wch_cmake

CMake support for WCH RISC-V microcontrollers (CH32 families), modelled on stm32-cmake. It provides a toolchain file, find_package modules for the CMSIS device headers and the StdPeriph (SPL) drivers, and per-device linker-script generation. Device sources are pulled from wch_libs.

Supported families

Family (long / short)	Devices	Core	ISA / ABI	wch_libs dir(s)
CH32V0 / V0	CH32V002–V007, V003	QingKe V2	rv32ec / ilp32e	CH32V003, CH32V00x
CH32V1 / V1	CH32V103	QingKe V3	rv32imac / ilp32	CH32V10x
CH32V2 / V2	CH32V203, CH32V208	QingKe V4B/C	rv32imac / ilp32	CH32V20x
CH32V3 / V3	CH32V303/305/307	QingKe V4F	rv32imafc / ilp32f (hard float)	CH32V30x
CH32L1 / L1	CH32L103	QingKe V4C	rv32imac / ilp32	CH32L103
CH32X0 / X0	CH32X035	QingKe V4C	rv32imac / ilp32	CH32X035

CH641 / CH643 are present in wch_libs but not yet wired up here (their names don't fit the CH32<letter><digit> scheme the parser assumes).

Toolchains

Two RISC-V toolchains are supported; select with CH32_TARGET_TRIPLET:

• riscv32-wch-elf (default) — WCH's own GCC. Understands the vendor xw ISA extension, which is appended automatically (e.g. rv32imacxw_zicsr).
• riscv-none-elf — the generic xPack toolchain. xw is omitted (e.g. rv32imac_zicsr).

cmake -S . -B build -G Ninja                          # WCH GCC
cmake -S . -B build -G Ninja -DCH32_TARGET_TRIPLET=riscv-none-elf   # xPack GCC

Usage

cmake_minimum_required(VERSION 3.16)
set(CMAKE_TOOLCHAIN_FILE ${CMAKE_CURRENT_SOURCE_DIR}/path/to/wch_cmake/cmake/wch_gcc.cmake)

project(my_firmware C ASM)

# Fetch device sources (from GitHub, or point CH32_LIBS_PATH at a local checkout)
ch32_fetch_cmsis(V2)
ch32_fetch_spl(V2)          # only if you use the SPL drivers

find_package(CMSIS COMPONENTS CH32V2 REQUIRED)
find_package(SPL   COMPONENTS CH32V2 RCC GPIO REQUIRED)

add_executable(my_firmware src/main.c)
target_link_libraries(my_firmware
    SPL::CH32::V2::GPIO
    SPL::CH32::V2::RCC
    CMSIS::CH32::V203C8     # picks device, generates the linker script
    CH32::Nano              # newlib-nano
    CH32::NoSys)            # nosys syscalls stubs

ch32_print_size_of_target(my_firmware)
ch32_generate_hex_file(my_firmware)

Use a local wch_libs checkout instead of fetching:

cmake -S . -B build -DCH32_LIBS_PATH=/path/to/wch_libs

Targets

• CMSIS::CH32::<DEVICE> — device headers, system + startup, and a generated linker script (e.g. CMSIS::CH32::V203C8, CMSIS::CH32::L103C8).
• CMSIS::CH32::<FAMILY|TYPE> — the underlying family/type interface libs.
• SPL::CH32::<NS> and SPL::CH32::<NS>::<DRIVER> — StdPeriph base + per-driver libs, where <NS> is the family (V2) or, for V0, the SDK type (V003 / V00X). Drivers are the uppercased peripheral name (GPIO, RCC, SPI, …).
• CH32::Nano, CH32::NoSys, CH32::Nano::FloatPrint, CH32::Nano::FloatScan — spec/linker helpers.

Helpers

ch32_print_size_of_target, ch32_generate_hex_file, ch32_generate_binary_file, ch32_generate_srec_file, ch32_get_chip_info, ch32_get_memory_info, ch32_print_devices_by_family.

Examples

See examples/cmsis_blink (register-level) and examples/spl_blink (StdPeriph), both of which build one target per supported family.

Layout

cmake/
  wch_gcc.cmake        toolchain entry point
  FindCMSIS.cmake      device headers + startup + linker script
  FindSPL.cmake        StdPeriph drivers
  ch32/
    common.cmake       families, arch flags, memory info, helpers
    devices.cmake      device list + memory sizes
    utilities.cmake    family targets, fetch functions
    linker_ld.cmake    linker-script template
    v0.cmake v1.cmake v2.cmake v3.cmake l1.cmake x0.cmake   per-family config

Each ch32/<family>.cmake declares the family's device types, the ISA base (ec / imac / imafc), ABI, RAM sizes, and device header stem — adding a new family is mostly a matter of adding one such file plus a devices entry.