I have got an iMX7s on custom board with 512MB Ram. I successfully run the hello_world example and now I am trying to get the pingpong example to work. On the M4 side there are no problems. I can boot and it shows:
RPMSG PingPong FreeRTOS RTOS API Demo...
RPMSG Init as Remot
But on the Linux side there are a few problems:
If I don't enable rpmsg in the devicetree I can boot and load the pingpong module using modprobe imx_rpmsg_pingpong. Additionaly rpmsg is shown in /sys/bus and /sys/module/ . But nothing else happens.
If I set rpmsg in the devicetree to "okay" I just see this:
Starting kernel ...
Uncompressing Linux... done, booting the kernel.
Things that I've changed so far:
- obviously modifying the DT
- set rpmsg to "ok"
- set usable memory
linux,usable-memory = <0x80000000 0x1ff00000>;
- changing the vring in the Linux kernel in imx_rpmsg.c from BFFF0000 --> 9FFF0000 (and BFFF8000 --> 9FFF8000)
- changing the vring in FreeRTOS in platform_info.c the same way
- RPMsg and Pingpong are enabled in the Kernel