xref: /linux/drivers/pci/pci-acpi.c (revision cb787f4ac0c2e439ea8d7e6387b925f74576bdf8)
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/pci-ecam.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/pm_qos.h>
21 #include <linux/rwsem.h>
22 #include "pci.h"
23 
24 /*
25  * The GUID is defined in the PCI Firmware Specification available
26  * here to PCI-SIG members:
27  * https://members.pcisig.com/wg/PCI-SIG/document/15350
28  */
29 const guid_t pci_acpi_dsm_guid =
30 	GUID_INIT(0xe5c937d0, 0x3553, 0x4d7a,
31 		  0x91, 0x17, 0xea, 0x4d, 0x19, 0xc3, 0x43, 0x4d);
32 
33 #if defined(CONFIG_PCI_QUIRKS) && defined(CONFIG_ARM64)
34 static int acpi_get_rc_addr(struct acpi_device *adev, struct resource *res)
35 {
36 	struct device *dev = &adev->dev;
37 	struct resource_entry *entry;
38 	struct list_head list;
39 	unsigned long flags;
40 	int ret;
41 
42 	INIT_LIST_HEAD(&list);
43 	flags = IORESOURCE_MEM;
44 	ret = acpi_dev_get_resources(adev, &list,
45 				     acpi_dev_filter_resource_type_cb,
46 				     (void *) flags);
47 	if (ret < 0) {
48 		dev_err(dev, "failed to parse _CRS method, error code %d\n",
49 			ret);
50 		return ret;
51 	}
52 
53 	if (ret == 0) {
54 		dev_err(dev, "no IO and memory resources present in _CRS\n");
55 		return -EINVAL;
56 	}
57 
58 	entry = list_first_entry(&list, struct resource_entry, node);
59 	*res = *entry->res;
60 	acpi_dev_free_resource_list(&list);
61 	return 0;
62 }
63 
64 static acpi_status acpi_match_rc(acpi_handle handle, u32 lvl, void *context,
65 				 void **retval)
66 {
67 	u16 *segment = context;
68 	unsigned long long uid;
69 	acpi_status status;
70 
71 	status = acpi_evaluate_integer(handle, METHOD_NAME__UID, NULL, &uid);
72 	if (ACPI_FAILURE(status) || uid != *segment)
73 		return AE_CTRL_DEPTH;
74 
75 	*(acpi_handle *)retval = handle;
76 	return AE_CTRL_TERMINATE;
77 }
78 
79 int acpi_get_rc_resources(struct device *dev, const char *hid, u16 segment,
80 			  struct resource *res)
81 {
82 	struct acpi_device *adev;
83 	acpi_status status;
84 	acpi_handle handle;
85 	int ret;
86 
87 	status = acpi_get_devices(hid, acpi_match_rc, &segment, &handle);
88 	if (ACPI_FAILURE(status)) {
89 		dev_err(dev, "can't find _HID %s device to locate resources\n",
90 			hid);
91 		return -ENODEV;
92 	}
93 
94 	adev = acpi_fetch_acpi_dev(handle);
95 	if (!adev)
96 		return -ENODEV;
97 
98 	ret = acpi_get_rc_addr(adev, res);
99 	if (ret) {
100 		dev_err(dev, "can't get resource from %s\n",
101 			dev_name(&adev->dev));
102 		return ret;
103 	}
104 
105 	return 0;
106 }
107 #endif
108 
109 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
110 {
111 	acpi_status status = AE_NOT_EXIST;
112 	unsigned long long mcfg_addr;
113 
114 	if (handle)
115 		status = acpi_evaluate_integer(handle, METHOD_NAME__CBA,
116 					       NULL, &mcfg_addr);
117 	if (ACPI_FAILURE(status))
118 		return 0;
119 
120 	return (phys_addr_t)mcfg_addr;
121 }
122 
123 bool pci_acpi_preserve_config(struct pci_host_bridge *host_bridge)
124 {
125 	if (ACPI_HANDLE(&host_bridge->dev)) {
126 		union acpi_object *obj;
127 
128 		/*
129 		 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
130 		 * exists and returns 0, we must preserve any PCI resource
131 		 * assignments made by firmware for this host bridge.
132 		 */
133 		obj = acpi_evaluate_dsm_typed(ACPI_HANDLE(&host_bridge->dev),
134 					      &pci_acpi_dsm_guid,
135 					      1, DSM_PCI_PRESERVE_BOOT_CONFIG,
136 					      NULL, ACPI_TYPE_INTEGER);
137 		if (obj && obj->integer.value == 0)
138 			return true;
139 		ACPI_FREE(obj);
140 	}
141 
142 	return false;
143 }
144 
145 /* _HPX PCI Setting Record (Type 0); same as _HPP */
146 struct hpx_type0 {
147 	u32 revision;		/* Not present in _HPP */
148 	u8  cache_line_size;	/* Not applicable to PCIe */
149 	u8  latency_timer;	/* Not applicable to PCIe */
150 	u8  enable_serr;
151 	u8  enable_perr;
152 };
153 
154 static struct hpx_type0 pci_default_type0 = {
155 	.revision = 1,
156 	.cache_line_size = 8,
157 	.latency_timer = 0x40,
158 	.enable_serr = 0,
159 	.enable_perr = 0,
160 };
161 
162 static void program_hpx_type0(struct pci_dev *dev, struct hpx_type0 *hpx)
163 {
164 	u16 pci_cmd, pci_bctl;
165 
166 	if (!hpx)
167 		hpx = &pci_default_type0;
168 
169 	if (hpx->revision > 1) {
170 		pci_warn(dev, "PCI settings rev %d not supported; using defaults\n",
171 			 hpx->revision);
172 		hpx = &pci_default_type0;
173 	}
174 
175 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpx->cache_line_size);
176 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpx->latency_timer);
177 	pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
178 	if (hpx->enable_serr)
179 		pci_cmd |= PCI_COMMAND_SERR;
180 	if (hpx->enable_perr)
181 		pci_cmd |= PCI_COMMAND_PARITY;
182 	pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
183 
184 	/* Program bridge control value */
185 	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
186 		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
187 				      hpx->latency_timer);
188 		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
189 		if (hpx->enable_perr)
190 			pci_bctl |= PCI_BRIDGE_CTL_PARITY;
191 		pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
192 	}
193 }
194 
195 static acpi_status decode_type0_hpx_record(union acpi_object *record,
196 					   struct hpx_type0 *hpx0)
197 {
198 	int i;
199 	union acpi_object *fields = record->package.elements;
200 	u32 revision = fields[1].integer.value;
201 
202 	switch (revision) {
203 	case 1:
204 		if (record->package.count != 6)
205 			return AE_ERROR;
206 		for (i = 2; i < 6; i++)
