4 * Basic PIO and command management functionality.
6 * This code was split off from ide.c. See ide.c for history and original
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2, or (at your option) any
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * For the avoidance of doubt the "preferred form" of this code is one which
20 * is in an open non patent encumbered format. Where cryptographic key signing
21 * forms part of the process of creating an executable the information
22 * including keys needed to generate an equivalently functional executable
23 * are deemed to be part of the source code.
27 #include <linux/config.h>
28 #include <linux/module.h>
29 #include <linux/types.h>
30 #include <linux/string.h>
31 #include <linux/kernel.h>
32 #include <linux/timer.h>
34 #include <linux/interrupt.h>
35 #include <linux/major.h>
36 #include <linux/errno.h>
37 #include <linux/genhd.h>
38 #include <linux/blkpg.h>
39 #include <linux/slab.h>
40 #include <linux/init.h>
41 #include <linux/pci.h>
42 #include <linux/delay.h>
43 #include <linux/ide.h>
44 #include <linux/completion.h>
45 #include <linux/reboot.h>
46 #include <linux/cdrom.h>
47 #include <linux/seq_file.h>
48 #include <linux/device.h>
49 #include <linux/kmod.h>
50 #include <linux/scatterlist.h>
52 #include <asm/byteorder.h>
54 #include <asm/uaccess.h>
56 #include <asm/bitops.h>
58 void ide_softirq_done(struct request
*rq
)
60 request_queue_t
*q
= rq
->q
;
62 add_disk_randomness(rq
->rq_disk
);
63 end_that_request_chunk(rq
, rq
->errors
, rq
->data_len
);
65 spin_lock_irq(q
->queue_lock
);
66 end_that_request_last(rq
, rq
->errors
);
67 spin_unlock_irq(q
->queue_lock
);
70 int __ide_end_request(ide_drive_t
*drive
, struct request
*rq
, int uptodate
,
76 BUG_ON(!(rq
->flags
& REQ_STARTED
));
79 * if failfast is set on a request, override number of sectors and
80 * complete the whole request right now
82 if (blk_noretry_request(rq
) && end_io_error(uptodate
))
83 nr_sectors
= rq
->hard_nr_sectors
;
85 if (!blk_fs_request(rq
) && end_io_error(uptodate
) && !rq
->errors
)
89 * decide whether to reenable DMA -- 3 is a random magic for now,
90 * if we DMA timeout more than 3 times, just stay in PIO
92 if (drive
->state
== DMA_PIO_RETRY
&& drive
->retry_pio
<= 3) {
94 HWGROUP(drive
)->hwif
->ide_dma_on(drive
);
98 * For partial completions (or non fs/pc requests), use the regular
99 * direct completion path.
101 nbytes
= nr_sectors
<< 9;
102 if (rq_all_done(rq
, nbytes
)) {
103 rq
->errors
= uptodate
;
104 rq
->data_len
= nbytes
;
105 blkdev_dequeue_request(rq
);
106 HWGROUP(drive
)->rq
= NULL
;
107 blk_complete_request(rq
);
110 if (!end_that_request_first(rq
, uptodate
, nr_sectors
)) {
111 add_disk_randomness(rq
->rq_disk
);
112 blkdev_dequeue_request(rq
);
113 HWGROUP(drive
)->rq
= NULL
;
114 end_that_request_last(rq
, uptodate
);
121 EXPORT_SYMBOL(__ide_end_request
);
124 * ide_end_request - complete an IDE I/O
125 * @drive: IDE device for the I/O
127 * @nr_sectors: number of sectors completed
129 * This is our end_request wrapper function. We complete the I/O
130 * update random number input and dequeue the request, which if
131 * it was tagged may be out of order.
134 int ide_end_request (ide_drive_t
*drive
, int uptodate
, int nr_sectors
)
141 * room for locking improvements here, the calls below don't
142 * need the queue lock held at all
144 spin_lock_irqsave(&ide_lock
, flags
);
145 rq
= HWGROUP(drive
)->rq
;
148 nr_sectors
= rq
->hard_cur_sectors
;
150 ret
= __ide_end_request(drive
, rq
, uptodate
, nr_sectors
);
152 spin_unlock_irqrestore(&ide_lock
, flags
);
155 EXPORT_SYMBOL(ide_end_request
);
158 * Power Management state machine. This one is rather trivial for now,
159 * we should probably add more, like switching back to PIO on suspend
160 * to help some BIOSes, re-do the door locking on resume, etc...
164 ide_pm_flush_cache
= ide_pm_state_start_suspend
,
167 idedisk_pm_idle
= ide_pm_state_start_resume
,
171 static void ide_complete_power_step(ide_drive_t
*drive
, struct request
*rq
, u8 stat
, u8 error
)
173 if (drive
->media
!= ide_disk
)
176 switch (rq
->pm
->pm_step
) {
177 case ide_pm_flush_cache
: /* Suspend step 1 (flush cache) complete */
178 if (rq
->pm
->pm_state
== PM_EVENT_FREEZE
)
179 rq
->pm
->pm_step
= ide_pm_state_completed
;
181 rq
->pm
->pm_step
= idedisk_pm_standby
;
183 case idedisk_pm_standby
: /* Suspend step 2 (standby) complete */
184 rq
->pm
->pm_step
= ide_pm_state_completed
;
186 case idedisk_pm_idle
: /* Resume step 1 (idle) complete */
187 rq
->pm
->pm_step
= ide_pm_restore_dma
;
192 static ide_startstop_t
ide_start_power_step(ide_drive_t
*drive
, struct request
*rq
)
194 ide_task_t
*args
= rq
->special
;
196 memset(args
, 0, sizeof(*args
));
198 if (drive
->media
!= ide_disk
) {
199 /* skip idedisk_pm_idle for ATAPI devices */
200 if (rq
->pm
->pm_step
== idedisk_pm_idle
)
201 rq
->pm
->pm_step
= ide_pm_restore_dma
;
204 switch (rq
->pm
->pm_step
) {
205 case ide_pm_flush_cache
: /* Suspend step 1 (flush cache) */
206 if (drive
->media
!= ide_disk
)
208 /* Not supported? Switch to next step now. */
209 if (!drive
->wcache
|| !ide_id_has_flush_cache(drive
->id
)) {
210 ide_complete_power_step(drive
, rq
, 0, 0);
213 if (ide_id_has_flush_cache_ext(drive
->id
))
214 args
->tfRegister
[IDE_COMMAND_OFFSET
] = WIN_FLUSH_CACHE_EXT
;
216 args
->tfRegister
[IDE_COMMAND_OFFSET
] = WIN_FLUSH_CACHE
;
217 args
->command_type
= IDE_DRIVE_TASK_NO_DATA
;
218 args
->handler
= &task_no_data_intr
;
219 return do_rw_taskfile(drive
, args
);
221 case idedisk_pm_standby
: /* Suspend step 2 (standby) */
222 args
->tfRegister
[IDE_COMMAND_OFFSET
] = WIN_STANDBYNOW1
;
223 args
->command_type
= IDE_DRIVE_TASK_NO_DATA
;
224 args
->handler
= &task_no_data_intr
;
225 return do_rw_taskfile(drive
, args
);
227 case idedisk_pm_idle
: /* Resume step 1 (idle) */
228 args
->tfRegister
[IDE_COMMAND_OFFSET
] = WIN_IDLEIMMEDIATE
;
229 args
->command_type
= IDE_DRIVE_TASK_NO_DATA
;
230 args
->handler
= task_no_data_intr
;
231 return do_rw_taskfile(drive
, args
);
233 case ide_pm_restore_dma
: /* Resume step 2 (restore DMA) */
235 * Right now, all we do is call hwif->ide_dma_check(drive),
236 * we could be smarter and check for current xfer_speed
237 * in struct drive etc...
