2 * linux/drivers/ide/ide-taskfile.c Version 0.38 March 05, 2003
4 * Copyright (C) 2000-2002 Michael Cornwell <cornwell@acm.org>
5 * Copyright (C) 2000-2002 Andre Hedrick <andre@linux-ide.org>
6 * Copyright (C) 2001-2002 Klaus Smolin
7 * IBM Storage Technology Division
8 * Copyright (C) 2003-2004 Bartlomiej Zolnierkiewicz
10 * The big the bad and the ugly.
12 * Problems to be fixed because of BH interface or the lack therefore.
14 * Fill me in stupid !!!
17 * General refers to the Controller and Driver "pair".
19 * Under the context of Linux it generally refers to an interrupt handler.
20 * However, it correctly describes the 'HOST'
22 * The amount of data needed to be transfered as predefined in the
23 * setup of the device.
25 * The 'DATA BLOCK' associated to the 'DATA HANDLER', and can be as
26 * small as a single sector or as large as the entire command block
30 #include <linux/config.h>
31 #include <linux/module.h>
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/kernel.h>
35 #include <linux/timer.h>
37 #include <linux/sched.h>
38 #include <linux/interrupt.h>
39 #include <linux/major.h>
40 #include <linux/errno.h>
41 #include <linux/genhd.h>
42 #include <linux/blkpg.h>
43 #include <linux/slab.h>
44 #include <linux/pci.h>
45 #include <linux/delay.h>
46 #include <linux/hdreg.h>
47 #include <linux/ide.h>
48 #include <linux/bitops.h>
50 #include <asm/byteorder.h>
52 #include <asm/uaccess.h>
55 static void ata_bswap_data (void *buffer, int wcount)
60 *p = *p << 8 | *p >> 8; p++;
61 *p = *p << 8 | *p >> 8; p++;
65 static void taskfile_input_data(ide_drive_t *drive, void *buffer, u32 wcount)
67 HWIF(drive)->ata_input_data(drive, buffer, wcount);
69 ata_bswap_data(buffer, wcount);
72 static void taskfile_output_data(ide_drive_t *drive, void *buffer, u32 wcount)
75 ata_bswap_data(buffer, wcount);
76 HWIF(drive)->ata_output_data(drive, buffer, wcount);
77 ata_bswap_data(buffer, wcount);
79 HWIF(drive)->ata_output_data(drive, buffer, wcount);
83 int taskfile_lib_get_identify (ide_drive_t *drive, u8 *buf)
86 memset(&args, 0, sizeof(ide_task_t));
87 args.tfRegister[IDE_NSECTOR_OFFSET] = 0x01;
88 if (drive->media == ide_disk)
89 args.tfRegister[IDE_COMMAND_OFFSET] = WIN_IDENTIFY;
91 args.tfRegister[IDE_COMMAND_OFFSET] = WIN_PIDENTIFY;
92 args.command_type = IDE_DRIVE_TASK_IN;
93 args.data_phase = TASKFILE_IN;
94 args.handler = &task_in_intr;
95 return ide_raw_taskfile(drive, &args, buf);
98 ide_startstop_t do_rw_taskfile (ide_drive_t *drive, ide_task_t *task)
100 ide_hwif_t *hwif = HWIF(drive);
101 task_struct_t *taskfile = (task_struct_t *) task->tfRegister;
102 hob_struct_t *hobfile = (hob_struct_t *) task->hobRegister;
103 u8 HIHI = (drive->addressing == 1) ? 0xE0 : 0xEF;
105 /* ALL Command Block Executions SHALL clear nIEN, unless otherwise */
106 if (IDE_CONTROL_REG) {
108 hwif->OUTB(drive->ctl, IDE_CONTROL_REG);
110 SELECT_MASK(drive, 0);
112 if (drive->addressing == 1) {
113 hwif->OUTB(hobfile->feature, IDE_FEATURE_REG);
114 hwif->OUTB(hobfile->sector_count, IDE_NSECTOR_REG);
