Create a cache of the nodes that contain a phandle property. Use this
cache to find the node for a given phandle value instead of scanning
the devicetree to find the node. If the phandle value is not found
in the cache, of_find_node_by_phandle() will fall back to the tree
scan algorithm.
The cache is initialized in of_core_init().
The cache is freed via a late_initcall_sync() if modules are not
enabled.
If the devicetree is created by the dtc compiler, with all phandle
property values auto generated, then the size required by the cache
could be 4 * (1 + number of phandles) bytes. This results in an O(1)
node lookup cost for a given phandle value. Due to a concern that the
phandle property values might not be consistent with what is generated
by the dtc compiler, a mask has been added to the cache lookup algorithm.
To maintain the O(1) node lookup cost, the size of the cache has been
increased by rounding the number of entries up to the next power of
two.
The overhead of finding the devicetree node containing a given phandle
value has been noted by several people in the recent past, in some cases
with a patch to add a hashed index of devicetree nodes, based on the
phandle value of the node. One concern with this approach is the extra
space added to each node. This patch takes advantage of the phandle
property values auto generated by the dtc compiler, which begin with
one and monotonically increase by one, resulting in a range of 1..n
for n phandle values. This implementation should also provide a good
reduction of overhead for any range of phandle values that are mostly
in a monotonic range.
Performance measurements by Chintan Pandya <cpandya@codeaurora.org>
of several implementations of patches that are similar to this one
suggest an expected reduction of boot time by ~400ms for his test
system. If the cache size was decreased to 64 entries, the boot
time was reduced by ~340 ms. The measurements were on a 4.9.73 kernel
for arch/arm64/boot/dts/qcom/sda670-mtp.dts, contains 2371 nodes and
814 phandle values.
Reported-by: Chintan Pandya <cpandya@codeaurora.org>
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Platforms like 96boards have a standardized connector/expansion
slot that exposes signals like GPIOs to expansion boards in an
SoC agnostic way. We'd like the DT overlays for the expansion
boards to be written once without knowledge of the SoC on the
other side of the connector. This avoids the unscalable
combinatorial explosion of a different DT overlay for each
expansion board and SoC pair.
We need a way to describe the GPIOs routed through the connector
in an SoC agnostic way. Let's introduce nexus property parsing
into the OF core to do this. This is largely based on the
interrupt nexus support we already have. This allows us to remap
a phandle list in a consumer node (e.g. reset-gpios) through a
connector in a generic way (e.g. via gpio-map). Do this in a
generic routine so that we can remap any sort of variable length
phandle list.
Taking GPIOs as an example, the connector would be a GPIO nexus,
supporting the remapping of a GPIO specifier space to multiple
GPIO providers on the SoC. DT would look as shown below, where
'soc_gpio1' and 'soc_gpio2' are inside the SoC, 'connector' is an
expansion port where boards can be plugged in, and
'expansion_device' is a device on the expansion board.
soc {
soc_gpio1: gpio-controller1 {
#gpio-cells = <2>;
};
soc_gpio2: gpio-controller2 {
#gpio-cells = <2>;
};
};
connector: connector {
#gpio-cells = <2>;
gpio-map = <0 0 &soc_gpio1 1 0>,
<1 0 &soc_gpio2 4 0>,
<2 0 &soc_gpio1 3 0>,
<3 0 &soc_gpio2 2 0>;
gpio-map-mask = <0xf 0x0>;
gpio-map-pass-thru = <0x0 0x1>
};
expansion_device {
reset-gpios = <&connector 2 GPIO_ACTIVE_LOW>;
};
The GPIO core would use of_parse_phandle_with_args_map() instead
of of_parse_phandle_with_args() and arrive at the same type of
result, a phandle and argument list. The difference is that the
phandle and arguments will be remapped through the nexus node to
the underlying SoC GPIO controller node. In the example above,
we would remap 'reset-gpios' from <&connector 2 GPIO_ACTIVE_LOW>
to <&soc_gpio1 3 GPIO_ACTIVE_LOW>.
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Pull DeviceTree updates from Rob Herring:
- Convert to use memblock_virt_alloc in DT code which supports
bootmem arches. With this we can remove the arch specific
early_init_dt_alloc_memory_arch() functions.