239 if ((drive
->id
->capability
& 1) == 0)
241 if (drive
->hwif
->ide_dma_check
== NULL
)
243 drive
->hwif
->ide_dma_check(drive
);
246 rq
->pm
->pm_step
= ide_pm_state_completed
;
251 * ide_complete_pm_request - end the current Power Management request
252 * @drive: target drive
255 * This function cleans up the current PM request and stops the queue
258 static void ide_complete_pm_request (ide_drive_t
*drive
, struct request
*rq
)
263 printk("%s: completing PM request, %s\n", drive
->name
,
264 blk_pm_suspend_request(rq
) ? "suspend" : "resume");
266 spin_lock_irqsave(&ide_lock
, flags
);
267 if (blk_pm_suspend_request(rq
)) {
268 blk_stop_queue(drive
->queue
);
271 blk_start_queue(drive
->queue
);
273 blkdev_dequeue_request(rq
);
274 HWGROUP(drive
)->rq
= NULL
;
275 end_that_request_last(rq
, 1);
276 spin_unlock_irqrestore(&ide_lock
, flags
);
280 * FIXME: probably move this somewhere else, name is bad too :)
282 u64
ide_get_error_location(ide_drive_t
*drive
, char *args
)
293 if (ide_id_has_flush_cache_ext(drive
->id
)) {
294 low
= (hcyl
<< 16) | (lcyl
<< 8) | sect
;
295 HWIF(drive
)->OUTB(drive
->ctl
|0x80, IDE_CONTROL_REG
);
296 high
= ide_read_24(drive
);
298 u8 cur
= HWIF(drive
)->INB(IDE_SELECT_REG
);
301 low
= (hcyl
<< 16) | (lcyl
<< 8) | sect
;
303 low
= hcyl
* drive
->head
* drive
->sect
;
304 low
+= lcyl
* drive
->sect
;
309 sector
= ((u64
) high
<< 24) | low
;
312 EXPORT_SYMBOL(ide_get_error_location
);
315 * ide_end_drive_cmd - end an explicit drive command
320 * Clean up after success/failure of an explicit drive command.
321 * These get thrown onto the queue so they are synchronized with
322 * real I/O operations on the drive.
324 * In LBA48 mode we have to read the register set twice to get
325 * all the extra information out.
328 void ide_end_drive_cmd (ide_drive_t
*drive
, u8 stat
, u8 err
)
330 ide_hwif_t
*hwif
= HWIF(drive
);
334 spin_lock_irqsave(&ide_lock
, flags
);
335 rq
= HWGROUP(drive
)->rq
;
336 spin_unlock_irqrestore(&ide_lock
, flags
);
338 if (rq
->flags
& REQ_DRIVE_CMD
) {
339 u8
*args
= (u8
*) rq
->buffer
;
341 rq
->errors
= !OK_STAT(stat
,READY_STAT
,BAD_STAT
);
346 args
[2] = hwif
->INB(IDE_NSECTOR_REG
);
348 } else if (rq
->flags
& REQ_DRIVE_TASK
) {
349 u8
*args
= (u8
*) rq
->buffer
;
351 rq
->errors
= !OK_STAT(stat
,READY_STAT
,BAD_STAT
);
356 args
[2] = hwif
->INB(IDE_NSECTOR_REG
);
357 args
[3] = hwif
->INB(IDE_SECTOR_REG
);
358 args
[4] = hwif
->INB(IDE_LCYL_REG
);
359 args
[5] = hwif
->INB(IDE_HCYL_REG
);
360 args
[6] = hwif
->INB(IDE_SELECT_REG
);
362 } else if (rq
->flags
& REQ_DRIVE_TASKFILE
) {
363 ide_task_t
*args
= (ide_task_t
*) rq
->special
;
365 rq
->errors
= !OK_STAT(stat
,READY_STAT
,BAD_STAT
);
368 if (args
->tf_in_flags
.b
.data
) {
369 u16 data
= hwif
->INW(IDE_DATA_REG
);
370 args
->tfRegister
[IDE_DATA_OFFSET
] = (data
) & 0xFF;
371 args
->hobRegister
[IDE_DATA_OFFSET
] = (data
>> 8) & 0xFF;
373 args
->tfRegister
[IDE_ERROR_OFFSET
] = err
;
374 /* be sure we're looking at the low order bits */
375 hwif
->OUTB(drive
->ctl
& ~0x80, IDE_CONTROL_REG
);
376 args
->tfRegister
[IDE_NSECTOR_OFFSET
] = hwif
->INB(IDE_NSECTOR_REG
);
377 args
->tfRegister
[IDE_SECTOR_OFFSET
] = hwif
->INB(IDE_SECTOR_REG
);
378 args
->tfRegister
[IDE_LCYL_OFFSET
] = hwif
->INB(IDE_LCYL_REG
);
379 args
->tfRegister
[IDE_HCYL_OFFSET
] = hwif
->INB(IDE_HCYL_REG
);
380 args
->tfRegister
[IDE_SELECT_OFFSET
] = hwif
->INB(IDE_SELECT_REG
);
381 args
->tfRegister
[IDE_STATUS_OFFSET
] = stat
;
383 if (drive
->addressing
== 1) {
384 hwif
->OUTB(drive
->ctl
|0x80, IDE_CONTROL_REG
);
385 args
->hobRegister
[IDE_FEATURE_OFFSET
] = hwif
->INB(IDE_FEATURE_REG
);
386 args
->hobRegister
[IDE_NSECTOR_OFFSET
] = hwif
->INB(IDE_NSECTOR_REG
);
387 args
->hobRegister
[IDE_SECTOR_OFFSET
] = hwif
->INB(IDE_SECTOR_REG
);
388 args
->hobRegister
[IDE_LCYL_OFFSET
] = hwif
->INB(IDE_LCYL_REG
);
389 args
->hobRegister
[IDE_HCYL_OFFSET
] = hwif
->INB(IDE_HCYL_REG
);
392 } else if (blk_pm_request(rq
)) {
394 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
395 drive
->name
, rq
->pm
->pm_step
, stat
, err
);
397 ide_complete_power_step(drive
, rq
, stat
, err
);
398 if (rq
->pm
->pm_step
== ide_pm_state_completed
)
399 ide_complete_pm_request(drive
, rq
);
403 spin_lock_irqsave(&ide_lock
, flags
);
404 blkdev_dequeue_request(rq
);
405 HWGROUP(drive
)->rq
= NULL
;
407 end_that_request_last(rq
, !rq
->errors
);
408 spin_unlock_irqrestore(&ide_lock
, flags
);
411 EXPORT_SYMBOL(ide_end_drive_cmd
);
414 * try_to_flush_leftover_data - flush junk
415 * @drive: drive to flush
417 * try_to_flush_leftover_data() is invoked in response to a drive
418 * unexpectedly having its DRQ_STAT bit set. As an alternative to
419 * resetting the drive, this routine tries to clear the condition
420 * by read a sector's worth of data from the drive. Of course,
421 * this may not help if the drive is *waiting* for data from *us*.
