The Amlogic G12A has a slighly different Power Control, but uses the
same address space and sysctrl registers.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
The Amlogic Meson GXM SoC embeds an ARM Mali T820 GPU.
This patch adds the node with all the needed properties to power
on the GPU.
This has been tested with the work-in-progress PanFrost project
aiming support for ARM Mali Midgard and later GPUs.
Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
The Amlogic ARM Mali Midgard requires reset controls to power on and
software reset the GPU, adds these as optional in the bindings.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Export the four video decoder clocks so they can be used by the video
decoder driver:
- VDEC_1
- VDEC_HCODEC
- VDEC_2
- VDEC_HEVC
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190324151423.19063-2-martin.blumenstingl@googlemail.com
The VPU clock is an input the the "VPU" (Video Processing Unit), which is
one of the components of the display controller.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190324151104.18397-2-martin.blumenstingl@googlemail.com
When submitted v2 of the G12A AO-CLK IDs, the CLKID_AO_CTS_OSCIN was moved
to the internal non-exported bindings, but this clock is necessary for
the second AO-CEC-B module since it embeds the 32768Hz dual-divider
clock generator unlike the AO-CEC-A module.
Export it back to the public bindings.
Fixes: be3d960b0a ("dt-bindings: clk: add G12A AO Clock and Reset Bindings")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lkml.kernel.org/r/20190321092010.14382-1-narmstrong@baylibre.com
Commit 8e1dd17c8b ("dt-bindings: clock: meson8b: export the CPU post
dividers") added a new clock ID "CLKID_ABP" which contains a typo. This
was fixed by adding a new (typo-free) #define CLKID_APB in
commit 40d08f774c ("dt-bindings: clock: meson8b: add APB clock
definition").
Now that the new #define is used by the driver we can remove the old
one (because the old one is not used anywhere).
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190319214123.27219-2-martin.blumenstingl@googlemail.com
Expose the three clocks related to the video decoder.
Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190319101138.27520-2-mjourdan@baylibre.com
Remove the bindings ID of the clock input of the controller. These
clocks are purely internal to the controller, exposing them was a
mistake. Actually, these should not even be in the provider and have
IDs to begin with.
Unexpose these IDs before:
* someone starts using them (even if there no valid reason to do so)
* the actual clocks are removed. The fact that they exist is just the
result of an ugly hack. This will be resolved in CCF when we can
reference DT directly in parent table.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Maxime Jourdan <mjourdan@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190213095835.17448-1-jbrunet@baylibre.com
In order to handle Video Output and later on Video decoding,
add a reserved CMA pool with a similar 256MiB size as other SoCs.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Enable the Bluetooth Module on the X96 Max Set-Top-Box.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Add system regulators for the X96 Max Set-Top-Box.
Still missing
* VDD_EE (0.8V - PWM controlled)
* VDD_CPU (PWM controlled)
Signed-off-by: Guillaume La Roque <glaroque@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
The G12A Documentation lacked these 2 reset lines, but they are present and
used for each USB 2 PHYs.
Add them to the dt-bindings for the upcoming USB support.
Fixes: dbfc54534d ("dt-bindings: reset: meson: add g12a bindings")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Add pinctrl on the always-enabled debug UART AO.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Add pinctrl on the always-enabled debug UART AO.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Add pinctrl on the always-enabled debug UART AO.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
This patch adds the 3 UART nodes in the EE power domain with the corresponding
pinctrl nodes.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Add the reset controller device of g12a SoC family
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Add the always on UART pinctrl setting to the g12a soc DT.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Add the peripheral and always-on pinctrl controllers to the g12a soc.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Add nodes and properties for the AO Clocks and Resets.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
When submitted v2 of the G12A AO-CLK IDs, the SAR_ADC_SEL ID was moved
to the internal non-exported bindings, but this clock is necessary and
mandatory for the SAR ADC bindings.
Export it back to the public bindings.
Fixes: be3d960b0a ("dt-bindings: clk: add G12A AO Clock and Reset Bindings")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lkml.kernel.org/r/20190304105358.4987-1-narmstrong@baylibre.com
Add Amlogic G12A Family CPU clocks bindings, only export CPU_CLK since
it should be the only ID used.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lkml.kernel.org/r/20190304131129.7762-2-narmstrong@baylibre.com
There is a white LED on the front panel behind the logo and the
manufacturer uses that LED to indicate network and USB drive status.
