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 "aerdrv.h"
  20
  21 /**
  22  * aer_osc_setup - run ACPI _OSC method
  23  *
  24  * Return:
  25  *      Zero if success. Nonzero for otherwise.
  26  *
  27  * Invoked when PCIE bus loads AER service driver. To avoid conflict with
  28  * BIOS AER support requires BIOS to yield AER control to OS native driver.
  29  **/
  30 int aer_osc_setup(struct pci_dev *dev)
  31 {
  32         int retval = OSC_METHOD_RUN_SUCCESS;
  33         acpi_status status;
  34         acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
  35         struct pci_dev *pdev = dev;
  36         struct pci_bus *parent;
  37
  38         while (!handle) {
  39                 if (!pdev || !pdev->bus->parent)
  40                         break;
  41                 parent = pdev->bus->parent;
  42                 if (!parent->self)
  43                         /* Parent must be a host bridge */
  44                         handle = acpi_get_pci_rootbridge_handle(
  45                                         pci_domain_nr(parent),
  46                                         parent->number);
  47                 else
  48                         handle = DEVICE_ACPI_HANDLE(
  49                                         &(parent->self->dev));
  50                 pdev = parent->self;
  51         }
  52
  53         if (!handle)
  54                 return OSC_METHOD_NOT_SUPPORTED;
  55
  56         pci_osc_support_set(OSC_EXT_PCI_CONFIG_SUPPORT);
  57         status = pci_osc_control_set(handle, OSC_PCI_EXPRESS_AER_CONTROL |
  58                 OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
  59         if (ACPI_FAILURE(status)) {
  60                 if (status == AE_SUPPORT)
  61                         retval = OSC_METHOD_NOT_SUPPORTED;
  62                 else
  63                         retval = OSC_METHOD_RUN_FAILURE;
  64         }
  65
  66         return retval;
  67 }
  68