423 static void try_to_flush_leftover_data (ide_drive_t
*drive
)
425 int i
= (drive
->mult_count
? drive
->mult_count
: 1) * SECTOR_WORDS
;
427 if (drive
->media
!= ide_disk
)
431 u32 wcount
= (i
> 16) ? 16 : i
;
434 HWIF(drive
)->ata_input_data(drive
, buffer
, wcount
);
438 static void ide_kill_rq(ide_drive_t
*drive
, struct request
*rq
)
443 drv
= *(ide_driver_t
**)rq
->rq_disk
->private_data
;
444 drv
->end_request(drive
, 0, 0);
446 ide_end_request(drive
, 0, 0);
449 static ide_startstop_t
ide_ata_error(ide_drive_t
*drive
, struct request
*rq
, u8 stat
, u8 err
)
451 ide_hwif_t
*hwif
= drive
->hwif
;
453 if (stat
& BUSY_STAT
|| ((stat
& WRERR_STAT
) && !drive
->nowerr
)) {
454 /* other bits are useless when BUSY */
455 rq
->errors
|= ERROR_RESET
;
456 } else if (stat
& ERR_STAT
) {
457 /* err has different meaning on cdrom and tape */
458 if (err
== ABRT_ERR
) {
459 if (drive
->select
.b
.lba
&&
460 /* some newer drives don't support WIN_SPECIFY */
461 hwif
->INB(IDE_COMMAND_REG
) == WIN_SPECIFY
)
463 } else if ((err
& BAD_CRC
) == BAD_CRC
) {
464 /* UDMA crc error, just retry the operation */
466 } else if (err
& (BBD_ERR
| ECC_ERR
)) {
467 /* retries won't help these */
468 rq
->errors
= ERROR_MAX
;
469 } else if (err
& TRK0_ERR
) {
470 /* help it find track zero */
471 rq
->errors
|= ERROR_RECAL
;
475 if ((stat
& DRQ_STAT
) && rq_data_dir(rq
) == READ
)
476 try_to_flush_leftover_data(drive
);
478 if (hwif
->INB(IDE_STATUS_REG
) & (BUSY_STAT
|DRQ_STAT
))
480 hwif
->OUTB(WIN_IDLEIMMEDIATE
, IDE_COMMAND_REG
);
482 if (rq
->errors
>= ERROR_MAX
|| blk_noretry_request(rq
))
483 ide_kill_rq(drive
, rq
);
485 if ((rq
->errors
& ERROR_RESET
) == ERROR_RESET
) {
487 return ide_do_reset(drive
);
489 if ((rq
->errors
& ERROR_RECAL
) == ERROR_RECAL
)
490 drive
->special
.b
.recalibrate
= 1;
496 static ide_startstop_t
ide_atapi_error(ide_drive_t
*drive
, struct request
*rq
, u8 stat
, u8 err
)
498 ide_hwif_t
*hwif
= drive
->hwif
;
500 if (stat
& BUSY_STAT
|| ((stat
& WRERR_STAT
) && !drive
->nowerr
)) {
501 /* other bits are useless when BUSY */
502 rq
->errors
|= ERROR_RESET
;
504 /* add decoding error stuff */
507 if (hwif
->INB(IDE_STATUS_REG
) & (BUSY_STAT
|DRQ_STAT
))
509 hwif
->OUTB(WIN_IDLEIMMEDIATE
, IDE_COMMAND_REG
);
511 if (rq
->errors
>= ERROR_MAX
) {
512 ide_kill_rq(drive
, rq
);
514 if ((rq
->errors
& ERROR_RESET
) == ERROR_RESET
) {
516 return ide_do_reset(drive
);
525 __ide_error(ide_drive_t
*drive
, struct request
*rq
, u8 stat
, u8 err
)
527 if (drive
->media
== ide_disk
)
528 return ide_ata_error(drive
, rq
, stat
, err
);
529 return ide_atapi_error(drive
, rq
, stat
, err
);
532 EXPORT_SYMBOL_GPL(__ide_error
);
535 * ide_error - handle an error on the IDE
536 * @drive: drive the error occurred on
537 * @msg: message to report
540 * ide_error() takes action based on the error returned by the drive.
541 * For normal I/O that may well include retries. We deal with
542 * both new-style (taskfile) and old style command handling here.
543 * In the case of taskfile command handling there is work left to
547 ide_startstop_t
ide_error (ide_drive_t
*drive
, const char *msg
, u8 stat
)
552 err
= ide_dump_status(drive
, msg
, stat
);
554 if ((rq
= HWGROUP(drive
)->rq
) == NULL
)
557 /* retry only "normal" I/O: */
558 if (rq
->flags
& (REQ_DRIVE_CMD
| REQ_DRIVE_TASK
| REQ_DRIVE_TASKFILE
)) {
560 ide_end_drive_cmd(drive
, stat
, err
);
567 drv
= *(ide_driver_t
**)rq
->rq_disk
->private_data
;
568 return drv
->error(drive
, rq
, stat
, err
);
570 return __ide_error(drive
, rq
, stat
, err
);
573 EXPORT_SYMBOL_GPL(ide_error
);
575 ide_startstop_t
__ide_abort(ide_drive_t
*drive
, struct request
*rq
)
577 if (drive
->media
!= ide_disk
)
578 rq
->errors
|= ERROR_RESET
;
580 ide_kill_rq(drive
, rq
);
585 EXPORT_SYMBOL_GPL(__ide_abort
);
588 * ide_abort - abort pending IDE operations
589 * @drive: drive the error occurred on
590 * @msg: message to report
592 * ide_abort kills and cleans up when we are about to do a
593 * host initiated reset on active commands. Longer term we
594 * want handlers to have sensible abort handling themselves
596 * This differs fundamentally from ide_error because in
597 * this case the command is doing just fine when we
601 ide_startstop_t
ide_abort(ide_drive_t
*drive
, const char *msg
)
605 if (drive
== NULL
|| (rq
= HWGROUP(drive
)->rq
) == NULL
)
608 /* retry only "normal" I/O: */
609 if (rq
->flags
& (REQ_DRIVE_CMD
| REQ_DRIVE_TASK
| REQ_DRIVE_TASKFILE
)) {
611 ide_end_drive_cmd(drive
, BUSY_STAT
, 0);
618 drv
= *(ide_driver_t
**)rq
->rq_disk
->private_data
;
619 return drv
->abort(drive
, rq
);
621 return __ide_abort(drive
, rq
);
625 * ide_cmd - issue a simple drive command
626 * @drive: drive the command is for
628 * @nsect: sector byte
629 * @handler: handler for the command completion
631 * Issue a simple drive command with interrupts.
632 * The drive must be selected beforehand.
