ 13, TYPE_DD },	/* 16: h420  */
248 	{ 14, TYPE_DD },	/* 17: H830  */
249 	{ 15, TYPE_HD },	/* 18: h1494 */
250 	{ 16, TYPE_HD },	/* 19: H1743 */
251 	{ 17, TYPE_DD },	/* 20: h880  */
252 	{ 18, TYPE_DD },	/* 21: D1040 */
253 	{ 19, TYPE_DD },	/* 22: D1120 */
254 	{ 20, TYPE_HD },	/* 23: h1600 */
255 	{ 21, TYPE_HD },	/* 24: H1760 */
256 	{ 22, TYPE_HD },	/* 25: H1920 */
257 	{ 23, TYPE_ED },	/* 26: E3200 */
258 	{ 24, TYPE_ED },	/* 27: E3520 */
259 	{ 25, TYPE_ED },	/* 28: E3840 */
260 	{ 26, TYPE_HD },	/* 29: H1840 */
261 	{ 27, TYPE_DD },	/* 30: D800  */
262 	{  6, TYPE_HD },	/* 31: H1640    <- was H1600 == h1600 for PC */
263 };
264 
265 #define NUM_DISK_MINORS ARRAY_SIZE(minor2disktype)
266 
267 /*
268  * Maximum disk size (in kilobytes). This default is used whenever the
269  * current disk size is unknown.
270  */
271 #define MAX_DISK_SIZE 3280
272 
273 /*
274  * MSch: User-provided type information. 'drive' points to
275  * the respective entry of this array. Set by FDSETPRM ioctls.
276  */
277 static struct atari_disk_type user_params[FD_MAX_UNITS];
278 
279 /*
280  * User-provided permanent type information. 'drive' points to
281  * the respective entry of this array.  Set by FDDEFPRM ioctls,
282  * restored upon disk change by floppy_revalidate() if valid (as seen by
283  * default_params[].blocks > 0 - a bit in unit[].flags might be used for this?)
284  */
285 static struct atari_disk_type default_params[FD_MAX_UNITS];
286 
287 /* current info on each unit */
288 static struct atari_floppy_struct {
289 	int connected;				/* !=0 : drive is connected */
290 	int autoprobe;				/* !=0 : do autoprobe	    */
291 
292 	struct atari_disk_type	*disktype;	/* current type of disk */
293 
294 	int track;		/* current head position or -1 if
295 				   unknown */
296 	unsigned int steprate;	/* steprate setting */
297 	unsigned int wpstat;	/* current state of WP signal (for
298 				   disk change detection) */
299 	int flags;		/* flags */
300 	struct gendisk *disk[NUM_DISK_MINORS];
301 	int ref;
302 	int type;
303 	struct blk_mq_tag_set tag_set;
304 } unit[FD_MAX_UNITS];
305 
306 #define	UD	unit[drive]
307 #define	UDT	unit[drive].disktype
308 #define	SUD	unit[SelectedDrive]
309 #define	SUDT	unit[SelectedDrive].disktype
310 
311 
312 #define FDC_READ(reg) ({			\
313     /* unsigned long __flags; */		\
314     unsigned short __val;			\
315     /* local_irq_save(__flags); */		\
316     dma_wd.dma_mode_status = 0x80 | (reg);	\
317     udelay(25);					\
318     __val = dma_wd.fdc_acces_seccount;		\
319     MFPDELAY();					\
320     /* local_irq_restore(__flags); */		\
321     __val & 0xff;				\
322 })
323 
324 #define FDC_WRITE(reg,val)			\
325     do {					\
326 	/* unsigned long __flags; */		\
327 	/* local_irq_save(__flags); */		\
328 	dma_wd.dma_mode_status = 0x80 | (reg);	\
329 	udelay(25);				\
330 	dma_wd.fdc_acces_seccount = (val);	\
331 	MFPDELAY();				\
332         /* local_irq_restore(__flags); */	\
333     } while(0)
334 
335 
336 /* Buffering variables:
337  * First, there is a DMA buffer in ST-RAM that is used for floppy DMA
338  * operations. Second, a track buffer is used to cache a whole track
339  * of the disk to save read operations. These are two separate buffers
340  * because that allows write operations without clearing the track buffer.
341  */
342 
343 static int MaxSectors[] = {
344 	11, 22, 44
345 };
346 static int BufferSize[] = {
347 	15*512, 30*512, 60*512
348 };
349 
350 #define	BUFFER_SIZE	(BufferSize[DriveType])
351 
352 unsigned char *DMABuffer;			  /* buffer for writes */
353 static unsigned long PhysDMABuffer;   /* physical address */
354 
355 static int UseTrackbuffer = -1;		  /* Do track buffering? */
356 module_param(UseTrackbuffer, int, 0);
357 
358 unsigned char *TrackBuffer;			  /* buffer for reads */
359 static unsigned long PhysTrackBuffer; /* physical address */
360 static int BufferDrive, BufferSide, BufferTrack;
361 static int read_track;		/* non-zero if we are reading whole tracks */
362 
363 #define	SECTOR_BUFFER(sec)	(TrackBuffer + ((sec)-1)*512)
364 #define	IS_BUFFERED(drive,side,track) \
365     (BufferDrive == (drive) && BufferSide == (side) && BufferTrack == (track))
366 
367 /*
368  * These are global variables, as that's the easiest way to give
369  * information to interrupts. They are the data used for the current
370  * request.
371  */
372 static int SelectedDrive = 0;
373 static int ReqCmd, ReqBlock;
374 static int ReqSide, ReqTrack, ReqSector, ReqCnt;
375 static int HeadSettleFlag = 0;
376 static unsigned char *ReqData, *ReqBuffer;
377 static int MotorOn = 0, MotorOffTrys;
378 static int IsFormatting = 0, FormatError;
379 
380 static int UserSteprate[FD_MAX_UNITS] = { -1, -1 };
381 module_param_array(UserSteprate, int, NULL, 0);
382 
383 static DECLARE_COMPLETION(format_wait);
384 
385 static unsigned long changed_floppies = 0xff, fake_change = 0;
386 #define	CHECK_CHANGE_DELAY	HZ/2
387 
388 #define	FD_MOTOR_OFF_DELAY	(3*HZ)
389 #define	FD_MOTOR_OFF_MAXTRY	(10*20)
390 
391 #define FLOPPY_TIMEOUT		(6*HZ)
392 #define RECALIBRATE_ERRORS	4	/* After this many errors the drive
393 					 * will be recalibrated. */
394 #define MAX_ERRORS		8	/* After this many errors the driver
395 					 * will give up. */
396 
397 
398 /*
399  * The driver is trying to determine the correct media format
400  * while Probing is set. fd_rwsec_done() clears it after a
401  * successful access.
402  */
403 static int Probing = 0;
404 
405 /* This flag is set when a dummy seek is necessary to make the WP
406  * status bit accessible.
407  */
408 static int NeedSeek = 0;
409 
410 
411 #ifdef DEBUG
412 #define DPRINT(a)	printk a
413 #else
414 #define DPRINT(a)
415 #endif
416 
417 /***************************** Prototypes *****************************/
418 
419 static void fd_select_side( int side );
420 static void fd_select_drive( int drive );
421 static void fd_deselect( void );
422 static void fd_motor_off_timer(struct timer_list *unused);
423 static void check_change(struct timer_list *unused);
424 static irqreturn_t floppy_irq (int irq, void *dummy);
425 static void fd_error( void );
426 static int do_format(int drive, int type, struct atari_format_descr *desc);
427 static void do_fd_action( int drive );
428 static void fd_calibrate( void );
429 static void fd_calibrate_done( int status );
430 static void fd_seek( void );
431 static void fd_seek_done( int status );
432 static void fd_rwsec( void );
433 static void fd_readtrack_check(struct timer_list *unused);
434 static void fd_rwsec_done( int status );
435 static void fd_rwsec_done1(int status);
436 static void fd_writetrack( void );
437 static void fd_writetrack_done( int status );
438 static void fd_times_out(struct timer_list *unused);
439 static void finish_fdc( void );
440 static void finish_fdc_done( int dummy );
441 static void setup_req_params( int drive );
442 static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int
443                      cmd, unsigned long param);
444 static void fd_probe( int drive );
445 static int fd_test_drive_present( int drive );
446 static void config_types( void );
447 static int floppy_open(struct block_device *bdev, fmode_t mode);
448 static void floppy_release(struct gendisk *disk, fmode_t mode);
449 
450 /************************* End of Prototypes **************************/
451 
452 static DEFINE_TIMER(motor_off_timer, fd_motor_off_timer);
453 static DEFINE_TIMER(readtrack_timer, fd_readtrack_check);
454 static DEFINE_TIMER(timeout_timer, fd_times_out);
455 static DEFINE_TIMER(fd_timer, check_change);
456 
457 static void fd_end_request_cur(blk_status_t err)
458 {
459 	if (!blk_update_request(fd_request, err,
460 				blk_rq_cur_bytes(fd_request))) {
461 		__blk_mq_end_request(fd_request, err);
462 		fd_request = NULL;
463 	}
464 }
465 
466 static inline void start_motor_off_timer(void)
467 {
468 	mod_timer(&motor_off_timer, jiffies + FD_MOTOR_OFF_DELAY);
469 	MotorOffTrys = 0;
470 }
471 
472 static inline void start_check_change_timer( void )
473 {
474 	mod_timer(&fd_timer, jiffies + CHECK_CHANGE_DELAY);
475 }
476 
477 static inline void start_timeout(void)
478 {
479 	mod_timer(&timeout_timer, jiffies + FLOPPY_TIMEOUT);
480 }
481 
482 static inline void stop_timeout(void)
483 {
484 	del_timer(&timeout_timer);
485 }
486 
487 /* Select the side to use. */
488 
489 static void fd_select_side( int side )
490 {
491 	unsigned long flags;
492 
493 	/* protect against various other ints mucking around with the PSG */
494 	local_irq_save(flags);
495 
496 	sound_ym.rd_data_reg_sel = 14; /* Select PSG Port A */
497 	sound_ym.wd_data = (side == 0) ? sound_ym.rd_data_reg_sel | 0x01 :
498 	                                 sound_ym.rd_data_reg_sel & 0xfe;
499 
500 	local_irq_restore(flags);
501 }
502 
503 
504 /* Select a drive, update the FDC's track register and set the correct
505  * clock speed for this disk's type.
