On Monday 06 June 2011, George Kashperko wrote:

quoted

For an interrupt controller, it should be ok to have it initialized
late, as long as it's only responsible for the devices on the same
bus and not for instance for IPI interrupts. Just make sure that you
do the bus scan and the initialization of the IRQ driver before you
initialize any drivers that rely in on the interrupts to be working.

Without proper timer init (which requires both the chipcommon and mips
cores knowledge) kernel will get hung somewhere inside calibrate_delay.
It could get addressed if get bus scan called in arch_init_irq or
plat_time_init - both are executed before calibrate_delay and with slab
available.

Ok, so you need the interrupt controller to be working for the timer tick,
right? I think another option (if that's not what you mean already) would
be to have a simpler way to find a device on the bus that can be called
before doing a full scan.

Early drivers would then have to know what is there and call a function
like "bcma_find_device(BCMA_DEV_ID_IRQ)", while drivers that are not
required to be up just register a regular device driver with a probe
function that gets called after the bus scan creates device structures.

	Arnd