diff --git a/.codespellrc b/.codespellrc index 14770824d320c..4ed2e6b695cf6 100644 --- a/.codespellrc +++ b/.codespellrc @@ -9,6 +9,7 @@ exclude-file = .codespell-ignore-lines skip = LICENSE, */CODEOWNERS, + */system/zbus/images/*, # Ignore seemingly misspelled words. # lowercase: case insensitive diff --git a/Documentation/applications/system/zbus/images/zbus_anatomy.svg b/Documentation/applications/system/zbus/images/zbus_anatomy.svg new file mode 100644 index 0000000000000..e9bc6c79cefc9 --- /dev/null +++ b/Documentation/applications/system/zbus/images/zbus_anatomy.svg @@ -0,0 +1,3 @@ + + + diff --git a/Documentation/applications/system/zbus/images/zbus_observation_mask.svg b/Documentation/applications/system/zbus/images/zbus_observation_mask.svg new file mode 100644 index 0000000000000..4405a8f3e4aed --- /dev/null +++ b/Documentation/applications/system/zbus/images/zbus_observation_mask.svg @@ -0,0 +1,152 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/Documentation/applications/system/zbus/images/zbus_operations.svg b/Documentation/applications/system/zbus/images/zbus_operations.svg new file mode 100644 index 0000000000000..419cc6c3d5d5f --- /dev/null +++ b/Documentation/applications/system/zbus/images/zbus_operations.svg @@ -0,0 +1,49 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/Documentation/applications/system/zbus/images/zbus_overview.svg b/Documentation/applications/system/zbus/images/zbus_overview.svg new file mode 100644 index 0000000000000..24861bbbe3375 --- /dev/null +++ b/Documentation/applications/system/zbus/images/zbus_overview.svg @@ -0,0 +1,3 @@ + + + diff --git a/Documentation/applications/system/zbus/images/zbus_type_of_observers.svg b/Documentation/applications/system/zbus/images/zbus_type_of_observers.svg new file mode 100644 index 0000000000000..1bc29e3dadf16 --- /dev/null +++ b/Documentation/applications/system/zbus/images/zbus_type_of_observers.svg @@ -0,0 +1,18 @@ + + + + + + + + + + + + + + + + + + diff --git a/Documentation/applications/system/zbus/index.rst b/Documentation/applications/system/zbus/index.rst new file mode 100644 index 0000000000000..e91b2ec593a62 --- /dev/null +++ b/Documentation/applications/system/zbus/index.rst @@ -0,0 +1,209 @@ +========================== +``zbus`` ZBus message bus +========================== + +Port of the `zbus `_ +message bus to NuttX, built entirely on native NuttX primitives. ZBus +implements many-to-many communication through **channels** (typed shared +messages) observed by **observers**, keeping publishers and consumers +fully decoupled. + +.. figure:: images/zbus_overview.svg + :alt: zbus usage overview + :width: 75% + + A typical zbus application architecture. + +Channels and observers are defined statically, in any source file, with +declarative macros. The definitions are collected at link time through +iterable sections (see the Iterable Sections component documentation) -- +there is no runtime registration and no central list to maintain. + +.. figure:: images/zbus_anatomy.svg + :alt: zbus anatomy + :width: 70% + + ZBus anatomy: channels, observers and observations. + +Observer types +============== + +.. figure:: images/zbus_type_of_observers.svg + :alt: zbus observer types + :width: 70% + + The four observer types. + +======================== =================================================== +Type Behavior +======================== =================================================== +Listener Callback executed synchronously in