207 			if (fields[i].type != ACPI_TYPE_INTEGER)
208 				return AE_ERROR;
209 		hpx0->revision        = revision;
210 		hpx0->cache_line_size = fields[2].integer.value;
211 		hpx0->latency_timer   = fields[3].integer.value;
212 		hpx0->enable_serr     = fields[4].integer.value;
213 		hpx0->enable_perr     = fields[5].integer.value;
214 		break;
215 	default:
216 		pr_warn("%s: Type 0 Revision %d record not supported\n",
217 		       __func__, revision);
218 		return AE_ERROR;
219 	}
220 	return AE_OK;
221 }
222 
223 /* _HPX PCI-X Setting Record (Type 1) */
224 struct hpx_type1 {
225 	u32 revision;
226 	u8  max_mem_read;
227 	u8  avg_max_split;
228 	u16 tot_max_split;
229 };
230 
231 static void program_hpx_type1(struct pci_dev *dev, struct hpx_type1 *hpx)
232 {
233 	int pos;
234 
235 	if (!hpx)
236 		return;
237 
238 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
239 	if (!pos)
240 		return;
241 
242 	pci_warn(dev, "PCI-X settings not supported\n");
243 }
244 
245 static acpi_status decode_type1_hpx_record(union acpi_object *record,
246 					   struct hpx_type1 *hpx1)
247 {
248 	int i;
249 	union acpi_object *fields = record->package.elements;
250 	u32 revision = fields[1].integer.value;
251 
252 	switch (revision) {
253 	case 1:
254 		if (record->package.count != 5)
255 			return AE_ERROR;
256 		for (i = 2; i < 5; i++)
257 			if (fields[i].type != ACPI_TYPE_INTEGER)
258 				return AE_ERROR;
259 		hpx1->revision      = revision;
260 		hpx1->max_mem_read  = fields[2].integer.value;
261 		hpx1->avg_max_split = fields[3].integer.value;
262 		hpx1->tot_max_split = fields[4].integer.value;
263 		break;
264 	default:
265 		pr_warn("%s: Type 1 Revision %d record not supported\n",
266 		       __func__, revision);
267 		return AE_ERROR;
268 	}
269 	return AE_OK;
270 }
271 
272 static bool pcie_root_rcb_set(struct pci_dev *dev)
273 {
274 	struct pci_dev *rp = pcie_find_root_port(dev);
275 	u16 lnkctl;
276 
277 	if (!rp)
278 		return false;
279 
280 	pcie_capability_read_word(rp, PCI_EXP_LNKCTL, &lnkctl);
281 	if (lnkctl & PCI_EXP_LNKCTL_RCB)
282 		return true;
283 
284 	return false;
285 }
286 
287 /* _HPX PCI Express Setting Record (Type 2) */
288 struct hpx_type2 {
289 	u32 revision;
290 	u32 unc_err_mask_and;
291 	u32 unc_err_mask_or;
292 	u32 unc_err_sever_and;
293 	u32 unc_err_sever_or;
294 	u32 cor_err_mask_and;
295 	u32 cor_err_mask_or;
296 	u32 adv_err_cap_and;
297 	u32 adv_err_cap_or;
298 	u16 pci_exp_devctl_and;
299 	u16 pci_exp_devctl_or;
300 	u16 pci_exp_lnkctl_and;
301 	u16 pci_exp_lnkctl_or;
302 	u32 sec_unc_err_sever_and;
303 	u32 sec_unc_err_sever_or;
304 	u32 sec_unc_err_mask_and;
305 	u32 sec_unc_err_mask_or;
306 };
307 
308 static void program_hpx_type2(struct pci_dev *dev, struct hpx_type2 *hpx)
309 {
310 	int pos;
311 	u32 reg32;
312 
313 	if (!hpx)
314 		return;
315 
316 	if (!pci_is_pcie(dev))
317 		return;
318 
319 	if (hpx->revision > 1) {
320 		pci_warn(dev, "PCIe settings rev %d not supported\n",
321 			 hpx->revision);
322 		return;
323 	}
324 
325 	/*
326 	 * Don't allow _HPX to change MPS or MRRS settings.  We manage
327 	 * those to make sure they're consistent with the rest of the
328 	 * platform.
329 	 */
330 	hpx->pci_exp_devctl_and |= PCI_EXP_DEVCTL_PAYLOAD |
331 				    PCI_EXP_DEVCTL_READRQ;
332 	hpx->pci_exp_devctl_or &= ~(PCI_EXP_DEVCTL_PAYLOAD |
333 				    PCI_EXP_DEVCTL_READRQ);
334 
335 	/* Initialize Device Control Register */
336 	pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
337 			~hpx->pci_exp_devctl_and, hpx->pci_exp_devctl_or);
338 
339 	/* Initialize Link Control Register */
340 	if (pcie_cap_has_lnkctl(dev)) {
341 
342 		/*
343 		 * If the Root Port supports Read Completion Boundary of
344 		 * 128, set RCB to 128.  Otherwise, clear it.
345 		 */
346 		hpx->pci_exp_lnkctl_and |= PCI_EXP_LNKCTL_RCB;
347 		hpx->pci_exp_lnkctl_or &= ~PCI_EXP_LNKCTL_RCB;
348 		if (pcie_root_rcb_set(dev))
349 			hpx->pci_exp_lnkctl_or |= PCI_EXP_LNKCTL_RCB;
350 
351 		pcie_capability_clear_and_set_word(dev, PCI_EXP_LNKCTL,
352 			~hpx->pci_exp_lnkctl_and, hpx->pci_exp_lnkctl_or);
353 	}
354 
355 	/* Find Advanced Error Reporting Enhanced Capability */
356 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
357 	if (!pos)
358 		return;
359 
360 	/* Initialize Uncorrectable Error Mask Register */
361 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, &reg32);
362 	reg32 = (reg32 & hpx->unc_err_mask_and) | hpx->unc_err_mask_or;
363 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, reg32);
364 
365 	/* Initialize Uncorrectable Error Severity Register */
366 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &reg32);
367 	reg32 = (reg32 & hpx->unc_err_sever_and) | hpx->unc_err_sever_or;
368 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, reg32);
369 
370 	/* Initialize Correctable Error Mask Register */
371 	pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, &reg32);
372 	reg32 = (reg32 & hpx->cor_err_mask_and) | hpx->cor_err_mask_or;
373 	pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg32);
374 
375 	/* Initialize Advanced Error Capabilities and Control Register */
376 	pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
377 	reg32 = (reg32 & hpx->adv_err_cap_and) | hpx->adv_err_cap_or;
378 
379 	/* Don't enable ECRC generation or checking if unsupported */
380 	if (!(reg32 & PCI_ERR_CAP_ECRC_GENC))
381 		reg32 &= ~PCI_ERR_CAP_ECRC_GENE;
382 	if (!(reg32 & PCI_ERR_CAP_ECRC_CHKC))
383 		reg32 &= ~PCI_ERR_CAP_ECRC_CHKE;
384 	pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
385 
386 	/*
387 	 * FIXME: The following two registers are not supported yet.