635 static void ide_cmd (ide_drive_t
*drive
, u8 cmd
, u8 nsect
,
636 ide_handler_t
*handler
)
638 ide_hwif_t
*hwif
= HWIF(drive
);
640 hwif
->OUTB(drive
->ctl
,IDE_CONTROL_REG
); /* clear nIEN */
641 SELECT_MASK(drive
,0);
642 hwif
->OUTB(nsect
,IDE_NSECTOR_REG
);
643 ide_execute_command(drive
, cmd
, handler
, WAIT_CMD
, NULL
);
647 * drive_cmd_intr - drive command completion interrupt
648 * @drive: drive the completion interrupt occurred on
650 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
651 * We do any necessary data reading and then wait for the drive to
652 * go non busy. At that point we may read the error data and complete
656 static ide_startstop_t
drive_cmd_intr (ide_drive_t
*drive
)
658 struct request
*rq
= HWGROUP(drive
)->rq
;
659 ide_hwif_t
*hwif
= HWIF(drive
);
660 u8
*args
= (u8
*) rq
->buffer
;
661 u8 stat
= hwif
->INB(IDE_STATUS_REG
);
665 if ((stat
& DRQ_STAT
) && args
&& args
[3]) {
666 u8 io_32bit
= drive
->io_32bit
;
668 hwif
->ata_input_data(drive
, &args
[4], args
[3] * SECTOR_WORDS
);
669 drive
->io_32bit
= io_32bit
;
670 while (((stat
= hwif
->INB(IDE_STATUS_REG
)) & BUSY_STAT
) && retries
--)
674 if (!OK_STAT(stat
, READY_STAT
, BAD_STAT
))
675 return ide_error(drive
, "drive_cmd", stat
);
676 /* calls ide_end_drive_cmd */
677 ide_end_drive_cmd(drive
, stat
, hwif
->INB(IDE_ERROR_REG
));
681 static void ide_init_specify_cmd(ide_drive_t
*drive
, ide_task_t
*task
)
683 task
->tfRegister
[IDE_NSECTOR_OFFSET
] = drive
->sect
;
684 task
->tfRegister
[IDE_SECTOR_OFFSET
] = drive
->sect
;
685 task
->tfRegister
[IDE_LCYL_OFFSET
] = drive
->cyl
;
686 task
->tfRegister
[IDE_HCYL_OFFSET
] = drive
->cyl
>>8;
687 task
->tfRegister
[IDE_SELECT_OFFSET
] = ((drive
->head
-1)|drive
->select
.all
)&0xBF;
688 task
->tfRegister
[IDE_COMMAND_OFFSET
] = WIN_SPECIFY
;
690 task
->handler
= &set_geometry_intr
;
693 static void ide_init_restore_cmd(ide_drive_t
*drive
, ide_task_t
*task
)
695 task
->tfRegister
[IDE_NSECTOR_OFFSET
] = drive
->sect
;
696 task
->tfRegister
[IDE_COMMAND_OFFSET
] = WIN_RESTORE
;
698 task
->handler
= &recal_intr
;
701 static void ide_init_setmult_cmd(ide_drive_t
*drive
, ide_task_t
*task
)
703 task
->tfRegister
[IDE_NSECTOR_OFFSET
] = drive
->mult_req
;
704 task
->tfRegister
[IDE_COMMAND_OFFSET
] = WIN_SETMULT
;
706 task
->handler
= &set_multmode_intr
;
709 static ide_startstop_t
ide_disk_special(ide_drive_t
*drive
)
711 special_t
*s
= &drive
->special
;
714 memset(&args
, 0, sizeof(ide_task_t
));
715 args
.command_type
= IDE_DRIVE_TASK_NO_DATA
;
717 if (s
->b
.set_geometry
) {
718 s
->b
.set_geometry
= 0;
719 ide_init_specify_cmd(drive
, &args
);
720 } else if (s
->b
.recalibrate
) {
721 s
->b
.recalibrate
= 0;
722 ide_init_restore_cmd(drive
, &args
);
723 } else if (s
->b
.set_multmode
) {
724 s
->b
.set_multmode
= 0;
725 if (drive
->mult_req
> drive
->id
->max_multsect
)
726 drive
->mult_req
= drive
->id
->max_multsect
;
727 ide_init_setmult_cmd(drive
, &args
);
729 int special
= s
->all
;
731 printk(KERN_ERR
"%s: bad special flag: 0x%02x\n", drive
->name
, special
);
735 do_rw_taskfile(drive
, &args
);
741 * do_special - issue some special commands
742 * @drive: drive the command is for
744 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
745 * commands to a drive. It used to do much more, but has been scaled
749 static ide_startstop_t
do_special (ide_drive_t
*drive
)
751 special_t
*s
= &drive
->special
;
754 printk("%s: do_special: 0x%02x\n", drive
->name
, s
->all
);
758 if (HWIF(drive
)->tuneproc
!= NULL
)
759 HWIF(drive
)->tuneproc(drive
, drive
->tune_req
);
762 if (drive
->media
== ide_disk
)
763 return ide_disk_special(drive
);
771 void ide_map_sg(ide_drive_t
*drive
, struct request
*rq
)
773 ide_hwif_t
*hwif
= drive
->hwif
;
774 struct scatterlist
*sg
= hwif
->sg_table
;
776 if (hwif
->sg_mapped
) /* needed by ide-scsi */
779 if ((rq
->flags
& REQ_DRIVE_TASKFILE
) == 0) {
780 hwif
->sg_nents
= blk_rq_map_sg(drive
->queue
, rq
, sg
);
782 sg_init_one(sg
, rq
->buffer
, rq
->nr_sectors
* SECTOR_SIZE
);
787 EXPORT_SYMBOL_GPL(ide_map_sg
);
789 void ide_init_sg_cmd(ide_drive_t
*drive
, struct request
*rq
)
791 ide_hwif_t
*hwif
= drive
->hwif
;
793 hwif
->nsect
= hwif
->nleft
= rq
->nr_sectors
;
794 hwif
->cursg
= hwif
->cursg_ofs
= 0;
797 EXPORT_SYMBOL_GPL(ide_init_sg_cmd
);
800 * execute_drive_command - issue special drive command
801 * @drive: the drive to issue the command on
802 * @rq: the request structure holding the command
804 * execute_drive_cmd() issues a special drive command, usually
805 * initiated by ioctl() from the external hdparm program. The
806 * command can be a drive command, drive task or taskfile
807 * operation. Weirdly you can call it with NULL to wait for
808 * all commands to finish. Don't do this as that is due to change
811 static ide_startstop_t
execute_drive_cmd (ide_drive_t
*drive
,
814 ide_hwif_t
*hwif
= HWIF(drive
);
815 if (rq
->flags
& REQ_DRIVE_TASKFILE
) {
816 ide_task_t
*args
= rq
->special
;
821 hwif
->data_phase
= args
->data_phase
;
823 switch (hwif
->data_phase
) {
824 case TASKFILE_MULTI_OUT
:
826 case TASKFILE_MULTI_IN
:
828 ide_init_sg_cmd(drive
, rq
);
829 ide_map_sg(drive
, rq
);
834 if (args
->tf_out_flags
.all
!= 0)
835 return flagged_taskfile(drive
, args
);
836 return do_rw_taskfile(drive
, args
);
837 } else if (rq
->flags
& REQ_DRIVE_TASK
) {
838 u8
*args
= rq
->buffer
;
844 printk("%s: DRIVE_TASK_CMD ", drive
->name
);
845 printk("cmd=0x%02x ", args
[0]);
846 printk("fr=0x%02x ", args
[1]);
847 printk("ns=0x%02x ", args
[2]);
848 printk("sc=0x%02x ", args
[3]);
849 printk("lcyl=0x%02x ", args
[4]);
850 printk("hcyl=0x%02x ", args
[5]);
851 printk("sel=0x%02x\n", args
[6]);
853 hwif
->OUTB(args
[1], IDE_FEATURE_REG
);
854 hwif
->OUTB(args
[3], IDE_SECTOR_REG
);
855 hwif
->OUTB(args
[4], IDE_LCYL_REG
);
856 hwif
->OUTB(args
[5], IDE_HCYL_REG
);
857 sel
= (args
[6] & ~0x10);
858 if (drive
->select
.b
.unit
)
860 hwif
->OUTB(sel
, IDE_SELECT_REG
);
861 ide_cmd(drive
, args
[0], args
[2], &drive_cmd_intr
);
863 } else if (rq
->flags
& REQ_DRIVE_CMD
) {
864 u8
*args
= rq
->buffer
;
869 printk("%s: DRIVE_CMD ", drive
->name
);
870 printk("cmd=0x%02x ", args
[0]);
871 printk("sc=0x%02x ", args
[1]);
872 printk("fr=0x%02x ", args
[2]);
873 printk("xx=0x%02x\n", args
[3]);
875 if (args
[0] == WIN_SMART
) {
876 hwif
->OUTB(0x4f, IDE_LCYL_REG
);
877 hwif
->OUTB(0xc2, IDE_HCYL_REG
);
878 hwif
->OUTB(args
[2],IDE_FEATURE_REG
);
879 hwif
->OUTB(args
[1],IDE_SECTOR_REG
);
880 ide_cmd(drive
, args
[0], args
[3], &drive_cmd_intr
);
883 hwif
->OUTB(args
[2],IDE_FEATURE_REG
);
884 ide_cmd(drive
, args
[0], args
[1], &drive_cmd_intr
);
890 * NULL is actually a valid way of waiting for
891 * all current requests to be flushed from the queue.
