Re: MSI to memory?

[Helge Hafting]

Davide Rossetti wrote:

> Rajesh Shah wrote:
>
> > What type of usage model did you have in mind to have the
> >
> > device write to memory instead of using MSI for interrupts?
> >  
> for instance for a fast wake-up trick. the driver loops on a memory 
> location until the MSI write access changes the memory content...

Won't that put a bad load on the bus?  Someone else might need it:
* Another cpu in a smp system
* Any device doing bus-master transfers, even in a UP system

That polling loop had better be guaranteed to be _very_ short.

Helge Hafting
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