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/module.h>
28 #include <linux/types.h>
29 #include <linux/string.h>
30 #include <linux/kernel.h>
31 #include <linux/timer.h>
33 #include <linux/interrupt.h>
34 #include <linux/major.h>
35 #include <linux/errno.h>
36 #include <linux/genhd.h>
37 #include <linux/blkpg.h>
38 #include <linux/slab.h>
39 #include <linux/init.h>
40 #include <linux/pci.h>
41 #include <linux/delay.h>
42 #include <linux/ide.h>
43 #include <linux/hdreg.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>
51 #include <linux/bitops.h>
53 #include <asm/byteorder.h>
55 #include <asm/uaccess.h>
58 static int __ide_end_request(ide_drive_t *drive, struct request *rq,
59 int uptodate, unsigned int nr_bytes, int dequeue)
65 error = uptodate ? uptodate : -EIO;
68 * if failfast is set on a request, override number of sectors and
69 * complete the whole request right now
71 if (blk_noretry_request(rq) && error)
72 nr_bytes = rq->hard_nr_sectors << 9;
74 if (!blk_fs_request(rq) && error && !rq->errors)
78 * decide whether to reenable DMA -- 3 is a random magic for now,
79 * if we DMA timeout more than 3 times, just stay in PIO
81 if ((drive->dev_flags & IDE_DFLAG_DMA_PIO_RETRY) &&
82 drive->retry_pio <= 3) {
83 drive->dev_flags &= ~IDE_DFLAG_DMA_PIO_RETRY;
87 if (!blk_end_request(rq, error, nr_bytes))
90 if (ret == 0 && dequeue)
91 drive->hwif->rq = NULL;
97 * ide_end_request - complete an IDE I/O
98 * @drive: IDE device for the I/O
100 * @nr_sectors: number of sectors completed
102 * This is our end_request wrapper function. We complete the I/O
103 * update random number input and dequeue the request, which if
104 * it was tagged may be out of order.
107 int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
109 unsigned int nr_bytes = nr_sectors << 9;
110 struct request *rq = drive->hwif->rq;
113 if (blk_pc_request(rq))
114 nr_bytes = rq->data_len;
116 nr_bytes = rq->hard_cur_sectors << 9;
119 return __ide_end_request(drive, rq, uptodate, nr_bytes, 1);
121 EXPORT_SYMBOL(ide_end_request);
124 * ide_end_dequeued_request - complete an IDE I/O
125 * @drive: IDE device for the I/O
127 * @nr_sectors: number of sectors completed
129 * Complete an I/O that is no longer on the request queue. This
130 * typically occurs when we pull the request and issue a REQUEST_SENSE.
131 * We must still finish the old request but we must not tamper with the
132 * queue in the meantime.
134 * NOTE: This path does not handle barrier, but barrier is not supported
138 int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq,
139 int uptodate, int nr_sectors)
141 BUG_ON(!blk_rq_started(rq));
143 return __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0);
145 EXPORT_SYMBOL_GPL(ide_end_dequeued_request);
148 * ide_end_drive_cmd - end an explicit drive command
153 * Clean up after success/failure of an explicit drive command.
154 * These get thrown onto the queue so they are synchronized with
155 * real I/O operations on the drive.
157 * In LBA48 mode we have to read the register set twice to get
158 * all the extra information out.
