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   ACPI_HEST_SEGMENT(p->bus) == pci_domain_nr(pci->bus) &&
  27                  ACPI_HEST_BUS(p->bus)     == pci->bus->number &&
  28                  p->device                 == PCI_SLOT(pci->devfn) &&
  29                  p->function               == PCI_FUNC(pci->devfn);
  30 }
  31
  32 static inline bool hest_match_type(struct acpi_hest_header *hest_hdr,
  33                                 struct pci_dev *dev)
  34 {
  35         u16 hest_type = hest_hdr->type;
  36         u8 pcie_type = pci_pcie_type(dev);
  37
  38         if ((hest_type == ACPI_HEST_TYPE_AER_ROOT_PORT &&
  39                 pcie_type == PCI_EXP_TYPE_ROOT_PORT) ||
  40             (hest_type == ACPI_HEST_TYPE_AER_ENDPOINT &&
  41                 pcie_type == PCI_EXP_TYPE_ENDPOINT) ||
  42             (hest_type == ACPI_HEST_TYPE_AER_BRIDGE &&
  43                 (dev->class >> 16) == PCI_BASE_CLASS_BRIDGE))
  44                 return true;
  45         return false;
  46 }
  47
  48 struct aer_hest_parse_info {
  49         struct pci_dev *pci_dev;
  50         int firmware_first;
  51 };
  52
  53 static int hest_source_is_pcie_aer(struct acpi_hest_header *hest_hdr)
  54 {
  55         if (hest_hdr->type == ACPI_HEST_TYPE_AER_ROOT_PORT ||
  56             hest_hdr->type == ACPI_HEST_TYPE_AER_ENDPOINT ||
  57             hest_hdr->type == ACPI_HEST_TYPE_AER_BRIDGE)
  58                 return 1;
  59         return 0;
  60 }
  61
  62 static int aer_hest_parse(struct acpi_hest_header *hest_hdr, void *data)
  63 {
  64         struct aer_hest_parse_info *info = data;
  65         struct acpi_hest_aer_common *p;
  66         int ff;
  67
  68         if (!hest_source_is_pcie_aer(hest_hdr))
  69                 return 0;
  70
  71         p = (struct acpi_hest_aer_common *)(hest_hdr + 1);
  72         ff = !!(p->flags & ACPI_HEST_FIRMWARE_FIRST);
  73
  74         /*
  75          * If no specific device is supplied, determine whether
  76          * FIRMWARE_FIRST is set for *any* PCIe device.
  77          */
  78         if (!info->pci_dev) {
  79                 info->firmware_first |= ff;
  80                 return 0;
  81         }
  82
  83         /* Otherwise, check the specific device */
  84         if (p->flags & ACPI_HEST_GLOBAL) {
  85                 if (hest_match_type(hest_hdr, info->pci_dev))
  86                         info->firmware_first = ff;
  87         } else
  88                 if (hest_match_pci(p, info->pci_dev))
  89                         info->firmware_first = ff;
  90
  91         return 0;
  92 }
  93
  94 static void aer_set_firmware_first(struct pci_dev *pci_dev)
  95 {
  96         int rc;
  97         struct aer_hest_parse_info info = {
  98                 .pci_dev        = pci_dev,
  99                 .firmware_first = 0,
 100         };
 101
 102         rc = apei_hest_parse(aer_hest_parse, &info);
 103
 104         if (rc)
 105                 pci_dev->__aer_firmware_first = 0;
 106         else
 107                 pci_dev->__aer_firmware_first = info.firmware_first;
 108         pci_dev->__aer_firmware_first_valid = 1;
 109 }
 110
 111 int pcie_aer_get_firmware_first(struct pci_dev *dev)
 112 {
 113         if (!pci_is_pcie(dev))
 114                 return 0;
 115
 116         if (!dev->__aer_firmware_first_valid)
 117                 aer_set_firmware_first(dev);
 118         return dev->__aer_firmware_first;
 119 }
 120
 121 static bool aer_firmware_first;
 122
 123 /**
 124  * aer_acpi_firmware_first - Check if APEI should control AER.
 125  */
 126 bool aer_acpi_firmware_first(void)
 127 {
 128         static bool parsed = false;
 129         struct aer_hest_parse_info info = {
 130                 .pci_dev        = NULL, /* Check all PCIe devices */
 131                 .firmware_first = 0,
 132         };
 133
 134         if (!parsed) {
 135                 apei_hest_parse(aer_hest_parse, &info);
 136                 aer_firmware_first = info.firmware_first;
 137                 parsed = true;
 138         }
 139         return aer_firmware_first;
 140 }
 141 #endif