On Thu, Jul 27, 2023 at 11:45:22AM +0800, Shuai Xue wrote: > > > On 2023/7/26 04:59, Bjorn Helgaas wrote: > > On Mon, Jul 24, 2023 at 10:18:07AM +0100, Jonathan Cameron wrote: > >> On Mon, 24 Jul 2023 10:34:08 +0800 > >> Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx> wrote: > >>> On 2023/7/10 20:04, Shuai Xue wrote: > >>>> On 2023/6/16 16:39, Shuai Xue wrote: > >>>>> On 2023/6/6 15:49, Shuai Xue wrote: > > > >>>>>> This patchset adds the PCIe Performance Monitoring Unit (PMU) driver support > >>>>>> for T-Head Yitian 710 SoC chip. Yitian 710 is based on the Synopsys PCI Express > >>>>>> Core controller IP which provides statistics feature. > > > >> ... > >> Really a question for Bjorn I think, but here is my 2 cents... > >> > >> The problem here is that we need to do that fundamental redesign of the > >> way the PCI ports drivers work. I'm not sure there is a path to merging > >> this until that is done. The bigger problem is that I'm not sure anyone > >> is actively looking at that yet. I'd like to look at this (as I have > >> the same problem for some other drivers), but it is behind various > >> other things on my todo list. > >> > >> Bjorn might be persuaded on a temporary solution, but that would come > >> with some maintenance problems, particularly when we try to do it > >> 'right' in the future. Maybe adding another service driver would be > >> a stop gap as long as we know we won't keep doing so for ever. Not sure. > > > > I think the question here is around the for_each_pci_dev() in > > __dwc_pcie_pmu_probe()? I don't *like* that because of the > > assumptions it breaks (autoload doesn't work, hotplug doesn't work), > > but: > > > > - There are several other drivers that also do this, > > - I don't have a better suggest for any of them, > > - It's not a drivers/pci thing, so not really up to me anyway, > > > > so I don't have any problem with this being merged as-is, as long as > > you can live with the limitations. > > > > I don't think this series does anything to work around those > > limitations, i.e., it doesn't make up fake device IDs for module > > loading or fake events for hotplug, so it seems like we could improve > > the implementation later if we ever have a way to do it. > > > > Bjorn > > + Will > > Ok, thank you for confirmation, Bjorn. Then it comes to perf driver parts and > it is really a question for @Will I think. > > What's your opinion about merging this patch set, @Will? No fundamental objection from me, but I'll have a closer look when you post a version addressing the feedback from Jonathan and Yicong. Cheers, Will
