xref: /openbmc/linux/drivers/ata/libata-acpi.c (revision 63dc02bd)
1 /*
2  * libata-acpi.c
3  * Provides ACPI support for PATA/SATA.
4  *
5  * Copyright (C) 2006 Intel Corp.
6  * Copyright (C) 2006 Randy Dunlap
7  */
8 
9 #include <linux/module.h>
10 #include <linux/ata.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/errno.h>
14 #include <linux/kernel.h>
15 #include <linux/acpi.h>
16 #include <linux/libata.h>
17 #include <linux/pci.h>
18 #include <linux/slab.h>
19 #include <scsi/scsi_device.h>
20 #include "libata.h"
21 
22 #include <acpi/acpi_bus.h>
23 
24 unsigned int ata_acpi_gtf_filter = ATA_ACPI_FILTER_DEFAULT;
25 module_param_named(acpi_gtf_filter, ata_acpi_gtf_filter, int, 0644);
26 MODULE_PARM_DESC(acpi_gtf_filter, "filter mask for ACPI _GTF commands, set to filter out (0x1=set xfermode, 0x2=lock/freeze lock, 0x4=DIPM, 0x8=FPDMA non-zero offset, 0x10=FPDMA DMA Setup FIS auto-activate)");
27 
28 #define NO_PORT_MULT		0xffff
29 #define SATA_ADR(root, pmp)	(((root) << 16) | (pmp))
30 
31 #define REGS_PER_GTF		7
32 struct ata_acpi_gtf {
33 	u8	tf[REGS_PER_GTF];	/* regs. 0x1f1 - 0x1f7 */
34 } __packed;
35 
36 /*
37  *	Helper - belongs in the PCI layer somewhere eventually
38  */
39 static int is_pci_dev(struct device *dev)
40 {
41 	return (dev->bus == &pci_bus_type);
42 }
43 
44 static void ata_acpi_clear_gtf(struct ata_device *dev)
45 {
46 	kfree(dev->gtf_cache);
47 	dev->gtf_cache = NULL;
48 }
49 
50 /**
51  * ata_acpi_associate_sata_port - associate SATA port with ACPI objects
52  * @ap: target SATA port
53  *
54  * Look up ACPI objects associated with @ap and initialize acpi_handle
55  * fields of @ap, the port and devices accordingly.
56  *
57  * LOCKING:
58  * EH context.
59  *
60  * RETURNS:
61  * 0 on success, -errno on failure.
62  */
63 void ata_acpi_associate_sata_port(struct ata_port *ap)
64 {
65 	WARN_ON(!(ap->flags & ATA_FLAG_ACPI_SATA));
66 
67 	if (!sata_pmp_attached(ap)) {
68 		u64 adr = SATA_ADR(ap->port_no, NO_PORT_MULT);
69 
70 		ap->link.device->acpi_handle =
71 			acpi_get_child(ap->host->acpi_handle, adr);
72 	} else {
73 		struct ata_link *link;
74 
75 		ap->link.device->acpi_handle = NULL;
76 
77 		ata_for_each_link(link, ap, EDGE) {
78 			u64 adr = SATA_ADR(ap->port_no, link->pmp);
79 
80 			link->device->acpi_handle =
81 				acpi_get_child(ap->host->acpi_handle, adr);
82 		}
83 	}
84 }
85 
86 static void ata_acpi_associate_ide_port(struct ata_port *ap)
87 {
88 	int max_devices, i;
89 
90 	ap->acpi_handle = acpi_get_child(ap->host->acpi_handle, ap->port_no);
91 	if (!ap->acpi_handle)
92 		return;
93 
94 	max_devices = 1;
95 	if (ap->flags & ATA_FLAG_SLAVE_POSS)
96 		max_devices++;
97 
98 	for (i = 0; i < max_devices; i++) {
99 		struct ata_device *dev = &ap->link.device[i];
100 
101 		dev->acpi_handle = acpi_get_child(ap->acpi_handle, i);
102 	}
103 
104 	if (ata_acpi_gtm(ap, &ap->__acpi_init_gtm) == 0)
105 		ap->pflags |= ATA_PFLAG_INIT_GTM_VALID;
106 }
107 
108 /* @ap and @dev are the same as ata_acpi_handle_hotplug() */
109 static void ata_acpi_detach_device(struct ata_port *ap, struct ata_device *dev)
110 {
111 	if (dev)
112 		dev->flags |= ATA_DFLAG_DETACH;
113 	else {
114 		struct ata_link *tlink;
115 		struct ata_device *tdev;
116 
117 		ata_for_each_link(tlink, ap, EDGE)
118 			ata_for_each_dev(tdev, tlink, ALL)
119 				tdev->flags |= ATA_DFLAG_DETACH;
120 	}
121 
122 	ata_port_schedule_eh(ap);
123 }
124 
125 /**
126  * ata_acpi_handle_hotplug - ACPI event handler backend
127  * @ap: ATA port ACPI event occurred
128  * @dev: ATA device ACPI event occurred (can be NULL)
129  * @event: ACPI event which occurred
130  *
131  * All ACPI bay / device realted events end up in this function.  If
132  * the event is port-wide @dev is NULL.  If the event is specific to a
133  * device, @dev points to it.