115 hwif->OUTB(hobfile->sector_number, IDE_SECTOR_REG);
116 hwif->OUTB(hobfile->low_cylinder, IDE_LCYL_REG);
117 hwif->OUTB(hobfile->high_cylinder, IDE_HCYL_REG);
120 hwif->OUTB(taskfile->feature, IDE_FEATURE_REG);
121 hwif->OUTB(taskfile->sector_count, IDE_NSECTOR_REG);
122 hwif->OUTB(taskfile->sector_number, IDE_SECTOR_REG);
123 hwif->OUTB(taskfile->low_cylinder, IDE_LCYL_REG);
124 hwif->OUTB(taskfile->high_cylinder, IDE_HCYL_REG);
126 hwif->OUTB((taskfile->device_head & HIHI) | drive->select.all, IDE_SELECT_REG);
128 if (task->handler != NULL) {
129 if (task->prehandler != NULL) {
130 hwif->OUTBSYNC(drive, taskfile->command, IDE_COMMAND_REG);
131 ndelay(400); /* FIXME */
132 return task->prehandler(drive, task->rq);
134 ide_execute_command(drive, taskfile->command, task->handler, WAIT_WORSTCASE, NULL);
138 if (!drive->using_dma)
141 switch (taskfile->command) {
142 case WIN_WRITEDMA_ONCE:
144 case WIN_WRITEDMA_EXT:
145 case WIN_READDMA_ONCE:
147 case WIN_READDMA_EXT:
148 case WIN_IDENTIFY_DMA:
149 if (!hwif->dma_setup(drive)) {
150 hwif->dma_exec_cmd(drive, taskfile->command);
151 hwif->dma_start(drive);
156 if (task->handler == NULL)
164 * set_multmode_intr() is invoked on completion of a WIN_SETMULT cmd.
166 ide_startstop_t set_multmode_intr (ide_drive_t *drive)
168 ide_hwif_t *hwif = HWIF(drive);
171 if (OK_STAT(stat = hwif->INB(IDE_STATUS_REG),READY_STAT,BAD_STAT)) {
172 drive->mult_count = drive->mult_req;
174 drive->mult_req = drive->mult_count = 0;
175 drive->special.b.recalibrate = 1;
176 (void) ide_dump_status(drive, "set_multmode", stat);
182 * set_geometry_intr() is invoked on completion of a WIN_SPECIFY cmd.
184 ide_startstop_t set_geometry_intr (ide_drive_t *drive)
186 ide_hwif_t *hwif = HWIF(drive);
190 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
193 if (OK_STAT(stat, READY_STAT, BAD_STAT))
196 if (stat & (ERR_STAT|DRQ_STAT))
197 return ide_error(drive, "set_geometry_intr", stat);
199 if (HWGROUP(drive)->handler != NULL)
201 ide_set_handler(drive, &set_geometry_intr, WAIT_WORSTCASE, NULL);
206 * recal_intr() is invoked on completion of a WIN_RESTORE (recalibrate) cmd.
208 ide_startstop_t recal_intr (ide_drive_t *drive)
210 ide_hwif_t *hwif = HWIF(drive);
213 if (!OK_STAT(stat = hwif->INB(IDE_STATUS_REG), READY_STAT, BAD_STAT))
214 return ide_error(drive, "recal_intr", stat);
219 * Handler for commands without a data phase
221 ide_startstop_t task_no_data_intr (ide_drive_t *drive)
223 ide_task_t *args = HWGROUP(drive)->rq->special;
224 ide_hwif_t *hwif = HWIF(drive);
228 if (!OK_STAT(stat = hwif->INB(IDE_STATUS_REG),READY_STAT,BAD_STAT)) {
229 return ide_error(drive, "task_no_data_intr", stat);
230 /* calls ide_end_drive_cmd */
233 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
238 EXPORT_SYMBOL(task_no_data_intr);
240 static u8 wait_drive_not_busy(ide_drive_t *drive)
242 ide_hwif_t *hwif = HWIF(drive);
247 * Last sector was transfered, wait until drive is ready.
248 * This can take up to 10 usec, but we will wait max 1 ms
249 * (drive_cmd_intr() waits that long).
