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  * @pciedev: pcie_device which AER is being enabled on
  24  *
  25  * @return: Zero on success. Nonzero 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 pcie_device *pciedev)
  31 {
  32         acpi_status status = AE_NOT_FOUND;
  33         struct pci_dev *pdev = pciedev->port;
  34         acpi_handle handle = DEVICE_ACPI_HANDLE(&pdev->dev);
  35         struct pci_bus *parent;
  36
  37         while (!handle) {
  38                 if (!pdev || !pdev->bus->parent)
  39                         break;
  40                 parent = pdev->bus->parent;
  41                 if (!parent->self)
  42                         /* Parent must be a host bridge */
  43                         handle = acpi_get_pci_rootbridge_handle(
  44                                         pci_domain_nr(parent),
  45                                         parent->number);
  46                 else
  47                         handle = DEVICE_ACPI_HANDLE(
  48                                         &(parent->self->dev));
  49                 pdev = parent->self;
  50         }
  51
  52         if (handle) {
  53                 pci_osc_support_set(OSC_EXT_PCI_CONFIG_SUPPORT);
  54                 status = pci_osc_control_set(handle,
  55                                         OSC_PCI_EXPRESS_AER_CONTROL |
  56                                         OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
  57         }
  58
  59         if (ACPI_FAILURE(status)) {
  60                 printk(KERN_DEBUG "AER service couldn't init device %s - %s\n",
  61                     pciedev->device.bus_id,
  62                     (status == AE_SUPPORT || status == AE_NOT_FOUND) ?
  63                     "no _OSC support" : "Run ACPI _OSC fails");
  64                 return -1;
  65         }
  66
  67         return 0;
  68 }