Nested interrupts again

<div class='quotetop'>QUOTE (jan @ Sep 8 2009, 02:03 PM) <{post_snapback}> (index.php?act=findpost&pid=23780)</div>

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I need to make a small patch inside uClinux kernel for NIOS2. I need to enable one specific IRQ to have absolute priority over all atomic processes running in Linux - over threads, over other ISRs, over instruction traps and so on - simply said - over any atomic section in uClinux means.[/b]

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You don&#39;t.

I suppose you don&#39;t want to hear this, but it&#39;s not a good idea to do such high priority stuff with the CPU that runs Linux.

You should either do this in FPGA hardware, or implement a second processor in the FPGA that independently handles the high-priority stuff.

When using a not modifiable hardware things like you describe are unavoidable, but with an FPGA processor, IMHO, this is not appropriate.

-Michael