161 void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
163 ide_hwif_t *hwif = drive->hwif;
164 struct request *rq = hwif->rq;
166 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
167 ide_task_t *task = (ide_task_t *)rq->special;
170 struct ide_taskfile *tf = &task->tf;
175 drive->hwif->tp_ops->tf_read(drive, task);
177 if (task->tf_flags & IDE_TFLAG_DYN)
180 } else if (blk_pm_request(rq)) {
181 struct request_pm_state *pm = rq->data;
183 ide_complete_power_step(drive, rq);
184 if (pm->pm_step == IDE_PM_COMPLETED)
185 ide_complete_pm_request(drive, rq);
193 if (unlikely(blk_end_request(rq, (rq->errors ? -EIO : 0),
197 EXPORT_SYMBOL(ide_end_drive_cmd);
199 static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
204 drv = *(ide_driver_t **)rq->rq_disk->private_data;
205 drv->end_request(drive, 0, 0);
207 ide_end_request(drive, 0, 0);
210 static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
212 ide_hwif_t *hwif = drive->hwif;
214 if ((stat & ATA_BUSY) ||
215 ((stat & ATA_DF) && (drive->dev_flags & IDE_DFLAG_NOWERR) == 0)) {
216 /* other bits are useless when BUSY */
217 rq->errors |= ERROR_RESET;
218 } else if (stat & ATA_ERR) {
219 /* err has different meaning on cdrom and tape */
220 if (err == ATA_ABORTED) {
221 if ((drive->dev_flags & IDE_DFLAG_LBA) &&
222 /* some newer drives don't support ATA_CMD_INIT_DEV_PARAMS */
223 hwif->tp_ops->read_status(hwif) == ATA_CMD_INIT_DEV_PARAMS)
225 } else if ((err & BAD_CRC) == BAD_CRC) {
226 /* UDMA crc error, just retry the operation */
228 } else if (err & (ATA_BBK | ATA_UNC)) {
229 /* retries won't help these */
230 rq->errors = ERROR_MAX;
231 } else if (err & ATA_TRK0NF) {
232 /* help it find track zero */
233 rq->errors |= ERROR_RECAL;
237 if ((stat & ATA_DRQ) && rq_data_dir(rq) == READ &&
238 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) {
239 int nsect = drive->mult_count ? drive->mult_count : 1;
241 ide_pad_transfer(drive, READ, nsect * SECTOR_SIZE);
244 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
245 ide_kill_rq(drive, rq);
249 if (hwif->tp_ops->read_status(hwif) & (ATA_BUSY | ATA_DRQ))
250 rq->errors |= ERROR_RESET;
252 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
254 return ide_do_reset(drive);
257 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
258 drive->special.b.recalibrate = 1;
265 static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
267 ide_hwif_t *hwif = drive->hwif;
269 if ((stat & ATA_BUSY) ||
270 ((stat & ATA_DF) && (drive->dev_flags & IDE_DFLAG_NOWERR) == 0)) {
271 /* other bits are useless when BUSY */
272 rq->errors |= ERROR_RESET;
274 /* add decoding error stuff */
277 if (hwif->tp_ops->read_status(hwif) & (ATA_BUSY | ATA_DRQ))
279 hwif->tp_ops->exec_command(hwif, ATA_CMD_IDLEIMMEDIATE);
281 if (rq->errors >= ERROR_MAX) {
282 ide_kill_rq(drive, rq);
284 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
286 return ide_do_reset(drive);
295 __ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
297 if (drive->media == ide_disk)
298 return ide_ata_error(drive, rq, stat, err);
299 return ide_atapi_error(drive, rq, stat, err);
302 EXPORT_SYMBOL_GPL(__ide_error);
305 * ide_error - handle an error on the IDE
306 * @drive: drive the error occurred on
307 * @msg: message to report
310 * ide_error() takes action based on the error returned by the drive.
311 * For normal I/O that may well include retries. We deal with
312 * both new-style (taskfile) and old style command handling here.
