kernel.git/drivers/acpi/pci_root.c, branch linux-3.6.y

Merge branches 'delete-gts-bfs', 'misc', 'novell-bugzilla-757888-numa' and 'osc-pcie' into base

2012-08-03T04:31:23Z

ACPI / PCI: Do not try to acquire _OSC control if that is hopeless

2012-07-31T01:15:07Z

If acpi_pci_osc_support() fails for the given flags, it doesn't make sense to call acpi_pci_osc_control_set() down the road for the same flags, because it will certainly fail too. Moreover, problem diagnostics is then harder, because it is not too easy to identify the reason of the _OSC failure in those cases. For this reason, check the status returned by acpi_pci_osc_support() for PCIe support flags and do not attempt to execute acpi_pci_osc_control_set() for those flags and print a message if it's "failure". For compatibility with the existing code, disable ASPM in that case too. Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown

PCI/ACPI: provide MMCONFIG address for PCI host bridges

2012-06-22T21:16:51Z

This patch provide MMCONFIG address for PCI host bridges, which will be used to support host bridge hotplug. It gets MMCONFIG address by evaluating _CBA method if available. Reviewed-by: Yinghai Lu Signed-off-by: Jiang Liu Signed-off-by: Bjorn Helgaas

PCI: Rework ASPM disable code

2011-12-05T18:21:45Z

Right now we forcibly clear ASPM state on all devices if the BIOS indicates that the feature isn't supported. Based on the Microsoft presentation "PCI Express In Depth for Windows Vista and Beyond", I'm starting to think that this may be an error. The implication is that unless the platform grants full control via _OSC, Windows will not touch any PCIe features - including ASPM. In that case clearing ASPM state would be an error unless the platform has granted us that control. This patch reworks the ASPM disabling code such that the actual clearing of state is triggered by a successful handoff of PCIe control to the OS. The general ASPM code undergoes some changes in order to ensure that the ability to clear the bits isn't overridden by ASPM having already been disabled. Further, this theoretically now allows for situations where only a subset of PCIe roots hand over control, leaving the others in the BIOS state. It's difficult to know for sure that this is the right thing to do - there's zero public documentation on the interaction between all of these components. But enough vendors enable ASPM on platforms and then set this bit that it seems likely that they're expecting the OS to leave them alone. Measured to save around 5W on an idle Thinkpad X220. Signed-off-by: Matthew Garrett Signed-off-by: Jesse Barnes

ACPI: fix 80 char overflow

2011-07-14T04:14:05Z

Trivial fix for 80 char line overflow in drivers/acpi/pci_root.c Signed-off-by: Jon Mason Signed-off-by: Len Brown

PCI/ACPI: Report _OSC control mask returned on failure to get control

2011-05-10T22:43:37Z

If an attempt to get _OSC control of the PCIe native features from the BIOS fails, report the resulting mask of control flags the BIOS was willing to grant in the error message. Moreover, if the _OSC support mask is insufficient for requesting control of the PCIe native features or pcie_ports_disabled is set, print a diagnostic message containing the _OSC support mask. This helps to diagnose obscure _OSC-related problems on a number machines. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes

PCI: Disable ASPM when _OSC control is not granted for PCIe services

2011-03-21T16:41:08Z

v3 -> v2: Added text to describe the problem v2 -> v1: Split this patch from v1 v1 : Part of: http://marc.info/?l=linux-pci&m=130042212003242&w=2 Disable ASPM when no _OSC control for PCIe services is granted by the BIOS. This is to protect systems with a buggy BIOS that did not set the ACPI FADT "ASPM Controls" bit even though the underlying HW can't do ASPM. To turn "on" ASPM the minimum the BIOS needs to do: 1. Clear the ACPI FADT "ASPM Controls" bit. 2. Support _OSC appropriately There is no _OSC Control bit for ASPM. However, we expect the BIOS to support _OSC for a Root Bridge that originates a PCIe hierarchy. If this is not the case - we are better off not enabling ASPM on that server. Commit 852972acff8f10f3a15679be2059bb94916cba5d (ACPI: Disable ASPM if the Platform won't provide _OSC control for PCIe) describes the above scenario. To quote verbatim from there: [The PCI SIG documentation for the _OSC OS/firmware handshaking interface states: "If the _OSC control method is absent from the scope of a host bridge device, then the operating system must not enable or attempt to use any features defined in this section for the hierarchy originated by the host bridge." The obvious interpretation of this is that the OS should not attempt to use PCIe hotplug, PME or AER - however, the specification also notes that an _OSC method is *required* for PCIe hierarchies, and experimental validation with An Alternative OS indicates that it doesn't use any PCIe functionality if the _OSC method is missing. That arguably means we shouldn't be using MSI or extended config space, but right now our problems seem to be limited to vendors being surprised when ASPM gets enabled on machines when other OSs refuse to do so. So, for now, let's just disable ASPM if the _OSC method doesn't exist or refuses to hand over PCIe capability control.] Signed-off-by: Naga Chumbalkar Cc: Rafael J. Wysocki Cc: Matthew Garrett Signed-off-by: Jesse Barnes

PCI/ACPI: Report ASPM support to BIOS if not disabled from command line

2011-03-21T16:38:02Z

We need to distinguish the situation in which ASPM support is disabled from the command line or through .config from the situation in which it is disabled, because the hardware or BIOS can't handle it. In the former case we should not report ASPM support to the BIOS through ACPI _OSC, but in the latter case we should do that. Introduce pcie_aspm_support_enabled() that can be used by acpi_pci_root_add() to determine whether or not it should report ASPM support to the BIOS through _OSC. Cc: stable@kernel.org References: https://bugzilla.kernel.org/show_bug.cgi?id=29722 References: https://bugzilla.kernel.org/show_bug.cgi?id=20232 Reported-and-tested-by: Ortwin Glück Reviewed-by: Kenji Kaneshige Tested-by: Kenji Kaneshige Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes

ACPI: Fix boot problem related to APEI with acpi_disabled set

2011-01-16T19:56:26Z

Commit 415e12b23792 ("PCI/ACPI: Request _OSC control once for each root bridge (v3)") put the acpi_hest_init() call in acpi_pci_root_init() into a wrong place, presumably because the author confused acpi_pci_disabled with acpi_disabled. Bring the code ordering in acpi_pci_root_init() back to sanity. Additionally, make sure that hest_disable is set when acpi_disabled is set, which is going to prevent acpi_hest_parse(), that still may be executed for acpi_disabled=1 through aer_acpi_firmware_first(), from crashing because of uninitialized hest_tab. Reported-and-tested-by: Andres Salomon Signed-off-by: Rafael J. Wysocki Signed-off-by: Linus Torvalds

PCI/ACPI: Request _OSC control once for each root bridge (v3)

2011-01-14T16:55:41Z

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 Tested-by: Ozan Caglayan Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes