This is the documentation for the latest (main) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

Zephyr 3.4.0

We are pleased to announce the release of Zephyr version 3.4.0.

Major enhancements with this release include:

  • Input subsystem: handles input events from various types of input devices and distributes them to other threads in the application.

  • Barrier API: added architecture agnostic API for data memory barriers.

  • USB Device support:

    • USB device controller API (UDC API) and nRF USBD controller driver.

    • USB device stack implementation using new UDC API.

  • Added Power Delivery Source Support to the USB-C Stack.

  • Bluetooth: Added support for Periodic Advertising with Responses (PAwR).

  • Cache API functions are now fully in-lined by compilers.

  • Added an API for real-time clocks (RTC).

  • Added Retention subsystem.

  • Added initial support for MMU on Xtensa.

  • SMBus (System Management Bus) API.

  • Various improvements to the testing framework and twister:

    • Introduction of 3 new test harnesses into twister supporting pyTest, GoogleTest and Robot Framework.

    • Transitioning to new Ztest API was completed and legacy Ztest was deprecated.

  • Added Snippets: Support common configuration settings that can be used across platforms.

The following sections provide detailed lists of changes by component.

API Changes

Changes in this release

Removed APIs in this release

  • Pinmux API has been removed. Pin control needs to be used as its replacement, refer to Pin Control for more details.

Deprecated in this release

  • Configuring applications with prj_<board>.conf files has been deprecated, this should be replaced by using a prj.conf with the common configuration and board-specific configuration in board Kconfig fragments in the boards folder of the application.

  • On nRF51 and nRF52-based boards, the behavior of the reset reason being provided to sys_reboot() and being set in the GPREGRET register has been dropped. This function will now just reboot the device without changing the register contents. The new method for setting this register uses the boot mode feature of the retention subsystem, see the boot mode API for details. To restore the deprecated functionality, enable CONFIG_NRF_STORE_REBOOT_TYPE_GPREGRET.

  • Deprecated PTHREAD_BARRIER_DEFINE in favor of the standardized pthread_barrier_init()

  • On all STM32 targets except STM32F2 series, Ethernet drivers implementation based on STM32Cube Ethernet API V1 (CONFIG_ETH_STM32_HAL_API_V1) is now deprecated in favor of implementation based on more reliable and performant STM32Cube Ethernet API V2.

  • Legacy Ztest API was deprecated. All new tests shall use the new Ztest API.

Stable API changes in this release

New APIs in this release

Kernel

  • Removed absolute symbols ___cpu_t_SIZEOF, _STRUCT_KERNEL_SIZE, K_THREAD_SIZEOF and _DEVICE_STRUCT_SIZEOF

Architectures

  • ARC

    • Added MPUv8 support

    • Add support of virtual UART over ARC hostlink channel

    • Improved ARCv2 HS4x processors handling - added proper Kconfig options, provided default mcpu

    • Improved ARCMWDT toolchain handling:

      • added rollback to check METAWARE_ROOT if ARCMWDT_TOOLCHAIN_PATH missing

      • reworked extra warnings options handling in twister so it can be used with ARCMWDT

      • used 64bit MDB binary by default

    • Fixed excessive ROM memory consumption if MPU is enabled and ROM & RAM are located in different memory regions

    • Fixed DSP registers handling in case of ARCMWDT

    • Improved SMP handling:

      • Fixed potential livelock in thread abort due to exception

      • Fixed IDU mask setup

    • Removed absolute symbols ___callee_saved_t_SIZEOF and _K_THREAD_NO_FLOAT_SIZEOF

  • ARM

    • Removed absolute symbols ___basic_sf_t_SIZEOF, _K_THREAD_NO_FLOAT_SIZEOF, ___cpu_context_t_SIZEOF and ___thread_stack_info_t_SIZEOF

    • Enabled fp16 for Cortex-M55

    • Fixed a compilation issue with arm-clang and TrustZone

    • Implemented a new cache-management API

    • Added support for generating zImage headers

    • Introduced a new z_arm_on_enter_cpu_idle() hook on CPU idle

  • ARM64

    • Removed absolute symbol ___callee_saved_t_SIZEOF

    • Enabled FPU and FPU_SHARING for v8r aarch64

    • Fixed the STACK_INIT logic during the reset

    • Introduced and enabled safe exception stack

    • Fixed possible deadlock on SMP with FPU sharing

    • Added ISBs after SCTLR Modifications

  • NIOS2

    • Removed absolute symbol _K_THREAD_NO_FLOAT_SIZEOF

  • POSIX:

    • Added Z_SPIN_DELAY to allow to conditionally compile a k_busy_wait() for this arch in tests and samples.

  • RISC-V

    • Added CONFIG_PMP_NO_TOR, CONFIG_PMP_NO_NA4, and CONFIG_PMP_NO_NAPOT to allow disabling unsupported PMP range modes.

    • Removed unused symbols: _thread_offset_to_tp, _thread_offset_to_priv_stack_start, _thread_offset_to_user_sp.

    • Added support for setting PMP granularity with CONFIG_PMP_GRANULARITY.

    • Switched from accessing CSRs from inline assembly to using the csr_read() helper function.

    • Enabled single-threading support.

  • SPARC

    • Removed absolute symbol _K_THREAD_NO_FLOAT_SIZEOF

  • Xtensa

    • Fixed the cross stack call mechanism during nested interrupts where stack would be corrupted under certain conditions.

