diff --git a/toolchains/c906-v261.toolchain.cmake b/toolchains/c906-v261.toolchain.cmake
new file mode 100644
index 0000000..b8a2567
--- /dev/null
+++ b/toolchains/c906-v261.toolchain.cmake
@@ -0,0 +1,36 @@
+set(CMAKE_SYSTEM_NAME Linux)
+set(CMAKE_SYSTEM_PROCESSOR riscv64)
+set(C906 True)
+
+if(DEFINED ENV{RISCV_ROOT_PATH})
+    file(TO_CMAKE_PATH $ENV{RISCV_ROOT_PATH} RISCV_ROOT_PATH)
+else()
+    message(FATAL_ERROR "RISCV_ROOT_PATH env must be defined")
+endif()
+
+set(RISCV_ROOT_PATH ${RISCV_ROOT_PATH} CACHE STRING "root path to riscv toolchain")
+
+set(CMAKE_C_COMPILER "${RISCV_ROOT_PATH}/bin/riscv64-unknown-linux-gnu-gcc")
+set(CMAKE_CXX_COMPILER "${RISCV_ROOT_PATH}/bin/riscv64-unknown-linux-gnu-g++")
+
+set(CMAKE_FIND_ROOT_PATH "${RISCV_ROOT_PATH}/riscv64-unknown-linux-gnu")
+
+set(CMAKE_SYSROOT "${RISCV_ROOT_PATH}/sysroot")
+
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)
+
+set(CMAKE_C_FLAGS "-march=rv64gcv0p7_zfh_xtheadc -mabi=lp64d -mtune=c906")
+set(CMAKE_CXX_FLAGS "-march=rv64gcv0p7_zfh_xtheadc -mabi=lp64d -mtune=c906")
+
+# cache flags
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS}" CACHE STRING "c flags")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}" CACHE STRING "c++ flags")
+
+# export RISCV_ROOT_PATH=/home/nihui/osd/Xuantie-900-gcc-linux-5.10.4-glibc-x86_64-V2.6.1
+
+# cmake -DCMAKE_TOOLCHAIN_FILE=../../toolchains/c906-v261.toolchain.cmake -DCMAKE_C_FLAGS="-fno-rtti -fno-exceptions" -DCMAKE_CXX_FLAGS="-fno-rtti -fno-exceptions" -DCMAKE_INSTALL_PREFIX=install -DCMAKE_BUILD_TYPE=Release `cat ../../opencv4_cmake_options.txt` -DBUILD_opencv_world=OFF -DOPENCV_DISABLE_FILESYSTEM_SUPPORT=ON ..
+
+# /home/nihui/osd/xuantie-qemu-x86_64-Ubuntu-18.04-20230825-0120/bin/qemu-riscv64 -cpu c906fdv -L /home/nihui/osd/Xuantie-900-gcc-linux-5.10.4-glibc-x86_64-V2.6.1/sysroot ./opencv-mobile-test
diff --git a/toolchains/riscv64-unknown-linux-musl.toolchain.cmake b/toolchains/riscv64-unknown-linux-musl.toolchain.cmake
new file mode 100644
index 0000000..27ab640
--- /dev/null
+++ b/toolchains/riscv64-unknown-linux-musl.toolchain.cmake
@@ -0,0 +1,34 @@
+set(CMAKE_SYSTEM_NAME Linux)
+set(CMAKE_SYSTEM_PROCESSOR riscv64)
+set(C906 True)
+
+if(DEFINED ENV{RISCV_ROOT_PATH})
+    file(TO_CMAKE_PATH $ENV{RISCV_ROOT_PATH} RISCV_ROOT_PATH)
+else()
+    message(FATAL_ERROR "RISCV_ROOT_PATH env must be defined")
+endif()
+
+set(RISCV_ROOT_PATH ${RISCV_ROOT_PATH} CACHE STRING "root path to riscv toolchain")
+
+set(CMAKE_C_COMPILER "${RISCV_ROOT_PATH}/bin/riscv64-unknown-linux-musl-gcc")
+set(CMAKE_CXX_COMPILER "${RISCV_ROOT_PATH}/bin/riscv64-unknown-linux-musl-g++")
+
+set(CMAKE_FIND_ROOT_PATH "${RISCV_ROOT_PATH}/riscv64-unknown-linux-musl")
+
+set(CMAKE_SYSROOT "${RISCV_ROOT_PATH}/sysroot")
+
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)
+
+set(CMAKE_C_FLAGS "-march=rv64gcv0p7_zfh_xtheadc -mabi=lp64d -mtune=c906")
+set(CMAKE_CXX_FLAGS "-march=rv64gcv0p7_zfh_xtheadc -mabi=lp64d -mtune=c906")
+
+# cache flags
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS}" CACHE STRING "c flags")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}" CACHE STRING "c++ flags")
+
+# export RISCV_ROOT_PATH=/home/nihui/osd/host-tools/gcc/riscv64-linux-musl-x86_64
+
+# cmake -DCMAKE_TOOLCHAIN_FILE=../../toolchains/riscv64-unknown-linux-musl.toolchain.cmake -DCMAKE_C_FLAGS="-fno-rtti -fno-exceptions" -DCMAKE_CXX_FLAGS="-fno-rtti -fno-exceptions" -DCMAKE_INSTALL_PREFIX=install -DCMAKE_BUILD_TYPE=Release `cat ../../opencv4_cmake_options.txt` -DBUILD_opencv_world=OFF -DOPENCV_DISABLE_FILESYSTEM_SUPPORT=ON ..