xref: /linux/drivers/ata/libata-acpi.c (revision b7019ac550eb3916f34d79db583e9b7ea2524afa)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * libata-acpi.c
4  * Provides ACPI support for PATA/SATA.
5  *
6  * Copyright (C) 2006 Intel Corp.
7  * Copyright (C) 2006 Randy Dunlap
8  */
9 
10 #include <linux/module.h>
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 <linux/acpi.h>
17 #include <linux/libata.h>
18 #include <linux/pci.h>
19 #include <linux/slab.h>
20 #include <linux/pm_runtime.h>
21 #include <scsi/scsi_device.h>
22 #include "libata.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 static void ata_acpi_clear_gtf(struct ata_device *dev)
37 {
38 	kfree(dev->gtf_cache);
39 	dev->gtf_cache = NULL;
40 }
41 
42 struct ata_acpi_hotplug_context {
43 	struct acpi_hotplug_context hp;
44 	union {
45 		struct ata_port *ap;
46 		struct ata_device *dev;
47 	} data;
48 };
49 
50 #define ata_hotplug_data(context) (container_of((context), struct ata_acpi_hotplug_context, hp)->data)
51 
52 /**
53  * ata_dev_acpi_handle - provide the acpi_handle for an ata_device
54  * @dev: the acpi_handle returned will correspond to this device
55  *
56  * Returns the acpi_handle for the ACPI namespace object corresponding to
57  * the ata_device passed into the function, or NULL if no such object exists
58  * or ACPI is disabled for this device due to consecutive errors.
59  */
60 acpi_handle ata_dev_acpi_handle(struct ata_device *dev)
61 {
62 	return dev->flags & ATA_DFLAG_ACPI_DISABLED ?
63 			NULL : ACPI_HANDLE(&dev->tdev);
64 }
65 
66 /* @ap and @dev are the same as ata_acpi_handle_hotplug() */
67 static void ata_acpi_detach_device(struct ata_port *ap, struct ata_device *dev)
68 {
69 	if (dev)
70 		dev->flags |= ATA_DFLAG_DETACH;
71 	else {
72 		struct ata_link *tlink;
73 		struct ata_device *tdev;
74 
75 		ata_for_each_link(tlink, ap, EDGE)
76 			ata_for_each_dev(tdev, tlink, ALL)
77 				tdev->flags |= ATA_DFLAG_DETACH;
78 	}
79 
80 	ata_port_schedule_eh(ap);
81 }
82 
83 /**
84  * ata_acpi_handle_hotplug - ACPI event handler backend
85  * @ap: ATA port ACPI event occurred
86  * @dev: ATA device ACPI event occurred (can be NULL)
87  * @event: ACPI event which occurred
88  *
89  * All ACPI bay / device realted events end up in this function.  If
90  * the event is port-wide @dev is NULL.  If the event is specific to a
91  * device, @dev points to it.
92  *
93  * Hotplug (as opposed to unplug) notification is always handled as
94  * port-wide while unplug only kills the target device on device-wide
95  * event.
96  *
97  * LOCKING:
98  * ACPI notify handler context.  May sleep.
99  */
100 static void ata_acpi_handle_hotplug(struct ata_port *ap, struct ata_device *dev,
101 				    u32 event)
102 {
103 	struct ata_eh_info *ehi = &ap->link.eh_info;
104 	int wait = 0;
105 	unsigned long flags;
106 
107 	spin_lock_irqsave(ap->lock, flags);
108 	/*
109 	 * When dock driver calls into the routine, it will always use
110 	 * ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
111 	 * ACPI_NOTIFY_EJECT_REQUEST for remove
112 	 */
113 	switch (event) {
114 	case ACPI_NOTIFY_BUS_CHECK:
115 	case ACPI_NOTIFY_DEVICE_CHECK:
116 		ata_ehi_push_desc(ehi, "ACPI event");
117 
118 		ata_ehi_hotplugged(ehi);
119 		ata_port_freeze(ap);
120 		break;
121 	case ACPI_NOTIFY_EJECT_REQUEST:
122 		ata_ehi_push_desc(ehi, "ACPI event");
123 
124 		ata_acpi_detach_device(ap, dev);
125 		wait = 1;
126 		break;
127 	}
128 
129 	spin_unlock_irqrestore(ap->lock, flags);
130 
131 	if (wait)
132 		ata_port_wait_eh(ap);
133 }
134 
135 static int ata_acpi_dev_notify_dock(struct acpi_device *adev, u32 event)
136 {
137 	struct ata_device *dev = ata_hotplug_data(adev->hp).dev;
138 	ata_acpi_handle_hotplug(dev->link->ap, dev, event);
139 	return 0;
140 }
141 
142 static int ata_acpi_ap_notify_dock(struct acpi_device *adev, u32 event)
143 {
144 	ata_acpi_handle_hotplug(ata_hotplug_data(adev->hp).ap, NULL, event);