- Enable running the DT unittests on UML
- Use SPDX license tags on DT files
- Fix early FDT kconfig ifdef logic
- Clean-up unittest Makefile
- Fix function comment for of_irq_parse_raw
- Add missing documentation for linux,initrd-{start,end} properties
- Clean-up of binding examples using uppercase hex
- Add trivial devices W83773G and Infineon TLV493D-A1B6
- Add missing STM32 SoC bindings
- Various small binding doc fixes
* tag 'devicetree-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (23 commits)
xtensa: remove arch specific early DT functions
x86: remove arch specific early_init_dt_alloc_memory_arch
nios2: remove arch specific early_init_dt_alloc_memory_arch
mips: remove arch specific early_init_dt_alloc_memory_arch
metag: remove arch specific early DT functions
cris: remove arch specific early DT functions
libfdt: remove unnecessary include directive from <linux/libfdt.h>
of: unittest: refactor Makefile
of/fdt: use memblock_virt_alloc for early alloc
of: Use SPDX license tag for DT files
of/fdt: Fix #ifdef dependency of early flattree declarations
dt-bindings: h8300 clocksource: correct spelling of pulse
dt-bindings: imx6q-pcie: Add required property for i.MX6SX
mmc: Don't reference Linux-specific OF_GPIO_ACTIVE_LOW flag in DT binding
dt-bindings: Use lower case hex in unit-addresses
dt-bindings: display: panel: Fix compatible string for Toshiba LT089AC29000
dt-bindings: Add Infineon TLV493D-A1B6
dt-bindings: mailbox: ti,message-manager: Fix interrupt name error
dt-bindings: chosen: Document linux,initrd-{start,end}
dt-bindings: arm: document supported STM32 SoC family
...
Add a helper to map a device node to a logical CPU number to avoid
duplication. Currently this is open coded in different places (e.g
gic-v3, coresight). The helper tries to map device node to a "possible"
logical CPU id, which may not be online yet. It is the responsibility
of the user to make sure that the CPU is online. The helper uses
of_cpu_device_node_get() to retrieve the device node for a given CPU
(which uses per_cpu data if available else falls back to slower
of_get_cpu_node()).
Cc: devicetree@vger.kernel.org
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
It isn't clear if this function of_node_put()s the 'from'
argument, or the node it searches. Clearly indicate which
variable is touched. Fold in some more fixes from Randy too
because we're in the area.
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Pull DeviceTree updates from Rob Herring:
"A bigger diffstat than usual with the kbuild changes and a tree wide
fix in the binding documentation.
Summary:
- kbuild cleanups and improvements for dtbs
- Code clean-up of overlay code and fixing for some long standing
memory leak and race condition in applying overlays
- Improvements to DT memory usage making sysfs/kobjects optional and
skipping unflattening of disabled nodes. This is part of kernel
tinification efforts.
- Final piece of removing storing the full path for every DT node.
The prerequisite conversion of printk's to use device_node format
specifier happened in 4.14.
- Sync with current upstream dtc. This brings additional checks to
dtb compiling.
- Binding doc tree wide removal of leading 0s from examples
- RTC binding documentation adding missing devices and some
consolidation of duplicated bindings
- Vendor prefix documentation for nutsboard, Silicon Storage
Technology, shimafuji, Tecon Microprocessor Technologies, DH
electronics GmbH, Opal Kelly, and Next Thing"
* tag 'devicetree-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (55 commits)
dt-bindings: usb: add #phy-cells to usb-nop-xceiv
dt-bindings: Remove leading zeros from bindings notation
kbuild: handle dtb-y and CONFIG_OF_ALL_DTBS natively in Makefile.lib
MIPS: dts: remove bogus bcm96358nb4ser.dtb from dtb-y entry
kbuild: clean up *.dtb and *.dtb.S patterns from top-level Makefile
.gitignore: move *.dtb and *.dtb.S patterns to the top-level .gitignore
.gitignore: sort normal pattern rules alphabetically
dt-bindings: add vendor prefix for Next Thing Co.
scripts/dtc: Update to upstream version v1.4.5-6-gc1e55a5513e9
of: dynamic: fix memory leak related to properties of __of_node_dup
of: overlay: make pr_err() string unique
of: overlay: pr_err from return NOTIFY_OK to overlay apply/remove
of: overlay: remove unneeded check for NULL kbasename()
of: overlay: remove a dependency on device node full_name
of: overlay: simplify applying symbols from an overlay
of: overlay: avoid race condition between applying multiple overlays
of: overlay: loosen overly strict phandle clash check
of: overlay: expand check of whether overlay changeset can be removed
of: overlay: detect cases where device tree may become corrupt
of: overlay: minor restructuring
...