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
This adds the Always-On ao-secure system control registers node,
which is used by the meson-gx-socinfo driver to detect the SoC IDs.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
The SEI Robotics SEI510 Board is based on the Amlogic G12A S905X2
and has the following features :
- Amlogic G12A S905X2 SoC
- 10/100 Ethernet
- USB2 + USB3 ports
- Micro SDCard Port
- Audio + CVBS AV Jack port
- HDMI 2.1 + CEC Port
- ADC Touch Button
- Far-Field Microphone Array + Mono HP
- IR Sensor
- IR Emmiter LED Array
- RGB Led
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[khilman: sorted Makefile entry alphabetcially]
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Add vendor prefix for the Shenzhen SEI Robotics Co., Ltd, a chinese ODM
specialized in Android TV HDMI Stick, OTT Box, Hybrid STB,
Smart Home Gateway & more.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Pull x86 asm updates from Thomas Gleixner:
"Two cleanup patches removing dead conditionals and unused code"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm: Remove unused __constant_c_x_memset() macro and inlines
x86/asm: Remove dead __GNUC__ conditionals
Pull perf fixes from Thomas Gleixner:
"Three fixes for the fallout from the TSX errata workaround:
- Prevent memory corruption caused by a unchecked out of bound array
index.
- Two trivial fixes to address compiler warnings"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Make dev_attr_allow_tsx_force_abort static
perf/x86: Fixup typo in stub functions
perf/x86/intel: Fix memory corruption
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCXI36jAAKCRCAXGG7T9hj
vmL1AQC/kDMDp7qHr9hxf+xsEvkQWRU/DENwnoPBI9WtfiVjWQEAuXcZ5pd8H2Iw
d7yFo1c2h14jVnnRhDhQ2wAS1aPT0gY=
=fkTe
-----END PGP SIGNATURE-----
Merge tag 'for-linus-5.1b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fix from Juergen Gross:
"A fix for a Xen bug introduced by David's series for excluding
ballooned pages in vmcores"
* tag 'for-linus-5.1b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/balloon: Fix mapping PG_offline pages to user space
Two fixes (leak on invalid mount argument and possible deadlock on
i_size update on 32bit smp) and a fall-through warning cleanup
----------------------------------------------------------------
Gustavo A. R. Silva (1):
9p: mark expected switch fall-through
Hou Tao (1):
9p: use inode->i_lock to protect i_size_write() under 32-bit
zhengbin (1):
9p/net: fix memory leak in p9_client_create
fs/9p/v9fs_vfs.h | 23 +++++++++++++++++++++--
fs/9p/vfs_file.c | 6 +++++-
fs/9p/vfs_inode.c | 23 +++++++++++------------
fs/9p/vfs_inode_dotl.c | 27 ++++++++++++++-------------
fs/9p/vfs_super.c | 4 ++--
net/9p/client.c | 2 +-
net/9p/trans_xen.c | 2 +-
7 files changed, 55 insertions(+), 32 deletions(-)
-----BEGIN PGP SIGNATURE-----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=q3cR
-----END PGP SIGNATURE-----
Merge tag '9p-for-5.1' of git://github.com/martinetd/linux
Pull 9p updates from Dominique Martinet:
"Here is a 9p update for 5.1; there honestly hasn't been much.
Two fixes (leak on invalid mount argument and possible deadlock on
i_size update on 32bit smp) and a fall-through warning cleanup"
* tag '9p-for-5.1' of git://github.com/martinetd/linux:
9p/net: fix memory leak in p9_client_create
9p: use inode->i_lock to protect i_size_write() under 32-bit
9p: mark expected switch fall-through
When this .gitignore was added, lxdialog was an independent hostprogs-y.
Now that all objects in lxdialog/ are directly linked to mconf, the
lxdialog is no longer generated.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently, every arch/*/include/uapi/asm/Kbuild explicitly includes
the common Kbuild.asm file. Factor out the duplicated include directives
to scripts/Makefile.asm-generic so that no architecture would opt out
of the mandatory-y mechanism.
um is not forced to include mandatory-y since it is a very exceptional
case which does not support UAPI.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The generic-y is redundant under the following condition:
- arch has its own implementation
- the same header is added to generated-y
- the same header is added to mandatory-y
If a redundant generic-y is found, the warning like follows is displayed:
scripts/Makefile.asm-generic:20: redundant generic-y found in arch/arm/include/asm/Kbuild: timex.h
I fixed up arch Kbuild files found by this.
Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
During a simple no-op (nothing changed) build I saw 39 invocations of
the C compiler with the argument "-print-file-name=include". We don't
need to call the C compiler 39 times for this--one time will suffice.
Let's change NOSTDINC_FLAGS to a simply expanded variable to avoid
this since there doesn't appear to be any reason it should be
recursively expanded.
On my build this shaved ~400 ms off my "no-op" build.
Note that the recursive expansion seems to date back to the (really
old) commit e8f5bdb02c ("[PATCH] Makefile include path ordering").
It's a little unclear to me if the point of that patch was to switch
the variable to be recursively expanded (which it did) or to avoid
directly assigning to NOSTDINC_FLAGS (AKA to switch to +=) because
someone else (out of tree?) was setting it. I presume later since if
the only goal was to switch to recursive expansion the patch would
have just removed the ":".
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
* The man page for dpkg-source(1) notes:
> -b, --build directory [format-specific-parameters]
> Build a source package (--build since dpkg 1.17.14).
> <...>
>
> dpkg-source will build the source package with the first
> format found in this ordered list: the format indicated
> with the --format command line option, the format
> indicated in debian/source/format, “1.0”. The fallback
> to “1.0” is deprecated and will be removed at some point
> in the future, you should always document the desired
> source format in debian/source/format. See section
> SOURCE PACKAGE FORMATS for an extensive description of
> the various source package formats.
Thus it would be more foolproof to explicitly use 1.0 (as we always
did) than to rely on dpkg-source's defaults.
* In a similar vein, debian/rules is not made executable by mkdebian,
and dpkg-source warns about that but still silently fixes the file.
Let's be explicit once again.
Signed-off-by: Arseny Maslennikov <ar@cs.msu.ru>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The of_find_device_by_node() takes a reference to the underlying device
structure, we should release that reference.
The implementation of this semantic code search is:
In a function, for a local variable returned by calling
of_find_device_by_node(),
a, if it is released by a function such as
put_device()/of_dev_put()/platform_device_put() after the last use,
it is considered that there is no reference leak;
b, if it is passed back to the caller via
dev_get_drvdata()/platform_get_drvdata()/get_device(), etc., the
reference will be released in other functions, and the current function
also considers that there is no reference leak;
c, for the rest of the situation, the current function should release the
reference by calling put_device, this code search will report the
corresponding error message.
By using this semantic code search, we have found some object reference leaks,
such as:
commit 11907e9d35 ("ASoC: fsl-asoc-card: fix object reference leaks in
fsl_asoc_card_probe")
commit a12085d139 ("mtd: rawnand: atmel: fix possible object reference leak")
commit 11493f2685 ("mtd: rawnand: jz4780: fix possible object reference leak")
There are still dozens of reference leaks in the current kernel code.
Further, for the case of b, the object returned to other functions may also
have a reference leak, we will continue to develop other cocci scripts to
further check the reference leak.
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Reviewed-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Markus Elfring <Markus.Elfring@web.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
-----BEGIN PGP SIGNATURE-----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=yOWp
-----END PGP SIGNATURE-----
Merge tag 'pidfd-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd system call from Christian Brauner:
"This introduces the ability to use file descriptors from /proc/<pid>/
as stable handles on struct pid. Even if a pid is recycled the handle
will not change. For a start these fds can be used to send signals to
the processes they refer to.
With the ability to use /proc/<pid> fds as stable handles on struct
pid we can fix a long-standing issue where after a process has exited
its pid can be reused by another process. If a caller sends a signal
to a reused pid it will end up signaling the wrong process.
With this patchset we enable a variety of use cases. One obvious
example is that we can now safely delegate an important part of
process management - sending signals - to processes other than the
parent of a given process by sending file descriptors around via scm
rights and not fearing that the given process will have been recycled
in the meantime. It also allows for easy testing whether a given
process is still alive or not by sending signal 0 to a pidfd which is
quite handy.
There has been some interest in this feature e.g. from systems
management (systemd, glibc) and container managers. I have requested
and gotten comments from glibc to make sure that this syscall is
suitable for their needs as well. In the future I expect it to take on
most other pid-based signal syscalls. But such features are left for
the future once they are needed.
This has been sitting in linux-next for quite a while and has not
caused any issues. It comes with selftests which verify basic
functionality and also test that a recycled pid cannot be signaled via
a pidfd.
