[PATCH V7 1/8] ACPI: I/O Remapping Table (IORT) initial support

Tomasz Nowicki tn at semihalf.com
Wed Jun 22 05:40:28 PDT 2016


On 22.06.2016 14:35, Tomasz Nowicki wrote:
> 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 iort_table_detect() 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
>
> Signed-off-by: Tomasz Nowicki <tn at semihalf.com>

The updated patch incorporates fixes and addresses Lorenzo's comments.
The whole series is here:
https://github.com/semihalf-nowicki-tomasz/linux.git (its-acpi-v7.1)

Thanks,
Tomasz



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