xref: /linux/drivers/pci/pci-acpi.c (revision 46e6acfe3501fa938af9c5bd730f0020235b08a2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PCI support in ACPI
4  *
5  * Copyright (C) 2005 David Shaohua Li <shaohua.li@intel.com>
6  * Copyright (C) 2004 Tom Long Nguyen <tom.l.nguyen@intel.com>
7  * Copyright (C) 2004 Intel Corp.
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/irqdomain.h>
13 #include <linux/pci.h>
14 #include <linux/msi.h>
15 #include <linux/pci_hotplug.h>
16 #include <linux/module.h>
17 #include <linux/pci-acpi.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/pm_qos.h>
20 #include <linux/rwsem.h>
21 #include "pci.h"
22 
23 /*
24  * The GUID is defined in the PCI Firmware Specification available
25  * here to PCI-SIG members:
26  * https://members.pcisig.com/wg/PCI-SIG/document/15350
27  */
28 const guid_t pci_acpi_dsm_guid =
29 	GUID_INIT(0xe5c937d0, 0x3553, 0x4d7a,
30 		  0x91, 0x17, 0xea, 0x4d, 0x19, 0xc3, 0x43, 0x4d);
31 
32 #if defined(CONFIG_PCI_QUIRKS) && defined(CONFIG_ARM64)
33 static int acpi_get_rc_addr(struct acpi_device *adev, struct resource *res)
34 {
35 	struct device *dev = &adev->dev;
36 	struct resource_entry *entry;
37 	struct list_head list;
38 	unsigned long flags;
39 	int ret;
40 
41 	INIT_LIST_HEAD(&list);
42 	flags = IORESOURCE_MEM;
43 	ret = acpi_dev_get_resources(adev, &list,
44 				     acpi_dev_filter_resource_type_cb,
45 				     (void *) flags);
46 	if (ret < 0) {
47 		dev_err(dev, "failed to parse _CRS method, error code %d\n",
48 			ret);
49 		return ret;
50 	}
51 
52 	if (ret == 0) {
53 		dev_err(dev, "no IO and memory resources present in _CRS\n");
54 		return -EINVAL;
55 	}
56 
57 	entry = list_first_entry(&list, struct resource_entry, node);
58 	*res = *entry->res;
59 	acpi_dev_free_resource_list(&list);
60 	return 0;
61 }
62 
63 static acpi_status acpi_match_rc(acpi_handle handle, u32 lvl, void *context,
64 				 void **retval)
65 {
66 	u16 *segment = context;
67 	unsigned long long uid;
68 	acpi_status status;
69 
70 	status = acpi_evaluate_integer(handle, METHOD_NAME__UID, NULL, &uid);
71 	if (ACPI_FAILURE(status) || uid != *segment)
72 		return AE_CTRL_DEPTH;
73 
74 	*(acpi_handle *)retval = handle;
75 	return AE_CTRL_TERMINATE;
76 }
77 
78 int acpi_get_rc_resources(struct device *dev, const char *hid, u16 segment,
79 			  struct resource *res)
80 {
81 	struct acpi_device *adev;
82 	acpi_status status;
83 	acpi_handle handle;
84 	int ret;
85 
86 	status = acpi_get_devices(hid, acpi_match_rc, &segment, &handle);
87 	if (ACPI_FAILURE(status)) {
88 		dev_err(dev, "can't find _HID %s device to locate resources\n",
89 			hid);
90 		return -ENODEV;
91 	}
92 
93 	adev = acpi_fetch_acpi_dev(handle);
94 	if (!adev)
95 		return -ENODEV;
96 
97 	ret = acpi_get_rc_addr(adev, res);
98 	if (ret) {
99 		dev_err(dev, "can't get resource from %s\n",
100 			dev_name(&adev->dev));
101 		return ret;
102 	}
103 
104 	return 0;
105 }
106 #endif
107 
108 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
109 {
110 	acpi_status status = AE_NOT_EXIST;
111 	unsigned long long mcfg_addr;
112 
113 	if (handle)
114 		status = acpi_evaluate_integer(handle, METHOD_NAME__CBA,
115 					       NULL, &mcfg_addr);
116 	if (ACPI_FAILURE(status))
117 		return 0;
118 
119 	return (phys_addr_t)mcfg_addr;
120 }
121 
122 bool pci_acpi_preserve_config(struct pci_host_bridge *host_bridge)
123 {
124 	if (ACPI_HANDLE(&host_bridge->dev)) {
125 		union acpi_object *obj;
126 
127 		/*
128 		 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
129 		 * exists and returns 0, we must preserve any PCI resource
130 		 * assignments made by firmware for this host bridge.
131 		 */
132 		obj = acpi_evaluate_dsm_typed(ACPI_HANDLE(&host_bridge->dev),
133 					      &pci_acpi_dsm_guid,
134 					      1, DSM_PCI_PRESERVE_BOOT_CONFIG,
135 					      NULL, ACPI_TYPE_INTEGER);
136 		if (obj && obj->integer.value == 0)
137 			return true;
138 		ACPI_FREE(obj);
139 	}
140 
141 	return false;
142 }
143 
144 /* _HPX PCI Setting Record (Type 0); same as _HPP */
145 struct hpx_type0 {
146 	u32 revision;		/* Not present in _HPP */
147 	u8  cache_line_size;	/* Not applicable to PCIe */
148 	u8  latency_timer;	/* Not applicable to PCIe */
149 	u8  enable_serr;
150 	u8  enable_perr;
151 };
152 
153 static struct hpx_type0 pci_default_type0 = {
154 	.revision = 1,
155 	.cache_line_size = 8,
156 	.latency_timer = 0x40,
157 	.enable_serr = 0,
158 	.enable_perr = 0,
159 };
160 
161 static void program_hpx_type0(struct pci_dev *dev, struct hpx_type0 *hpx)
162 {
163 	u16 pci_cmd, pci_bctl;
164 
165 	if (!hpx)
166 		hpx = &pci_default_type0;
167 
168 	if (hpx->revision > 1) {
169 		pci_warn(dev, "PCI settings rev %d not supported; using defaults\n",
170 			 hpx->revision);
171 		hpx = &pci_default_type0;
172 	}
173 
174 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpx->cache_line_size);
175 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpx->latency_timer);
176 	pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
177 	if (hpx->enable_serr)
178 		pci_cmd |= PCI_COMMAND_SERR;
179 	if (hpx->enable_perr)
180 		pci_cmd |= PCI_COMMAND_PARITY;
181 	pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
182 
183 	/* Program bridge control value */
184 	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
185 		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
186 				      hpx->latency_timer);
187 		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
188 		if (hpx->enable_perr)
189 			pci_bctl |= PCI_BRIDGE_CTL_PARITY;
190 		pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
191 	}
192 }
193 
194 static acpi_status decode_type0_hpx_record(union acpi_object *record,
195 					   struct hpx_type0 *hpx0)
196 {
197 	int i;
198 	union acpi_object *fields = record->package.elements;