145 	return 0;
146 }
147 
148 static void ata_acpi_uevent(struct ata_port *ap, struct ata_device *dev,
149 	u32 event)
150 {
151 	struct kobject *kobj = NULL;
152 	char event_string[20];
153 	char *envp[] = { event_string, NULL };
154 
155 	if (dev) {
156 		if (dev->sdev)
157 			kobj = &dev->sdev->sdev_gendev.kobj;
158 	} else
159 		kobj = &ap->dev->kobj;
160 
161 	if (kobj) {
162 		snprintf(event_string, 20, "BAY_EVENT=%d", event);
163 		kobject_uevent_env(kobj, KOBJ_CHANGE, envp);
164 	}
165 }
166 
167 static void ata_acpi_ap_uevent(struct acpi_device *adev, u32 event)
168 {
169 	ata_acpi_uevent(ata_hotplug_data(adev->hp).ap, NULL, event);
170 }
171 
172 static void ata_acpi_dev_uevent(struct acpi_device *adev, u32 event)
173 {
174 	struct ata_device *dev = ata_hotplug_data(adev->hp).dev;
175 	ata_acpi_uevent(dev->link->ap, dev, event);
176 }
177 
178 /* bind acpi handle to pata port */
179 void ata_acpi_bind_port(struct ata_port *ap)
180 {
181 	struct acpi_device *host_companion = ACPI_COMPANION(ap->host->dev);
182 	struct acpi_device *adev;
183 	struct ata_acpi_hotplug_context *context;
184 
185 	if (libata_noacpi || ap->flags & ATA_FLAG_ACPI_SATA || !host_companion)
186 		return;
187 
188 	acpi_preset_companion(&ap->tdev, host_companion, ap->port_no);
189 
190 	if (ata_acpi_gtm(ap, &ap->__acpi_init_gtm) == 0)
191 		ap->pflags |= ATA_PFLAG_INIT_GTM_VALID;
192 
193 	adev = ACPI_COMPANION(&ap->tdev);
194 	if (!adev || adev->hp)
195 		return;
196 
197 	context = kzalloc(sizeof(*context), GFP_KERNEL);
198 	if (!context)
199 		return;
200 
201 	context->data.ap = ap;
202 	acpi_initialize_hp_context(adev, &context->hp, ata_acpi_ap_notify_dock,
203 				   ata_acpi_ap_uevent);
204 }
205 
206 void ata_acpi_bind_dev(struct ata_device *dev)
207 {
208 	struct ata_port *ap = dev->link->ap;
209 	struct acpi_device *port_companion = ACPI_COMPANION(&ap->tdev);
210 	struct acpi_device *host_companion = ACPI_COMPANION(ap->host->dev);
211 	struct acpi_device *parent, *adev;
212 	struct ata_acpi_hotplug_context *context;
213 	u64 adr;
214 
215 	/*
216 	 * For both sata/pata devices, host companion device is required.
217 	 * For pata device, port companion device is also required.
218 	 */
219 	if (libata_noacpi || !host_companion ||
220 			(!(ap->flags & ATA_FLAG_ACPI_SATA) && !port_companion))
221 		return;
222 
223 	if (ap->flags & ATA_FLAG_ACPI_SATA) {
224 		if (!sata_pmp_attached(ap))
225 			adr = SATA_ADR(ap->port_no, NO_PORT_MULT);
226 		else
227 			adr = SATA_ADR(ap->port_no, dev->link->pmp);
228 		parent = host_companion;
229 	} else {
230 		adr = dev->devno;
231 		parent = port_companion;
232 	}
233 
234 	acpi_preset_companion(&dev->tdev, parent, adr);
235 	adev = ACPI_COMPANION(&dev->tdev);
236 	if (!adev || adev->hp)
237 		return;
238 
239 	context = kzalloc(sizeof(*context), GFP_KERNEL);
240 	if (!context)
241 		return;
242 
243 	context->data.dev = dev;
244 	acpi_initialize_hp_context(adev, &context->hp, ata_acpi_dev_notify_dock,
245 				   ata_acpi_dev_uevent);
246 }
247 
248 /**
249  * ata_acpi_dissociate - dissociate ATA host from ACPI objects
250  * @host: target ATA host
251  *
252  * This function is called during driver detach after the whole host
253  * is shut down.
254  *
255  * LOCKING:
256  * EH context.
257  */
258 void ata_acpi_dissociate(struct ata_host *host)
259 {
260 	int i;
261 
262 	/* Restore initial _GTM values so that driver which attaches
263 	 * afterward can use them too.
264 	 */
265 	for (i = 0; i < host->n_ports; i++) {
266 		struct ata_port *ap = host->ports[i];
267 		const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
268 
269 		if (ACPI_HANDLE(&ap->tdev) && gtm)
270 			ata_acpi_stm(ap, gtm);
271 	}
272 }
273 
274 /**
275  * ata_acpi_gtm - execute _GTM
276  * @ap: target ATA port
277  * @gtm: out parameter for _GTM result
278  *
279  * Evaluate _GTM and store the result in @gtm.