506  */
507 
508 static void fd_select_drive( int drive )
509 {
510 	unsigned long flags;
511 	unsigned char tmp;
512 
513 	if (drive == SelectedDrive)
514 	  return;
515 
516 	/* protect against various other ints mucking around with the PSG */
517 	local_irq_save(flags);
518 	sound_ym.rd_data_reg_sel = 14; /* Select PSG Port A */
519 	tmp = sound_ym.rd_data_reg_sel;
520 	sound_ym.wd_data = (tmp | DSKDRVNONE) & ~(drive == 0 ? DSKDRV0 : DSKDRV1);
521 	atari_dont_touch_floppy_select = 1;
522 	local_irq_restore(flags);
523 
524 	/* restore track register to saved value */
525 	FDC_WRITE( FDCREG_TRACK, UD.track );
526 	udelay(25);
527 
528 	/* select 8/16 MHz */
529 	if (UDT)
530 		if (ATARIHW_PRESENT(FDCSPEED))
531 			dma_wd.fdc_speed = UDT->fdc_speed;
532 
533 	SelectedDrive = drive;
534 }
535 
536 
537 /* Deselect both drives. */
538 
539 static void fd_deselect( void )
540 {
541 	unsigned long flags;
542 
543 	/* protect against various other ints mucking around with the PSG */
544 	local_irq_save(flags);
545 	atari_dont_touch_floppy_select = 0;
546 	sound_ym.rd_data_reg_sel=14;	/* Select PSG Port A */
547 	sound_ym.wd_data = (sound_ym.rd_data_reg_sel |
548 			    (MACH_IS_FALCON ? 3 : 7)); /* no drives selected */
549 	/* On Falcon, the drive B select line is used on the printer port, so
550 	 * leave it alone... */
551 	SelectedDrive = -1;
552 	local_irq_restore(flags);
553 }
554 
555 
556 /* This timer function deselects the drives when the FDC switched the
557  * motor off. The deselection cannot happen earlier because the FDC
558  * counts the index signals, which arrive only if one drive is selected.
559  */
560 
561 static void fd_motor_off_timer(struct timer_list *unused)
562 {
563 	unsigned char status;
564 
565 	if (SelectedDrive < 0)
566 		/* no drive selected, needn't deselect anyone */
567 		return;
568 
569 	if (stdma_islocked())
570 		goto retry;
571 
572 	status = FDC_READ( FDCREG_STATUS );
573 
574 	if (!(status & 0x80)) {
575 		/* motor already turned off by FDC -> deselect drives */
576 		MotorOn = 0;
577 		fd_deselect();
578 		return;
579 	}
580 	/* not yet off, try again */
581 
582   retry:
583 	/* Test again later; if tested too often, it seems there is no disk
584 	 * in the drive and the FDC will leave the motor on forever (or,
585 	 * at least until a disk is inserted). So we'll test only twice
586 	 * per second from then on...
587 	 */
588 	mod_timer(&motor_off_timer,
589 		  jiffies + (MotorOffTrys++ < FD_MOTOR_OFF_MAXTRY ? HZ/20 : HZ/2));
590 }
591 
592 
593 /* This function is repeatedly called to detect disk changes (as good
594  * as possible) and keep track of the current state of the write protection.
595  */
596 
597 static void check_change(struct timer_list *unused)
598 {
599 	static int    drive = 0;
600 
601 	unsigned long flags;
602 	unsigned char old_porta;
603 	int			  stat;
604 
605 	if (++drive > 1 || !UD.connected)
606 		drive = 0;
607 
608 	/* protect against various other ints mucking around with the PSG */
609 	local_irq_save(flags);
610 
611 	if (!stdma_islocked()) {
612 		sound_ym.rd_data_reg_sel = 14;
613 		old_porta = sound_ym.rd_data_reg_sel;
614 		sound_ym.wd_data = (old_porta | DSKDRVNONE) &
615 			               ~(drive == 0 ? DSKDRV0 : DSKDRV1);
616 		stat = !!(FDC_READ( FDCREG_STATUS ) & FDCSTAT_WPROT);
617 		sound_ym.wd_data = old_porta;
618 
619 		if (stat != UD.wpstat) {
620 			DPRINT(( "wpstat[%d] = %d\n", drive, stat ));
621 			UD.wpstat = stat;
622 			set_bit (drive, &changed_floppies);
623 		}
624 	}
625 	local_irq_restore(flags);
626 
627 	start_check_change_timer();
628 }
629 
630 
631 /* Handling of the Head Settling Flag: This flag should be set after each
632  * seek operation, because we don't use seeks with verify.
633  */
634 
635 static inline void set_head_settle_flag(void)
636 {
637 	HeadSettleFlag = FDCCMDADD_E;
638 }
639 
640 static inline int get_head_settle_flag(void)
641 {
642 	int	tmp = HeadSettleFlag;
643 	HeadSettleFlag = 0;
644 	return( tmp );
645 }
646 
647 static inline void copy_buffer(void *from, void *to)
648 {
649 	ulong *p1 = (ulong *)from, *p2 = (ulong *)to;
650 	int cnt;
651 
652 	for (cnt = 512/4; cnt; cnt--)
653 		*p2++ = *p1++;
654 }
655 
656 
657 
658 
659 /* General Interrupt Handling */
660 
661 static void (*FloppyIRQHandler)( int status ) = NULL;
662 
663 static irqreturn_t floppy_irq (int irq, void *dummy)
664 {
665 	unsigned char status;
666 	void (*handler)( int );
667 
668 	handler = xchg(&FloppyIRQHandler, NULL);
669 
670 	if (handler) {
671 		nop();
672 		status = FDC_READ( FDCREG_STATUS );
673 		DPRINT(("FDC irq, status = %02x handler = %08lx\n",status,(unsigned long)handler));
674 		handler( status );
675 	}
676 	else {
677 		DPRINT(("FDC irq, no handler\n"));
678 	}
679 	return IRQ_HANDLED;
680 }
681 
682 
683 /* Error handling: If some error happened, retry some times, then
684  * recalibrate, then try again, and fail after MAX_ERRORS.