199 	u32 revision = fields[1].integer.value;
200 
201 	switch (revision) {
202 	case 1:
203 		if (record->package.count != 6)
204 			return AE_ERROR;
205 		for (i = 2; i < 6; i++)
206 			if (fields[i].type != ACPI_TYPE_INTEGER)
207 				return AE_ERROR;
208 		hpx0->revision        = revision;
209 		hpx0->cache_line_size = fields[2].integer.value;
210 		hpx0->latency_timer   = fields[3].integer.value;
211 		hpx0->enable_serr     = fields[4].integer.value;
212 		hpx0->enable_perr     = fields[5].integer.value;
213 		break;
214 	default:
215 		pr_warn("%s: Type 0 Revision %d record not supported\n",
216 		       __func__, revision);
217 		return AE_ERROR;
218 	}
219 	return AE_OK;
220 }
221 
222 /* _HPX PCI-X Setting Record (Type 1) */
223 struct hpx_type1 {
224 	u32 revision;
225 	u8  max_mem_read;
226 	u8  avg_max_split;
227 	u16 tot_max_split;
228 };
229 
230 static void program_hpx_type1(struct pci_dev *dev, struct hpx_type1 *hpx)
231 {
232 	int pos;
233 
234 	if (!hpx)
235 		return;
236 
237 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
238 	if (!pos)
239 		return;
240 
241 	pci_warn(dev, "PCI-X settings not supported\n");
242 }
243 
244 static acpi_status decode_type1_hpx_record(union acpi_object *record,
245 					   struct hpx_type1 *hpx1)
246 {
247 	int i;
248 	union acpi_object *fields = record->package.elements;
249 	u32 revision = fields[1].integer.value;
250 
251 	switch (revision) {
252 	case 1:
253 		if (record->package.count != 5)
254 			return AE_ERROR;
255 		for (i = 2; i < 5; i++)
256 			if (fields[i].type != ACPI_TYPE_INTEGER)
257 				return AE_ERROR;
258 		hpx1->revision      = revision;
259 		hpx1->max_mem_read  = fields[2].integer.value;
260 		hpx1->avg_max_split = fields[3].integer.value;
261 		hpx1->tot_max_split = fields[4].integer.value;
262 		break;
263 	default:
264 		pr_warn("%s: Type 1 Revision %d record not supported\n",
265 		       __func__, revision);
266 		return AE_ERROR;
267 	}
268 	return AE_OK;
269 }
270 
271 static bool pcie_root_rcb_set(struct pci_dev *dev)
272 {
273 	struct pci_dev *rp = pcie_find_root_port(dev);
274 	u16 lnkctl;
275 
276 	if (!rp)
277 		return false;
278 
279 	pcie_capability_read_word(rp, PCI_EXP_LNKCTL, &lnkctl);
280 	if (lnkctl & PCI_EXP_LNKCTL_RCB)
281 		return true;
282 
283 	return false;
284 }
285 
286 /* _HPX PCI Express Setting Record (Type 2) */
287 struct hpx_type2 {
288 	u32 revision;
289 	u32 unc_err_mask_and;
290 	u32 unc_err_mask_or;
291 	u32 unc_err_sever_and;
292 	u32 unc_err_sever_or;
293 	u32 cor_err_mask_and;
294 	u32 cor_err_mask_or;
295 	u32 adv_err_cap_and;
296 	u32 adv_err_cap_or;
297 	u16 pci_exp_devctl_and;
298 	u16 pci_exp_devctl_or;
299 	u16 pci_exp_lnkctl_and;
300 	u16 pci_exp_lnkctl_or;
301 	u32 sec_unc_err_sever_and;
302 	u32 sec_unc_err_sever_or;
303 	u32 sec_unc_err_mask_and;
304 	u32 sec_unc_err_mask_or;
305 };
306 
307 static void program_hpx_type2(struct pci_dev *dev, struct hpx_type2 *hpx)
308 {
309 	int pos;
310 	u32 reg32;
311 
312 	if (!hpx)
313 		return;
314 
315 	if (!pci_is_pcie(dev))
316 		return;
317 
318 	if (hpx->revision > 1) {
319 		pci_warn(dev, "PCIe settings rev %d not supported\n",
320 			 hpx->revision);
321 		return;
322 	}
323 
324 	/*
325 	 * Don't allow _HPX to change MPS or MRRS settings.  We manage
326 	 * those to make sure they're consistent with the rest of the
327 	 * platform.
328 	 */
329 	hpx->pci_exp_devctl_and |= PCI_EXP_DEVCTL_PAYLOAD |
330 				    PCI_EXP_DEVCTL_READRQ;
331 	hpx->pci_exp_devctl_or &= ~(PCI_EXP_DEVCTL_PAYLOAD |
332 				    PCI_EXP_DEVCTL_READRQ);
333 
334 	/* Initialize Device Control Register */
335 	pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
336 			~hpx->pci_exp_devctl_and, hpx->pci_exp_devctl_or);
337 
338 	/* Initialize Link Control Register */
339 	if (pcie_cap_has_lnkctl(dev)) {
340 
341 		/*
342 		 * If the Root Port supports Read Completion Boundary of
343 		 * 128, set RCB to 128.  Otherwise, clear it.
344 		 */
345 		hpx->pci_exp_lnkctl_and |= PCI_EXP_LNKCTL_RCB;
346 		hpx->pci_exp_lnkctl_or &= ~PCI_EXP_LNKCTL_RCB;
347 		if (pcie_root_rcb_set(dev))
348 			hpx->pci_exp_lnkctl_or |= PCI_EXP_LNKCTL_RCB;
349 
350 		pcie_capability_clear_and_set_word(dev, PCI_EXP_LNKCTL,
351 			~hpx->pci_exp_lnkctl_and, hpx->pci_exp_lnkctl_or);
352 	}
353 
354 	/* Find Advanced Error Reporting Enhanced Capability */
355 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
356 	if (!pos)
357 		return;
358 
359 	/* Initialize Uncorrectable Error Mask Register */
360 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, &reg32);
361 	reg32 = (reg32 & hpx->unc_err_mask_and) | hpx->unc_err_mask_or;
362 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, reg32);
363 
364 	/* Initialize Uncorrectable Error Severity Register */
365 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &reg32);
366 	reg32 = (reg32 & hpx->unc_err_sever_and) | hpx->unc_err_sever_or;
367 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, reg32);
368 
369 	/* Initialize Correctable Error Mask Register */
370 	pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, &reg32);
371 	reg32 = (reg32 & hpx->cor_err_mask_and) | hpx->cor_err_mask_or;
372 	pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg32);
373 
374 	/* Initialize Advanced Error Capabilities and Control Register */
375 	pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
376 	reg32 = (reg32 & hpx->adv_err_cap_and) | hpx->adv_err_cap_or;
377 
378 	/* Don't enable ECRC generation or checking if unsupported */
379 	if (!(reg32 & PCI_ERR_CAP_ECRC_GENC))
380 		reg32 &= ~PCI_ERR_CAP_ECRC_GENE;
381 	if (!(reg32 & PCI_ERR_CAP_ECRC_CHKC))
382 		reg32 &= ~PCI_ERR_CAP_ECRC_CHKE;
383 	pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
384 
385 	/*
386 	 * FIXME: The following two registers are not supported yet.