134  *
135  * Hotplug (as opposed to unplug) notification is always handled as
136  * port-wide while unplug only kills the target device on device-wide
137  * event.
138  *
139  * LOCKING:
140  * ACPI notify handler context.  May sleep.
141  */
142 static void ata_acpi_handle_hotplug(struct ata_port *ap, struct ata_device *dev,
143 				    u32 event)
144 {
145 	struct ata_eh_info *ehi = &ap->link.eh_info;
146 	int wait = 0;
147 	unsigned long flags;
148 
149 	spin_lock_irqsave(ap->lock, flags);
150 	/*
151 	 * When dock driver calls into the routine, it will always use
152 	 * ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
153 	 * ACPI_NOTIFY_EJECT_REQUEST for remove
154 	 */
155 	switch (event) {
156 	case ACPI_NOTIFY_BUS_CHECK:
157 	case ACPI_NOTIFY_DEVICE_CHECK:
158 		ata_ehi_push_desc(ehi, "ACPI event");
159 
160 		ata_ehi_hotplugged(ehi);
161 		ata_port_freeze(ap);
162 		break;
163 	case ACPI_NOTIFY_EJECT_REQUEST:
164 		ata_ehi_push_desc(ehi, "ACPI event");
165 
166 		ata_acpi_detach_device(ap, dev);
167 		wait = 1;
168 		break;
169 	}
170 
171 	spin_unlock_irqrestore(ap->lock, flags);
172 
173 	if (wait)
174 		ata_port_wait_eh(ap);
175 }
176 
177 static void ata_acpi_dev_notify_dock(acpi_handle handle, u32 event, void *data)
178 {
179 	struct ata_device *dev = data;
180 
181 	ata_acpi_handle_hotplug(dev->link->ap, dev, event);
182 }
183 
184 static void ata_acpi_ap_notify_dock(acpi_handle handle, u32 event, void *data)
185 {
186 	struct ata_port *ap = data;
187 
188 	ata_acpi_handle_hotplug(ap, NULL, event);
189 }
190 
191 static void ata_acpi_uevent(struct ata_port *ap, struct ata_device *dev,
192 	u32 event)
193 {
194 	struct kobject *kobj = NULL;
195 	char event_string[20];
196 	char *envp[] = { event_string, NULL };
197 
198 	if (dev) {
199 		if (dev->sdev)
200 			kobj = &dev->sdev->sdev_gendev.kobj;
201 	} else
202 		kobj = &ap->dev->kobj;
203 
204 	if (kobj) {
205 		snprintf(event_string, 20, "BAY_EVENT=%d", event);
206 		kobject_uevent_env(kobj, KOBJ_CHANGE, envp);
207 	}
208 }
209 
210 static void ata_acpi_ap_uevent(acpi_handle handle, u32 event, void *data)
211 {
212 	ata_acpi_uevent(data, NULL, event);
213 }
214 
215 static void ata_acpi_dev_uevent(acpi_handle handle, u32 event, void *data)
216 {
217 	struct ata_device *dev = data;
218 	ata_acpi_uevent(dev->link->ap, dev, event);
219 }
220 
221 static const struct acpi_dock_ops ata_acpi_dev_dock_ops = {
222 	.handler = ata_acpi_dev_notify_dock,
223 	.uevent = ata_acpi_dev_uevent,
224 };
225 
226 static const struct acpi_dock_ops ata_acpi_ap_dock_ops = {
227 	.handler = ata_acpi_ap_notify_dock,
228 	.uevent = ata_acpi_ap_uevent,
229 };
230 
231 /**
232  * ata_acpi_associate - associate ATA host with ACPI objects
233  * @host: target ATA host
234  *
235  * Look up ACPI objects associated with @host and initialize
236  * acpi_handle fields of @host, its ports and devices accordingly.
237  *
238  * LOCKING:
239  * EH context.
240  *
241  * RETURNS:
242  * 0 on success, -errno on failure.