685  */
686 
687 static void fd_error( void )
688 {
689 	if (IsFormatting) {
690 		IsFormatting = 0;
691 		FormatError = 1;
692 		complete(&format_wait);
693 		return;
694 	}
695 
696 	if (!fd_request)
697 		return;
698 
699 	fd_request->error_count++;
700 	if (fd_request->error_count >= MAX_ERRORS) {
701 		printk(KERN_ERR "fd%d: too many errors.\n", SelectedDrive );
702 		fd_end_request_cur(BLK_STS_IOERR);
703 	}
704 	else if (fd_request->error_count == RECALIBRATE_ERRORS) {
705 		printk(KERN_WARNING "fd%d: recalibrating\n", SelectedDrive );
706 		if (SelectedDrive != -1)
707 			SUD.track = -1;
708 	}
709 }
710 
711 
712 
713 #define	SET_IRQ_HANDLER(proc) do { FloppyIRQHandler = (proc); } while(0)
714 
715 
716 /* ---------- Formatting ---------- */
717 
718 #define FILL(n,val)		\
719     do {			\
720 	memset( p, val, n );	\
721 	p += n;			\
722     } while(0)
723 
724 static int do_format(int drive, int type, struct atari_format_descr *desc)
725 {
726 	struct request_queue *q;
727 	unsigned char	*p;
728 	int sect, nsect;
729 	unsigned long	flags;
730 	int ret;
731 
732 	if (type) {
733 		type--;
734 		if (type >= NUM_DISK_MINORS ||
735 		    minor2disktype[type].drive_types > DriveType)
736 			return -EINVAL;
737 	}
738 
739 	q = unit[drive].disk[type]->queue;
740 	blk_mq_freeze_queue(q);
741 	blk_mq_quiesce_queue(q);
742 
743 	local_irq_save(flags);
744 	stdma_lock(floppy_irq, NULL);
745 	atari_turnon_irq( IRQ_MFP_FDC ); /* should be already, just to be sure */
746 	local_irq_restore(flags);
747 
748 	if (type) {
749 		type = minor2disktype[type].index;
750 		UDT = &atari_disk_type[type];
751 	}
752 
753 	if (!UDT || desc->track >= UDT->blocks/UDT->spt/2 || desc->head >= 2) {
754 		ret = -EINVAL;
755 		goto out;
756 	}
757 
758 	nsect = UDT->spt;
759 	p = TrackBuffer;
760 	/* The track buffer is used for the raw track data, so its
761 	   contents become invalid! */
762 	BufferDrive = -1;
763 	/* stop deselect timer */
764 	del_timer( &motor_off_timer );
765 
766 	FILL( 60 * (nsect / 9), 0x4e );
767 	for( sect = 0; sect < nsect; ++sect ) {
768 		FILL( 12, 0 );
769 		FILL( 3, 0xf5 );
770 		*p++ = 0xfe;
771 		*p++ = desc->track;
772 		*p++ = desc->head;
773 		*p++ = (nsect + sect - desc->sect_offset) % nsect + 1;
774 		*p++ = 2;
775 		*p++ = 0xf7;
776 		FILL( 22, 0x4e );
777 		FILL( 12, 0 );
778 		FILL( 3, 0xf5 );
779 		*p++ = 0xfb;
780 		FILL( 512, 0xe5 );
781 		*p++ = 0xf7;
782 		FILL( 40, 0x4e );
783 	}
784 	FILL( TrackBuffer+BUFFER_SIZE-p, 0x4e );
785 
786 	IsFormatting = 1;
787 	FormatError = 0;
788 	ReqTrack = desc->track;
789 	ReqSide  = desc->head;
790 	do_fd_action( drive );
791 
792 	wait_for_completion(&format_wait);
793 
794 	ret = FormatError ? -EIO : 0;
795 out:
796 	blk_mq_unquiesce_queue(q);
797 	blk_mq_unfreeze_queue(q);
798 	return ret;
799 }
800 
801 
802 /* do_fd_action() is the general procedure for a fd request: All
803  * required parameter settings (drive select, side select, track
804  * position) are checked and set if needed. For each of these
805  * parameters and the actual reading or writing exist two functions:
806  * one that starts the setting (or skips it if possible) and one
807  * callback for the "done" interrupt. Each done func calls the next
808  * set function to propagate the request down to fd_rwsec_done().
809  */
810 
811 static void do_fd_action( int drive )
812 {
813 	DPRINT(("do_fd_action\n"));
814 
815 	if (UseTrackbuffer && !IsFormatting) {
816 	repeat:
817 	    if (IS_BUFFERED( drive, ReqSide, ReqTrack )) {
818 		if (ReqCmd == READ) {
819 		    copy_buffer( SECTOR_BUFFER(ReqSector), ReqData );
820 		    if (++ReqCnt < blk_rq_cur_sectors(fd_request)) {
821 			/* read next sector */
822 			setup_req_params( drive );
823 			goto repeat;
824 		    }
825 		    else {
826 			/* all sectors finished */
827 			fd_end_request_cur(BLK_STS_OK);
828 			return;
829 		    }
830 		}
831 		else {
832 		    /* cmd == WRITE, pay attention to track buffer
833 		     * consistency! */
834 		    copy_buffer( ReqData, SECTOR_BUFFER(ReqSector) );
835 		}
836 	    }
837 	}
838 
839 	if (SelectedDrive != drive)
840 		fd_select_drive( drive );
841 
842 	if (UD.track == -1)
843 		fd_calibrate();
844 	else if (UD.track != ReqTrack << UDT->stretch)
845 		fd_seek();
846 	else if (IsFormatting)
847 		fd_writetrack();
848 	else
849 		fd_rwsec();
850 }
851 
852 
853 /* Seek to track 0 if the current track is unknown */
854 
855 static void fd_calibrate( void )
856 {
857 	if (SUD.track >= 0) {
858 		fd_calibrate_done( 0 );
859 		return;
860 	}
861 
862 	if (ATARIHW_PRESENT(FDCSPEED))
863 		dma_wd.fdc_speed = 0;   /* always seek with 8 Mhz */
864 	DPRINT(("fd_calibrate\n"));
865 	SET_IRQ_HANDLER( fd_calibrate_done );
866 	/* we can't verify, since the speed may be incorrect */
867 	FDC_WRITE( FDCREG_CMD, FDCCMD_RESTORE | SUD.steprate );
868 
869 	NeedSeek = 1;
870 	MotorOn = 1;
871 	start_timeout();
872 	/* wait for IRQ */
873 }
874 
875 
876 static void fd_calibrate_done( int status )
877 {
878 	DPRINT(("fd_calibrate_done()\n"));
879 	stop_timeout();
880 
881 	/* set the correct speed now */
882 	if (ATARIHW_PRESENT(FDCSPEED))
883 		dma_wd.fdc_speed = SUDT->fdc_speed;
884 	if (status & FDCSTAT_RECNF) {
885 		printk(KERN_ERR "fd%d: restore failed\n", SelectedDrive );
886 		fd_error();
887 	}
888 	else {
889 		SUD.track = 0;
890 		fd_seek();
891 	}
892 }
893 
894 
895 /* Seek the drive to the requested track. The drive must have been
896  * calibrated at some point before this.
897  */
898 
899 static void fd_seek( void )
900 {
901 	if (SUD.track == ReqTrack << SUDT->stretch) {
902 		fd_seek_done( 0 );
903 		return;
904 	}
905 
906 	if (ATARIHW_PRESENT(FDCSPEED)) {
907 		dma_wd.fdc_speed = 0;	/* always seek witch 8 Mhz */
908 		MFPDELAY();
909 	}
910 
911 	DPRINT(("fd_seek() to track %d\n",ReqTrack));
912 	FDC_WRITE( FDCREG_DATA, ReqTrack << SUDT->stretch);
913 	udelay(25);
914 	SET_IRQ_HANDLER( fd_seek_done );
915 	FDC_WRITE( FDCREG_CMD, FDCCMD_SEEK | SUD.steprate );
916 
917 	MotorOn = 1;
918 	set_head_settle_flag();
919 	start_timeout();
920 	/* wait for IRQ */
921 }
922 
923 
924 static void fd_seek_done( int status )
925 {
926 	DPRINT(("fd_seek_done()\n"));
927 	stop_timeout();
928 
929 	/* set the correct speed */
930 	if (ATARIHW_PRESENT(FDCSPEED))
931 		dma_wd.fdc_speed = SUDT->fdc_speed;
932 	if (status & FDCSTAT_RECNF) {
933 		printk(KERN_ERR "fd%d: seek error (to track %d)\n",
934 				SelectedDrive, ReqTrack );
935 		/* we don't know exactly which track we are on now! */
936 		SUD.track = -1;
937 		fd_error();
938 	}
939 	else {
940 		SUD.track = ReqTrack << SUDT->stretch;
941 		NeedSeek = 0;
942 		if (IsFormatting)
943 			fd_writetrack();
944 		else
945 			fd_rwsec();
946 	}
947 }
948 
949 
950 /* This does the actual reading/writing after positioning the head
951  * over the correct track.
952  */
953 
954 static int MultReadInProgress = 0;
955 
956 
957 static void fd_rwsec( void )
958 {
959 	unsigned long paddr, flags;
960 	unsigned int  rwflag, old_motoron;
961 	unsigned int track;
962 
963 	DPRINT(("fd_rwsec(), Sec=%d, Access=%c\n",ReqSector, ReqCmd == WRITE ? 'w' : 'r' ));
964 	if (ReqCmd == WRITE) {
965 		if (ATARIHW_PRESENT(EXTD_DMA)) {
966 			paddr = virt_to_phys(ReqData);
967 		}
968 		else {
969 			copy_buffer( ReqData, DMABuffer );
970 			paddr = PhysDMABuffer;
971 		}
972 		dma_cache_maintenance( paddr, 512, 1 );
973 		rwflag = 0x100;
974 	}
975 	else {
976 		if (read_track)
977 			paddr = PhysTrackBuffer;
978 		else
979 			paddr = ATARIHW_PRESENT(EXTD_DMA) ?
