Signed-off-by: Guo Yejun <[email protected]> --- docs/howto/cross-compiler-howto.mdwn | 60 ++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 docs/howto/cross-compiler-howto.mdwn
diff --git a/docs/howto/cross-compiler-howto.mdwn b/docs/howto/cross-compiler-howto.mdwn new file mode 100644 index 0000000..535cd9a --- /dev/null +++ b/docs/howto/cross-compiler-howto.mdwn @@ -0,0 +1,60 @@ +Cross Compiler HowTo +==================== + +Beignet supports both PC devices with full profile and embedded/handheld +devices with embeded profile. This document describes how to build Beignet +and OpenCL kernels for a target machine (embedded/handheld devices) in a +host machine with the help of cross compiler, and also the large-size-reduced +Beignet driver package for the target machine. + +Build Beignet with a cross compiler +----------------------------------- + +Besides the general cross compile methods, reference the following options when +configure Beignet with cmake. + +- LLVM_INSTALL_DIR + Beignet depends on llvm+clang, this option refers to the path of llvm-config, + llvm-as, llvm-link and clang in the cross compiler environment. + +- CMAKE_SKIP_RPATH + Some cross compiler systems forbid the usage of rpath in binaries/libraries, + set this option to be TRUE. + +- GEN_PCI_ID + It is the GPU pci_id of the target machine, for example, 0x0162 is the pciid + of Intel Ivybridge GPU, and 0x0f31 is Intel Baytrail GPU. The information can + be queried with command 'lspci -n'. + +- CMAKE_INSTALL_PREFIX + This option controls the prefix of installation path. + +Distribution of large-size-reduced Beignet driver package +--------------------------------------------------------- + +On embedded/handheld devices, storage and memory are scarce, it is necessary to +provide only the OpenCL runtime library without OpenCL compiler, and only the +executable binary kernel is supported on such devices. + +It means that just distribute libcl.so and libgbeinterp.so (~320k in total after strip) +are enough for OpenCL embeded profile in the target machine. + +Build OpenCL kernels with OpenCL offline compiler +------------------------------------------------- + +Since the target machine does not contain the OpenCL compiler, the OpenCL source +kernel need to be compiled with an OpenCL offline compiler (gbe_bin_generater) +into binary kernel in the host machine, and the OpenCL application can load the +binary kernel with function clCreateProgramWithBinary. + +The OpenCL offline compiler gbe_bin_generater is the result of Beignet build and +locates at .../your_path_to_build/backend/src/gbe_bin_generater, see below for the +command options. + +gbe_bin_generater INFILE [-pbuild_parameter] -oOUTFILE -tGEN_PCI_ID + +For example, the following command builds OpenCL source kernel from file 'mykernel.cl' +for Ivybridge with pci_id 0x0162, and write the result (executable binary kernel) +into file 'mykernel.bin'. + +gbe_bin_generater mykernel.cl -omykernel.bin -t0x0162 -- 1.8.3.2 _______________________________________________ Beignet mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/beignet