387 	 *
388 	 *   o Secondary Uncorrectable Error Severity Register
389 	 *   o Secondary Uncorrectable Error Mask Register
390 	 */
391 }
392 
393 static acpi_status decode_type2_hpx_record(union acpi_object *record,
394 					   struct hpx_type2 *hpx2)
395 {
396 	int i;
397 	union acpi_object *fields = record->package.elements;
398 	u32 revision = fields[1].integer.value;
399 
400 	switch (revision) {
401 	case 1:
402 		if (record->package.count != 18)
403 			return AE_ERROR;
404 		for (i = 2; i < 18; i++)
405 			if (fields[i].type != ACPI_TYPE_INTEGER)
406 				return AE_ERROR;
407 		hpx2->revision      = revision;
408 		hpx2->unc_err_mask_and      = fields[2].integer.value;
409 		hpx2->unc_err_mask_or       = fields[3].integer.value;
410 		hpx2->unc_err_sever_and     = fields[4].integer.value;
411 		hpx2->unc_err_sever_or      = fields[5].integer.value;
412 		hpx2->cor_err_mask_and      = fields[6].integer.value;
413 		hpx2->cor_err_mask_or       = fields[7].integer.value;
414 		hpx2->adv_err_cap_and       = fields[8].integer.value;
415 		hpx2->adv_err_cap_or        = fields[9].integer.value;
416 		hpx2->pci_exp_devctl_and    = fields[10].integer.value;
417 		hpx2->pci_exp_devctl_or     = fields[11].integer.value;
418 		hpx2->pci_exp_lnkctl_and    = fields[12].integer.value;
419 		hpx2->pci_exp_lnkctl_or     = fields[13].integer.value;
420 		hpx2->sec_unc_err_sever_and = fields[14].integer.value;
421 		hpx2->sec_unc_err_sever_or  = fields[15].integer.value;
422 		hpx2->sec_unc_err_mask_and  = fields[16].integer.value;
423 		hpx2->sec_unc_err_mask_or   = fields[17].integer.value;
424 		break;
425 	default:
426 		pr_warn("%s: Type 2 Revision %d record not supported\n",
427 		       __func__, revision);
428 		return AE_ERROR;
429 	}
430 	return AE_OK;
431 }
432 
433 /* _HPX PCI Express Setting Record (Type 3) */
434 struct hpx_type3 {
435 	u16 device_type;
436 	u16 function_type;
437 	u16 config_space_location;
438 	u16 pci_exp_cap_id;
439 	u16 pci_exp_cap_ver;
440 	u16 pci_exp_vendor_id;
441 	u16 dvsec_id;
442 	u16 dvsec_rev;
443 	u16 match_offset;
444 	u32 match_mask_and;
445 	u32 match_value;
446 	u16 reg_offset;
447 	u32 reg_mask_and;
448 	u32 reg_mask_or;
449 };
450 
451 enum hpx_type3_dev_type {
452 	HPX_TYPE_ENDPOINT	= BIT(0),
453 	HPX_TYPE_LEG_END	= BIT(1),
454 	HPX_TYPE_RC_END		= BIT(2),
455 	HPX_TYPE_RC_EC		= BIT(3),
456 	HPX_TYPE_ROOT_PORT	= BIT(4),
457 	HPX_TYPE_UPSTREAM	= BIT(5),
458 	HPX_TYPE_DOWNSTREAM	= BIT(6),
459 	HPX_TYPE_PCI_BRIDGE	= BIT(7),
460 	HPX_TYPE_PCIE_BRIDGE	= BIT(8),
461 };
462 
463 static u16 hpx3_device_type(struct pci_dev *dev)
464 {
465 	u16 pcie_type = pci_pcie_type(dev);
466 	static const int pcie_to_hpx3_type[] = {
467 		[PCI_EXP_TYPE_ENDPOINT]    = HPX_TYPE_ENDPOINT,
468 		[PCI_EXP_TYPE_LEG_END]     = HPX_TYPE_LEG_END,
469 		[PCI_EXP_TYPE_RC_END]      = HPX_TYPE_RC_END,
470 		[PCI_EXP_TYPE_RC_EC]       = HPX_TYPE_RC_EC,
471 		[PCI_EXP_TYPE_ROOT_PORT]   = HPX_TYPE_ROOT_PORT,
472 		[PCI_EXP_TYPE_UPSTREAM]    = HPX_TYPE_UPSTREAM,
473 		[PCI_EXP_TYPE_DOWNSTREAM]  = HPX_TYPE_DOWNSTREAM,
474 		[PCI_EXP_TYPE_PCI_BRIDGE]  = HPX_TYPE_PCI_BRIDGE,
475 		[PCI_EXP_TYPE_PCIE_BRIDGE] = HPX_TYPE_PCIE_BRIDGE,
476 	};
477 
478 	if (pcie_type >= ARRAY_SIZE(pcie_to_hpx3_type))
479 		return 0;
480 
481 	return pcie_to_hpx3_type[pcie_type];
482 }
483 
484 enum hpx_type3_fn_type {
485 	HPX_FN_NORMAL		= BIT(0),
486 	HPX_FN_SRIOV_PHYS	= BIT(1),
487 	HPX_FN_SRIOV_VIRT	= BIT(2),
488 };
489 
490 static u8 hpx3_function_type(struct pci_dev *dev)
491 {
492 	if (dev->is_virtfn)
493 		return HPX_FN_SRIOV_VIRT;
494 	else if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV) > 0)
495 		return HPX_FN_SRIOV_PHYS;
496 	else
497 		return HPX_FN_NORMAL;
498 }
499 
500 static bool hpx3_cap_ver_matches(u8 pcie_cap_id, u8 hpx3_cap_id)
501 {
502 	u8 cap_ver = hpx3_cap_id & 0xf;
503 
504 	if ((hpx3_cap_id & BIT(4)) && cap_ver >= pcie_cap_id)
505 		return true;
506 	else if (cap_ver == pcie_cap_id)
507 		return true;
508 
509 	return false;
510 }
511 
512 enum hpx_type3_cfg_loc {
513 	HPX_CFG_PCICFG		= 0,
514 	HPX_CFG_PCIE_CAP	= 1,
515 	HPX_CFG_PCIE_CAP_EXT	= 2,
516 	HPX_CFG_VEND_CAP	= 3,
517 	HPX_CFG_DVSEC		= 4,
518 	HPX_CFG_MAX,
519 };
520 
521 static void program_hpx_type3_register(struct pci_dev *dev,
522 				       const struct hpx_type3 *reg)
523 {
524 	u32 match_reg, write_reg, header, orig_value;
525 	u16 pos;
526 
527 	if (!(hpx3_device_type(dev) & reg->device_type))
528 		return;
529 
530 	if (!(hpx3_function_type(dev) & reg->function_type))
531 		return;
532 
533 	switch (reg->config_space_location) {
534 	case HPX_CFG_PCICFG:
535 		pos = 0;
536 		break;
537 	case HPX_CFG_PCIE_CAP:
538 		pos = pci_find_capability(dev, reg->pci_exp_cap_id);
539 		if (pos == 0)
540 			return;
541 
542 		break;
543 	case HPX_CFG_PCIE_CAP_EXT:
544 		pos = pci_find_ext_capability(dev, reg->pci_exp_cap_id);
545 		if (pos == 0)
546 			return;
547 
548 		pci_read_config_dword(dev, pos, &header);
549 		if (!hpx3_cap_ver_matches(PCI_EXT_CAP_VER(header),
550 					  reg->pci_exp_cap_ver))
551 			return;
552 
553 		break;
554 	case HPX_CFG_VEND_CAP:
555 	case HPX_CFG_DVSEC:
556 	default:
557 		pci_warn(dev, "Encountered _HPX type 3 with unsupported config space location");
558 		return;
559 	}
560 
561 	pci_read_config_dword(dev, pos + reg->match_offset, &match_reg);
562 
563 	if ((match_reg & reg->match_mask_and) != reg->match_value)
564 		return;
565 
566 	pci_read_config_dword(dev, pos + reg->reg_offset, &write_reg);
567 	orig_value = write_reg;
568 	write_reg &= reg->reg_mask_and;
569 	write_reg |= reg->reg_mask_or;
570 
571 	if (orig_value == write_reg)
572 		return;
573 
574 	pci_write_config_dword(dev, pos + reg->reg_offset, write_reg);
575 
576 	pci_dbg(dev, "Applied _HPX3 at [0x%x]: 0x%08x -> 0x%08x",
577 		pos, orig_value, write_reg);
578 }
579 
580 static void program_hpx_type3(struct pci_dev *dev, struct hpx_type3 *hpx)
581 {
582 	if (!hpx)
583 		return;
584 
585 	if (!pci_is_pcie(dev))
586 		return;
587 
588 	program_hpx_type3_register(dev, hpx);
589 }
590 
