<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/drivers/pci, branch v4.3-rc4</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge branches 'pm-pci' and 'acpi-pci'</title>
<updated>2015-10-01T20:30:12+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2015-10-01T20:30:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dd953d318daad9a3c1f9a6bf31430bf40163051e'/>
<id>dd953d318daad9a3c1f9a6bf31430bf40163051e</id>
<content type='text'>
* pm-pci:
  PCI / PM: Update runtime PM documentation for PCI devices

* acpi-pci:
  ACPI / PCI: Remove duplicated penalty on SCI IRQ
  ACPI, PCI, irq: Do not share PCI IRQ with ISA IRQ
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* pm-pci:
  PCI / PM: Update runtime PM documentation for PCI devices

* acpi-pci:
  ACPI / PCI: Remove duplicated penalty on SCI IRQ
  ACPI, PCI, irq: Do not share PCI IRQ with ISA IRQ
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'pci-v4.3-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci</title>
<updated>2015-09-25T18:16:53+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-09-25T18:16:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=966966a630d936310ebb0f9bfe9e23a662d00454'/>
<id>966966a630d936310ebb0f9bfe9e23a662d00454</id>
<content type='text'>
Pull PCI fixes from Bjorn Helgaas:
 "These are fixes for things we merged for v4.3 (VPD, MSI, and bridge
  window management), and a new Renesas R8A7794 SoC device ID.

  Details:

  Resource management:
   - Revert pci_read_bridge_bases() unification (Bjorn Helgaas)
   - Clear IORESOURCE_UNSET when clipping a bridge window (Bjorn
     Helgaas)

  MSI:
   - Fix MSI IRQ domains for VFs on virtual buses (Alex Williamson)

  Renesas R-Car host bridge driver:
   - Add R8A7794 support (Sergei Shtylyov)

  Miscellaneous:
   - Fix devfn for VPD access through function 0 (Alex Williamson)
   - Use function 0 VPD only for identical functions (Alex Williamson)"

* tag 'pci-v4.3-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: rcar: Add R8A7794 support
  PCI: Use function 0 VPD for identical functions, regular VPD for others
  PCI: Fix devfn for VPD access through function 0
  PCI/MSI: Fix MSI IRQ domains for VFs on virtual buses
  PCI: Clear IORESOURCE_UNSET when clipping a bridge window
  PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code"
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull PCI fixes from Bjorn Helgaas:
 "These are fixes for things we merged for v4.3 (VPD, MSI, and bridge
  window management), and a new Renesas R8A7794 SoC device ID.

  Details:

  Resource management:
   - Revert pci_read_bridge_bases() unification (Bjorn Helgaas)
   - Clear IORESOURCE_UNSET when clipping a bridge window (Bjorn
     Helgaas)

  MSI:
   - Fix MSI IRQ domains for VFs on virtual buses (Alex Williamson)

  Renesas R-Car host bridge driver:
   - Add R8A7794 support (Sergei Shtylyov)

  Miscellaneous:
   - Fix devfn for VPD access through function 0 (Alex Williamson)
   - Use function 0 VPD only for identical functions (Alex Williamson)"

* tag 'pci-v4.3-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: rcar: Add R8A7794 support
  PCI: Use function 0 VPD for identical functions, regular VPD for others
  PCI: Fix devfn for VPD access through function 0
  PCI/MSI: Fix MSI IRQ domains for VFs on virtual buses
  PCI: Clear IORESOURCE_UNSET when clipping a bridge window
  PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code"
</pre>
</div>
</content>
</entry>
<entry>
<title>PCI / PM: Update runtime PM documentation for PCI devices</title>
<updated>2015-09-25T00:48:44+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2015-09-18T01:08:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a8360062ccfb4b891d3013d0e55826c8bcb02bfb'/>
<id>a8360062ccfb4b891d3013d0e55826c8bcb02bfb</id>
<content type='text'>
Section 3.2 "Device Runtime Power Management" of pci.txt has become
outdated, so update it to correctly reflect the current code flow.

Also update the comment in local_pci_probe() to document the fact
that pm_runtime_put_noidle() is not the only runtime PM helper
function that can be used to decrement the device's runtime PM
usage counter in .probe().

