The CONFIG_CLOCK_CONTROL_NRF_K32SRC_EXT_FULL_SWING=y Kconfig option causes kernel booting to hang at line 505 of clock_control_nrf.c.
This is on the v1.7-branch of NCS (v2.6.99-ncs1-1 tag of NCS zephyr). I'm running a custom board using an nrf52840.
To test, create boards/nrf52840dk_nrf52840.conf in the blinky sample and enable the flag. Building & flashing the example to the nrf52840DK reproduces the issue.
