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")

if(NOT CMAKE_FIND_ROOT_PATH_MODE_PROGRAM)
    set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
endif()
if(NOT CMAKE_FIND_ROOT_PATH_MODE_LIBRARY)
    set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
endif()
if(NOT CMAKE_FIND_ROOT_PATH_MODE_INCLUDE)
    set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
endif()
if(NOT CMAKE_FIND_ROOT_PATH_MODE_PACKAGE)
    set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)
endif()

set(CMAKE_C_FLAGS "-march=rv64gcv0p7_zfh_xtheadc -mabi=lp64d -mtune=c906 -DC906=1 -static")
set(CMAKE_CXX_FLAGS "-march=rv64gcv0p7_zfh_xtheadc -mabi=lp64d -mtune=c906 -DC906=1 -static")

# 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-V2.2.2
# cmake -DCMAKE_TOOLCHAIN_FILE=../toolchains/c906-v222.toolchain.cmake -DCMAKE_BUILD_TYPE=release -DNCNN_BUILD_TESTS=ON -DNCNN_OPENMP=OFF -DNCNN_THREADS=OFF -DNCNN_RUNTIME_CPU=OFF -DNCNN_RVV=ON -DNCNN_SIMPLEOCV=ON -DNCNN_BUILD_EXAMPLES=ON ..