minimal working example, still fails shutdown

prj.conf

@@ -0,0 +1,37 @@
+# c version
+CONFIG_MAIN_STACK_SIZE=8192
+
+# logging
+CONFIG_LOG=n
+CONFIG_CONSOLE=n
+CONFIG_EARLY_CONSOLE=n
+CONFIG_PRINTK=n
+
+# gpio support
+CONFIG_GPIO=y
+
+# uart
+CONFIG_SERIAL=y
+CONFIG_UART_INTERRUPT_DRIVEN=n
+CONFIG_UART_NS16550=y
+
+# i2c
+CONFIG_I2C=y
+
+# OpenAMP support
+CONFIG_OPENAMP=y
+CONFIG_OPENAMP_RSC_TABLE=y
+
+# IPC/Mailbox
+CONFIG_IPM=y
+CONFIG_MBOX=y
+
+# Optional: RPMsg for communication
+CONFIG_RPMSG_SERVICE=y
+
+# build
+CONFIG_NO_OPTIMIZATIONS=n
+CONFIG_SIZE_OPTIMIZATIONS=n
+CONFIG_SPEED_OPTIMIZATIONS=n
+CONFIG_DEBUG_OPTIMIZATIONS=y
+CONFIG_DEBUG_THREAD_INFO=y