[PATCH] PCI bus number management
Thomas Hoffmann
trh411 at gmail.com
Thu Feb 6 19:47:10 UTC 2014
On Thu, Feb 6, 2014 at 2:37 PM, John Baldwin <jhb at freebsd.org> wrote:
> I have a patch to teach the PCI bus code and PCI-PCI bridge driver to
> manage
> PCI bus numbers. The approach is somewhat similar to how NEW_PCIB manages
> I/O
> windows for briges. Each bridge creates an rman to manage the bus numbers
> for
> all buses and bridges that live below it. Each bus allocates a bus
> resource
> from its parent bridge, and child bridges allocate their ranges from their
> parent devices. At the "top" of the PCI tree, the Host-PCI bridges
> allocate
> their respective bus ranges from their PCI domain/segment. There isn't
> really
> a device node for PCI domains, so I created a helper API that basically
> auto-
> creates a PCI bus rman for each domain on first use and then sub-allocates
> from that for Host-PCI bridges.
>
> The current patch (with some extra debugging) is at
> http://people.FreeBSD.org/~jhb/patches/pci_bus_rman.3.patch
>
> I would like to commit this to HEAD soon but thought I would post it for
> some
> pre-commit testing for the brave. :) If you are really brave, try booting
> with 'hw.pci.clear_buses=1' which will force the kernel to renumber all
> buses
> in the system. If you are really, really brave, try booting with
> 'hw.pci.clear_bars=1', 'hw.pci.clear_buses=1', and 'hw.pci.clear_pcib=1'.
> (My
> laptop survives with all those set)
>
> Note that the patch only enables bus number management on amd64 and i386.
> I
> believe ia64 just needs to define PCI_RES_BUS for this to work since it
> mandates ACPI. Porting this to other platforms requires handling
> PCI_RES_BUS
> rseources for Host-PCI bridges in bus_alloc_resource(),
> bus_adjust_resource(),
> and bus_release_resource().
>
> --
> John Baldwin
>
I get a "404 - Not Found" trying to follow the link.
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