313 * In the case of taskfile command handling there is work left to
317 ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
322 err = ide_dump_status(drive, msg, stat);
324 rq = drive->hwif->rq;
328 /* retry only "normal" I/O: */
329 if (!blk_fs_request(rq)) {
331 ide_end_drive_cmd(drive, stat, err);
338 drv = *(ide_driver_t **)rq->rq_disk->private_data;
339 return drv->error(drive, rq, stat, err);
341 return __ide_error(drive, rq, stat, err);
344 EXPORT_SYMBOL_GPL(ide_error);
346 static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
348 tf->nsect = drive->sect;
349 tf->lbal = drive->sect;
350 tf->lbam = drive->cyl;
351 tf->lbah = drive->cyl >> 8;
352 tf->device = (drive->head - 1) | drive->select;
353 tf->command = ATA_CMD_INIT_DEV_PARAMS;
356 static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
358 tf->nsect = drive->sect;
359 tf->command = ATA_CMD_RESTORE;
362 static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
364 tf->nsect = drive->mult_req;
365 tf->command = ATA_CMD_SET_MULTI;
368 static ide_startstop_t ide_disk_special(ide_drive_t *drive)
370 special_t *s = &drive->special;
373 memset(&args, 0, sizeof(ide_task_t));
374 args.data_phase = TASKFILE_NO_DATA;
376 if (s->b.set_geometry) {
377 s->b.set_geometry = 0;
378 ide_tf_set_specify_cmd(drive, &args.tf);
379 } else if (s->b.recalibrate) {
380 s->b.recalibrate = 0;
381 ide_tf_set_restore_cmd(drive, &args.tf);
382 } else if (s->b.set_multmode) {
383 s->b.set_multmode = 0;
384 ide_tf_set_setmult_cmd(drive, &args.tf);
386 int special = s->all;
388 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
392 args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE |
393 IDE_TFLAG_CUSTOM_HANDLER;
395 do_rw_taskfile(drive, &args);
401 * do_special - issue some special commands
402 * @drive: drive the command is for
404 * do_special() is used to issue ATA_CMD_INIT_DEV_PARAMS,
405 * ATA_CMD_RESTORE and ATA_CMD_SET_MULTI commands to a drive.
407 * It used to do much more, but has been scaled back.
410 static ide_startstop_t do_special (ide_drive_t *drive)
412 special_t *s = &drive->special;
415 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
417 if (drive->media == ide_disk)
418 return ide_disk_special(drive);
425 void ide_map_sg(ide_drive_t *drive, struct request *rq)
427 ide_hwif_t *hwif = drive->hwif;
428 struct scatterlist *sg = hwif->sg_table;
430 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
431 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
433 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
438 EXPORT_SYMBOL_GPL(ide_map_sg);
440 void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
442 ide_hwif_t *hwif = drive->hwif;
444 hwif->nsect = hwif->nleft = rq->nr_sectors;
449 EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
452 * execute_drive_command - issue special drive command
453 * @drive: the drive to issue the command on
454 * @rq: the request structure holding the command
456 * execute_drive_cmd() issues a special drive command, usually
457 * initiated by ioctl() from the external hdparm program. The
458 * command can be a drive command, drive task or taskfile
459 * operation. Weirdly you can call it with NULL to wait for
460 * all commands to finish. Don't do this as that is due to change
463 static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
466 ide_hwif_t *hwif = HWIF(drive);
467 ide_task_t *task = rq->special;
470 hwif->data_phase = task->data_phase;
472 switch (hwif->data_phase) {
473 case TASKFILE_MULTI_OUT:
475 case TASKFILE_MULTI_IN:
477 ide_init_sg_cmd(drive, rq);
478 ide_map_sg(drive, rq);
483 return do_rw_taskfile(drive, task);
487 * NULL is actually a valid way of waiting for
488 * all current requests to be flushed from the queue.