    • Added initial support for MMU on Xtensa.

    • Now supports building with CONFIG_MULTITHREADING disabled so target can run in single thread only operations.

    • Added C structs to represent interrupt frames to help with debugging.

Bluetooth

  • General

    • Moved all logging symbols together in a new Kconfig.logging file.

    • Deprecated the BT_DEBUG_LOG option. Instead BT_LOG should be used.

    • Made the BT_LOG and BT_LOG_LEGACY options hidden.

    • Removed BT_DEBUG entirely.

  • Audio

    • Implemented the CAP initiator broadcast audio start, stop and metadata update procedures.

    • Implemented the CAP unicast audio start, stop and metadata update procedures.

    • Implemented the Telephony and Media Audio Service (TMAS).

    • Added additional validation for MCC and MCS, including opcodes, values, etc.

    • Refactored and extended the scan delegator implementation, including integration with broadcast sink.

    • Added support for creating a broadcast sink from a PA sink.

    • Added support for optional characteristics in CSIP.

    • Implemented discovery by UUID instead of reading by UUID for multiple characteristics.

    • Added support for long reads and writes for multiple profiles.

    • Added support for long BAP ASE notifications and optimized long notify reads.

    • Offloaded MCS notifications to the system workqueue.

    • Added the CAP initiator cancel procedure.

  • Direction Finding

  • Host

    • Updated the Host to the v5.4 specification.

    • The GATT DB Hash is now recalculated upon loading settings.

    • Added experimental support for SMP keypress notifications.

    • Downgraded the severity of select log messages to avoid log flooding.

    • Separated the handling of LE SC OOB pairing from the legacy OOB logic.

    • Implemented the Encrypted Advertising Data feature.

    • Added support for the new Periodic Advertising with Responses (PAwR), both as an advertiser and as a scanner.

    • Added support for initiating connections from PAwR, as well as receiving connections while synced.

    • Clarified the behavior that is enabled by the BT_PRIVACY Kconfig option.

    • Introduced a new seg_recv L2CAP API for an application to receive segments directly and manage credits explicitly.

  • Mesh

    • Added experimental support for Mesh Protocol d1.1r18 specification, gated by a new configuration option. This includes:

      • Enhanced Provisioning Authentication support.

      • Mesh Remote Provisioning support including:

        • Remote Provisioning Server and Client models.

        • Composition Data Page 128 and Models Metadata Page 128 support.

      • Large Composition Data support including:

        • Large Composition Data Server and Client models.

        • Models Metadata Page 0 support.

      • New Transport Segmentation and Reassembly (SAR) implementation including:

        • SAR Configuration Server and Client models.

      • Mesh Private Beacons support including:

        • Mesh Private Beacon Server and Client models.

      • Opcodes Aggregator support including:

        • Opcodes Aggregator Server and Client models.

      • Proxy Solicitation support including:

        • Solicitation PDU RPL Configuration Server and Client models.

        • On-Demand Private Proxy Server and Client models.

      • Composition Data Page 1 support.

      • Other Mesh Profile Enhancements.

    • Added experimental support for Mesh Binary Large Object Transfer Model d1.0r04_PRr00 specification.

    • Added experimental support for Mesh Device Firmware Update Model d1.0r04_PRr00 specification.

    • Fixed multiple profile errata.

    • Added experimental support for the PSA crypto APIs.

    • Added a new work queue to store mesh settings, including a new API for storing user data.

    • Disabled the models initialization macros for C++ as they use the compound literal feature from C99.

    • Deprecated Health Client and Configuration Client API have been removed.

  • Controller

    • Implemented support for the central with multiple CIS usecase.

    • Implemented support for multiple peripheral CIS establishment.

    • Updated the Controller to the v5.4 specification.

    • Added support for coexistence with other transceivers.

    • Added support for multiple CIS/CIG setup/connect and teardown procedures in sequence.

    • Extended the ticker API to return expiration info.

    • Re-implemented Extended and Periodic Advertising, as well as and Broadcast ISO, using the new ticket expiration info feature.

    • Modified the ticker implementation to reschedule unreserved tickers that use ticks_slot_window. Implement continuous scanning with it.

    • Added support for considering the SDU interval, along with the packet sequence number and time stamps, in SDU fragmentation.

    • Added a new BT_CTRL_TX_PWR_DBM option to set the TX power directly in dBm.

    • Optimized the RX path with support for piggy-backing notifications on already-allocated RX nodes.

  • HCI Driver

Boards & SoC Support

  • Added support for these SoC series:

    • STM32C0 series are now supported (with introduction of STM32C031 SoC).

    • STM32H5 series are now supported (with introduction of STM32H503 and STM32H573 SoCs).

