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2020-01-02of: base: Add of_get_cpu_state_node() to get idle states for a CPU nodeUlf Hansson1-0/+8
The CPU's idle state nodes are currently parsed at the common cpuidle DT library, but also when initializing data for specific CPU idle operations, as in the PSCI cpuidle driver case and qcom-spm cpuidle case. To avoid open-coding, let's introduce of_get_cpu_state_node(), which takes the device node for the CPU and the index to the requested idle state node, as in-parameters. In case a corresponding idle state node is found, it returns the node with the refcount incremented for it, else it returns NULL. Moreover, for PSCI there are two options to describe the CPU's idle states [1], either via a flattened description or a hierarchical layout. Hence, let's take both options into account. [1] Documentation/devicetree/bindings/arm/psci.yaml Suggested-by: Sudeep Holla <sudeep.holla@arm.com> Co-developed-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Lina Iyer <lina.iyer@linaro.org> Reviewed-by: Rob Herring <robh@kernel.org> Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
2019-07-26of: Fix typo in kerneldocThierry Reding1-1/+1
"Findfrom" is not a word. Replace the function synopsis by something that makes sense. Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Rob Herring <robh@kernel.org>
2019-05-01of: fix clang -Wunsequenced for be32_to_cpu()Phong Tran1-2/+2
Now, make the loop explicit to avoid clang warning. ./include/linux/of.h:238:37: warning: multiple unsequenced modifications to 'cell' [-Wunsequenced] r = (r << 32) | be32_to_cpu(*(cell++)); ^~ ./include/linux/byteorder/generic.h:95:21: note: expanded from macro 'be32_to_cpu' ^ ./include/uapi/linux/byteorder/little_endian.h:40:59: note: expanded from macro '__be32_to_cpu' ^ ./include/uapi/linux/swab.h:118:21: note: expanded from macro '__swab32' ___constant_swab32(x) : \ ^ ./include/uapi/linux/swab.h:18:12: note: expanded from macro '___constant_swab32' (((__u32)(x) & (__u32)0x000000ffUL) << 24) | \ ^ Signed-off-by: Phong Tran <tranmanphong@gmail.com> Reported-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://github.com/ClangBuiltLinux/linux/issues/460 Suggested-by: David Laight <David.Laight@ACULAB.COM> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Cc: stable@vger.kernel.org [robh: fix up whitespace] Signed-off-by: Rob Herring <robh@kernel.org>
2019-04-10of: use correct function prototype for of_overlay_fdt_apply()Chris Packham1-1/+2
When CONFIG_OF_OVERLAY is not enabled the fallback stub for of_overlay_fdt_apply() does not match the prototype for the case when CONFIG_OF_OVERLAY is enabled. Update the stub to use the correct function prototype. Fixes: 39a751a4cb7e ("of: change overlay apply input data from unflattened to FDT") Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Reviewed-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2019-01-10of: Remove struct device_node.type pointerRob Herring1-1/+0
Now that all users of device_node.type pointer have been removed in favor of accessor functions, we can remove it. Cc: Frank Rowand <frowand.list@gmail.com> Cc: devicetree@vger.kernel.org Signed-off-by: Rob Herring <robh@kernel.org>
2018-12-28Merge tag 'devicetree-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds1-5/+16
Pull Devicetree updates from Rob Herring: "The biggest highlight here is the start of using json-schema for DT bindings. Being able to validate bindings has been discussed for years with little progress. - Initial support for DT bindings using json-schema language. This is the start of converting DT bindings from free-form text to a structured format. - Reworking of initrd address initialization. This moves to using the phys address instead of virt addr in the DT parsing code. This rework was motivated by CONFIG_DEV_BLK_INITRD causing unnecessary rebuilding of lots of files. - Fix stale phandle entries in phandle cache - DT overlay validation improvements. This exposed several memory leak bugs which have been fixed. - Use node name and device_type helper functions in DT code - Last remaining conversions to using %pOFn printk specifier instead of device_node.name directly - Create new common RTC binding doc and move all trivial RTC devices out of trivial-devices.txt. - New bindings for Freescale MAG3110 magnetometer, Cadence Sierra PHY, and Xen shared memory - Update dtc to upstream version v1.4.7-57-gf267e674d145" * tag 'devicetree-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (68 commits) of: __of_detach_node() - remove node from phandle cache of: of_node_get()/of_node_put() nodes held in phandle cache gpio-omap.txt: add reg and interrupts properties dt-bindings: mrvl,intc: fix a trivial typo dt-bindings: