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ide: Platform IDE driver
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e3a59b4d
HR
1/*
2 * ide-acpi.c
3 * Provides ACPI support for IDE drives.
4 *
5 * Copyright (C) 2005 Intel Corp.
6 * Copyright (C) 2005 Randy Dunlap
7 * Copyright (C) 2006 SUSE Linux Products GmbH
8 * Copyright (C) 2006 Hannes Reinecke
9 */
10
11#include <linux/ata.h>
12#include <linux/delay.h>
13#include <linux/device.h>
14#include <linux/errno.h>
15#include <linux/kernel.h>
16#include <acpi/acpi.h>
17#include <linux/ide.h>
18#include <linux/pci.h>
19
20#include <acpi/acpi_bus.h>
21#include <acpi/acnames.h>
22#include <acpi/acnamesp.h>
23#include <acpi/acparser.h>
24#include <acpi/acexcep.h>
25#include <acpi/acmacros.h>
26#include <acpi/actypes.h>
27
28#define REGS_PER_GTF 7
29struct taskfile_array {
30 u8 tfa[REGS_PER_GTF]; /* regs. 0x1f1 - 0x1f7 */
31};
32
33struct GTM_buffer {
34 u32 PIO_speed0;
35 u32 DMA_speed0;
36 u32 PIO_speed1;
37 u32 DMA_speed1;
38 u32 GTM_flags;
39};
40
41struct ide_acpi_drive_link {
42 ide_drive_t *drive;
43 acpi_handle obj_handle;
44 u8 idbuff[512];
45};
46
47struct ide_acpi_hwif_link {
48 ide_hwif_t *hwif;
49 acpi_handle obj_handle;
50 struct GTM_buffer gtm;
51 struct ide_acpi_drive_link master;
52 struct ide_acpi_drive_link slave;
53};
54
55#undef DEBUGGING
56/* note: adds function name and KERN_DEBUG */
57#ifdef DEBUGGING
58#define DEBPRINT(fmt, args...) \
59 printk(KERN_DEBUG "%s: " fmt, __FUNCTION__, ## args)
60#else
61#define DEBPRINT(fmt, args...) do {} while (0)
62#endif /* DEBUGGING */
63
64extern int ide_noacpi;
65extern int ide_noacpitfs;
66extern int ide_noacpionboot;
67
68/**
69 * ide_get_dev_handle - finds acpi_handle and PCI device.function
70 * @dev: device to locate
71 * @handle: returned acpi_handle for @dev
72 * @pcidevfn: return PCI device.func for @dev
73 *
74 * Returns the ACPI object handle to the corresponding PCI device.
75 *
76 * Returns 0 on success, <0 on error.
77 */
78static int ide_get_dev_handle(struct device *dev, acpi_handle *handle,
79 acpi_integer *pcidevfn)
80{
81 struct pci_dev *pdev = to_pci_dev(dev);
82 unsigned int bus, devnum, func;
83 acpi_integer addr;
84 acpi_handle dev_handle;
85 struct acpi_buffer buffer = {.length = ACPI_ALLOCATE_BUFFER,
86 .pointer = NULL};
87 acpi_status status;
88 struct acpi_device_info *dinfo = NULL;
89 int ret = -ENODEV;
90
91 bus = pdev->bus->number;
92 devnum = PCI_SLOT(pdev->devfn);
93 func = PCI_FUNC(pdev->devfn);
94 /* ACPI _ADR encoding for PCI bus: */
95 addr = (acpi_integer)(devnum << 16 | func);
96
97 DEBPRINT("ENTER: pci %02x:%02x.%01x\n", bus, devnum, func);
98
99 dev_handle = DEVICE_ACPI_HANDLE(dev);
100 if (!dev_handle) {
101 DEBPRINT("no acpi handle for device\n");
102 goto err;
103 }
104
105 status = acpi_get_object_info(dev_handle, &buffer);
106 if (ACPI_FAILURE(status)) {
107 DEBPRINT("get_object_info for device failed\n");
108 goto err;
109 }
110 dinfo = buffer.pointer;
111 if (dinfo && (dinfo->valid & ACPI_VALID_ADR) &&
112 dinfo->address == addr) {
113 *pcidevfn = addr;
114 *handle = dev_handle;
115 } else {
116 DEBPRINT("get_object_info for device has wrong "
117 " address: %llu, should be %u\n",
118 dinfo ? (unsigned long long)dinfo->address : -1ULL,
119 (unsigned int)addr);
120 goto err;
121 }
122
123 DEBPRINT("for dev=0x%x.%x, addr=0x%llx, *handle=0x%p\n",
124 devnum, func, (unsigned long long)addr, *handle);
125 ret = 0;
126err:
127 kfree(dinfo);
128 return ret;
129}
130
131/**
132 * ide_acpi_hwif_get_handle - Get ACPI object handle for a given hwif
133 * @hwif: device to locate
134 *
135 * Retrieves the object handle for a given hwif.