the publisher + context (``ZBUS_LISTENER_DEFINE``). +Subscriber Receives channel references through a message + queue; waits with ``zbus_sub_wait()`` + (``ZBUS_SUBSCRIBER_DEFINE``). +Message subscriber Receives a *copy* of every published message, in + order; waits with ``zbus_sub_wait_msg()`` + (``ZBUS_MSG_SUBSCRIBER_DEFINE``, + ``CONFIG_ZBUS_MSG_SUBSCRIBER``). +Async listener Callback executed on a dedicated task with a + copy of the message + (``ZBUS_ASYNC_LISTENER_DEFINE``, + ``CONFIG_ZBUS_ASYNC_LISTENER``). +======================== =================================================== + +Runtime observers (``zbus_chan_add_obs()``/``zbus_chan_rm_obs()``, +``CONFIG_ZBUS_RUNTIME_OBSERVERS``), per-observation notification masks, +observer enable/disable, message validators and channel user data are +also supported. + +.. figure:: images/zbus_observation_mask.svg + :alt: zbus observation mask + :width: 75% + + Observer enable/disable and per-observation masks: disabling the + observer (b) silences every channel; masking observations (c, d) + silences individual channels. + +Example +======= + +The figure below shows the kind of decoupled architecture zbus enables: +every block only talks to channels, so each one can be replaced without +touching the others. + +.. figure:: images/zbus_operations.svg + :alt: zbus sensor-based application + :width: 85% + + A sensor-based application built on zbus. + +.. code-block:: c + + #include + + struct acc_msg + { + int x; + int y; + int z; + }; + + static void listener_cb(const struct zbus_channel *chan) + { + const struct acc_msg *msg = zbus_chan_const_msg(chan); + printf("x=%d y=%d z=%d\n", msg->x, msg->y, msg->z); + } + + ZBUS_LISTENER_DEFINE(acc_listener, listener_cb); + ZBUS_SUBSCRIBER_DEFINE(acc_subscriber, 4); + + ZBUS_CHAN_DEFINE(acc_chan, /* Name */ + struct acc_msg, /* Message type */ + NULL, /* Validator */ + NULL, /* User data */ + ZBUS_OBSERVERS(acc_listener, /* Observers, in */ + acc_subscriber),/* priority order */ + ZBUS_MSG_INIT(.x = 0, .y = 0, .z = 0)); + + /* Publisher: */ + + struct acc_msg msg = { 1, 10, 100 }; + zbus_chan_pub(&acc_chan, &msg, 1000); + + /* Subscriber thread: */ + + const struct zbus_channel *chan; + if (zbus_sub_wait(&acc_subscriber, &chan, ZBUS_FOREVER) == 0) + { + zbus_chan_read(chan, &msg, 500); + } + +A complete runnable example is available in ``apps/examples/zbus`` +(``CONFIG_EXAMPLES_ZBUS``), and a cmocka test suite covering the whole +API in ``apps/testing/zbus`` (``CONFIG_TESTING_ZBUS``). + +Not ported +========== + +The following Zephyr zbus features are **not available** in this port: + +* **Multi-domain proxy agent** (``CONFIG_ZBUS_PROXY_AGENT``): bridges + channels between domains/cores over IPC. Experimental upstream and + tied to the Zephyr IPC service; a NuttX equivalent would be built on + rpmsg and is left as future work. +* **Publishing from interrupt handlers**: the Zephyr original allows + ``zbus_chan_pub()`` from ISRs with ``K_NO_WAIT``. This port is a + userspace library and its primitives (semaphores, message queues, lazy + initialization) are not ISR-safe: interrupt handling belongs to the + driver, which should hand the data to a thread (the usual NuttX + pattern) that then publishes it. ``test_timer_driven_publisher`` in + ``apps/testing/zbus`` shows the pattern with a kernel timer interrupt + delivering a signal to a sampling thread. +* **Priority boost (Highest Locker Protocol)** + (``CONFIG_ZBUS_PRIORITY_BOOST``): the Zephyr