243  */
244 void ata_acpi_associate(struct ata_host *host)
245 {
246 	int i, j;
247 
248 	if (!is_pci_dev(host->dev) || libata_noacpi)
249 		return;
250 
251 	host->acpi_handle = DEVICE_ACPI_HANDLE(host->dev);
252 	if (!host->acpi_handle)
253 		return;
254 
255 	for (i = 0; i < host->n_ports; i++) {
256 		struct ata_port *ap = host->ports[i];
257 
258 		if (host->ports[0]->flags & ATA_FLAG_ACPI_SATA)
259 			ata_acpi_associate_sata_port(ap);
260 		else
261 			ata_acpi_associate_ide_port(ap);
262 
263 		if (ap->acpi_handle) {
264 			/* we might be on a docking station */
265 			register_hotplug_dock_device(ap->acpi_handle,
266 					     &ata_acpi_ap_dock_ops, ap);
267 		}
268 
269 		for (j = 0; j < ata_link_max_devices(&ap->link); j++) {
270 			struct ata_device *dev = &ap->link.device[j];
271 
272 			if (dev->acpi_handle) {
273 				/* we might be on a docking station */
274 				register_hotplug_dock_device(dev->acpi_handle,
275 					     &ata_acpi_dev_dock_ops, dev);
276 			}
277 		}
278 	}
279 }
280 
281 /**
282  * ata_acpi_dissociate - dissociate ATA host from ACPI objects
283  * @host: target ATA host
284  *
285  * This function is called during driver detach after the whole host
286  * is shut down.
287  *
288  * LOCKING:
289  * EH context.
290  */
291 void ata_acpi_dissociate(struct ata_host *host)
292 {
293 	int i;
294 
295 	/* Restore initial _GTM values so that driver which attaches
296 	 * afterward can use them too.
297 	 */
298 	for (i = 0; i < host->n_ports; i++) {
299 		struct ata_port *ap = host->ports[i];
300 		const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
301 
302 		if (ap->acpi_handle && gtm)
303 			ata_acpi_stm(ap, gtm);
304 	}
305 }
306 
307 /**
308  * ata_acpi_gtm - execute _GTM
309  * @ap: target ATA port
310  * @gtm: out parameter for _GTM result
311  *
312  * Evaluate _GTM and store the result in @gtm.
313  *
314  * LOCKING:
315  * EH context.
316  *
317  * RETURNS:
318  * 0 on success, -ENOENT if _GTM doesn't exist, -errno on failure.
319  */
320 int ata_acpi_gtm(struct ata_port *ap, struct ata_acpi_gtm *gtm)
321 {
322 	struct acpi_buffer output = { .length = ACPI_ALLOCATE_BUFFER };
323 	union acpi_object *out_obj;
324 	acpi_status status;
325 	int rc = 0;
326 
327 	status = acpi_evaluate_object(ap->acpi_handle, "_GTM", NULL, &output);
328 
329 	rc = -ENOENT;
330 	if (status == AE_NOT_FOUND)
331 		goto out_free;
332 
333 	rc = -EINVAL;
334 	if (ACPI_FAILURE(status)) {
335 		ata_port_err(ap, "ACPI get timing mode failed (AE 0x%x)\n",
336 			     status);
337 		goto out_free;
338 	}
339 
340 	out_obj = output.pointer;
341 	if (out_obj->type != ACPI_TYPE_BUFFER) {
342 		ata_port_warn(ap, "_GTM returned unexpected object type 0x%x\n",
343 			      out_obj->type);
344 
345 		goto out_free;
346 	}
347 
348 	if (out_obj->buffer.length != sizeof(struct ata_acpi_gtm)) {
349 		ata_port_err(ap, "_GTM returned invalid length %d\n",
350 			     out_obj->buffer.length);
351 		goto out_free;
352 	}
353 
354 	memcpy(gtm, out_obj->buffer.pointer, sizeof(struct ata_acpi_gtm));
355 	rc = 0;
356  out_free:
357 	kfree(output.pointer);
358 	return rc;
359 }
360 
361 EXPORT_SYMBOL_GPL(ata_acpi_gtm);
362 
363 /**
364  * ata_acpi_stm - execute _STM
365  * @ap: target ATA port
366  * @stm: timing parameter to _STM
367  *
368  * Evaluate _STM with timing parameter @stm.
369  *
370  * LOCKING:
371  * EH context.
372  *
373  * RETURNS:
374  * 0 on success, -ENOENT if _STM doesn't exist, -errno on failure.