491 printk("%s: DRIVE_CMD (null)\n", drive->name);
493 ide_end_drive_cmd(drive, hwif->tp_ops->read_status(hwif),
494 ide_read_error(drive));
499 int ide_devset_execute(ide_drive_t *drive, const struct ide_devset *setting,
502 struct request_queue *q = drive->queue;
506 if (!(setting->flags & DS_SYNC))
507 return setting->set(drive, arg);
509 rq = blk_get_request(q, READ, __GFP_WAIT);
510 rq->cmd_type = REQ_TYPE_SPECIAL;
512 rq->cmd[0] = REQ_DEVSET_EXEC;
513 *(int *)&rq->cmd[1] = arg;
514 rq->special = setting->set;
516 if (blk_execute_rq(q, NULL, rq, 0))
522 EXPORT_SYMBOL_GPL(ide_devset_execute);
524 static ide_startstop_t ide_special_rq(ide_drive_t *drive, struct request *rq)
528 if (cmd == REQ_PARK_HEADS || cmd == REQ_UNPARK_HEADS) {
530 struct ide_taskfile *tf = &task.tf;
532 memset(&task, 0, sizeof(task));
533 if (cmd == REQ_PARK_HEADS) {
534 drive->sleep = *(unsigned long *)rq->special;
535 drive->dev_flags |= IDE_DFLAG_SLEEPING;
536 tf->command = ATA_CMD_IDLEIMMEDIATE;
541 task.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
542 } else /* cmd == REQ_UNPARK_HEADS */
543 tf->command = ATA_CMD_CHK_POWER;
545 task.tf_flags |= IDE_TFLAG_TF | IDE_TFLAG_DEVICE;
547 drive->hwif->data_phase = task.data_phase = TASKFILE_NO_DATA;
548 return do_rw_taskfile(drive, &task);
552 case REQ_DEVSET_EXEC:
554 int err, (*setfunc)(ide_drive_t *, int) = rq->special;
556 err = setfunc(drive, *(int *)&rq->cmd[1]);
561 ide_end_request(drive, err, 0);
564 case REQ_DRIVE_RESET:
565 return ide_do_reset(drive);
567 blk_dump_rq_flags(rq, "ide_special_rq - bad request");
568 ide_end_request(drive, 0, 0);
574 * start_request - start of I/O and command issuing for IDE
576 * start_request() initiates handling of a new I/O request. It
577 * accepts commands and I/O (read/write) requests.
579 * FIXME: this function needs a rename
582 static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
584 ide_startstop_t startstop;
586 BUG_ON(!blk_rq_started(rq));
589 printk("%s: start_request: current=0x%08lx\n",
590 HWIF(drive)->name, (unsigned long) rq);
593 /* bail early if we've exceeded max_failures */
594 if (drive->max_failures && (drive->failures > drive->max_failures)) {
595 rq->cmd_flags |= REQ_FAILED;
599 if (blk_pm_request(rq))
600 ide_check_pm_state(drive, rq);
603 if (ide_wait_stat(&startstop, drive, drive->ready_stat,
604 ATA_BUSY | ATA_DRQ, WAIT_READY)) {
605 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
608 if (!drive->special.all) {
612 * We reset the drive so we need to issue a SETFEATURES.
613 * Do it _after_ do_special() restored device parameters.
615 if (drive->current_speed == 0xff)
616 ide_config_drive_speed(drive, drive->desired_speed);
618 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
619 return execute_drive_cmd(drive, rq);
620 else if (blk_pm_request(rq)) {
621 struct request_pm_state *pm = rq->data;
623 printk("%s: start_power_step(step: %d)\n",
624 drive->name, pm->pm_step);
626 startstop = ide_start_power_step(drive, rq);
627 if (startstop == ide_stopped &&
628 pm->pm_step == IDE_PM_COMPLETED)
629 ide_complete_pm_request(drive, rq);
631 } else if (!rq->rq_disk && blk_special_request(rq))
633 * TODO: Once all ULDs have been modified to
634 * check for specific op codes rather than
635 * blindly accepting any special request, the
636 * check for ->rq_disk above may be replaced
637 * by a more suitable mechanism or even
640 return ide_special_rq(drive, rq);
642 drv = *(ide_driver_t **)rq->rq_disk->private_data;
644 return drv->do_request(drive, rq, rq->sector);
646 return do_special(drive);
648 ide_kill_rq(drive, rq);
653 * ide_stall_queue - pause an IDE device
654 * @drive: drive to stall
655 * @timeout: time to stall for (jiffies)
657 * ide_stall_queue() can be used by a drive to give excess bandwidth back
658 * to the port by sleeping for timeout jiffies.
661 void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
663 if (timeout > WAIT_WORSTCASE)
664 timeout = WAIT_WORSTCASE;
665 drive->sleep = timeout + jiffies;
666 drive->dev_flags |= IDE_DFLAG_SLEEPING;
668 EXPORT_SYMBOL(ide_stall_queue);
670 static inline int ide_lock_port(ide_hwif_t *hwif)
680 static inline void ide_unlock_port(ide_hwif_t *hwif)
685 static inline int ide_lock_host(struct ide_host *host, ide_hwif_t *hwif)
689 if (host->host_flags & IDE_HFLAG_SERIALIZE) {
690 rc = test_and_set_bit_lock(IDE_HOST_BUSY, &host->host_busy);
693 ide_get_lock(ide_intr, hwif);
699 static inline void ide_unlock_host(struct ide_host *host)
701 if (host->host_flags & IDE_HFLAG_SERIALIZE) {
704 clear_bit_unlock(IDE_HOST_BUSY, &host->host_busy);
709 * Issue a new request to a device.
