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)
202 struct ide_driver *drv;
204 drv = *(struct ide_driver **)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);
294 static ide_startstop_t
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);
303 * ide_error - handle an error on the IDE
304 * @drive: drive the error occurred on
305 * @msg: message to report
308 * ide_error() takes action based on the error returned by the drive.
309 * For normal I/O that may well include retries. We deal with
310 * both new-style (taskfile) and old style command handling here.
311 * In the case of taskfile command handling there is work left to
315 ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
320 err = ide_dump_status(drive, msg, stat);
322 rq = drive->hwif->rq;
326 /* retry only "normal" I/O: */
327 if (!blk_fs_request(rq)) {
329 ide_end_drive_cmd(drive, stat, err);
333 return __ide_error(drive, rq, stat, err);
335 EXPORT_SYMBOL_GPL(ide_error);
337 static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
339 tf->nsect = drive->sect;
340 tf->lbal = drive->sect;
341 tf->lbam = drive->cyl;
342 tf->lbah = drive->cyl >> 8;
343 tf->device = (drive->head - 1) | drive->select;
344 tf->command = ATA_CMD_INIT_DEV_PARAMS;
347 static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
349 tf->nsect = drive->sect;
350 tf->command = ATA_CMD_RESTORE;
353 static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
355 tf->nsect = drive->mult_req;
356 tf->command = ATA_CMD_SET_MULTI;
359 static ide_startstop_t ide_disk_special(ide_drive_t *drive)
361 special_t *s = &drive->special;
364 memset(&args, 0, sizeof(ide_task_t));
365 args.data_phase = TASKFILE_NO_DATA;
367 if (s->b.set_geometry) {
368 s->b.set_geometry = 0;
369 ide_tf_set_specify_cmd(drive, &args.tf);
370 } else if (s->b.recalibrate) {
371 s->b.recalibrate = 0;
372 ide_tf_set_restore_cmd(drive, &args.tf);
373 } else if (s->b.set_multmode) {
374 s->b.set_multmode = 0;
375 ide_tf_set_setmult_cmd(drive, &args.tf);
377 int special = s->all;
379 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
383 args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE |
384 IDE_TFLAG_CUSTOM_HANDLER;
386 do_rw_taskfile(drive, &args);
392 * do_special - issue some special commands
393 * @drive: drive the command is for
395 * do_special() is used to issue ATA_CMD_INIT_DEV_PARAMS,
396 * ATA_CMD_RESTORE and ATA_CMD_SET_MULTI commands to a drive.
398 * It used to do much more, but has been scaled back.
401 static ide_startstop_t do_special (ide_drive_t *drive)
403 special_t *s = &drive->special;
406 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
408 if (drive->media == ide_disk)
409 return ide_disk_special(drive);
416 void ide_map_sg(ide_drive_t *drive, struct request *rq)
418 ide_hwif_t *hwif = drive->hwif;
419 struct scatterlist *sg = hwif->sg_table;
421 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
422 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
424 } else if (!rq->bio) {
425 sg_init_one(sg, rq->data, rq->data_len);
428 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
432 EXPORT_SYMBOL_GPL(ide_map_sg);
434 void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
436 ide_hwif_t *hwif = drive->hwif;
438 hwif->nsect = hwif->nleft = rq->nr_sectors;
443 EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
446 * execute_drive_command - issue special drive command
447 * @drive: the drive to issue the command on
448 * @rq: the request structure holding the command
450 * execute_drive_cmd() issues a special drive command, usually
451 * initiated by ioctl() from the external hdparm program. The
452 * command can be a drive command, drive task or taskfile
453 * operation. Weirdly you can call it with NULL to wait for
454 * all commands to finish. Don't do this as that is due to change
457 static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
460 ide_hwif_t *hwif = drive->hwif;
461 ide_task_t *task = rq->special;
464 hwif->data_phase = task->data_phase;
466 switch (hwif->data_phase) {
467 case TASKFILE_MULTI_OUT:
469 case TASKFILE_MULTI_IN:
471 ide_init_sg_cmd(drive, rq);
472 ide_map_sg(drive, rq);
477 return do_rw_taskfile(drive, task);
481 * NULL is actually a valid way of waiting for
482 * all current requests to be flushed from the queue.