375  */
376 int ata_acpi_stm(struct ata_port *ap, const struct ata_acpi_gtm *stm)
377 {
378 	acpi_status status;
379 	struct ata_acpi_gtm		stm_buf = *stm;
380 	struct acpi_object_list         input;
381 	union acpi_object               in_params[3];
382 
383 	in_params[0].type = ACPI_TYPE_BUFFER;
384 	in_params[0].buffer.length = sizeof(struct ata_acpi_gtm);
385 	in_params[0].buffer.pointer = (u8 *)&stm_buf;
386 	/* Buffers for id may need byteswapping ? */
387 	in_params[1].type = ACPI_TYPE_BUFFER;
388 	in_params[1].buffer.length = 512;
389 	in_params[1].buffer.pointer = (u8 *)ap->link.device[0].id;
390 	in_params[2].type = ACPI_TYPE_BUFFER;
391 	in_params[2].buffer.length = 512;
392 	in_params[2].buffer.pointer = (u8 *)ap->link.device[1].id;
393 
394 	input.count = 3;
395 	input.pointer = in_params;
396 
397 	status = acpi_evaluate_object(ap->acpi_handle, "_STM", &input, NULL);
398 
399 	if (status == AE_NOT_FOUND)
400 		return -ENOENT;
401 	if (ACPI_FAILURE(status)) {
402 		ata_port_err(ap, "ACPI set timing mode failed (status=0x%x)\n",
403 			     status);
404 		return -EINVAL;
405 	}
406 	return 0;
407 }
408 
409 EXPORT_SYMBOL_GPL(ata_acpi_stm);
410 
411 /**
412  * ata_dev_get_GTF - get the drive bootup default taskfile settings
413  * @dev: target ATA device
414  * @gtf: output parameter for buffer containing _GTF taskfile arrays
415  *
416  * This applies to both PATA and SATA drives.
417  *
418  * The _GTF method has no input parameters.
419  * It returns a variable number of register set values (registers
420  * hex 1F1..1F7, taskfiles).
421  * The <variable number> is not known in advance, so have ACPI-CA
422  * allocate the buffer as needed and return it, then free it later.
423  *
424  * LOCKING:
425  * EH context.
426  *
427  * RETURNS:
428  * Number of taskfiles on success, 0 if _GTF doesn't exist.  -EINVAL
429  * if _GTF is invalid.
430  */
431 static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf)
432 {
433 	struct ata_port *ap = dev->link->ap;
434 	acpi_status status;
435 	struct acpi_buffer output;
436 	union acpi_object *out_obj;
437 	int rc = 0;
438 
439 	/* if _GTF is cached, use the cached value */
440 	if (dev->gtf_cache) {
441 		out_obj = dev->gtf_cache;
442 		goto done;
443 	}
444 
445 	/* set up output buffer */
446 	output.length = ACPI_ALLOCATE_BUFFER;
447 	output.pointer = NULL;	/* ACPI-CA sets this; save/free it later */
448 
449 	if (ata_msg_probe(ap))
450 		ata_dev_dbg(dev, "%s: ENTER: port#: %d\n",
451 			    __func__, ap->port_no);
452 
453 	/* _GTF has no input parameters */
454 	status = acpi_evaluate_object(dev->acpi_handle, "_GTF", NULL, &output);
455 	out_obj = dev->gtf_cache = output.pointer;
456 
457 	if (ACPI_FAILURE(status)) {
458 		if (status != AE_NOT_FOUND) {
459 			ata_dev_warn(dev, "_GTF evaluation failed (AE 0x%x)\n",
460 				     status);
461 			rc = -EINVAL;
462 		}
463 		goto out_free;
464 	}
465 
466 	if (!output.length || !output.pointer) {
467 		if (ata_msg_probe(ap))
468 			ata_dev_dbg(dev, "%s: Run _GTF: length or ptr is NULL (0x%llx, 0x%p)\n",
469 				    __func__,
470 				    (unsigned long long)output.length,
471 				    output.pointer);
472 		rc = -EINVAL;
473 		goto out_free;
474 	}
475 
476 	if (out_obj->type != ACPI_TYPE_BUFFER) {
477 		ata_dev_warn(dev, "_GTF unexpected object type 0x%x\n",
478 			     out_obj->type);
479 		rc = -EINVAL;
480 		goto out_free;
481 	}
482 
483 	if (out_obj->buffer.length % REGS_PER_GTF) {
484 		ata_dev_warn(dev, "unexpected _GTF length (%d)\n",
485 			     out_obj->buffer.length);
486 		rc = -EINVAL;
487 		goto out_free;
488 	}
489 
490  done:
491 	rc = out_obj->buffer.length / REGS_PER_GTF;
492 	if (gtf) {
493 		*gtf = (void *)out_obj->buffer.pointer;
494 		if (ata_msg_probe(ap))
495 			ata_dev_dbg(dev, "%s: returning gtf=%p, gtf_count=%d\n",
496 				    __func__, *gtf, rc);
497 	}
498 	return rc;
499 
500  out_free:
501 	ata_acpi_clear_gtf(dev);
502 	return rc;
503 }
504 
505 /**
506  * ata_acpi_gtm_xfermode - determine xfermode from GTM parameter
507  * @dev: target device
508  * @gtm: GTM parameter to use
509  *
510  * Determine xfermask for @dev from @gtm.
511  *
512  * LOCKING:
513  * None.
514  *
515  * RETURNS:
516  * Determined xfermask.
