On Thu, Feb 04, 2016 at 04:21:08PM +0000, Zytaruk, Kelly wrote: > > -----Original Message----- > > From: Bjorn Helgaas [mailto:helgaas@xxxxxxxxxx] > > Sent: Thursday, February 04, 2016 10:14 AM > > To: Zytaruk, Kelly > > Cc: bhelgaas@xxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; linux- > > kernel@xxxxxxxxxxxxxxx; Alex Williamson; Yu Zhao > > Subject: Re: [PATCH] PCI: Support SRIOV on Legacy EndPoint device > > > > [+cc Alex, Yu (participants in previous discussion)] > > > > Hi Kelly, > > > > On Thu, Feb 04, 2016 at 09:48:26AM -0500, Kelly Zytaruk wrote: > > > Some AMD GPUs have hardware support for grapics SRIOV. > > > If the GPU has a display output then the GPU needs to support Legacy VGA > > operation. > > > If CLASS_CODE = VGA then the device should have a Port Type = Legacy > > EndPoint. > > > Therefore in order to enable SRIOV on a GPU with a display output > > LEGACY_END_POINT is supported as a valid Port Type. > > > > > > Signed-off-by: Kelly Zytaruk <kelly.zytaruk@xxxxxxx> > > > > We had an interesting discussion about this two years ago: > > http://lkml.kernel.org/r/B756807489D6244883AC0B799A6EEC15EAB2E8@store > > xdag02.amd.com > > Unfortunately 2 years ago I couldn't complete your request as it > would have disclosed Information about an unannounced technology > that we were working on. We have recently made that technology > public and I can now send you the requested information. > > Please include a reference to that discussion in your changelog. In that > > discussion, I also asked for some details (dmesg and lspci info) that motivate the > > change, so please collect and add a reference to them as well. > > The information that you ask for is included below. I have > abbreviated it so that this does not become a huge email. I can > send full logs if you want them. Can you open a bugzilla at http://bugzilla.kernel.org and attach the full logs there? Then we can include the URL in your patch changelog. > > It's not clear to me why we check the device type at all. If > > there's no spec restriction on the types of devices that can have > > an SR-IOV capability, we should consider removing the test > > altogether (Alex mentioned this possiblity in the earlier > > discussion). > > I am as well not clear why the check is in there. I would be just > as happy either adding TYPE_LEG_END or removing the check all > together. I don't know what the side effects of removing the check > would be. I don't have any sriov devices other than a graphics card > to test with so I wouldn't be able to test other scenarios. If we don't have a reason to do the check, I think we should just remove it altogether. Bjorn -- 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
