1 // SPDX-License-Identifier: GPL-2.0
2 #if defined(__i386__) || defined(__x86_64__)
3 
4 #include <helpers/helpers.h>
5 
6 /*
7  * pci_acc_init
8  *
9  * PCI access helper function depending on libpci
10  *
11  * **pacc : if a valid pci_dev is returned
12  *         *pacc must be passed to pci_acc_cleanup to free it
13  *
14  * domain: domain
15  * bus:    bus
16  * slot:   slot
17  * func:   func
18  * vendor: vendor
19  * device: device
20  * Pass -1 for one of the six above to match any
21  *
22  * Returns :
23  * struct pci_dev which can be used with pci_{read,write}_* functions
24  *                to access the PCI config space of matching pci devices
25  */
26 struct pci_dev *pci_acc_init(struct pci_access **pacc, int domain, int bus,
27 			     int slot, int func, int vendor, int dev)
28 {
29 	struct pci_filter filter_nb_link;
30 	struct pci_dev *device;
31 
32 	*pacc = pci_alloc();
33 	if (*pacc == NULL)
34 		return NULL;
35 
36 	pci_filter_init(*pacc, &filter_nb_link);
37 	filter_nb_link.domain	= domain;
38 	filter_nb_link.bus	= bus;
39 	filter_nb_link.slot	= slot;
40 	filter_nb_link.func	= func;
41 	filter_nb_link.vendor	= vendor;
42 	filter_nb_link.device	= dev;
43 
44 	pci_init(*pacc);
45 	pci_scan_bus(*pacc);
46 
47 	for (device = (*pacc)->devices; device; device = device->next) {
48 		if (pci_filter_match(&filter_nb_link, device))
49 			return device;
50 	}
51 	pci_cleanup(*pacc);
52 	return NULL;
53 }
54 
55 /* Typically one wants to get a specific slot(device)/func of the root domain
56    and bus */
57 struct pci_dev *pci_slot_func_init(struct pci_access **pacc, int slot,
58 				       int func)
59 {
60 	return pci_acc_init(pacc, 0, 0, slot, func, -1, -1);
61 }
62 
63 #endif /* defined(__i386__) || defined(__x86_64__) */
64