980 				virt_to_phys(ReqData) : PhysDMABuffer;
981 		rwflag = 0;
982 	}
983 
984 	fd_select_side( ReqSide );
985 
986 	/* Start sector of this operation */
987 	FDC_WRITE( FDCREG_SECTOR, read_track ? 1 : ReqSector );
988 	MFPDELAY();
989 	/* Cheat for track if stretch != 0 */
990 	if (SUDT->stretch) {
991 		track = FDC_READ( FDCREG_TRACK);
992 		MFPDELAY();
993 		FDC_WRITE( FDCREG_TRACK, track >> SUDT->stretch);
994 	}
995 	udelay(25);
996 
997 	/* Setup DMA */
998 	local_irq_save(flags);
999 	dma_wd.dma_lo = (unsigned char)paddr;
1000 	MFPDELAY();
1001 	paddr >>= 8;
1002 	dma_wd.dma_md = (unsigned char)paddr;
1003 	MFPDELAY();
1004 	paddr >>= 8;
1005 	if (ATARIHW_PRESENT(EXTD_DMA))
1006 		st_dma_ext_dmahi = (unsigned short)paddr;
1007 	else
1008 		dma_wd.dma_hi = (unsigned char)paddr;
1009 	MFPDELAY();
1010 	local_irq_restore(flags);
1011 
1012 	/* Clear FIFO and switch DMA to correct mode */
1013 	dma_wd.dma_mode_status = 0x90 | rwflag;
1014 	MFPDELAY();
1015 	dma_wd.dma_mode_status = 0x90 | (rwflag ^ 0x100);
1016 	MFPDELAY();
1017 	dma_wd.dma_mode_status = 0x90 | rwflag;
1018 	MFPDELAY();
1019 
1020 	/* How many sectors for DMA */
1021 	dma_wd.fdc_acces_seccount = read_track ? SUDT->spt : 1;
1022 
1023 	udelay(25);
1024 
1025 	/* Start operation */
1026 	dma_wd.dma_mode_status = FDCSELREG_STP | rwflag;
1027 	udelay(25);
1028 	SET_IRQ_HANDLER( fd_rwsec_done );
1029 	dma_wd.fdc_acces_seccount =
1030 	  (get_head_settle_flag() |
1031 	   (rwflag ? FDCCMD_WRSEC : (FDCCMD_RDSEC | (read_track ? FDCCMDADD_M : 0))));
1032 
1033 	old_motoron = MotorOn;
1034 	MotorOn = 1;
1035 	NeedSeek = 1;
1036 	/* wait for interrupt */
1037 
1038 	if (read_track) {
1039 		/* If reading a whole track, wait about one disk rotation and
1040 		 * then check if all sectors are read. The FDC will even
1041 		 * search for the first non-existent sector and need 1 sec to
1042 		 * recognise that it isn't present :-(
1043 		 */
1044 		MultReadInProgress = 1;
1045 		mod_timer(&readtrack_timer,
1046 			  /* 1 rot. + 5 rot.s if motor was off  */
1047 			  jiffies + HZ/5 + (old_motoron ? 0 : HZ));
1048 	}
1049 	start_timeout();
1050 }
1051 
1052 
1053 static void fd_readtrack_check(struct timer_list *unused)
1054 {
1055 	unsigned long flags, addr, addr2;
1056 
1057 	local_irq_save(flags);
1058 
1059 	if (!MultReadInProgress) {
1060 		/* This prevents a race condition that could arise if the
1061 		 * interrupt is triggered while the calling of this timer
1062 		 * callback function takes place. The IRQ function then has
1063 		 * already cleared 'MultReadInProgress'  when flow of control
1064 		 * gets here.
1065 		 */
1066 		local_irq_restore(flags);
1067 		return;
1068 	}
1069 
1070 	/* get the current DMA address */
1071 	/* ++ f.a. read twice to avoid being fooled by switcher */
1072 	addr = 0;
1073 	do {
1074 		addr2 = addr;
1075 		addr = dma_wd.dma_lo & 0xff;
1076 		MFPDELAY();
1077 		addr |= (dma_wd.dma_md & 0xff) << 8;
1078 		MFPDELAY();
1079 		if (ATARIHW_PRESENT( EXTD_DMA ))
1080 			addr |= (st_dma_ext_dmahi & 0xffff) << 16;
1081 		else
1082 			addr |= (dma_wd.dma_hi & 0xff) << 16;
1083 		MFPDELAY();
1084 	} while(addr != addr2);
1085 
1086 	if (addr >= PhysTrackBuffer + SUDT->spt*512) {
1087 		/* already read enough data, force an FDC interrupt to stop
1088 		 * the read operation
1089 		 */
1090 		SET_IRQ_HANDLER( NULL );
1091 		MultReadInProgress = 0;
1092 		local_irq_restore(flags);
1093 		DPRINT(("fd_readtrack_check(): done\n"));
1094 		FDC_WRITE( FDCREG_CMD, FDCCMD_FORCI );
1095 		udelay(25);
1096 
1097 		/* No error until now -- the FDC would have interrupted
1098 		 * otherwise!
1099 		 */
1100 		fd_rwsec_done1(0);
1101 	}
1102 	else {
1103 		/* not yet finished, wait another tenth rotation */
1104 		local_irq_restore(flags);
1105 		DPRINT(("fd_readtrack_check(): not yet finished\n"));
1106 		mod_timer(&readtrack_timer, jiffies + HZ/5/10);
1107 	}
1108 }
1109 
1110 
1111 static void fd_rwsec_done( int status )
1112 {
1113 	DPRINT(("fd_rwsec_done()\n"));
1114 
1115 	if (read_track) {
1116 		del_timer(&readtrack_timer);
1117 		if (!MultReadInProgress)
1118 			return;
1119 		MultReadInProgress = 0;
1120 	}
1121 	fd_rwsec_done1(status);
1122 }
1123 
1124 static void fd_rwsec_done1(int status)
1125 {
1126 	unsigned int track;
1127 
1128 	stop_timeout();
1129 
1130 	/* Correct the track if stretch != 0 */
1131 	if (SUDT->stretch) {
1132 		track = FDC_READ( FDCREG_TRACK);
1133 		MFPDELAY();
1134 		FDC_WRITE( FDCREG_TRACK, track << SUDT->stretch);
1135 	}
1136 
1137 	if (!UseTrackbuffer) {
1138 		dma_wd.dma_mode_status = 0x90;
1139 		MFPDELAY();
1140 		if (!(dma_wd.dma_mode_status & 0x01)) {
1141 			printk(KERN_ERR "fd%d: DMA error\n", SelectedDrive );
1142 			goto err_end;
1143 		}
1144 	}
1145 	MFPDELAY();
1146 
1147 	if (ReqCmd == WRITE && (status & FDCSTAT_WPROT)) {
1148 		printk(KERN_NOTICE "fd%d: is write protected\n", SelectedDrive );
1149 		goto err_end;
1150 	}
1151 	if ((status & FDCSTAT_RECNF) &&
1152 	    /* RECNF is no error after a multiple read when the FDC
1153 	       searched for a non-existent sector! */
1154 	    !(read_track && FDC_READ(FDCREG_SECTOR) > SUDT->spt)) {
1155 		if (Probing) {
1156 			if (SUDT > atari_disk_type) {
1157 			    if (SUDT[-1].blocks > ReqBlock) {
1158 				/* try another disk type */
1159 				SUDT--;
1160 				set_capacity(unit[SelectedDrive].disk[0],
1161 							SUDT->blocks);
1162 			    } else
1163 				Probing = 0;
1164 			}
1165 			else {
1166 				if (SUD.flags & FTD_MSG)
1167 					printk(KERN_INFO "fd%d: Auto-detected floppy type %s\n",
1168 					       SelectedDrive, SUDT->name );
1169 				Probing=0;
1170 			}
1171 		} else {
1172 /* record not found, but not probing. Maybe stretch wrong ? Restart probing */
1173 			if (SUD.autoprobe) {
1174 				SUDT = atari_disk_type + StartDiskType[DriveType];
1175 				set_capacity(unit[SelectedDrive].disk[0],
1176 							SUDT->blocks);
1177 				Probing = 1;
1178 			}
1179 		}
1180 		if (Probing) {
1181 			if (ATARIHW_PRESENT(FDCSPEED)) {
1182 				dma_wd.fdc_speed = SUDT->fdc_speed;
1183 				MFPDELAY();
1184 			}
1185 			setup_req_params( SelectedDrive );
1186 			BufferDrive = -1;
1187 			do_fd_action( SelectedDrive );
1188 			return;
1189 		}
1190 
1191 		printk(KERN_ERR "fd%d: sector %d not found (side %d, track %d)\n",
1192 		       SelectedDrive, FDC_READ (FDCREG_SECTOR), ReqSide, ReqTrack );
1193 		goto err_end;
1194 	}
1195 	if (status & FDCSTAT_CRC) {
1196 		printk(KERN_ERR "fd%d: CRC error (side %d, track %d, sector %d)\n",
1197 		       SelectedDrive, ReqSide, ReqTrack, FDC_READ (FDCREG_SECTOR) );
1198 		goto err_end;
1199 	}
1200 	if (status & FDCSTAT_LOST) {
1201 		printk(KERN_ERR "fd%d: lost data (side %d, track %d, sector %d)\n",
1202 		       SelectedDrive, ReqSide, ReqTrack, FDC_READ (FDCREG_SECTOR) );
1203 		goto err_end;
1204 	}
1205 
1206 	Probing = 0;
