aarch64-xilinx-linux-g++ missing, using aarch64-linux-gnu-g++ instead

[vmayoral]

Connected to #69.

The instructions at https://github.com/Xilinx/Vitis-Tutorials/blob/master/Getting_Started/Vitis/Part4.md read as:

...
$(CXX) -Wall -g -std=c++11 ../../src/host.cpp -o app.exe -I/usr/include/xrt -lOpenCL -lpthread -lrt -lstdc++
...

cross-compilation wont' work this way since CXX contains the following in my environment with Vitis 2020.2:

echo $CCX
aarch64-xilinx-linux-g++ -march=armv8-a+crc -mtune=cortex-a72.cortex-a53 --sysroot=/tools/Xilinx/Vitis/2020.2/data/emulation/qemu/unified_qemu_v5_0/sysroots/aarch64-xilinx-linux

aarch64-xilinx-linux-g++ is nowhere to be found in my file system. Instead, I used aarch64-linux-gnu-g++ to successfully cross-compile things.

Edit: I was wrong, I did find aarch64-xilinx-linux-g++ after doing a better search.

[randyh62]

I am not sure where this instruction or the $(CXX) variable came from. It seems to be a Makefile variable, but I could not find the environment-setup-aarch64-xilinx-linux script described in the line "source /environment-setup-aarch64-xilinx-linux" in the tutorial. The command, which you found, should be located as follows:

$XILINX_VITIS/gnu/aarch64/lin/aarch64-linux/bin/aarch64-linux-gnu-g++

[rwarmstr]

${CXX} is an environment variable that's set when you source the cross-compilation environment set up script. That's a necessary step when building on the command line.

It looks like you may not have done this before building and it's picking up the QEMU toolchain instead, which might accidentally work in some circumstances but can cause issues generally.

[vmayoral]

With the right changes indicated at #70 (comment) then we're set and the following flow works (I just confirmed it):

setup XRT

cd /home/erle/Desktop/Xilinx; git clone https://github.com/Xilinx/XRT
cd XRT; sudo src/runtime_src/tools/scripts/xrtdeps.sh  # install dependencies
source /tools/Xilinx/Vitis/2020.2/settings64.sh  # necessary for ERT
export PATH="/usr/bin":$PATH  # FIXME: adjust path for CMake 3.5+
cd build; ./build.sh
cd Release; sudo apt-get install ./xrt_*-amd64-xrt.deb

Fetch Vitis-Tutorials

cd ~; git clone https://github.com/Xilinx/Vitis-Tutorials

set environment

Requires to first fetch rootfs and sysroots from here, while putting it into a coherent folder-structure. Then:

cd ~/Vitis-Tutorials/Getting_Started/Vitis/example/zcu102/hw/
source /tools/Xilinx/Vitis/2020.2/settings64.sh
source /opt/xilinx/xrt/setup.sh
unset LD_LIBRARY_PATH
export PLATFORM_REPO_PATHS="/home/erle/Desktop/Xilinx/xilinx_zcu102_base_202020_1"
export ROOTFS=/home/erle/Desktop/Xilinx/rootfs 
source /home/erle/Desktop/Xilinx/rootfs/ir/environment-setup-aarch64-xilinx-linux

build the example

${CXX} -Wall -g -std=c++11 ../../src/host.cpp -o app.exe -I/usr/include/xrt -lOpenCL -lpthread -lrt -lstdc++
v++ -c -t hw --config ../../src/zcu102.cfg -k vadd -I../../src ../../src/vadd.cpp -o vadd.xo 
v++ -l -t hw --config ../../src/zcu102.cfg ./vadd.xo -o vadd.xclbin
v++ -p -t hw --config ../../src/zcu102.cfg ./vadd.xclbin --package.out_dir package --package.rootfs ${ROOTFS}/rootfs.ext4 --package.sd_file ${ROOTFS}/Image --package.sd_file xrt.ini --package.sd_file app.exe --package.sd_file vadd.xclbin --package.sd_file run_app.sh

I'm having issues getting the kernels "to work" but I'll debug that a bit more and open another ticket if necessary.

I believe we can close this ticket @rwarmstr and @randyh62 once we address the tiny bit of #69 (comment).

[dj-park]

For those of you still having similar issues... in my experience, when installing zynqmp command image,
if I install it with
./sdk.sh -y -d . -p
and then cp it to /opt/platforms (for example), I had this issue.

I had to cp the directory to /opt/platforms/ first and then run ./sdk.sh -y -d . -p.
I don't think setting XRT is necessary for embedded platform.