We are pleased to announce the release of Zephyr RTOS version 2.3.0.
Major enhancements with this release include:
A new Zephyr CMake package has been introduced, reducing the need for environment variables
A new Devicetree API, based on hierarchical macros, has been introduced. This new API allows the C code to access virtually all nodes and properties in a clean, organized fashion
The kernel timeout API has been overhauled to be flexible and configurable, with future support for features like 64-bit and absolute timeouts in mind
A new k_heap/sys_heap heap allocator has been introduced, with much better performance than the existing k_mem_pool/sys_mem_pool
Zephyr now integrates with the TF-M (Trusted Firmware M) PSA-compliant framework
The Bluetooth Low Energy Host now supports LE Advertising Extensions
The CMSIS-DSP library is now included and integrated
The following sections provide detailed lists of changes by component.
You can check all currently known issues by listing them using the GitHub interface and listing all issues with the bug label.
A single high-priority bug is currently open:
23364 - Bluetooth: bt_recv deadlock on supervision timeout with pending GATT Write Commands
The identifier data structure for hwinfo drivers is clarified. Drivers are responsible for ensuring that the identifier data structure is a sequence of bytes. The returned ID value is not supposed to be interpreted based on vendor-specific assumptions of byte order and should express the identifier as a raw byte sequence. The changes have an impact on users that use the hwinfo API to identify their devices. The sam0 driver byte swaps each 32 bit word of the 128 bit identifier to big endian. The nordic driver byte swaps the entire 64 bit word to big endian.
Added a new API for recovering an I2C bus from situations where the I2C master and one or more I2C slaves are out of synchronization (e.g. if the I2C master was reset in the middle of an I2C transaction or if a noise pulse was induced on the SCL line).
Deprecated in this release¶
k_uptime_delta_32(), use k_uptime_delta()
All timeout values are now encapsulated k_timeout_t opaque structure when passing them to the kernel. If you want to revert to the previous s32_t type for the timeout parameter, please enable
BT_LE_SCAN_FILTER_DUPLICATE, use BT_LE_SCAN_OPT_FILTER_DUPLICATE instead
BT_LE_SCAN_FILTER_WHITELIST, use BT_LE_SCAN_OPT_FILTER_WHITELIST instead
bt_le_scan_param::filter_dup, use bt_le_scan_param::options instead
bt_conn_create_le(), use bt_conn_le_create() instead
bt_conn_create_auto_le(), use bt_conn_le_create_auto() instead
bt_conn_create_slave_le(), use bt_le_adv_start() instead with bt_le_adv_param::peer set to the remote peers address.
BT_LE_ADV_* macros, use BT_GAP_ADV_* enums instead
nrf51_pca10028 has been renamed to nrf51dk_nrf51422
nrf51_pca10031 has been renamed to nrf51dongle_nrf51422
nrf52810_pca10040 has been renamed to nrf52dk_nrf52810
nrf52_pca10040 has been renamed to nrf52dk_nrf52832
nrf52833_pca10100 has been renamed to nrf52833dk_nrf52833
nrf52811_pca10056 has been renamed to nrf52840dk_nrf52811
nrf52840_pca10056 has been renamed to nrf52840dk_nrf52840
nrf52840_pca10059 has been renamed to nrf52840dongle_nrf52840
nrf9160_pca10090 has been renamed to nrf9160dk_nrf9160
nrf52840_pca10090 has been renamed to nrf9160dk_nrf52840
nrf52_pca20020 has been renamed to thingy52_nrf52832
nrf5340_dk_nrf5340 has been renamed to nrf5340pdk_nrf5340
efr32_slwstk6061a has been renamed to efr32_radio_brd4250b
The C macros generated from the devicetree in previous releases are now deprecated in favor of a new
Use of the legacy macros now requires explicitly enabling
CONFIG_LEGACY_DEVICETREE_MACROS. See the Zephyr v2.3 legacy devicetree macro page for more information, including a link to a migration guide to the new API.