1207 
1208 	if (ReqCmd == READ) {
1209 		if (!read_track) {
1210 			void *addr;
1211 			addr = ATARIHW_PRESENT( EXTD_DMA ) ? ReqData : DMABuffer;
1212 			dma_cache_maintenance( virt_to_phys(addr), 512, 0 );
1213 			if (!ATARIHW_PRESENT( EXTD_DMA ))
1214 				copy_buffer (addr, ReqData);
1215 		} else {
1216 			dma_cache_maintenance( PhysTrackBuffer, MaxSectors[DriveType] * 512, 0 );
1217 			BufferDrive = SelectedDrive;
1218 			BufferSide  = ReqSide;
1219 			BufferTrack = ReqTrack;
1220 			copy_buffer (SECTOR_BUFFER (ReqSector), ReqData);
1221 		}
1222 	}
1223 
1224 	if (++ReqCnt < blk_rq_cur_sectors(fd_request)) {
1225 		/* read next sector */
1226 		setup_req_params( SelectedDrive );
1227 		do_fd_action( SelectedDrive );
1228 	}
1229 	else {
1230 		/* all sectors finished */
1231 		fd_end_request_cur(BLK_STS_OK);
1232 	}
1233 	return;
1234 
1235   err_end:
1236 	BufferDrive = -1;
1237 	fd_error();
1238 }
1239 
1240 
1241 static void fd_writetrack( void )
1242 {
1243 	unsigned long paddr, flags;
1244 	unsigned int track;
1245 
1246 	DPRINT(("fd_writetrack() Tr=%d Si=%d\n", ReqTrack, ReqSide ));
1247 
1248 	paddr = PhysTrackBuffer;
1249 	dma_cache_maintenance( paddr, BUFFER_SIZE, 1 );
1250 
1251 	fd_select_side( ReqSide );
1252 
1253 	/* Cheat for track if stretch != 0 */
1254 	if (SUDT->stretch) {
1255 		track = FDC_READ( FDCREG_TRACK);
1256 		MFPDELAY();
1257 		FDC_WRITE(FDCREG_TRACK,track >> SUDT->stretch);
1258 	}
1259 	udelay(40);
1260 
1261 	/* Setup DMA */
1262 	local_irq_save(flags);
1263 	dma_wd.dma_lo = (unsigned char)paddr;
1264 	MFPDELAY();
1265 	paddr >>= 8;
1266 	dma_wd.dma_md = (unsigned char)paddr;
1267 	MFPDELAY();
1268 	paddr >>= 8;
1269 	if (ATARIHW_PRESENT( EXTD_DMA ))
1270 		st_dma_ext_dmahi = (unsigned short)paddr;
1271 	else
1272 		dma_wd.dma_hi = (unsigned char)paddr;
1273 	MFPDELAY();
1274 	local_irq_restore(flags);
1275 
1276 	/* Clear FIFO and switch DMA to correct mode */
1277 	dma_wd.dma_mode_status = 0x190;
1278 	MFPDELAY();
1279 	dma_wd.dma_mode_status = 0x90;
1280 	MFPDELAY();
1281 	dma_wd.dma_mode_status = 0x190;
1282 	MFPDELAY();
1283 
1284 	/* How many sectors for DMA */
1285 	dma_wd.fdc_acces_seccount = BUFFER_SIZE/512;
1286 	udelay(40);
1287 
1288 	/* Start operation */
1289 	dma_wd.dma_mode_status = FDCSELREG_STP | 0x100;
1290 	udelay(40);
1291 	SET_IRQ_HANDLER( fd_writetrack_done );
1292 	dma_wd.fdc_acces_seccount = FDCCMD_WRTRA | get_head_settle_flag();
1293 
1294 	MotorOn = 1;
1295 	start_timeout();
1296 	/* wait for interrupt */
1297 }
1298 
1299 
1300 static void fd_writetrack_done( int status )
1301 {
1302 	DPRINT(("fd_writetrack_done()\n"));
1303 
1304 	stop_timeout();
1305 
1306 	if (status & FDCSTAT_WPROT) {
1307 		printk(KERN_NOTICE "fd%d: is write protected\n", SelectedDrive );
1308 		goto err_end;
1309 	}
1310 	if (status & FDCSTAT_LOST) {
1311 		printk(KERN_ERR "fd%d: lost data (side %d, track %d)\n",
1312 				SelectedDrive, ReqSide, ReqTrack );
1313 		goto err_end;
1314 	}
1315 
1316 	complete(&format_wait);
1317 	return;
1318 
1319   err_end:
1320 	fd_error();
1321 }
1322 
1323 static void fd_times_out(struct timer_list *unused)
1324 {
1325 	atari_disable_irq( IRQ_MFP_FDC );
1326 	if (!FloppyIRQHandler) goto end; /* int occurred after timer was fired, but
1327 					  * before we came here... */
1328 
1329 	SET_IRQ_HANDLER( NULL );
1330 	/* If the timeout occurred while the readtrack_check timer was
1331 	 * active, we need to cancel it, else bad things will happen */
1332 	if (UseTrackbuffer)
1333 		del_timer( &readtrack_timer );
1334 	FDC_WRITE( FDCREG_CMD, FDCCMD_FORCI );
1335 	udelay( 25 );
1336 
1337 	printk(KERN_ERR "floppy timeout\n" );
1338 	fd_error();
1339   end:
1340 	atari_enable_irq( IRQ_MFP_FDC );
1341 }
1342 
1343 
1344 /* The (noop) seek operation here is needed to make the WP bit in the
1345  * FDC status register accessible for check_change. If the last disk
1346  * operation would have been a RDSEC, this bit would always read as 0
1347  * no matter what :-( To save time, the seek goes to the track we're
1348  * already on.
1349  */
1350 
1351 static void finish_fdc( void )
1352 {
1353 	if (!NeedSeek) {
1354 		finish_fdc_done( 0 );
1355 	}
1356 	else {
1357 		DPRINT(("finish_fdc: dummy seek started\n"));
1358 		FDC_WRITE (FDCREG_DATA, SUD.track);
1359 		SET_IRQ_HANDLER( finish_fdc_done );
1360 		FDC_WRITE (FDCREG_CMD, FDCCMD_SEEK);
1361 		MotorOn = 1;
1362 		start_timeout();
1363 		/* we must wait for the IRQ here, because the ST-DMA
1364 		   is released immediately afterwards and the interrupt
1365 		   may be delivered to the wrong driver. */
1366 	  }
1367 }
1368 
1369 
1370 static void finish_fdc_done( int dummy )
1371 {
1372 	unsigned long flags;
1373 
1374 	DPRINT(("finish_fdc_done entered\n"));
1375 	stop_timeout();
1376 	NeedSeek = 0;
1377 
1378 	if (timer_pending(&fd_timer) && time_before(fd_timer.expires, jiffies + 5))
1379 		/* If the check for a disk change is done too early after this
1380 		 * last seek command, the WP bit still reads wrong :-((
1381 		 */
1382 		mod_timer(&fd_timer, jiffies + 5);
1383 	else
1384 		start_check_change_timer();
1385 	start_motor_off_timer();
1386 
1387 	local_irq_save(flags);
1388 	stdma_release();
1389 	local_irq_restore(flags);
1390 
1391 	DPRINT(("finish_fdc() finished\n"));
1392 }
1393 
1394 /* The detection of disk changes is a dark chapter in Atari history :-(
1395  * Because the "Drive ready" signal isn't present in the Atari
1396  * hardware, one has to rely on the "Write Protect". This works fine,
1397  * as long as no write protected disks are used. TOS solves this
1398  * problem by introducing tri-state logic ("maybe changed") and
1399  * looking at the serial number in block 0. This isn't possible for
1400  * Linux, since the floppy driver can't make assumptions about the
1401  * filesystem used on the disk and thus the contents of block 0. I've
1402  * chosen the method to always say "The disk was changed" if it is
1403  * unsure whether it was. This implies that every open or mount
1404  * invalidates the disk buffers if you work with write protected
1405  * disks. But at least this is better than working with incorrect data
1406  * due to unrecognised disk changes.
1407  */
1408 
1409 static unsigned int floppy_check_events(struct gendisk *disk,
1410 					unsigned int clearing)
1411 {
1412 	struct atari_floppy_struct *p = disk->private_data;
1413 	unsigned int drive = p - unit;
1414 	if (test_bit (drive, &fake_change)) {
1415 		/* simulated change (e.g. after formatting) */
1416 		return DISK_EVENT_MEDIA_CHANGE;
1417 	}
1418 	if (test_bit (drive, &changed_floppies)) {
1419 		/* surely changed (the WP signal changed at least once) */
1420 		return DISK_EVENT_MEDIA_CHANGE;
1421 	}
1422 	if (UD.wpstat) {
1423 		/* WP is on -> could be changed: to be sure, buffers should be
1424 		 * invalidated...
