22 Jul
2011
22 Jul
'11
4:56 a.m.
On 7/21/2011 7:00 PM, Russell King - ARM Linux wrote:
On Thu, Jul 21, 2011 at 11:03:04AM +0530, Santosh Shilimkar wrote:
Just talking on behalf of OMAP, we can't offline CPU0 and limitation would remain in future OMAPs too.
Apart from the broken IRQ migration, and the way CPU0 immediately reawakes if it is offlined on OMAP4 (even when IRQs are migrated off CPU0) because omap_read_auxcoreboot0() returns 0, is there any other reason?
With fixed IRQ migration and forcing CPU0 into an infinite WFI loop, I can offline CPU0 and still have a running system.
The secure software runs only on CPU0 and that's the biggest limitation. Other issues like hand-shake as you pointed out, power sequencing etc can be worked around.
Regards Santosh