388 	 *
389 	 *   o Secondary Uncorrectable Error Severity Register
390 	 *   o Secondary Uncorrectable Error Mask Register
391 	 */
392 }
393 
394 static acpi_status decode_type2_hpx_record(union acpi_object *record,
395 					   struct hpx_type2 *hpx2)
396 {
397 	int i;
398 	union acpi_object *fields = record->package.elements;
399 	u32 revision = fields[1].integer.value;
400 
401 	switch (revision) {
402 	case 1:
403 		if (record->package.count != 18)
404 			return AE_ERROR;
405 		for (i = 2; i < 18; i++)
406 			if (fields[i].type != ACPI_TYPE_INTEGER)
407 				return AE_ERROR;
408 		hpx2->revision      = revision;
409 		hpx2->unc_err_mask_and      = fields[2].integer.value;
410 		hpx2->unc_err_mask_or       = fields[3].integer.value;
411 		hpx2->unc_err_sever_and     = fields[4].integer.value;
412 		hpx2->unc_err_sever_or      = fields[5].integer.value;
413 		hpx2->cor_err_mask_and      = fields[6].integer.value;
414 		hpx2->cor_err_mask_or       = fields[7].integer.value;
415 		hpx2->adv_err_cap_and       = fields[8].integer.value;
416 		hpx2->adv_err_cap_or        = fields[9].integer.value;
417 		hpx2->pci_exp_devctl_and    = fields[10].integer.value;
418 		hpx2->pci_exp_devctl_or     = fields[11].integer.value;
419 		hpx2->pci_exp_lnkctl_and    = fields[12].integer.value;
420 		hpx2->pci_exp_lnkctl_or     = fields[13].integer.value;
421 		hpx2->sec_unc_err_sever_and = fields[14].integer.value;
422 		hpx2->sec_unc_err_sever_or  = fields[15].integer.value;
423 		hpx2->sec_unc_err_mask_and  = fields[16].integer.value;
424 		hpx2->sec_unc_err_mask_or   = fields[17].integer.value;
425 		break;
426 	default:
427 		pr_warn("%s: Type 2 Revision %d record not supported\n",
428 		       __func__, revision);
429 		return AE_ERROR;
430 	}
431 	return AE_OK;
432 }
433 
434 /* _HPX PCI Express Setting Record (Type 3) */
435 struct hpx_type3 {
436 	u16 device_type;
437 	u16 function_type;
438 	u16 config_space_location;
439 	u16 pci_exp_cap_id;
440 	u16 pci_exp_cap_ver;
441 	u16 pci_exp_vendor_id;
442 	u16 dvsec_id;
443 	u16 dvsec_rev;
444 	u16 match_offset;
445 	u32 match_mask_and;
446 	u32 match_value;
447 	u16 reg_offset;
448 	u32 reg_mask_and;
449 	u32 reg_mask_or;
450 };
451 
452 enum hpx_type3_dev_type {
453 	HPX_TYPE_ENDPOINT	= BIT(0),
454 	HPX_TYPE_LEG_END	= BIT(1),
455 	HPX_TYPE_RC_END		= BIT(2),
456 	HPX_TYPE_RC_EC		= BIT(3),
457 	HPX_TYPE_ROOT_PORT	= BIT(4),
458 	HPX_TYPE_UPSTREAM	= BIT(5),
459 	HPX_TYPE_DOWNSTREAM	= BIT(6),
460 	HPX_TYPE_PCI_BRIDGE	= BIT(7),
461 	HPX_TYPE_PCIE_BRIDGE	= BIT(8),
462 };
463 
464 static u16 hpx3_device_type(struct pci_dev *dev)
465 {
466 	u16 pcie_type = pci_pcie_type(dev);
467 	static const int pcie_to_hpx3_type[] = {
468 		[PCI_EXP_TYPE_ENDPOINT]    = HPX_TYPE_ENDPOINT,
469 		[PCI_EXP_TYPE_LEG_END]     = HPX_TYPE_LEG_END,
470 		[PCI_EXP_TYPE_RC_END]      = HPX_TYPE_RC_END,
471 		[PCI_EXP_TYPE_RC_EC]       = HPX_TYPE_RC_EC,
472 		[PCI_EXP_TYPE_ROOT_PORT]   = HPX_TYPE_ROOT_PORT,
473 		[PCI_EXP_TYPE_UPSTREAM]    = HPX_TYPE_UPSTREAM,
474 		[PCI_EXP_TYPE_DOWNSTREAM]  = HPX_TYPE_DOWNSTREAM,
475 		[PCI_EXP_TYPE_PCI_BRIDGE]  = HPX_TYPE_PCI_BRIDGE,
476 		[PCI_EXP_TYPE_PCIE_BRIDGE] = HPX_TYPE_PCIE_BRIDGE,
477 	};
478 
479 	if (pcie_type >= ARRAY_SIZE(pcie_to_hpx3_type))
480 		return 0;
481 
482 	return pcie_to_hpx3_type[pcie_type];
483 }
484 
485 enum hpx_type3_fn_type {
486 	HPX_FN_NORMAL		= BIT(0),
487 	HPX_FN_SRIOV_PHYS	= BIT(1),
488 	HPX_FN_SRIOV_VIRT	= BIT(2),
489 };
490 
491 static u8 hpx3_function_type(struct pci_dev *dev)
492 {
493 	if (dev->is_virtfn)
494 		return HPX_FN_SRIOV_VIRT;
495 	else if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV) > 0)
496 		return HPX_FN_SRIOV_PHYS;
497 	else
498 		return HPX_FN_NORMAL;
499 }
500 
501 static bool hpx3_cap_ver_matches(u8 pcie_cap_id, u8 hpx3_cap_id)
502 {
503 	u8 cap_ver = hpx3_cap_id & 0xf;
504 
505 	if ((hpx3_cap_id & BIT(4)) && cap_ver >= pcie_cap_id)
506 		return true;
507 	else if (cap_ver == pcie_cap_id)
508 		return true;
509 
510 	return false;
511 }
512 
513 enum hpx_type3_cfg_loc {
514 	HPX_CFG_PCICFG		= 0,
515 	HPX_CFG_PCIE_CAP	= 1,
516 	HPX_CFG_PCIE_CAP_EXT	= 2,
517 	HPX_CFG_VEND_CAP	= 3,
518 	HPX_CFG_DVSEC		= 4,
519 	HPX_CFG_MAX,
520 };
521 
522 static void program_hpx_type3_register(struct pci_dev *dev,
523 				       const struct hpx_type3 *reg)
524 {
525 	u32 match_reg, write_reg, header, orig_value;
526 	u16 pos;
527 
528 	if (!(hpx3_device_type(dev) & reg->device_type))
529 		return;
530 
531 	if (!(hpx3_function_type(dev) & reg->function_type))
532 		return;
533 
534 	switch (reg->config_space_location) {
535 	case HPX_CFG_PCICFG:
536 		pos = 0;
537 		break;
538 	case HPX_CFG_PCIE_CAP:
539 		pos = pci_find_capability(dev, reg->pci_exp_cap_id);
540 		if (pos == 0)
541 			return;
542 
543 		break;
544 	case HPX_CFG_PCIE_CAP_EXT:
545 		pos = pci_find_ext_capability(dev, reg->pci_exp_cap_id);
546 		if (pos == 0)
547 			return;
548 
549 		pci_read_config_dword(dev, pos, &header);
550 		if (!hpx3_cap_ver_matches(PCI_EXT_CAP_VER(header),
551 					  reg->pci_exp_cap_ver))
552 			return;
553 
554 		break;
555 	case HPX_CFG_VEND_CAP:
556 	case HPX_CFG_DVSEC:
557 	default:
558 		pci_warn(dev, "Encountered _HPX type 3 with unsupported config space location");
559 		return;
560 	}
561 
562 	pci_read_config_dword(dev, pos + reg->match_offset, &match_reg);
563 
564 	if ((match_reg & reg->match_mask_and) != reg->match_value)
565 		return;
566 
567 	pci_read_config_dword(dev, pos + reg->reg_offset, &write_reg);
568 	orig_value = write_reg;
569 	write_reg &= reg->reg_mask_and;
570 	write_reg |= reg->reg_mask_or;
571 
572 	if (orig_value == write_reg)
573 		return;
574 
575 	pci_write_config_dword(dev, pos + reg->reg_offset, write_reg);
576 
577 	pci_dbg(dev, "Applied _HPX3 at [0x%x]: 0x%08x -> 0x%08x",
578 		pos, orig_value, write_reg);
579 }
580 
581 static void program_hpx_type3(struct pci_dev *dev, struct hpx_type3 *hpx)
582 {
583 	if (!hpx)
584 		return;
585 
586 	if (!pci_is_pcie(dev))
587 		return;
588 
589 	program_hpx_type3_register(dev, hpx);
590 }
591 
592 static void parse_hpx3_register(struct hpx_type3 *hpx3_reg,
593 				union acpi_object *reg_fields)
594 {
595 	hpx3_reg->device_type            = reg_fields[0].integer.value;
596 	hpx3_reg->function_type          = reg_fields[1].integer.value;
597 	hpx3_reg->config_space_location  = reg_fields[2].integer.value;
598 	hpx3_reg->pci_exp_cap_id         = reg_fields[3].integer.value;
599 	hpx3_reg->pci_exp_cap_ver        = reg_fields[4].integer.value;
600 	hpx3_reg->pci_exp_vendor_id      = reg_fields[5].integer.value;
601 	hpx3_reg->dvsec_id               = reg_fields[6].integer.value;
602 	hpx3_reg->dvsec_rev              = reg_fields[7].integer.value;
603 	hpx3_reg->match_offset           = reg_fields[8].integer.value;
604 	hpx3_reg->match_mask_and         = reg_fields[9].integer.value;
605 	hpx3_reg->match_value            = reg_fields[10].integer.value;
606 	hpx3_reg->reg_offset             = reg_fields[11].integer.value;
607 	hpx3_reg->reg_mask_and           = reg_fields[12].integer.value;
