Re: [Linaro-acpi] [PATCH V8 1/8] ACPI: I/O Remapping Table (IORT) initial support

From: Fu Wei
Date: Mon Sep 05 2016 - 11:31:56 EST


Hi Tomasz,

On 5 September 2016 at 14:12, Tomasz Nowicki <tn@xxxxxxxxxxxx> wrote:
> On 02.09.2016 13:52, Fu Wei wrote:
>>
>> Hi Tomasz,
>>
>> On 11 August 2016 at 18:06, Tomasz Nowicki <tn@xxxxxxxxxxxx> 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@xxxxxxxxxxxx>
>>> Reviewed-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
>>> ---
>>> drivers/acpi/Kconfig | 5 +
>>> drivers/acpi/Makefile | 2 +
>>> drivers/acpi/arm64/Kconfig | 6 ++
>>> drivers/acpi/arm64/Makefile | 1 +
>>> drivers/acpi/arm64/iort.c | 218
>>> ++++++++++++++++++++++++++++++++++++++++++++
>>> drivers/acpi/bus.c | 2 +
>>> include/linux/iort.h | 30 ++++++
>>> 7 files changed, 264 insertions(+)
>>> create mode 100644 drivers/acpi/arm64/Kconfig
>>> create mode 100644 drivers/acpi/arm64/Makefile
>>> create mode 100644 drivers/acpi/arm64/iort.c
>>> create mode 100644 include/linux/iort.h
>>>
>>> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
>>> index 445ce28..6cef2d1 100644
>>> --- a/drivers/acpi/Kconfig
>>> +++ b/drivers/acpi/Kconfig
>>> @@ -521,4 +521,9 @@ config ACPI_CONFIGFS
>>> userspace. The configurable ACPI groups will be visible under
>>> /config/acpi, assuming configfs is mounted under /config.
>>>
>>> +if ARM64
>>> +source "drivers/acpi/arm64/Kconfig"
>>> +
>>> +endif
>>> +
>>> endif # ACPI
>>> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
>>> index 5ae9d85..e5ada78 100644
>>> --- a/drivers/acpi/Makefile
>>> +++ b/drivers/acpi/Makefile
>>> @@ -105,3 +105,5 @@ obj-$(CONFIG_ACPI_CONFIGFS) += acpi_configfs.o
>>>
>>> video-objs += acpi_video.o video_detect.o
>>> obj-y += dptf/
>>> +
>>> +obj-$(CONFIG_ARM64) += arm64/
>>> diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig
>>> new file mode 100644
>>> index 0000000..fc818dc
>>> --- /dev/null
>>> +++ b/drivers/acpi/arm64/Kconfig
>>> @@ -0,0 +1,6 @@
>>> +#
>>> +# ACPI Configuration for ARM64
>>> +#
>>> +
>>> +config IORT_TABLE
>>
>>
>> Sorry for nit-picking, but is that better to use ACPI_IORT
>> or maybe ARM64__IORT ??
>
>
> ACPI_IORT sounds good.

Thanks, Tomasz :-)
I have rebaseed my GTDT patchset on your v8 patchset,
But before I post my new patchset, I hope we can harmonize with each
other on these:

1. ACPI_IORT -- ACPI_GTDT
2. for the file name, maybe can follow "/drivers/acpi/acpi_*.c" like
acpi_iort.c and acpi_gtdt.c
or follow "/drivers/acpi/apei/*.c" like iort.c and gtdt.c.

looking forward to you new patchset :-)
Thanks :-)

>
> Tomasz



--
Best regards,

Fu Wei
Software Engineer
Red Hat