iio: magnetometer: add dt-bindings for freescale mag3110 dt-bindings: Convert trivial-devices.txt to json-schema dt-bindings: arm: mrvl: amend Browstone compatible string dt-bindings: arm: Convert Tegra board/soc bindings to json-schema dt-bindings: arm: Convert ZTE board/soc bindings to json-schema dt-bindings: arm: Add missing Xilinx boards dt-bindings: arm: Convert Xilinx board/soc bindings to json-schema dt-bindings: arm: Convert VIA board/soc bindings to json-schema dt-bindings: arm: Convert ST STi board/soc bindings to json-schema dt-bindings: arm: Convert SPEAr board/soc bindings to json-schema dt-bindings: arm: Convert CSR SiRF board/soc bindings to json-schema dt-bindings: arm: Convert QCom board/soc bindings to json-schema dt-bindings: arm: Convert TI nspire board/soc bindings to json-schema dt-bindings: arm: Convert TI davinci board/soc bindings to json-schema dt-bindings: arm: Convert Calxeda board/soc bindings to json-schema dt-bindings: arm: Convert Altera board/soc bindings to json-schema ...
2018-11-18of: Drop full path from full_name for PDT systemsRob Herring1-1/+0
Now that there are no more users of path_component_name for Sparc outside of the PDT code and all users of device_node.full_name are converted to use "%pOF" printf specifier, we can align Sparc with FDT and store just the base node name and unit address in full_name. This makes path_component_name redundant, so it can be removed. As full_name is used by printf specifiers, set it as early as possible. Cc: Frank Rowand <frowand.list@gmail.com> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08of: overlay: validate overlay properties #address-cells and #size-cellsFrank Rowand1-0/+6
If overlay properties #address-cells or #size-cells are already in the live devicetree for any given node, then the values in the overlay must match the values in the live tree. If the properties are already in the live tree then there is no need to create a changeset entry to add them since they must have the same value. This reduces the memory used by the changeset and eliminates a possible memory leak. Tested-by: Alan Tull <atull@kernel.org> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
2018-11-08of: overlay: add tests to validate kfrees from overlay removalFrank Rowand1-5/+10
Add checks: - attempted kfree due to refcount reaching zero before overlay is removed - properties linked to an overlay node when the node is removed - node refcount > one during node removal in a changeset destroy, if the node was created by the changeset After applying this patch, several validation warnings will be reported from the devicetree unittest during boot due to pre-existing devicetree bugs. The warnings will be similar to: OF: ERROR: of_node_release(), unexpected properties in /testcase-data/overlay-node/test-bus/test-unittest11 OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /testcase-data-2/substation@100/ hvac-medium-2 Tested-by: Alan Tull <atull@kernel.org> Signed-off-by: Frank Rowand <frank.rowand@sony.com>
2018-10-29Merge tag 'tty-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/ttyLinus Torvalds1-0/+10
Pull tty/serial updates from Greg KH: "Here is the big tty and serial pull request for 4.20-rc1 Lots of little things here, including a merge from the SPI tree in order to keep things simpler for everyone to sync around for one platform. Major stuff is: - tty buffer clearing after use - atmel_serial fixes and additions - xilinx uart driver updates and of course, lots of tiny fixes and additions to individual serial drivers. All of these have been in linux-next with no reported issues for a while" * tag 'tty-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (66 commits) of: base: Change logic in of_alias_get_alias_list() of: base: Fix english spelling in of_alias_get_alias_list() serial: sh-sci: do not warn if DMA transfers are not supported serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCES tty: check name length in tty_find_polling_driver() serial: sh-sci: Add r8a77990 support tty: wipe buffer if not echoing data tty: wipe buffer. serial: fsl_lpuart: Remove the alias node dependence TTY: sn_console: Replace spin_is_locked() with spin_trylock() Revert "serial:serial_core: Allow use of CTS for PPS line discipline" serial: 8250_uniphier: add auto-flow-control support serial: 8250_uniphier: flatten probe function serial: 8250_uniphier: remove unused "fifo-size" property dt-bindings: serial: sh-sci: Document r8a7744 bindings serial: uartps: Fix missing unlock on error in cdns_get_id() tty/serial: atmel: add ISO7816 support tty/serial_core: add ISO7816 infrastructure serial:serial_core: Allow use of CTS for PPS line discipline serial: docs: Fix filename for serial reference implementation ...