894 printk("%s: DRIVE_CMD (null)\n", drive
->name
);
896 ide_end_drive_cmd(drive
,
897 hwif
->INB(IDE_STATUS_REG
),
898 hwif
->INB(IDE_ERROR_REG
));
903 * start_request - start of I/O and command issuing for IDE
905 * start_request() initiates handling of a new I/O request. It
906 * accepts commands and I/O (read/write) requests. It also does
907 * the final remapping for weird stuff like EZDrive. Once
908 * device mapper can work sector level the EZDrive stuff can go away
910 * FIXME: this function needs a rename
913 static ide_startstop_t
start_request (ide_drive_t
*drive
, struct request
*rq
)
915 ide_startstop_t startstop
;
918 BUG_ON(!(rq
->flags
& REQ_STARTED
));
921 printk("%s: start_request: current=0x%08lx\n",
922 HWIF(drive
)->name
, (unsigned long) rq
);
925 /* bail early if we've exceeded max_failures */
926 if (drive
->max_failures
&& (drive
->failures
> drive
->max_failures
)) {
931 if (blk_fs_request(rq
) &&
932 (drive
->media
== ide_disk
|| drive
->media
== ide_floppy
)) {
933 block
+= drive
->sect0
;
935 /* Yecch - this will shift the entire interval,
936 possibly killing some innocent following sector */
937 if (block
== 0 && drive
->remap_0_to_1
== 1)
938 block
= 1; /* redirect MBR access to EZ-Drive partn table */
940 if (blk_pm_suspend_request(rq
) &&
941 rq
->pm
->pm_step
== ide_pm_state_start_suspend
)
942 /* Mark drive blocked when starting the suspend sequence. */
944 else if (blk_pm_resume_request(rq
) &&
945 rq
->pm
->pm_step
== ide_pm_state_start_resume
) {
947 * The first thing we do on wakeup is to wait for BSY bit to
948 * go away (with a looong timeout) as a drive on this hwif may
949 * just be POSTing itself.
950 * We do that before even selecting as the "other" device on
951 * the bus may be broken enough to walk on our toes at this
956 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive
->name
);
958 rc
= ide_wait_not_busy(HWIF(drive
), 35000);
960 printk(KERN_WARNING
"%s: bus not ready on wakeup\n", drive
->name
);
962 HWIF(drive
)->OUTB(8, HWIF(drive
)->io_ports
[IDE_CONTROL_OFFSET
]);
963 rc
= ide_wait_not_busy(HWIF(drive
), 10000);
965 printk(KERN_WARNING
"%s: drive not ready on wakeup\n", drive
->name
);
969 if (ide_wait_stat(&startstop
, drive
, drive
->ready_stat
, BUSY_STAT
|DRQ_STAT
, WAIT_READY
)) {
970 printk(KERN_ERR
"%s: drive not ready for command\n", drive
->name
);
973 if (!drive
->special
.all
) {
976 if (rq
->flags
& (REQ_DRIVE_CMD
| REQ_DRIVE_TASK
))
977 return execute_drive_cmd(drive
, rq
);
978 else if (rq
->flags
& REQ_DRIVE_TASKFILE
)
979 return execute_drive_cmd(drive
, rq
);
980 else if (blk_pm_request(rq
)) {
982 printk("%s: start_power_step(step: %d)\n",
983 drive
->name
, rq
->pm
->pm_step
);
985 startstop
= ide_start_power_step(drive
, rq
);
986 if (startstop
== ide_stopped
&&
987 rq
->pm
->pm_step
== ide_pm_state_completed
)
988 ide_complete_pm_request(drive
, rq
);
992 drv
= *(ide_driver_t
**)rq
->rq_disk
->private_data
;
993 return drv
->do_request(drive
, rq
, block
);
995 return do_special(drive
);
997 ide_kill_rq(drive
, rq
);
1002 * ide_stall_queue - pause an IDE device
1003 * @drive: drive to stall
1004 * @timeout: time to stall for (jiffies)
1006 * ide_stall_queue() can be used by a drive to give excess bandwidth back
1007 * to the hwgroup by sleeping for timeout jiffies.
1010 void ide_stall_queue (ide_drive_t
*drive
, unsigned long timeout
)
1012 if (timeout
> WAIT_WORSTCASE
)
1013 timeout
= WAIT_WORSTCASE
;
1014 drive
->sleep
= timeout
+ jiffies
;
1015 drive
->sleeping
= 1;
1018 EXPORT_SYMBOL(ide_stall_queue
);
1020 #define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
1023 * choose_drive - select a drive to service
1024 * @hwgroup: hardware group to select on
1026 * choose_drive() selects the next drive which will be serviced.
1027 * This is necessary because the IDE layer can't issue commands
1028 * to both drives on the same cable, unlike SCSI.
1031 static inline ide_drive_t
*choose_drive (ide_hwgroup_t
*hwgroup
)
1033 ide_drive_t
*drive
, *best
;
1037 drive
= hwgroup
->drive
;
1040 * drive is doing pre-flush, ordered write, post-flush sequence. even
1041 * though that is 3 requests, it must be seen as a single transaction.
1042 * we must not preempt this drive until that is complete
1044 if (blk_queue_flushing(drive
->queue
)) {
1046 * small race where queue could get replugged during
1047 * the 3-request flush cycle, just yank the plug since
1048 * we want it to finish asap
1050 blk_remove_plug(drive
->queue
);
1055 if ((!drive
->sleeping
|| time_after_eq(jiffies
, drive
->sleep
))
1056 && !elv_queue_empty(drive
->queue
)) {
1058 || (drive
->sleeping
&& (!best
->sleeping
|| time_before(drive
->sleep
, best
->sleep
)))
1059 || (!best
->sleeping
&& time_before(WAKEUP(drive
), WAKEUP(best
))))
1061 if (!blk_queue_plugged(drive
->queue
))
1065 } while ((drive
= drive
->next
) != hwgroup
->drive
);
1066 if (best
&& best
->nice1
&& !best
->sleeping
&& best
!= hwgroup
->drive
&& best
->service_time
> WAIT_MIN_SLEEP
) {
1067 long t
= (signed long)(WAKEUP(best
) - jiffies
);
1068 if (t
>= WAIT_MIN_SLEEP
) {
1070 * We *may* have some time to spare, but first let's see if
1071 * someone can potentially benefit from our nice mood today..