136 *
137 * Returns handle on success, 0 on error.
138 */
139static acpi_handle ide_acpi_hwif_get_handle(ide_hwif_t *hwif)
140{
141 struct device *dev = hwif->gendev.parent;
142 acpi_handle dev_handle;
143 acpi_integer pcidevfn;
144 acpi_handle chan_handle;
145 int err;
146
147 DEBPRINT("ENTER: device %s\n", hwif->name);
148
149 if (!dev) {
150 DEBPRINT("no PCI device for %s\n", hwif->name);
151 return NULL;
152 }
153
154 err = ide_get_dev_handle(dev, &dev_handle, &pcidevfn);
155 if (err < 0) {
156 DEBPRINT("ide_get_dev_handle failed (%d)\n", err);
157 return NULL;
158 }
159
160 /* get child objects of dev_handle == channel objects,
161 * + _their_ children == drive objects */
162 /* channel is hwif->channel */
163 chan_handle = acpi_get_child(dev_handle, hwif->channel);
164 DEBPRINT("chan adr=%d: handle=0x%p\n",
165 hwif->channel, chan_handle);
166
167 return chan_handle;
168}
169
170/**
171 * ide_acpi_drive_get_handle - Get ACPI object handle for a given drive
172 * @drive: device to locate
173 *
174 * Retrieves the object handle of a given drive. According to the ACPI
175 * spec the drive is a child of the hwif.
176 *
177 * Returns handle on success, 0 on error.
178 */
179static acpi_handle ide_acpi_drive_get_handle(ide_drive_t *drive)
180{
181 ide_hwif_t *hwif = HWIF(drive);
182 int port;
183 acpi_handle drive_handle;
184
185 if (!hwif->acpidata)
186 return NULL;
187
188 if (!hwif->acpidata->obj_handle)
189 return NULL;
190
191 port = hwif->channel ? drive->dn - 2: drive->dn;
192
193 DEBPRINT("ENTER: %s at channel#: %d port#: %d\n",
194 drive->name, hwif->channel, port);
195
196
197 /* TBD: could also check ACPI object VALID bits */
198 drive_handle = acpi_get_child(hwif->acpidata->obj_handle, port);
199 DEBPRINT("drive %s handle 0x%p\n", drive->name, drive_handle);
200
201 return drive_handle;
202}
203
204/**
205 * do_drive_get_GTF - get the drive bootup default taskfile settings
206 * @drive: the drive for which the taskfile settings should be retrieved
207 * @gtf_length: number of bytes of _GTF data returned at @gtf_address
208 * @gtf_address: buffer containing _GTF taskfile arrays
209 *
210 * The _GTF method has no input parameters.
211 * It returns a variable number of register set values (registers
212 * hex 1F1..1F7, taskfiles).
213 * The <variable number> is not known in advance, so have ACPI-CA
214 * allocate the buffer as needed and return it, then free it later.
215 *
216 * The returned @gtf_length and @gtf_address are only valid if the
217 * function return value is 0.
