Re: [PATCH v5 0/5] PCI: try "pci=use_crs" again
From: Jesse Barnes
Date: Tue Feb 23 2010 - 13:06:36 EST
On Tue, 23 Feb 2010 10:24:15 -0700
Bjorn Helgaas <bjorn.helgaas@xxxxxx> wrote:
> Historically, Linux has assumed a single PCI host bridge, with that
> bridge claiming all the address space left after RAM and legacy
> devices are taken out.
>
> If the system contains multiple host bridges, we can no longer
> operate under that assumption. We have to know what parts of the
> address space are claimed by each bridge so that when we assign
> resources to a PCI device, we take them from a range claimed by the
> upstream host bridge.
>
> On x86 and ia64, we use ACPI to enumerate all the PCI host bridges in
> the system, and part of the host bridge description is the
> "_CRS" (current resource settings" property, which lists the address
> space used by the bridge. On x86, we currently ignore most of the
> _CRS information. This patch series changes this, so we will use
> _CRS to learn about the host bridge windows.
>
> Since most x86 machines with multiple host bridges are relatively
> new, this series only turns this on for machines with BIOS dates of
> 2008 or newer.
>
> Changes from v4 to v5:
> - Add EXPORT_SYMBOL_GPL(pci_bus_resource_n) for module builds.
Thanks, it built this time. Pushed to my linux-next branch.
--
Jesse Barnes, Intel Open Source Technology Center
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/