280  *
281  * LOCKING:
282  * EH context.
283  *
284  * RETURNS:
285  * 0 on success, -ENOENT if _GTM doesn't exist, -errno on failure.
286  */
287 int ata_acpi_gtm(struct ata_port *ap, struct ata_acpi_gtm *gtm)
288 {
289 	struct acpi_buffer output = { .length = ACPI_ALLOCATE_BUFFER };
290 	union acpi_object *out_obj;
291 	acpi_status status;
292 	int rc = 0;
293 	acpi_handle handle = ACPI_HANDLE(&ap->tdev);
294 
295 	if (!handle)
296 		return -EINVAL;
297 
298 	status = acpi_evaluate_object(handle, "_GTM", NULL, &output);
299 
300 	rc = -ENOENT;
301 	if (status == AE_NOT_FOUND)
302 		goto out_free;
303 
304 	rc = -EINVAL;
305 	if (ACPI_FAILURE(status)) {
306 		ata_port_err(ap, "ACPI get timing mode failed (AE 0x%x)\n",
307 			     status);
308 		goto out_free;
309 	}
310 
311 	out_obj = output.pointer;
312 	if (out_obj->type != ACPI_TYPE_BUFFER) {
313 		ata_port_warn(ap, "_GTM returned unexpected object type 0x%x\n",
314 			      out_obj->type);
315 
316 		goto out_free;
317 	}
318 
319 	if (out_obj->buffer.length != sizeof(struct ata_acpi_gtm)) {
320 		ata_port_err(ap, "_GTM returned invalid length %d\n",
321 			     out_obj->buffer.length);
322 		goto out_free;
323 	}
324 
325 	memcpy(gtm, out_obj->buffer.pointer, sizeof(struct ata_acpi_gtm));
326 	rc = 0;
327  out_free:
328 	kfree(output.pointer);
329 	return rc;
330 }
331 
332 EXPORT_SYMBOL_GPL(ata_acpi_gtm);
333 
334 /**
335  * ata_acpi_stm - execute _STM
336  * @ap: target ATA port
337  * @stm: timing parameter to _STM
338  *
339  * Evaluate _STM with timing parameter @stm.
340  *
341  * LOCKING:
342  * EH context.
343  *
344  * RETURNS:
345  * 0 on success, -ENOENT if _STM doesn't exist, -errno on failure.
346  */
347 int ata_acpi_stm(struct ata_port *ap, const struct ata_acpi_gtm *stm)
348 {
349 	acpi_status status;
350 	struct ata_acpi_gtm		stm_buf = *stm;
351 	struct acpi_object_list         input;
352 	union acpi_object               in_params[3];
353 
354 	in_params[0].type = ACPI_TYPE_BUFFER;
355 	in_params[0].buffer.length = sizeof(struct ata_acpi_gtm);
356 	in_params[0].buffer.pointer = (u8 *)&stm_buf;
357 	/* Buffers for id may need byteswapping ? */
358 	in_params[1].type = ACPI_TYPE_BUFFER;
359 	in_params[1].buffer.length = 512;
360 	in_params[1].buffer.pointer = (u8 *)ap->link.device[0].id;
361 	in_params[2].type = ACPI_TYPE_BUFFER;
362 	in_params[2].buffer.length = 512;
363 	in_params[2].buffer.pointer = (u8 *)ap->link.device[1].id;
364 
365 	input.count = 3;
366 	input.pointer = in_params;
367 
368 	status = acpi_evaluate_object(ACPI_HANDLE(&ap->tdev), "_STM",
369 				      &input, NULL);
370 
371 	if (status == AE_NOT_FOUND)
372 		return -ENOENT;
373 	if (ACPI_FAILURE(status)) {
374 		ata_port_err(ap, "ACPI set timing mode failed (status=0x%x)\n",
375 			     status);
376 		return -EINVAL;
377 	}
378 	return 0;
379 }
380 
381 EXPORT_SYMBOL_GPL(ata_acpi_stm);
382 
383 /**
384  * ata_dev_get_GTF - get the drive bootup default taskfile settings
385  * @dev: target ATA device
386  * @gtf: output parameter for buffer containing _GTF taskfile arrays
387  *
388  * This applies to both PATA and SATA drives.
389  *
390  * The _GTF method has no input parameters.
391  * It returns a variable number of register set values (registers
392  * hex 1F1..1F7, taskfiles).
393  * The <variable number> is not known in advance, so have ACPI-CA
394  * allocate the buffer as needed and return it, then free it later.
395  *
396  * LOCKING:
397  * EH context.
398  *
399  * RETURNS:
400  * Number of taskfiles on success, 0 if _GTF doesn't exist.  -EINVAL
401  * if _GTF is invalid.