    • Added support for STM32U599 SoC variants

    • Nordic Semiconductor nRF9161

  • Removed support for these SoC series:

  • Made these changes in other SoC series:

  • Added support for these ARC boards:

    • DesignWare ARC HS4x/HS4xD Development Kit (HSDK4xD) - ARCv2 HS47D, SMP 4 cores

    • nsim_hs3x_hostlink - simulation (nSIM-based) platform with hostlink UART

  • Added support for these ARM boards:

    • Aconno ACN52832

    • Alientek STM32L475 Pandora

    • Arduino GIGA R1 Wi-Fi

    • BeagleConnect Freedom

    • Infineon PSoC™ 6 BLE Prototyping Kit (CY8CPROTO-063-BLE)

    • Infineon PSoC™ 6 Wi-Fi BT Prototyping Kit (CY8CPROTO-062-4343W)

    • Infineon XMC4700 Relax Kit

    • MXChip AZ3166 IoT DevKit

    • Nordic Semiconductor nRF9161 DK

    • NXP MIMXRT1040-EVK

    • NXP MIMXRT1062 FMURT6

    • PHYTEC PhyBOARD Polis (NXP i.MX8M Mini)

    • PHYTEC PhyBOARD Pollux (NXP i.MX8M Plus)

    • Raspberry Pi Pico W

    • Raytac MDBT50Q-DB-33

    • Raytac MDBT50Q-DB-40

    • Seeed Studio Wio Terminal

    • Seeed Studio XIAO BLE Sense

    • Silicon Labs BRD2601B

    • Silicon Labs BRD4187C

    • Silicon Labs EFR32 Thunderboard-style boards

    • ST Nucleo C031C6

    • ST Nucleo F042K6

    • ST Nucleo H563ZI

    • ST STM32H573I-DK Discovery

    • Xilinx KV260 (Cortex-R5)

  • Added support for these ARM64 boards:

    • PHYTEC phyCORE-AM62x A53

    • NXP i.MX93 EVK A55 (SOF variant)

  • Added support for these RISC-V boards:

    • Intel FPGA Nios® V/m

    • ITE IT82XX2 EV-Board

  • Added support for these X86 boards:

  • Added support for these Xtensa boards:

    • ESP32S3-DevKitM

  • Made these changes for ARC boards:

    • Added ARC MWDT toolchain support for qemu_arc_hs

    • Improved emsdp platform support:

      • Added DFSS driver support

      • Added pinctrl support

  • Made these changes for ARM boards:

    • atsamc21n_xpro: Enable support to CAN.

    • atsame54_xpro: Read Ethernet MAC from I2C.

    • Changed the default board revision to 0.14.0 for the Nordic boards nrf9160dk_nrf9160 and nrf9160dk_nrf52840. To build for an older revision of the nRF9160 DK without external flash, specify that older board revision when building.

    • nrf9160dk_nrf52840: Enabled external_flash_pins_routing switch by default.

    • nrf9160dk_nrf9160: Changed the order of buttons and switches on the GPIO expander to match the order when using GPIO directly on the nRF9160 SoC.

    • STM32H747i_disco: Enabled support for ST B-LCD40-DSI1 display extension

    • qemu_cortex_m0: Fixed prescaler of the system timer so that its frequency is actually 1 MHz, not 2 MHz.

  • Made these changes for ARM64 boards:

    • FVP revc_2xaemv8a / aemv8r: Added ethernet, PHY and MDIO nodes

  • Made these changes to POSIX boards:

    • nrf52_bsim now includes support and models for:

      • 802.15.4 in the RADIO.

      • EGU.

      • FLASH (NVMC & UICR).

      • TEMP.

      • UART connected to a host ptty.

      • Many more minor CMSIS API and nRF APIs and drivers.

  • Made these changes for RISC-V boards:

    • gd32vf103: No longer requires special OpenOCD version.

  • Made these changes for X86 boards:

  • Made these changes for Xtensa boards:

  • Removed support for these ARC boards:

  • Removed support for these ARM boards:

  • Removed support for these RISC-V boards:

    • BeagleV Starlight JH7100

  • Removed support for these X86 boards:

  • Removed support for these Xtensa boards:

  • Made these changes in other boards:

  • Added support for these following shields:

    • Adafruit Data Logger Shield

    • nPM1300 EK (Power Management Integrated Circuit (PMIC))

    • Panasonic Grid-EYE Shields

    • ST B_LCD40_DSI1_MB1166

Build system and infrastructure

  • Fixed an issue whereby older versions of the Zephyr SDK toolchain were used instead of the latest compatible version.

  • Fixed an issue whereby building an application with sysbuild and specifying mcuboot’s verification to be checksum only did not build a bootable image.

  • Fixed an issue whereby if no prj.conf file was present then board configuration files would not be included by emitting a fatal error. As a result, prj.conf files are now mandatory in projects.

  • Introduced support for extending/replacing the signing mechanism in zephyr, see West extending signing for further details.

  • Fixed an issue whereby when using *_ROOT variables with Sysbuild, these were lost for images.

  • Enhanced zephyr_get CMake helper function to optionally support merging of scoped variables into a list.

  • Added a new CMake helper function for setting/updating sysbuild CMake cache variables: sysbuild_cache_set.

  • Enhanced zephyr_get CMake helper function to lookup multiple variables and return the result in a variable of different name.

  • Introduced EXTRA_CONF_FILE, EXTRA_DTC_OVERLAY_FILE, and EXTRA_ZEPHYR_MODULES for better naming consistency and uniform behavior for applying extra build settings in addition to Zephyr automatic build setting lookup. EXTRA_CONF_FILE replaces OVERLAY_CONFIG. EXTRA_ZEPHYR_MODULES replaces ZEPHYR_EXTRA_MODULES. EXTRA_DTC_OVERLAY_FILE is new, see Set devicetree overlays for further details.

  • Twister now supports gtest harness for running tests written in gTest.

