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