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

Christopher Covington cov at codeaurora.org
Tue Jul 26 06:19:15 PDT 2016


Hi Marc,

On 06/22/2016 09:34 PM, Hanjun Guo wrote:
> On 2016/6/22 22:51, Marc Zyngier wrote:
>> On 22/06/16 14:52, Tomasz Nowicki wrote:
>>> On 22.06.2016 15:25, Marc Zyngier wrote:
>>>> On 22/06/16 13:35, 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>
>>>>> ---
>>>>>   drivers/acpi/Kconfig  |   3 +
>>>>>   drivers/acpi/Makefile |   1 +
>>>>>   drivers/acpi/bus.c    |   2 +
>>>>>   drivers/acpi/iort.c   | 217 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>>>>   include/linux/iort.h  |  30 +++++++
>>>>>   5 files changed, 253 insertions(+)
>>>>>   create mode 100644 drivers/acpi/iort.c
>>>>>   create mode 100644 include/linux/iort.h

> I tracked Marc's tree on git.kernel.org, it's  acpi_os_free(buffer.pointer) there so
> my worry is gone :)

Do you plan on submitting this during the 4.8 merge window?

Thanks,
Cov

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