608 	hpx3_reg->reg_mask_or            = reg_fields[13].integer.value;
609 }
610 
611 static acpi_status program_type3_hpx_record(struct pci_dev *dev,
612 					   union acpi_object *record)
613 {
614 	union acpi_object *fields = record->package.elements;
615 	u32 desc_count, expected_length, revision;
616 	union acpi_object *reg_fields;
617 	struct hpx_type3 hpx3;
618 	int i;
619 
620 	revision = fields[1].integer.value;
621 	switch (revision) {
622 	case 1:
623 		desc_count = fields[2].integer.value;
624 		expected_length = 3 + desc_count * 14;
625 
626 		if (record->package.count != expected_length)
627 			return AE_ERROR;
628 
629 		for (i = 2; i < expected_length; i++)
630 			if (fields[i].type != ACPI_TYPE_INTEGER)
631 				return AE_ERROR;
632 
633 		for (i = 0; i < desc_count; i++) {
634 			reg_fields = fields + 3 + i * 14;
635 			parse_hpx3_register(&hpx3, reg_fields);
636 			program_hpx_type3(dev, &hpx3);
637 		}
638 
639 		break;
640 	default:
641 		printk(KERN_WARNING
642 			"%s: Type 3 Revision %d record not supported\n",
643 			__func__, revision);
644 		return AE_ERROR;
645 	}
646 	return AE_OK;
647 }
648 
649 static acpi_status acpi_run_hpx(struct pci_dev *dev, acpi_handle handle)
650 {
651 	acpi_status status;
652 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
653 	union acpi_object *package, *record, *fields;
654 	struct hpx_type0 hpx0;
655 	struct hpx_type1 hpx1;
656 	struct hpx_type2 hpx2;
657 	u32 type;
658 	int i;
659 
660 	status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
661 	if (ACPI_FAILURE(status))
662 		return status;
663 
664 	package = (union acpi_object *)buffer.pointer;
665 	if (package->type != ACPI_TYPE_PACKAGE) {
666 		status = AE_ERROR;
667 		goto exit;
668 	}
669 
670 	for (i = 0; i < package->package.count; i++) {
671 		record = &package->package.elements[i];
672 		if (record->type != ACPI_TYPE_PACKAGE) {
673 			status = AE_ERROR;
674 			goto exit;
675 		}
676 
677 		fields = record->package.elements;
678 		if (fields[0].type != ACPI_TYPE_INTEGER ||
679 		    fields[1].type != ACPI_TYPE_INTEGER) {
680 			status = AE_ERROR;
681 			goto exit;
682 		}
683 
684 		type = fields[0].integer.value;
685 		switch (type) {
686 		case 0:
687 			memset(&hpx0, 0, sizeof(hpx0));
688 			status = decode_type0_hpx_record(record, &hpx0);
689 			if (ACPI_FAILURE(status))
690 				goto exit;
691 			program_hpx_type0(dev, &hpx0);
692 			break;
693 		case 1:
694 			memset(&hpx1, 0, sizeof(hpx1));
695 			status = decode_type1_hpx_record(record, &hpx1);
696 			if (ACPI_FAILURE(status))
697 				goto exit;
698 			program_hpx_type1(dev, &hpx1);
699 			break;
700 		case 2:
701 			memset(&hpx2, 0, sizeof(hpx2));
702 			status = decode_type2_hpx_record(record, &hpx2);
703 			if (ACPI_FAILURE(status))
704 				goto exit;
705 			program_hpx_type2(dev, &hpx2);
706 			break;
707 		case 3:
708 			status = program_type3_hpx_record(dev, record);
709 			if (ACPI_FAILURE(status))
710 				goto exit;
711 			break;
712 		default:
713 			pr_err("%s: Type %d record not supported\n",
714 			       __func__, type);
715 			status = AE_ERROR;
716 			goto exit;
717 		}
718 	}
719  exit:
720 	kfree(buffer.pointer);
721 	return status;
722 }
723 
724 static acpi_status acpi_run_hpp(struct pci_dev *dev, acpi_handle handle)
725 {
726 	acpi_status status;
727 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
728 	union acpi_object *package, *fields;
729 	struct hpx_type0 hpx0;
730 	int i;
731 
732 	memset(&hpx0, 0, sizeof(hpx0));
733 
734 	status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer);
735 	if (ACPI_FAILURE(status))
736 		return status;
737 
738 	package = (union acpi_object *) buffer.pointer;
739 	if (package->type != ACPI_TYPE_PACKAGE ||
740 	    package->package.count != 4) {
741 		status = AE_ERROR;
742 		goto exit;
743 	}
744 
745 	fields = package->package.elements;
746 	for (i = 0; i < 4; i++) {
747 		if (fields[i].type != ACPI_TYPE_INTEGER) {
748 			status = AE_ERROR;
749 			goto exit;
750 		}
751 	}
752 
753 	hpx0.revision        = 1;
754 	hpx0.cache_line_size = fields[0].integer.value;
755 	hpx0.latency_timer   = fields[1].integer.value;
756 	hpx0.enable_serr     = fields[2].integer.value;
757 	hpx0.enable_perr     = fields[3].integer.value;
758 
759 	program_hpx_type0(dev, &hpx0);
760 
761 exit:
762 	kfree(buffer.pointer);
763 	return status;
764 }
765 
766 /* pci_acpi_program_hp_params
767  *
768  * @dev - the pci_dev for which we want parameters
769  */
770 int pci_acpi_program_hp_params(struct pci_dev *dev)
771 {
772 	acpi_status status;
773 	acpi_handle handle, phandle;
774 	struct pci_bus *pbus;
775 
776 	if (acpi_pci_disabled)
777 		return -ENODEV;
778 
779 	handle = NULL;
780 	for (pbus = dev->bus; pbus; pbus = pbus->parent) {
781 		handle = acpi_pci_get_bridge_handle(pbus);
782 		if (handle)
783 			break;
784 	}
785 
786 	/*
787 	 * _HPP settings apply to all child buses, until another _HPP is
788 	 * encountered. If we don't find an _HPP for the input pci dev,
789 	 * look for it in the parent device scope since that would apply to
790 	 * this pci dev.
791 	 */
792 	while (handle) {
793 		status = acpi_run_hpx(dev, handle);
794 		if (ACPI_SUCCESS(status))
795 			return 0;
796 		status = acpi_run_hpp(dev, handle);
797 		if (ACPI_SUCCESS(status))
798 			return 0;
799 		if (acpi_is_root_bridge(handle))
800 			break;
801 		status = acpi_get_parent(handle, &phandle);
802 		if (ACPI_FAILURE(status))
803 			break;
804 		handle = phandle;
805 	}
806 	return -ENODEV;
807 }
808 
809 /**
810  * pciehp_is_native - Check whether a hotplug port is handled by the OS
811  * @bridge: Hotplug port to check
812  *
813  * Returns true if the given @bridge is handled by the native PCIe hotplug
814  * driver.
815  */
816 bool pciehp_is_native(struct pci_dev *bridge)
817 {
818 	const struct pci_host_bridge *host;
819 	u32 slot_cap;
820 
821 	if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
822 		return false;
823 
824 	pcie_capability_read_dword(bridge, PCI_EXP_SLTCAP, &slot_cap);
825 	if (!(slot_cap & PCI_EXP_SLTCAP_HPC))
826 		return false;
827 
828 	if (pcie_ports_native)
829 		return true;
830 
831 	host = pci_find_host_bridge(bridge->bus);
832 	return host->native_pcie_hotplug;
833 }
834 
835 /**
836  * shpchp_is_native - Check whether a hotplug port is handled by the OS
837  * @bridge: Hotplug port to check
838  *
839  * Returns true if the given @bridge is handled by the native SHPC hotplug
840  * driver.
841  */
842 bool shpchp_is_native(struct pci_dev *bridge)
843 {
844 	return bridge->shpc_managed;
845 }
846 
847 /**
848  * pci_acpi_wake_bus - Root bus wakeup notification fork function.
849  * @context: Device wakeup context.
850  */
851 static void pci_acpi_wake_bus(struct acpi_device_wakeup_context *context)
852 {
853 	struct acpi_device *adev;
854 	struct acpi_pci_root *root;
855 
856 	adev = container_of(context, struct acpi_device, wakeup.context);
857 	root = acpi_driver_data(adev);
858 	pci_pme_wakeup_bus(root->bus);
859 }
860 
861 /**
862  * pci_acpi_wake_dev - PCI device wakeup notification work function.
863  * @context: Device wakeup context.