2018-10-26Merge tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds1-7/+12
Pull Devicetree updates from Rob Herring: "A bit bigger than normal as I've been busy this cycle. There's a few things with dependencies and a few things subsystem maintainers didn't pick up, so I'm taking them thru my tree. The fixes from Johan didn't get into linux-next, but they've been waiting for some time now and they are what's left of what subsystem maintainers didn't pick up. Summary: - Sync dtc with upstream version v1.4.7-14-gc86da84d30e4 - Work to get rid of direct accesses to struct device_node name and type pointers in preparation for removing them. New helpers for parsing DT cpu nodes and conversions to use the helpers. printk conversions to %pOFn for printing DT node names. Most went thru subystem trees, so this is the remainder. - Fixes to DT child node lookups to actually be restricted to child nodes instead of treewide. - Refactoring of dtb targets out of arch code. This makes the support more uniform and enables building all dtbs on c6x, microblaze, and powerpc. - Various DT binding updates for Renesas r8a7744 SoC - Vendor prefixes for Facebook, OLPC - Restructuring of some ARM binding docs moving some peripheral bindings out of board/SoC binding files - New "secure-chosen" binding for secure world settings on ARM - Dual licensing of 2 DT IRQ binding headers" * tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (78 commits) ARM: dt: relicense two DT binding IRQ headers power: supply: twl4030-charger: fix OF sibling-node lookup NFC: nfcmrvl_uart: fix OF child-node lookup net: stmmac: dwmac-sun8i: fix OF child-node lookup net: bcmgenet: fix OF child-node lookup drm/msm: fix OF child-node lookup drm/mediatek: fix OF sibling-node lookup of: Add missing exports of node name compare functions dt-bindings: Add OLPC vendor prefix dt-bindings: misc: bk4: Add device tree binding for Liebherr's BK4 SPI bus dt-bindings: thermal: samsung: Add SPDX license identifier dt-bindings: clock: samsung: Add SPDX license identifiers dt-bindings: timer: ostm: Add R7S9210 support dt-bindings: phy: rcar-gen2: Add r8a7744 support dt-bindings: can: rcar_can: Add r8a7744 support dt-bindings: timer: renesas, cmt: Document r8a7744 CMT support dt-bindings: watchdog: renesas-wdt: Document r8a7744 support dt-bindings: thermal: rcar: Add device tree support for r8a7744 Documentation: dt: Add binding for /secure-chosen/stdout-path dt-bindings: arm: zte: Move sysctrl bindings to their own doc ...
2018-10-04of: Fix property name in of_node_get_device_typeRob Herring1-1/+1
Commit 0413bedabc88 ("of: Add device_type access helper functions") added a new helper not yet used in preparation for some treewide clean up of accesses to 'device_type' properties. Unfortunately, there's an error and 'type' was used for the property name. Fix this. Fixes: 0413bedabc88 ("of: Add device_type access helper functions") Cc: Frank Rowand <frowand.list@gmail.com> Signed-off-by: Rob Herring <robh@kernel.org>
2018-09-28Merge branch 'dt/cpu-type-rework' into dt/nextRob Herring1-0/+11
2018-09-28of: Add cpu node iterator for_each_of_cpu_node()Rob Herring1-0/+11
Iterating thru cpu nodes is a common pattern. Create a common iterator which can find child nodes either by node name or device_type == cpu. Using the former will allow for eventually dropping device_type properties which are deprecated for FDT. Cc: Frank Rowand <frowand.list@gmail.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rob Herring <robh@kernel.org>
2018-09-25iommu/of: make of_pci_map_rid() available for other devices tooNipun Gupta1-0/+11
iommu-map property is also used by devices with fsl-mc. This patch moves the of_pci_map_rid to generic location, so that it can be used by other busses too. 'of_pci_map_rid' is renamed here to 'of_map_rid' and there is no functional change done in the API. Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com> Reviewed-by: Rob Herring <robh@kernel.org> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-09-20of: base: Introduce of_alias_get_alias_list() to check alias IDsMichal Simek1-0/+10
The function travels the lookup table to record alias ids for the given device match structures and alias stem. This function will be used by serial drivers to check if requested alias is allocated or free to use. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-07of: make default address and size cells sizes privateRob Herring1-6/+0