MACRO_MAPhas been deprecated. Use
BUILD_ASSERT_MSGhas been deprecated. Use
Removed APIs in this release¶
util.hhas been removed.
stack_unused_space_gethave been removed.
Stable API changes in this release¶
The net_idx parameter has been removed from the Health Client model APIs since it can be derived (by the stack) from the app_idx parameter
The NET_DEVICE_INIT(), NET_DEVICE_INIT_INSTANCE(), NET_DEVICE_OFFLOAD_INIT() and ETH_NET_DEVICE_INIT() macros changed and take a device power management function pointer parameter. If networking PM is not implemented for the specific network device, the device_pm_control_nop value can be used.
The video_dequeue() API call now takes a k_timeout_t for the timeout parameter. This reverts to s32_t if CONFIG_LEGACY_TIMEOUT_API is enabled.
Floating Point Services
FLOAT and FP_SHARING Kconfig options have been renamed to FPU and FPU_SHARING, respectively.
A new general purpose memory allocator, sys_heap/k_heap, has been added to Zephyr with more conventional API/behavior, better space efficiency and higher performance than the pre-existing mem_pool. The older mem_pool APIs are, by default, wrappers around this new heap backend and will be deprecated in an upcoming release. The original implementation remains available for this release via disabling CONFIG_MEM_POOL_HEAP_BACKEND.
The timeout arguments to all kernel calls are now a “k_timeout_t” type instead of a 32 bit millisecond count. These can be initialized in arbitrary time units (ns/us/ms, ticks), be interpreted relative to either current time or system start, and be expressed in 64 bit quantities. This involves a minor change to the API, so the original API is still available in a completely source-compatible way via CONFIG_LEGACY_TIMEOUT_API.
Simplified dummy thread implementation and properly name idle threads
Centralized new thread priority check
Refactored device structures and introduced struct init_entry which is a generic init end-point. SYS_INIT() generates only a struct init_entry via calling INIT_ENTRY_DEFINE(). Also removed struct deviceconfig leaving struct device to own everything now.
Changed to automatic generation of privilege stack for ARC MPU V2 to avoid the potential waste of memory When USERSPACE is configured
Enhanced runtime programming for the MPU v3 by making the gap-filling of kernel memory a user-configurable feature
Refactored the thread switch code in epilogue of irq and exception
Refactored the assembly codes for better maintenance
Fixed the behavior of ARC timer driver
Fixed the behavior of ARC SMP
Fixed the wrong configurations of ARC boards in Kconfig and DTS
CMSIS has been moved out of the main tree and now resides in its own standalone module repository
Updated CMSIS version to 5.7.0
Added CMSIS-DSP library integration
Added semihosting console support
Cleanups and improvements to the Cortex-M exception vector table
Fixed the behavior of Cortex-M spurious IRQ handler
Fixed parsing of Cortex-M MemManage Stacking Errors
Fixed the arch_cpu_idle() implementation for Cortex-M and Cortex-R
Renamed Cortex-R architecture port to cortex_a_r in preparation for the AArch32 Cortex-A architecture port
Added processor exception handling and reporting framework for Cortex-R
Added nested interrupt support on AArch32 Cortex-R and AArch64 Cortex-A
Refactored Cortex-R interrupt system to remove fake multi-level interrupt controller abstraction scheme
