drivers/pci/pcie/aer/aerdrv_acpi.c

   1 /*
   2  * Access ACPI _OSC method
   3  *
   4  * Copyright (C) 2006 Intel Corp.
   5  *      Tom Long Nguyen (tom.l.nguyen@intel.com)
   6  *      Zhang Yanmin (yanmin.zhang@intel.com)
   7  *
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/pci.h>
  12 #include <linux/kernel.h>
  13 #include <linux/errno.h>
  14 #include <linux/pm.h>
  15 #include <linux/suspend.h>
  16 #include <linux/acpi.h>
  17 #include <linux/pci-acpi.h>
  18 #include <linux/delay.h>
  19 #include <acpi/apei.h>
  20 #include "aerdrv.h"
  21
  22 #ifdef CONFIG_ACPI_APEI
  23 static inline int hest_match_pci(struct acpi_hest_aer_common *p,
  24                                  struct pci_dev *pci)
  25 {
  26         return  (0           == pci_domain_nr(pci->bus) &&
  27                  p->bus      == pci->bus->number &&
  28                  p->device   == PCI_SLOT(pci->devfn) &&
  29                  p->function == PCI_FUNC(pci->devfn));
  30 }
  31
  32 struct aer_hest_parse_info {
  33         struct pci_dev *pci_dev;
  34         int firmware_first;
  35 };
  36
  37 static int aer_hest_parse(struct acpi_hest_header *hest_hdr, void *data)
  38 {
  39         struct aer_hest_parse_info *info = data;
  40         struct acpi_hest_aer_common *p;
  41         u8 pcie_type = 0;
  42         u8 bridge = 0;
  43         int ff = 0;
  44
  45         switch (hest_hdr->type) {
  46         case ACPI_HEST_TYPE_AER_ROOT_PORT:
  47                 pcie_type = PCI_EXP_TYPE_ROOT_PORT;
  48                 break;
  49         case ACPI_HEST_TYPE_AER_ENDPOINT:
  50                 pcie_type = PCI_EXP_TYPE_ENDPOINT;
  51                 break;
  52         case ACPI_HEST_TYPE_AER_BRIDGE:
  53                 if ((info->pci_dev->class >> 16) == PCI_BASE_CLASS_BRIDGE)
  54                         bridge = 1;
  55                 break;
  56         default:
  57                 return 0;
  58         }
  59
  60         p = (struct acpi_hest_aer_common *)(hest_hdr + 1);
  61         if (p->flags & ACPI_HEST_GLOBAL) {
  62                 if ((info->pci_dev->is_pcie &&
  63                      info->pci_dev->pcie_type == pcie_type) || bridge)
  64                         ff = !!(p->flags & ACPI_HEST_FIRMWARE_FIRST);
  65         } else
  66                 if (hest_match_pci(p, info->pci_dev))
  67                         ff = !!(p->flags & ACPI_HEST_FIRMWARE_FIRST);
  68         info->firmware_first = ff;
  69
  70         return 0;
  71 }
  72
  73 static void aer_set_firmware_first(struct pci_dev *pci_dev)
  74 {
  75         int rc;
  76         struct aer_hest_parse_info info = {
  77                 .pci_dev        = pci_dev,
  78                 .firmware_first = 0,
  79         };
  80
  81         rc = apei_hest_parse(aer_hest_parse, &info);
  82
  83         if (rc)
  84                 pci_dev->__aer_firmware_first = 0;
  85         else
  86                 pci_dev->__aer_firmware_first = info.firmware_first;
  87         pci_dev->__aer_firmware_first_valid = 1;
  88 }
  89
  90 int pcie_aer_get_firmware_first(struct pci_dev *dev)
  91 {
  92         if (!dev->__aer_firmware_first_valid)
  93                 aer_set_firmware_first(dev);
  94         return dev->__aer_firmware_first;
  95 }
  96
  97 static bool aer_firmware_first;
  98
  99 static int aer_hest_parse_aff(struct acpi_hest_header *hest_hdr, void *data)
 100 {
 101         struct acpi_hest_aer_common *p;
 102
 103         if (aer_firmware_first)
 104                 return 0;
 105
 106         switch (hest_hdr->type) {
 107         case ACPI_HEST_TYPE_AER_ROOT_PORT:
 108         case ACPI_HEST_TYPE_AER_ENDPOINT:
 109         case ACPI_HEST_TYPE_AER_BRIDGE:
 110                 p = (struct acpi_hest_aer_common *)(hest_hdr + 1);
 111                 aer_firmware_first = !!(p->flags & ACPI_HEST_FIRMWARE_FIRST);
 112         default:
 113                 return 0;
 114         }
 115 }
 116
 117 /**
 118  * aer_acpi_firmware_first - Check if APEI should control AER.
 119  */
 120 bool aer_acpi_firmware_first(void)
 121 {
 122         static bool parsed = false;
 123
 124         if (!parsed) {
 125                 apei_hest_parse(aer_hest_parse_aff, NULL);
 126                 parsed = true;
 127         }
 128         return aer_firmware_first;
 129 }
 130 #endif