402  */
403 static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf)
404 {
405 	struct ata_port *ap = dev->link->ap;
406 	acpi_status status;
407 	struct acpi_buffer output;
408 	union acpi_object *out_obj;
409 	int rc = 0;
410 
411 	/* if _GTF is cached, use the cached value */
412 	if (dev->gtf_cache) {
413 		out_obj = dev->gtf_cache;
414 		goto done;
415 	}
416 
417 	/* set up output buffer */
418 	output.length = ACPI_ALLOCATE_BUFFER;
419 	output.pointer = NULL;	/* ACPI-CA sets this; save/free it later */
420 
421 	if (ata_msg_probe(ap))
422 		ata_dev_dbg(dev, "%s: ENTER: port#: %d\n",
423 			    __func__, ap->port_no);
424 
425 	/* _GTF has no input parameters */
426 	status = acpi_evaluate_object(ata_dev_acpi_handle(dev), "_GTF", NULL,
427 				      &output);
428 	out_obj = dev->gtf_cache = output.pointer;
429 
430 	if (ACPI_FAILURE(status)) {
431 		if (status != AE_NOT_FOUND) {
432 			ata_dev_warn(dev, "_GTF evaluation failed (AE 0x%x)\n",
433 				     status);
434 			rc = -EINVAL;
435 		}
436 		goto out_free;
437 	}
438 
439 	if (!output.length || !output.pointer) {
440 		if (ata_msg_probe(ap))
441 			ata_dev_dbg(dev, "%s: Run _GTF: length or ptr is NULL (0x%llx, 0x%p)\n",
442 				    __func__,
443 				    (unsigned long long)output.length,
444 				    output.pointer);
445 		rc = -EINVAL;
446 		goto out_free;
447 	}
448 
449 	if (out_obj->type != ACPI_TYPE_BUFFER) {
450 		ata_dev_warn(dev, "_GTF unexpected object type 0x%x\n",
451 			     out_obj->type);
452 		rc = -EINVAL;
453 		goto out_free;
454 	}
455 
456 	if (out_obj->buffer.length % REGS_PER_GTF) {
457 		ata_dev_warn(dev, "unexpected _GTF length (%d)\n",
458 			     out_obj->buffer.length);
459 		rc = -EINVAL;
460 		goto out_free;
461 	}
462 
463  done:
464 	rc = out_obj->buffer.length / REGS_PER_GTF;
465 	if (gtf) {
466 		*gtf = (void *)out_obj->buffer.pointer;
467 		if (ata_msg_probe(ap))
468 			ata_dev_dbg(dev, "%s: returning gtf=%p, gtf_count=%d\n",
469 				    __func__, *gtf, rc);
470 	}
471 	return rc;
472 
473  out_free:
474 	ata_acpi_clear_gtf(dev);
475 	return rc;
476 }
477 
478 /**
479  * ata_acpi_gtm_xfermode - determine xfermode from GTM parameter
480  * @dev: target device
481  * @gtm: GTM parameter to use
482  *
483  * Determine xfermask for @dev from @gtm.
484  *
485  * LOCKING:
486  * None.
487  *
488  * RETURNS:
489  * Determined xfermask.
490  */
491 unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev,
492 				    const struct ata_acpi_gtm *gtm)
493 {
494 	unsigned long xfer_mask = 0;
495 	unsigned int type;
496 	int unit;
497 	u8 mode;
498 
499 	/* we always use the 0 slot for crap hardware */
500 	unit = dev->devno;
501 	if (!(gtm->flags & 0x10))
502 		unit = 0;
503 
504 	/* PIO */
505 	mode = ata_timing_cycle2mode(ATA_SHIFT_PIO, gtm->drive[unit].pio);
506 	xfer_mask |= ata_xfer_mode2mask(mode);
507 
508 	/* See if we have MWDMA or UDMA data. We don't bother with
509 	 * MWDMA if UDMA is available as this means the BIOS set UDMA
510 	 * and our error changedown if it works is UDMA to PIO anyway.
511 	 */
512 	if (!(gtm->flags & (1 << (2 * unit))))
513 		type = ATA_SHIFT_MWDMA;
514 	else
515 		type = ATA_SHIFT_UDMA;
516 
517 	mode = ata_timing_cycle2mode(type, gtm->drive[unit].dma);
518 	xfer_mask |= ata_xfer_mode2mask(mode);
519 
520 	return xfer_mask;
521 }
522 EXPORT_SYMBOL_GPL(ata_acpi_gtm_xfermask);
523 
524 /**
525  * ata_acpi_cbl_80wire		-	Check for 80 wire cable
526  * @ap: Port to check
527  * @gtm: GTM data to use
528  *
529  * Return 1 if the @gtm indicates the BIOS selected an 80wire mode.