hand-rolled protection + against priority inversion during the notification process. Not + needed: enable the native ``CONFIG_PRIORITY_INHERITANCE`` so the + channel semaphores get equivalent protection from the kernel. +* **net_buf pools and pool isolation** + (``CONFIG_ZBUS_MSG_SUBSCRIBER_BUF_*``): obsolete by design in this + port -- message queues copy the payload on ``mq_send``, so no shared + reference-counted buffers exist at all. +* **Static/user-provided runtime observer nodes** + (``CONFIG_ZBUS_RUNTIME_OBSERVERS_NODE_ALLOC_STATIC/NONE``): runtime + observer nodes are always heap-allocated in this port. + +Differences from the Zephyr original +==================================== + +* Timeouts are plain milliseconds (``int32_t``): ``ZBUS_NO_WAIT`` (0) and + ``ZBUS_FOREVER`` (-1) replace ``K_NO_WAIT``/``K_FOREVER``. +* Subscriber queues are POSIX message queues opened lazily on first API + use through the kernel ``file_mq_*`` interface, making them usable from + any task (a ``mqd_t`` descriptor would die with the opening task). +* Initialization is lazy (``pthread_once`` on the first API call) + replacing the Zephyr ``SYS_INIT`` hook; no explicit init call is + needed. +* Async listeners run on a dedicated task per listener (spawned on + first use; priority and stack size are configurable) instead of the + Zephyr system work queue. + +Configuration +============= + +Requirements: + +* The board linker script must provide the zbus iterable sections, either + by including ```` inside ``.text`` (see the + ``linum-stm32h753bi`` board) or through ``CONFIG_ZBUS_LINKER_INSERT`` + (zero-touch mode; see its help text for the MEMORY-layout constraint). +* ``CONFIG_MQ_MAXMSGSIZE`` must be at least + ``CONFIG_ZBUS_MSG_SUBSCRIBER_MAX_MSG_SIZE`` plus the size of a pointer + when message subscribers or async listeners are used, otherwise their + queues fail to open with ``-EINVAL``. +* FLAT build (the library uses the kernel ``file_mq_*`` interface + directly). + +Main options: + +* ``CONFIG_ZBUS`` -- enable the library. +* ``CONFIG_ZBUS_CHANNEL_NAME`` / ``CONFIG_ZBUS_OBSERVER_NAME`` -- name + fields and lookup by name. +* ``CONFIG_ZBUS_CHANNEL_ID`` -- numeric channel identifiers + (``ZBUS_CHAN_DEFINE_WITH_ID``, ``zbus_chan_from_id()``). +* ``CONFIG_ZBUS_MSG_SUBSCRIBER`` -- message subscribers + (+ ``_MAX_MSG_SIZE``, ``_QUEUE_SIZE``). +* ``CONFIG_ZBUS_ASYNC_LISTENER`` -- async listeners (+ ``_PRIORITY``, + ``_STACKSIZE`` of their tasks). +* ``CONFIG_ZBUS_RUNTIME_OBSERVERS`` -- runtime observers. +* ``CONFIG_ZBUS_CHANNEL_PUBLISH_STATS`` -- publish timestamp/count. +* ``CONFIG_ZBUS_ASSERT_MOCK`` -- invalid parameters return ``-EFAULT`` + instead of asserting (for tests). + +Credits +======= + +The zbus design and the diagrams in this page come from the upstream +`Zephyr zbus documentation +`_ +by Rodrigo Peixoto and contributors (Apache License 2.0). diff --git a/Documentation/platforms/arm/stm32h7/boards/linum-stm32h753bi/index.rst b/Documentation/platforms/arm/stm32h7/boards/linum-stm32h753bi/index.rst index 9b469c9c80af3..01e0e026c1790 100644 --- a/Documentation/platforms/arm/stm32h7/boards/linum-stm32h753bi/index.rst +++ b/Documentation/platforms/arm/stm32h7/boards/linum-stm32h753bi/index.rst @@ -1298,3 +1298,28 @@ This example demonstrates how to use the CAN-FD peripherals can0 and can1 with t can0 051 [8] 00 11 22 33 44 55 66 77 can0 051 [16] 00 11 22 33 44 55 66 77 88 99 AA BB CC DD EE FF + +zbus +---- + +Enables the zbus message