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Diffstat (limited to 'Documentation/IRQ.txt')
| -rw-r--r-- | Documentation/IRQ.txt | 24 |
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diff --git a/Documentation/IRQ.txt b/Documentation/IRQ.txt deleted file mode 100644 index 4273806a606b..000000000000 --- a/Documentation/IRQ.txt +++ /dev/null @@ -1,24 +0,0 @@ -=============== -What is an IRQ? -=============== - -An IRQ is an interrupt request from a device. -Currently they can come in over a pin, or over a packet. -Several devices may be connected to the same pin thus -sharing an IRQ. - -An IRQ number is a kernel identifier used to talk about a hardware -interrupt source. Typically this is an index into the global irq_desc -array, but except for what linux/interrupt.h implements the details -are architecture specific. - -An IRQ number is an enumeration of the possible interrupt sources on a -machine. Typically what is enumerated is the number of input pins on -all of the interrupt controller in the system. In the case of ISA -what is enumerated are the 16 input pins on the two i8259 interrupt -controllers. - -Architectures can assign additional meaning to the IRQ numbers, and -are encouraged to in the case where there is any manual configuration -of the hardware involved. The ISA IRQs are a classic example of -assigning this kind of additional meaning. |