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linux_old1/drivers/pci/pcie/portdrv_acpi.c

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PCI: PCIe: Ask BIOS for control of all native services at once After commit 852972acff8f10f3a15679be2059bb94916cba5d (ACPI: Disable ASPM if the platform won't provide _OSC control for PCIe) control of the PCIe Capability Structure is unconditionally requested by acpi_pci_root_add(), which in principle may cause problems to happen in two ways. First, the BIOS may refuse to give control of the PCIe Capability Structure if it is not asked for any of the _OSC features depending on it at the same time. Second, the BIOS may assume that control of the _OSC features depending on the PCIe Capability Structure will be requested in the future and may behave incorrectly if that doesn't happen. For this reason, control of the PCIe Capability Structure should always be requested along with control of any other _OSC features that may depend on it (ie. PCIe native PME, PCIe native hot-plug, PCIe AER). Rework the PCIe port driver so that (1) it checks which native PCIe port services can be enabled, according to the BIOS, and (2) it requests control of all these services simultaneously. In particular, this causes pcie_portdrv_probe() to fail if the BIOS refuses to grant control of the PCIe Capability Structure, which means that no native PCIe port services can be enabled for the PCIe Root Complex the given port belongs to. If that happens, ASPM is disabled to avoid problems with mishandling it by the part of the PCIe hierarchy for which control of the PCIe Capability Structure has not been received. Make it possible to override this behavior using 'pcie_ports=native' (use the PCIe native services regardless of the BIOS response to the control request), or 'pcie_ports=compat' (do not use the PCIe native services at all). Accordingly, rework the existing PCIe port service drivers so that they don't request control of the services directly. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-08-22 04:02:38 +08:00
/*
* 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)
{
acpi_status status;
acpi_handle handle;
u32 flags;
if (acpi_pci_disabled)
return 0;
handle = acpi_find_root_bridge_handle(port);
if (!handle)
return -EINVAL;
flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
| OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
| OSC_PCI_EXPRESS_PME_CONTROL;
if (pci_aer_available()) {
PCI/PCIe/AER: Disable native AER service if BIOS has precedence There is a design issue related to PCIe AER and _OSC that the BIOS may be asked to grant control of the AER service even if some Hardware Error Source Table (HEST) entries contain information meaning that the BIOS really should control it. Namely, pcie_port_acpi_setup() calls pcie_aer_get_firmware_first() that determines whether or not the AER service should be controlled by the BIOS on the basis of the HEST information for the given PCIe port. The BIOS is asked to grant control of the AER service for a PCIe Root Complex if pcie_aer_get_firmware_first() returns 'false' for at least one root port in that complex, even if all of the other root ports' HEST entries have the FIRMWARE_FIRST flag set (and none of them has the GLOBAL flag set). However, if the AER service is controlled by the kernel, that may interfere with the BIOS' handling of the error sources having the FIRMWARE_FIRST flag. Moreover, there may be PCIe endpoints that have the FIRMWARE_FIRST flag set in HEST and are attached to the root ports in question, in which case it also may be unsafe to ask the BIOS for control of the AER service. For this reason, introduce a function checking if there's at least one PCIe-related HEST entry with the FIRMWARE_FIRST flag set and disable the native AER service altogether if this function returns 'true'. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-09-21 00:50:00 +08:00
if (aer_acpi_firmware_first())
PCI: PCIe: Ask BIOS for control of all native services at once After commit 852972acff8f10f3a15679be2059bb94916cba5d (ACPI: Disable ASPM if the platform won't provide _OSC control for PCIe) control of the PCIe Capability Structure is unconditionally requested by acpi_pci_root_add(), which in principle may cause problems to happen in two ways. First, the BIOS may refuse to give control of the PCIe Capability Structure if it is not asked for any of the _OSC features depending on it at the same time. Second, the BIOS may assume that control of the _OSC features depending on the PCIe Capability Structure will be requested in the future and may behave incorrectly if that doesn't happen. For this reason, control of the PCIe Capability Structure should always be requested along with control of any other _OSC features that may depend on it (ie. PCIe native PME, PCIe native hot-plug, PCIe AER). Rework the PCIe port driver so that (1) it checks which native PCIe port services can be enabled, according to the BIOS, and (2) it requests control of all these services simultaneously. In particular, this causes pcie_portdrv_probe() to fail if the BIOS refuses to grant control of the PCIe Capability Structure, which means that no native PCIe port services can be enabled for the PCIe Root Complex the given port belongs to. If that happens, ASPM is disabled to avoid problems with mishandling it by the part of the PCIe hierarchy for which control of the PCIe Capability Structure has not been received. Make it possible to override this behavior using 'pcie_ports=native' (use the PCIe native services regardless of the BIOS response to the control request), or 'pcie_ports=compat' (do not use the PCIe native services at all). Accordingly, rework the existing PCIe port service drivers so that they don't request control of the services directly. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-08-22 04:02:38 +08:00
dev_dbg(&port->dev, "PCIe errors handled by BIOS.\n");
else
flags |= OSC_PCI_EXPRESS_AER_CONTROL;
}
status = acpi_pci_osc_control_set(handle, &flags,
OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
if (ACPI_FAILURE(status)) {
dev_dbg(&port->dev, "ACPI _OSC request failed (code %d)\n",
status);
return -ENODEV;
}
dev_info(&port->dev, "ACPI _OSC control granted for 0x%02x\n", flags);
*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;
}