linux-stable/drivers/pci/pcie/portdrv_acpi.c
Rafael J. Wysocki 415e12b237 PCI/ACPI: Request _OSC control once for each root bridge (v3)
Move the evaluation of acpi_pci_osc_control_set() (to request control of
PCI Express native features) into acpi_pci_root_add() to avoid calling
it many times for the same root complex with the same arguments.
Additionally, check if all of the requisite _OSC support bits are set
before calling acpi_pci_osc_control_set() for a given root complex.

References: https://bugzilla.kernel.org/show_bug.cgi?id=20232
Reported-by: Ozan Caglayan <ozan@pardus.org.tr>
Tested-by: Ozan Caglayan <ozan@pardus.org.tr>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-01-14 08:55:41 -08:00

62 lines
1.8 KiB
C

/*
* PCIe Port Native Services Support, ACPI-Related Part
*
* Copyright (C) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License V2. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/acpi.h>
#include <linux/pci-acpi.h>
#include <linux/pcieport_if.h>
#include "aer/aerdrv.h"
#include "../pci.h"
/**
* pcie_port_acpi_setup - Request the BIOS to release control of PCIe services.
* @port: PCIe Port service for a root port or event collector.
* @srv_mask: Bit mask of services that can be enabled for @port.
*
* Invoked when @port is identified as a PCIe port device. To avoid conflicts
* with the BIOS PCIe port native services support requires the BIOS to yield
* control of these services to the kernel. The mask of services that the BIOS
* allows to be enabled for @port is written to @srv_mask.
*
* NOTE: It turns out that we cannot do that for individual port services
* separately, because that would make some systems work incorrectly.
*/
int pcie_port_acpi_setup(struct pci_dev *port, int *srv_mask)
{
struct acpi_pci_root *root;
acpi_handle handle;
u32 flags;
if (acpi_pci_disabled)
return 0;
handle = acpi_find_root_bridge_handle(port);
if (!handle)
return -EINVAL;
root = acpi_pci_find_root(handle);
if (!root)
return -ENODEV;
flags = root->osc_control_set;
*srv_mask = PCIE_PORT_SERVICE_VC;
if (flags & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)
*srv_mask |= PCIE_PORT_SERVICE_HP;
if (flags & OSC_PCI_EXPRESS_PME_CONTROL)
*srv_mask |= PCIE_PORT_SERVICE_PME;
if (flags & OSC_PCI_EXPRESS_AER_CONTROL)
*srv_mask |= PCIE_PORT_SERVICE_AER;
return 0;
}