APIC trigger mode

Sebastian Sumpf Sebastian.Sumpf at genode-labs.com
Fri Mar 16 16:11:44 CET 2012


On 03/15/2012 10:35 PM, Adam Lackorzynski wrote:
> 
> On Tue Mar 13, 2012 at 13:02:36 +0100, Sebastian Sumpf wrote:
>> I have a question regarding the APIC-interrupt mode settings on x86. I
>> see that one has to set the mode externally in Fiasco.OC using the
>> 'l4_icu_set_mode' call. Also I had a look at Nova which seems to program
>> these modes from within the kernel, using edge/high for IRQ 0-15 and
>> level-low for IRQ 16-23. Would that be a valid assumption to program the
>> modes for Fiasco.OC x86 also, or is there an other way to find out the
>> interrupt-trigger modes of IRQs (other than the ones found in
>> ACPI-MADT)? Why is it necessary to set these modes outside the kernel?
> 
> Generally, this depends on the device and thus it's configurable for a
> driver. If some combination is not possible then it should just be
> ignored/fail. Does this help?
> 

Kind of, thanks.

Sebastian





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