The "%pOF" printf format was recently added to print the
full name of a device tree node, with the intent of changing
the node full_name field to contain only the node name instead
of the full path of the node.
dup_and_fixup_symbol_prop() duplicates a property from the
"/__symbols__" node of an overlay device tree. The value
of each duplicated property must be fixed up to include
the full path of a node in the live device tree. The
current code uses the node's full_name for that purpose.
Update the code to use the "%pOF" printf format to
determine the node's full path.
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Having device_nodes be kobjects is only needed if sysfs or OF_DYNAMIC is
enabled. Otherwise, having a kobject in struct device_node is
unnecessary bloat in minimal kernel configurations.
Likewise, bin_attribute is only needed in struct property when sysfs is
enabled, so we can make it configurable too.
Tested-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Frank Rowand <frowand.list@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Rob Herring <robh@kernel.org>
The ref counting is broken for OF_DYNAMIC when sysfs is disabled because
the kobject initialization is skipped. Only the properties
add/remove/update should be skipped for !SYSFS config.
Tested-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Frank Rowand <frowand.list@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Rob Herring <robh@kernel.org>
Do not strdup() console options. It seems that the only reason for
it to be strdup()-ed was a compilation warning: printk, UART and
console drivers, for some reason, expect char pointer instead of
const char pointer. So we can just pass `of_stdout_options', but
need to cast it to char pointer. A better fix would be to change
printk, console drivers and UART to accept const char `options';
but that will take time - there are lots of drivers to update.
The patch also fixes a possible memory leak: add_preferred_console()
can fail, but we don't kfree() options.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Rob Herring <robh@kernel.org>
of_alias_scan() can use of_property_read_string() -- using the modern DT API
adds some prop sanity checks as a bonus; it does add couple LoCs but only
because the original code violated the 80-column limit...
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Rob Herring <robh@kernel.org>
of_n_{addr|size}_cells() predate of_property_read_u32(), so they have to
basically open-code it. Using the modern DT API saves several LoCs and also
adds some prop sanity checks as a bonus...
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.
Signed-off-by: Rob Herring <robh@kernel.org>
find_node_by_full_name() does the same thing as of_find_node_by_path(),
but takes no locks and doesn't work on aliases. Refactor
of_find_node_opts_by_path() into __of_find_node_by_full_path() and
replace find_node_by_full_name() with it.
Signed-off-by: Rob Herring <robh@kernel.org>
Several places in DT code open code the equivalent of kbasename.
Replace them.
The behavior for root nodes in node_name_cmp will be slightly different.
Instead of comparing "/", "" will be compared. The comparison will be
the same.
Reviewed-by: Andy Shevchenko <andy.shevhchenko@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
checkpatch whined about using S_IRUGO instead of octal equivalent
when adding phandle sysfs code, so used octal in that pending patch.
Change other instances of the S_* constants in the same file to
the octal form.
Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
base.c contains both core OF functions and increasingly other
functionality such as accessing properties and graphs, including
convenience functions. In the near future this would also include OF
specific implementation of the fwnode property and graph APIs.
Create driver/of/property.c to contain procedures for accessing and
interpreting device tree properties. The procedures are moved from
drivers/of/base.c, with no changes other than copying only the includes
required by the moved procedures.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rob Herring <robh@kernel.org>
OF graph want to count its endpoint number, same as
of_get_child_count(). This patch adds of_graph_get_endpoint_count()
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Linux kernel already has of_graph_get_remote_port_parent(),
but, sometimes we want to get own port parent.
This patch adds of_graph_get_port_parent()
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
It should use same method to get same result.
To getting remote-endpoint node,
let's use of_graph_get_remote_endpoint()
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
of_for_each_phandle() uses of_phandle_iterator_init/next
but it isn't exported. So kernel module complile will say
ERROR: "of_phandle_iterator_init" [xxx.ko] undefined!
ERROR: "of_phandle_iterator_next" [xxx.ko] undefined!
This patch solved this issue
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
