IORESOURCE_ROM_SHADOW means there is a copy of a device's option ROM in
RAM.  The existence of such a copy and its location are arch-specific.
Previously the IORESOURCE_ROM_SHADOW flag was set in arch code, but the
0xC0000-0xDFFFF location was hard-coded into the PCI core.

If we're using a shadow copy in RAM, disable the ROM BAR and release the
address space it was consuming.  Move the location information from the PCI
core to the arch code that sets IORESOURCE_ROM_SHADOW.  Save the location
of the RAM copy in the struct resource for PCI_ROM_RESOURCE.

After this change, pci_map_rom() will call pci_assign_resource() and
pci_enable_rom() for these IORESOURCE_ROM_SHADOW resources, which we did
not do before.  This is safe because:

  - pci_assign_resource() will do nothing because the resource is marked
    IORESOURCE_PCI_FIXED, which means we can't move it, and

  - pci_enable_rom() will not turn on the ROM BAR's enable bit because the
    resource is marked IORESOURCE_ROM_SHADOW, which means it is in RAM
    rather than in PCI memory space.

Storing the location in the struct resource means "lspci" will show the
shadow location, not the value from the ROM BAR.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

A shadow copy of an option ROM is placed by the BIOS as a fixed address.
Set IORESOURCE_PCI_FIXED to indicate that we can't move the shadow copy.
This prevents warnings like the following when we assign resources:

  BAR 6: [??? 0x00000000 flags 0x2] has bogus alignment

This warning is emitted by pdev_sort_resources(), which already ignores
IORESOURCE_PCI_FIXED resources.

Link: http://lkml.kernel.org/r/CA+55aFyVMfTBB0oz_yx8+eQOEJnzGtCsYSj9QuhEpdZ9BHdq5A@mail.gmail.com
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Use common interface to simplify PCI host bridge implementation.

Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Use common struct resource_entry to replace private
struct iospace_resource.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Use common ACPI resource parsing interface to parse ACPI resources for
PCI host bridge, so we could share more code between IA64 and x86.
Later we will consolidate arch specific implementations into ACPI core.

Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Revert dff22d2054b5 ("PCI: Call pci_read_bridge_bases() from core instead
of arch code").

Reading PCI bridge windows is not arch-specific in itself, but there is PCI
core code that doesn't work correctly if we read them too early.  For
example, Hannes found this case on an ARM Freescale i.mx6 board:

  pci_bus 0000:00: root bus resource [mem 0x01000000-0x01efffff]
  pci 0000:00:00.0: PCI bridge to [bus 01-ff]
  pci 0000:00:00.0: BAR 8: no space for [mem size 0x01000000] (mem window)
  pci 0000:01:00.0: BAR 2: failed to assign [mem size 0x00200000]
  pci 0000:01:00.0: BAR 1: failed to assign [mem size 0x00004000]
  pci 0000:01:00.0: BAR 0: failed to assign [mem size 0x00000100]

The 00:00.0 mem window needs to be at least 3MB: the 01:00.0 device needs
0x204100 of space, and mem windows are megabyte-aligned.

Bus sizing can increase a bridge window size, but never *decrease* it (see
d65245c3297a ("PCI: don't shrink bridge resources")).  Prior to
dff22d2054b5, ARM didn't read bridge windows at all, so the "original size"
was zero, and we assigned a 3MB window.

After dff22d2054b5, we read the bridge windows before sizing the bus.  The
firmware programmed a 16MB window (size 0x01000000) in 00:00.0, and since
we never decrease the size, we kept 16MB even though we only needed 3MB.
But 16MB doesn't fit in the host bridge aperture, so we failed to assign
space for the window and the downstream devices.

I think this is a defect in the PCI core: we shouldn't rely on the firmware
to assign sensible windows.

Ray reported a similar problem, also on ARM, with Broadcom iProc.

Issues like this are too hard to fix right now, so revert dff22d2054b5.

Reported-by: Hannes <oe5hpm@gmail.com>
Reported-by: Ray Jui <rjui@broadcom.com>
Link: http://lkml.kernel.org/r/CAAa04yFQEUJm7Jj1qMT57-LG7ZGtnhNDBe=PpSRa70Mj+XhW-A@mail.gmail.com
Link: http://lkml.kernel.org/r/55F75BB8.4070405@broadcom.com
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

When we scan a PCI bus, we read PCI-PCI bridge window registers with
pci_read_bridge_bases() so we can validate the resource hierarchy.  Most
architectures call pci_read_bridge_bases() from pcibios_fixup_bus(), but
PCI-PCI bridges are not arch-specific, so this doesn't need to be in
arch-specific code.

