Overlays are a method to dynamically modify part of the kernel's
device tree with dynamically loaded data. Add the core functionality to
parse, apply and remove an overlay changeset. The core functionality
takes care of managing the overlay data format and performing the add
and remove. Drivers are expected to use the overlay functionality to
support custom expansion busses commonly found on consumer development
boards like the BeagleBone or Raspberry Pi.
The overlay code uses CONFIG_OF_DYNAMIC changesets to perform the low
level work of modifying the devicetree.
Documentation about internal and APIs is provided in
Documentation/devicetree/overlay-notes.txt
v2:
- Switch from __of_node_alloc() to __of_node_dup()
- Documentation fixups
- Remove 2-pass processing of properties
- Remove separate ov_lock; just use the DT mutex.
v1:
- Drop delete capability using '-' prefix. The '-' prefixed names
are valid properties and nodes and there is no need for it just yet.
- Do not update special properties - name & phandle ones.
- Change order of node attachment, so that the special property update
works.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Create a new /sys entry '/sys/firmware/fdt' to export the FDT blob
that was passed to the kernel by the bootloader. This allows userland
applications such as kexec to access the raw binary.
The fact that this node does not reside under /sys/firmware/device-tree
is deliberate: FDT is also used on arm64 UEFI/ACPI systems to
communicate just the UEFI and ACPI entry points, but the FDT is never
unflattened and used to configure the system.
A CRC32 checksum is calculated over the entire FDT blob, and verified
at late_initcall time. The sysfs entry is instantiated only if the
checksum is valid, i.e., if the FDT blob has not been modified in the
mean time. Otherwise, a warning is printed.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
This is unit testing code. It should use that name because it makes more
sense than 'selftest'. Rename the files to match and rename the config
variable.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
The selftest data ends up causing duplicate phandles in the live tree
for the time that the testcase data is inserted into the live tree. This
is obviously a bad situation because anything attempting to read the
tree while the selftests are running make resolve phandles to one of the
testcase data nodes. Fix the problem by using the of_resolve_phandles()
function to eliminate duplicates.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: Gaurav Minocha <gaurav.minocha.os@gmail.com>
Introduce support for dynamic device tree resolution.
Using it, it is possible to prepare a device tree that's
been loaded on runtime to be modified and inserted at the kernel
live tree.
Export of of_resolve and bug fix of double free by
Guenter Roeck <groeck@juniper.net>
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Don't need to select CONFIG_OF_DYNAMIC and CONFIG_OF_DEVICE]
[grant.likely: Don't need to depend on OF or !SPARC]
[grant.likely: Factor out duplicate code blocks into single function]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
This patch is to fix following error while compiling OF selftests.
"drivers/of/selftest.c:617:2: error: implicit declaration of function
'of_fdt_unflatten_tree'"
Now, CONFIG_OF_SELFTEST depends on CONFIG_OF_EARLY_FLATTREE so that the
broken configuration cannot be selected. Ultimately it would be a good
idea to allow CONFIG_OF_SELFTEST to select CONFIG_OF_EARLY_FLATTREE, but
there is a dependency problem on i386 and x86_64 that causes dtc to not
get built and causes the build to fail. That problem needs to be fixed
first.
Signed-off-by: Gaurav Minocha <gaurav.minocha.os@gmail.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
This patch attaches selftest's device tree data (required by /drivers/of/selftest.c)
dynamically into live device tree. First, it links selftest device tree data into the
kernel image and then iterates over all the nodes and attaches them into the live tree.
Once the testcases are complete, it removes the data attached.
This patch will remove the manual process of addition and removal of selftest device
tree data into the machine's dts file.
Tested successfully with current selftest's testcases.
Signed-off-by: Gaurav Minocha <gaurav.minocha.os@gmail.com>
[glikely: Removed ability to build as a module and fixed no-devicetree bug]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
The kernel FDT functions predate libfdt and are much more limited in
functionality. Also, the kernel functions and libfdt functions are
not compatible with each other because they have different definitions
of node offsets. To avoid this incompatibility and in preparation to
add more FDT parsing functions which will need libfdt, let's first
convert the existing code to use libfdt.
The FDT unflattening, top-level FDT scanning, and property retrieval
functions are converted to use libfdt. The scanning code should be
re-worked to be more efficient and understandable by using libfdt to
find nodes directly by path or compatible strings.
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
This patch adds support for dynamically allocated reserved memory regions
declared in device tree. Such regions are defined by 'size', 'alignment'
and 'alloc-ranges' properties.
Based on previous code provided by Josh Cartwright <joshc@codeaurora.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Translating an address from a PCI node of the device-tree into a CPU
physical address doesn't require the core PCI support. Those
translations are just related to the device tree itself.
The use case to translate an address from a PCI node without actually
using the PCI core support is when one needs to access the PCI
controller without accessing any PCI devices.
Marvell SoCs, such as Kirkwood, Dove or Armada XP for instance, come
with an IP of a PCI controller. In the registers of this controller
are stored the ID and the revision of a SoC. With this patch it will
be possible to read the SoC ID of a board without any PCI device and
then without the PCI core support.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Reviewed-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Pull devicetree updates from Rob Herring:
"DeviceTree updates for 3.13. This is a bit larger pull request than
usual for this cycle with lots of clean-up.
- Cross arch clean-up and consolidation of early DT scanning code.
- Clean-up and removal of arch prom.h headers. Makes arch specific
prom.h optional on all but Sparc.
- Addition of interrupts-extended property for devices connected to
multiple interrupt controllers.