bus library (``apps/system/zbus``, a port of the +Zephyr zbus — see :doc:`its documentation +`) with all observer types (listeners, +subscribers, message subscribers, async listeners, ISR publisher and +runtime observers), together with its example application:: + + nsh> zbus + zbus: publishing 5 messages to acc_chan + zbus: listener: x=1 y=10 z=100 + zbus: subscriber: x=1 y=10 z=100 + ... + zbus: done + +The cmocka test suite from ``apps/testing/zbus`` is also included and can +be used to validate the whole zbus API on the board:: + + nsh> cmocka_zbus_test + [==========] tests: Running 16 test(s). + ... + [==========] tests: 16 test(s) run. + [ PASSED ] 16 test(s). diff --git a/boards/arm/stm32h7/linum-stm32h753bi/configs/zbus/defconfig b/boards/arm/stm32h7/linum-stm32h753bi/configs/zbus/defconfig new file mode 100644 index 0000000000000..ea87116489927 --- /dev/null +++ b/boards/arm/stm32h7/linum-stm32h753bi/configs/zbus/defconfig @@ -0,0 +1,74 @@ +# +# This file is autogenerated: PLEASE DO NOT EDIT IT. +# +# You can use "make menuconfig" to make any modifications to the installed .config file. +# You can then do "make savedefconfig" to generate a new defconfig file that includes your +# modifications. +# +# CONFIG_STANDARD_SERIAL is not set +CONFIG_ALLOW_MIT_COMPONENTS=y +CONFIG_ARCH="arm" +CONFIG_ARCH_BOARD="linum-stm32h753bi" +CONFIG_ARCH_BOARD_LINUM_STM32H753BI=y +CONFIG_ARCH_CHIP="stm32h7" +CONFIG_ARCH_CHIP_STM32=y +CONFIG_ARCH_CHIP_STM32H753BI=y +CONFIG_ARCH_CHIP_STM32H7=y +CONFIG_ARCH_CHIP_STM32H7_CORTEXM7=y +CONFIG_ARCH_INTERRUPTSTACK=2048 +CONFIG_ARCH_SETJMP_H=y +CONFIG_ARCH_STACKDUMP=y +CONFIG_ARMV7M_DCACHE=y +CONFIG_ARMV7M_DCACHE_WRITETHROUGH=y +CONFIG_ARMV7M_DTCM=y +CONFIG_ARMV7M_ICACHE=y +CONFIG_BOARD_LOOPSPERMSEC=43103 +CONFIG_BUILTIN=y +CONFIG_DEBUG_FEATURES=y +CONFIG_DEBUG_SYMBOLS=y +CONFIG_EXAMPLES_ALARM=y +CONFIG_EXAMPLES_ZBUS=y +CONFIG_FS_PROCFS=y +CONFIG_IDLETHREAD_STACKSIZE=2048 +CONFIG_INIT_ENTRYPOINT="nsh_main" +CONFIG_INIT_STACKSIZE=4096 +CONFIG_INTELHEX_BINARY=y +CONFIG_LIBM=y +CONFIG_LINE_MAX=64 +CONFIG_MM_REGIONS=4 +CONFIG_MQ_MAXMSGSIZE=96 +CONFIG_NSH_BUILTIN_APPS=y +CONFIG_NSH_DISABLE_IFUPDOWN=y +CONFIG_NSH_DISABLE_VCONFIG=y +CONFIG_NSH_FILEIOSIZE=512 +CONFIG_NSH_READLINE=y +CONFIG_PREALLOC_TIMERS=4 +CONFIG_RAM_SIZE=245760 +CONFIG_RAM_START=0x20010000 +CONFIG_RAW_BINARY=y +CONFIG_RR_INTERVAL=200 +CONFIG_RTC_ALARM=y +CONFIG_RTC_DATETIME=y +CONFIG_RTC_DRIVER=y +CONFIG_SCHED_CPULOAD_SYSCLK=y +CONFIG_SCHED_WAITPID=y +CONFIG_STACK_COLORATION=y +CONFIG_START_DAY=6 +CONFIG_START_MONTH=12 +CONFIG_START_YEAR=2011 +CONFIG_STM32_PWR=y +CONFIG_STM32_RTC=y +CONFIG_STM32_USART1=y +CONFIG_SYSTEM_NSH=y +CONFIG_TASK_NAME_SIZE=20 +CONFIG_TESTING_CMOCKA=y +CONFIG_TESTING_ZBUS=y +CONFIG_USART1_SERIAL_CONSOLE=y +CONFIG_ZBUS=y +CONFIG_ZBUS_ASYNC_LISTENER=y +CONFIG_ZBUS_CHANNEL_ID=y +CONFIG_ZBUS_CHANNEL_NAME=y +CONFIG_ZBUS_CHANNEL_PUBLISH_STATS=y +CONFIG_ZBUS_MSG_SUBSCRIBER=y +CONFIG_ZBUS_OBSERVER_NAME=y +CONFIG_ZBUS_RUNTIME_OBSERVERS=y diff --git a/boards/arm/stm32h7/linum-stm32h753bi/scripts/flash.ld b/boards/arm/stm32h7/linum-stm32h753bi/scripts/flash.ld index b726e5c457607..036b6b4c5ebf5 100644 --- a/boards/arm/stm32h7/linum-stm32h753bi/scripts/flash.ld +++ b/boards/arm/stm32h7/linum-stm32h753bi/scripts/flash.ld @@ -126,6 +126,7 @@ SECTIONS *(.got) *(.gcc_except_table) *(.gnu.linkonce.r.*) +#include _etext = ABSOLUTE(.); } > flash @@ -156,6 +157,7 @@ SECTIONS *(.data .data.*) *(.gnu.linkonce.d.