864  */
865 static void pci_acpi_wake_dev(struct acpi_device_wakeup_context *context)
866 {
867 	struct pci_dev *pci_dev;
868 
869 	pci_dev = to_pci_dev(context->dev);
870 
871 	if (pci_dev->pme_poll)
872 		pci_dev->pme_poll = false;
873 
874 	if (pci_dev->current_state == PCI_D3cold) {
875 		pci_wakeup_event(pci_dev);
876 		pm_request_resume(&pci_dev->dev);
877 		return;
878 	}
879 
880 	/* Clear PME Status if set. */
881 	if (pci_dev->pme_support)
882 		pci_check_pme_status(pci_dev);
883 
884 	pci_wakeup_event(pci_dev);
885 	pm_request_resume(&pci_dev->dev);
886 
887 	pci_pme_wakeup_bus(pci_dev->subordinate);
888 }
889 
890 /**
891  * pci_acpi_add_bus_pm_notifier - Register PM notifier for root PCI bus.
892  * @dev: PCI root bridge ACPI device.
893  */
894 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev)
895 {
896 	return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus);
897 }
898 
899 /**
900  * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
901  * @dev: ACPI device to add the notifier for.
902  * @pci_dev: PCI device to check for the PME status if an event is signaled.
903  */
904 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
905 				     struct pci_dev *pci_dev)
906 {
907 	return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev);
908 }
909 
910 /*
911  * _SxD returns the D-state with the highest power
912  * (lowest D-state number) supported in the S-state "x".
913  *
914  * If the devices does not have a _PRW
915  * (Power Resources for Wake) supporting system wakeup from "x"
916  * then the OS is free to choose a lower power (higher number
917  * D-state) than the return value from _SxD.
918  *
919  * But if _PRW is enabled at S-state "x", the OS
920  * must not choose a power lower than _SxD --
921  * unless the device has an _SxW method specifying
922  * the lowest power (highest D-state number) the device
923  * may enter while still able to wake the system.
924  *
925  * ie. depending on global OS policy:
926  *
927  * if (_PRW at S-state x)
928  *	choose from highest power _SxD to lowest power _SxW
929  * else // no _PRW at S-state x
930  *	choose highest power _SxD or any lower power
931  */
932 
933 pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
934 {
935 	int acpi_state, d_max;
936 
937 	if (pdev->no_d3cold || !pdev->d3cold_allowed)
938 		d_max = ACPI_STATE_D3_HOT;
939 	else
940 		d_max = ACPI_STATE_D3_COLD;
941 	acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max);
942 	if (acpi_state < 0)
943 		return PCI_POWER_ERROR;
944 
945 	switch (acpi_state) {
946 	case ACPI_STATE_D0:
947 		return PCI_D0;
948 	case ACPI_STATE_D1:
949 		return PCI_D1;
950 	case ACPI_STATE_D2:
951 		return PCI_D2;
952 	case ACPI_STATE_D3_HOT:
953 		return PCI_D3hot;
954 	case ACPI_STATE_D3_COLD:
955 		return PCI_D3cold;
956 	}
957 	return PCI_POWER_ERROR;
958 }
959 
960 static struct acpi_device *acpi_pci_find_companion(struct device *dev);
961 
962 void pci_set_acpi_fwnode(struct pci_dev *dev)
963 {
964 	if (!dev_fwnode(&dev->dev) && !pci_dev_is_added(dev))
965 		ACPI_COMPANION_SET(&dev->dev,
966 				   acpi_pci_find_companion(&dev->dev));
967 }
968 
969 /**
970  * pci_dev_acpi_reset - do a function level reset using _RST method
971  * @dev: device to reset
972  * @probe: if true, return 0 if device supports _RST
973  */
974 int pci_dev_acpi_reset(struct pci_dev *dev, bool probe)
975 {
976 	acpi_handle handle = ACPI_HANDLE(&dev->dev);
977 
978 	if (!handle || !acpi_has_method(handle, "_RST"))
979 		return -ENOTTY;
980 
981 	if (probe)
982 		return 0;
983 
984 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_RST", NULL, NULL))) {
985 		pci_warn(dev, "ACPI _RST failed\n");
986 		return -ENOTTY;
987 	}
988 
989 	return 0;
990 }
991 
992 bool acpi_pci_power_manageable(struct pci_dev *dev)
993 {
994 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
995 
996 	return adev && acpi_device_power_manageable(adev);
997 }
998 
999 bool acpi_pci_bridge_d3(struct pci_dev *dev)
1000 {
1001 	struct pci_dev *rpdev;
1002 	struct acpi_device *adev, *rpadev;
1003 	const union acpi_object *obj;
1004 
1005 	if (acpi_pci_disabled || !dev->is_hotplug_bridge)
1006 		return false;
1007 
1008 	adev = ACPI_COMPANION(&dev->dev);
1009 	if (adev) {
1010 		/*
1011 		 * If the bridge has _S0W, whether or not it can go into D3
1012 		 * depends on what is returned by that object.  In particular,
1013 		 * if the power state returned by _S0W is D2 or shallower,
1014 		 * entering D3 should not be allowed.
1015 		 */
1016 		if (acpi_dev_power_state_for_wake(adev) <= ACPI_STATE_D2)
1017 			return false;
1018 
1019 		/*
1020 		 * Otherwise, assume that the bridge can enter D3 so long as it
1021 		 * is power-manageable via ACPI.
1022 		 */
1023 		if (acpi_device_power_manageable(adev))
1024 			return true;
1025 	}
1026 
1027 	rpdev = pcie_find_root_port(dev);
1028 	if (!rpdev)
1029 		return false;
1030 
1031 	if (rpdev == dev)
1032 		rpadev = adev;
1033 	else
1034 		rpadev = ACPI_COMPANION(&rpdev->dev);
1035 
1036 	if (!rpadev)
1037 		return false;
1038 
1039 	/*
1040 	 * If the Root Port cannot signal wakeup signals at all, i.e., it
1041 	 * doesn't supply a wakeup GPE via _PRW, it cannot signal hotplug
1042 	 * events from low-power states including D3hot and D3cold.
1043 	 */
1044 	if (!rpadev->wakeup.flags.valid)
1045 		return false;
1046 
1047 	/*
1048 	 * In the bridge-below-a-Root-Port case, evaluate _S0W for the Root Port
1049 	 * to verify whether or not it can signal wakeup from D3.
1050 	 */
1051 	if (rpadev != adev &&
1052 	    acpi_dev_power_state_for_wake(rpadev) <= ACPI_STATE_D2)
1053 		return false;
1054 
1055 	/*
1056 	 * The "HotPlugSupportInD3" property in a Root Port _DSD indicates
1057 	 * the Port can signal hotplug events while in D3.  We assume any
1058 	 * bridges *below* that Root Port can also signal hotplug events
1059 	 * while in D3.
