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

[Tomasz Nowicki]

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.

Tomasz