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 = NULL;
  35
  36         if (acpi_pci_disabled)
  37                 return -1;
  38
  39         /* Find root host bridge */
  40         while (pdev->bus->self)
  41                 pdev = pdev->bus->self;
  42         handle = acpi_get_pci_rootbridge_handle(
  43                 pci_domain_nr(pdev->bus), pdev->bus->number);
  44
  45         if (handle) {
  46                 pcie_osc_support_set(OSC_EXT_PCI_CONFIG_SUPPORT);
  47                 status = pci_osc_control_set(handle,
  48                                         OSC_PCI_EXPRESS_AER_CONTROL |
  49                                         OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
  50         }
  51
  52         if (ACPI_FAILURE(status)) {
  53                 printk(KERN_DEBUG "AER service couldn't init device %s - %s\n",
  54                     pciedev->device.bus_id,
  55                     (status == AE_SUPPORT || status == AE_NOT_FOUND) ?
  56                     "no _OSC support" : "Run ACPI _OSC fails");
  57                 return -1;
  58         }
  59
  60         return 0;
  61 }