[lkml]   [2007]   [May]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 1/2] msi: Invert the sense of the MSI enables.
 > > In addition to PCI INTx compatible interrupt emulation, PCI Express
> > requires support of MSI or MSI-X or both.
> Which suggests that INTx support is required.
> I do not find any wording that suggest the opposite.
> I do see it stated that it is intended to EOL support for INTx at
> some point.
> Where did you see it mentioned that INTx was optional?

I don't see any requirement that a device that generates MSI
interrupts must also be able to signal the same interrupts via INTx.
The spec explicitly says:

"All PCI Express device Functions that are capable of generating
interrupts must support MSI or MSI-X or both."

but there is no corresponding explicit requirement that legacy INTx
mode be supported, so it certainly seems permitted for a device not to
generate INTx interrupts. In fact as you alluded to, the spec says,

"The legacy INTx emulation mechanism may be deprecated in a future
version of this specification."

and I wouldn't think the intention would be for one version of the
spec to *require* something that is planned on being deprecated later.

And the Pathscale guys were pretty confident that their device was
compliant with the PCIe spec.

- R.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2007-05-25 23:11    [W:0.068 / U:13.552 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site