251 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
255 printk(KERN_ERR "%s: drive still BUSY!\n", drive->name);
260 static void ide_pio_sector(ide_drive_t *drive, unsigned int write)
262 ide_hwif_t *hwif = drive->hwif;
263 struct scatterlist *sg = hwif->sg_table;
265 #ifdef CONFIG_HIGHMEM
271 page = sg[hwif->cursg].page;
272 offset = sg[hwif->cursg].offset + hwif->cursg_ofs * SECTOR_SIZE;
274 /* get the current page and offset */
275 page = nth_page(page, (offset >> PAGE_SHIFT));
278 #ifdef CONFIG_HIGHMEM
279 local_irq_save(flags);
281 buf = kmap_atomic(page, KM_BIO_SRC_IRQ) + offset;
286 if ((hwif->cursg_ofs * SECTOR_SIZE) == sg[hwif->cursg].length) {
291 /* do the actual data transfer */
293 taskfile_output_data(drive, buf, SECTOR_WORDS);
295 taskfile_input_data(drive, buf, SECTOR_WORDS);
297 kunmap_atomic(buf, KM_BIO_SRC_IRQ);
298 #ifdef CONFIG_HIGHMEM
299 local_irq_restore(flags);
303 static void ide_pio_multi(ide_drive_t *drive, unsigned int write)
307 nsect = min_t(unsigned int, drive->hwif->nleft, drive->mult_count);
309 ide_pio_sector(drive, write);
312 static void ide_pio_datablock(ide_drive_t *drive, struct request *rq,
315 if (rq->bio) /* fs request */
318 touch_softlockup_watchdog();
320 switch (drive->hwif->data_phase) {
321 case TASKFILE_MULTI_IN:
322 case TASKFILE_MULTI_OUT:
323 ide_pio_multi(drive, write);
326 ide_pio_sector(drive, write);
331 static ide_startstop_t task_error(ide_drive_t *drive, struct request *rq,
332 const char *s, u8 stat)
335 ide_hwif_t *hwif = drive->hwif;
336 int sectors = hwif->nsect - hwif->nleft;
338 switch (hwif->data_phase) {
346 case TASKFILE_MULTI_IN:
350 case TASKFILE_MULTI_OUT:
351 sectors -= drive->mult_count;
359 drv = *(ide_driver_t **)rq->rq_disk->private_data;
360 drv->end_request(drive, 1, sectors);
363 return ide_error(drive, s, stat);
366 static void task_end_request(ide_drive_t *drive, struct request *rq, u8 stat)
368 if (rq->flags & REQ_DRIVE_TASKFILE) {
369 ide_task_t *task = rq->special;
371 if (task->tf_out_flags.all) {
372 u8 err = drive->hwif->INB(IDE_ERROR_REG);
373 ide_end_drive_cmd(drive, stat, err);
378 ide_end_request(drive, 1, rq->hard_nr_sectors);
382 * Handler for command with PIO data-in phase (Read/Read Multiple).
384 ide_startstop_t task_in_intr (ide_drive_t *drive)
386 ide_hwif_t *hwif = drive->hwif;
387 struct request *rq = HWGROUP(drive)->rq;
388 u8 stat = hwif->INB(IDE_STATUS_REG);
390 /* new way for dealing with premature shared PCI interrupts */
391 if (!OK_STAT(stat, DATA_READY, BAD_R_STAT)) {
392 if (stat & (ERR_STAT | DRQ_STAT))
393 return task_error(drive, rq, __FUNCTION__, stat);
394 /* No data yet, so wait for another IRQ. */
395 ide_set_handler(drive, &task_in_intr, WAIT_WORSTCASE, NULL);
399 ide_pio_datablock(drive, rq, 0);
401 /* If it was the last datablock check status and finish transfer. */
403 stat = wait_drive_not_busy(drive);
404 if (!OK_STAT(stat, 0, BAD_R_STAT))
405 return task_error(drive, rq, __FUNCTION__, stat);
406 task_end_request(drive, rq, stat);
410 /* Still data left to transfer. */
411 ide_set_handler(drive, &task_in_intr, WAIT_WORSTCASE, NULL);
415 EXPORT_SYMBOL(task_in_intr);
418 * Handler for command with PIO data-out phase (Write/Write Multiple).
