CONFIG_ATMEL_CLOCKSOURCE_PIT is not available for the default architecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_ATMEL_CLOCKSOURCE_PIT.
Result is shown for kernelversion 5.9.9

Periodic Interval Timer (PIT) support


Linux Kernel Configuration
└─> AT91/Microchip SoCs
└─> Periodic Interval Timer (PIT) support

Select this to get a clocksource based on the Atmel Periodic Interval
Timer. It has a relatively low resolution and the TC Block clocksource
should be preferred.