530  */
531 int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm)
532 {
533 	struct ata_device *dev;
534 
535 	ata_for_each_dev(dev, &ap->link, ENABLED) {
536 		unsigned long xfer_mask, udma_mask;
537 
538 		xfer_mask = ata_acpi_gtm_xfermask(dev, gtm);
539 		ata_unpack_xfermask(xfer_mask, NULL, NULL, &udma_mask);
540 
541 		if (udma_mask & ~ATA_UDMA_MASK_40C)
542 			return 1;
543 	}
544 
545 	return 0;
546 }
547 EXPORT_SYMBOL_GPL(ata_acpi_cbl_80wire);
548 
549 static void ata_acpi_gtf_to_tf(struct ata_device *dev,
550 			       const struct ata_acpi_gtf *gtf,
551 			       struct ata_taskfile *tf)
552 {
553 	ata_tf_init(dev, tf);
554 
555 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
556 	tf->protocol = ATA_PROT_NODATA;
557 	tf->feature = gtf->tf[0];	/* 0x1f1 */
558 	tf->nsect   = gtf->tf[1];	/* 0x1f2 */
559 	tf->lbal    = gtf->tf[2];	/* 0x1f3 */
560 	tf->lbam    = gtf->tf[3];	/* 0x1f4 */
561 	tf->lbah    = gtf->tf[4];	/* 0x1f5 */
562 	tf->device  = gtf->tf[5];	/* 0x1f6 */
563 	tf->command = gtf->tf[6];	/* 0x1f7 */
564 }
565 
566 static int ata_acpi_filter_tf(struct ata_device *dev,
567 			      const struct ata_taskfile *tf,
568 			      const struct ata_taskfile *ptf)
569 {
570 	if (dev->gtf_filter & ATA_ACPI_FILTER_SETXFER) {
571 		/* libata doesn't use ACPI to configure transfer mode.
572 		 * It will only confuse device configuration.  Skip.
573 		 */
574 		if (tf->command == ATA_CMD_SET_FEATURES &&
575 		    tf->feature == SETFEATURES_XFER)
576 			return 1;
577 	}
578 
579 	if (dev->gtf_filter & ATA_ACPI_FILTER_LOCK) {
580 		/* BIOS writers, sorry but we don't wanna lock
581 		 * features unless the user explicitly said so.
582 		 */
583 
584 		/* DEVICE CONFIGURATION FREEZE LOCK */
585 		if (tf->command == ATA_CMD_CONF_OVERLAY &&
586 		    tf->feature == ATA_DCO_FREEZE_LOCK)
587 			return 1;
588 
589 		/* SECURITY FREEZE LOCK */
590 		if (tf->command == ATA_CMD_SEC_FREEZE_LOCK)
591 			return 1;
592 
593 		/* SET MAX LOCK and SET MAX FREEZE LOCK */
594 		if ((!ptf || ptf->command != ATA_CMD_READ_NATIVE_MAX) &&
595 		    tf->command == ATA_CMD_SET_MAX &&
596 		    (tf->feature == ATA_SET_MAX_LOCK ||
597 		     tf->feature == ATA_SET_MAX_FREEZE_LOCK))
598 			return 1;
599 	}
600 
601 	if (tf->command == ATA_CMD_SET_FEATURES &&
602 	    tf->feature == SETFEATURES_SATA_ENABLE) {
603 		/* inhibit enabling DIPM */
604 		if (dev->gtf_filter & ATA_ACPI_FILTER_DIPM &&
605 		    tf->nsect == SATA_DIPM)
606 			return 1;
607 
608 		/* inhibit FPDMA non-zero offset */
609 		if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_OFFSET &&
610 		    (tf->nsect == SATA_FPDMA_OFFSET ||
611 		     tf->nsect == SATA_FPDMA_IN_ORDER))
612 			return 1;
613 
614 		/* inhibit FPDMA auto activation */
615 		if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_AA &&
616 		    tf->nsect == SATA_FPDMA_AA)
617 			return 1;
618 	}
619 
620 	return 0;
621 }
622 
623 /**
624  * ata_acpi_run_tf - send taskfile registers to host controller
625  * @dev: target ATA device
626  * @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)
627  *
628  * Outputs ATA taskfile to standard ATA host controller.
629  * Writes the control, feature, nsect, lbal, lbam, and lbah registers.
630  * Optionally (ATA_TFLAG_LBA48) writes hob_feature, hob_nsect,
631  * hob_lbal, hob_lbam, and hob_lbah.
632  *
633  * This function waits for idle (!BUSY and !DRQ) after writing
634  * registers.  If the control register has a new value, this
635  * function also waits for idle after writing control and before
636  * writing the remaining registers.
637  *
638  * LOCKING:
639  * EH context.
640  *
641  * RETURNS:
642  * 1 if command is executed successfully.  0 if ignored, rejected or
643  * filtered out, -errno on other errors.