517  */
518 unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev,
519 				    const struct ata_acpi_gtm *gtm)
520 {
521 	unsigned long xfer_mask = 0;
522 	unsigned int type;
523 	int unit;
524 	u8 mode;
525 
526 	/* we always use the 0 slot for crap hardware */
527 	unit = dev->devno;
528 	if (!(gtm->flags & 0x10))
529 		unit = 0;
530 
531 	/* PIO */
532 	mode = ata_timing_cycle2mode(ATA_SHIFT_PIO, gtm->drive[unit].pio);
533 	xfer_mask |= ata_xfer_mode2mask(mode);
534 
535 	/* See if we have MWDMA or UDMA data. We don't bother with
536 	 * MWDMA if UDMA is available as this means the BIOS set UDMA
537 	 * and our error changedown if it works is UDMA to PIO anyway.
538 	 */
539 	if (!(gtm->flags & (1 << (2 * unit))))
540 		type = ATA_SHIFT_MWDMA;
541 	else
542 		type = ATA_SHIFT_UDMA;
543 
544 	mode = ata_timing_cycle2mode(type, gtm->drive[unit].dma);
545 	xfer_mask |= ata_xfer_mode2mask(mode);
546 
547 	return xfer_mask;
548 }
549 EXPORT_SYMBOL_GPL(ata_acpi_gtm_xfermask);
550 
551 /**
552  * ata_acpi_cbl_80wire		-	Check for 80 wire cable
553  * @ap: Port to check
554  * @gtm: GTM data to use
555  *
556  * Return 1 if the @gtm indicates the BIOS selected an 80wire mode.
557  */
558 int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm)
559 {
560 	struct ata_device *dev;
561 
562 	ata_for_each_dev(dev, &ap->link, ENABLED) {
563 		unsigned long xfer_mask, udma_mask;
564 
565 		xfer_mask = ata_acpi_gtm_xfermask(dev, gtm);
566 		ata_unpack_xfermask(xfer_mask, NULL, NULL, &udma_mask);
567 
568 		if (udma_mask & ~ATA_UDMA_MASK_40C)
569 			return 1;
570 	}
571 
572 	return 0;
573 }
574 EXPORT_SYMBOL_GPL(ata_acpi_cbl_80wire);
575 
576 static void ata_acpi_gtf_to_tf(struct ata_device *dev,
577 			       const struct ata_acpi_gtf *gtf,
578 			       struct ata_taskfile *tf)
579 {
580 	ata_tf_init(dev, tf);
581 
582 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
583 	tf->protocol = ATA_PROT_NODATA;
584 	tf->feature = gtf->tf[0];	/* 0x1f1 */
585 	tf->nsect   = gtf->tf[1];	/* 0x1f2 */
586 	tf->lbal    = gtf->tf[2];	/* 0x1f3 */
587 	tf->lbam    = gtf->tf[3];	/* 0x1f4 */
588 	tf->lbah    = gtf->tf[4];	/* 0x1f5 */
589 	tf->device  = gtf->tf[5];	/* 0x1f6 */
590 	tf->command = gtf->tf[6];	/* 0x1f7 */
591 }
592 
593 static int ata_acpi_filter_tf(struct ata_device *dev,
594 			      const struct ata_taskfile *tf,
595 			      const struct ata_taskfile *ptf)
596 {
597 	if (dev->gtf_filter & ATA_ACPI_FILTER_SETXFER) {
598 		/* libata doesn't use ACPI to configure transfer mode.
599 		 * It will only confuse device configuration.  Skip.
600 		 */
601 		if (tf->command == ATA_CMD_SET_FEATURES &&
602 		    tf->feature == SETFEATURES_XFER)
603 			return 1;
604 	}
605 
606 	if (dev->gtf_filter & ATA_ACPI_FILTER_LOCK) {
607 		/* BIOS writers, sorry but we don't wanna lock
608 		 * features unless the user explicitly said so.
609 		 */
610 
611 		/* DEVICE CONFIGURATION FREEZE LOCK */
612 		if (tf->command == ATA_CMD_CONF_OVERLAY &&
613 		    tf->feature == ATA_DCO_FREEZE_LOCK)
614 			return 1;
615 
616 		/* SECURITY FREEZE LOCK */
617 		if (tf->command == ATA_CMD_SEC_FREEZE_LOCK)
618 			return 1;
619 
620 		/* SET MAX LOCK and SET MAX FREEZE LOCK */
621 		if ((!ptf || ptf->command != ATA_CMD_READ_NATIVE_MAX) &&
622 		    tf->command == ATA_CMD_SET_MAX &&
623 		    (tf->feature == ATA_SET_MAX_LOCK ||
624 		     tf->feature == ATA_SET_MAX_FREEZE_LOCK))
625 			return 1;
626 	}
627 
628 	if (tf->command == ATA_CMD_SET_FEATURES &&
629 	    tf->feature == SETFEATURES_SATA_ENABLE) {
630 		/* inhibit enabling DIPM */
631 		if (dev->gtf_filter & ATA_ACPI_FILTER_DIPM &&
632 		    tf->nsect == SATA_DIPM)
633 			return 1;
634 
635 		/* inhibit FPDMA non-zero offset */
636 		if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_OFFSET &&
637 		    (tf->nsect == SATA_FPDMA_OFFSET ||
638 		     tf->nsect == SATA_FPDMA_IN_ORDER))
639 			return 1;
640 
641 		/* inhibit FPDMA auto activation */
642 		if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_AA &&
643 		    tf->nsect == SATA_FPDMA_AA)
644 			return 1;
645 	}
646 
647 	return 0;
648 }
649 
650 /**
651  * ata_acpi_run_tf - send taskfile registers to host controller
652  * @dev: target ATA device
653  * @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)
654  *
655  * Outputs ATA taskfile to standard ATA host controller.