Added support for building on ARM hosts
Added support for hard floating point for RISC-V
Added march and mabi options to Kconfig
Fixed compilation warning for platforms without PLIC
Instrumented code for timing information
Added ability for SoC to add MMU regions
x86 FPU sharing symbols renamed
early_serial: extended to support MMIO UART
Boards & SoC Support¶
Added support for these SoC series:
Broadcom Viper BCM58402
Infineon XMC4500 SoC
Nordic nRF52820 SoC
NXP LPC55S16 SoC
SiLabs EFR32BG13P SoC
STM32L5 series of Ultra-low-power MCUs
Added support for these ARM boards:
96Boards AeroCore 2
Adafruit Feather nRF52840 Express
Adafruit Feather STM32F405 Express
Black STM32 F407VE Development Board
Black STM32 F407ZG Pro Development Board
EFR32 BRD4104A (SLWRB4104A)
nRF52820 emulation on nRF52833 DK
SEGGER IP Switch Board
ST Nucleo H743ZI
ST Nucleo F303RE
ST Nucleo L552ZE-Q
Made these changes in other boards
up_squarednow defaults to the x86_64 architecture
intel_s1000now supports SMP
Added support for these following shields:
Espressif ESP-8266 Module
MikroElektronika ADC Click
MikroElectronica Eth Click
ST X-NUCLEO-IKS02A1: MEMS Inertial and Environmental Multi sensor shield
Drivers and Sensors¶
Added support for STM32G4, STM32L1 and STM32H7 series
Enabled internal voltage reference source on stm32
Added Microchip MCP320x driver
Added an RX thread on stm32wb hci wrapper
Improved BLE support for rv32m1_vega:
Added Resolvable Private Address support
Enabled power saving support
Added 2 Mbps PHY support
Enabled controller-based privacy
Converted can-primary alias to zephyr,can-primary chosen property
Converted loopback driver to use a thread to send frames
Enabled MSI range config in PLL mode on stm32
Fixed AHB clock computation based on core on stm32h7
Fixed USB initialization
Added semihosting console
Added support on stm32h7 and stm32l0
Fixed alarm tick count on stm32
Added Maxim DS3231 driver
Added NXP Kinetis LPTMR driver
Added driver for nRF ECB
Added CAP_NO_IV_PREFIX capability to stm32 driver
Added stm32l0 series support
Added DAC shell
Added NXP Kinetis DAC and DAC32 drivers
Added power management support to st7789v driver
Reworked controller memory initialization in ssd16xx driver
Updated st7789v driver to set x-offset and y-offset properties properly
Enabled use of DMAMUX on stm32l4+ and stm32wb
Various fixes on stm32 dma management
Removed Kconfig HAS_DTS_ENTROPY
Implemented ISR specific get entropy call in gecko driver
Various fixes in Microchip driver
Added SAM E54 max queue count referencing
Added SAM0 family support to gmac driver
Added sam4e support to queue in gmac
Added network power management support to mcux
Added VLAN support to enc28j60
Added VLAN support to stm32
Added Ethernet cable link status support to gmac
Added support for i.MXRT1060 family to mcux
Added support for getting manual MAC address from devicetree
Added support for enabling random MAC address from devicetree
Various fixes to setup and cache handling in gmac
Fixed how unique MAC address is determined in mcux
Fixed Ethernet cable link detection in gecko
Fixed stm32 when receiving data during initialization
Added logs on stm32
Fixed wrong bank erasing on stm32g4
Various fixes in nrf_qspi_nor driver
Added driver for AT456 compatible SPI flash chips
Enabled support for SAMV71
Added mcp23s17 driver
Added STM32L5 support to stm32 driver
Added interrupt support to sx1509b driver