  • Added an option to validate device initialization priorities at build time. To use it, enable CONFIG_CHECK_INIT_PRIORITIES, see scripts/build/check_init_priorities.py for more details.

  • Added a new option to disable tracking of macro expansion when compiling, CONFIG_COMPILER_TRACK_MACRO_EXPANSION. This option may be disabled to reduce compiler verbosity when errors occur during macro expansions, e.g. in device definition macros.

  • Twister now supports loading test configurations from alternative root folder/s by using --alt-config-root. When a test is found, Twister will check if a test configuration file exist in any of the alternative test configuration root folders. For example, given $test_root/tests/foo/testcase.yaml, Twister will use $alt_config_root/tests/foo/testcase.yaml if it exists.

  • Twister now uses native YAML lists for fields that were previously defined using space-separated strings. For example:

    platform_allow: foo bar

    can now be written as:

    platform_allow:
  - foo
  - bar

    This applies to the following properties:

    • arch_exclude

    • arch_allow

    • depends_on

    • extra_args

    • extra_sections

    • platform_exclude

    • platform_allow

    • tags

    • toolchain_exclude

    • toolchain_allow

    Note that the old behavior is kept as deprecated. The scripts/utils/twister_to_list.py script can be used to automatically migrate Twister configuration files.

  • When MCUboot image signing is enabled, a warning will now be emitted by cmake if no signing key is set in the project, this warning can be safely ignored if signing is performed manually or outside of zephyr. This warning informs the user that the generated image will not be bootable by MCUboot as-is.

  • Babblesim is now included in the west manifest. Users can fetch it by enabling the babblesim group with west config.

  • west sign now uses DT labels, of “fixed-partition” compatible nodes, to identify application image slots, instead of previously used DT node label properties. If you have been using custom partition layout for MCUboot, you will have to label your MCUboot slot partitions with proper DT node labels; for example partition with “image-0” label property will have to be given slot0_partition DT node label. Label property does not have to be removed from partition node, but will not be used.

    DT node labels used are listed below

    Partition with label property

    Required DT node label

    “image-0”

    slot0_partition

    “image-1”

    slot1_partition

  • Fixed an issue whereby relative paths supplied for the BOARD_ROOT value might wrongly emit a warning about a boards directory not being found.

  • Fixed an issue whereby relative paths did not work for sysbuild images.

Drivers and Sensors

  • Device model

    • Devices that do not require an initialization routine can now pass NULL to the DEVICE_*_DEFINE() macros.

  • Auxiliary display

    • New auxiliary display (auxdisplay) peripheral has been added, this allows for interfacing with simple alphanumeric displays that do not feature graphic capabilities. This peripheral is marked as unstable.

    • HD44780 driver added.

    • Noritake Itron driver added.

    • Grove LCD driver added (ported from existing sample).

  • ADC

    • MCUX LPADC driver now uses the channel parameter to select a software channel configuration buffer. Use zephyr,input-positive and zephyr,input-negative devicetree properties to select the hardware channel(s) to link a software channel configuration to.

    • MCUX LPADC driver voltage-ref and power-level devicetree properties were shifted to match the hardware as described in reference manual instead of matching the NXP SDK enum identifiers.

    • Added support for STM32C0 and STM32H5.

    • Added DMA support for STM32H7.

    • STM32: Resolutions are now listed in the device tree for each ADC instance

    • STM32: Sampling times are now listed in the device tree for each ADC instance

    • Added driver for Atmel SAM family ADC.

    • Added driver for Gecko Incremental ADC.

    • Added driver for Infineon CAT1 ADC.

    • Added driver for TI ADS7052.

    • Added driver for TI ADS114S0x family.

    • Added drivers for Renesas SmartBond GPADC and SDADC.

  • Battery-backed RAM

    • Added MCP7940N battery-backed RTC SRAM driver.

  • CAN

    • The CAN statistics are now reset when calling can_start().

    • Renamed the NXP FlexCAN devicetree binding compatible from nxp,kinetis-flexcan to nxp,flexcan.

    • Added support for the CAN-FD variant of the NXP FlexCAN controller using devicetree binding nxp,flexcan-fd.

    • Added support for the NXP NXP S32 CANEXCEL controller using devicetree binding nxp,s32-canxl.

    • Added support for the Atmel SAM0 CAN controller using devicetree binding atmel,sam0-can.

    • Refactored the Bosch M_CAN controller driver backend to allow for per-instance configuration via devicetree.

    • Now supports STM32H5 series.

  • Clock control

    • Atmel SAM/SAM0: Introduced peripheral clock control.

    • Atmel SAM0: Improved samd20/samd21/samr21 clocking mechanism.

    • STM32F4: Added support for PLL I2S

  • Console:

    • The native_posix and bsim console drivers have been merged into one generic driver usable by all POSIX arch based boards.

  • Counter

    • Added support on timer based counter on STM32H7 and STM32H5

    • Added support on RTC based counter on STM32C0 and STM32H5

  • Crypto

    • Added support for STM32H5 AES

  • DAC

    • Added support on STM32H5 series.