656  * Writes the control, feature, nsect, lbal, lbam, and lbah registers.
657  * Optionally (ATA_TFLAG_LBA48) writes hob_feature, hob_nsect,
658  * hob_lbal, hob_lbam, and hob_lbah.
659  *
660  * This function waits for idle (!BUSY and !DRQ) after writing
661  * registers.  If the control register has a new value, this
662  * function also waits for idle after writing control and before
663  * writing the remaining registers.
664  *
665  * LOCKING:
666  * EH context.
667  *
668  * RETURNS:
669  * 1 if command is executed successfully.  0 if ignored, rejected or
670  * filtered out, -errno on other errors.
671  */
672 static int ata_acpi_run_tf(struct ata_device *dev,
673 			   const struct ata_acpi_gtf *gtf,
674 			   const struct ata_acpi_gtf *prev_gtf)
675 {
676 	struct ata_taskfile *pptf = NULL;
677 	struct ata_taskfile tf, ptf, rtf;
678 	unsigned int err_mask;
679 	const char *level;
680 	const char *descr;
681 	char msg[60];
682 	int rc;
683 
684 	if ((gtf->tf[0] == 0) && (gtf->tf[1] == 0) && (gtf->tf[2] == 0)
685 	    && (gtf->tf[3] == 0) && (gtf->tf[4] == 0) && (gtf->tf[5] == 0)
686 	    && (gtf->tf[6] == 0))
687 		return 0;
688 
689 	ata_acpi_gtf_to_tf(dev, gtf, &tf);
690 	if (prev_gtf) {
691 		ata_acpi_gtf_to_tf(dev, prev_gtf, &ptf);
692 		pptf = &ptf;
693 	}
694 
695 	if (!ata_acpi_filter_tf(dev, &tf, pptf)) {
696 		rtf = tf;
697 		err_mask = ata_exec_internal(dev, &rtf, NULL,
698 					     DMA_NONE, NULL, 0, 0);
699 
700 		switch (err_mask) {
701 		case 0:
702 			level = KERN_DEBUG;
703 			snprintf(msg, sizeof(msg), "succeeded");
704 			rc = 1;
705 			break;
706 
707 		case AC_ERR_DEV:
708 			level = KERN_INFO;
709 			snprintf(msg, sizeof(msg),
710 				 "rejected by device (Stat=0x%02x Err=0x%02x)",
711 				 rtf.command, rtf.feature);
712 			rc = 0;
713 			break;
714 
715 		default:
716 			level = KERN_ERR;
717 			snprintf(msg, sizeof(msg),
718 				 "failed (Emask=0x%x Stat=0x%02x Err=0x%02x)",
719 				 err_mask, rtf.command, rtf.feature);
720 			rc = -EIO;
721 			break;
722 		}
723 	} else {
724 		level = KERN_INFO;
725 		snprintf(msg, sizeof(msg), "filtered out");
726 		rc = 0;
727 	}
728 	descr = ata_get_cmd_descript(tf.command);
729 
730 	ata_dev_printk(dev, level,
731 		       "ACPI cmd %02x/%02x:%02x:%02x:%02x:%02x:%02x (%s) %s\n",
732 		       tf.command, tf.feature, tf.nsect, tf.lbal,
733 		       tf.lbam, tf.lbah, tf.device,
734 		       (descr ? descr : "unknown"), msg);
735 
736 	return rc;
737 }
738 
739 /**
740  * ata_acpi_exec_tfs - get then write drive taskfile settings
741  * @dev: target ATA device
742  * @nr_executed: out parameter for the number of executed commands
743  *
744  * Evaluate _GTF and execute returned taskfiles.
745  *
746  * LOCKING:
747  * EH context.
748  *
749  * RETURNS:
750  * Number of executed taskfiles on success, 0 if _GTF doesn't exist.
751  * -errno on other errors.