644  */
645 static int ata_acpi_run_tf(struct ata_device *dev,
646 			   const struct ata_acpi_gtf *gtf,
647 			   const struct ata_acpi_gtf *prev_gtf)
648 {
649 	struct ata_taskfile *pptf = NULL;
650 	struct ata_taskfile tf, ptf, rtf;
651 	unsigned int err_mask;
652 	const char *level;
653 	const char *descr;
654 	char msg[60];
655 	int rc;
656 
657 	if ((gtf->tf[0] == 0) && (gtf->tf[1] == 0) && (gtf->tf[2] == 0)
658 	    && (gtf->tf[3] == 0) && (gtf->tf[4] == 0) && (gtf->tf[5] == 0)
659 	    && (gtf->tf[6] == 0))
660 		return 0;
661 
662 	ata_acpi_gtf_to_tf(dev, gtf, &tf);
663 	if (prev_gtf) {
664 		ata_acpi_gtf_to_tf(dev, prev_gtf, &ptf);
665 		pptf = &ptf;
666 	}
667 
668 	if (!ata_acpi_filter_tf(dev, &tf, pptf)) {
669 		rtf = tf;
670 		err_mask = ata_exec_internal(dev, &rtf, NULL,
671 					     DMA_NONE, NULL, 0, 0);
672 
673 		switch (err_mask) {
674 		case 0:
675 			level = KERN_DEBUG;
676 			snprintf(msg, sizeof(msg), "succeeded");
677 			rc = 1;
678 			break;
679 
680 		case AC_ERR_DEV:
681 			level = KERN_INFO;
682 			snprintf(msg, sizeof(msg),
683 				 "rejected by device (Stat=0x%02x Err=0x%02x)",
684 				 rtf.command, rtf.feature);
685 			rc = 0;
686 			break;
687 
688 		default:
689 			level = KERN_ERR;
690 			snprintf(msg, sizeof(msg),
691 				 "failed (Emask=0x%x Stat=0x%02x Err=0x%02x)",
692 				 err_mask, rtf.command, rtf.feature);
693 			rc = -EIO;
694 			break;
695 		}
696 	} else {
697 		level = KERN_INFO;
698 		snprintf(msg, sizeof(msg), "filtered out");
699 		rc = 0;
700 	}
701 	descr = ata_get_cmd_descript(tf.command);
702 
703 	ata_dev_printk(dev, level,
704 		       "ACPI cmd %02x/%02x:%02x:%02x:%02x:%02x:%02x (%s) %s\n",
705 		       tf.command, tf.feature, tf.nsect, tf.lbal,
706 		       tf.lbam, tf.lbah, tf.device,
707 		       (descr ? descr : "unknown"), msg);
708 
709 	return rc;
710 }
711 
712 /**
713  * ata_acpi_exec_tfs - get then write drive taskfile settings
714  * @dev: target ATA device
715  * @nr_executed: out parameter for the number of executed commands
716  *
717  * Evaluate _GTF and execute returned taskfiles.
718  *
719  * LOCKING:
720  * EH context.
721  *
722  * RETURNS:
723  * Number of executed taskfiles on success, 0 if _GTF doesn't exist.
724  * -errno on other errors.
725  */
726 static int ata_acpi_exec_tfs(struct ata_device *dev, int *nr_executed)
727 {
728 	struct ata_acpi_gtf *gtf = NULL, *pgtf = NULL;
729 	int gtf_count, i, rc;
730 
731 	/* get taskfiles */
732 	rc = ata_dev_get_GTF(dev, &gtf);
733 	if (rc < 0)
734 		return rc;
735 	gtf_count = rc;
736 
737 	/* execute them */
738 	for (i = 0; i < gtf_count; i++, gtf++) {
739 		rc = ata_acpi_run_tf(dev, gtf, pgtf);
740 		if (rc < 0)
741 			break;
742 		if (rc) {
743 			(*nr_executed)++;
744 			pgtf = gtf;
745 		}
746 	}
747 
748 	ata_acpi_clear_gtf(dev);
749 
750 	if (rc < 0)
751 		return rc;
752 	return 0;
753 }
754 
755 /**
756  * ata_acpi_push_id - send Identify data to drive
757  * @dev: target ATA device
758  *
759  * _SDD ACPI object: for SATA mode only
760  * Must be after Identify (Packet) Device -- uses its data
761  * ATM this function never returns a failure.  It is an optional
762  * method and if it fails for whatever reason, we should still
763  * just keep going.
764  *
765  * LOCKING:
766  * EH context.
767  *
768  * RETURNS:
769  * 0 on success, -ENOENT if _SDD doesn't exist, -errno on failure.
770  */
771 static int ata_acpi_push_id(struct ata_device *dev)
772 {
773 	struct ata_port *ap = dev->link->ap;
774 	acpi_status status;
775 	struct acpi_object_list input;
776 	union acpi_object in_params[1];
777 
778 	if (ata_msg_probe(ap))
779 		ata_dev_dbg(dev, "%s: ix = %d, port#: %d\n",
780 			    __func__, dev->devno, ap->port_no);
781 
782 	/* Give the drive Identify data to the drive via the _SDD method */
783 	/* _SDD: set up input parameters */
784 	input.count = 1;
785 	input.pointer = in_params;
786 	in_params[0].type = ACPI_TYPE_BUFFER;
787 	in_params[0].buffer.length = sizeof(dev->id[0]) * ATA_ID_WORDS;
788 	in_params[0].buffer.pointer = (u8 *)dev->id;
789 	/* Output buffer: _SDD has no output */
790 
791 	/* It's OK for _SDD to be missing too. */
792 	swap_buf_le16(dev->id, ATA_ID_WORDS);
793 	status = acpi_evaluate_object(ata_dev_acpi_handle(dev), "_SDD", &input,
794 				      NULL);
795 	swap_buf_le16(dev->id, ATA_ID_WORDS);
796 
797 	if (status == AE_NOT_FOUND)
798 		return -ENOENT;
799 
800 	if (ACPI_FAILURE(status)) {
801 		ata_dev_warn(dev, "ACPI _SDD failed (AE 0x%x)\n", status);
802 		return -EIO;
803 	}
804 
805 	return 0;
806 }
807 
808 /**
809  * ata_acpi_on_suspend - ATA ACPI hook called on suspend
810  * @ap: target ATA port
811  *
812  * This function is called when @ap is about to be suspended.  All
813  * devices are already put to sleep but the port_suspend() callback
814  * hasn't been executed yet.  Error return from this function aborts
815  * suspend.
