--- zzzz-none-000/linux-3.10.107/arch/arm/configs/iop32x_defconfig	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/arm/configs/iop32x_defconfig	2021-02-04 17:41:59.000000000 +0000
@@ -106,6 +106,7 @@
 CONFIG_DEBUG_KERNEL=y
 CONFIG_DEBUG_USER=y
 CONFIG_DEBUG_LL=y
+CONFIG_DEBUG_LL_UART_8250=y
 CONFIG_KEYS=y
 CONFIG_KEYS_DEBUG_PROC_KEYS=y
 CONFIG_CRYPTO_NULL=y