218 */
219static int do_drive_get_GTF(ide_drive_t *drive,
220 unsigned int *gtf_length, unsigned long *gtf_address,
221 unsigned long *obj_loc)
222{
223 acpi_status status;
224 struct acpi_buffer output;
225 union acpi_object *out_obj;
226 ide_hwif_t *hwif = HWIF(drive);
227 struct device *dev = hwif->gendev.parent;
228 int err = -ENODEV;
229 int port;
230
231 *gtf_length = 0;
232 *gtf_address = 0UL;
233 *obj_loc = 0UL;
234
235 if (ide_noacpi)
236 return 0;
237
238 if (!dev) {
239 DEBPRINT("no PCI device for %s\n", hwif->name);
240 goto out;
241 }
242
243 if (!hwif->acpidata) {
244 DEBPRINT("no ACPI data for %s\n", hwif->name);
245 goto out;
246 }
247
248 port = hwif->channel ? drive->dn - 2: drive->dn;
249
250 if (!drive->acpidata) {
251 if (port == 0) {
252 drive->acpidata = &hwif->acpidata->master;
253 hwif->acpidata->master.drive = drive;
254 } else {
255 drive->acpidata = &hwif->acpidata->slave;
256 hwif->acpidata->slave.drive = drive;
257 }
258 }
259
260 DEBPRINT("ENTER: %s at %s, port#: %d, hard_port#: %d\n",
261 hwif->name, dev->bus_id, port, hwif->channel);
262
263 if (!drive->present) {
264 DEBPRINT("%s drive %d:%d not present\n",
265 hwif->name, hwif->channel, port);
266 goto out;
267 }
268
269 /* Get this drive's _ADR info. if not already known. */
270 if (!drive->acpidata->obj_handle) {
271 drive->acpidata->obj_handle = ide_acpi_drive_get_handle(drive);
272 if (!drive->acpidata->obj_handle) {
273 DEBPRINT("No ACPI object found for %s\n",
274 drive->name);
275 goto out;
276 }
277 }
278
279 /* Setting up output buffer */
280 output.length = ACPI_ALLOCATE_BUFFER;
281 output.pointer = NULL; /* ACPI-CA sets this; save/free it later */
282
283 /* _GTF has no input parameters */
284 err = -EIO;
285 status = acpi_evaluate_object(drive->acpidata->obj_handle, "_GTF",
286 NULL, &output);
287 if (ACPI_FAILURE(status)) {
288 printk(KERN_DEBUG
289 "%s: Run _GTF error: status = 0x%x\n",
290 __FUNCTION__, status);
291 goto out;
292 }
293
294 if (!output.length || !output.pointer) {
295 DEBPRINT("Run _GTF: "
296 "length or ptr is NULL (0x%llx, 0x%p)\n",
297 (unsigned long long)output.length,
298 output.pointer);
299 goto out;
300 }
301
302 out_obj = output.pointer;
303 if (out_obj->type != ACPI_TYPE_BUFFER) {
304 DEBPRINT("Run _GTF: error: "
305 "expected object type of ACPI_TYPE_BUFFER, "
306 "got 0x%x\n", out_obj->type);
307 err = -ENOENT;
308 kfree(output.pointer);
309 goto out;
310 }
311
312 if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
313 out_obj->buffer.length % REGS_PER_GTF) {
314 printk(KERN_ERR
315 "%s: unexpected GTF length (%d) or addr (0x%p)\n",
316 __FUNCTION__, out_obj->buffer.length,
317 out_obj->buffer.pointer);
318 err = -ENOENT;
319 kfree(output.pointer);
320 goto out;
321 }
322
323 *gtf_length = out_obj->buffer.length;
324 *gtf_address = (unsigned long)out_obj->buffer.pointer;
325 *obj_loc = (unsigned long)out_obj;
326 DEBPRINT("returning gtf_length=%d, gtf_address=0x%lx, obj_loc=0x%lx\n",
327 *gtf_length, *gtf_address, *obj_loc);
328 err = 0;
329out:
330 return err;
331}
332
333/**
334 * taskfile_load_raw - send taskfile registers to drive
335 * @drive: drive to which output is sent
336 * @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)
337 *
338 * Outputs IDE taskfile to the drive.