1060 	 */
1061 	if (!acpi_dev_get_property(rpadev, "HotPlugSupportInD3",
1062 				   ACPI_TYPE_INTEGER, &obj) &&
1063 	    obj->integer.value == 1)
1064 		return true;
1065 
1066 	return false;
1067 }
1068 
1069 static void acpi_pci_config_space_access(struct pci_dev *dev, bool enable)
1070 {
1071 	int val = enable ? ACPI_REG_CONNECT : ACPI_REG_DISCONNECT;
1072 	int ret = acpi_evaluate_reg(ACPI_HANDLE(&dev->dev),
1073 				    ACPI_ADR_SPACE_PCI_CONFIG, val);
1074 	if (ret)
1075 		pci_dbg(dev, "ACPI _REG %s evaluation failed (%d)\n",
1076 			enable ? "connect" : "disconnect", ret);
1077 }
1078 
1079 int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
1080 {
1081 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
1082 	static const u8 state_conv[] = {
1083 		[PCI_D0] = ACPI_STATE_D0,
1084 		[PCI_D1] = ACPI_STATE_D1,
1085 		[PCI_D2] = ACPI_STATE_D2,
1086 		[PCI_D3hot] = ACPI_STATE_D3_HOT,
1087 		[PCI_D3cold] = ACPI_STATE_D3_COLD,
1088 	};
1089 	int error;
1090 
1091 	/* If the ACPI device has _EJ0, ignore the device */
1092 	if (!adev || acpi_has_method(adev->handle, "_EJ0"))
1093 		return -ENODEV;
1094 
1095 	switch (state) {
1096 	case PCI_D0:
1097 	case PCI_D1:
1098 	case PCI_D2:
1099 	case PCI_D3hot:
1100 	case PCI_D3cold:
1101 		break;
1102 	default:
1103 		return -EINVAL;
1104 	}
1105 
1106 	if (state == PCI_D3cold) {
1107 		if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) ==
1108 				PM_QOS_FLAGS_ALL)
1109 			return -EBUSY;
1110 
1111 		/* Notify AML lack of PCI config space availability */
1112 		acpi_pci_config_space_access(dev, false);
1113 	}
1114 
1115 	error = acpi_device_set_power(adev, state_conv[state]);
1116 	if (error)
1117 		return error;
1118 
1119 	pci_dbg(dev, "power state changed by ACPI to %s\n",
1120 	        acpi_power_state_string(adev->power.state));
1121 
1122 	/*
1123 	 * Notify AML of PCI config space availability.  Config space is
1124 	 * accessible in all states except D3cold; the only transitions
1125 	 * that change availability are transitions to D3cold and from
1126 	 * D3cold to D0.
1127 	 */
1128 	if (state == PCI_D0)
1129 		acpi_pci_config_space_access(dev, true);
1130 
1131 	return 0;
1132 }
1133 
1134 pci_power_t acpi_pci_get_power_state(struct pci_dev *dev)
1135 {
1136 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
1137 	static const pci_power_t state_conv[] = {
1138 		[ACPI_STATE_D0]      = PCI_D0,
1139 		[ACPI_STATE_D1]      = PCI_D1,
1140 		[ACPI_STATE_D2]      = PCI_D2,
1141 		[ACPI_STATE_D3_HOT]  = PCI_D3hot,
1142 		[ACPI_STATE_D3_COLD] = PCI_D3cold,
1143 	};
1144 	int state;
1145 
1146 	if (!adev || !acpi_device_power_manageable(adev))
1147 		return PCI_UNKNOWN;
1148 
1149 	state = adev->power.state;
1150 	if (state == ACPI_STATE_UNKNOWN)
1151 		return PCI_UNKNOWN;
1152 
1153 	return state_conv[state];
1154 }
1155 
1156 void acpi_pci_refresh_power_state(struct pci_dev *dev)
1157 {
1158 	struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
1159 
1160 	if (adev && acpi_device_power_manageable(adev))
1161 		acpi_device_update_power(adev, NULL);
1162 }
1163 
1164 static int acpi_pci_propagate_wakeup(struct pci_bus *bus, bool enable)
1165 {
1166 	while (bus->parent) {
1167 		if (acpi_pm_device_can_wakeup(&bus->self->dev))
1168 			return acpi_pm_set_device_wakeup(&bus->self->dev, enable);
1169 
1170 		bus = bus->parent;
1171 	}
1172 
1173 	/* We have reached the root bus. */
1174 	if (bus->bridge) {
1175 		if (acpi_pm_device_can_wakeup(bus->bridge))
1176 			return acpi_pm_set_device_wakeup(bus->bridge, enable);
1177 	}
1178 	return 0;
1179 }
1180 
1181 int acpi_pci_wakeup(struct pci_dev *dev, bool enable)
1182 {
1183 	if (acpi_pci_disabled)
1184 		return 0;
1185 
1186 	if (acpi_pm_device_can_wakeup(&dev->dev))
1187 		return acpi_pm_set_device_wakeup(&dev->dev, enable);
1188 
1189 	return acpi_pci_propagate_wakeup(dev->bus, enable);
1190 }
1191 
1192 bool acpi_pci_need_resume(struct pci_dev *dev)
1193 {
1194 	struct acpi_device *adev;
1195 
1196 	if (acpi_pci_disabled)
1197 		return false;
1198 
1199 	/*
1200 	 * In some cases (eg. Samsung 305V4A) leaving a bridge in suspend over
1201 	 * system-wide suspend/resume confuses the platform firmware, so avoid
1202 	 * doing that.  According to Section 16.1.6 of ACPI 6.2, endpoint
1203 	 * devices are expected to be in D3 before invoking the S3 entry path
1204 	 * from the firmware, so they should not be affected by this issue.
1205 	 */
1206 	if (pci_is_bridge(dev) && acpi_target_system_state() != ACPI_STATE_S0)
1207 		return true;
1208 
1209 	adev = ACPI_COMPANION(&dev->dev);
1210 	if (!adev || !acpi_device_power_manageable(adev))
1211 		return false;
1212 
1213 	if (adev->wakeup.flags.valid &&
1214 	    device_may_wakeup(&dev->dev) != !!adev->wakeup.prepare_count)
1215 		return true;
1216 
1217 	if (acpi_target_system_state() == ACPI_STATE_S0)
1218 		return false;
1219 
1220 	return !!adev->power.flags.dsw_present;
1221 }
1222 
1223 void acpi_pci_add_bus(struct pci_bus *bus)
1224 {
1225 	union acpi_object *obj;
1226 	struct pci_host_bridge *bridge;
1227 
1228 	if (acpi_pci_disabled || !bus->bridge || !ACPI_HANDLE(bus->bridge))
1229 		return;
1230 
1231 	acpi_pci_slot_enumerate(bus);
1232 	acpiphp_enumerate_slots(bus);
1233 
1234 	/*
1235 	 * For a host bridge, check its _DSM for function 8 and if
1236 	 * that is available, mark it in pci_host_bridge.
1237 	 */
1238 	if (!pci_is_root_bus(bus))
1239 		return;
1240 
1241 	obj = acpi_evaluate_dsm_typed(ACPI_HANDLE(bus->bridge), &pci_acpi_dsm_guid, 3,
1242 				      DSM_PCI_POWER_ON_RESET_DELAY, NULL, ACPI_TYPE_INTEGER);
1243 	if (!obj)
1244 		return;
1245 
1246 	if (obj->integer.value == 1) {
1247 		bridge = pci_find_host_bridge(bus);
1248 		bridge->ignore_reset_delay = 1;
1249 	}
1250 	ACPI_FREE(obj);
1251 }
1252 
1253 void acpi_pci_remove_bus(struct pci_bus *bus)
1254 {
1255 	if (acpi_pci_disabled || !bus->bridge)
1256 		return;
1257 
1258 	acpiphp_remove_slots(bus);
1259 	acpi_pci_slot_remove(bus);
1260 }
1261 
1262 /* ACPI bus type */
1263 
1264 
1265 static DECLARE_RWSEM(pci_acpi_companion_lookup_sem);
1266 static struct acpi_device *(*pci_acpi_find_companion_hook)(struct pci_dev *);
1267 
1268 /**
1269  * pci_acpi_set_companion_lookup_hook - Set ACPI companion lookup callback.
1270  * @func: ACPI companion lookup callback pointer or NULL.
1271  *
1272  * Set a special ACPI companion lookup callback for PCI devices whose companion
1273  * objects in the ACPI namespace have _ADR with non-standard bus-device-function
1274  * encodings.
1275  *
1276  * Return 0 on success or a negative error code on failure (in which case no
1277  * changes are made).
1278  *
1279  * The caller is responsible for the appropriate ordering of the invocations of
1280  * this function with respect to the enumeration of the PCI devices needing the
1281  * callback installed by it.
1282  */
1283 int pci_acpi_set_companion_lookup_hook(struct acpi_device *(*func)(struct pci_dev *))
1284 {
1285 	int ret;
1286 
1287 	if (!func)
1288 		return -EINVAL;
1289 
1290 	down_write(&pci_acpi_companion_lookup_sem);
1291 
1292 	if (pci_acpi_find_companion_hook) {
1293 		ret = -EBUSY;
1294 	} else {
1295 		pci_acpi_find_companion_hook = func;
1296 		ret = 0;
1297 	}
1298 
1299 	up_write(&pci_acpi_companion_lookup_sem);
1300 
1301 	return ret;
1302 }
1303 EXPORT_SYMBOL_GPL(pci_acpi_set_companion_lookup_hook);
1304 
1305 /**
1306  * pci_acpi_clear_companion_lookup_hook - Clear ACPI companion lookup callback.