Fixed interrupt handling in sifive, intel_apl, mchp_xec, mcux_igpio driver
Various fixes in intel_apl driver
Added MCP23S17 driver
Fixed port 1 interrupts in mcux lpc driver
Fixed ESP32 implementation
Updated byte order in all drivers
Added support to stm32h7
Added write/read and bus recovery commands to shell
Added bus recovery function to gpio bitbang driver
Fixed fast and fast+ mode bus speeds in several drivers
Added mcux flexcomm driver
Added I2S master DMA support and clock output to stm32 driver
Added Decawave DW1000 driver
Added “no auto start” option and local MAC address support to rf2xx
Added support for Frame Pending Bit (FPB) handling in nrf5
Added CSMA CA transmit capability to nrf5
Added PAN coordinator mode support to nrf5
Added support for promiscuous mode to nrf5
Added support for energy scan function to nrf5
Fixed RX timestamp handling in nrf5
Various fixes to rf2xx
Fixed PLIC register space
Added support for STM32L5 series
Added GIC V3 driver
Fixed ICFGRn access and config in GIC driver
Optimized the arc v2 interrupt unit driver
Added CAVS DSP Intra-DSP Communication (IDC) driver
Added interrupt support to the ft5336 touch controller driver
Added SDL mouse driver
Added a LoRa shell
Replaced counter driver usage with k_timer calls
Various fixes in sx1276 driver
Added support for GSM 07.10 muxing protocol to generic GSM modem
Added support for modem commands that do not have a line ending
Added automatic detection of ublox-sara-r4 modem type
Added automatic setting of APN for ublox-sara-r4
Added sendmsg() support to ublox-sara-r4
Fixed UDP socket closing in ublox-sara-r4
Fixed RSSI calculation for Sara U201
Fixed TCP context release and RX socket src/dst port assignment in wncm14a2a
Changed PPP driver connection to generic GSM modem
Added Microchip XEC driver
Fixed compilation errors in rv32m1_vega pinmux
Tuned PS2 driver to support several mice brands
Added support to stm32h7
Enhanced mcux ftm driver to configure pwm in ticks and allow configuring the clock prescaler
Added mcux tpm driver
Fixed nrfx driver to wait until PWM is stopped before restarting it
Added support for Analog Devices ADXL345 3-axis I2C accelerometer
Added Infineon DPS310 driver
Fixed temperature conversion in SI7006 driver
Added Honeywell MPR driver
Added BQ27421 driver
Added weighted average filter to NXP Kinetis temperature driver
Enabled single shot mode in ENS210 driver
Added forced sampling mode to BME280 driver
Added IIS2MDC magnetometer driver
Added IIS2DLPC accelerometer driver
Added ISM330DHCX IMU driver
Added MEC tachometer driver
Fixed I2C and SPI bus communication in LIS2DH driver
Added uart_mux driver that is used in GSM 07.10 muxing protocol
Added support for parity setting from dts on stm32
Added support for stm32l5
Various fixes in ns16550 driver
Added XMC driver
Added interrupt and runtime configuration support to Xilinx driver
Fixed interrupt support in sifive driver
Enhanced nrfx driver TX only mode support
Added SAMV71 support to sam driver
Added support for DMA client on stm32
Increased clock frequency in mcux flexcomm driver
Added power management support to cc13xx_cc26xx driver
Various fixes in stm32_lptim driver
Removed RTC1 dependency from nrf driver
Various fixes in arcv2_timer0 driver
Fixed TICKLESS=n processing in nrf_rtc and stm32_lptim drivers
Added CAVS DSP wall clock timer driver
Implemented tickless support in xlnx_psttc_timer driver
Added experimental USB Audio implementation.