Only some old OpenFirmware implementations rely on default sizes. Any FDT and modern implementation should have explicit properties. Make the OF_ROOT_NODE_*_CELLS_DEFAULT defines private so we don't get any outside users. This also gets us one step closer to removing the asm/prom.h dependency on Sparc. Cc: "David S. Miller" <davem@davemloft.net> Cc: Frank Rowand <frowand.list@gmail.com> Cc: sparclinux@vger.kernel.org Signed-off-by: Rob Herring <robh@kernel.org>
2018-08-31of: Add device_type access helper functionsRob Herring1-0/+12
In preparation to remove direct access to device_node.type, add of_node_is_type() and of_node_get_device_type() helpers to check and retrieve the device type. Cc: Frank Rowand <frowand.list@gmail.com> Signed-off-by: Rob Herring <robh@kernel.org>
2018-08-30of: add node name compare helper functionsRob Herring1-0/+13
In preparation to remove device_node.name pointer, add helper functions for node name comparisons which are a common pattern throughout the kernel. Cc: Frank Rowand <frowand.list@gmail.com> Signed-off-by: Rob Herring <robh@kernel.org>
2018-08-29of: add helper to lookup compatible child nodeJohan Hovold1-0/+8
Add of_get_compatible_child() helper that can be used to lookup compatible child nodes. Several drivers currently use of_find_compatible_node() to lookup child nodes while failing to notice that the of_find_ functions search the entire tree depth-first (from a given start node) and therefore can match unrelated nodes. The fact that these functions also drop a reference to the node they start searching from (e.g. the parent node) is typically also overlooked, something which can lead to use-after-free bugs. Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Rob Herring <robh@kernel.org>
2018-03-05Merge tag 'overlay_apply_fdt_v7-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/frowand/linux into dt/nextRob Herring1-3/+3
DT overlay applying rework from Frank Rowand: "Move duplicating and unflattening of an overlay flattened devicetree (FDT) into the overlay application code. To accomplish this, of_overlay_apply() is replaced by of_overlay_fdt_apply()."
2018-03-04of: change overlay apply input data from unflattened to FDTFrank Rowand1-3/+3
Move duplicating and unflattening of an overlay flattened devicetree (FDT) into the overlay application code. To accomplish this, of_overlay_apply() is replaced by of_overlay_fdt_apply(). The copy of the FDT (aka "duplicate FDT") now belongs to devicetree code, which is thus responsible for freeing the duplicate FDT. The caller of of_overlay_fdt_apply() remains responsible for freeing the original FDT. The unflattened devicetree now belongs to devicetree code, which is thus responsible for freeing the unflattened devicetree. These ownership changes prevent early freeing of the duplicated FDT or the unflattened devicetree, which could result in use after free errors. of_overlay_fdt_apply() is a private function for the anticipated overlay loader. Update unittest.c to use of_overlay_fdt_apply() instead of of_overlay_apply(). Move overlay fragments from artificial locations in drivers/of/unittest-data/tests-overlay.dtsi into one devicetree source file per overlay. This led to changes in drivers/of/unitest-data/Makefile and drivers/of/unitest.c. - Add overlay directives to the overlay devicetree source files so that dtc will compile them as true overlays into one FDT data chunk per overlay. - Set CFLAGS for drivers/of/unittest-data/testcases.dts so that symbols will be generated for overlay resolution of overlays that are no longer artificially contained in testcases.dts - Unflatten and apply each unittest overlay FDT using of_overlay_fdt_apply(). - Enable the of_resolve_phandles() check for whether the unflattened overlay is detached. This check was previously disabled because the overlays from tests-overlay.dtsi were not unflattened into detached trees. - Other changes to unittest.c infrastructure to manage multiple test FDTs built into the kernel image (access by name instead of arbitrary number). - of_unittest_overlay_high_level(): previously unused code to add properties from the overlay_base devicetree to the live tree was triggered by the restructuring of tests-overlay.dtsi and thus testcases.dts. This exposed two bugs: (1) the need to dup a property before adding it, and (2) property 'name' is auto-generated in the unflatten code and thus will be a duplicate in the __symbols__ node - do not treat this duplicate as an error. Signed-off-by: Frank Rowand <frank.rowand@sony.com>
2018-02-12of: Support parsing phandle argument lists through a nexus nodeStephen Boyd1-0/+12
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>
2018-02-01Merge tag 'devicetree-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds1-5/+1
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 ...