339 */
340static int taskfile_load_raw(ide_drive_t *drive,
341 const struct taskfile_array *gtf)
342{
343 ide_task_t args;
344 int err = 0;
345
346 DEBPRINT("(0x1f1-1f7): hex: "
347 "%02x %02x %02x %02x %02x %02x %02x\n",
348 gtf->tfa[0], gtf->tfa[1], gtf->tfa[2],
349 gtf->tfa[3], gtf->tfa[4], gtf->tfa[5], gtf->tfa[6]);
350
351 memset(&args, 0, sizeof(ide_task_t));
352 args.command_type = IDE_DRIVE_TASK_NO_DATA;
353 args.data_phase = TASKFILE_IN;
354 args.handler = &task_no_data_intr;
355
356 /* convert gtf to IDE Taskfile */
357 args.tfRegister[1] = gtf->tfa[0]; /* 0x1f1 */
358 args.tfRegister[2] = gtf->tfa[1]; /* 0x1f2 */
359 args.tfRegister[3] = gtf->tfa[2]; /* 0x1f3 */
360 args.tfRegister[4] = gtf->tfa[3]; /* 0x1f4 */
361 args.tfRegister[5] = gtf->tfa[4]; /* 0x1f5 */
362 args.tfRegister[6] = gtf->tfa[5]; /* 0x1f6 */
363 args.tfRegister[7] = gtf->tfa[6]; /* 0x1f7 */
364
365 if (ide_noacpitfs) {
366 DEBPRINT("_GTF execution disabled\n");
367 return err;
368 }
369
370 err = ide_raw_taskfile(drive, &args, NULL);
371 if (err)
372 printk(KERN_ERR "%s: ide_raw_taskfile failed: %u\n",
373 __FUNCTION__, err);
374
375 return err;
376}
377
378/**
379 * do_drive_set_taskfiles - write the drive taskfile settings from _GTF
380 * @drive: the drive to which the taskfile command should be sent
381 * @gtf_length: total number of bytes of _GTF taskfiles
382 * @gtf_address: location of _GTF taskfile arrays
383 *
384 * Write {gtf_address, length gtf_length} in groups of
385 * REGS_PER_GTF bytes.
386 */
387static int do_drive_set_taskfiles(ide_drive_t *drive,
388 unsigned int gtf_length,
389 unsigned long gtf_address)
390{
391 int rc = -ENODEV, err;
392 int gtf_count = gtf_length / REGS_PER_GTF;
393 int ix;
394 struct taskfile_array *gtf;
395
396 if (ide_noacpi)
397 return 0;
398
399 DEBPRINT("ENTER: %s, hard_port#: %d\n", drive->name, drive->dn);
400
401 if (!drive->present)
402 goto out;
403 if (!gtf_count) /* shouldn't be here */
404 goto out;
405
406 DEBPRINT("total GTF bytes=%u (0x%x), gtf_count=%d, addr=0x%lx\n",
407 gtf_length, gtf_length, gtf_count, gtf_address);
408
409 if (gtf_length % REGS_PER_GTF) {
410 printk(KERN_ERR "%s: unexpected GTF length (%d)\n",
411 __FUNCTION__, gtf_length);
412 goto out;
413 }
414
415 rc = 0;
416 for (ix = 0; ix < gtf_count; ix++) {
417 gtf = (struct taskfile_array *)
418 (gtf_address + ix * REGS_PER_GTF);
419
420 /* send all TaskFile registers (0x1f1-0x1f7) *in*that*order* */
421 err = taskfile_load_raw(drive, gtf);
422 if (err)
423 rc = err;
424 }
425
426out:
427 return rc;
428}
429
430/**
431 * ide_acpi_exec_tfs - get then write drive taskfile settings
432 * @drive: the drive for which the taskfile settings should be
433 * written.
434 *
435 * According to the ACPI spec this should be called after _STM
436 * has been evaluated for the interface. Some ACPI vendors interpret
437 * that as a hard requirement and modify the taskfile according
438 * to the Identify Drive information passed down with _STM.
439 * So one should really make sure to call this only after _STM has
440 * been executed.
441 */
442int ide_acpi_exec_tfs(ide_drive_t *drive)
443{
444 int ret;
445 unsigned int gtf_length;
446 unsigned long gtf_address;
447 unsigned long obj_loc;
448
449 if (ide_noacpi)
450 return 0;
451
452 DEBPRINT("call get_GTF, drive=%s port=%d\n", drive->name, drive->dn);
453
454 ret = do_drive_get_GTF(drive, &gtf_length, &gtf_address, &obj_loc);
455 if (ret < 0) {
456 DEBPRINT("get_GTF error (%d)\n", ret);
457 return ret;
458 }
459
460 DEBPRINT("call set_taskfiles, drive=%s\n", drive->name);
461
462 ret = do_drive_set_taskfiles(drive, gtf_length, gtf_address);
463 kfree((void *)obj_loc);
464 if (ret < 0) {
465 DEBPRINT("set_taskfiles error (%d)\n", ret);
466 }
467
468 DEBPRINT("ret=%d\n", ret);
469
470 return ret;
471}
472EXPORT_SYMBOL_GPL(ide_acpi_exec_tfs);
473
474/**
475 * ide_acpi_get_timing - get the channel (controller) timings
476 * @hwif: target IDE interface (channel)
477 *
478 * This function executes the _GTM ACPI method for the target channel.