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Section 3.2 "Device Runtime Power Management" of pci.txt has become
outdated, so update it to correctly reflect the current code flow.

Also update the comment in local_pci_probe() to document the fact
that pm_runtime_put_noidle() is not the only runtime PM helper
function that can be used to decrement the device's runtime PM
usage counter in .probe().

Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: rcar: Add R8A7794 support</title>
<updated>2015-09-24T22:06:32+00:00</updated>
<author>
<name>Sergei Shtylyov</name>
<email>sergei.shtylyov@cogentembedded.com</email>
</author>
<published>2015-09-11T23:06:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=de24c18c0faca5ebd618e1cb87f5489745e40475'/>
<id>de24c18c0faca5ebd618e1cb87f5489745e40475</id>
<content type='text'>
Add Renesas R8A7794 SoC support to the Renesas R-Car gen2 PCI driver.

Signed-off-by: Sergei Shtylyov &lt;sergei.shtylyov@cogentembedded.com&gt;
Signed-off-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Acked-by: Simon Horman &lt;horms+renesas@verge.net.au&gt;</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add Renesas R8A7794 SoC support to the Renesas R-Car gen2 PCI driver.

Signed-off-by: Sergei Shtylyov &lt;sergei.shtylyov@cogentembedded.com&gt;
Signed-off-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Acked-by: Simon Horman &lt;horms+renesas@verge.net.au&gt;</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: Use function 0 VPD for identical functions, regular VPD for others</title>
<updated>2015-09-24T22:06:32+00:00</updated>
<author>
<name>Alex Williamson</name>
<email>alex.williamson@redhat.com</email>
</author>
<published>2015-09-16T04:24:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=da2d03ea27f6ed9d2005a67b20dd021ddacf1e4d'/>
<id>da2d03ea27f6ed9d2005a67b20dd021ddacf1e4d</id>
<content type='text'>
932c435caba8 ("PCI: Add dev_flags bit to access VPD through function 0")
added PCI_DEV_FLAGS_VPD_REF_F0.  Previously, we set the flag on every
non-zero function of quirked devices.  If a function turned out to be
different from function 0, i.e., it had a different class, vendor ID, or
device ID, the flag remained set but we didn't make VPD accessible at all.

Flip this around so we only set PCI_DEV_FLAGS_VPD_REF_F0 for functions that
are identical to function 0, and allow regular VPD access for any other
functions.

[bhelgaas: changelog, stable tag]
Fixes: 932c435caba8 ("PCI: Add dev_flags bit to access VPD through function 0")
Signed-off-by: Alex Williamson &lt;alex.williamson@redhat.com&gt;
Signed-off-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Acked-by: Myron Stowe &lt;myron.stowe@redhat.com&gt;
Acked-by: Mark Rustad &lt;mark.d.rustad@intel.com&gt;
CC: stable@vger.kernel.org</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
932c435caba8 ("PCI: Add dev_flags bit to access VPD through function 0")
added PCI_DEV_FLAGS_VPD_REF_F0.  Previously, we set the flag on every
non-zero function of quirked devices.  If a function turned out to be
different from function 0, i.e., it had a different class, vendor ID, or
device ID, the flag remained set but we didn't make VPD accessible at all.

Flip this around so we only set PCI_DEV_FLAGS_VPD_REF_F0 for functions that
are identical to function 0, and allow regular VPD access for any other
functions.

[bhelgaas: changelog, stable tag]
Fixes: 932c435caba8 ("PCI: Add dev_flags bit to access VPD through function 0")
Signed-off-by: Alex Williamson &lt;alex.williamson@redhat.com&gt;
Signed-off-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Acked-by: Myron Stowe &lt;myron.stowe@redhat.com&gt;
Acked-by: Mark Rustad &lt;mark.d.rustad@intel.com&gt;
CC: stable@vger.kernel.org</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: Fix devfn for VPD access through function 0</title>
<updated>2015-09-24T22:06:32+00:00</updated>
<author>
<name>Alex Williamson</name>
<email>alex.williamson@redhat.com</email>
</author>
<published>2015-09-15T17:17:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9d9240756e63dd87d6cbf5da8b98ceb8f8192b55'/>
<id>9d9240756e63dd87d6cbf5da8b98ceb8f8192b55</id>
<content type='text'>
Commit 932c435caba8 ("PCI: Add dev_flags bit to access VPD through function
0") passes PCI_SLOT(devfn) for the devfn parameter of pci_get_slot().
Generally this works because we're fairly well guaranteed that a PCIe
device is at slot address 0, but for the general case, including
conventional PCI, it's incorrect.  We need to get the slot and then convert
it back into a devfn.