Added support to stm32wb
Fixed PMA leak at reset on stm32
Various fixes in usb_dc_nrfx driver
Refactored usb_dc_mcux_ehci driver
Added dedicated video init priority
Various fixes in sw_generator and mcux_csi
Fixed video buffer alignment
Added support on stm32g0
Disabled iwdg at boot on stm32
Added scan completion indication to eswifi
Added support to ESP8266 and ESP32
Converted networking to use new k_timeout_t infrastructure
Enhanced new TCP stack support
Added minimal support for TFTP client (RFC 1350)
Added support for network device driver power management
Added support for socketpair() BSD socket API
Added support for QEMU user networking (SLIRP)
Added support to disable automatic network attachment in OpenThread
Added support for Frame Pending Bit handling in OpenThread
Added support for RX frame handling in OpenThread
Added support for TX started notification in OpenThread
Added support for HW CSMA CA in OpenThread
Added support for promiscuous mode in OpenThread
Added support for reading OPAQUE resources with OMA TLV in LWM2M
Added config to enable PAN coordinator mode in IEEE 802.15.4
Added config to enable promiscuous mode in IEEE 802.15.4
Added support for subscribe in Azure cloud sample
Added support for queue mode in lwm2m_client sample
Added support to allow change of the QEMU Ethernet interface name
Added support for PPP IPCP to negotiate used DNS servers
Added support for setting hostname in DHCPv4 request
Fixed binding AF_PACKET socket type multiple times
Fixed LLDPDU data in sent LLDP packets
Fixed and enhance Google IoT sample application documentation
Fixed MQTT cloud sample when polling incoming messages
Fixed LWM2M socket error handling, and pending and reply handling during start
Fixed LWM2M retransmission logic
Fixed LWM2M Cell ID resource initialization
Fixed COAP pending and reply handling
Fixed wpan_serial sample application and enable USB during initialization
Fixed HTTP client payload issue on HTTP upload
Fixed MQTT Websocket incoming data handling and accept packets only in RX
Fixed MQTT Publish message length validation
Fixed IEEE 802.15.4 received frame length validation
IEEE 802.15.4: avoided ACK processing when not needed
IEEE 802.15.4: Now allows energy detection scan unconditionally
Support for LE Advertising Extensions has been added.
The Host is now 5.2 compliant, with support for EATT, L2CAP ECRED mode and all new GATT PDUs.
New application-controlled data length and PHY update APIs.
Legacy OOB pairing support has been added.
Multiple improvements to OOB data access and pairing.
The Host now uses the new thread analyzer functionality.
Multiple bug fixes and improvements
BLE split software Controller:
The Controller is now 5.2 compliant.
A new HCI USB H4 driver has been added, which can interact with BlueZ’s counterpart Host driver.
PHY support is now configurable.
Only control procedures supported by the peer are now used.
The Nordic nRF52820 IC is now supported
2 Mbps PHY support.
Radio deep sleep mode support.
Controller-based privacy support.
BLE legacy software Controller:
The legacy Controller has been removed from the tree.
Build and Infrastructure¶
Zephyr CMake package
The Zephyr main repository now includes a Zephyr CMake package. This allows for registering Zephyr in the CMake user package registry and allows for easier integration into Zephyr applications, by using the CMake function,
find_package(Zephyr ...). Registering the Zephyr CMake package in the CMake user package registry removes the need for setting of
zephyr-env.sh, or running
west zephyr-exportis introduced for easy registration of Zephyr CMake package in the CMake user package registry.
Zephyr Build Configuration CMake package hook. Zephyr offers the possibility of configuring the Zephyr build system through a Zephyr Build Configuration package. A single Zephyr workspace
ZephyrBuildConfig.cmakewill be loaded if present in the Zephyr workspace. This allows users to configure the Zephyr build system on a per workspace setup, as an alternative to using a
.zephyrrcsystem wide file.
A new Devicetree was added. This API is not generated, but is still included via
See the Zephyr v2.3 legacy devicetree macro page for more information, including a link to a migration guide to the new API.
Libraries / Subsystems¶
Add stm32 sdmmc disk access driver, supports stm32f7 and stm32l4
socketpair() function implemented.
eventfd() function (Linux-like extension) implemented.
Add system and device power management support on TI CC13x2/CC26x2.
HALs are now moved out of the main tree as external modules and reside in their own standalone repositories.
New API overview page added.
Reference pages have been cleaned up and organized.
The Devicetree documentation has been expanded significally.
The project roles have been overhauled in the Contribution Guidelines pages.
The documentation on driver-specific APIs has been simplified.
Documentation for new APIs, boards and samples.
Tests and Samples¶
Added samples for USB Audio Class.
Added sample for using POSIX read()/write() with network sockets.