1307  *
1308  * Clear the special ACPI companion lookup callback previously set by
1309  * pci_acpi_set_companion_lookup_hook().  Block until the last running instance
1310  * of the callback returns before clearing it.
1311  *
1312  * The caller is responsible for the appropriate ordering of the invocations of
1313  * this function with respect to the enumeration of the PCI devices needing the
1314  * callback cleared by it.
1315  */
1316 void pci_acpi_clear_companion_lookup_hook(void)
1317 {
1318 	down_write(&pci_acpi_companion_lookup_sem);
1319 
1320 	pci_acpi_find_companion_hook = NULL;
1321 
1322 	up_write(&pci_acpi_companion_lookup_sem);
1323 }
1324 EXPORT_SYMBOL_GPL(pci_acpi_clear_companion_lookup_hook);
1325 
1326 static struct acpi_device *acpi_pci_find_companion(struct device *dev)
1327 {
1328 	struct pci_dev *pci_dev = to_pci_dev(dev);
1329 	struct acpi_device *adev;
1330 	bool check_children;
1331 	u64 addr;
1332 
1333 	if (!dev->parent)
1334 		return NULL;
1335 
1336 	down_read(&pci_acpi_companion_lookup_sem);
1337 
1338 	adev = pci_acpi_find_companion_hook ?
1339 		pci_acpi_find_companion_hook(pci_dev) : NULL;
1340 
1341 	up_read(&pci_acpi_companion_lookup_sem);
1342 
1343 	if (adev)
1344 		return adev;
1345 
1346 	check_children = pci_is_bridge(pci_dev);
1347 	/* Please ref to ACPI spec for the syntax of _ADR */
1348 	addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
1349 	adev = acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
1350 				      check_children);
1351 
1352 	/*
1353 	 * There may be ACPI device objects in the ACPI namespace that are
1354 	 * children of the device object representing the host bridge, but don't
1355 	 * represent PCI devices.  Both _HID and _ADR may be present for them,
1356 	 * even though that is against the specification (for example, see
1357 	 * Section 6.1 of ACPI 6.3), but in many cases the _ADR returns 0 which
1358 	 * appears to indicate that they should not be taken into consideration
1359 	 * as potential companions of PCI devices on the root bus.
1360 	 *
1361 	 * To catch this special case, disregard the returned device object if
1362 	 * it has a valid _HID, addr is 0 and the PCI device at hand is on the
1363 	 * root bus.
1364 	 */
1365 	if (adev && adev->pnp.type.platform_id && !addr &&
1366 	    pci_is_root_bus(pci_dev->bus))
1367 		return NULL;
1368 
1369 	return adev;
1370 }
1371 
1372 /**
1373  * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
1374  * @pdev: the PCI device whose delay is to be updated
1375  * @handle: ACPI handle of this device
1376  *
1377  * Update the d3hot_delay and d3cold_delay of a PCI device from the ACPI _DSM
1378  * control method of either the device itself or the PCI host bridge.
1379  *
1380  * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
1381  * host bridge.  If it returns one, the OS may assume that all devices in
1382  * the hierarchy have already completed power-on reset delays.
1383  *
1384  * Function 9, "Device Readiness Durations," applies only to the object
1385  * where it is located.  It returns delay durations required after various
1386  * events if the device requires less time than the spec requires.  Delays
1387  * from this function take precedence over the Reset Delay function.
1388  *
1389  * These _DSM functions are defined by the draft ECN of January 28, 2014,
1390  * titled "ACPI additions for FW latency optimizations."
1391  */
1392 static void pci_acpi_optimize_delay(struct pci_dev *pdev,
1393 				    acpi_handle handle)
1394 {
1395 	struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
1396 	int value;
1397 	union acpi_object *obj, *elements;
1398 
1399 	if (bridge->ignore_reset_delay)
1400 		pdev->d3cold_delay = 0;
1401 
1402 	obj = acpi_evaluate_dsm_typed(handle, &pci_acpi_dsm_guid, 3,
1403 				      DSM_PCI_DEVICE_READINESS_DURATIONS, NULL,
1404 				      ACPI_TYPE_PACKAGE);
1405 	if (!obj)
1406 		return;
1407 
1408 	if (obj->package.count == 5) {
1409 		elements = obj->package.elements;
1410 		if (elements[0].type == ACPI_TYPE_INTEGER) {
1411 			value = (int)elements[0].integer.value / 1000;
1412 			if (value < PCI_PM_D3COLD_WAIT)
1413 				pdev->d3cold_delay = value;
1414 		}
1415 		if (elements[3].type == ACPI_TYPE_INTEGER) {
1416 			value = (int)elements[3].integer.value / 1000;
1417 			if (value < PCI_PM_D3HOT_WAIT)
1418 				pdev->d3hot_delay = value;
1419 		}
1420 	}
1421 	ACPI_FREE(obj);
1422 }
1423 
1424 static void pci_acpi_set_external_facing(struct pci_dev *dev)
1425 {
1426 	u8 val;
1427 
1428 	if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
1429 		return;
1430 	if (device_property_read_u8(&dev->dev, "ExternalFacingPort", &val))
1431 		return;
1432 
1433 	/*
1434 	 * These root ports expose PCIe (including DMA) outside of the
1435 	 * system.  Everything downstream from them is external.
1436 	 */
1437 	if (val)
1438 		dev->external_facing = 1;
1439 }
1440 
1441 void pci_acpi_setup(struct device *dev, struct acpi_device *adev)
1442 {
1443 	struct pci_dev *pci_dev = to_pci_dev(dev);
1444 
1445 	pci_acpi_optimize_delay(pci_dev, adev->handle);
1446 	pci_acpi_set_external_facing(pci_dev);
1447 	pci_acpi_add_edr_notifier(pci_dev);
1448 
1449 	pci_acpi_add_pm_notifier(adev, pci_dev);
1450 	if (!adev->wakeup.flags.valid)
1451 		return;
1452 
1453 	device_set_wakeup_capable(dev, true);
1454 	/*
1455 	 * For bridges that can do D3 we enable wake automatically (as
1456 	 * we do for the power management itself in that case). The
1457 	 * reason is that the bridge may have additional methods such as
1458 	 * _DSW that need to be called.
1459 	 */
1460 	if (pci_dev->bridge_d3)
1461 		device_wakeup_enable(dev);
1462 
1463 	acpi_pci_wakeup(pci_dev, false);
1464 	acpi_device_power_add_dependent(adev, dev);
1465 
1466 	if (pci_is_bridge(pci_dev))
1467 		acpi_dev_power_up_children_with_adr(adev);
1468 }
1469 
1470 void pci_acpi_cleanup(struct device *dev, struct acpi_device *adev)
1471 {
1472 	struct pci_dev *pci_dev = to_pci_dev(dev);
1473 
1474 	pci_acpi_remove_edr_notifier(pci_dev);
1475 	pci_acpi_remove_pm_notifier(adev);
1476 	if (adev->wakeup.flags.valid) {
1477 		acpi_device_power_remove_dependent(adev, dev);
1478 		if (pci_dev->bridge_d3)
1479 			device_wakeup_disable(dev);
1480 
1481 		device_set_wakeup_capable(dev, false);
1482 	}
1483 }
1484 
1485 static struct fwnode_handle *(*pci_msi_get_fwnode_cb)(struct device *dev);
1486 
1487 /**
1488  * pci_msi_register_fwnode_provider - Register callback to retrieve fwnode
1489  * @fn:       Callback matching a device to a fwnode that identifies a PCI
1490  *            MSI domain.
1491  *
1492  * This should be called by irqchip driver, which is the parent of
1493  * the MSI domain to provide callback interface to query fwnode.
