From 88ef16d888a094587b2ac77de60927df5da5d56d Mon Sep 17 00:00:00 2001 From: Tomasz Nowicki Date: Mon, 12 Sep 2016 20:54:20 +0200 Subject: ACPI: I/O Remapping Table (IORT) initial support 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 --- drivers/acpi/arm64/Kconfig | 6 ++++++ 1 file changed, 6 insertions(+) create mode 100644 drivers/acpi/arm64/Kconfig (limited to 'drivers/acpi/arm64/Kconfig') diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig new file mode 100644 index 000000000000..4616da4c15be --- /dev/null +++ b/drivers/acpi/arm64/Kconfig @@ -0,0 +1,6 @@ +# +# ACPI Configuration for ARM64 +# + +config ACPI_IORT + bool -- cgit v1.2.3-59-g8ed1b