Re: pci_enable_msi() for everyone?

From: Grant Grundler
Date: Mon Jun 06 2005 - 23:23:04 EST


On Mon, Jun 06, 2005 at 07:08:33PM -0400, Jeff Garzik wrote:
> Not only the differences DaveM mentioned, but also simply that you may
> assume your interrupt is not shared with anyone else.

I had the impression the CPU vector could be shared.
But PCI 2.3 spec says:
| An MSI is by definition a non-shared interrupt that enforces data
| consistency (ensures the iterrupt service routine accesses the most
| recent data). The system guarantees that any data written by the
| device prior to sending the MSI has reached its final destination
| before the interrupt service routine accesses that data. Therefore,
| a device driver is not required to read its device before servicing
| its MSI.


I guess that's pretty clear....

grant
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