420 static ide_startstop_t task_out_intr (ide_drive_t *drive)
422 ide_hwif_t *hwif = drive->hwif;
423 struct request *rq = HWGROUP(drive)->rq;
424 u8 stat = hwif->INB(IDE_STATUS_REG);
426 if (!OK_STAT(stat, DRIVE_READY, drive->bad_wstat))
427 return task_error(drive, rq, __FUNCTION__, stat);
429 /* Deal with unexpected ATA data phase. */
430 if (((stat & DRQ_STAT) == 0) ^ !hwif->nleft)
431 return task_error(drive, rq, __FUNCTION__, stat);
434 task_end_request(drive, rq, stat);
438 /* Still data left to transfer. */
439 ide_pio_datablock(drive, rq, 1);
440 ide_set_handler(drive, &task_out_intr, WAIT_WORSTCASE, NULL);
445 ide_startstop_t pre_task_out_intr (ide_drive_t *drive, struct request *rq)
447 ide_startstop_t startstop;
449 if (ide_wait_stat(&startstop, drive, DATA_READY,
450 drive->bad_wstat, WAIT_DRQ)) {
451 printk(KERN_ERR "%s: no DRQ after issuing %sWRITE%s\n",
453 drive->hwif->data_phase ? "MULT" : "",
454 drive->addressing ? "_EXT" : "");
461 ide_set_handler(drive, &task_out_intr, WAIT_WORSTCASE, NULL);
462 ide_pio_datablock(drive, rq, 1);
466 EXPORT_SYMBOL(pre_task_out_intr);
468 static int ide_diag_taskfile(ide_drive_t *drive, ide_task_t *args, unsigned long data_size, u8 *buf)
472 memset(&rq, 0, sizeof(rq));
473 rq.flags = REQ_DRIVE_TASKFILE;
477 * (ks) We transfer currently only whole sectors.
478 * This is suffient for now. But, it would be great,
479 * if we would find a solution to transfer any size.
480 * To support special commands like READ LONG.
482 if (args->command_type != IDE_DRIVE_TASK_NO_DATA) {
484 rq.nr_sectors = (args->hobRegister[IDE_NSECTOR_OFFSET] << 8) | args->tfRegister[IDE_NSECTOR_OFFSET];
486 rq.nr_sectors = data_size / SECTOR_SIZE;
488 if (!rq.nr_sectors) {
489 printk(KERN_ERR "%s: in/out command without data\n",
494 rq.hard_nr_sectors = rq.nr_sectors;
495 rq.hard_cur_sectors = rq.current_nr_sectors = rq.nr_sectors;
497 if (args->command_type == IDE_DRIVE_TASK_RAW_WRITE)
503 return ide_do_drive_cmd(drive, &rq, ide_wait);
506 int ide_raw_taskfile (ide_drive_t *drive, ide_task_t *args, u8 *buf)
508 return ide_diag_taskfile(drive, args, 0, buf);
511 EXPORT_SYMBOL(ide_raw_taskfile);
513 int ide_taskfile_ioctl (ide_drive_t *drive, unsigned int cmd, unsigned long arg)
515 ide_task_request_t *req_task;
519 task_ioreg_t *argsptr = args.tfRegister;
520 task_ioreg_t *hobsptr = args.hobRegister;
522 int tasksize = sizeof(struct ide_task_request_s);
525 u8 io_32bit = drive->io_32bit;
526 char __user *buf = (char __user *)arg;
528 // printk("IDE Taskfile ...\n");
530 req_task = kzalloc(tasksize, GFP_KERNEL);
531 if (req_task == NULL) return -ENOMEM;
532 if (copy_from_user(req_task, buf, tasksize)) {
537 taskout = (int) req_task->out_size;
538 taskin = (int) req_task->in_size;
541 int outtotal = tasksize;
542 outbuf = kzalloc(taskout, GFP_KERNEL);
543 if (outbuf == NULL) {
547 if (copy_from_user(outbuf, buf + outtotal, taskout)) {
554 int intotal = tasksize + taskout;
555 inbuf = kzalloc(taskin, GFP_KERNEL);
560 if (copy_from_user(inbuf, buf + intotal, taskin)) {
566 memset(&args, 0, sizeof(ide_task_t));
567 memcpy(argsptr, req_task->io_ports, HDIO_DRIVE_TASK_HDR_SIZE);
568 memcpy(hobsptr, req_task->hob_ports, HDIO_DRIVE_HOB_HDR_SIZE);
570 args.tf_in_flags = req_task->in_flags;
571 args.tf_out_flags = req_task->out_flags;
572 args.data_phase = req_task->data_phase;
573 args.command_type = req_task->req_cmd;
576 switch(req_task->data_phase) {
577 case TASKFILE_OUT_DMAQ:
578 case TASKFILE_OUT_DMA:
579 err = ide_diag_taskfile(drive, &args, taskout, outbuf);
