How to mask IRQ

[Thomas Doerfler]

Hello Sergei,

I have read the current discussion and what I do not yet understand in
your approach is how you manage interrupts between the "off the shelf"
BSP drivers and the application specific interrupts. When you "manually
manage" IRQ masks in the interrupt handlers, they get more and more
board specific and writing portable drivers might get more difficult.

All in all I think that, although your approach looks promising, it
would require (another) major rework of the RTEMS interrupt API. We
already have two APIs now and I think for RTEMS it is a bad idea to get
a third one.

I think the initial request from Leon should be considered, to extend
the "new exception processing" API with some means to disable/enable
certain interrupt controller inputs either from application level (well,
we already have that, I think) or from within an interrupt handler. IMHO
 it would be nice if any interrupt handler can enable/disable the
request input of any other interrupt source, therefore I would recommend
not to use a special return value to manage this, but function calls to
manage this.

Any comments?

wkr,
Thomas.




Sergei Organov schrieb:
> 
> 
>>As an example, our data recording system needs to acquire upto 12 fast
>>input channels, while acquired messages must be time stamped with high
>>accuracy. Obviously, the faster the channel the more time stamp error
>>is significant...:-))
>>
>>Summarizing my opinion, I think this will be great to have two (enough?) 
>>interrupts processing models - one existing (Eric - thanks!) and one Sergei 
>>talks about, but how to implement this?
> 
> 
> Those one I talk about was there before Eric's work, and still is, so we
> already have two of them. However, having two interrupt processing
> models is not a good solution, IMHO. Though I don't believe automatic
> interrupts prioritization worth the trouble especially when no PIC is
> available, it could be done using the model I advocate by means of
> manually managing the IRQ masks in the ISR handlers. Besides, that's
> what the original post was all about, -- inability to manage IRQ masks
> from interrupt handler.
> 


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