- Refactoring of DT interrupt parsing code in preparation for
deferred probe of interrupts.
- ARM cpu and cpu topology bindings documentation.
- Various DT vendor binding documentation updates"
* tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (82 commits)
powerpc: add missing explicit OF includes for ppc
dt/irq: add empty of_irq_count for !OF_IRQ
dt: disable self-tests for !OF_IRQ
of: irq: Fix interrupt-map entry matching
MIPS: Netlogic: replace early_init_devtree() call
of: Add Panasonic Corporation vendor prefix
of: Add Chunghwa Picture Tubes Ltd. vendor prefix
of: Add AU Optronics Corporation vendor prefix
of/irq: Fix potential buffer overflow
of/irq: Fix bug in interrupt parsing refactor.
of: set dma_mask to point to coherent_dma_mask
of: add vendor prefix for PHYTEC Messtechnik GmbH
DT: sort vendor-prefixes.txt
of: Add vendor prefix for Cadence
of: Add empty for_each_available_child_of_node() macro definition
arm/versatile: Fix versatile irq specifications.
of/irq: create interrupts-extended property
microblaze/pci: Drop PowerPC-ism from irq parsing
of/irq: Create of_irq_parse_and_map_pci() to consolidate arch code.
of/irq: Use irq_of_parse_and_map()
...
Fix OF selftest compile on sparc which does not enable OF_IRQ.
drivers/of/selftest.c:177: undefined reference to `of_irq_parse_one'
drivers/of/selftest.c:197: undefined reference to `of_irq_parse_one'
drivers/of/selftest.c:248: undefined reference to `of_irq_parse_one'
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
This reverts commit 9d8eab7af7. There is
still no consensus on the bindings for the reserved memory and various
drawbacks of the proposed solution has been shown, so the best now is to
revert it completely and start again from scratch later.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Pull DMA mapping update from Marek Szyprowski:
"This contains an addition of Device Tree support for reserved memory
regions (Contiguous Memory Allocator is one of the drivers for it) and
changes required by the KVM extensions for PowerPC architectue"
* 'for-v3.12' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
ARM: init: add support for reserved memory defined by device tree
drivers: of: add initialization code for dma reserved memory
drivers: of: add function to scan fdt nodes given by path
drivers: dma-contiguous: clean source code and prepare for device tree
This patch adds device tree support for contiguous and reserved memory
regions defined in device tree.
Large memory blocks can be reliably reserved only during early boot.
This must happen before the whole memory management subsystem is
initialized, because we need to ensure that the given contiguous blocks
are not yet allocated by kernel. Also it must happen before kernel
mappings for the whole low memory are created, to ensure that there will
be no mappings (for reserved blocks) or mapping with special properties
can be created (for CMA blocks). This all happens before device tree
structures are unflattened, so we need to get reserved memory layout
directly from fdt.
Later, those reserved memory regions are assigned to devices on each
device structure initialization.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Rob Herring <rob.herring@calxeda.com>
I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
CONFIG_OF_DEVICE is always selected when CONFIG_OF is enabled, so remove
it and simplify of_platform.h and of_device.h headers. This also fixes
!OF compiles using of_platform_populate.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Pull GPIO driver changes from Grant Likely:
"Lots of gpio changes, both to core code and drivers.
Changes do touch architecture code to remove the need for separate
arm/gpio.h includes in most architectures.
Some new drivers are added, and a number of gpio drivers are converted
to use irq_domains for gpio inputs used as interrupts. Device tree
support has been amended to allow multiple gpio_chips to use the same
device tree node.
Remaining changes are primarily bug fixes."
* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6: (33 commits)
gpio/generic: initialize basic_mmio_gpio shadow variables properly
gpiolib: Remove 'const' from data argument of gpiochip_find()
gpio/rc5t583: add gpio driver for RICOH PMIC RC5T583
gpiolib: quiet gpiochip_add boot message noise
gpio: mpc8xxx: Prevent NULL pointer deref in demux handler
gpio/lpc32xx: Add device tree support
gpio: Adjust of_xlate API to support multiple GPIO chips
gpiolib: Implement devm_gpio_request_one()
gpio-mcp23s08: dbg_show: fix pullup configuration display
Add support for TCA6424A
gpio/omap: (re)fix wakeups on level-triggered GPIOs
gpio/omap: fix broken context restore for non-OFF mode transitions
gpio/omap: fix missing check in *_runtime_suspend()
gpio/omap: remove cpu_is_omapxxxx() checks from *_runtime_resume()
gpio/omap: remove suspend/resume callbacks
gpio/omap: remove retrigger variable in gpio_irq_handler
gpio/omap: remove saved_wakeup field from struct gpio_bank
gpio/omap: remove suspend_wakeup field from struct gpio_bank
gpio/omap: remove saved_fallingdetect, saved_risingdetect
gpio/omap: remove virtual_irq_start variable
...
Conflicts:
drivers/gpio/gpio-samsung.c
The SPI device tree support code isn't shared by any other subsystem. It can
be moved into the core drivers/spi directory and the exported symbol can be
removed.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
The code in drivers/of/gpio.c isn't shared by any other subsystem since it
is all gpiolib specific. drivers/gpio is a better place to maintain these
functions.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Grant Likely
Pantelis Antoniou
Ard Biesheuvel
Gaurav Minocha
Rob Herring
Grant Likely
Marek Szyprowski
Gregory CLEMENT
Geert Uytterhoeven
Linus Torvalds
Rob Herring
Wolfram Sang
Andreas Larsson