581 case TASKFILE_IN_DMAQ:
582 case TASKFILE_IN_DMA:
583 err = ide_diag_taskfile(drive, &args, taskin, inbuf);
585 case TASKFILE_MULTI_OUT:
586 if (!drive->mult_count) {
587 /* (hs): give up if multcount is not set */
588 printk(KERN_ERR "%s: %s Multimode Write " \
589 "multcount is not set\n",
590 drive->name, __FUNCTION__);
596 args.prehandler = &pre_task_out_intr;
597 args.handler = &task_out_intr;
598 err = ide_diag_taskfile(drive, &args, taskout, outbuf);
600 case TASKFILE_MULTI_IN:
601 if (!drive->mult_count) {
602 /* (hs): give up if multcount is not set */
603 printk(KERN_ERR "%s: %s Multimode Read failure " \
604 "multcount is not set\n",
605 drive->name, __FUNCTION__);
611 args.handler = &task_in_intr;
612 err = ide_diag_taskfile(drive, &args, taskin, inbuf);
614 case TASKFILE_NO_DATA:
615 args.handler = &task_no_data_intr;
616 err = ide_diag_taskfile(drive, &args, 0, NULL);
623 memcpy(req_task->io_ports, &(args.tfRegister), HDIO_DRIVE_TASK_HDR_SIZE);
624 memcpy(req_task->hob_ports, &(args.hobRegister), HDIO_DRIVE_HOB_HDR_SIZE);
625 req_task->in_flags = args.tf_in_flags;
626 req_task->out_flags = args.tf_out_flags;
628 if (copy_to_user(buf, req_task, tasksize)) {
633 int outtotal = tasksize;
634 if (copy_to_user(buf + outtotal, outbuf, taskout)) {
640 int intotal = tasksize + taskout;
641 if (copy_to_user(buf + intotal, inbuf, taskin)) {
651 // printk("IDE Taskfile ioctl ended. rc = %i\n", err);
653 drive->io_32bit = io_32bit;
658 int ide_wait_cmd (ide_drive_t *drive, u8 cmd, u8 nsect, u8 feature, u8 sectors, u8 *buf)
665 memset(buf, 0, 4 + SECTOR_WORDS * 4 * sectors);
666 ide_init_drive_cmd(&rq);
672 return ide_do_drive_cmd(drive, &rq, ide_wait);
676 * FIXME : this needs to map into at taskfile. <andre@linux-ide.org>
678 int ide_cmd_ioctl (ide_drive_t *drive, unsigned int cmd, unsigned long arg)
681 u8 args[4], *argbuf = args;
686 if (NULL == (void *) arg) {
688 ide_init_drive_cmd(&rq);
689 return ide_do_drive_cmd(drive, &rq, ide_wait);
692 if (copy_from_user(args, (void __user *)arg, 4))
695 memset(&tfargs, 0, sizeof(ide_task_t));
696 tfargs.tfRegister[IDE_FEATURE_OFFSET] = args[2];
697 tfargs.tfRegister[IDE_NSECTOR_OFFSET] = args[3];
698 tfargs.tfRegister[IDE_SECTOR_OFFSET] = args[1];
699 tfargs.tfRegister[IDE_LCYL_OFFSET] = 0x00;
700 tfargs.tfRegister[IDE_HCYL_OFFSET] = 0x00;
701 tfargs.tfRegister[IDE_SELECT_OFFSET] = 0x00;
702 tfargs.tfRegister[IDE_COMMAND_OFFSET] = args[0];
705 argsize = 4 + (SECTOR_WORDS * 4 * args[3]);
706 argbuf = kzalloc(argsize, GFP_KERNEL);
710 if (set_transfer(drive, &tfargs)) {
712 if (ide_ata66_check(drive, &tfargs))
716 err = ide_wait_cmd(drive, args[0], args[1], args[2], args[3], argbuf);
718 if (!err && xfer_rate) {
719 /* active-retuning-calls future */
720 ide_set_xfer_rate(drive, xfer_rate);
721 ide_driveid_update(drive);
724 if (copy_to_user((void __user *)arg, argbuf, argsize))
731 static int ide_wait_cmd_task(ide_drive_t *drive, u8 *buf)
735 ide_init_drive_cmd(&rq);
736 rq.flags = REQ_DRIVE_TASK;
738 return ide_do_drive_cmd(drive, &rq, ide_wait);
742 * FIXME : this needs to map into at taskfile. <andre@linux-ide.org>
744 int ide_task_ioctl (ide_drive_t *drive, unsigned int cmd, unsigned long arg)
746 void __user *p = (void __user *)arg;
748 u8 args[7], *argbuf = args;
751 if (copy_from_user(args, p, 7))
753 err = ide_wait_cmd_task(drive, argbuf);
754 if (copy_to_user(p, argbuf, argsize))
760 * NOTICE: This is additions from IBM to provide a discrete interface,
761 * for selective taskregister access operations. Nice JOB Klaus!!!