591 static void parse_hpx3_register(struct hpx_type3 *hpx3_reg,
592 				union acpi_object *reg_fields)
593 {
594 	hpx3_reg->device_type            = reg_fields[0].integer.value;
595 	hpx3_reg->function_type          = reg_fields[1].integer.value;
596 	hpx3_reg->config_space_location  = reg_fields[2].integer.value;
597 	hpx3_reg->pci_exp_cap_id         = reg_fields[3].integer.value;
598 	hpx3_reg->pci_exp_cap_ver        = reg_fields[4].integer.value;
599 	hpx3_reg->pci_exp_vendor_id      = reg_fields[5].integer.value;
600 	hpx3_reg->dvsec_id               = reg_fields[6].integer.value;
601 	hpx3_reg->dvsec_rev              = reg_fields[7].integer.value;
602 	hpx3_reg->match_offset           = reg_fields[8].integer.value;
603 	hpx3_reg->match_mask_and         = reg_fields[9].integer.value;
604 	hpx3_reg->match_value            = reg_fields[10].integer.value;
605 	hpx3_reg->reg_offset             = reg_fields[11].integer.value;
606 	hpx3_reg->reg_mask_and           = reg_fields[12].integer.value;
607 	hpx3_reg->reg_mask_or            = reg_fields[13].integer.value;
608 }
609 
610 static acpi_status program_type3_hpx_record(struct pci_dev *dev,
611 					   union acpi_object *record)
612 {
613 	union acpi_object *fields = record->package.elements;
614 	u32 desc_count, expected_length, revision;
615 	union acpi_object *reg_fields;
616 	struct hpx_type3 hpx3;
617 	int i;
618 
619 	revision = fields[1].integer.value;
620 	switch (revision) {
621 	case 1:
622 		desc_count = fields[2].integer.value;
623 		expected_length = 3 + desc_count * 14;
624 
625 		if (record->package.count != expected_length)
626 			return AE_ERROR;
627 
628 		for (i = 2; i < expected_length; i++)
629 			if (fields[i].type != ACPI_TYPE_INTEGER)
630 				return AE_ERROR;
631 
632 		for (i = 0; i < desc_count; i++) {
633 			reg_fields = fields + 3 + i * 14;
634 			parse_hpx3_register(&hpx3, reg_fields);
635 			program_hpx_type3(dev, &hpx3);
636 		}
637 
638 		break;
639 	default:
640 		printk(KERN_WARNING
641 			"%s: Type 3 Revision %d record not supported\n",
642 			__func__, revision);
643 		return AE_ERROR;
644 	}
645 	return AE_OK;
646 }
647 
648 static acpi_status acpi_run_hpx(struct pci_dev *dev, acpi_handle handle)
649 {
650 	acpi_status status;
651 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
652 	union acpi_object *package, *record, *fields;
653 	struct hpx_type0 hpx0;
654 	struct hpx_type1 hpx1;
655 	struct hpx_type2 hpx2;
656 	u32 type;
657 	int i;
658 
659 	status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
660 	if (ACPI_FAILURE(status))
661 		return status;
662 
663 	package = (union acpi_object *)buffer.pointer;
664 	if (package->type != ACPI_TYPE_PACKAGE) {
665 		status = AE_ERROR;
666 		goto exit;
667 	}
668 
669 	for (i = 0; i < package->package.count; i++) {
670 		record = &package->package.elements[i];
671 		if (record->type != ACPI_TYPE_PACKAGE) {
672 			status = AE_ERROR;
673 			goto exit;
674 		}
675 
676 		fields = record->package.elements;
677 		if (fields[0].type != ACPI_TYPE_INTEGER ||
678 		    fields[1].type != ACPI_TYPE_INTEGER) {
679 			status = AE_ERROR;
680 			goto exit;
681 		}
682 
683 		type = fields[0].integer.value;
684 		switch (type) {
685 		case 0:
686 			memset(&hpx0, 0, sizeof(hpx0));
687 			status = decode_type0_hpx_record(record, &hpx0);
688 			if (ACPI_FAILURE(status))
689 				goto exit;
690 			program_hpx_type0(dev, &hpx0);
691 			break;
692 		case 1:
693 			memset(&hpx1, 0, sizeof(hpx1));
694 			status = decode_type1_hpx_record(record, &hpx1);
695 			if (ACPI_FAILURE(status))
696 				goto exit;
697 			program_hpx_type1(dev, &hpx1);
698 			break;
699 		case 2:
700 			memset(&hpx2, 0, sizeof(hpx2));
701 			status = decode_type2_hpx_record(record, &hpx2);
702 			if (ACPI_FAILURE(status))
703 				goto exit;
704 			program_hpx_type2(dev, &hpx2);
705 			break;
706 		case 3:
707 			status = program_type3_hpx_record(dev, record);
708 			if (ACPI_FAILURE(status))
709 				goto exit;
710 			break;
711 		default:
712 			pr_err("%s: Type %d record not supported\n",
713 			       __func__, type);
714 			status = AE_ERROR;
715 			goto exit;
716 		}
717 	}
718  exit:
719 	kfree(buffer.pointer);
720 	return status;
721 }
722 
723 static acpi_status acpi_run_hpp(struct pci_dev *dev, acpi_handle handle)
724 {
725 	acpi_status status;
726 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
727 	union acpi_object *package, *fields;
728 	struct hpx_type0 hpx0;
729 	int i;
730 
731 	memset(&hpx0, 0, sizeof(hpx0));
732 
733 	status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer);
734 	if (ACPI_FAILURE(status))
735 		return status;
736 
737 	package = (union acpi_object *) buffer.pointer;
738 	if (package->type != ACPI_TYPE_PACKAGE ||
739 	    package->package.count != 4) {
740 		status = AE_ERROR;
741 		goto exit;
742 	}
743 
744 	fields = package->package.elements;
745 	for (i = 0; i < 4; i++) {
746 		if (fields[i].type != ACPI_TYPE_INTEGER) {
747 			status = AE_ERROR;
748 			goto exit;
749 		}
750 	}
751 
752 	hpx0.revision        = 1;
753 	hpx0.cache_line_size = fields[0].integer.value;
754 	hpx0.latency_timer   = fields[1].integer.value;
755 	hpx0.enable_serr     = fields[2].integer.value;
756 	hpx0.enable_perr     = fields[3].integer.value;
757 
758 	program_hpx_type0(dev, &hpx0);
759 
760 exit:
761 	kfree(buffer.pointer);
762 	return status;
763 }
764 
765 /* pci_acpi_program_hp_params
766  *
767  * @dev - the pci_dev for which we want parameters
768  */
769 int pci_acpi_program_hp_params(struct pci_dev *dev)
770 {
771 	acpi_status status;
772 	acpi_handle handle, phandle;
773 	struct pci_bus *pbus;
774 
775 	if (acpi_pci_disabled)
776 		return -ENODEV;
777 
778 	handle = NULL;
779 	for (pbus = dev->bus; pbus; pbus = pbus->parent) {
780 		handle = acpi_pci_get_bridge_handle(pbus);
781 		if (handle)
782 			break;
783 	}
784 
785 	/*
786 	 * _HPP settings apply to all child buses, until another _HPP is
787 	 * encountered. If we don't find an _HPP for the input pci dev,
788 	 * look for it in the parent device scope since that would apply to
789 	 * this pci dev.
