tools/power/cpupower/utils/helpers/pci.c

   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__) */