1425 		 */
1426 		return DISK_EVENT_MEDIA_CHANGE;
1427 	}
1428 
1429 	return 0;
1430 }
1431 
1432 static int floppy_revalidate(struct gendisk *disk)
1433 {
1434 	struct atari_floppy_struct *p = disk->private_data;
1435 	unsigned int drive = p - unit;
1436 
1437 	if (test_bit(drive, &changed_floppies) ||
1438 	    test_bit(drive, &fake_change) ||
1439 	    p->disktype == 0) {
1440 		if (UD.flags & FTD_MSG)
1441 			printk(KERN_ERR "floppy: clear format %p!\n", UDT);
1442 		BufferDrive = -1;
1443 		clear_bit(drive, &fake_change);
1444 		clear_bit(drive, &changed_floppies);
1445 		/* MSch: clearing geometry makes sense only for autoprobe
1446 		   formats, for 'permanent user-defined' parameter:
1447 		   restore default_params[] here if flagged valid! */
1448 		if (default_params[drive].blocks == 0)
1449 			UDT = NULL;
1450 		else
1451 			UDT = &default_params[drive];
1452 	}
1453 	return 0;
1454 }
1455 
1456 
1457 /* This sets up the global variables describing the current request. */
1458 
1459 static void setup_req_params( int drive )
1460 {
1461 	int block = ReqBlock + ReqCnt;
1462 
1463 	ReqTrack = block / UDT->spt;
1464 	ReqSector = block - ReqTrack * UDT->spt + 1;
1465 	ReqSide = ReqTrack & 1;
1466 	ReqTrack >>= 1;
1467 	ReqData = ReqBuffer + 512 * ReqCnt;
1468 
1469 	if (UseTrackbuffer)
1470 		read_track = (ReqCmd == READ && fd_request->error_count == 0);
1471 	else
1472 		read_track = 0;
1473 
1474 	DPRINT(("Request params: Si=%d Tr=%d Se=%d Data=%08lx\n",ReqSide,
1475 			ReqTrack, ReqSector, (unsigned long)ReqData ));
1476 }
1477 
1478 static void ataflop_commit_rqs(struct blk_mq_hw_ctx *hctx)
1479 {
1480 	spin_lock_irq(&ataflop_lock);
1481 	atari_disable_irq(IRQ_MFP_FDC);
1482 	finish_fdc();
1483 	atari_enable_irq(IRQ_MFP_FDC);
1484 	spin_unlock_irq(&ataflop_lock);
1485 }
1486 
1487 static blk_status_t ataflop_queue_rq(struct blk_mq_hw_ctx *hctx,
1488 				     const struct blk_mq_queue_data *bd)
1489 {
1490 	struct atari_floppy_struct *floppy = bd->rq->rq_disk->private_data;
1491 	int drive = floppy - unit;
1492 	int type = floppy->type;
1493 
1494 	spin_lock_irq(&ataflop_lock);
1495 	if (fd_request) {
1496 		spin_unlock_irq(&ataflop_lock);
1497 		return BLK_STS_DEV_RESOURCE;
1498 	}
1499 	if (!stdma_try_lock(floppy_irq, NULL))  {
1500 		spin_unlock_irq(&ataflop_lock);
1501 		return BLK_STS_RESOURCE;
1502 	}
1503 	fd_request = bd->rq;
1504 	blk_mq_start_request(fd_request);
1505 
1506 	atari_disable_irq( IRQ_MFP_FDC );
1507 
1508 	IsFormatting = 0;
1509 
1510 	if (!UD.connected) {
1511 		/* drive not connected */
1512 		printk(KERN_ERR "Unknown Device: fd%d\n", drive );
1513 		fd_end_request_cur(BLK_STS_IOERR);
1514 		goto out;
1515 	}
1516 
1517 	if (type == 0) {
1518 		if (!UDT) {
1519 			Probing = 1;
1520 			UDT = atari_disk_type + StartDiskType[DriveType];
1521 			set_capacity(bd->rq->rq_disk, UDT->blocks);
1522 			UD.autoprobe = 1;
1523 		}
1524 	}
1525 	else {
1526 		/* user supplied disk type */
1527 		if (--type >= NUM_DISK_MINORS) {
1528 			printk(KERN_WARNING "fd%d: invalid disk format", drive );
1529 			fd_end_request_cur(BLK_STS_IOERR);
1530 			goto out;
1531 		}
1532 		if (minor2disktype[type].drive_types > DriveType)  {
1533 			printk(KERN_WARNING "fd%d: unsupported disk format", drive );
1534 			fd_end_request_cur(BLK_STS_IOERR);
1535 			goto out;
1536 		}
1537 		type = minor2disktype[type].index;
1538 		UDT = &atari_disk_type[type];
1539 		set_capacity(bd->rq->rq_disk, UDT->blocks);
1540 		UD.autoprobe = 0;
1541 	}
1542 
1543 	/* stop deselect timer */
1544 	del_timer( &motor_off_timer );
1545 
1546 	ReqCnt = 0;
1547 	ReqCmd = rq_data_dir(fd_request);
1548 	ReqBlock = blk_rq_pos(fd_request);
1549 	ReqBuffer = bio_data(fd_request->bio);
1550 	setup_req_params( drive );
1551 	do_fd_action( drive );
1552 
1553 	if (bd->last)
1554 		finish_fdc();
1555 	atari_enable_irq( IRQ_MFP_FDC );
1556 
1557 out:
1558 	spin_unlock_irq(&ataflop_lock);
1559 	return BLK_STS_OK;
1560 }
1561 
1562 static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
1563 		    unsigned int cmd, unsigned long param)
1564 {
1565 	struct gendisk *disk = bdev->bd_disk;
1566 	struct atari_floppy_struct *floppy = disk->private_data;
1567 	int drive = floppy - unit;
1568 	int type = floppy->type;
1569 	struct atari_format_descr fmt_desc;
1570 	struct atari_disk_type *dtp;
1571 	struct floppy_struct getprm;
1572 	int settype;
1573 	struct floppy_struct setprm;
1574 	void __user *argp = (void __user *)param;
1575 
1576 	switch (cmd) {
1577 	case FDGETPRM:
1578 		if (type) {
1579 			if (--type >= NUM_DISK_MINORS)
1580 				return -ENODEV;
1581 			if (minor2disktype[type].drive_types > DriveType)
1582 				return -ENODEV;
1583 			type = minor2disktype[type].index;
1584 			dtp = &atari_disk_type[type];
1585 			if (UD.flags & FTD_MSG)
1586 			    printk (KERN_ERR "floppy%d: found dtp %p name %s!\n",
1587 			        drive, dtp, dtp->name);
1588 		}
1589 		else {
1590 			if (!UDT)
1591 				return -ENXIO;
1592 			else
1593 				dtp = UDT;
1594 		}
1595 		memset((void *)&getprm, 0, sizeof(getprm));
1596 		getprm.size = dtp->blocks;
1597 		getprm.sect = dtp->spt;
1598 		getprm.head = 2;
1599 		getprm.track = dtp->blocks/dtp->spt/2;
1600 		getprm.stretch = dtp->stretch;
1601 		if (copy_to_user(argp, &getprm, sizeof(getprm)))
1602 			return -EFAULT;
1603 		return 0;
1604 	}
1605 	switch (cmd) {
1606 	case FDSETPRM:
1607 	case FDDEFPRM:
1608 	        /*
1609 		 * MSch 7/96: simple 'set geometry' case: just set the
1610 		 * 'default' device params (minor == 0).
1611 		 * Currently, the drive geometry is cleared after each
1612 		 * disk change and subsequent revalidate()! simple
1613 		 * implementation of FDDEFPRM: save geometry from a
1614 		 * FDDEFPRM call and restore it in floppy_revalidate() !
1615 		 */
1616 
1617 		/* get the parameters from user space */
1618 		if (floppy->ref != 1 && floppy->ref != -1)
1619 			return -EBUSY;
1620 		if (copy_from_user(&setprm, argp, sizeof(setprm)))
1621 			return -EFAULT;
1622 		/*
1623 		 * first of all: check for floppy change and revalidate,
1624 		 * or the next access will revalidate - and clear UDT :-(
1625 		 */
1626 
1627 		if (floppy_check_events(disk, 0))
1628 		        floppy_revalidate(disk);
1629 
1630 		if (UD.flags & FTD_MSG)
1631 		    printk (KERN_INFO "floppy%d: setting size %d spt %d str %d!\n",
1632 			drive, setprm.size, setprm.sect, setprm.stretch);
1633 
1634 		/* what if type > 0 here? Overwrite specified entry ? */
1635 		if (type) {
1636 		        /* refuse to re-set a predefined type for now */
1637 			return -EINVAL;
1638 		}
1639 
1640 		/*
1641 		 * type == 0: first look for a matching entry in the type list,
1642 		 * and set the UD.disktype field to use the perdefined entry.
1643 		 * TODO: add user-defined format to head of autoprobe list ?
1644 		 * Useful to include the user-type for future autodetection!