  • Disk

    • SDMMC STM32L4+: Now compatible with internal DMA

    • NVME disks are now supported using FATFS, with a single I/O queue enabled

  • Display

    • Improved MCUX ELCDIF and SSD16XX display controller drivers

    • Added support for ILI9342C display controller

    • Added support for OTM8009A panel

  • DMA

    • STM32C0: Added support for DMA

    • STM32H5: Added support for GPDMA

    • STM32H7: Added support for BDMA

    • Added DMA support for the RP2040 SoC

  • EEPROM

  • Entropy

    • Added support for STM32H5 series.

  • Flash

    • Introduced new flash API call flash_ex_op() which calls ec_op() callback provided by a flash driver. This allows to perform extra operations on flash devices, defined by Zephyr Flash API or by vendor specific header files. CONFIG_FLASH_HAS_EX_OP should be selected by the driver to indicate that extra operations are supported. To enable extra operations user should select CONFIG_FLASH_EX_OP_ENABLED.

    • STM32F4: Now supports write protection and readout protection through new flash API call flash_ex_op().

    • nrf_qspi_nor: Replaced custom API function nrf_qspi_nor_base_clock_div_force with nrf_qspi_nor_xip_enable which apart from forcing the clock divider prevents the driver from deactivating the QSPI peripheral so that the XIP operation is actually possible.

    • flash_simulator:

      • A memory region can now be used as the storage area for the flash simulator. Using the memory region allows the flash simulator to keep its contents over a device reboot.

      • When building in native_posix, command line options have been added to select if the flash should be cleared at boot, the flash content kept in RAM, or the flash content file be deleted on exit.

    • spi_flash_at45: Fixed erase procedure to properly handle chips that have their initial sector split into two parts (usually marked as 0a and 0b).

    • STM32H5 now supports OSPI

  • GPIO

    • Converted the gpio_keys driver to the input subsystem.

    • Added single-ended IO support for the RP2040 SoC

    • STM32: Supports newly introduced experimental API to enable/disable interrupts without re-config

  • I2C

    • Added support for STM32C0 and STM32H5 series

  • I2S

    • STM32: Domain clock should now be configured by device tree.

  • Input

    • Introduced the Input subsystem.

  • KSCAN

    • Added a zephyr,kscan-input input to kscan compatibility driver.

    • Converted the ft5336 and kscan_sdl drivers to the input subsystem.

  • MIPI-DSI

    • Added support on STM32H7

  • Misc

    • Added PIO support for the RP2040 SoC

  • PCIE

    • Enable filtering PCIe devices by class/revision.

  • PECI

  • Retained memory

    • Retained memory (retained_mem) driver has been added with backends for Nordic nRF GPREGRET, and uninitialised RAM.

  • Pin control

    • Added support for Infineon CAT1

    • Added support for TI K3

    • Added support for ARC emdsp

  • PWM

    • Added support for STM32C0.

    • STM32: Now supports 6-PWM channels

    • Added PWM driver for Microchip XEC BBLED.

  • Power domain

  • Regulators

    • The regulator API can now be built without thread-safe reference counting by using CONFIG_REGULATOR_THREAD_SAFE_REFCNT. This feature can be useful in applications that do not enable CONFIG_MULTITHREADING.

    • Added support for ADP5360 PMIC

    • Added support for nPM1300 PMIC

    • Added support for Raspberry Pi Pico core supply regulator

  • SDHC

    • Support was added for using CPOL/CPHA SPI clock modes with SD cards, as some cards require the SPI clock switch to low when not active

  • Sensor

    • Added generic voltage measurement sample

    • Removed STM32 Vbat measurement sample (replaced by a generic one)

    • Added STM32 Vref sensor driver

    • Added STM32 Vref/Vbat measurement through the new generic voltage measurement sample

    • Added temperature measurement driver for STM32C0 and STM32F0x0

    • Removed STM32 temperature measurement sample (replaced by a generic one)

    • Added STM32 temperature measurement through the generic temperature measurement sample

  • Serial

    • Added UART3 and UART4 configuration for gd32vf103 SoCs.

    • uart_altera: added new driver for Altera Avalon UART.

    • uart_emul: added new driver for emulated UART.

    • uart_esp32: * Added support for ESP32S3 SoC. * Added support for RS-485 half duplex mode.

    • uart_hostlink: added new driver for virtual UART via Synopsys ARC hostlink channels.

    • uart_ifx_cat1: added new driver for Infineon CAT1 UART.

    • uart_mcux: added power management support.

    • uart_mcux_flexcomm: added support for asynchronous operations.

    • uart_mcux_lpuart: added support for parity.

    • uart_ns16550: now supports per instance hardware access mode instead of one access mode for all instances.

    • uart_pl011: fixed interrupt support.

    • uart_rpi_pico_pio: added new driver to support UART via Programmable Input/Output (PIO) on Raspberry Pi Pico.

    • uart_xmc4xxx: added support for asynchronous operations.

    • uart_stm32: Now support driver enable mode

    • Added hardware flow control support for the RP2040 SoC

  • SPI

    • Added support on STM32H5 series.

  • Timer

    • Support added for stopping Nordic nRF RTC system timer, which fixes an issue when booting applications built in prior version of Zephyr.

    • STM32: Now supports a prescaler at the input of clock (default not divided). Prescaler allows to achieve higher LPTIM timeout (up to 256s when lptim clocked by LSE) and consequently higher core sleep durations but impacts the tick precision. To be used with caution.

  • USB

    • Added remote wakeup support for the RP2040 SoC

    • Added Battery Charging (BC12) API and PI3USB9201 driver implementation.

