Hi Rafael,
On 09.09.2016 11:20, Lorenzo Pieralisi wrote:
Hi Rafael,
On Wed, Sep 07, 2016 at 01:56:52PM +0200, 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_Remapp...
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
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@semihalf.com Reviewed-by: Hanjun Guo hanjun.guo@linaro.org Reviewed-by: Lorenzo Pieralisi lorenzo.pieralisi@arm.com
Apart from the minor commit logs oversights we consider these two patches ready to go, please let us know if there is something you want changed since we are at risk of missing yet another merge window.
It is ARM64 specific code, we created and moved the code to its ARM64 specific directory and we are happy to maintain it as such, we need your ACK to get this done so if there is something you want changed please let us know otherwise I would ask your ACK on these two patches to give Marc a go-ahead for -next and hopefully 4.9.
Kindly reminder. Is there anything we need to do more about these patches? Please let us know. Note this is the major thing for incoming IORT more advance feature.
Thanks, Tomasz