I am reposting here an issue previously published on the Xilinx forum https://forums.xilinx.com/t5/OpenAMP/Zynq-AMP-CPU1-baremetal-access-to-gem0/m-p/827569#M418
still without a solution. I repeated the test on PicoZed 7015 board and on the Zybo as well.
My system configuration is as follows:
Vivado 2016.3 on a Linux Debian host
Standard Zynq design over Zybo (just use ethernet and the ps7_uart)
CPU0 -> baremetal "Hello World" application
CPU1 -> baremetal "lwIP echo server" with lwIP library to use gem0
CPU0 is run as master CPU (and launching the ps7_init methods), while CPU1 is started later with USE_AMP flag activated.
Goal: To have the CPU1 accessing the Ethernet with LwIP and keeping the CPU0 available for other tasks (most probable, it will run Linux later on).
Issue: Whenever the USE_AMP flag is turned on on CPU1, the "LwIP echo server" did not send packages over Ethernet (verified with Wireshark) neither answer back to ping. In the other case, when USE_AMP is deactivated, the Ethernet works as expected yet CPU0 stops working (due to the SCU contention)...
Have somebody face the same issue?
In the attachment, you might find the reference project, with CPU0/CPU1 example application (from the XSDK template).