src/device/pci_ops.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <stdint.h>
   4 #include <console/console.h>
   5 #include <device/pci.h>
   6 #include <device/pci_ops.h>
   7
   8 u8 *const pci_mmconf = (void *)(uintptr_t)CONFIG_ECAM_MMCONF_BASE_ADDRESS;
   9
  10 /**
  11  * Given a device, a capability type, and a last position, return the next
  12  * matching capability. Always start at the head of the list.
  13  *
  14  * @param dev Pointer to the device structure.
  15  * @param cap PCI_CAP_LIST_ID of the PCI capability we're looking for.
  16  * @param last Location of the PCI capability register to start from.
  17  * @return The next matching capability.
  18  */
  19 u16 pci_s_find_next_capability(pci_devfn_t dev, u16 cap, u16 last)
  20 {
  21         u16 pos = 0;
  22         u16 status;
  23         int reps = 48;
  24
  25         status = pci_s_read_config16(dev, PCI_STATUS);
  26         if (!(status & PCI_STATUS_CAP_LIST))
  27                 return 0;
  28
  29         u8 hdr_type = pci_s_read_config8(dev, PCI_HEADER_TYPE);
  30         switch (hdr_type & 0x7f) {
  31         case PCI_HEADER_TYPE_NORMAL:
  32         case PCI_HEADER_TYPE_BRIDGE:
  33                 pos = PCI_CAPABILITY_LIST;
  34                 break;
  35         case PCI_HEADER_TYPE_CARDBUS:
  36                 pos = PCI_CB_CAPABILITY_LIST;
  37                 break;
  38         default:
  39                 return 0;
  40         }
  41
  42         pos = pci_s_read_config8(dev, pos);
  43         while (reps-- && (pos >= 0x40)) { /* Loop through the linked list. */
  44                 int this_cap;
  45
  46                 pos &= ~3;
  47                 this_cap = pci_s_read_config8(dev, pos + PCI_CAP_LIST_ID);
  48                 if (this_cap == 0xff)
  49                         break;
  50
  51                 if (!last && (this_cap == cap))
  52                         return pos;
  53
  54                 if (last == pos)
  55                         last = 0;
  56
  57                 pos = pci_s_read_config8(dev, pos + PCI_CAP_LIST_NEXT);
  58         }
  59         return 0;
  60 }
  61
  62 /**
  63  * Given a device, and a capability type, return the next matching
  64  * capability. Always start at the head of the list.
  65  *
  66  * @param dev Pointer to the device structure.
  67  * @param cap PCI_CAP_LIST_ID of the PCI capability we're looking for.
  68  * @return The next matching capability.
  69  */
  70 u16 pci_s_find_capability(pci_devfn_t dev, u16 cap)
  71 {
  72         return pci_s_find_next_capability(dev, cap, 0);
  73 }
  74
  75 void __noreturn pcidev_die(void)
  76 {
  77         die("PCI: dev is NULL!\n");
  78 }
  79
  80 bool pci_dev_is_wake_source(pci_devfn_t dev)
  81 {
  82         unsigned int pm_cap;
  83         uint16_t pmcs;
  84
  85         pm_cap = pci_s_find_capability(dev, PCI_CAP_ID_PM);
  86         if (!pm_cap)
  87                 return false;
  88
  89         pmcs = pci_s_read_config16(dev, pm_cap + PCI_PM_CTRL);
  90
  91         /* PCI Device is a wake source if PME_ENABLE and PME_STATUS are set in PMCS register. */
  92         return (pmcs & PCI_PM_CTRL_PME_ENABLE) && (pmcs & PCI_PM_CTRL_PME_STATUS);
  93 }