479 *
480 */
481void ide_acpi_get_timing(ide_hwif_t *hwif)
482{
483 acpi_status status;
484 struct acpi_buffer output;
485 union acpi_object *out_obj;
486
487 if (ide_noacpi)
488 return;
489
490 DEBPRINT("ENTER:\n");
491
492 if (!hwif->acpidata) {
493 DEBPRINT("no ACPI data for %s\n", hwif->name);
494 return;
495 }
496
497 /* Setting up output buffer for _GTM */
498 output.length = ACPI_ALLOCATE_BUFFER;
499 output.pointer = NULL; /* ACPI-CA sets this; save/free it later */
500
501 /* _GTM has no input parameters */
502 status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_GTM",
503 NULL, &output);
504
505 DEBPRINT("_GTM status: %d, outptr: 0x%p, outlen: 0x%llx\n",
506 status, output.pointer,
507 (unsigned long long)output.length);
508
509 if (ACPI_FAILURE(status)) {
510 DEBPRINT("Run _GTM error: status = 0x%x\n", status);
511 return;
512 }
513
514 if (!output.length || !output.pointer) {
515 DEBPRINT("Run _GTM: length or ptr is NULL (0x%llx, 0x%p)\n",
516 (unsigned long long)output.length,
517 output.pointer);
518 kfree(output.pointer);
519 return;
520 }
521
522 out_obj = output.pointer;
523 if (out_obj->type != ACPI_TYPE_BUFFER) {
524 kfree(output.pointer);
525 DEBPRINT("Run _GTM: error: "
526 "expected object type of ACPI_TYPE_BUFFER, "
527 "got 0x%x\n", out_obj->type);
528 return;
529 }
530
531 if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
532 out_obj->buffer.length != sizeof(struct GTM_buffer)) {
533 kfree(output.pointer);
534 printk(KERN_ERR
1e8f34f7
AM
535 "%s: unexpected _GTM length (0x%x)[should be 0x%zx] or "
536 "addr (0x%p)\n",
537 __FUNCTION__, out_obj->buffer.length,
538 sizeof(struct GTM_buffer), out_obj->buffer.pointer);
e3a59b4d
HR
539 return;
540 }
541
542 memcpy(&hwif->acpidata->gtm, out_obj->buffer.pointer,
543 sizeof(struct GTM_buffer));
544
545 DEBPRINT("_GTM info: ptr: 0x%p, len: 0x%x, exp.len: 0x%Zx\n",
546 out_obj->buffer.pointer, out_obj->buffer.length,
547 sizeof(struct GTM_buffer));
548
549 DEBPRINT("_GTM fields: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
550 hwif->acpidata->gtm.PIO_speed0,
551 hwif->acpidata->gtm.DMA_speed0,
552 hwif->acpidata->gtm.PIO_speed1,
553 hwif->acpidata->gtm.DMA_speed1,
554 hwif->acpidata->gtm.GTM_flags);
555
556 kfree(output.pointer);
557}
558EXPORT_SYMBOL_GPL(ide_acpi_get_timing);
559
560/**
561 * ide_acpi_push_timing - set the channel (controller) timings
562 * @hwif: target IDE interface (channel)
563 *
564 * This function executes the _STM ACPI method for the target channel.
565 *
566 * _STM requires Identify Drive data, which has to passed as an argument.
567 * Unfortunately hd_driveid is a mangled version which we can't readily
568 * use; hence we'll get the information afresh.