816  *
817  * LOCKING:
818  * EH context.
819  *
820  * RETURNS:
821  * 0 on success, -errno on failure.
822  */
823 int ata_acpi_on_suspend(struct ata_port *ap)
824 {
825 	/* nada */
826 	return 0;
827 }
828 
829 /**
830  * ata_acpi_on_resume - ATA ACPI hook called on resume
831  * @ap: target ATA port
832  *
833  * This function is called when @ap is resumed - right after port
834  * itself is resumed but before any EH action is taken.
835  *
836  * LOCKING:
837  * EH context.
838  */
839 void ata_acpi_on_resume(struct ata_port *ap)
840 {
841 	const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
842 	struct ata_device *dev;
843 
844 	if (ACPI_HANDLE(&ap->tdev) && gtm) {
845 		/* _GTM valid */
846 
847 		/* restore timing parameters */
848 		ata_acpi_stm(ap, gtm);
849 
850 		/* _GTF should immediately follow _STM so that it can
851 		 * use values set by _STM.  Cache _GTF result and
852 		 * schedule _GTF.
853 		 */
854 		ata_for_each_dev(dev, &ap->link, ALL) {
855 			ata_acpi_clear_gtf(dev);
856 			if (ata_dev_enabled(dev) &&
857 			    ata_dev_acpi_handle(dev) &&
858 			    ata_dev_get_GTF(dev, NULL) >= 0)
859 				dev->flags |= ATA_DFLAG_ACPI_PENDING;
860 		}
861 	} else {
862 		/* SATA _GTF needs to be evaulated after _SDD and
863 		 * there's no reason to evaluate IDE _GTF early
864 		 * without _STM.  Clear cache and schedule _GTF.
865 		 */
866 		ata_for_each_dev(dev, &ap->link, ALL) {
867 			ata_acpi_clear_gtf(dev);
868 			if (ata_dev_enabled(dev))
869 				dev->flags |= ATA_DFLAG_ACPI_PENDING;
870 		}
871 	}
872 }
873 
874 static int ata_acpi_choose_suspend_state(struct ata_device *dev, bool runtime)
875 {
876 	int d_max_in = ACPI_STATE_D3_COLD;
877 	if (!runtime)
878 		goto out;
879 
880 	/*
881 	 * For ATAPI, runtime D3 cold is only allowed
882 	 * for ZPODD in zero power ready state
883 	 */
884 	if (dev->class == ATA_DEV_ATAPI &&
885 	    !(zpodd_dev_enabled(dev) && zpodd_zpready(dev)))
886 		d_max_in = ACPI_STATE_D3_HOT;
887 
888 out:
889 	return acpi_pm_device_sleep_state(&dev->tdev, NULL, d_max_in);
890 }
891 
892 static void sata_acpi_set_state(struct ata_port *ap, pm_message_t state)
893 {
894 	bool runtime = PMSG_IS_AUTO(state);
895 	struct ata_device *dev;
896 	acpi_handle handle;
897 	int acpi_state;
898 
899 	ata_for_each_dev(dev, &ap->link, ENABLED) {
900 		handle = ata_dev_acpi_handle(dev);
901 		if (!handle)
902 			continue;
903 
904 		if (!(state.event & PM_EVENT_RESUME)) {
905 			acpi_state = ata_acpi_choose_suspend_state(dev, runtime);
906 			if (acpi_state == ACPI_STATE_D0)
907 				continue;
908 			if (runtime && zpodd_dev_enabled(dev) &&
909 			    acpi_state == ACPI_STATE_D3_COLD)
910 				zpodd_enable_run_wake(dev);
911 			acpi_bus_set_power(handle, acpi_state);
912 		} else {
913 			if (runtime && zpodd_dev_enabled(dev))
914 				zpodd_disable_run_wake(dev);
915 			acpi_bus_set_power(handle, ACPI_STATE_D0);
916 		}
917 	}
918 }
919 
920 /* ACPI spec requires _PS0 when IDE power on and _PS3 when power off */
921 static void pata_acpi_set_state(struct ata_port *ap, pm_message_t state)
922 {
923 	struct ata_device *dev;
924 	acpi_handle port_handle;
925 
926 	port_handle = ACPI_HANDLE(&ap->tdev);
927 	if (!port_handle)
928 		return;
929 
930 	/* channel first and then drives for power on and vica versa
931 	   for power off */
932 	if (state.event & PM_EVENT_RESUME)
933 		acpi_bus_set_power(port_handle, ACPI_STATE_D0);
934 
935 	ata_for_each_dev(dev, &ap->link, ENABLED) {
936 		acpi_handle dev_handle = ata_dev_acpi_handle(dev);
937 		if (!dev_handle)
938 			continue;
939 
940 		acpi_bus_set_power(dev_handle, state.event & PM_EVENT_RESUME ?