790 	 */
791 	while (handle) {
792 		status = acpi_run_hpx(dev, handle);
793 		if (ACPI_SUCCESS(status))
794 			return 0;
795 		status = acpi_run_hpp(dev, handle);
796 		if (ACPI_SUCCESS(status))
797 			return 0;
798 		if (acpi_is_root_bridge(handle))
799 			break;
800 		status = acpi_get_parent(handle, &phandle);
801 		if (ACPI_FAILURE(status))
802 			break;
803 		handle = phandle;
804 	}
805 	return -ENODEV;
806 }
807 
808 /**
809  * pciehp_is_native - Check whether a hotplug port is handled by the OS
810  * @bridge: Hotplug port to check
811  *
812  * Returns true if the given @bridge is handled by the native PCIe hotplug
813  * driver.
814  */
815 bool pciehp_is_native(struct pci_dev *bridge)
816 {
817 	const struct pci_host_bridge *host;
818 	u32 slot_cap;
819 
820 	if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
821 		return false;
822 
823 	pcie_capability_read_dword(bridge, PCI_EXP_SLTCAP, &slot_cap);
824 	if (!(slot_cap & PCI_EXP_SLTCAP_HPC))
825 		return false;
826 
827 	if (pcie_ports_native)
828 		return true;
829 
830 	host = pci_find_host_bridge(bridge->bus);
831 	return host->native_pcie_hotplug;
832 }
833 
834 /**
835  * shpchp_is_native - Check whether a hotplug port is handled by the OS
836  * @bridge: Hotplug port to check
837  *
838  * Returns true if the given @bridge is handled by the native SHPC hotplug
839  * driver.
840  */
841 bool shpchp_is_native(struct pci_dev *bridge)
842 {
843 	return bridge->shpc_managed;
844 }
845 
846 /**
847  * pci_acpi_wake_bus - Root bus wakeup notification fork function.
848  * @context: Device wakeup context.
849  */
850 static void pci_acpi_wake_bus(struct acpi_device_wakeup_context *context)
851 {
852 	struct acpi_device *adev;
853 	struct acpi_pci_root *root;
854 
855 	adev = container_of(context, struct acpi_device, wakeup.context);
856 	root = acpi_driver_data(adev);
857 	pci_pme_wakeup_bus(root->bus);
858 }
859 
860 /**
861  * pci_acpi_wake_dev - PCI device wakeup notification work function.
862  * @context: Device wakeup context.
863  */
864 static void pci_acpi_wake_dev(struct acpi_device_wakeup_context *context)
865 {
866 	struct pci_dev *pci_dev;
867 
868 	pci_dev = to_pci_dev(context->dev);
869 
870 	if (pci_dev->pme_poll)
871 		pci_dev->pme_poll = false;
872 
873 	if (pci_dev->current_state == PCI_D3cold) {
874 		pci_wakeup_event(pci_dev);
875 		pm_request_resume(&pci_dev->dev);
876 		return;
877 	}
878 
879 	/* Clear PME Status if set. */
880 	if (pci_dev->pme_support)
881 		pci_check_pme_status(pci_dev);
882 
883 	pci_wakeup_event(pci_dev);
884 	pm_request_resume(&pci_dev->dev);
885 
886 	pci_pme_wakeup_bus(pci_dev->subordinate);
887 }
888 
889 /**
890  * pci_acpi_add_bus_pm_notifier - Register PM notifier for root PCI bus.
891  * @dev: PCI root bridge ACPI device.
892  */
893 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev)
894 {
895 	return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus);
896 }
897 
898 /**
899  * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
900  * @dev: ACPI device to add the notifier for.
901  * @pci_dev: PCI device to check for the PME status if an event is signaled.
902  */
903 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
904 				     struct pci_dev *pci_dev)
905 {
906 	return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev);
907 }
908 
909 /*
910  * _SxD returns the D-state with the highest power
911  * (lowest D-state number) supported in the S-state "x".
912  *
913  * If the devices does not have a _PRW
914  * (Power Resources for Wake) supporting system wakeup from "x"
915  * then the OS is free to choose a lower power (higher number
916  * D-state) than the return value from _SxD.
917  *
918  * But if _PRW is enabled at S-state "x", the OS
919  * must not choose a power lower than _SxD --
920  * unless the device has an _SxW method specifying
921  * the lowest power (highest D-state number) the device
922  * may enter while still able to wake the system.