569 */
570void ide_acpi_push_timing(ide_hwif_t *hwif)
571{
572 acpi_status status;
573 struct acpi_object_list input;
574 union acpi_object in_params[3];
575 struct ide_acpi_drive_link *master = &hwif->acpidata->master;
576 struct ide_acpi_drive_link *slave = &hwif->acpidata->slave;
577
578 if (ide_noacpi)
579 return;
580
581 DEBPRINT("ENTER:\n");
582
583 if (!hwif->acpidata) {
584 DEBPRINT("no ACPI data for %s\n", hwif->name);
585 return;
586 }
587
588 /* Give the GTM buffer + drive Identify data to the channel via the
589 * _STM method: */
590 /* setup input parameters buffer for _STM */
591 input.count = 3;
592 input.pointer = in_params;
593 in_params[0].type = ACPI_TYPE_BUFFER;
594 in_params[0].buffer.length = sizeof(struct GTM_buffer);
595 in_params[0].buffer.pointer = (u8 *)&hwif->acpidata->gtm;
596 in_params[1].type = ACPI_TYPE_BUFFER;
597 in_params[1].buffer.length = sizeof(struct hd_driveid);
598 in_params[1].buffer.pointer = (u8 *)&master->idbuff;
599 in_params[2].type = ACPI_TYPE_BUFFER;
600 in_params[2].buffer.length = sizeof(struct hd_driveid);
601 in_params[2].buffer.pointer = (u8 *)&slave->idbuff;
602 /* Output buffer: _STM has no output */
603
604 status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_STM",
605 &input, NULL);
606
607 if (ACPI_FAILURE(status)) {
608 DEBPRINT("Run _STM error: status = 0x%x\n", status);
609 }
610 DEBPRINT("_STM status: %d\n", status);
611}
612EXPORT_SYMBOL_GPL(ide_acpi_push_timing);
613
614/**
615 * ide_acpi_init - initialize the ACPI link for an IDE interface
616 * @hwif: target IDE interface (channel)
617 *
618 * The ACPI spec is not quite clear when the drive identify buffer
619 * should be obtained. Calling IDENTIFY DEVICE during shutdown
620 * is not the best of ideas as the drive might already being put to
621 * sleep. And obviously we can't call it during resume.
622 * So we get the information during startup; but this means that
623 * any changes during run-time will be lost after resume.
624 */
625void ide_acpi_init(ide_hwif_t *hwif)
626{
627 int unit;
628 int err;
629 struct ide_acpi_drive_link *master;
630 struct ide_acpi_drive_link *slave;
631
632 hwif->acpidata = kzalloc(sizeof(struct ide_acpi_hwif_link), GFP_KERNEL);
633 if (!hwif->acpidata)
634 return;
635
636 hwif->acpidata->obj_handle = ide_acpi_hwif_get_handle(hwif);
637 if (!hwif->acpidata->obj_handle) {
638 DEBPRINT("no ACPI object for %s found\n", hwif->name);
639 kfree(hwif->acpidata);
640 hwif->acpidata = NULL;
641 return;
642 }
643
644 /*
645 * The ACPI spec mandates that we send information
646 * for both drives, regardless whether they are connected
647 * or not.
648 */
649 hwif->acpidata->master.drive = &hwif->drives[0];
650 hwif->drives[0].acpidata = &hwif->acpidata->master;
651 master = &hwif->acpidata->master;
652
653 hwif->acpidata->slave.drive = &hwif->drives[1];
654 hwif->drives[1].acpidata = &hwif->acpidata->slave;
655 slave = &hwif->acpidata->slave;
656
657
658 /*
659 * Send IDENTIFY for each drive
660 */
661 if (master->drive->present) {
662 err = taskfile_lib_get_identify(master->drive, master->idbuff);
663 if (err) {
664 DEBPRINT("identify device %s failed (%d)\n",
665 master->drive->name, err);
666 }
667 }
668
669 if (slave->drive->present) {
670 err = taskfile_lib_get_identify(slave->drive, slave->idbuff);
671 if (err) {
672 DEBPRINT("identify device %s failed (%d)\n",
673 slave->drive->name, err);
674 }
675 }
676
677 if (ide_noacpionboot) {
678 DEBPRINT("ACPI methods disabled on boot\n");
679 return;
680 }
681
682 /*
683 * ACPI requires us to call _STM on startup
684 */
685 ide_acpi_get_timing(hwif);
686 ide_acpi_push_timing(hwif);
687
688 for (unit = 0; unit < MAX_DRIVES; ++unit) {
689 ide_drive_t *drive = &hwif->drives[unit];
690
691 if (drive->present) {
692 /* Execute ACPI startup code */
693 ide_acpi_exec_tfs(drive);
694 }
695 }
696}
697EXPORT_SYMBOL_GPL(ide_acpi_init);