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Re: what is MSI ? (apparently related to SMP and interrupts)

On 6/27/06, Arjan van de Ven <arjan@xxxxxxxxxxxxx> wrote: 
On Tue, 2006-06-27 at 12:52 -0600, Jim Cromie wrote:
> its been mentioned repeatedly on LKML,
> where they all know, and dont need it spelled out.
>
> Assuming I understand the answer, Ill add it to glossary.
>
> --

message signaled interrupts

think of it like PCI interrupts but then using a special 32 bit number
and not a number between 0 and 255.
These also use the normal pci data lanes not some magic all over the
chipset; which means that a device can basically have as many interrupts
as it wants rather than 4 (1 in practice) for legacy PCI interrupts, and
there are also no interrupt sharing issues, since there are just so many
numbers for interrupts...

There are a few chipsets that support MSI, even though more and more
are supporting it.
Om.

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