923  *
924  * ie. depending on global OS policy:
925  *
926  * if (_PRW at S-state x)
927  *	choose from highest power _SxD to lowest power _SxW
928  * else // no _PRW at S-state x
929  *	choose highest power _SxD or any lower power
930  */
931 
932 pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
933 {
934 	int acpi_state, d_max;
935 
936 	if (pdev->no_d3cold || !pdev->d3cold_allowed)
937 		d_max = ACPI_STATE_D3_HOT;
938 	else
939 		d_max = ACPI_STATE_D3_COLD;
940 	acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max);
941 	if (acpi_state < 0)
942 		return PCI_POWER_ERROR;
943 
944 	switch (acpi_state) {
945 	case ACPI_STATE_D0:
946 		return PCI_D0;
947 	case ACPI_STATE_D1:
948 		return PCI_D1;
949 	case ACPI_STATE_D2:
950 		return PCI_D2;
951 	case ACPI_STATE_D3_HOT:
952 		return PCI_D3hot;
953 	case ACPI_STATE_D3_COLD:
954 		return PCI_D3cold;
955 	}
956 	return PCI_POWER_ERROR;
957 }
958 
959 static struct acpi_device *acpi_pci_find_companion(struct device *dev);
960 
961 void pci_set_acpi_fwnode(struct pci_dev *dev)
962 {
963 	if (!dev_fwnode(&dev->dev) && !pci_dev_is_added(dev))
964 		ACPI_COMPANION_SET(&dev->dev,
965 				   acpi_pci_find_companion(&dev->dev));
966 }
967 
968 /**
969  * pci_dev_acpi_reset - do a function level reset using _RST method
970  * @dev: device to reset
971  * @probe: if true, return 0 if device supports _RST
972  */
973 int pci_dev_acpi_reset(struct pci_dev *dev, bool probe)
974 {
975 	acpi_handle handle = ACPI_HANDLE(&dev->dev);
976 
977 	if (!handle || !acpi_has_method(handle, "_RST"))
978 		return -ENOTTY;
979 
980 	if (probe)
981 		return 0;
982 
983 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_RST", NULL, NULL))) {
984 		pci_warn(dev, "ACPI _RST failed\n");
985 		return -ENOTTY;
986 	}
987 
988 	return 0;
989 }
990 
991 bool acpi_pci_power_manageable(struct pci_dev *dev)
992 {
993 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
994 
995 	return adev && acpi_device_power_manageable(adev);
996 }
997 
998 bool acpi_pci_bridge_d3(struct pci_dev *dev)
999 {
1000 	struct pci_dev *rpdev;
1001 	struct acpi_device *adev, *rpadev;
1002 	const union acpi_object *obj;
1003 
1004 	if (acpi_pci_disabled || !dev->is_hotplug_bridge)
1005 		return false;
1006 
1007 	adev = ACPI_COMPANION(&dev->dev);
1008 	if (adev) {
1009 		/*
1010 		 * If the bridge has _S0W, whether or not it can go into D3
1011 		 * depends on what is returned by that object.  In particular,
1012 		 * if the power state returned by _S0W is D2 or shallower,
1013 		 * entering D3 should not be allowed.
1014 		 */
1015 		if (acpi_dev_power_state_for_wake(adev) <= ACPI_STATE_D2)
1016 			return false;
1017 
1018 		/*
1019 		 * Otherwise, assume that the bridge can enter D3 so long as it
1020 		 * is power-manageable via ACPI.
1021 		 */
1022 		if (acpi_device_power_manageable(adev))
1023 			return true;
1024 	}
1025 
1026 	rpdev = pcie_find_root_port(dev);
1027 	if (!rpdev)
1028 		return false;
1029 
1030 	if (rpdev == dev)
1031 		rpadev = adev;
1032 	else
1033 		rpadev = ACPI_COMPANION(&rpdev->dev);
1034 
1035 	if (!rpadev)
1036 		return false;
1037 
1038 	/*
1039 	 * If the Root Port cannot signal wakeup signals at all, i.e., it
1040 	 * doesn't supply a wakeup GPE via _PRW, it cannot signal hotplug
1041 	 * events from low-power states including D3hot and D3cold.
1042 	 */
1043 	if (!rpadev->wakeup.flags.valid)
1044 		return false;
1045 
1046 	/*
1047 	 * In the bridge-below-a-Root-Port case, evaluate _S0W for the Root Port
1048 	 * to verify whether or not it can signal wakeup from D3.
1049 	 */
1050 	if (rpadev != adev &&
1051 	    acpi_dev_power_state_for_wake(rpadev) <= ACPI_STATE_D2)
1052 		return false;
1053 
1054 	/*
1055 	 * The "HotPlugSupportInD3" property in a Root Port _DSD indicates
1056 	 * the Port can signal hotplug events while in D3.  We assume any
1057 	 * bridges *below* that Root Port can also signal hotplug events
1058 	 * while in D3.
1059 	 */
1060 	if (!acpi_dev_get_property(rpadev, "HotPlugSupportInD3",
1061 				   ACPI_TYPE_INTEGER, &obj) &&
1062 	    obj->integer.value == 1)
1063 		return true;
1064 
1065 	return false;
1066 }
1067 
1068 static void acpi_pci_config_space_access(struct pci_dev *dev, bool enable)
1069 {
1070 	int val = enable ? ACPI_REG_CONNECT : ACPI_REG_DISCONNECT;
1071 	int ret = acpi_evaluate_reg(ACPI_HANDLE(&dev->dev),
1072 				    ACPI_ADR_SPACE_PCI_CONFIG, val);
1073 	if (ret)
1074 		pci_dbg(dev, "ACPI _REG %s evaluation failed (%d)\n",
1075 			enable ? "connect" : "disconnect", ret);
1076 }
1077 
1078 int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
1079 {
1080 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
1081 	static const u8 state_conv[] = {
1082 		[PCI_D0] = ACPI_STATE_D0,
1083 		[PCI_D1] = ACPI_STATE_D1,
1084 		[PCI_D2] = ACPI_STATE_D2,
1085 		[PCI_D3hot] = ACPI_STATE_D3_HOT,
1086 		[PCI_D3cold] = ACPI_STATE_D3_COLD,
1087 	};
1088 	int error;
1089 
1090 	/* If the ACPI device has _EJ0, ignore the device */
1091 	if (!adev || acpi_has_method(adev->handle, "_EJ0"))
1092 		return -ENODEV;
1093 
1094 	switch (state) {
1095 	case PCI_D0:
1096 	case PCI_D1:
1097 	case PCI_D2:
1098 	case PCI_D3hot:
1099 	case PCI_D3cold:
1100 		break;
1101 	default:
1102 		return -EINVAL;
1103 	}
1104 
1105 	if (state == PCI_D3cold) {
1106 		if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) ==
1107 				PM_QOS_FLAGS_ALL)
1108 			return -EBUSY;
1109 
1110 		/* Notify AML lack of PCI config space availability */
1111 		acpi_pci_config_space_access(dev, false);
1112 	}
1113 
1114 	error = acpi_device_set_power(adev, state_conv[state]);
1115 	if (error)
1116 		return error;
1117 
1118 	pci_dbg(dev, "power state changed by ACPI to %s\n",
1119 	        acpi_power_state_string(adev->power.state));
1120 
1121 	/*
1122 	 * Notify AML of PCI config space availability.  Config space is
1123 	 * accessible in all states except D3cold; the only transitions
1124 	 * that change availability are transitions to D3cold and from
1125 	 * D3cold to D0.