1645 		 */
1646 
1647 		for (settype = 0; settype < NUM_DISK_MINORS; settype++) {
1648 			int setidx = 0;
1649 			if (minor2disktype[settype].drive_types > DriveType) {
1650 				/* skip this one, invalid for drive ... */
1651 				continue;
1652 			}
1653 			setidx = minor2disktype[settype].index;
1654 			dtp = &atari_disk_type[setidx];
1655 
1656 			/* found matching entry ?? */
1657 			if (   dtp->blocks  == setprm.size
1658 			    && dtp->spt     == setprm.sect
1659 			    && dtp->stretch == setprm.stretch ) {
1660 				if (UD.flags & FTD_MSG)
1661 				    printk (KERN_INFO "floppy%d: setting %s %p!\n",
1662 				        drive, dtp->name, dtp);
1663 				UDT = dtp;
1664 				set_capacity(disk, UDT->blocks);
1665 
1666 				if (cmd == FDDEFPRM) {
1667 				  /* save settings as permanent default type */
1668 				  default_params[drive].name    = dtp->name;
1669 				  default_params[drive].spt     = dtp->spt;
1670 				  default_params[drive].blocks  = dtp->blocks;
1671 				  default_params[drive].fdc_speed = dtp->fdc_speed;
1672 				  default_params[drive].stretch = dtp->stretch;
1673 				}
1674 
1675 				return 0;
1676 			}
1677 
1678 		}
1679 
1680 		/* no matching disk type found above - setting user_params */
1681 
1682 	       	if (cmd == FDDEFPRM) {
1683 			/* set permanent type */
1684 			dtp = &default_params[drive];
1685 		} else
1686 			/* set user type (reset by disk change!) */
1687 			dtp = &user_params[drive];
1688 
1689 		dtp->name   = "user format";
1690 		dtp->blocks = setprm.size;
1691 		dtp->spt    = setprm.sect;
1692 		if (setprm.sect > 14)
1693 			dtp->fdc_speed = 3;
1694 		else
1695 			dtp->fdc_speed = 0;
1696 		dtp->stretch = setprm.stretch;
1697 
1698 		if (UD.flags & FTD_MSG)
1699 			printk (KERN_INFO "floppy%d: blk %d spt %d str %d!\n",
1700 				drive, dtp->blocks, dtp->spt, dtp->stretch);
1701 
1702 		/* sanity check */
1703 		if (setprm.track != dtp->blocks/dtp->spt/2 ||
1704 		    setprm.head != 2)
1705 			return -EINVAL;
1706 
1707 		UDT = dtp;
1708 		set_capacity(disk, UDT->blocks);
1709 
1710 		return 0;
1711 	case FDMSGON:
1712 		UD.flags |= FTD_MSG;
1713 		return 0;
1714 	case FDMSGOFF:
1715 		UD.flags &= ~FTD_MSG;
1716 		return 0;
1717 	case FDSETEMSGTRESH:
1718 		return -EINVAL;
1719 	case FDFMTBEG:
1720 		return 0;
1721 	case FDFMTTRK:
1722 		if (floppy->ref != 1 && floppy->ref != -1)
1723 			return -EBUSY;
1724 		if (copy_from_user(&fmt_desc, argp, sizeof(fmt_desc)))
1725 			return -EFAULT;
1726 		return do_format(drive, type, &fmt_desc);
1727 	case FDCLRPRM:
1728 		UDT = NULL;
1729 		/* MSch: invalidate default_params */
1730 		default_params[drive].blocks  = 0;
1731 		set_capacity(disk, MAX_DISK_SIZE * 2);
1732 		fallthrough;
1733 	case FDFMTEND:
1734 	case FDFLUSH:
1735 		/* invalidate the buffer track to force a reread */
1736 		BufferDrive = -1;
1737 		set_bit(drive, &fake_change);
1738 		if (bdev_check_media_change(bdev))
1739 			floppy_revalidate(bdev->bd_disk);
1740 		return 0;
1741 	default:
1742 		return -EINVAL;
1743 	}
1744 }
1745 
1746 static int fd_ioctl(struct block_device *bdev, fmode_t mode,
1747 			     unsigned int cmd, unsigned long arg)
1748 {
1749 	int ret;
1750 
1751 	mutex_lock(&ataflop_mutex);
1752 	ret = fd_locked_ioctl(bdev, mode, cmd, arg);
1753 	mutex_unlock(&ataflop_mutex);
1754 
1755 	return ret;
1756 }
1757 
1758 /* Initialize the 'unit' variable for drive 'drive' */
1759 
1760 static void __init fd_probe( int drive )
1761 {
1762 	UD.connected = 0;
1763 	UDT  = NULL;
1764 
1765 	if (!fd_test_drive_present( drive ))
1766 		return;
1767 
1768 	UD.connected = 1;
1769 	UD.track     = 0;
1770 	switch( UserSteprate[drive] ) {
1771 	case 2:
1772 		UD.steprate = FDCSTEP_2;
1773 		break;
1774 	case 3:
1775 		UD.steprate = FDCSTEP_3;
1776 		break;
1777 	case 6:
1778 		UD.steprate = FDCSTEP_6;
1779 		break;
1780 	case 12:
1781 		UD.steprate = FDCSTEP_12;
1782 		break;
1783 	default: /* should be -1 for "not set by user" */
1784 		if (ATARIHW_PRESENT( FDCSPEED ) || MACH_IS_MEDUSA)
1785 			UD.steprate = FDCSTEP_3;
1786 		else
1787 			UD.steprate = FDCSTEP_6;
1788 		break;
1789 	}
1790 	MotorOn = 1;	/* from probe restore operation! */
1791 }
1792 
1793 
1794 /* This function tests the physical presence of a floppy drive (not
1795  * whether a disk is inserted). This is done by issuing a restore
1796  * command, waiting max. 2 seconds (that should be enough to move the
1797  * head across the whole disk) and looking at the state of the "TR00"
1798  * signal. This should now be raised if there is a drive connected
1799  * (and there is no hardware failure :-) Otherwise, the drive is
1800  * declared absent.
1801  */
1802 
1803 static int __init fd_test_drive_present( int drive )
1804 {
1805 	unsigned long timeout;
1806 	unsigned char status;
1807 	int ok;
1808 
1809 	if (drive >= (MACH_IS_FALCON ? 1 : 2)) return( 0 );
1810 	fd_select_drive( drive );
1811 
1812 	/* disable interrupt temporarily */
1813 	atari_turnoff_irq( IRQ_MFP_FDC );
1814 	FDC_WRITE (FDCREG_TRACK, 0xff00);
1815 	FDC_WRITE( FDCREG_CMD, FDCCMD_RESTORE | FDCCMDADD_H | FDCSTEP_6 );
1816 
1817 	timeout = jiffies + 2*HZ+HZ/2;
1818 	while (time_before(jiffies, timeout))
1819 		if (!(st_mfp.par_dt_reg & 0x20))
1820 			break;
1821 
1822 	status = FDC_READ( FDCREG_STATUS );
1823 	ok = (status & FDCSTAT_TR00) != 0;
1824 
1825 	/* force interrupt to abort restore operation (FDC would try
1826 	 * about 50 seconds!) */
1827 	FDC_WRITE( FDCREG_CMD, FDCCMD_FORCI );
1828 	udelay(500);
1829 	status = FDC_READ( FDCREG_STATUS );
1830 	udelay(20);
1831 
1832 	if (ok) {
1833 		/* dummy seek command to make WP bit accessible */
1834 		FDC_WRITE( FDCREG_DATA, 0 );
1835 		FDC_WRITE( FDCREG_CMD, FDCCMD_SEEK );
1836 		while( st_mfp.par_dt_reg & 0x20 )
1837 			;
1838 		status = FDC_READ( FDCREG_STATUS );
1839 	}
1840 
1841 	atari_turnon_irq( IRQ_MFP_FDC );
1842 	return( ok );
1843 }
1844 
1845 
1846 /* Look how many and which kind of drives are connected. If there are
1847  * floppies, additionally start the disk-change and motor-off timers.
1848  */
1849 
1850 static void __init config_types( void )
1851 {
1852 	int drive, cnt = 0;
1853 
1854 	/* for probing drives, set the FDC speed to 8 MHz */
1855 	if (ATARIHW_PRESENT(FDCSPEED))
1856 		dma_wd.fdc_speed = 0;
1857 
1858 	printk(KERN_INFO "Probing floppy drive(s):\n");
1859 	for( drive = 0; drive < FD_MAX_UNITS; drive++ ) {
1860 		fd_probe( drive );
1861 		if (UD.connected) {
1862 			printk(KERN_INFO "fd%d\n", drive);
1863 			++cnt;
1864 		}
1865 	}
1866 
1867 	if (FDC_READ( FDCREG_STATUS ) & FDCSTAT_BUSY) {
1868 		/* If FDC is still busy from probing, give it another FORCI
1869 		 * command to abort the operation. If this isn't done, the FDC
1870 		 * will interrupt later and its IRQ line stays low, because
1871 		 * the status register isn't read. And this will block any
1872 		 * interrupts on this IRQ line :-(
1873 		 */
1874 		FDC_WRITE( FDCREG_CMD, FDCCMD_FORCI );
1875 		udelay(500);
1876 		FDC_READ( FDCREG_STATUS );
1877 		udelay(20);
1878 	}
1879 
1880 	if (cnt > 0) {
1881 		start_motor_off_timer();
1882 		if (cnt == 1) fd_select_drive( 0 );
1883 		start_check_change_timer();
1884 	}
1885 }
1886 
1887 /*
1888  * floppy_open check for aliasing (/dev/fd0 can be the same as
1889  * /dev/PS0 etc), and disallows simultaneous access to the same
1890  * drive with different device numbers.
