I have a PIT running every millisecond on my Cortex-M4. This works fine while a Linux with kernel 3.0 is running on the A5. However, after switching to kernel 3.13 the PIT interrupt on the M4 is not triggered anymore.
When I enable the PIT in Linux(
System Type-> Freescale i.MX family-> Freescale i.MX support->Vybrid Family VF610 support->Clocksource for scheduler clock (Use PIT timer)
) the interrupt is also triggered on the M4, but Linux crashes regularly. The shell simply doesn't react anymore. I guess it doesn't like that the scheduler clock is used by someone else.
How can I prevent Linux from disabling interrupts that it doesn't use? Linux should only touch the registers of the interrupts it uses and leave all other vectors to the M4.