1126 	 */
1127 	if (state == PCI_D0)
1128 		acpi_pci_config_space_access(dev, true);
1129 
1130 	return 0;
1131 }
1132 
1133 pci_power_t acpi_pci_get_power_state(struct pci_dev *dev)
1134 {
1135 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
1136 	static const pci_power_t state_conv[] = {
1137 		[ACPI_STATE_D0]      = PCI_D0,
1138 		[ACPI_STATE_D1]      = PCI_D1,
1139 		[ACPI_STATE_D2]      = PCI_D2,
1140 		[ACPI_STATE_D3_HOT]  = PCI_D3hot,
1141 		[ACPI_STATE_D3_COLD] = PCI_D3cold,
1142 	};
1143 	int state;
1144 
1145 	if (!adev || !acpi_device_power_manageable(adev))
1146 		return PCI_UNKNOWN;
1147 
1148 	state = adev->power.state;
1149 	if (state == ACPI_STATE_UNKNOWN)
1150 		return PCI_UNKNOWN;
1151 
1152 	return state_conv[state];
1153 }
1154 
1155 void acpi_pci_refresh_power_state(struct pci_dev *dev)
1156 {
1157 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
1158 
1159 	if (adev && acpi_device_power_manageable(adev))
1160 		acpi_device_update_power(adev, NULL);
1161 }
1162 
1163 static int acpi_pci_propagate_wakeup(struct pci_bus *bus, bool enable)
1164 {
1165 	while (bus->parent) {
1166 		if (acpi_pm_device_can_wakeup(&bus->self->dev))
1167 			return acpi_pm_set_device_wakeup(&bus->self->dev, enable);
1168 
1169 		bus = bus->parent;
1170 	}
1171 
1172 	/* We have reached the root bus. */
1173 	if (bus->bridge) {
1174 		if (acpi_pm_device_can_wakeup(bus->bridge))
1175 			return acpi_pm_set_device_wakeup(bus->bridge, enable);
1176 	}
1177 	return 0;
1178 }
1179 
1180 int acpi_pci_wakeup(struct pci_dev *dev, bool enable)
1181 {
1182 	if (acpi_pci_disabled)
1183 		return 0;
1184 
1185 	if (acpi_pm_device_can_wakeup(&dev->dev))
1186 		return acpi_pm_set_device_wakeup(&dev->dev, enable);
1187 
1188 	return acpi_pci_propagate_wakeup(dev->bus, enable);
1189 }
1190 
1191 bool acpi_pci_need_resume(struct pci_dev *dev)
1192 {
1193 	struct acpi_device *adev;
1194 
1195 	if (acpi_pci_disabled)
1196 		return false;
1197 
1198 	/*
1199 	 * In some cases (eg. Samsung 305V4A) leaving a bridge in suspend over
1200 	 * system-wide suspend/resume confuses the platform firmware, so avoid
1201 	 * doing that.  According to Section 16.1.6 of ACPI 6.2, endpoint
1202 	 * devices are expected to be in D3 before invoking the S3 entry path
1203 	 * from the firmware, so they should not be affected by this issue.
1204 	 */
1205 	if (pci_is_bridge(dev) && acpi_target_system_state() != ACPI_STATE_S0)
1206 		return true;
1207 
1208 	adev = ACPI_COMPANION(&dev->dev);
1209 	if (!adev || !acpi_device_power_manageable(adev))
1210 		return false;
1211 
1212 	if (adev->wakeup.flags.valid &&
1213 	    device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count)
1214 		return true;
1215 
1216 	if (acpi_target_system_state() == ACPI_STATE_S0)
1217 		return false;
1218 
1219 	return !!adev->power.flags.dsw_present;
1220 }
1221 
1222 void acpi_pci_add_bus(struct pci_bus *bus)
1223 {
1224 	union acpi_object *obj;
1225 	struct pci_host_bridge *bridge;
1226 
1227 	if (acpi_pci_disabled || !bus->bridge || !ACPI_HANDLE(bus->bridge))
1228 		return;
1229 
1230 	acpi_pci_slot_enumerate(bus);
1231 	acpiphp_enumerate_slots(bus);
1232 
1233 	/*
1234 	 * For a host bridge, check its _DSM for function 8 and if
1235 	 * that is available, mark it in pci_host_bridge.
1236 	 */
1237 	if (!pci_is_root_bus(bus))
1238 		return;
1239 
1240 	obj = acpi_evaluate_dsm_typed(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 3,
1241 				      DSM_PCI_POWER_ON_RESET_DELAY, NULL, ACPI_TYPE_INTEGER);
1242 	if (!obj)
1243 		return;
1244 
1245 	if (obj->integer.value == 1) {
1246 		bridge = pci_find_host_bridge(bus);
1247 		bridge->ignore_reset_delay = 1;
1248 	}
1249 	ACPI_FREE(obj);
1250 }
1251 
1252 void acpi_pci_remove_bus(struct pci_bus *bus)
1253 {
1254 	if (acpi_pci_disabled || !bus->bridge)
1255 		return;
1256 
1257 	acpiphp_remove_slots(bus);
1258 	acpi_pci_slot_remove(bus);
1259 }
1260 
1261 /* ACPI bus type */
1262 
1263 
1264 static DECLARE_RWSEM(pci_acpi_companion_lookup_sem);
1265 static struct acpi_device *(*pci_acpi_find_companion_hook)(struct pci_dev *);
1266 
1267 /**
1268  * pci_acpi_set_companion_lookup_hook - Set ACPI companion lookup callback.
1269  * @func: ACPI companion lookup callback pointer or NULL.
1270  *
1271  * Set a special ACPI companion lookup callback for PCI devices whose companion
1272  * objects in the ACPI namespace have _ADR with non-standard bus-device-function
1273  * encodings.
1274  *
1275  * Return 0 on success or a negative error code on failure (in which case no
1276  * changes are made).
1277  *
1278  * The caller is responsible for the appropriate ordering of the invocations of
1279  * this function with respect to the enumeration of the PCI devices needing the
1280  * callback installed by it.
1281  */
1282 int pci_acpi_set_companion_lookup_hook(struct acpi_device *(*func)(struct pci_dev *))
1283 {
1284 	int ret;
1285 
1286 	if (!func)
1287 		return -EINVAL;
1288 
1289 	down_write(&pci_acpi_companion_lookup_sem);
1290 
1291 	if (pci_acpi_find_companion_hook) {
1292 		ret = -EBUSY;
1293 	} else {
1294 		pci_acpi_find_companion_hook = func;
1295 		ret = 0;
1296 	}
1297 
1298 	up_write(&pci_acpi_companion_lookup_sem);
1299 
1300 	return ret;
1301 }
1302 EXPORT_SYMBOL_GPL(pci_acpi_set_companion_lookup_hook);
1303 
1304 /**
1305  * pci_acpi_clear_companion_lookup_hook - Clear ACPI companion lookup callback.
1306  *
1307  * Clear the special ACPI companion lookup callback previously set by
1308  * pci_acpi_set_companion_lookup_hook().  Block until the last running instance
1309  * of the callback returns before clearing it.
1310  *
1311  * The caller is responsible for the appropriate ordering of the invocations of
1312  * this function with respect to the enumeration of the PCI devices needing the
1313  * callback cleared by it.
1314  */
1315 void pci_acpi_clear_companion_lookup_hook(void)
1316 {
1317 	down_write(&pci_acpi_companion_lookup_sem);
1318 
1319 	pci_acpi_find_companion_hook = NULL;
1320 
1321 	up_write(&pci_acpi_companion_lookup_sem);
1322 }
1323 EXPORT_SYMBOL_GPL(pci_acpi_clear_companion_lookup_hook);
1324 
1325 static struct acpi_device *acpi_pci_find_companion(struct device *dev)
1326 {
1327 	struct pci_dev *pci_dev = to_pci_dev(dev);
1328 	struct acpi_device *adev;
1329 	bool check_children;
1330 	u64 addr;
1331 
1332 	if (!dev->parent)
1333 		return NULL;
1334 
1335 	down_read(&pci_acpi_companion_lookup_sem);
1336 
1337 	adev = pci_acpi_find_companion_hook ?
