linux/drivers/pci/pcie/aer/aerdrv_acpi.c
Andrew Patterson 3c75e23784 PCI: Run ACPI _OSC method on root bridges only
According to the PCI Firmware Specification Revision 3.0 section 4.5, _OSC
should only be called on a root brdige.  Here is the relevant passage: "The
_OSC interface defined in this section applies only to Host Bridge ACPI
devices that originate PCI, PCI-X, or PCI Express hierarchies". Changed the
code to find the parent root bridge of the device and call _OSC on that.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-01 15:04:30 -08:00

58 lines
1.5 KiB
C

/*
* Access ACPI _OSC method
*
* Copyright (C) 2006 Intel Corp.
* Tom Long Nguyen (tom.l.nguyen@intel.com)
* Zhang Yanmin (yanmin.zhang@intel.com)
*
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/pm.h>
#include <linux/suspend.h>
#include <linux/acpi.h>
#include <linux/pci-acpi.h>
#include <linux/delay.h>
#include "aerdrv.h"
/**
* aer_osc_setup - run ACPI _OSC method
* @pciedev: pcie_device which AER is being enabled on
*
* @return: Zero on success. Nonzero otherwise.
*
* Invoked when PCIE bus loads AER service driver. To avoid conflict with
* BIOS AER support requires BIOS to yield AER control to OS native driver.
**/
int aer_osc_setup(struct pcie_device *pciedev)
{
acpi_status status = AE_NOT_FOUND;
struct pci_dev *pdev = pciedev->port;
acpi_handle handle = 0;
/* Find root host bridge */
while (pdev->bus && pdev->bus->self)
pdev = pdev->bus->self;
handle = acpi_get_pci_rootbridge_handle(
pci_domain_nr(pdev->bus), pdev->bus->number);
if (handle) {
pcie_osc_support_set(OSC_EXT_PCI_CONFIG_SUPPORT);
status = pci_osc_control_set(handle,
OSC_PCI_EXPRESS_AER_CONTROL |
OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
}
if (ACPI_FAILURE(status)) {
printk(KERN_DEBUG "AER service couldn't init device %s - %s\n",
pciedev->device.bus_id,
(status == AE_SUPPORT || status == AE_NOT_FOUND) ?
"no _OSC support" : "Run ACPI _OSC fails");
return -1;
}
return 0;
}