*) CONSTRUCTORS +#include . = ALIGN(4); _edata = ABSOLUTE(.); } > sram AT > flash diff --git a/include/nuttx/linker/zbus.ld b/include/nuttx/linker/zbus.ld new file mode 100644 index 0000000000000..d8ee0aa0cc67c --- /dev/null +++ b/include/nuttx/linker/zbus.ld @@ -0,0 +1,67 @@ +/**************************************************************************** + * include/nuttx/linker/zbus.ld + * + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. The + * ASF licenses this file to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance with the + * License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the + * License for the specific language governing permissions and limitations + * under the License. + * + ****************************************************************************/ + +/* Supplementary linker script providing the zbus iterable sections without + * editing the board linker script ("zero-touch" mode). Selected by + * CONFIG_ZBUS_LINKER_INSERT, which adds this file to ARCHSCRIPT (see + * tools/Config.mk). The INSERT command makes this script supplement -- + * not replace -- the board script. + * + * Constraints of this mode: + * - GNU ld only (INSERT is not supported by macOS ld64), and the INSERT + * script must come BEFORE the board script on the command line (the + * ARCHSCRIPT hook guarantees that ordering). + * - The board script must define an output section named ".text". + * - The ROM/flash region must be the first MEMORY region compatible + * with read-only sections: GNU ld assigns the INSERTed section to a + * region by attribute matching in declaration order, so a board that + * declares a generic rwx region at a lower address first (e.g. ITCM + * at 0x0) would pull these sections into the wrong region. Such + * boards must use the include instead. + * + * Boards that include in their script should + * NOT enable CONFIG_ZBUS_LINKER_INSERT (the common-rom.ld zbus block is + * disabled when this mode is selected, so enabling it by mistake is + * harmless but pointless). + */ + +SECTIONS +{ + .zbus : SUBALIGN(4) + { + . = ALIGN(4); + _zbus_channel_list_start = .; + KEEP(*(SORT_BY_NAME(._zbus_channel.static.*))); + _zbus_channel_list_end = .; + + . = ALIGN(4); + _zbus_observer_list_start = .; + KEEP(*(SORT_BY_NAME(._zbus_observer.static.*))); + _zbus_observer_list_end = .; + + . = ALIGN(4); + _zbus_channel_observation_list_start = .; + KEEP(*(SORT_BY_NAME(._zbus_channel_observation.static.*))); + _zbus_channel_observation_list_end = .; + } +} +INSERT AFTER .text; diff --git a/tools/Config.mk b/tools/Config.mk index bc5d2ffd54256..b86b896bb5346 100644 --- a/tools/Config.mk +++ b/tools/Config.mk @@ -861,3 +861,16 @@ LOWERMAP = A a B b C c D d E e F f G g H h I i J j K k L l M m N n O o P p Q q R UPPER_CASE = $(call ULMAP,$(UPPERMAP),$(1)) LOWER_CASE = $(call ULMAP,$(LOWERMAP),$(1)) + +# ZBus iterable sections "zero-touch" mode: supplement the board linker +# script with the zbus sections via INSERT (see include/nuttx/linker/zbus.ld) +# instead of requiring the board script to include common-rom.ld. +# +# The fragment is added through ARCHSCRIPT (not EXTRALINKCMDS) because GNU +# ld requires the INSERT script to come BEFORE the script that defines the +# target section on the command line; this file is included by the board +# Make.defs before it appends its own script, so the fragment lands first. + +ifeq ($(CONFIG_ZBUS_LINKER_INSERT),y) + ARCHSCRIPT += $(TOPDIR)$(DELIM)include$(DELIM)nuttx$(DELIM)linker$(DELIM)zbus.ld +endif