485 printk("%s: DRIVE_CMD (null)\n", drive->name);
487 ide_end_drive_cmd(drive, hwif->tp_ops->read_status(hwif),
488 ide_read_error(drive));
493 int ide_devset_execute(ide_drive_t *drive, const struct ide_devset *setting,
496 struct request_queue *q = drive->queue;
500 if (!(setting->flags & DS_SYNC))
501 return setting->set(drive, arg);
503 rq = blk_get_request(q, READ, __GFP_WAIT);
504 rq->cmd_type = REQ_TYPE_SPECIAL;
506 rq->cmd[0] = REQ_DEVSET_EXEC;
507 *(int *)&rq->cmd[1] = arg;
508 rq->special = setting->set;
510 if (blk_execute_rq(q, NULL, rq, 0))
517 static ide_startstop_t ide_do_devset(ide_drive_t *drive, struct request *rq)
519 int err, (*setfunc)(ide_drive_t *, int) = rq->special;
521 err = setfunc(drive, *(int *)&rq->cmd[1]);
526 ide_end_request(drive, err, 0);
530 static ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
533 struct ide_taskfile *tf = &task.tf;
535 memset(&task, 0, sizeof(task));
536 if (rq->cmd[0] == REQ_PARK_HEADS) {
537 drive->sleep = *(unsigned long *)rq->special;
538 drive->dev_flags |= IDE_DFLAG_SLEEPING;
539 tf->command = ATA_CMD_IDLEIMMEDIATE;
544 task.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
545 } else /* cmd == REQ_UNPARK_HEADS */
546 tf->command = ATA_CMD_CHK_POWER;
548 task.tf_flags |= IDE_TFLAG_TF | IDE_TFLAG_DEVICE;
550 drive->hwif->data_phase = task.data_phase = TASKFILE_NO_DATA;
551 return do_rw_taskfile(drive, &task);
554 static ide_startstop_t ide_special_rq(ide_drive_t *drive, struct request *rq)
560 case REQ_UNPARK_HEADS:
561 return ide_do_park_unpark(drive, rq);
562 case REQ_DEVSET_EXEC:
563 return ide_do_devset(drive, rq);
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 drive->hwif->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) {
609 struct ide_driver *drv;
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 = *(struct ide_driver **)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))
829 static void ide_plug_device(ide_drive_t *drive)
831 struct request_queue *q = drive->queue;
834 spin_lock_irqsave(q->queue_lock, flags);
835 if (!elv_queue_empty(q))
837 spin_unlock_irqrestore(q->queue_lock, flags);
840 static int drive_is_ready(ide_drive_t *drive)
842 ide_hwif_t *hwif = drive->hwif;
845 if (drive->waiting_for_dma)
846 return hwif->dma_ops->dma_test_irq(drive);
848 if (hwif->io_ports.ctl_addr &&
849 (hwif->host_flags & IDE_HFLAG_BROKEN_ALTSTATUS) == 0)
850 stat = hwif->tp_ops->read_altstatus(hwif);
852 /* Note: this may clear a pending IRQ!! */
853 stat = hwif->tp_ops->read_status(hwif);
856 /* drive busy: definitely not interrupting */
859 /* drive ready: *might* be interrupting */
864 * ide_timer_expiry - handle lack of an IDE interrupt
865 * @data: timer callback magic (hwif)
867 * An IDE command has timed out before the expected drive return
868 * occurred. At this point we attempt to clean up the current
869 * mess. If the current handler includes an expiry handler then
870 * we invoke the expiry handler, and providing it is happy the
871 * work is done. If that fails we apply generic recovery rules
872 * invoking the handler and checking the drive DMA status. We
873 * have an excessively incestuous relationship with the DMA
874 * logic that wants cleaning up.
877 void ide_timer_expiry (unsigned long data)
879 ide_hwif_t *hwif = (ide_hwif_t *)data;
880 ide_drive_t *uninitialized_var(drive);
881 ide_handler_t *handler;
886 spin_lock_irqsave(&hwif->lock, flags);
888 handler = hwif->handler;
890 if (handler == NULL || hwif->req_gen != hwif->req_gen_timer) {
892 * Either a marginal timeout occurred
893 * (got the interrupt just as timer expired),
894 * or we were "sleeping" to give other devices a chance.