762 * Glad to be able to work and co-develop this with you and IBM.
764 ide_startstop_t flagged_taskfile (ide_drive_t *drive, ide_task_t *task)
766 ide_hwif_t *hwif = HWIF(drive);
767 task_struct_t *taskfile = (task_struct_t *) task->tfRegister;
768 hob_struct_t *hobfile = (hob_struct_t *) task->hobRegister;
770 if (task->data_phase == TASKFILE_MULTI_IN ||
771 task->data_phase == TASKFILE_MULTI_OUT) {
772 if (!drive->mult_count) {
773 printk(KERN_ERR "%s: multimode not set!\n", drive->name);
779 * (ks) Check taskfile in flags.
780 * If set, then execute as it is defined.
781 * If not set, then define default settings.
782 * The default values are:
783 * read all taskfile registers (except data)
784 * read the hob registers (sector, nsector, lcyl, hcyl)
786 if (task->tf_in_flags.all == 0) {
787 task->tf_in_flags.all = IDE_TASKFILE_STD_IN_FLAGS;
788 if (drive->addressing == 1)
789 task->tf_in_flags.all |= (IDE_HOB_STD_IN_FLAGS << 8);
792 /* ALL Command Block Executions SHALL clear nIEN, unless otherwise */
795 hwif->OUTB(drive->ctl, IDE_CONTROL_REG);
796 SELECT_MASK(drive, 0);
798 if (task->tf_out_flags.b.data) {
799 u16 data = taskfile->data + (hobfile->data << 8);
800 hwif->OUTW(data, IDE_DATA_REG);
803 /* (ks) send hob registers first */
804 if (task->tf_out_flags.b.nsector_hob)
805 hwif->OUTB(hobfile->sector_count, IDE_NSECTOR_REG);
806 if (task->tf_out_flags.b.sector_hob)
807 hwif->OUTB(hobfile->sector_number, IDE_SECTOR_REG);
808 if (task->tf_out_flags.b.lcyl_hob)
809 hwif->OUTB(hobfile->low_cylinder, IDE_LCYL_REG);
810 if (task->tf_out_flags.b.hcyl_hob)
811 hwif->OUTB(hobfile->high_cylinder, IDE_HCYL_REG);
813 /* (ks) Send now the standard registers */
814 if (task->tf_out_flags.b.error_feature)
815 hwif->OUTB(taskfile->feature, IDE_FEATURE_REG);
816 /* refers to number of sectors to transfer */
817 if (task->tf_out_flags.b.nsector)
818 hwif->OUTB(taskfile->sector_count, IDE_NSECTOR_REG);
819 /* refers to sector offset or start sector */
820 if (task->tf_out_flags.b.sector)
821 hwif->OUTB(taskfile->sector_number, IDE_SECTOR_REG);
822 if (task->tf_out_flags.b.lcyl)
823 hwif->OUTB(taskfile->low_cylinder, IDE_LCYL_REG);
824 if (task->tf_out_flags.b.hcyl)
825 hwif->OUTB(taskfile->high_cylinder, IDE_HCYL_REG);
828 * (ks) In the flagged taskfile approch, we will use all specified
829 * registers and the register value will not be changed, except the
830 * select bit (master/slave) in the drive_head register. We must make
831 * sure that the desired drive is selected.
833 hwif->OUTB(taskfile->device_head | drive->select.all, IDE_SELECT_REG);
834 switch(task->data_phase) {
836 case TASKFILE_OUT_DMAQ:
837 case TASKFILE_OUT_DMA:
838 case TASKFILE_IN_DMAQ:
839 case TASKFILE_IN_DMA:
840 hwif->dma_setup(drive);
841 hwif->dma_exec_cmd(drive, taskfile->command);
842 hwif->dma_start(drive);
846 if (task->handler == NULL)
849 /* Issue the command */
850 if (task->prehandler) {
851 hwif->OUTBSYNC(drive, taskfile->command, IDE_COMMAND_REG);
852 ndelay(400); /* FIXME */
853 return task->prehandler(drive, task->rq);
855 ide_execute_command(drive, taskfile->command, task->handler, WAIT_WORSTCASE, NULL);