1075 if (!drive
->sleeping
1076 && time_before(jiffies
- best
->service_time
, WAKEUP(drive
))
1077 && time_before(WAKEUP(drive
), jiffies
+ t
))
1079 ide_stall_queue(best
, min_t(long, t
, 10 * WAIT_MIN_SLEEP
));
1082 } while ((drive
= drive
->next
) != best
);
1089 * Issue a new request to a drive from hwgroup
1090 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1092 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1093 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1094 * may have both interfaces in a single hwgroup to "serialize" access.
1095 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1096 * together into one hwgroup for serialized access.
1098 * Note also that several hwgroups can end up sharing a single IRQ,
1099 * possibly along with many other devices. This is especially common in
1100 * PCI-based systems with off-board IDE controller cards.
1102 * The IDE driver uses the single global ide_lock spinlock to protect
1103 * access to the request queues, and to protect the hwgroup->busy flag.
1105 * The first thread into the driver for a particular hwgroup sets the
1106 * hwgroup->busy flag to indicate that this hwgroup is now active,
1107 * and then initiates processing of the top request from the request queue.
1109 * Other threads attempting entry notice the busy setting, and will simply
1110 * queue their new requests and exit immediately. Note that hwgroup->busy
1111 * remains set even when the driver is merely awaiting the next interrupt.
1112 * Thus, the meaning is "this hwgroup is busy processing a request".
1114 * When processing of a request completes, the completing thread or IRQ-handler
1115 * will start the next request from the queue. If no more work remains,
1116 * the driver will clear the hwgroup->busy flag and exit.
1118 * The ide_lock (spinlock) is used to protect all access to the
1119 * hwgroup->busy flag, but is otherwise not needed for most processing in
1120 * the driver. This makes the driver much more friendlier to shared IRQs
1121 * than previous designs, while remaining 100% (?) SMP safe and capable.
1123 static void ide_do_request (ide_hwgroup_t
*hwgroup
, int masked_irq
)
1128 ide_startstop_t startstop
;
1131 /* for atari only: POSSIBLY BROKEN HERE(?) */
1132 ide_get_lock(ide_intr
, hwgroup
);
1134 /* caller must own ide_lock */
1135 BUG_ON(!irqs_disabled());
1137 while (!hwgroup
->busy
) {
1139 drive
= choose_drive(hwgroup
);
1140 if (drive
== NULL
) {
1142 unsigned long sleep
= 0; /* shut up, gcc */
1144 drive
= hwgroup
->drive
;
1146 if (drive
->sleeping
&& (!sleeping
|| time_before(drive
->sleep
, sleep
))) {
1148 sleep
= drive
->sleep
;
1150 } while ((drive
= drive
->next
) != hwgroup
->drive
);
1153 * Take a short snooze, and then wake up this hwgroup again.
1154 * This gives other hwgroups on the same a chance to
1155 * play fairly with us, just in case there are big differences
1156 * in relative throughputs.. don't want to hog the cpu too much.
1158 if (time_before(sleep
, jiffies
+ WAIT_MIN_SLEEP
))
1159 sleep
= jiffies
+ WAIT_MIN_SLEEP
;
1161 if (timer_pending(&hwgroup
->timer
))
1162 printk(KERN_CRIT
"ide_set_handler: timer already active\n");
1164 /* so that ide_timer_expiry knows what to do */
1165 hwgroup
->sleeping
= 1;
1166 mod_timer(&hwgroup
->timer
, sleep
);
1167 /* we purposely leave hwgroup->busy==1
1170 /* Ugly, but how can we sleep for the lock
1171 * otherwise? perhaps from tq_disk?
1174 /* for atari only */
1179 /* no more work for this hwgroup (for now) */
1184 if (hwgroup
->hwif
->sharing_irq
&&
1185 hwif
!= hwgroup
->hwif
&&
1186 hwif
->io_ports
[IDE_CONTROL_OFFSET
]) {
1187 /* set nIEN for previous hwif */
1188 SELECT_INTERRUPT(drive
);
1190 hwgroup
->hwif
= hwif
;
1191 hwgroup
->drive
= drive
;
1192 drive
->sleeping
= 0;
1193 drive
->service_start
= jiffies
;
1195 if (blk_queue_plugged(drive
->queue
)) {
1196 printk(KERN_ERR
"ide: huh? queue was plugged!\n");
1201 * we know that the queue isn't empty, but this can happen
1202 * if the q->prep_rq_fn() decides to kill a request
1204 rq
= elv_next_request(drive
->queue
);
1211 * Sanity: don't accept a request that isn't a PM request
1212 * if we are currently power managed. This is very important as
1213 * blk_stop_queue() doesn't prevent the elv_next_request()
1214 * above to return us whatever is in the queue. Since we call
1215 * ide_do_request() ourselves, we end up taking requests while
1216 * the queue is blocked...
1218 * We let requests forced at head of queue with ide-preempt
1219 * though. I hope that doesn't happen too much, hopefully not
1220 * unless the subdriver triggers such a thing in its own PM
1223 * We count how many times we loop here to make sure we service
1224 * all drives in the hwgroup without looping for ever
1226 if (drive
->blocked
&& !blk_pm_request(rq
) && !(rq
->flags
& REQ_PREEMPT
)) {
1227 drive
= drive
->next
? drive
->next
: hwgroup
->drive
;
1228 if (loops
++ < 4 && !blk_queue_plugged(drive
->queue
))
1230 /* We clear busy, there should be no pending ATA command at this point. */
1238 * Some systems have trouble with IDE IRQs arriving while
1239 * the driver is still setting things up. So, here we disable
1240 * the IRQ used by this interface while the request is being started.
1241 * This may look bad at first, but pretty much the same thing
1242 * happens anyway when any interrupt comes in, IDE or otherwise
1243 * -- the kernel masks the IRQ while it is being handled.
1245 if (masked_irq
!= IDE_NO_IRQ
&& hwif
->irq
!= masked_irq
)
1246 disable_irq_nosync(hwif
->irq
);
1247 spin_unlock(&ide_lock
);
1249 /* allow other IRQs while we start this request */
1250 startstop
= start_request(drive
, rq
);
1251 spin_lock_irq(&ide_lock
);
1252 if (masked_irq
!= IDE_NO_IRQ
&& hwif
->irq
!= masked_irq
)
1253 enable_irq(hwif
->irq
);
1254 if (startstop
== ide_stopped
)
1260 * Passes the stuff to ide_do_request
1262 void do_ide_request(request_queue_t
*q
)
1264 ide_drive_t
*drive
= q
->queuedata
;
1266 ide_do_request(HWGROUP(drive
), IDE_NO_IRQ
);
1270 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1271 * retry the current request in pio mode instead of risking tossing it
1274 static ide_startstop_t
ide_dma_timeout_retry(ide_drive_t
*drive
, int error
)
1276 ide_hwif_t
*hwif
= HWIF(drive
);
1278 ide_startstop_t ret
= ide_stopped
;
1281 * end current dma transaction
1285 printk(KERN_WARNING
"%s: DMA timeout error\n", drive
->name
);
1286 (void)HWIF(drive
)->ide_dma_end(drive
);
1287 ret
= ide_error(drive
, "dma timeout error",
1288 hwif
->INB(IDE_STATUS_REG
));
1290 printk(KERN_WARNING
"%s: DMA timeout retry\n", drive
->name
);
1291 (void) hwif
->ide_dma_timeout(drive
);
1295 * disable dma for now, but remember that we did so because of
1296 * a timeout -- we'll reenable after we finish this next request
1297 * (or rather the first chunk of it) in pio.