2018-01-08of: Use SPDX license tag for DT filesRob Herring1-5/+1
Convert remaining DT files to use SPDX-License-Identifier tags. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Reviewed-by: Frank Rowand <frank.rowand@sony.com> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Rob Herring <robh@kernel.org>
2018-01-02of: Add helper for mapping device node to logical CPU numberSuzuki K Poulose1-0/+7
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>
2017-11-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-12/+50
Pull networking updates from David Miller: "Highlights: 1) Maintain the TCP retransmit queue using an rbtree, with 1GB windows at 100Gb this really has become necessary. From Eric Dumazet. 2) Multi-program support for cgroup+bpf, from Alexei Starovoitov. 3) Perform broadcast flooding in hardware in mv88e6xxx, from Andrew Lunn. 4) Add meter action support to openvswitch, from Andy Zhou. 5) Add a data meta pointer for BPF accessible packets, from Daniel Borkmann. 6) Namespace-ify almost all TCP sysctl knobs, from Eric Dumazet. 7) Turn on Broadcom Tags in b53 driver, from Florian Fainelli. 8) More work to move the RTNL mutex down, from Florian Westphal. 9) Add 'bpftool' utility, to help with bpf program introspection. From Jakub Kicinski. 10) Add new 'cpumap' type for XDP_REDIRECT action, from Jesper Dangaard Brouer. 11) Support 'blocks' of transformations in the packet scheduler which can span multiple network devices, from Jiri Pirko. 12) TC flower offload support in cxgb4, from Kumar Sanghvi. 13) Priority based stream scheduler for SCTP, from Marcelo Ricardo Leitner. 14) Thunderbolt networking driver, from Amir Levy and Mika Westerberg. 15) Add RED qdisc offloadability, and use it in mlxsw driver. From Nogah Frankel. 16) eBPF based device controller for cgroup v2, from Roman Gushchin. 17) Add some fundamental tracepoints for TCP, from Song Liu. 18) Remove garbage collection from ipv6 route layer, this is a significant accomplishment. From Wei Wang. 19) Add multicast route offload support to mlxsw, from Yotam Gigi" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2177 commits) tcp: highest_sack fix geneve: fix fill_info when link down bpf: fix lockdep splat net: cdc_ncm: GetNtbFormat endian fix openvswitch: meter: fix NULL pointer dereference in ovs_meter_cmd_reply_start netem: remove unnecessary 64 bit modulus netem: use 64 bit divide by rate tcp: Namespace-ify sysctl_tcp_default_congestion_control net: Protect iterations over net::fib_notifier_ops in fib_seq_sum() ipv6: set all.accept_dad to 0 by default uapi: fix linux/tls.h userspace compilation error usbnet: ipheth: prevent TX queue timeouts when device not ready vhost_net: conditionally enable tx polling uapi: fix linux/rxrpc.h userspace compilation errors net: stmmac: fix LPI transitioning for dwmac4 atm: horizon: Fix irq release error net-sysfs: trigger netlink notification on ifalias change via sysfs openvswitch: Using kfree_rcu() to simplify the code openvswitch: Make local function ovs_nsh_key_attr_size() static openvswitch: Fix return value check in ovs_meter_cmd_features() ...
2017-11-14Merge tag 'devicetree-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds1-21/+24
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 ...
