[UPDATE PATCH V11 1/8] ACPI: I/O Remapping Table (IORT) initial support

Tomasz Nowicki tn at semihalf.com
Mon Sep 12 11:58:42 PDT 2016


On 12.09.2016 20:54, 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 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 <tn at semihalf.com>
> Acked-by: Rafael J. Wysocki <rjw at rjwysocki.net>
> Reviewed-by: Hanjun Guo <hanjun.guo at linaro.org>
> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>

Hi Marc,

Series with updated patch 1 can be found:
https://github.com/semihalf-nowicki-tomasz/linux.git (its-acpi-v11)

Sorry for zillions of patch updates...

Thanks,
Tomasz




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