1300 drive
->state
= DMA_PIO_RETRY
;
1301 (void) hwif
->ide_dma_off_quietly(drive
);
1304 * un-busy drive etc (hwgroup->busy is cleared on return) and
1305 * make sure request is sane
1307 rq
= HWGROUP(drive
)->rq
;
1308 HWGROUP(drive
)->rq
= NULL
;
1315 rq
->sector
= rq
->bio
->bi_sector
;
1316 rq
->current_nr_sectors
= bio_iovec(rq
->bio
)->bv_len
>> 9;
1317 rq
->hard_cur_sectors
= rq
->current_nr_sectors
;
1318 rq
->buffer
= bio_data(rq
->bio
);
1324 * ide_timer_expiry - handle lack of an IDE interrupt
1325 * @data: timer callback magic (hwgroup)
1327 * An IDE command has timed out before the expected drive return
1328 * occurred. At this point we attempt to clean up the current
1329 * mess. If the current handler includes an expiry handler then
1330 * we invoke the expiry handler, and providing it is happy the
1331 * work is done. If that fails we apply generic recovery rules
1332 * invoking the handler and checking the drive DMA status. We
1333 * have an excessively incestuous relationship with the DMA
1334 * logic that wants cleaning up.
1337 void ide_timer_expiry (unsigned long data
)
1339 ide_hwgroup_t
*hwgroup
= (ide_hwgroup_t
*) data
;
1340 ide_handler_t
*handler
;
1341 ide_expiry_t
*expiry
;
1342 unsigned long flags
;
1343 unsigned long wait
= -1;
1345 spin_lock_irqsave(&ide_lock
, flags
);
1347 if ((handler
= hwgroup
->handler
) == NULL
) {
1349 * Either a marginal timeout occurred
1350 * (got the interrupt just as timer expired),
1351 * or we were "sleeping" to give other devices a chance.
1352 * Either way, we don't really want to complain about anything.
1354 if (hwgroup
->sleeping
) {
1355 hwgroup
->sleeping
= 0;
1359 ide_drive_t
*drive
= hwgroup
->drive
;
1361 printk(KERN_ERR
"ide_timer_expiry: hwgroup->drive was NULL\n");
1362 hwgroup
->handler
= NULL
;
1365 ide_startstop_t startstop
= ide_stopped
;
1366 if (!hwgroup
->busy
) {
1367 hwgroup
->busy
= 1; /* paranoia */
1368 printk(KERN_ERR
"%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive
->name
);
1370 if ((expiry
= hwgroup
->expiry
) != NULL
) {
1372 if ((wait
= expiry(drive
)) > 0) {
1374 hwgroup
->timer
.expires
= jiffies
+ wait
;
1375 add_timer(&hwgroup
->timer
);
1376 spin_unlock_irqrestore(&ide_lock
, flags
);
1380 hwgroup
->handler
= NULL
;
1382 * We need to simulate a real interrupt when invoking
1383 * the handler() function, which means we need to
1384 * globally mask the specific IRQ:
1386 spin_unlock(&ide_lock
);
1388 #if DISABLE_IRQ_NOSYNC
1389 disable_irq_nosync(hwif
->irq
);
1391 /* disable_irq_nosync ?? */
1392 disable_irq(hwif
->irq
);
1393 #endif /* DISABLE_IRQ_NOSYNC */
1395 * as if we were handling an interrupt */
1396 local_irq_disable();
1397 if (hwgroup
->polling
) {
1398 startstop
= handler(drive
);
1399 } else if (drive_is_ready(drive
)) {
1400 if (drive
->waiting_for_dma
)
1401 (void) hwgroup
->hwif
->ide_dma_lostirq(drive
);
1402 (void)ide_ack_intr(hwif
);
1403 printk(KERN_WARNING
"%s: lost interrupt\n", drive
->name
);
1404 startstop
= handler(drive
);
1406 if (drive
->waiting_for_dma
) {
1407 startstop
= ide_dma_timeout_retry(drive
, wait
);
1410 ide_error(drive
, "irq timeout", hwif
->INB(IDE_STATUS_REG
));
1412 drive
->service_time
= jiffies
- drive
->service_start
;
1413 spin_lock_irq(&ide_lock
);
1414 enable_irq(hwif
->irq
);
1415 if (startstop
== ide_stopped
)
1419 ide_do_request(hwgroup
, IDE_NO_IRQ
);
1420 spin_unlock_irqrestore(&ide_lock
, flags
);
1424 * unexpected_intr - handle an unexpected IDE interrupt
1425 * @irq: interrupt line
1426 * @hwgroup: hwgroup being processed
1428 * There's nothing really useful we can do with an unexpected interrupt,
1429 * other than reading the status register (to clear it), and logging it.
1430 * There should be no way that an irq can happen before we're ready for it,
1431 * so we needn't worry much about losing an "important" interrupt here.
1433 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1434 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1435 * looks "good", we just ignore the interrupt completely.
1437 * This routine assumes __cli() is in effect when called.
1439 * If an unexpected interrupt happens on irq15 while we are handling irq14
1440 * and if the two interfaces are "serialized" (CMD640), then it looks like
1441 * we could screw up by interfering with a new request being set up for
1444 * In reality, this is a non-issue. The new command is not sent unless
1445 * the drive is ready to accept one, in which case we know the drive is
1446 * not trying to interrupt us. And ide_set_handler() is always invoked
1447 * before completing the issuance of any new drive command, so we will not
1448 * be accidentally invoked as a result of any valid command completion
1451 * Note that we must walk the entire hwgroup here. We know which hwif
1452 * is doing the current command, but we don't know which hwif burped
1456 static void unexpected_intr (int irq
, ide_hwgroup_t
*hwgroup
)
1459 ide_hwif_t
*hwif
= hwgroup
->hwif
;
1462 * handle the unexpected interrupt
1465 if (hwif
->irq
== irq
) {
1466 stat
= hwif
->INB(hwif
->io_ports
[IDE_STATUS_OFFSET
]);
1467 if (!OK_STAT(stat
, READY_STAT
, BAD_STAT
)) {
1468 /* Try to not flood the console with msgs */
1469 static unsigned long last_msgtime
, count
;
1471 if (time_after(jiffies
, last_msgtime
+ HZ
)) {
1472 last_msgtime
= jiffies
;
1473 printk(KERN_ERR
"%s%s: unexpected interrupt, "
1474 "status=0x%02x, count=%ld\n",
1476 (hwif
->next
==hwgroup
->hwif
) ? "" : "(?)", stat
, count
);
1480 } while ((hwif
= hwif
->next
) != hwgroup
->hwif
);
1484 * ide_intr - default IDE interrupt handler
1485 * @irq: interrupt number
1486 * @dev_id: hwif group
1487 * @regs: unused weirdness from the kernel irq layer
1489 * This is the default IRQ handler for the IDE layer. You should
1490 * not need to override it. If you do be aware it is subtle in
1493 * hwgroup->hwif is the interface in the group currently performing
1494 * a command. hwgroup->drive is the drive and hwgroup->handler is
1495 * the IRQ handler to call. As we issue a command the handlers
1496 * step through multiple states, reassigning the handler to the
1497 * next step in the process. Unlike a smart SCSI controller IDE
1498 * expects the main processor to sequence the various transfer
1499 * stages. We also manage a poll timer to catch up with most
1500 * timeout situations. There are still a few where the handlers
1501 * don't ever decide to give up.