752  */
753 static int ata_acpi_exec_tfs(struct ata_device *dev, int *nr_executed)
754 {
755 	struct ata_acpi_gtf *gtf = NULL, *pgtf = NULL;
756 	int gtf_count, i, rc;
757 
758 	/* get taskfiles */
759 	rc = ata_dev_get_GTF(dev, &gtf);
760 	if (rc < 0)
761 		return rc;
762 	gtf_count = rc;
763 
764 	/* execute them */
765 	for (i = 0; i < gtf_count; i++, gtf++) {
766 		rc = ata_acpi_run_tf(dev, gtf, pgtf);
767 		if (rc < 0)
768 			break;
769 		if (rc) {
770 			(*nr_executed)++;
771 			pgtf = gtf;
772 		}
773 	}
774 
775 	ata_acpi_clear_gtf(dev);
776 
777 	if (rc < 0)
778 		return rc;
779 	return 0;
780 }
781 
782 /**
783  * ata_acpi_push_id - send Identify data to drive
784  * @dev: target ATA device
785  *
786  * _SDD ACPI object: for SATA mode only
787  * Must be after Identify (Packet) Device -- uses its data
788  * ATM this function never returns a failure.  It is an optional
789  * method and if it fails for whatever reason, we should still
790  * just keep going.
791  *
792  * LOCKING:
793  * EH context.
794  *
795  * RETURNS:
796  * 0 on success, -ENOENT if _SDD doesn't exist, -errno on failure.
797  */
798 static int ata_acpi_push_id(struct ata_device *dev)
799 {
800 	struct ata_port *ap = dev->link->ap;
801 	acpi_status status;
802 	struct acpi_object_list input;
803 	union acpi_object in_params[1];
804 
805 	if (ata_msg_probe(ap))
806 		ata_dev_dbg(dev, "%s: ix = %d, port#: %d\n",
807 			    __func__, dev->devno, ap->port_no);
808 
809 	/* Give the drive Identify data to the drive via the _SDD method */
810 	/* _SDD: set up input parameters */
811 	input.count = 1;
812 	input.pointer = in_params;
813 	in_params[0].type = ACPI_TYPE_BUFFER;
814 	in_params[0].buffer.length = sizeof(dev->id[0]) * ATA_ID_WORDS;
815 	in_params[0].buffer.pointer = (u8 *)dev->id;
816 	/* Output buffer: _SDD has no output */
817 
818 	/* It's OK for _SDD to be missing too. */
819 	swap_buf_le16(dev->id, ATA_ID_WORDS);
820 	status = acpi_evaluate_object(dev->acpi_handle, "_SDD", &input, NULL);
821 	swap_buf_le16(dev->id, ATA_ID_WORDS);
822 
823 	if (status == AE_NOT_FOUND)
824 		return -ENOENT;
825 
826 	if (ACPI_FAILURE(status)) {
827 		ata_dev_warn(dev, "ACPI _SDD failed (AE 0x%x)\n", status);
828 		return -EIO;
829 	}
830 
831 	return 0;
832 }
833 
834 /**
835  * ata_acpi_on_suspend - ATA ACPI hook called on suspend
836  * @ap: target ATA port
837  *
838  * This function is called when @ap is about to be suspended.  All
839  * devices are already put to sleep but the port_suspend() callback
840  * hasn't been executed yet.  Error return from this function aborts
841  * suspend.
842  *
843  * LOCKING:
844  * EH context.
845  *
846  * RETURNS:
847  * 0 on success, -errno on failure.
848  */
849 int ata_acpi_on_suspend(struct ata_port *ap)
850 {
851 	/* nada */
852 	return 0;
853 }
854 
855 /**
856  * ata_acpi_on_resume - ATA ACPI hook called on resume
857  * @ap: target ATA port
858  *
859  * This function is called when @ap is resumed - right after port
860  * itself is resumed but before any EH action is taken.
861  *
862  * LOCKING:
863  * EH context.
864  */
865 void ata_acpi_on_resume(struct ata_port *ap)
866 {
867 	const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
868 	struct ata_device *dev;
869 
870 	if (ap->acpi_handle && gtm) {
871 		/* _GTM valid */
872 
873 		/* restore timing parameters */
874 		ata_acpi_stm(ap, gtm);
875 
876 		/* _GTF should immediately follow _STM so that it can
877 		 * use values set by _STM.  Cache _GTF result and
878 		 * schedule _GTF.
879 		 */
880 		ata_for_each_dev(dev, &ap->link, ALL) {
881 			ata_acpi_clear_gtf(dev);
882 			if (ata_dev_enabled(dev) &&
883 			    ata_dev_get_GTF(dev, NULL) >= 0)
884 				dev->flags |= ATA_DFLAG_ACPI_PENDING;
885 		}
886 	} else {
887 		/* SATA _GTF needs to be evaulated after _SDD and
888 		 * there's no reason to evaluate IDE _GTF early
889 		 * without _STM.  Clear cache and schedule _GTF.