Call pci_read_bridge_bases() directly from the PCI core instead of from
arch code.

For alpha and mips, we now call pci_read_bridge_bases() always; previously
we only called it if PCI_PROBE_ONLY was set.

[bhelgaas: changelog]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: James E.J. Bottomley <jejb@parisc-linux.org>
CC: Michael Ellerman <mpe@ellerman.id.au>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: David Howells <dhowells@redhat.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Tony Luck <tony.luck@intel.com>
CC: David S. Miller <davem@davemloft.net>
CC: Ingo Molnar <mingo@redhat.com>
CC: Guenter Roeck <linux@roeck-us.net>
CC: Michal Simek <monstr@monstr.eu>
CC: Chris Zankel <chris@zankel.net>

Commit 97badf873ab6 (device property: Make it possible to use
secondary firmware nodes) uncovered a bug in the x86 (and ia64) PCI
host bridge initialization code that assumes bridge->bus->sysdata
to always point to a struct pci_sysdata object which need not be
the case (in particular, the Xen PCI frontend driver sets it to point
to a different data type).  If it is not the case, an incorrect
pointer (or a piece of data that is not a pointer at all) will be
passed to ACPI_COMPANION_SET() and that may cause interesting
breakage to happen going forward.

To work around this problem use the observation that the ACPI
host bridge initialization always passes NULL as parent to
pci_create_root_bus(), so if pcibios_root_bridge_prepare() sees
a non-NULL parent of the bridge, it should not attempt to set
an ACPI companion for it, because that means that
pci_create_root_bus() has been called by someone else.

Fixes: 97badf873ab6 (device property: Make it possible to use secondary firmware nodes)
Reported-and-tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

Prior to c770cb4cb505 ("PCI: Mark invalid BARs as unassigned"), if we tried
to claim a PCI BAR but could not find an upstream bridge window that
matched it, we complained but still allowed the device to be enabled.

c770cb4cb505 broke devices that previously worked (mptsas and igb in the
case Tony reported, but it could be any devices) because it marks those
BARs as IORESOURCE_UNSET, which makes pci_enable_device() complain and
return failure:

  igb 0000:81:00.0: can't enable device: BAR 0 [mem size 0x00020000] not assigned
  igb: probe of 0000:81:00.0 failed with error -22

The underlying cause is an ACPI Address Space Descriptor for a PCI host
bridge window that is marked as "consumer".  This is a firmware defect:
resources that are produced on the downstream side of a bridge should be
marked "producer".  But rejecting these BARs that we previously allowed is
a functionality regression, and firmware has not used the producer/consumer
bit consistently, so we can't rely on it anyway.

Stop checking the producer/consumer bit, and assume all bridge Address
Space Descriptors are for bridge windows.

Note that this change does not affect I/O Port or Fixed Location I/O Port
Descriptors, which are commonly used for the [io 0x0cf8-0x0cff] config
access range.  That range is a "consumer" range and should not be treated
as a window.

Fixes: c770cb4cb505 ("PCI: Mark invalid BARs as unassigned")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=96961
Reported-and-tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

* acpica:
  ACPICA: Events: Enable APIs to allow interrupt/polling adaptive request based GPE handling model
  ACPICA: Events: Introduce acpi_set_gpe()/acpi_finish_gpe() to reduce divergences
  ACPICA: Events: Introduce ACPI_GPE_DISPATCH_RAW_HANDLER to fix 2 issues for the current GPE APIs
  ACPICA: Update version to 20150204
  ACPICA: Update Copyright headers to 2015
  ACPICA: Hardware: Cast GPE enable_mask before storing
  ACPICA: Events: Cleanup GPE dispatcher type obtaining code
  ACPICA: Events: Cleanup to move acpi_gbl_global_event_handler invocation out of acpi_ev_gpe_dispatch()
  ACPICA: Events: Cleanup of resetting the GPE handler to NULL before removing
  ACPICA: Events: Fix uninitialized variable
  ACPICA: Events: Remove acpi_ev_valid_gpe_event() due to current restriction
  ACPICA: Events: Remove duplicated sanity check in acpi_ev_enable_gpe()
  ACPICA: Events: Back port "ACPICA: Save current masks of enabled GPEs after enable register writes"
  ACPICA: Resources: Provide common part for struct acpi_resource_address structures.
  ACPI: Introduce acpi_unload_parent_table() usages in Linux kernel
  ACPICA: take ACPI_MTX_INTERPRETER in acpi_unload_table_id()