711 void do_ide_request(struct request_queue *q)
713 ide_drive_t *drive = q->queuedata;
714 ide_hwif_t *hwif = drive->hwif;
715 struct ide_host *host = hwif->host;
716 struct request *rq = NULL;
717 ide_startstop_t startstop;
720 * drive is doing pre-flush, ordered write, post-flush sequence. even
721 * though that is 3 requests, it must be seen as a single transaction.
722 * we must not preempt this drive until that is complete
724 if (blk_queue_flushing(q))
726 * small race where queue could get replugged during
727 * the 3-request flush cycle, just yank the plug since
728 * we want it to finish asap
732 spin_unlock_irq(q->queue_lock);
734 if (ide_lock_host(host, hwif))
737 spin_lock_irq(&hwif->lock);
739 if (!ide_lock_port(hwif)) {
740 ide_hwif_t *prev_port;
742 prev_port = hwif->host->cur_port;
745 if (drive->dev_flags & IDE_DFLAG_SLEEPING) {
746 if (time_before(drive->sleep, jiffies)) {
747 ide_unlock_port(hwif);
752 if ((hwif->host->host_flags & IDE_HFLAG_SERIALIZE) &&
755 * set nIEN for previous port, drives in the
756 * quirk_list may not like intr setups/cleanups
758 if (prev_port && prev_port->cur_dev->quirk_list == 0)
759 prev_port->tp_ops->set_irq(prev_port, 0);
761 hwif->host->cur_port = hwif;
763 hwif->cur_dev = drive;
764 drive->dev_flags &= ~(IDE_DFLAG_SLEEPING | IDE_DFLAG_PARKED);
766 spin_unlock_irq(&hwif->lock);
767 spin_lock_irq(q->queue_lock);
769 * we know that the queue isn't empty, but this can happen
770 * if the q->prep_rq_fn() decides to kill a request
772 rq = elv_next_request(drive->queue);
773 spin_unlock_irq(q->queue_lock);
774 spin_lock_irq(&hwif->lock);
777 ide_unlock_port(hwif);
782 * Sanity: don't accept a request that isn't a PM request
783 * if we are currently power managed. This is very important as
784 * blk_stop_queue() doesn't prevent the elv_next_request()
785 * above to return us whatever is in the queue. Since we call
786 * ide_do_request() ourselves, we end up taking requests while
787 * the queue is blocked...
789 * We let requests forced at head of queue with ide-preempt
790 * though. I hope that doesn't happen too much, hopefully not
791 * unless the subdriver triggers such a thing in its own PM
794 if ((drive->dev_flags & IDE_DFLAG_BLOCKED) &&
795 blk_pm_request(rq) == 0 &&
796 (rq->cmd_flags & REQ_PREEMPT) == 0) {
797 /* there should be no pending command at this point */
798 ide_unlock_port(hwif);
804 spin_unlock_irq(&hwif->lock);
805 startstop = start_request(drive, rq);
806 spin_lock_irq(&hwif->lock);
808 if (startstop == ide_stopped)
813 spin_unlock_irq(&hwif->lock);
815 ide_unlock_host(host);
816 spin_lock_irq(q->queue_lock);
820 spin_unlock_irq(&hwif->lock);
821 ide_unlock_host(host);
823 spin_lock_irq(q->queue_lock);
825 if (!elv_queue_empty(q))
830 * un-busy the port etc, and clear any pending DMA status. we want to
831 * retry the current request in pio mode instead of risking tossing it
834 static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
836 ide_hwif_t *hwif = HWIF(drive);
838 ide_startstop_t ret = ide_stopped;
841 * end current dma transaction
845 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
846 (void)hwif->dma_ops->dma_end(drive);
847 ret = ide_error(drive, "dma timeout error",
848 hwif->tp_ops->read_status(hwif));
850 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
851 hwif->dma_ops->dma_timeout(drive);
855 * disable dma for now, but remember that we did so because of
856 * a timeout -- we'll reenable after we finish this next request
857 * (or rather the first chunk of it) in pio.