Jon has written about a prior version of this patchset. It should
cover the basic functionality since not a lot has changed since then:
https://lwn.net/Articles/773459/
The commit message for the syscall itself is extensively documenting
the syscall, including it's functionality and extensibility"
* tag 'pidfd-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
selftests: add tests for pidfd_send_signal()
signal: add pidfd_send_signal() syscall
* Replace the /sys/class/dax device model with /sys/bus/dax, and include
a compat driver so distributions can opt-in to the new ABI.
* Allow for an alternative driver for the device-dax address-range
* Introduce the 'kmem' driver to hotplug / assign a device-dax
address-range to the core-mm.
* Arrange for the device-dax target-node to be onlined so that the newly
added memory range can be uniquely referenced by numa apis.
-----BEGIN PGP SIGNATURE-----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=hfa3
-----END PGP SIGNATURE-----
Merge tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull device-dax updates from Dan Williams:
"New device-dax infrastructure to allow persistent memory and other
"reserved" / performance differentiated memories, to be assigned to
the core-mm as "System RAM".
Some users want to use persistent memory as additional volatile
memory. They are willing to cope with potential performance
differences, for example between DRAM and 3D Xpoint, and want to use
typical Linux memory management apis rather than a userspace memory
allocator layered over an mmap() of a dax file. The administration
model is to decide how much Persistent Memory (pmem) to use as System
RAM, create a device-dax-mode namespace of that size, and then assign
it to the core-mm. The rationale for device-dax is that it is a
generic memory-mapping driver that can be layered over any "special
purpose" memory, not just pmem. On subsequent boots udev rules can be
used to restore the memory assignment.
One implication of using pmem as RAM is that mlock() no longer keeps
data off persistent media. For this reason it is recommended to enable
NVDIMM Security (previously merged for 5.0) to encrypt pmem contents
at rest. We considered making this recommendation an actively enforced
requirement, but in the end decided to leave it as a distribution /
administrator policy to allow for emulation and test environments that
lack security capable NVDIMMs.
Summary:
- Replace the /sys/class/dax device model with /sys/bus/dax, and
include a compat driver so distributions can opt-in to the new ABI.
- Allow for an alternative driver for the device-dax address-range
- Introduce the 'kmem' driver to hotplug / assign a device-dax
address-range to the core-mm.
- Arrange for the device-dax target-node to be onlined so that the
newly added memory range can be uniquely referenced by numa apis"
NOTE! I'm not entirely happy with the whole "PMEM as RAM" model because
we currently have special - and very annoying rules in the kernel about
accessing PMEM only with the "MC safe" accessors, because machine checks
inside the regular repeat string copy functions can be fatal in some
(not described) circumstances.
And apparently the PMEM modules can cause that a lot more than regular
RAM. The argument is that this happens because PMEM doesn't necessarily
get scrubbed at boot like RAM does, but that is planned to be added for
the user space tooling.
Quoting Dan from another email:
"The exposure can be reduced in the volatile-RAM case by scanning for
and clearing errors before it is onlined as RAM. The userspace tooling
for that can be in place before v5.1-final. There's also runtime
notifications of errors via acpi_nfit_uc_error_notify() from
background scrubbers on the DIMM devices. With that mechanism the
kernel could proactively clear newly discovered poison in the volatile
case, but that would be additional development more suitable for v5.2.
I understand the concern, and the need to highlight this issue by
tapping the brakes on feature development, but I don't see PMEM as RAM
making the situation worse when the exposure is also there via DAX in
the PMEM case. Volatile-RAM is arguably a safer use case since it's
possible to repair pages where the persistent case needs active
application coordination"
* tag 'devdax-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
device-dax: "Hotplug" persistent memory for use like normal RAM
mm/resource: Let walk_system_ram_range() search child resources
mm/memory-hotplug: Allow memory resources to be children
mm/resource: Move HMM pr_debug() deeper into resource code
mm/resource: Return real error codes from walk failures
device-dax: Add a 'modalias' attribute to DAX 'bus' devices
device-dax: Add a 'target_node' attribute
device-dax: Auto-bind device after successful new_id
acpi/nfit, device-dax: Identify differentiated memory with a unique numa-node
device-dax: Add /sys/class/dax backwards compatibility
device-dax: Add support for a dax override driver
device-dax: Move resource pinning+mapping into the common driver
device-dax: Introduce bus + driver model
device-dax: Start defining a dax bus model
device-dax: Remove multi-resource infrastructure
device-dax: Kill dax_region base
device-dax: Kill dax_region ida