1494  */
1495 void
1496 pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *))
1497 {
1498 	pci_msi_get_fwnode_cb = fn;
1499 }
1500 
1501 /**
1502  * pci_host_bridge_acpi_msi_domain - Retrieve MSI domain of a PCI host bridge
1503  * @bus:      The PCI host bridge bus.
1504  *
1505  * This function uses the callback function registered by
1506  * pci_msi_register_fwnode_provider() to retrieve the irq_domain with
1507  * type DOMAIN_BUS_PCI_MSI of the specified host bridge bus.
1508  * This returns NULL on error or when the domain is not found.
1509  */
1510 struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus)
1511 {
1512 	struct fwnode_handle *fwnode;
1513 
1514 	if (!pci_msi_get_fwnode_cb)
1515 		return NULL;
1516 
1517 	fwnode = pci_msi_get_fwnode_cb(&bus->dev);
1518 	if (!fwnode)
1519 		return NULL;
1520 
1521 	return irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
1522 }
1523 
1524 static int __init acpi_pci_init(void)
1525 {
1526 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
1527 		pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n");
1528 		pci_no_msi();
1529 	}
1530 
1531 	if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
1532 		pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
1533 		pcie_no_aspm();
1534 	}
1535 
1536 	if (acpi_pci_disabled)
1537 		return 0;
1538 
1539 	acpi_pci_slot_init();
1540 	acpiphp_init();
1541 
1542 	return 0;
1543 }
1544 arch_initcall(acpi_pci_init);
1545 
1546 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
1547 
1548 /*
1549  * Try to assign the IRQ number when probing a new device
1550  */
1551 int pcibios_alloc_irq(struct pci_dev *dev)
1552 {
1553 	if (!acpi_disabled)
1554 		acpi_pci_irq_enable(dev);
1555 
1556 	return 0;
1557 }
1558 
1559 struct acpi_pci_generic_root_info {
1560 	struct acpi_pci_root_info	common;
1561 	struct pci_config_window	*cfg;	/* config space mapping */
1562 };
1563 
1564 int acpi_pci_bus_find_domain_nr(struct pci_bus *bus)
1565 {
1566 	struct pci_config_window *cfg = bus->sysdata;
1567 	struct acpi_device *adev = to_acpi_device(cfg->parent);
1568 	struct acpi_pci_root *root = acpi_driver_data(adev);
1569 
1570 	return root->segment;
1571 }
1572 
1573 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
1574 {
1575 	struct pci_config_window *cfg;
1576 	struct acpi_device *adev;
1577 	struct device *bus_dev;
1578 
1579 	if (acpi_disabled)
1580 		return 0;
1581 
1582 	cfg = bridge->bus->sysdata;
1583 
1584 	/*
1585 	 * On Hyper-V there is no corresponding ACPI device for a root bridge,
1586 	 * therefore ->parent is set as NULL by the driver. And set 'adev' as
1587 	 * NULL in this case because there is no proper ACPI device.
1588 	 */
1589 	if (!cfg->parent)
1590 		adev = NULL;
1591 	else
1592 		adev = to_acpi_device(cfg->parent);
1593 
1594 	bus_dev = &bridge->bus->dev;
1595 
1596 	ACPI_COMPANION_SET(&bridge->dev, adev);
1597 	set_dev_node(bus_dev, acpi_get_node(acpi_device_handle(adev)));
1598 
1599 	return 0;
1600 }
1601 
1602 static int pci_acpi_root_prepare_resources(struct acpi_pci_root_info *ci)
1603 {
1604 	struct resource_entry *entry, *tmp;
1605 	int status;
1606 
1607 	status = acpi_pci_probe_root_resources(ci);
1608 	resource_list_for_each_entry_safe(entry, tmp, &ci->resources) {
1609 		if (!(entry->res->flags & IORESOURCE_WINDOW))
1610 			resource_list_destroy_entry(entry);
1611 	}
1612 	return status;
1613 }
1614 
1615 /*
1616  * Lookup the bus range for the domain in MCFG, and set up config space
1617  * mapping.
1618  */
1619 static struct pci_config_window *
1620 pci_acpi_setup_ecam_mapping(struct acpi_pci_root *root)
1621 {
1622 	struct device *dev = &root->device->dev;
1623 	struct resource *bus_res = &root->secondary;
1624 	u16 seg = root->segment;
1625 	const struct pci_ecam_ops *ecam_ops;
1626 	struct resource cfgres;
1627 	struct acpi_device *adev;
1628 	struct pci_config_window *cfg;
1629 	int ret;
1630 
1631 	ret = pci_mcfg_lookup(root, &cfgres, &ecam_ops);
1632 	if (ret) {
1633 		dev_err(dev, "%04x:%pR ECAM region not found\n", seg, bus_res);
1634 		return NULL;
1635 	}
1636 
1637 	adev = acpi_resource_consumer(&cfgres);
1638 	if (adev)
1639 		dev_info(dev, "ECAM area %pR reserved by %s\n", &cfgres,
1640 			 dev_name(&adev->dev));
1641 	else
1642 		dev_warn(dev, FW_BUG "ECAM area %pR not reserved in ACPI namespace\n",
1643 			 &cfgres);
1644 
1645 	cfg = pci_ecam_create(dev, &cfgres, bus_res, ecam_ops);
1646 	if (IS_ERR(cfg)) {
1647 		dev_err(dev, "%04x:%pR error %ld mapping ECAM\n", seg, bus_res,
1648 			PTR_ERR(cfg));
1649 		return NULL;
1650 	}
1651 
1652 	return cfg;
1653 }
1654 
1655 /* release_info: free resources allocated by init_info */
1656 static void pci_acpi_generic_release_info(struct acpi_pci_root_info *ci)
1657 {
1658 	struct acpi_pci_generic_root_info *ri;
1659 
1660 	ri = container_of(ci, struct acpi_pci_generic_root_info, common);
1661 	pci_ecam_free(ri->cfg);
1662 	kfree(ci->ops);
1663 	kfree(ri);
1664 }
1665 
1666 /* Interface called from ACPI code to setup PCI host controller */
1667 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
1668 {
1669 	struct acpi_pci_generic_root_info *ri;
1670 	struct pci_bus *bus, *child;
1671 	struct acpi_pci_root_ops *root_ops;
1672 	struct pci_host_bridge *host;
1673 
1674 	ri = kzalloc(sizeof(*ri), GFP_KERNEL);
1675 	if (!ri)
1676 		return NULL;
1677 
1678 	root_ops = kzalloc(sizeof(*root_ops), GFP_KERNEL);
1679 	if (!root_ops) {
1680 		kfree(ri);
1681 		return NULL;
1682 	}
1683 
1684 	ri->cfg = pci_acpi_setup_ecam_mapping(root);
1685 	if (!ri->cfg) {
1686 		kfree(ri);
1687 		kfree(root_ops);
1688 		return NULL;
1689 	}
1690 
1691 	root_ops->release_info = pci_acpi_generic_release_info;
1692 	root_ops->prepare_resources = pci_acpi_root_prepare_resources;
1693 	root_ops->pci_ops = (struct pci_ops *)&ri->cfg->ops->pci_ops;
1694 	bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg);
1695 	if (!bus)
1696 		return NULL;
1697 
1698 	/* If we must preserve the resource configuration, claim now */
1699 	host = pci_find_host_bridge(bus);
1700 	if (host->preserve_config)
1701 		pci_bus_claim_resources(bus);
1702 
1703 	/*
1704 	 * Assign whatever was left unassigned. If we didn't claim above,
1705 	 * this will reassign everything.
1706 	 */
1707 	pci_assign_unassigned_root_bus_resources(bus);
1708 
1709 	list_for_each_entry(child, &bus->children, node)
1710 		pcie_bus_configure_settings(child);
1711 
1712 	return bus;
1713 }
1714 
1715 void pcibios_add_bus(struct pci_bus *bus)
1716 {
1717 	acpi_pci_add_bus(bus);
1718 }
1719 
1720 void pcibios_remove_bus(struct pci_bus *bus)
1721 {
1722 	acpi_pci_remove_bus(bus);
1723 }
1724 
1725 #endif
1726