2017-11-08of: add of_property_read_variable_* dummy helpersArnd Bergmann1-12/+50
Commit a67e9472da42 ("of: Add array read functions with min/max size limits") added a new interface for reading variable-length arrays from DT properties. One user was added in dsa recently and this causes a build error because that code can be built with CONFIG_OF disabled: net/dsa/dsa2.c: In function 'dsa_switch_parse_member_of': net/dsa/dsa2.c:678:7: error: implicit declaration of function 'of_property_read_variable_u32_array'; did you mean 'of_property_read_u32_array'? [-Werror=implicit-function-declaration] This adds a dummy functions for of_property_read_variable_u32_array() and a few others that had been missing here. I decided to move of_property_read_string() and of_property_read_string_helper() in the process to make it easier to compare the two sets of function prototypes to make sure they match. Fixes: 975e6e32215e ("net: dsa: rework switch parsing") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-17of: overlay: avoid race condition between applying multiple overlaysFrank Rowand1-3/+0
The process of applying an overlay consists of: - unflatten an overlay FDT (flattened device tree) into an EDT (expanded device tree) - fixup the phandle values in the overlay EDT to fit in a range above the phandle values in the live device tree - create the overlay changeset to reflect the contents of the overlay EDT - apply the overlay changeset, to modify the live device tree, potentially changing the maximum phandle value in the live device tree There is currently no protection against two overlay applies concurrently determining what range of phandle values are in use in the live device tree, and subsequently changing that range. Add a mutex to prevent multiple overlay applies from occurring simultaneously. Move of_resolve_phandles() into of_overlay_apply() so that it does not have to be duplicated by each caller of of_overlay_apply(). The test in of_resolve_phandles() that the overlay tree is detached is temporarily disabled so that old style overlay unittests do not fail. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: detect cases where device tree may become corruptFrank Rowand1-5/+5
When an attempt to apply an overlay changeset fails, an effort is made to revert any partial application of the changeset. When an attempt to remove an overlay changeset fails, an effort is made to re-apply any partial reversion of the changeset. The existing code does not check for failure to recover a failed overlay changeset application or overlay changeset revert. Add the missing checks and flag the devicetree as corrupt if the state of the devicetree can not be determined. Improve and expand the returned errors to more fully reflect the result of the effort to undo the partial effects of a failed attempt to apply or remove an overlay changeset. If the device tree might be corrupt, do not allow further attempts to apply or remove an overlay changeset. When creating an overlay changeset from an overlay device tree, add some additional warnings if the state of the overlay device tree is not as expected. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-17of: overlay: rename identifiers to more reflect what they doFrank Rowand1-6/+6
This patch is aimed primarily at drivers/of/overlay.c, but those changes also have a small impact in a few other files. overlay.c is difficult to read and maintain. Improve readability: - Rename functions, types and variables to better reflect what they do and to be consistent with names in other places, such as the device tree overlay FDT (flattened device tree), and make the algorithms more clear - Use the same names consistently throughout the file - Update comments for name changes - Fix incorrect comments This patch is intended to not introduce any functional change. Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-10-16of: make kobject and bin_attribute support configurableRob Herring1-12/+10
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>
2017-10-16of: wrap accesses to device_node kobjectRob Herring1-0/+2
In preparation to make kobject element in struct device_node optional, provide and use a macro to return the kobject pointer. The only user outside the DT core is the driver core. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 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>
2017-10-16of: make struct property _flags field configurableRob Herring1-0/+4
Only Sparc and CONFIG_OF_DYNAMIC use the struct property._flags field, so make it conditional shrinking struct property a bit. 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>
2017-10-16of: remove struct property.unique_id for FDTRob Herring1-0/+2
Only Sparc uses unique_id, so remove it for FDT builds and shrink struct property a bit making the unflattened DT less of a memory hog. 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>
2017-10-13include/linux/of.h: provide of_n_{addr,size}_cells wrappers for !CONFIG_OFArnd Bergmann1-0/+10
The pci-rcar driver is enabled for compile tests, and this has shown that the driver cannot build without CONFIG_OF, following the inclusion of commit f8f2fe7355fb ("PCI: rcar: Use new OF interrupt mapping when possible"): drivers/pci/host/pcie-rcar.c: In function 'pci_dma_range_parser_init': drivers/pci/host/pcie-rcar.c:1039:2: error: implicit declaration of function 'of_n_addr_cells' [-Werror=implicit-function-declaration] parser->pna = of_n_addr_cells(node); ^ As pointed out by Ben Dooks and Geert Uytterhoeven, this is actually supposed to build fine, which we can achieve if we make the declaration of of_irq_parse_and_map_pci conditional on CONFIG_OF and provide an empty inline function otherwise, as we do for a lot of other of interfaces. This lets us build the rcar_pci driver again without CONFIG_OF for build testing. All platforms using this driver select OF, so this doesn't change anything for the users. [akpm@linux-foundation.org: be consistent with surrounding code] Link: http://lkml.kernel.org/r/20170911200805.3363318-1-arnd@arndb.de Fixes: c25da4778803 ("PCI: rcar: Add Renesas R-Car PCIe driver") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Frank Rowand <frank.rowand@sony.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Magnus Damm <damm@opensource.se> Cc: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-22device property: Get rid of struct fwnode_handle type fieldSakari Ailus1-2/+1
