[UPDATE PATCH V10 1/8] ACPI: I/O Remapping Table (IORT) initial support

Marc Zyngier marc.zyngier at arm.com
Mon Sep 12 06:04:29 PDT 2016


On 12/09/16 13:37, Tomasz Nowicki wrote:
> 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_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
>>>
>>> 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>
>>> Reviewed-by: Hanjun Guo <hanjun.guo at linaro.org>
>>> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi at 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.

May I convey a slight sense of urgency here? I'd like to cut the irqchip
branch for 4.9 pretty soon (this week), in order to let it sink in -next
for a few days at the very least.

It'd be a bit disappointing if these patches missed the boat this time
again.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...



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