1503 * The handler eventually returns ide_stopped to indicate the
1504 * request completed. At this point we issue the next request
1505 * on the hwgroup and the process begins again.
1508 irqreturn_t
ide_intr (int irq
, void *dev_id
, struct pt_regs
*regs
)
1510 unsigned long flags
;
1511 ide_hwgroup_t
*hwgroup
= (ide_hwgroup_t
*)dev_id
;
1514 ide_handler_t
*handler
;
1515 ide_startstop_t startstop
;
1517 spin_lock_irqsave(&ide_lock
, flags
);
1518 hwif
= hwgroup
->hwif
;
1520 if (!ide_ack_intr(hwif
)) {
1521 spin_unlock_irqrestore(&ide_lock
, flags
);
1525 if ((handler
= hwgroup
->handler
) == NULL
|| hwgroup
->polling
) {
1527 * Not expecting an interrupt from this drive.
1528 * That means this could be:
1529 * (1) an interrupt from another PCI device
1530 * sharing the same PCI INT# as us.
1531 * or (2) a drive just entered sleep or standby mode,
1532 * and is interrupting to let us know.
1533 * or (3) a spurious interrupt of unknown origin.
1535 * For PCI, we cannot tell the difference,
1536 * so in that case we just ignore it and hope it goes away.
1538 * FIXME: unexpected_intr should be hwif-> then we can
1539 * remove all the ifdef PCI crap
1541 #ifdef CONFIG_BLK_DEV_IDEPCI
1542 if (hwif
->pci_dev
&& !hwif
->pci_dev
->vendor
)
1543 #endif /* CONFIG_BLK_DEV_IDEPCI */
1546 * Probably not a shared PCI interrupt,
1547 * so we can safely try to do something about it:
1549 unexpected_intr(irq
, hwgroup
);
1550 #ifdef CONFIG_BLK_DEV_IDEPCI
1553 * Whack the status register, just in case
1554 * we have a leftover pending IRQ.
1556 (void) hwif
->INB(hwif
->io_ports
[IDE_STATUS_OFFSET
]);
1557 #endif /* CONFIG_BLK_DEV_IDEPCI */
1559 spin_unlock_irqrestore(&ide_lock
, flags
);
1562 drive
= hwgroup
->drive
;
1565 * This should NEVER happen, and there isn't much
1566 * we could do about it here.
1568 * [Note - this can occur if the drive is hot unplugged]
1570 spin_unlock_irqrestore(&ide_lock
, flags
);
1573 if (!drive_is_ready(drive
)) {
1575 * This happens regularly when we share a PCI IRQ with
1576 * another device. Unfortunately, it can also happen
1577 * with some buggy drives that trigger the IRQ before
1578 * their status register is up to date. Hopefully we have
1579 * enough advance overhead that the latter isn't a problem.
1581 spin_unlock_irqrestore(&ide_lock
, flags
);
1584 if (!hwgroup
->busy
) {
1585 hwgroup
->busy
= 1; /* paranoia */
1586 printk(KERN_ERR
"%s: ide_intr: hwgroup->busy was 0 ??\n", drive
->name
);
1588 hwgroup
->handler
= NULL
;
1589 del_timer(&hwgroup
->timer
);
1590 spin_unlock(&ide_lock
);
1594 /* service this interrupt, may set handler for next interrupt */
1595 startstop
= handler(drive
);
1596 spin_lock_irq(&ide_lock
);
1599 * Note that handler() may have set things up for another
1600 * interrupt to occur soon, but it cannot happen until
1601 * we exit from this routine, because it will be the
1602 * same irq as is currently being serviced here, and Linux
1603 * won't allow another of the same (on any CPU) until we return.
1605 drive
->service_time
= jiffies
- drive
->service_start
;
1606 if (startstop
== ide_stopped
) {
1607 if (hwgroup
->handler
== NULL
) { /* paranoia */
1609 ide_do_request(hwgroup
, hwif
->irq
);
1611 printk(KERN_ERR
"%s: ide_intr: huh? expected NULL handler "
1612 "on exit\n", drive
->name
);
1615 spin_unlock_irqrestore(&ide_lock
, flags
);
1620 * ide_init_drive_cmd - initialize a drive command request
1621 * @rq: request object
1623 * Initialize a request before we fill it in and send it down to
1624 * ide_do_drive_cmd. Commands must be set up by this function. Right
1625 * now it doesn't do a lot, but if that changes abusers will have a
1629 void ide_init_drive_cmd (struct request
*rq
)
1631 memset(rq
, 0, sizeof(*rq
));
1632 rq
->flags
= REQ_DRIVE_CMD
;
1636 EXPORT_SYMBOL(ide_init_drive_cmd
);
1639 * ide_do_drive_cmd - issue IDE special command
1640 * @drive: device to issue command
1641 * @rq: request to issue
1642 * @action: action for processing
1644 * This function issues a special IDE device request
1645 * onto the request queue.
1647 * If action is ide_wait, then the rq is queued at the end of the
1648 * request queue, and the function sleeps until it has been processed.
1649 * This is for use when invoked from an ioctl handler.
1651 * If action is ide_preempt, then the rq is queued at the head of
1652 * the request queue, displacing the currently-being-processed
1653 * request and this function returns immediately without waiting
1654 * for the new rq to be completed. This is VERY DANGEROUS, and is
1655 * intended for careful use by the ATAPI tape/cdrom driver code.
1657 * If action is ide_end, then the rq is queued at the end of the
1658 * request queue, and the function returns immediately without waiting
1659 * for the new rq to be completed. This is again intended for careful
1660 * use by the ATAPI tape/cdrom driver code.
1663 int ide_do_drive_cmd (ide_drive_t
*drive
, struct request
*rq
, ide_action_t action
)
1665 unsigned long flags
;
1666 ide_hwgroup_t
*hwgroup
= HWGROUP(drive
);
1667 DECLARE_COMPLETION(wait
);
1668 int where
= ELEVATOR_INSERT_BACK
, err
;
1669 int must_wait
= (action
== ide_wait
|| action
== ide_head_wait
);
1672 rq
->rq_status
= RQ_ACTIVE
;
1675 * we need to hold an extra reference to request for safe inspection
1680 rq
->waiting
= &wait
;
1681 rq
->end_io
= blk_end_sync_rq
;
1684 spin_lock_irqsave(&ide_lock
, flags
);
1685 if (action
== ide_preempt
)
1687 if (action
== ide_preempt
|| action
== ide_head_wait
) {
1688 where
= ELEVATOR_INSERT_FRONT
;
1689 rq
->flags
|= REQ_PREEMPT
;
1691 __elv_add_request(drive
->queue
, rq
, where
, 0);
1692 ide_do_request(hwgroup
, IDE_NO_IRQ
);
1693 spin_unlock_irqrestore(&ide_lock
, flags
);
1697 wait_for_completion(&wait
);
1702 blk_put_request(rq
);
1708 EXPORT_SYMBOL(ide_do_drive_cmd
);