    • Added new USB device controller drivers (using usb_dc API) for ITE IT82xx2 and smartbond platforms.

    • Added USB device controller driver skeleton for UDC API.

    • Reworked DWC2 driver and added support for STM32F4 SoC family

  • W1

  • Watchdog

    • Added support for STM32C0 and STM32H5 series

Networking

  • CoAP:

  • Connection Manager:

    • Extended the library with a generic L2 connectivity API.

    • Refactored library internals significantly.

    • Improved thread safety in the library.

    • Reworked how Connection Manager events are notified - they are no longer raised for each interface individually, but instead:

      • NET_EVENT_L4_CONNECTED is called only once after the first interface gains connectivity.

      • NET_EVENT_L4_DISCONNECTED is called only after connectivity is lost on all interfaces.

    • Improved Connection Manager test coverage.

  • DHCPv4:

    • Fixed a potential packet leak in DHCPv4 input handler.

    • Fixed a potential NULL pointer dereference in dhcpv4_create_message().

    • Added a mechanism to register a callback for handling DHCPv4 options.

    • Modified dhcpv4_client sample to trigger DHCP on all network interfaces in the system.

  • DNS:

    • Fixed a possible crash on NULL pointer as a query callback.

    • Added a check on existing DNS servers before reconfigure.

    • Improved debug logging in DNS SD.

    • Fixed IPv4/IPv6 address handling in mDNS responder, if both are IPv4 and IPv6 are enabled.

    • Removed dead code in DNS SD query parsing.

  • Ethernet:

    • Fixed double packet dereference in case of ARP request transmission errors.

    • Fixed a possible slist corruption in case Ethernet interface went up before LLDP initialization.

  • HTTP:

    • Added HTTP service and resource iterable sections.

  • ICMPv6:

    • Implemented IPv6 RA Recursive DNS Server option handling.

  • IEEE802154:

    • Fixed a corner case with 6LoWPAN IP Header Compression and fragmentation, where for a short range of packet sizes, fragmentation did not work correctly after IPHC.

    • Added new radio API function to start continuous carrier wave transmission.

    • Several improvements/fixes in IEEE802154 L2 security.

    • Fixed a packet leak when handling beacon/command frames.

    • Deprecated CONFIG_IEEE802154_2015 Kconfig option.

    • Added simple Babblesim echo test over IEEE802154 L2.

    • Improved IEEE802154 L2 test coverage.

    • Multiple other minor IEEE802154 L2 and documentation improvements/fixes.

  • IPv4:

    • Implemented a fallback to IPv4 Link Local address if no other address is available.

    • Fixed net_ipv4_is_ll_addr() helper function to correctly identify LL address.

    • Fixed possible NULL pointer dereference in IPv4 fragmentation.

  • LwM2M:

    • Added new LWM2M_RD_CLIENT_EVENT_REG_UPDATE event.

    • Added missing const qualifier in the APIs, where applicable.

    • Fixed socket error handling on packet transmission.

    • Improved LwM2M context cleanup when falling back to regular Registration.

    • Added possibility to register a callback function for FW update cancel action.

    • Added possibility to register a callback function for LwM2M send operation.

    • Added ISPO voltage sensor object support.

    • Fixed stopping of the LwM2M client when it’s suspended.

    • Fixed a minor CoAP RFC incompatibility, where it should not be assumed that consecutive data blocks in block transfer will carry the same token.

    • Added block transfer support on TX.

    • Fixed a possible out-of-bounds memory access when creating FW update object.

    • Added possibility to override default socket option configuration with a dedicated callback function (set_socketoptions).

    • Improved LwM2M test coverage.

    • Several other minor improvements and cleanups.

  • Misc:

    • Added generic OFFLOADED_NETDEV_L2 for offloaded devices to allow offloaded implementations to detect when interface is brought up/down.

    • Factored out net_buf_simple routines to a separate source file.

    • Fixed possible NULL pointer dereference in net_pkt_cursor_operate().

    • Reimplemented net_mgmt to use message queue internally. This also fixed a possible event loss with the old implementation.

    • Fixed error handling in net ping shell command to avoid shell freeze.

    • Improved Ethernet error statistics logging in net stats shell command.

    • Moved SLIP TAP implementation into a separate file, to prevent build warnings about missing sources for Ethernet drivers.

    • Fixed crashes in echo_server and echo_client samples, when userspace is enabled.

    • Fixed IPv6 support in mqtt_sn_publisher sample.

    • Fixed build issues with arm-clang in the networking stack.

    • Added new NET_IF_IPV6_NO_ND and NET_IF_IPV6_NO_MLD interface flags, which allow to disable ND/MLD respectively on an interface.

    • Reworked network interface mutex protection, to use individual mutex for each interface, instead of a global one.

    • Added new AWS IoT Core MQTT.

    • Added a few missing NULL pointer checks in network interface functions.

  • OpenThread:

    • Implemented the following OpenThread platform APIs:

      • otPlatRadioSetMacFrameCounterIfLarger(),

      • otPlatCryptoEcdsaGenerateAndImportKey(),

      • otPlatCryptoEcdsaExportPublicKey(),

      • otPlatCryptoEcdsaVerifyUsingKeyRef(),

      • otPlatCryptoEcdsaSignUsingKeyRef().

