On Mon, 2009-02-23 at 12:28 -0500, Matthew Wilcox wrote:
> From: Matthew Wilcox <[email protected]>
>
> Add the new API pci_enable_msi_block() to allow drivers to
> request multiple MSI and reimplement pci_enable_msi in terms of
> pci_enable_msi_block. Ensure that the architecture back ends don't
> have to know about multiple MSI.
>
> diff --git a/arch/powerpc/kernel/msi.c b/arch/powerpc/kernel/msi.c
> index 3bb7d3d..0c16e2a 100644
> --- a/arch/powerpc/kernel/msi.c
> +++ b/arch/powerpc/kernel/msi.c
> @@ -19,6 +19,10 @@ int arch_msi_check_device(struct pci_dev* dev, int nvec, int type)
> return -ENOSYS;
> }
>
> + /* PowerPC doesn't support multiple MSI yet */
> + if (type == PCI_CAP_ID_MSI && nvec > 1)
> + return 1;
> +
> if (ppc_md.msi_check_device) {
> pr_debug("msi: Using platform check routine.\n");
> return ppc_md.msi_check_device(dev, nvec, type);
That bit:
Acked-by: Michael Ellerman <[email protected]>
I'll tell benh to expect this hunk to show up sometime via Jesse's tree.
Looks good otherwise, not sure if we'll ever implement it, but good to
have. Is AHCI the only driver you're planning on using it for ATM?
cheers
--
Michael Ellerman
OzLabs, IBM Australia Development Lab
wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)
We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person
On Tue, Mar 03, 2009 at 11:16:13AM +1100, Michael Ellerman wrote:
> > diff --git a/arch/powerpc/kernel/msi.c b/arch/powerpc/kernel/msi.c
> > index 3bb7d3d..0c16e2a 100644
> > --- a/arch/powerpc/kernel/msi.c
> > +++ b/arch/powerpc/kernel/msi.c
> > @@ -19,6 +19,10 @@ int arch_msi_check_device(struct pci_dev* dev, int nvec, int type)
> > return -ENOSYS;
> > }
> >
> > + /* PowerPC doesn't support multiple MSI yet */
> > + if (type == PCI_CAP_ID_MSI && nvec > 1)
> > + return 1;
> > +
> > if (ppc_md.msi_check_device) {
> > pr_debug("msi: Using platform check routine.\n");
> > return ppc_md.msi_check_device(dev, nvec, type);
>
> That bit:
>
> Acked-by: Michael Ellerman <[email protected]>
>
> I'll tell benh to expect this hunk to show up sometime via Jesse's tree.
Thanks!
> Looks good otherwise, not sure if we'll ever implement it, but good to
> have. Is AHCI the only driver you're planning on using it for ATM?
That's the only one I know where it's important. I think some PCIe
bridges would like to have multiple MSI. And I think some hardware
designs (not from Intel, from other companies who've talked to me) are
in the pipe to use multiple MSI, because it's cheaper than using MSI-X.
--
Matthew Wilcox Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours. We can't possibly take such
a retrograde step."