859 drive->dev_flags |= IDE_DFLAG_DMA_PIO_RETRY;
861 ide_dma_off_quietly(drive);
864 * un-busy drive etc and make sure request is sane
878 rq->sector = rq->bio->bi_sector;
879 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
880 rq->hard_cur_sectors = rq->current_nr_sectors;
881 rq->buffer = bio_data(rq->bio);
886 static void ide_plug_device(ide_drive_t *drive)
888 struct request_queue *q = drive->queue;
891 spin_lock_irqsave(q->queue_lock, flags);
892 if (!elv_queue_empty(q))
894 spin_unlock_irqrestore(q->queue_lock, flags);
898 * ide_timer_expiry - handle lack of an IDE interrupt
899 * @data: timer callback magic (hwif)
901 * An IDE command has timed out before the expected drive return
902 * occurred. At this point we attempt to clean up the current
903 * mess. If the current handler includes an expiry handler then
904 * we invoke the expiry handler, and providing it is happy the
905 * work is done. If that fails we apply generic recovery rules
906 * invoking the handler and checking the drive DMA status. We
907 * have an excessively incestuous relationship with the DMA
908 * logic that wants cleaning up.
911 void ide_timer_expiry (unsigned long data)
913 ide_hwif_t *hwif = (ide_hwif_t *)data;
914 ide_drive_t *uninitialized_var(drive);
915 ide_handler_t *handler;
917 unsigned long wait = -1;
920 spin_lock_irqsave(&hwif->lock, flags);
922 handler = hwif->handler;
924 if (handler == NULL || hwif->req_gen != hwif->req_gen_timer) {
926 * Either a marginal timeout occurred
927 * (got the interrupt just as timer expired),
928 * or we were "sleeping" to give other devices a chance.
929 * Either way, we don't really want to complain about anything.
932 drive = hwif->cur_dev;
934 printk(KERN_ERR "%s: ->cur_dev was NULL\n", __func__);
935 hwif->handler = NULL;
937 ide_expiry_t *expiry = hwif->expiry;
938 ide_startstop_t startstop = ide_stopped;
942 if ((wait = expiry(drive)) > 0) {
944 hwif->timer.expires = jiffies + wait;
945 hwif->req_gen_timer = hwif->req_gen;
946 add_timer(&hwif->timer);
947 spin_unlock_irqrestore(&hwif->lock, flags);
951 hwif->handler = NULL;
953 * We need to simulate a real interrupt when invoking
954 * the handler() function, which means we need to
955 * globally mask the specific IRQ:
957 spin_unlock(&hwif->lock);
959 /* disable_irq_nosync ?? */
960 disable_irq(hwif->irq);
962 * as if we were handling an interrupt */
965 startstop = handler(drive);
966 } else if (drive_is_ready(drive)) {
967 if (drive->waiting_for_dma)
968 hwif->dma_ops->dma_lost_irq(drive);
969 (void)ide_ack_intr(hwif);
970 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
971 startstop = handler(drive);
973 if (drive->waiting_for_dma) {
974 startstop = ide_dma_timeout_retry(drive, wait);
977 ide_error(drive, "irq timeout",
978 hwif->tp_ops->read_status(hwif));
980 spin_lock_irq(&hwif->lock);
981 enable_irq(hwif->irq);
982 if (startstop == ide_stopped) {
983 ide_unlock_port(hwif);
988 spin_unlock_irqrestore(&hwif->lock, flags);
991 ide_unlock_host(hwif->host);
992 ide_plug_device(drive);
997 * unexpected_intr - handle an unexpected IDE interrupt
998 * @irq: interrupt line
999 * @hwif: port being processed
1001 * There's nothing really useful we can do with an unexpected interrupt,
1002 * other than reading the status register (to clear it), and logging it.