1891  */
1892 
1893 static int floppy_open(struct block_device *bdev, fmode_t mode)
1894 {
1895 	struct atari_floppy_struct *p = bdev->bd_disk->private_data;
1896 	int type  = MINOR(bdev->bd_dev) >> 2;
1897 
1898 	DPRINT(("fd_open: type=%d\n",type));
1899 	if (p->ref && p->type != type)
1900 		return -EBUSY;
1901 
1902 	if (p->ref == -1 || (p->ref && mode & FMODE_EXCL))
1903 		return -EBUSY;
1904 
1905 	if (mode & FMODE_EXCL)
1906 		p->ref = -1;
1907 	else
1908 		p->ref++;
1909 
1910 	p->type = type;
1911 
1912 	if (mode & FMODE_NDELAY)
1913 		return 0;
1914 
1915 	if (mode & (FMODE_READ|FMODE_WRITE)) {
1916 		if (bdev_check_media_change(bdev))
1917 			floppy_revalidate(bdev->bd_disk);
1918 		if (mode & FMODE_WRITE) {
1919 			if (p->wpstat) {
1920 				if (p->ref < 0)
1921 					p->ref = 0;
1922 				else
1923 					p->ref--;
1924 				return -EROFS;
1925 			}
1926 		}
1927 	}
1928 	return 0;
1929 }
1930 
1931 static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
1932 {
1933 	int ret;
1934 
1935 	mutex_lock(&ataflop_mutex);
1936 	ret = floppy_open(bdev, mode);
1937 	mutex_unlock(&ataflop_mutex);
1938 
1939 	return ret;
1940 }
1941 
1942 static void floppy_release(struct gendisk *disk, fmode_t mode)
1943 {
1944 	struct atari_floppy_struct *p = disk->private_data;
1945 	mutex_lock(&ataflop_mutex);
1946 	if (p->ref < 0)
1947 		p->ref = 0;
1948 	else if (!p->ref--) {
1949 		printk(KERN_ERR "floppy_release with fd_ref == 0");
1950 		p->ref = 0;
1951 	}
1952 	mutex_unlock(&ataflop_mutex);
1953 }
1954 
1955 static const struct block_device_operations floppy_fops = {
1956 	.owner		= THIS_MODULE,
1957 	.open		= floppy_unlocked_open,
1958 	.release	= floppy_release,
1959 	.ioctl		= fd_ioctl,
1960 	.check_events	= floppy_check_events,
1961 };
1962 
1963 static const struct blk_mq_ops ataflop_mq_ops = {
1964 	.queue_rq = ataflop_queue_rq,
1965 	.commit_rqs = ataflop_commit_rqs,
1966 };
1967 
1968 static int ataflop_alloc_disk(unsigned int drive, unsigned int type)
1969 {
1970 	struct gendisk *disk;
1971 	int ret;
1972 
1973 	disk = alloc_disk(1);
1974 	if (!disk)
1975 		return -ENOMEM;
1976 
1977 	disk->queue = blk_mq_init_queue(&unit[drive].tag_set);
1978 	if (IS_ERR(disk->queue)) {
1979 		ret = PTR_ERR(disk->queue);
1980 		disk->queue = NULL;
1981 		put_disk(disk);
1982 		return ret;
1983 	}
1984 
1985 	disk->major = FLOPPY_MAJOR;
1986 	disk->first_minor = drive + (type << 2);
1987 	sprintf(disk->disk_name, "fd%d", drive);
1988 	disk->fops = &floppy_fops;
1989 	disk->events = DISK_EVENT_MEDIA_CHANGE;
1990 	disk->private_data = &unit[drive];
1991 	set_capacity(disk, MAX_DISK_SIZE * 2);
1992 
1993 	unit[drive].disk[type] = disk;
1994 	return 0;
1995 }
1996 
1997 static DEFINE_MUTEX(ataflop_probe_lock);
1998 
1999 static void ataflop_probe(dev_t dev)
2000 {
2001 	int drive = MINOR(dev) & 3;
2002 	int type  = MINOR(dev) >> 2;
2003 
2004 	if (type)
2005 		type--;
2006 
2007 	if (drive >= FD_MAX_UNITS || type >= NUM_DISK_MINORS)
2008 		return;
2009 	mutex_lock(&ataflop_probe_lock);
2010 	if (!unit[drive].disk[type]) {
2011 		if (ataflop_alloc_disk(drive, type) == 0)
2012 			add_disk(unit[drive].disk[type]);
2013 	}
2014 	mutex_unlock(&ataflop_probe_lock);
2015 }
2016 
2017 static int __init atari_floppy_init (void)
2018 {
2019 	int i;
2020 	int ret;
2021 
2022 	if (!MACH_IS_ATARI)
2023 		/* Amiga, Mac, ... don't have Atari-compatible floppy :-) */
2024 		return -ENODEV;
2025 
2026 	mutex_lock(&ataflop_probe_lock);
2027 	ret = __register_blkdev(FLOPPY_MAJOR, "fd", ataflop_probe);
2028 	if (ret)
2029 		goto out_unlock;
2030 
2031 	for (i = 0; i < FD_MAX_UNITS; i++) {
2032 		memset(&unit[i].tag_set, 0, sizeof(unit[i].tag_set));
2033 		unit[i].tag_set.ops = &ataflop_mq_ops;
2034 		unit[i].tag_set.nr_hw_queues = 1;
2035 		unit[i].tag_set.nr_maps = 1;
2036 		unit[i].tag_set.queue_depth = 2;
2037 		unit[i].tag_set.numa_node = NUMA_NO_NODE;
2038 		unit[i].tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
2039 		ret = blk_mq_alloc_tag_set(&unit[i].tag_set);
2040 		if (ret)
2041 			goto err;
2042 
2043 		ret = ataflop_alloc_disk(i, 0);
2044 		if (ret) {
2045 			blk_mq_free_tag_set(&unit[i].tag_set);
2046 			goto err;
2047 		}
2048 	}
2049 
2050 	if (UseTrackbuffer < 0)
2051 		/* not set by user -> use default: for now, we turn
2052 		   track buffering off for all Medusas, though it
2053 		   could be used with ones that have a counter
2054 		   card. But the test is too hard :-( */
2055 		UseTrackbuffer = !MACH_IS_MEDUSA;
2056 
2057 	/* initialize variables */
2058 	SelectedDrive = -1;
2059 	BufferDrive = -1;
2060 
2061 	DMABuffer = atari_stram_alloc(BUFFER_SIZE+512, "ataflop");
2062 	if (!DMABuffer) {
2063 		printk(KERN_ERR "atari_floppy_init: cannot get dma buffer\n");
2064 		ret = -ENOMEM;
2065 		goto err;
2066 	}
2067 	TrackBuffer = DMABuffer + 512;
2068 	PhysDMABuffer = atari_stram_to_phys(DMABuffer);
2069 	PhysTrackBuffer = virt_to_phys(TrackBuffer);
2070 	BufferDrive = BufferSide = BufferTrack = -1;
2071 
2072 	for (i = 0; i < FD_MAX_UNITS; i++) {
2073 		unit[i].track = -1;
2074 		unit[i].flags = 0;
2075 		add_disk(unit[i].disk[0]);
2076 	}
2077 
2078 	printk(KERN_INFO "Atari floppy driver: max. %cD, %strack buffering\n",
2079 	       DriveType == 0 ? 'D' : DriveType == 1 ? 'H' : 'E',
2080 	       UseTrackbuffer ? "" : "no ");
2081 	config_types();
2082 
2083 	return 0;
2084 
2085 err:
2086 	while (--i >= 0) {
2087 		blk_cleanup_queue(unit[i].disk[0]->queue);
2088 		put_disk(unit[i].disk[0]);
2089 		blk_mq_free_tag_set(&unit[i].tag_set);
2090 	}
2091 
2092 	unregister_blkdev(FLOPPY_MAJOR, "fd");
2093 out_unlock:
2094 	mutex_unlock(&ataflop_probe_lock);
2095 	return ret;
2096 }
2097 
2098 #ifndef MODULE
2099 static int __init atari_floppy_setup(char *str)
2100 {
2101 	int ints[3 + FD_MAX_UNITS];
2102 	int i;
2103 
2104 	if (!MACH_IS_ATARI)
2105 		return 0;
2106 
2107 	str = get_options(str, 3 + FD_MAX_UNITS, ints);
2108 
2109 	if (ints[0] < 1) {
2110 		printk(KERN_ERR "ataflop_setup: no arguments!\n" );
2111 		return 0;
2112 	}
2113 	else if (ints[0] > 2+FD_MAX_UNITS) {
2114 		printk(KERN_ERR "ataflop_setup: too many arguments\n" );
2115 	}
2116 
2117 	if (ints[1] < 0 || ints[1] > 2)
2118 		printk(KERN_ERR "ataflop_setup: bad drive type\n" );
2119 	else
2120 		DriveType = ints[1];
2121 
2122 	if (ints[0] >= 2)
2123 		UseTrackbuffer = (ints[2] > 0);
2124 
2125 	for( i = 3; i <= ints[0] && i-3 < FD_MAX_UNITS; ++i ) {
2126 		if (ints[i] != 2 && ints[i] != 3 && ints[i] != 6 && ints[i] != 12)
2127 			printk(KERN_ERR "ataflop_setup: bad steprate\n" );
2128 		else
2129 			UserSteprate[i-3] = ints[i];
2130 	}
2131 	return 1;
2132 }
2133 
2134 __setup("floppy=", atari_floppy_setup);
2135 #endif
2136 
2137 static void __exit atari_floppy_exit(void)
2138 {
2139 	int i, type;
2140 
2141 	for (i = 0; i < FD_MAX_UNITS; i++) {
2142 		for (type = 0; type < NUM_DISK_MINORS; type++) {
2143 			if (!unit[i].disk[type])
2144 				continue;
2145 			del_gendisk(unit[i].disk[type]);
2146 			blk_cleanup_queue(unit[i].disk[type]->queue);
2147 			put_disk(unit[i].disk[type]);
2148 		}
2149 		blk_mq_free_tag_set(&unit[i].tag_set);
2150 	}
2151 	unregister_blkdev(FLOPPY_MAJOR, "fd");
2152 
2153 	del_timer_sync(&fd_timer);
2154 	atari_stram_free( DMABuffer );
2155 }
2156 
2157 module_init(atari_floppy_init)
2158 module_exit(atari_floppy_exit)
2159 
2160 MODULE_LICENSE("GPL");
2161