    • Added CONFIG_OPENTHREAD_CSL_TIMEOUT option.

    • Removed no longer needed CONFIG_OPENTHREAD_EXCLUDE_TCPLP_LIB.

    • Added simple Babblesim echo test over OpenThread.

  • SNTP:

    • Switched to use zsock_* functions internally.

  • Sockets:

    • Fixed SO_RCVBUF and SO_SNDBUF socket options handling, so that they configure TCP window sizes correctly.

    • Fixed SO_SNDTIMEO socket option handling - the timeout value was ignored and socket behaved as in non-blocking mode when used.

    • Reworked TLS sockets implementation, to allow parallel TX/RX from different threads.

    • Implemented TLS handshake timeout.

    • Added support for asynchronous connect for TCP sockets.

    • Fixed blocking recv() not being interrupted on socket close.

    • Fixed blocking accept() not being interrupted on socket close.

    • Improved sockets test coverage.

  • TCP:

    • Fixed incorrect TCP stats by improving packet processing result reporting.

    • Added CONFIG_NET_TCP_PKT_ALLOC_TIMEOUT to allow to configure packet allocation timeout.

    • Improved TCP test coverage.

    • Fixed TCP MSS calculation for IPv6.

    • Fixed possible double acknowledgment of retransmitted data.

    • Fixed local address setting for incoming connections.

    • Fixed double TCP context dereferencing in certain corner cases.

  • TFTP:

    • Added tftp_put() API to support TFTP write request.

    • Introduced tftp_callback_t callback to allow to read large files.

    • Reworked struct tftpc client context structure, to allow for parallel communication from several contexts.

  • UDP:

  • Websockets:

    • Implemented proper timeout handling in websocket_recv_msg().

    • Fixed implicit type conversion when parsing length field, which could lead to data loss.

  • Wi-Fi:

    • Display TWT (Target Wake Time) configuration response status in Wi-Fi shell.

    • Added more detailed TWT response parameters printout in Wi-Fi shell.

    • Added new NET_EVENT_WIFI_TWT_SLEEP_STATE event to notify TWT sleep status.

    • Fixed an issue where not all security modes were displayed correctly on scan.

    • Added connection status and AP capabilities verification before initiating TWT operation.

    • TWT intervals are changed from milliseconds to microseconds, interval variables are also renamed.

    • Extended Power Saving configuration parameters with listening interval and wake up mode.

    • Added CONFIG_WIFI_MGMT_RAW_SCAN_RESULTS option, which enables providing of RAW (unprocessed) scan results to the application with NET_EVENT_WIFI_CMD_RAW_SCAN_RESULT event.

    • Several other minor fixes/cleanups in the Wi-Fi management/shell modules.

  • zperf

    • Added an extra parameter to disable Nagle’s algorithm with TCP benchmarks.

    • Added support for handling multiple incoming TCP sessions.

    • Made zperf thread priority and stack size configurable.

    • Several minor cleanups in the module.

USB

  • USB device support

    • Fixed control endpoint handling with MPS of 8 bytes.

  • New experimental USB support

    • Various improvements for new device support, better string descriptor support, implemented usbd_class_shutdown API.

    • Added USB Mass Storage class and CDC ECM class implementations for the new device support.

Libraries / Subsystems

  • File systems

    • Added CONFIG_FS_FATFS_REENTRANT to enable the FAT FS reentrant option.

    • With LittleFS as backend, fs_mount() return code was corrected to EFAULT when called with FS_MOUNT_FLAG_NO_FORMAT and the designated LittleFS area could not be mounted because it has not yet been mounted or it required reformatting.

    • The FAT FS initialization order has been updated to match LittleFS, fixing an issue where attempting to mount the disk in a global function caused FAT FS to fail due to not being registered beforehand. FAT FS is now initialized in POST_KERNEL.

    • Added CONFIG_FS_LITTLEFS_FMP_DEV to enable possibility of using LittleFS for block devices only, e.g. without Flash support. The option is set to ‘y’ by default in order to keep previous behaviour.

  • IPC

    • ipc_service_close_instance() now only acts on bounded endpoints.

    • ICMSG: removed race condition during bonding.

    • ICMSG: removed internal API for clearing shared memory.

    • ICMSG: added mutual exclusion access to SHMEM.

    • Fixed CONFIG_OPENAMP_WITH_DCACHE.

  • Management

    • Added optional input expiration to shell MCUmgr transport, this allows returning the shell to normal operation if a complete MCUmgr packet is not received in a specific duration. Can be enabled with CONFIG_MCUMGR_TRANSPORT_SHELL_INPUT_TIMEOUT and timeout set with CONFIG_MCUMGR_TRANSPORT_SHELL_INPUT_TIMEOUT_TIME.

    • MCUmgr fs_mgmt upload and download now caches the file handle to improve throughput when transferring data, the file is no longer opened and closed for each part of a transfer. In addition, new functionality has been added that will allow closing file handles of uploaded/downloaded files if they are idle for a period of time, the timeout is set with MCUMGR_GRP_FS_FILE_AUTOMATIC_IDLE_CLOSE_TIME. There is a new command that can be used to close open file handles which can be used after a file upload is complete to ensure that the file handle is closed correctly, allowing other transports or other parts of the application code to use it.