1003 * There should be no way that an irq can happen before we're ready for it,
1004 * so we needn't worry much about losing an "important" interrupt here.
1006 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1007 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1008 * looks "good", we just ignore the interrupt completely.
1010 * This routine assumes __cli() is in effect when called.
1012 * If an unexpected interrupt happens on irq15 while we are handling irq14
1013 * and if the two interfaces are "serialized" (CMD640), then it looks like
1014 * we could screw up by interfering with a new request being set up for
1017 * In reality, this is a non-issue. The new command is not sent unless
1018 * the drive is ready to accept one, in which case we know the drive is
1019 * not trying to interrupt us. And ide_set_handler() is always invoked
1020 * before completing the issuance of any new drive command, so we will not
1021 * be accidentally invoked as a result of any valid command completion
1025 static void unexpected_intr(int irq, ide_hwif_t *hwif)
1027 u8 stat = hwif->tp_ops->read_status(hwif);
1029 if (!OK_STAT(stat, ATA_DRDY, BAD_STAT)) {
1030 /* Try to not flood the console with msgs */
1031 static unsigned long last_msgtime, count;
1034 if (time_after(jiffies, last_msgtime + HZ)) {
1035 last_msgtime = jiffies;
1036 printk(KERN_ERR "%s: unexpected interrupt, "
1037 "status=0x%02x, count=%ld\n",
1038 hwif->name, stat, count);
1044 * ide_intr - default IDE interrupt handler
1045 * @irq: interrupt number
1047 * @regs: unused weirdness from the kernel irq layer
1049 * This is the default IRQ handler for the IDE layer. You should
1050 * not need to override it. If you do be aware it is subtle in
1053 * hwif is the interface in the group currently performing
1054 * a command. hwif->cur_dev is the drive and hwif->handler is
1055 * the IRQ handler to call. As we issue a command the handlers
1056 * step through multiple states, reassigning the handler to the
1057 * next step in the process. Unlike a smart SCSI controller IDE
1058 * expects the main processor to sequence the various transfer
1059 * stages. We also manage a poll timer to catch up with most
1060 * timeout situations. There are still a few where the handlers
1061 * don't ever decide to give up.
1063 * The handler eventually returns ide_stopped to indicate the
1064 * request completed. At this point we issue the next request
1065 * on the port and the process begins again.
1068 irqreturn_t ide_intr (int irq, void *dev_id)
1070 ide_hwif_t *hwif = (ide_hwif_t *)dev_id;
1071 ide_drive_t *uninitialized_var(drive);
1072 ide_handler_t *handler;
1073 unsigned long flags;
1074 ide_startstop_t startstop;
1075 irqreturn_t irq_ret = IRQ_NONE;
1076 int plug_device = 0;
1078 if (hwif->host->host_flags & IDE_HFLAG_SERIALIZE) {
1079 if (hwif != hwif->host->cur_port)
1083 spin_lock_irqsave(&hwif->lock, flags);
1085 if (!ide_ack_intr(hwif))
1088 handler = hwif->handler;
1090 if (handler == NULL || hwif->polling) {
1092 * Not expecting an interrupt from this drive.
1093 * That means this could be:
1094 * (1) an interrupt from another PCI device
1095 * sharing the same PCI INT# as us.
1096 * or (2) a drive just entered sleep or standby mode,
1097 * and is interrupting to let us know.
1098 * or (3) a spurious interrupt of unknown origin.
1100 * For PCI, we cannot tell the difference,
1101 * so in that case we just ignore it and hope it goes away.
1103 * FIXME: unexpected_intr should be hwif-> then we can
1104 * remove all the ifdef PCI crap
1106 #ifdef CONFIG_BLK_DEV_IDEPCI
1107 if (hwif->chipset != ide_pci)
1108 #endif /* CONFIG_BLK_DEV_IDEPCI */
1111 * Probably not a shared PCI interrupt,
1112 * so we can safely try to do something about it:
1114 unexpected_intr(irq, hwif);
1115 #ifdef CONFIG_BLK_DEV_IDEPCI
1118 * Whack the status register, just in case
1119 * we have a leftover pending IRQ.