Instead of relying on the struct fwnode_handle type field, define fwnode_operations structs for all separate types of fwnodes. To find out the type, compare to the ops field to relevant ops structs. This change has two benefits: 1. it avoids adding the type field to each and every instance of struct fwnode_handle, thus saving memory and 2. makes the ops field the single factor that defines both the types of the fwnode as well as defines the implementation of its operations, decreasing the possibility of bugs when developing code dealing with fwnode internals. Suggested-by: Rob Herring <robh@kernel.org> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-07-10Merge tag 'devprop-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds1-0/+2
Pull device properties framework updates from Rafael Wysocki: "These mostly rearrange the device properties core code and add a few helper functions to it as a foundation for future work. Specifics: - Rearrange the core device properties code by moving the code specific to each supported platform configuration framework (ACPI, DT and build-in) into a separate file (Sakari Ailus). - Add helper functions for accessing device properties in a firmware-agnostic way (Sakari Ailus, Kieran Bingham)" * tag 'devprop-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: device property: Add fwnode_graph_get_port_parent device property: Add FW type agnostic fwnode_graph_get_remote_node device property: Introduce fwnode_device_is_available() device property: Move fwnode graph ops to firmware specific locations device property: Move FW type specific functionality to FW specific files ACPI: Constify argument to acpi_device_is_present()
2017-07-05Merge branch 'dt/property-move' into dt/nextRob Herring1-10/+20
2017-06-22device property: Move FW type specific functionality to FW specific filesSakari Ailus1-0/+2
The device and fwnode property API supports Devicetree, ACPI and pset properties. The implementation of this functionality for each firmware type was embedded in the fwnode property core. Move it out to firmware type specific locations, making it easier to maintain. Depends-on: ("of: Move OF property and graph API from base.c to property.c") Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-06-14of: Provide dummy of_device_compatible_match() for compile-testingGeert Uytterhoeven1-0/+6
Most of_device_*() functions have dummy versions for CONFIG_OF=n, but of_device_compatible_match() hasn't. Fix that to improve the ability to do compile-testing. Fixes: b9c13fe32faaa71c ("dt: Add of_device_compatible_match()") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rob Herring <robh@kernel.org>
2017-06-01of: Support const and non-const use for to_of_node()Sakari Ailus1-8/+12
Turn to_of_node() into a macro in order to support both const and non-const use. Additionally make the fwnode argument to is_of_node() const as well. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-06-01of: Make of_fwnode_handle() saferSakari Ailus1-1/+7
On the expense of a little bit more complexity in the of_fwnode_handle() macro, make the macro result in NULL in case its argument is NULL while still referencing it only once. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> Signed-off-by: Rob Herring <robh@kernel.org>
2017-05-05Merge tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds1-0/+3
Pull powerpc updates from Michael Ellerman: "Highlights include: - Larger virtual address space on 64-bit server CPUs. By default we use a 128TB virtual address space, but a process can request access to the full 512TB by passing a hint to mmap(). - Support for the new Power9 "XIVE" interrupt controller. - TLB flushing optimisations for the radix MMU on Power9. - Support for CAPI cards on Power9, using the "Coherent Accelerator Interface Architecture 2.0". - The ability to configure the mmap randomisation limits at build and runtime. - Several small fixes and cleanups to the kprobes code, as well as support for KPROBES_ON_FTRACE. - Major improvements to handling of system reset interrupts, correctly treating them as NMIs, giving them a dedicated stack and using a new hypervisor call to trigger them, all of which should aid debugging and robustness. - Many fixes and other minor enhancements. Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt, Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy, Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy, Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin, Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C. Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar, Yang Shi" * tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits) powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it powerpc/powernv: Fix TCE kill on NVLink2 powerpc/mm/radix: Drop support for CPUs without lockless tlbie powerpc/book3s/mce: Move add_taint() later in virtual mode powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body powerpc/smp: Document irq enable/disable after migrating IRQs powerpc/mpc52xx: Don't select user-visible RTAS_PROC powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset() powerpc/eeh: Clean up and document event handling functions powerpc/eeh: Avoid use after free in eeh_handle_special_event() cxl: Mask slice error interrupts after first occurrence cxl: Route eeh events to all drivers in cxl_pci_error_detected() cxl: Force context lock during EEH flow powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST powerpc/xmon: Teach xmon oops about radix vectors powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids powerpc/pseries: Enable VFIO powerpc/powernv: Fix iommu table size calculation hook for small tables powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc powerpc: Add arch/powerpc/tools directory ...