895 * Either way, we don't really want to complain about anything.
898 ide_expiry_t *expiry = hwif->expiry;
899 ide_startstop_t startstop = ide_stopped;
901 drive = hwif->cur_dev;
904 wait = expiry(drive);
905 if (wait > 0) { /* continue */
907 hwif->timer.expires = jiffies + wait;
908 hwif->req_gen_timer = hwif->req_gen;
909 add_timer(&hwif->timer);
910 spin_unlock_irqrestore(&hwif->lock, flags);
914 hwif->handler = NULL;
916 * We need to simulate a real interrupt when invoking
917 * the handler() function, which means we need to
918 * globally mask the specific IRQ:
920 spin_unlock(&hwif->lock);
921 /* disable_irq_nosync ?? */
922 disable_irq(hwif->irq);
923 /* local CPU only, as if we were handling an interrupt */
926 startstop = handler(drive);
927 } else if (drive_is_ready(drive)) {
928 if (drive->waiting_for_dma)
929 hwif->dma_ops->dma_lost_irq(drive);
930 (void)ide_ack_intr(hwif);
931 printk(KERN_WARNING "%s: lost interrupt\n",
933 startstop = handler(drive);
935 if (drive->waiting_for_dma)
936 startstop = ide_dma_timeout_retry(drive, wait);
938 startstop = ide_error(drive, "irq timeout",
939 hwif->tp_ops->read_status(hwif));
941 spin_lock_irq(&hwif->lock);
942 enable_irq(hwif->irq);
943 if (startstop == ide_stopped) {
944 ide_unlock_port(hwif);
948 spin_unlock_irqrestore(&hwif->lock, flags);
951 ide_unlock_host(hwif->host);
952 ide_plug_device(drive);
957 * unexpected_intr - handle an unexpected IDE interrupt
958 * @irq: interrupt line
959 * @hwif: port being processed
961 * There's nothing really useful we can do with an unexpected interrupt,
962 * other than reading the status register (to clear it), and logging it.
963 * There should be no way that an irq can happen before we're ready for it,
964 * so we needn't worry much about losing an "important" interrupt here.
966 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
967 * the drive enters "idle", "standby", or "sleep" mode, so if the status
968 * looks "good", we just ignore the interrupt completely.
970 * This routine assumes __cli() is in effect when called.
972 * If an unexpected interrupt happens on irq15 while we are handling irq14
973 * and if the two interfaces are "serialized" (CMD640), then it looks like
974 * we could screw up by interfering with a new request being set up for
977 * In reality, this is a non-issue. The new command is not sent unless
978 * the drive is ready to accept one, in which case we know the drive is
979 * not trying to interrupt us. And ide_set_handler() is always invoked
980 * before completing the issuance of any new drive command, so we will not
981 * be accidentally invoked as a result of any valid command completion
985 static void unexpected_intr(int irq, ide_hwif_t *hwif)
987 u8 stat = hwif->tp_ops->read_status(hwif);
989 if (!OK_STAT(stat, ATA_DRDY, BAD_STAT)) {
990 /* Try to not flood the console with msgs */
991 static unsigned long last_msgtime, count;
994 if (time_after(jiffies, last_msgtime + HZ)) {
995 last_msgtime = jiffies;
996 printk(KERN_ERR "%s: unexpected interrupt, "
997 "status=0x%02x, count=%ld\n",
998 hwif->name, stat, count);
1004 * ide_intr - default IDE interrupt handler
1005 * @irq: interrupt number
1007 * @regs: unused weirdness from the kernel irq layer
1009 * This is the default IRQ handler for the IDE layer. You should
1010 * not need to override it. If you do be aware it is subtle in
1013 * hwif is the interface in the group currently performing
1014 * a command. hwif->cur_dev is the drive and hwif->handler is
1015 * the IRQ handler to call. As we issue a command the handlers
1016 * step through multiple states, reassigning the handler to the
1017 * next step in the process. Unlike a smart SCSI controller IDE
1018 * expects the main processor to sequence the various transfer
1019 * stages. We also manage a poll timer to catch up with most
1020 * timeout situations. There are still a few where the handlers
1021 * don't ever decide to give up.