1121 (void)hwif->tp_ops->read_status(hwif);
1122 #endif /* CONFIG_BLK_DEV_IDEPCI */
1127 drive = hwif->cur_dev;
1130 * This should NEVER happen, and there isn't much
1131 * we could do about it here.
1133 * [Note - this can occur if the drive is hot unplugged]
1138 if (!drive_is_ready(drive))
1140 * This happens regularly when we share a PCI IRQ with
1141 * another device. Unfortunately, it can also happen
1142 * with some buggy drives that trigger the IRQ before
1143 * their status register is up to date. Hopefully we have
1144 * enough advance overhead that the latter isn't a problem.
1148 hwif->handler = NULL;
1150 del_timer(&hwif->timer);
1151 spin_unlock(&hwif->lock);
1153 if (hwif->port_ops && hwif->port_ops->clear_irq)
1154 hwif->port_ops->clear_irq(drive);
1156 if (drive->dev_flags & IDE_DFLAG_UNMASK)
1157 local_irq_enable_in_hardirq();
1159 /* service this interrupt, may set handler for next interrupt */
1160 startstop = handler(drive);
1162 spin_lock_irq(&hwif->lock);
1164 * Note that handler() may have set things up for another
1165 * interrupt to occur soon, but it cannot happen until
1166 * we exit from this routine, because it will be the
1167 * same irq as is currently being serviced here, and Linux
1168 * won't allow another of the same (on any CPU) until we return.
1170 if (startstop == ide_stopped) {
1171 if (hwif->handler == NULL) { /* paranoia */
1172 ide_unlock_port(hwif);
1175 printk(KERN_ERR "%s: %s: huh? expected NULL handler "
1176 "on exit\n", __func__, drive->name);
1179 irq_ret = IRQ_HANDLED;
1181 spin_unlock_irqrestore(&hwif->lock, flags);
1184 ide_unlock_host(hwif->host);
1185 ide_plug_device(drive);
1192 * ide_do_drive_cmd - issue IDE special command
1193 * @drive: device to issue command
1194 * @rq: request to issue
1196 * This function issues a special IDE device request
1197 * onto the request queue.
1199 * the rq is queued at the head of the request queue, displacing
1200 * the currently-being-processed request and this function
1201 * returns immediately without waiting for the new rq to be
1202 * completed. This is VERY DANGEROUS, and is intended for
1203 * careful use by the ATAPI tape/cdrom driver code.
1206 void ide_do_drive_cmd(ide_drive_t *drive, struct request *rq)
1208 struct request_queue *q = drive->queue;
1209 unsigned long flags;
1211 drive->hwif->rq = NULL;
1213 spin_lock_irqsave(q->queue_lock, flags);
1214 __elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
1215 spin_unlock_irqrestore(q->queue_lock, flags);
1217 EXPORT_SYMBOL(ide_do_drive_cmd);
1219 void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma)
1221 ide_hwif_t *hwif = drive->hwif;
1224 memset(&task, 0, sizeof(task));
1225 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM |
1226 IDE_TFLAG_OUT_FEATURE | tf_flags;
1227 task.tf.feature = dma; /* Use PIO/DMA */
1228 task.tf.lbam = bcount & 0xff;
1229 task.tf.lbah = (bcount >> 8) & 0xff;
1231 ide_tf_dump(drive->name, &task.tf);
1232 hwif->tp_ops->set_irq(hwif, 1);
1233 SELECT_MASK(drive, 0);
1234 hwif->tp_ops->tf_load(drive, &task);
1237 EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load);
1239 void ide_pad_transfer(ide_drive_t *drive, int write, int len)
1241 ide_hwif_t *hwif = drive->hwif;
1246 hwif->tp_ops->output_data(drive, NULL, buf, min(4, len));
1248 hwif->tp_ops->input_data(drive, NULL, buf, min(4, len));
1252 EXPORT_SYMBOL_GPL(ide_pad_transfer);