On Monday, January 28, 2013 01:56:33 PM Bjorn Helgaas wrote: > On Fri, Jan 18, 2013 at 9:07 AM, Jiang Liu <liu...@gmail.com> wrote: > > This is an RFC patchset to address review comments in thread at: > > https://patchwork.kernel.org/patch/1946851/. The patch just pasts > > compilation. If no objection to the new implementation, I will > > go on to modify acpiphp driver and conduct tests. > > > > The main changes from V4 to V5 includes: > > 1) introduce a dedicated notifier chain for PCI buses > > 2) change pci_slot as built-in driver > > 3) unify the way to create/destroy PCI slots > > 4) introduce a kernel option to disable PCIe native hotplug > > > > TODO: > > 1) change acpiphp as built-in and unify the way to create/destroy ACPI > > based hotplug slots. > > 2) change other ACPI PCI subdriver in Yinghai's root bridge hotplug series > > to use the PCI bus notifier chain. > > 3) Remove the ACPI PCI subdriver interface eventaully. > > > > Jiang Liu (8): > > PCI: make PCI device create/destroy logic symmetric > > PCI: split registration of PCI bus devices into two stages > > PCI: add a blocking notifier chain for PCI bus addition/removal > > ACPI, PCI: avoid building pci_slot as module > > PCI, ACPI: hook PCI bus notifications to create/destroy PCI slots > > pci_slot: replace printk(KERN_xxx) with pr_xxx() > > PCI/PCIe: add "pci=nopciehp" to disable PCIe native hotplug > > PCI/PCIe: only claim PME from firmware when CONFIG_PCIE_PME is > > enabled > > > > Documentation/kernel-parameters.txt | 2 + > > drivers/acpi/Kconfig | 5 +- > > drivers/acpi/internal.h | 5 + > > drivers/acpi/pci_root.c | 8 +- > > drivers/acpi/pci_slot.c | 217 > > ++++++++++------------------------- > > drivers/acpi/scan.c | 1 + > > drivers/pci/bus.c | 26 ++++- > > drivers/pci/pci.c | 2 + > > drivers/pci/pci.h | 1 + > > drivers/pci/pcie/portdrv_core.c | 7 +- > > drivers/pci/pcie/portdrv_pci.c | 3 + > > drivers/pci/probe.c | 7 +- > > drivers/pci/remove.c | 15 +-- > > include/linux/pci.h | 21 ++++ > > 14 files changed, 142 insertions(+), 178 deletions(-) > > I think the problem we're trying to solve is that we don't initialize > hot-added devices, correctly, e.g., we don't set up AER, we don't > update acpi/pci_slot stuff, we probably don't set up PME etc. We also > have similar issues like IOMMU init on powerpc. > > Notifier chains seem like an unnecessarily complicated way to deal > with this. They're great for communicating between modules that stay > at arm's length from each other. But that's not the case here -- > everything is PCI and is quite closely coupled. I think AER, PME, > slot, etc., should be initialized directly in pci_device_add() or > somewhere nearby.
I agree. > This might sound a bit radical because it implies some fairly > far-reaching changes. It means this code can't be a module (the only > one that can be built as a module today is pciehp, and I think > everybody agrees that we should make it static as soon as we can > figure out the acpiphp/pciehp issue). I think it also means the > pcieportdrv concept is of dubious value, since all the services should > be known at build-time and we probably don't need a registration > interface for them. It is of dubious value regardless. It just adds complexity for no gain. Moreover, these things are in fact not mutually independent. I've had a lot of headaches trying to work around that when I was working on PME support and later on _OSC for root bridges. Let's just take that stuff away once and for good. :-) Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
