Eric Lee / smarc-fsl-linux-kernel

13 Sep, 2016

2 commits

  • 4bf2efd26   ACPI: Add new IORT functions to support MSI domain handling ... Browse Code »

    For ITS, MSI functionality consists on building domain stack and
    during that process we need to reference to domain stack components
    e.g. before we create new DOMAIN_BUS_PCI_MSI domain we need to specify
    its DOMAIN_BUS_NEXUS parent domain. In order to manage that process
    properly, maintain list which elements contain domain token
    (unique for MSI domain stack) and ITS ID: iort_register_domain_token()
    and iort_deregister_domain_token(). Then retrieve domain token
    any time later with ITS ID being key off: iort_find_domain_token().
    With domain token and domain type we are able to find corresponding
    IRQ domain.

    Since IORT is prepared to describe MSI domain on a per-device basis,
    use existing IORT helpers and implement two calls:
    1. iort_msi_map_rid() to map MSI RID for a device
    2. iort_get_device_domain() to find domain token for a device

    Signed-off-by: Tomasz Nowicki
    Acked-by: Rafael J. Wysocki
    Reviewed-by: Hanjun Guo
    Signed-off-by: Marc Zyngier

    Tomasz Nowicki
     
  • 88ef16d88   ACPI: I/O Remapping Table (IORT) initial support ... Browse Code »

    IORT shows representation of IO topology for ARM based systems.
    It describes how various components are connected together on
    parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec.
    http://infocenter.arm.com/help/topic/com.arm.doc.den0049b/DEN0049B_IO_Remapping_Table.pdf

    Initial support allows to detect IORT table presence and save its
    root pointer obtained through acpi_get_table(). The pointer validity
    depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap
    is not set while using IORT nodes we would dereference unmapped pointers.

    For the aforementioned reason call acpi_iort_init() from acpi_init()
    which guarantees acpi_gbl_permanent_mmap to be set at that point.

    Add generic helpers which are helpful for scanning and retrieving
    information from IORT table content. List of the most important helpers:
    - iort_find_dev_node() finds IORT node for a given device
    - iort_node_map_rid() maps device RID and returns IORT node which provides
    final translation

    IORT support is placed under drivers/acpi/arm64/ new directory due to its
    ARM64 specific nature. The code there is considered only for ARM64.
    The long term plan is to keep all ARM64 specific tables support
    in this place e.g. GTDT table.

    Signed-off-by: Tomasz Nowicki
    Acked-by: Rafael J. Wysocki
    Reviewed-by: Hanjun Guo
    Reviewed-by: Lorenzo Pieralisi
    Signed-off-by: Marc Zyngier

    Tomasz Nowicki