    • A new version of the SMP protocol used by MCUmgr has been introduced in the header, which is used to indicate the version of the protocol being used. This updated protocol allows returning much more detailed error responses per group, see the MCUmgr SMP protocol specification for details.

    • MCUmgr has now been marked as a stable Zephyr API.

    • The MCUmgr UDP transport has been refactored to resolve some concurrency issues and fixes a potential issue whereby an application might call the open transport function whilst it is already open, causing an endless log output loop.

    • The MCUmgr fs_mgmt group Kconfig Insecure text has been replaced with a CMake warning which triggers if fs_mgmt hooks are not enabled, as these hooks can be used to ensure security of file access allowed by MCUmgr clients.

    • Fixed an issue with MCUmgr fs_mgmt file download not checking if the offset parameter was provided.

    • Fixed an issue with MCUmgr fs_mgmt file upload notification hook not setting upload to true.

    • Fixed an issue with MCUmgr img_mgmt image upload upgrade field wrongly checking if the new image was the same version of the application and allowing it to be uploaded if it was.

    • MCUmgr img_mgmt group will only verify the SHA256 hash provided by the client against the uploaded image (if support is enabled) if a full SHA256 hash was provided.

    • MCUmgr Kconfig options have changed from select to depends on which means that some additional Kconfig options may now need to be selected by applications. CONFIG_NET_BUF, CONFIG_ZCBOR and CONFIG_CRC are needed to enable MCUmgr support, CONFIG_BASE64 is needed to enable shell/UART/dummy MCUmgr transports, CONFIG_NET_SOCKETS is needed to enable the UDP MCUmgr transport, CONFIG_FLASH is needed to enable MCUmgr fs_mgmt, CONFIG_FLASH and CONFIG_IMG_MANAGER are needed to enable MCUmgr img_mgmt.

    • MCUmgr img_mgmt group now uses unsigned integer values for image and slot numbers, these numbers would never have been negative and should have been unsigned.

  • POSIX API

    • Improved the locking strategy for eventfd_read() and eventfd_write(). This eliminated a deadlock scenario that was present since the initial contribution and increased performance by a factor of 10x.

    • Reimplemented POSIX threads, mutexes, condition variables, and barriers using native Zephyr counterparts. POSIX synchronization primitives in Zephyr were originally implemented separately and received less maintenance as a result. Unfortunately, this opened POSIX up to unique bugs and race conditions. Going forward, POSIX will benefit from all improvements to Zephyr’s synchronization and threading API and race conditions have been mitigated.

  • Retention

    • Retention subsystem has been added which adds enhanced features over retained memory drivers allowing for partitioning, magic headers and checksum validation. See retention API for details. Support for the retention subsystem is experimental.

    • Boot mode retention module has been added which allows for setting/checking the boot mode of an application, initial support has also been added to MCUboot to allow for applications to use this as an entrance method for MCUboot serial recovery mode. See boot mode API for details.

  • RTIO

    • Added policy that every sqe will generate a cqe (previously an RTIO_SQE_TRANSACTION entry would only trigger a cqe on the last sqe in the transaction.

  • Power management

    • Added a new policy event API that can be used to register expected events that will wake the system up in the future. This can be used to influence the system on which low power states can be used.

    • Added a new device tree property zephyr,pm-device-runtime-auto to automatically enable device runtime power management on a device after its initialization.

HALs

  • Nordic

    • Updated nrfx to version 3.0.0.

  • STM32

    • stm32cube: updated STM32F0 to cube version V1.11.4.

    • stm32cube: updated STM32F3 to cube version V1.11.4

    • stm32cube: updated STM32L0 to cube version V1.12.2

    • stm32cube: updated STM32U5 to cube version V1.2.0

    • stm32cube: updated STM32WB to cube version V1.16.0

  • Raspberry Pi Pico

    • Updated hal_rpi_pico to version 1.5.0

MCUboot

  • Relocated the MCUboot Kconfig options from the main Kconfig.zephyr file to a new modules/Kconfig.mcuboot module-specific file. This means that, for interactive Kconfig interfaces, the MCUboot options will now be located under Modules instead of under Boot Options.

  • Added CONFIG_MCUBOOT_CMAKE_WEST_SIGN_PARAMS that allows to pass arguments to west sign when invoked from cmake.

Storage

  • Added CONFIG_FLASH_MAP_LABELS, which will enable runtime access to the labels property of fixed partitions. This option is implied if kconfig:option:CONFIG_FLASH_MAP_SHELL is enabled. These labels will be displayed in a separate column when using the flash_map list shell command.

Trusted Firmware-M

  • Enable routing of PSA Crypto API calls from NS to S, thanks to separating MbedTLS into three distinct libraries at build time (crypto, TLS, X.509). This also resolves header conflicts with earlier integrations of TF-M and MbedTLS.

  • Added psa_crypto sample back.

zcbor

Updated from 0.6.0 to 0.7.0. Among other things, this update brings:

  • C++ improvements

  • float16 support

  • Improved docs

  • -Wall and -Wconversion compliance

Tests and Samples

  • Two Babblesim based networking (802.15.4) tests have been added, which are run in Zephyr’s CI system. One of them including the OpenThread stack.

  • For native_posix and the nrf52_bsim: Many tests have been fixed and enabled.

  • LittleFS sample has been given SPI example configuration for nrf52840dk_nrf52840.

  • Migrated all tests to new Ztest API and deprecated legacy Ztest.