2017-04-03drivers/of/base.c: Add of_property_read_u64_indexAlistair Popple1-0/+3
There is of_property_read_u32_index but no u64 variant. This patch adds one similar to the u32 version for u64. Signed-off-by: Alistair Popple <alistair@popple.id.au> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-29of: Add of_fwnode_handle() to convert device nodes to fwnode_handleSakari Ailus1-0/+4
of_fwnode_handle() returns a struct fwnode_handle of the struct device_node. This may be used on the fwnode property API. Use a macro instead of a function in order to support const and non-const arguments. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-01-17of: base: add support to find the level of the last cacheSudeep Holla1-0/+1
It is useful to have helper function just to get the number of cache levels for a given logical cpu. We can obtain the same by just checking the level at which the last cache is present. This patch adds support to find the level of the last cache for a given cpu. It will be used on ARM64 platform where the device tree provides the information for the additional non-architected/transparent/external last level caches that are not integrated with the processors. Cc: Mark Rutland <mark.rutland@arm.com> Suggested-by: Rob Herring <robh+dt@kernel.org> Acked-by: Rob Herring <robh+dt@kernel.org> Tested-by: Tan Xiaojun <tanxiaojun@huawei.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> [will: use u32 instead of int for cache_level] Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-10of/overlay: add of overlay notificationsAlan Tull1-0/+25
This patch add of overlay notifications. When DT overlays are being added, some drivers/subsystems need to see device tree overlays before the changes go into the live tree. This is distinct from reconfig notifiers that are post-apply or post-remove and which issue very granular notifications without providing access to the context of a whole overlay. The following 4 notificatons are issued: OF_OVERLAY_PRE_APPLY OF_OVERLAY_POST_APPLY OF_OVERLAY_PRE_REMOVE OF_OVERLAY_POST_REMOVE In the case of pre-apply notification, if the notifier returns error, the overlay will be rejected. This patch exports two functions for registering/unregistering notifications: of_overlay_notifier_register(struct notifier_block *nb) of_overlay_notifier_unregister(struct notifier_block *nb) The of_mutex is held during these notifications. The notification data includes pointers to the overlay target and the overlay: struct of_overlay_notify_data { struct device_node *overlay; struct device_node *target; }; Signed-off-by: Alan Tull <atull@opensource.altera.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Moritz Fischer <moritz.fischer@ettus.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15of: Add array read functions with min/max size limitsRichard Fitzgerald1-12/+132
Add a new set of array reading functions that take a minimum and maximum size limit and will fail if the property size is not within the size limits. This makes it more convenient for drivers that use variable-size DT arrays which must be bounded at both ends - data must be at least N entries but must not overflow the array it is being copied into. It is also more efficient than making this functionality out of existing public functions and avoids duplication. The existing array functions have been left in the API, since there are a very large number of clients of those functions and their existing functionality is still useful. This avoids turning a small API improvement into a major kernel rework. The old functions have been turned into mininmal static inlines calling the new functions. The old functions had no upper limit on the actual size of the dts entry, to preserve this functionality rather than keeping two near-identical implementations, if the new function is called with max=0 there is no limit on the size of the dts entry but only the min number of elements are read. Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com> Signed-off-by: Rob Herring <robh@kernel.org>