Grant Grundler wrote: > On Sat, Dec 13, 2008 at 01:38:24PM +0400, Manu Abraham wrote: >> Hi, >> >> I am wondering how to handle this: >> >> Does the kernel somehow handle MSI message readback from the PCI config space >> for the MSI message as described in 6.8.1 of the PCI Bus specification 2.3 or >> does a device specific driver have to read the Message Address and Data ? >> >> To put it short: i am wondering how i should read the MSI messages. > > The "message" is actually mapped to an the interrupt vector by the core > generic interrupt handling code in the kernel. > > A "GSI" (Generic Sys Interrupt?) is associated with each entry in > the MSI-X table. Driver then calls request_irq() to bind an interrupt > handler to each GSI. So the driver never directly sees the "message". Oh, you mean the array of irq_handlers in the MSI-X table should correspond to a particular message ? I remember sometime back somebody stated that one might not get the requested number of handlers what you requested. In such a case, if the irq_handlers are mapped in a static fashion, one might not get any interrupt callbacks for a specific functionality of the hardware. Or is there something missing in what i understood ? Regards, Manu -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