1338 		pci_acpi_find_companion_hook(pci_dev) : NULL;
1339 
1340 	up_read(&pci_acpi_companion_lookup_sem);
1341 
1342 	if (adev)
1343 		return adev;
1344 
1345 	check_children = pci_is_bridge(pci_dev);
1346 	/* Please ref to ACPI spec for the syntax of _ADR */
1347 	addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
1348 	adev = acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
1349 				      check_children);
1350 
1351 	/*
1352 	 * There may be ACPI device objects in the ACPI namespace that are
1353 	 * children of the device object representing the host bridge, but don't
1354 	 * represent PCI devices.  Both _HID and _ADR may be present for them,
1355 	 * even though that is against the specification (for example, see
1356 	 * Section 6.1 of ACPI 6.3), but in many cases the _ADR returns 0 which
1357 	 * appears to indicate that they should not be taken into consideration
1358 	 * as potential companions of PCI devices on the root bus.
1359 	 *
1360 	 * To catch this special case, disregard the returned device object if
1361 	 * it has a valid _HID, addr is 0 and the PCI device at hand is on the
1362 	 * root bus.
1363 	 */
1364 	if (adev && adev->pnp.type.platform_id && !addr &&
1365 	    pci_is_root_bus(pci_dev->bus))
1366 		return NULL;
1367 
1368 	return adev;
1369 }
1370 
1371 /**
1372  * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
1373  * @pdev: the PCI device whose delay is to be updated
1374  * @handle: ACPI handle of this device
1375  *
1376  * Update the d3hot_delay and d3cold_delay of a PCI device from the ACPI _DSM
1377  * control method of either the device itself or the PCI host bridge.
1378  *
1379  * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
1380  * host bridge.  If it returns one, the OS may assume that all devices in
1381  * the hierarchy have already completed power-on reset delays.
1382  *
1383  * Function 9, "Device Readiness Durations," applies only to the object
1384  * where it is located.  It returns delay durations required after various
1385  * events if the device requires less time than the spec requires.  Delays
1386  * from this function take precedence over the Reset Delay function.
1387  *
1388  * These _DSM functions are defined by the draft ECN of January 28, 2014,
1389  * titled "ACPI additions for FW latency optimizations."
1390  */
1391 static void pci_acpi_optimize_delay(struct pci_dev *pdev,
1392 				    acpi_handle handle)
1393 {
1394 	struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
1395 	int value;
1396 	union acpi_object *obj, *elements;
1397 
1398 	if (bridge->ignore_reset_delay)
1399 		pdev->d3cold_delay = 0;
1400 
1401 	obj = acpi_evaluate_dsm_typed(handle, &pci_acpi_dsm_guid, 3,
1402 				      DSM_PCI_DEVICE_READINESS_DURATIONS, NULL,
1403 				      ACPI_TYPE_PACKAGE);
1404 	if (!obj)
1405 		return;
1406 
1407 	if (obj->package.count == 5) {
1408 		elements = obj->package.elements;
1409 		if (elements[0].type == ACPI_TYPE_INTEGER) {
1410 			value = (int)elements[0].integer.value / 1000;
1411 			if (value < PCI_PM_D3COLD_WAIT)
1412 				pdev->d3cold_delay = value;
1413 		}
1414 		if (elements[3].type == ACPI_TYPE_INTEGER) {
1415 			value = (int)elements[3].integer.value / 1000;
1416 			if (value < PCI_PM_D3HOT_WAIT)
1417 				pdev->d3hot_delay = value;
1418 		}
1419 	}
1420 	ACPI_FREE(obj);
1421 }
1422 
1423 static void pci_acpi_set_external_facing(struct pci_dev *dev)
1424 {
1425 	u8 val;
1426 
1427 	if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
1428 		return;
1429 	if (device_property_read_u8(&dev->dev, "ExternalFacingPort", &val))
1430 		return;
1431 
1432 	/*
1433 	 * These root ports expose PCIe (including DMA) outside of the
1434 	 * system.  Everything downstream from them is external.
1435 	 */
1436 	if (val)
1437 		dev->external_facing = 1;
1438 }
1439 
1440 void pci_acpi_setup(struct device *dev, struct acpi_device *adev)
1441 {
1442 	struct pci_dev *pci_dev = to_pci_dev(dev);
1443 
1444 	pci_acpi_optimize_delay(pci_dev, adev->handle);
1445 	pci_acpi_set_external_facing(pci_dev);
1446 	pci_acpi_add_edr_notifier(pci_dev);
1447 
1448 	pci_acpi_add_pm_notifier(adev, pci_dev);
1449 	if (!adev->wakeup.flags.valid)
1450 		return;
1451 
1452 	device_set_wakeup_capable(dev, true);
1453 	/*
1454 	 * For bridges that can do D3 we enable wake automatically (as
1455 	 * we do for the power management itself in that case). The
1456 	 * reason is that the bridge may have additional methods such as
1457 	 * _DSW that need to be called.
1458 	 */
1459 	if (pci_dev->bridge_d3)
1460 		device_wakeup_enable(dev);
1461 
1462 	acpi_pci_wakeup(pci_dev, false);
1463 	acpi_device_power_add_dependent(adev, dev);
1464 
1465 	if (pci_is_bridge(pci_dev))
1466 		acpi_dev_power_up_children_with_adr(adev);
1467 }
1468 
1469 void pci_acpi_cleanup(struct device *dev, struct acpi_device *adev)
1470 {
1471 	struct pci_dev *pci_dev = to_pci_dev(dev);
1472 
1473 	pci_acpi_remove_edr_notifier(pci_dev);
1474 	pci_acpi_remove_pm_notifier(adev);
1475 	if (adev->wakeup.flags.valid) {
1476 		acpi_device_power_remove_dependent(adev, dev);
1477 		if (pci_dev->bridge_d3)
1478 			device_wakeup_disable(dev);
1479 
1480 		device_set_wakeup_capable(dev, false);
1481 	}
1482 }
1483 
1484 static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev);
1485 
1486 /**
1487  * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode
1488  * @fn:       Callback matching a device to a fwnode that identifies a PCI
1489  *            MSI domain.
1490  *
1491  * This should be called by irqchip driver, which is the parent of
1492  * the MSI domain to provide callback interface to query fwnode.
1493  */
1494 void
1495 pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *))
1496 {
1497 	pci_msi_get_fwnode_cb = fn;
1498 }
1499 
1500 /**
1501  * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge
1502  * @bus:      The PCI host bridge bus.
1503  *
1504  * This function uses the callback function registered by
1505  * pci_msi_register_fwnode_provider() to retrieve the irq_domain with
1506  * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus.
1507  * This returns NULL on error or when the domain is not found.
1508  */
1509 struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus)
1510 {
1511 	struct fwnode_handle *fwnode;
1512 
1513 	if (!pci_msi_get_fwnode_cb)
1514 		return NULL;
1515 
1516 	fwnode = pci_msi_get_fwnode_cb(&bus->dev);
1517 	if (!fwnode)
1518 		return NULL;
1519 
1520 	return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
1521 }
1522 
1523 static int __init acpi_pci_init(void)
1524 {
1525 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
1526 		pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n");
1527 		pci_no_msi();
1528 	}
1529 
1530 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
1531 		pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
1532 		pcie_no_aspm();
1533 	}
1534 
1535 	if (acpi_pci_disabled)
1536 		return 0;
1537 
1538 	acpi_pci_slot_init();
1539 	acpiphp_init();
1540 
1541 	return 0;
1542 }
1543 arch_initcall(acpi_pci_init);
1544