1023 * The handler eventually returns ide_stopped to indicate the
1024 * request completed. At this point we issue the next request
1025 * on the port and the process begins again.
1028 irqreturn_t ide_intr (int irq, void *dev_id)
1030 ide_hwif_t *hwif = (ide_hwif_t *)dev_id;
1031 ide_drive_t *uninitialized_var(drive);
1032 ide_handler_t *handler;
1033 unsigned long flags;
1034 ide_startstop_t startstop;
1035 irqreturn_t irq_ret = IRQ_NONE;
1036 int plug_device = 0;
1038 if (hwif->host->host_flags & IDE_HFLAG_SERIALIZE) {
1039 if (hwif != hwif->host->cur_port)
1043 spin_lock_irqsave(&hwif->lock, flags);
1045 if (!ide_ack_intr(hwif))
1048 handler = hwif->handler;
1050 if (handler == NULL || hwif->polling) {
1052 * Not expecting an interrupt from this drive.
1053 * That means this could be:
1054 * (1) an interrupt from another PCI device
1055 * sharing the same PCI INT# as us.
1056 * or (2) a drive just entered sleep or standby mode,
1057 * and is interrupting to let us know.
1058 * or (3) a spurious interrupt of unknown origin.
1060 * For PCI, we cannot tell the difference,
1061 * so in that case we just ignore it and hope it goes away.
1063 * FIXME: unexpected_intr should be hwif-> then we can
1064 * remove all the ifdef PCI crap
1066 #ifdef CONFIG_BLK_DEV_IDEPCI
1067 if (hwif->chipset != ide_pci)
1068 #endif /* CONFIG_BLK_DEV_IDEPCI */
1071 * Probably not a shared PCI interrupt,
1072 * so we can safely try to do something about it:
1074 unexpected_intr(irq, hwif);
1075 #ifdef CONFIG_BLK_DEV_IDEPCI
1078 * Whack the status register, just in case
1079 * we have a leftover pending IRQ.
1081 (void)hwif->tp_ops->read_status(hwif);
1082 #endif /* CONFIG_BLK_DEV_IDEPCI */
1087 drive = hwif->cur_dev;
1089 if (!drive_is_ready(drive))
1091 * This happens regularly when we share a PCI IRQ with
1092 * another device. Unfortunately, it can also happen
1093 * with some buggy drives that trigger the IRQ before
1094 * their status register is up to date. Hopefully we have
1095 * enough advance overhead that the latter isn't a problem.
1099 hwif->handler = NULL;
1101 del_timer(&hwif->timer);
1102 spin_unlock(&hwif->lock);
1104 if (hwif->port_ops && hwif->port_ops->clear_irq)
1105 hwif->port_ops->clear_irq(drive);
1107 if (drive->dev_flags & IDE_DFLAG_UNMASK)
1108 local_irq_enable_in_hardirq();
1110 /* service this interrupt, may set handler for next interrupt */
1111 startstop = handler(drive);
1113 spin_lock_irq(&hwif->lock);
1115 * Note that handler() may have set things up for another
1116 * interrupt to occur soon, but it cannot happen until
1117 * we exit from this routine, because it will be the
1118 * same irq as is currently being serviced here, and Linux
1119 * won't allow another of the same (on any CPU) until we return.
1121 if (startstop == ide_stopped) {
1122 BUG_ON(hwif->handler);
1123 ide_unlock_port(hwif);
1126 irq_ret = IRQ_HANDLED;
1128 spin_unlock_irqrestore(&hwif->lock, flags);
1131 ide_unlock_host(hwif->host);
1132 ide_plug_device(drive);
1137 EXPORT_SYMBOL_GPL(ide_intr);
1139 void ide_pad_transfer(ide_drive_t *drive, int write, int len)
1141 ide_hwif_t *hwif = drive->hwif;
1146 hwif->tp_ops->output_data(drive, NULL, buf, min(4, len));
1148 hwif->tp_ops->input_data(drive, NULL, buf, min(4, len));
1152 EXPORT_SYMBOL_GPL(ide_pad_transfer);