[PATCH v2 00/29] Create PCI root buses with correct resources

From: Bjorn Helgaas
Date: Fri Oct 14 2011 - 00:27:17 EST


The most generic way to create a PCI root bus is with pci_scan_bus(), but
that doesn't allow you to specify what resources are available on the bus,
i.e., what the host bridge apertures are.

That means that pci_create_bus() has to fill in some incorrect defaults
(ioport_resource and iomem_resource), and the architecture has to fix
them later in pcibios_fixup_bus(). Between creation and fixup, we
run quirks, and they see the wrong bus resources:

pci_scan_bus or pci_scan_bus_parented
pci_create_bus <-- A create with default resources
pci_scan_child_bus
pci_scan_slot
pci_scan_single_device
pci_scan_device
pci_setup_device
pci_fixup_device(early) <-- B
pci_device_add
pci_fixup_device(header) <-- C
pcibios_fixup_bus <-- D fill in correct resources

Early and header quirks at B and C use the default (incorrect) root
bus resources rather than those filled in at D. If they request any
regions, they get the wrong parent. quirk_piix4_acpi() tripped over
this on MIPS and caused a driver to fail with unexpected conflicts
(http://www.spinics.net/lists/mips/msg41654.html).

A few architectures avoid this problem by using pci_create_bus()
directly and fixing the root bus resources before scanning the bus.
But that's ugly and is normally done because the arch needs a different
bus scanner, such as pci_of_scan_bus().

This series fixes the problem by adding new interfaces that take a list
of bus resources:

pci_scan_root_bus()
pci_create_root_bus()

To reduce backporting issues and remove cross-arch dependencies, I retained the
following interfaces unchanged, but marked them "deprecated."

pci_scan_bus()
pci_scan_bus_parented() (replace with pci_scan_root_bus/pci_scan_child_bus)
pci_create_bus()

I'm open to suggestions for improving pci_scan_root_bus(). For instance,
I wonder whether it should take a domain argument, so we could move some
of the PCI domain support into the core.

Changes since V1:
- left existing interfaces unchanged, but deprecated
- added pci_create_root_bus() and pci_scan_root_bus()
- fixed many more architectures

---

Bjorn Helgaas (29):
PCI: add helpers for building PCI bus resource lists
PCI: add pci_create_root_bus(), deprecate pci_create_bus()
PCI: add pci_scan_root_bus(), deprecate pci_scan_bus() and pci_scan_bus_parented()
MIPS: PCI: convert to pci_scan_root_bus() for correct root bus resources
x86/PCI: use pci_scan_bus() instead of pci_scan_bus_parented()
x86/PCI: convert to pci_create_root_bus() and pci_scan_root_bus()
powerpc/PCI: make pcibios_setup_phb_resources() static
powerpc/PCI: split PHB part out of pcibios_map_io_space()
powerpc/PCI: convert to pci_create_root_bus() for correct root bus resources
microblaze/PCI: fix pci_bus_for_each_resource() usage
microblaze/PCI: make pcibios_setup_phb_resources() static
microblaze/PCI: convert to pci_create_root_bus() for correct root bus resources
microblaze/PCI: use pci_scan_root_bus()
sparc/PCI: convert to pci_create_root_bus() for correct root bus resources
sparc32,leon/PCI: convert to pci_scan_root_bus() for correct root bus resources
ia64/PCI: use pci_create_bus() instead of pci_scan_bus_parented()
ia64/PCI: convert to pci_create_root_bus() for correct root bus resources
parisc/PCI: use pci_create_root_bus() instead of pci_scan_bus_parented()
parisc/PCI: supply root bus resources to pci_create_root_bus()
parisc/PCI: deal with LMMIO/PAT overlaps before creating PCI root bus
parisc/PCI: use pci_create_root_bus() instead of pci_scan_bus_parented()
parisc/PCI: supply root bus resources to pci_create_root_bus()
xen/PCI: use pci_create_root_bus() instead of pci_scan_bus_parented()
alpha/PCI: convert to pci_scan_root_bus() for correct root bus resources
arm/PCI: convert to pci_scan_root_bus() for correct root bus resources
frv/PCI: convert to pci_scan_root_bus() for correct root bus resources
mn10300/PCI: convert to pci_scan_root_bus() for correct root bus resources
sh/PCI: convert to pci_scan_root_bus() for correct root bus resources
xtensa/PCI: convert to pci_scan_root_bus() for correct root bus resources


arch/alpha/kernel/pci.c | 37 +++++++------
arch/arm/common/it8152.c | 6 +-
arch/arm/common/via82c505.c | 3 +
arch/arm/include/asm/mach/pci.h | 2 -
arch/arm/kernel/bios32.c | 27 +++-------
arch/arm/mach-cns3xxx/pcie.c | 8 +--
arch/arm/mach-dove/pcie.c | 9 +--
arch/arm/mach-footbridge/dc21285.c | 8 +--
arch/arm/mach-integrator/pci_v3.c | 19 ++++---
arch/arm/mach-iop13xx/pci.c | 17 +++---
arch/arm/mach-ixp2000/enp2611.c | 3 +
arch/arm/mach-ixp2000/pci.c | 8 +--
arch/arm/mach-ixp23xx/pci.c | 8 +--
arch/arm/mach-ixp4xx/common-pci.c | 8 +--
arch/arm/mach-kirkwood/pcie.c | 8 +--
arch/arm/mach-ks8695/pci.c | 8 +--
arch/arm/mach-mv78xx0/pcie.c | 8 +--
arch/arm/mach-orion5x/pci.c | 16 +++---
arch/arm/mach-sa1100/pci-nanoengine.c | 9 ++-
arch/arm/mach-tegra/pcie.c | 9 ++-
arch/arm/mach-versatile/pci.c | 19 ++++---
arch/arm/plat-iop/pci.c | 8 +--
arch/frv/mb93090-mb00/pci-vdk.c | 26 +++++++--
arch/ia64/pci/pci.c | 40 ++++++--------
arch/microblaze/include/asm/pci-bridge.h | 1
arch/microblaze/pci/pci-common.c | 39 ++++++--------
arch/mips/pci/pci.c | 18 ++++--
arch/mn10300/unit-asb2305/pci.c | 14 +++--
arch/powerpc/include/asm/pci-bridge.h | 1
arch/powerpc/kernel/pci-common.c | 27 ++++++----
arch/powerpc/kernel/pci_64.c | 40 +++++++-------
arch/sh/drivers/pci/pci.c | 19 ++++---
arch/sparc/kernel/leon_pci.c | 26 +++------
arch/sparc/kernel/pci.c | 18 ++----
arch/x86/include/asm/topology.h | 2 -
arch/x86/pci/acpi.c | 31 ++++++-----
arch/x86/pci/bus_numa.c | 31 ++++++-----
arch/x86/pci/common.c | 21 +++++--
arch/x86/pci/legacy.c | 3 -
arch/x86/pci/numaq_32.c | 2 -
arch/xtensa/kernel/pci.c | 85 +++++++++++++++---------------
drivers/parisc/dino.c | 48 ++++++++---------
drivers/parisc/lba_pci.c | 73 ++++++++++++++------------
drivers/pci/bus.c | 30 +++++++++--
drivers/pci/probe.c | 75 ++++++++++++++++++++++++--
drivers/pci/xen-pcifront.c | 7 +-
include/linux/pci.h | 24 +++++---
47 files changed, 522 insertions(+), 427 deletions(-)

--
Bjorn
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