941 					ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
942 	}
943 
944 	if (!(state.event & PM_EVENT_RESUME))
945 		acpi_bus_set_power(port_handle, ACPI_STATE_D3_COLD);
946 }
947 
948 /**
949  * ata_acpi_set_state - set the port power state
950  * @ap: target ATA port
951  * @state: state, on/off
952  *
953  * This function sets a proper ACPI D state for the device on
954  * system and runtime PM operations.
955  */
956 void ata_acpi_set_state(struct ata_port *ap, pm_message_t state)
957 {
958 	if (ap->flags & ATA_FLAG_ACPI_SATA)
959 		sata_acpi_set_state(ap, state);
960 	else
961 		pata_acpi_set_state(ap, state);
962 }
963 
964 /**
965  * ata_acpi_on_devcfg - ATA ACPI hook called on device donfiguration
966  * @dev: target ATA device
967  *
968  * This function is called when @dev is about to be configured.
969  * IDENTIFY data might have been modified after this hook is run.
970  *
971  * LOCKING:
972  * EH context.
973  *
974  * RETURNS:
975  * Positive number if IDENTIFY data needs to be refreshed, 0 if not,
976  * -errno on failure.
977  */
978 int ata_acpi_on_devcfg(struct ata_device *dev)
979 {
980 	struct ata_port *ap = dev->link->ap;
981 	struct ata_eh_context *ehc = &ap->link.eh_context;
982 	int acpi_sata = ap->flags & ATA_FLAG_ACPI_SATA;
983 	int nr_executed = 0;
984 	int rc;
985 
986 	if (!ata_dev_acpi_handle(dev))
987 		return 0;
988 
989 	/* do we need to do _GTF? */
990 	if (!(dev->flags & ATA_DFLAG_ACPI_PENDING) &&
991 	    !(acpi_sata && (ehc->i.flags & ATA_EHI_DID_HARDRESET)))
992 		return 0;
993 
994 	/* do _SDD if SATA */
995 	if (acpi_sata) {
996 		rc = ata_acpi_push_id(dev);
997 		if (rc && rc != -ENOENT)
998 			goto acpi_err;
999 	}
1000 
1001 	/* do _GTF */
1002 	rc = ata_acpi_exec_tfs(dev, &nr_executed);
1003 	if (rc)
1004 		goto acpi_err;
1005 
1006 	dev->flags &= ~ATA_DFLAG_ACPI_PENDING;
1007 
1008 	/* refresh IDENTIFY page if any _GTF command has been executed */
1009 	if (nr_executed) {
1010 		rc = ata_dev_reread_id(dev, 0);
1011 		if (rc < 0) {
1012 			ata_dev_err(dev,
1013 				    "failed to IDENTIFY after ACPI commands\n");
1014 			return rc;
1015 		}
1016 	}
1017 
1018 	return 0;
1019 
1020  acpi_err:
1021 	/* ignore evaluation failure if we can continue safely */
1022 	if (rc == -EINVAL && !nr_executed && !(ap->pflags & ATA_PFLAG_FROZEN))
1023 		return 0;
1024 
1025 	/* fail and let EH retry once more for unknown IO errors */
1026 	if (!(dev->flags & ATA_DFLAG_ACPI_FAILED)) {
1027 		dev->flags |= ATA_DFLAG_ACPI_FAILED;
1028 		return rc;
1029 	}
1030 
1031 	dev->flags |= ATA_DFLAG_ACPI_DISABLED;
1032 	ata_dev_warn(dev, "ACPI: failed the second time, disabled\n");
1033 
1034 	/* We can safely continue if no _GTF command has been executed
1035 	 * and port is not frozen.
1036 	 */
1037 	if (!nr_executed && !(ap->pflags & ATA_PFLAG_FROZEN))
1038 		return 0;
1039 
1040 	return rc;
1041 }
1042 
1043 /**
1044  * ata_acpi_on_disable - ATA ACPI hook called when a device is disabled
1045  * @dev: target ATA device
1046  *
1047  * This function is called when @dev is about to be disabled.
1048  *
1049  * LOCKING:
1050  * EH context.
1051  */
1052 void ata_acpi_on_disable(struct ata_device *dev)
1053 {
1054 	ata_acpi_clear_gtf(dev);
1055 }
1056