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@@ -18,7 +18,7 @@
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<h2 class='titleHead'>The Linux Kernel Module Programming Guide</h2>
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<div class='author'><span class='ecrm-1200'>Peter Jay Salzman, Michael Burian, Ori Pomerantz, Bob Mottram, Jim Huang</span></div><br />
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-<div class='date'><span class='ecrm-1200'>December 9, 2022</span></div>
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+<div class='date'><span class='ecrm-1200'>December 11, 2022</span></div>
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@@ -4956,13 +4956,13 @@ naming for <span class='ecti-1000'>Bottom Halves</span>) statistically book-keep
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</p><!-- l. 1844 --><p class='indent'> The way to implement this is to call
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<code> <span class='ectt-1000'>request_irq()</span>
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</code> to get your interrupt handler called when the relevant IRQ is received.
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-</p><!-- l. 1846 --><p class='indent'> In practice IRQ handling can be a bit more complex. Hardware is often
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-designed in a way that chains two interrupt controllers, so that all the IRQs
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-from interrupt controller B are cascaded to a certain IRQ from interrupt
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-controller A. Of course, that requires that the kernel finds out which IRQ it
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-really was afterwards and that adds overhead. Other architectures offer some
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-special, very low overhead, so called "fast IRQ" or FIQs. To take advantage of
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-them requires handlers to be written in assembler, so they do not really
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+</p><!-- l. 1846 --><p class='indent'> In practice IRQ handling can be a bit more complex. Hardware is often designed
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+in a way that chains two interrupt controllers, so that all the IRQs from
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+interrupt controller B are cascaded to a certain IRQ from interrupt controller A.
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+Of course, that requires that the kernel finds out which IRQ it really was
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+afterwards and that adds overhead. Other architectures offer some special,
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+very low overhead, so called "fast IRQ" or FIQs. To take advantage of them
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+requires handlers to be written in assembly language, so they do not really
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fit into the kernel. They can be made to work similar to the others, but
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after that procedure, they are no longer any faster than "common" IRQs.
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SMP enabled kernels running on systems with more than one processor
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jserv