890 		 */
891 		ata_for_each_dev(dev, &ap->link, ALL) {
892 			ata_acpi_clear_gtf(dev);
893 			if (ata_dev_enabled(dev))
894 				dev->flags |= ATA_DFLAG_ACPI_PENDING;
895 		}
896 	}
897 }
898 
899 /**
900  * ata_acpi_set_state - set the port power state
901  * @ap: target ATA port
902  * @state: state, on/off
903  *
904  * This function executes the _PS0/_PS3 ACPI method to set the power state.
905  * ACPI spec requires _PS0 when IDE power on and _PS3 when power off
906  */
907 void ata_acpi_set_state(struct ata_port *ap, pm_message_t state)
908 {
909 	struct ata_device *dev;
910 
911 	if (!ap->acpi_handle || (ap->flags & ATA_FLAG_ACPI_SATA))
912 		return;
913 
914 	/* channel first and then drives for power on and vica versa
915 	   for power off */
916 	if (state.event == PM_EVENT_ON)
917 		acpi_bus_set_power(ap->acpi_handle, ACPI_STATE_D0);
918 
919 	ata_for_each_dev(dev, &ap->link, ENABLED) {
920 		if (dev->acpi_handle)
921 			acpi_bus_set_power(dev->acpi_handle,
922 				state.event == PM_EVENT_ON ?
923 					ACPI_STATE_D0 : ACPI_STATE_D3);
924 	}
925 	if (state.event != PM_EVENT_ON)
926 		acpi_bus_set_power(ap->acpi_handle, ACPI_STATE_D3);
927 }
928 
929 /**
930  * ata_acpi_on_devcfg - ATA ACPI hook called on device donfiguration
931  * @dev: target ATA device
932  *
933  * This function is called when @dev is about to be configured.
934  * IDENTIFY data might have been modified after this hook is run.
935  *
936  * LOCKING:
937  * EH context.
938  *
939  * RETURNS:
940  * Positive number if IDENTIFY data needs to be refreshed, 0 if not,
941  * -errno on failure.
942  */
943 int ata_acpi_on_devcfg(struct ata_device *dev)
944 {
945 	struct ata_port *ap = dev->link->ap;
946 	struct ata_eh_context *ehc = &ap->link.eh_context;
947 	int acpi_sata = ap->flags & ATA_FLAG_ACPI_SATA;
948 	int nr_executed = 0;
949 	int rc;
950 
951 	if (!dev->acpi_handle)
952 		return 0;
953 
954 	/* do we need to do _GTF? */
955 	if (!(dev->flags & ATA_DFLAG_ACPI_PENDING) &&
956 	    !(acpi_sata && (ehc->i.flags & ATA_EHI_DID_HARDRESET)))
957 		return 0;
958 
959 	/* do _SDD if SATA */
960 	if (acpi_sata) {
961 		rc = ata_acpi_push_id(dev);
962 		if (rc && rc != -ENOENT)
963 			goto acpi_err;
964 	}
965 
966 	/* do _GTF */
967 	rc = ata_acpi_exec_tfs(dev, &nr_executed);
968 	if (rc)
969 		goto acpi_err;
970 
971 	dev->flags &= ~ATA_DFLAG_ACPI_PENDING;
972 
973 	/* refresh IDENTIFY page if any _GTF command has been executed */
974 	if (nr_executed) {
975 		rc = ata_dev_reread_id(dev, 0);
976 		if (rc < 0) {
977 			ata_dev_err(dev,
978 				    "failed to IDENTIFY after ACPI commands\n");
979 			return rc;
980 		}
981 	}
982 
983 	return 0;
984 
985  acpi_err:
986 	/* ignore evaluation failure if we can continue safely */
987 	if (rc == -EINVAL && !nr_executed && !(ap->pflags & ATA_PFLAG_FROZEN))
988 		return 0;
989 
990 	/* fail and let EH retry once more for unknown IO errors */
991 	if (!(dev->flags & ATA_DFLAG_ACPI_FAILED)) {
992 		dev->flags |= ATA_DFLAG_ACPI_FAILED;
993 		return rc;
994 	}
995 
996 	ata_dev_warn(dev, "ACPI: failed the second time, disabled\n");
997 	dev->acpi_handle = NULL;
998 
999 	/* We can safely continue if no _GTF command has been executed
1000 	 * and port is not frozen.
1001 	 */
1002 	if (!nr_executed && !(ap->pflags & ATA_PFLAG_FROZEN))
1003 		return 0;
1004 
1005 	return rc;
1006 }
1007 
1008 /**
1009  * ata_acpi_on_disable - ATA ACPI hook called when a device is disabled
1010  * @dev: target ATA device
1011  *
1012  * This function is called when @dev is about to be disabled.
1013  *
1014  * LOCKING:
1015  * EH context.
1016  */
1017 void ata_acpi_on_disable(struct ata_device *dev)
1018 {
1019 	ata_acpi_clear_gtf(dev);
1020 }
1021