Fixes: 932c435caba8 ("PCI: Add dev_flags bit to access VPD through function 0")
Signed-off-by: Alex Williamson &lt;alex.williamson@redhat.com&gt;
Signed-off-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Acked-by: Myron Stowe &lt;myron.stowe@redhat.com&gt;
Acked-by: Mark Rustad &lt;mark.d.rustad@intel.com&gt;
CC: stable@vger.kernel.org</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 932c435caba8 ("PCI: Add dev_flags bit to access VPD through function
0") passes PCI_SLOT(devfn) for the devfn parameter of pci_get_slot().
Generally this works because we're fairly well guaranteed that a PCIe
device is at slot address 0, but for the general case, including
conventional PCI, it's incorrect.  We need to get the slot and then convert
it back into a devfn.

Fixes: 932c435caba8 ("PCI: Add dev_flags bit to access VPD through function 0")
Signed-off-by: Alex Williamson &lt;alex.williamson@redhat.com&gt;
Signed-off-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Acked-by: Myron Stowe &lt;myron.stowe@redhat.com&gt;
Acked-by: Mark Rustad &lt;mark.d.rustad@intel.com&gt;
CC: stable@vger.kernel.org</pre>
</div>
</content>
</entry>
<entry>
<title>PCI/MSI: Fix MSI IRQ domains for VFs on virtual buses</title>
<updated>2015-09-24T22:06:32+00:00</updated>
<author>
<name>Alex Williamson</name>
<email>alex.williamson@redhat.com</email>
</author>
<published>2015-09-18T21:08:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=38ea72bdb65df2f40ec77b2c9d1413e7f5e34465'/>
<id>38ea72bdb65df2f40ec77b2c9d1413e7f5e34465</id>
<content type='text'>
SR-IOV creates a virtual bus where bus-&gt;self is NULL.  When we add VFs and
scan for an MSI domain, pci_set_bus_msi_domain() dereferences bus-&gt;self,
which causes a kernel NULL pointer dereference oops.

Scan up to the parent bus until we find a real bridge where we can get the
MSI domain.

[bhelgaas: changelog]
Fixes: 44aa0c657e3e ("PCI/MSI: Add hooks to populate the msi_domain field")
Tested-by: Joerg Roedel &lt;joro@8bytes.org&gt;
Signed-off-by: Alex Williamson &lt;alex.williamson@redhat.com&gt;
Signed-off-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Acked-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
SR-IOV creates a virtual bus where bus-&gt;self is NULL.  When we add VFs and
scan for an MSI domain, pci_set_bus_msi_domain() dereferences bus-&gt;self,
which causes a kernel NULL pointer dereference oops.

Scan up to the parent bus until we find a real bridge where we can get the
MSI domain.

[bhelgaas: changelog]
Fixes: 44aa0c657e3e ("PCI/MSI: Add hooks to populate the msi_domain field")
Tested-by: Joerg Roedel &lt;joro@8bytes.org&gt;
Signed-off-by: Alex Williamson &lt;alex.williamson@redhat.com&gt;
Signed-off-by: Bjorn Helgaas &lt;helgaas@kernel.org&gt;
Acked-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: Clear IORESOURCE_UNSET when clipping a bridge window</title>
<updated>2015-09-22T22:03:54+00:00</updated>
<author>
<name>Bjorn Helgaas</name>
<email>bhelgaas@google.com</email>
</author>
<published>2015-09-22T22:03:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b838b39e930aa1cfd099ea82ac40ed6d6413af26'/>
<id>b838b39e930aa1cfd099ea82ac40ed6d6413af26</id>
<content type='text'>
c770cb4cb505 ("PCI: Mark invalid BARs as unassigned") sets IORESOURCE_UNSET
if we fail to claim a resource.  If we tried to claim a bridge window,
failed, clipped the window, and tried to claim the clipped window, we
failed again because of IORESOURCE_UNSET:

  pci_bus 0000:00: root bus resource [mem 0xc0000000-0xffffffff window]
  pci 0000:00:01.0: can't claim BAR 15 [mem 0xbdf00000-0xddefffff 64bit pref]: no compatible bridge window
  pci 0000:00:01.0: [mem size 0x20000000 64bit pref] clipped to [mem size 0x1df00000 64bit pref]
  pci 0000:00:01.0:   bridge window [mem size 0x1df00000 64bit pref]
  pci 0000:00:01.0: can't claim BAR 15 [mem size 0x1df00000 64bit pref]: no address assigned

The 00:01.0 window started as [mem 0xbdf00000-0xddefffff 64bit pref].  That
starts before the host bridge window [mem 0xc0000000-0xffffffff window], so
we clipped the 00:01.0 window to [mem 0xc0000000-0xddefffff 64bit pref].
But we left it marked IORESOURCE_UNSET, so the second claim failed when it
should have succeeded.

This means downstream devices will also fail for lack of resources, e.g.,
in the bugzilla below,

  radeon 0000:01:00.0: Fatal error during GPU init

Clear IORESOURCE_UNSET when we clip a bridge window.  Also clear
IORESOURCE_UNSET in our copy of the unclipped window so we can see exactly
what the original window was and how it now fits inside the upstream
window.

Fixes: c770cb4cb505 ("PCI: Mark invalid BARs as unassigned")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491#c47
Based-on-patch-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Based-on-patch-by: Yinghai Lu &lt;yinghai@kernel.org&gt;
Tested-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Reviewed-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Acked-by: Yinghai Lu &lt;yinghai@kernel.org&gt;
CC: stable@vger.kernel.org	# v4.1+</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
c770cb4cb505 ("PCI: Mark invalid BARs as unassigned") sets IORESOURCE_UNSET
if we fail to claim a resource.  If we tried to claim a bridge window,
failed, clipped the window, and tried to claim the clipped window, we
failed again because of IORESOURCE_UNSET:

  pci_bus 0000:00: root bus resource [mem 0xc0000000-0xffffffff window]
  pci 0000:00:01.0: can't claim BAR 15 [mem 0xbdf00000-0xddefffff 64bit pref]: no compatible bridge window
  pci 0000:00:01.0: [mem size 0x20000000 64bit pref] clipped to [mem size 0x1df00000 64bit pref]
  pci 0000:00:01.0:   bridge window [mem size 0x1df00000 64bit pref]
  pci 0000:00:01.0: can't claim BAR 15 [mem size 0x1df00000 64bit pref]: no address assigned

The 00:01.0 window started as [mem 0xbdf00000-0xddefffff 64bit pref].  That
starts before the host bridge window [mem 0xc0000000-0xffffffff window], so
we clipped the 00:01.0 window to [mem 0xc0000000-0xddefffff 64bit pref].
But we left it marked IORESOURCE_UNSET, so the second claim failed when it
should have succeeded.

This means downstream devices will also fail for lack of resources, e.g.,
in the bugzilla below,

  radeon 0000:01:00.0: Fatal error during GPU init

Clear IORESOURCE_UNSET when we clip a bridge window.  Also clear
IORESOURCE_UNSET in our copy of the unclipped window so we can see exactly
what the original window was and how it now fits inside the upstream
window.

Fixes: c770cb4cb505 ("PCI: Mark invalid BARs as unassigned")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491#c47
Based-on-patch-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Based-on-patch-by: Yinghai Lu &lt;yinghai@kernel.org&gt;
Tested-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Reviewed-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;
Acked-by: Yinghai Lu &lt;yinghai@kernel.org&gt;
CC: stable@vger.kernel.org	# v4.1+</pre>
</div>
</content>
</entry>
<entry>
<title>genirq: Remove irq argument from irq flow handlers</title>
<updated>2015-09-16T13:47:51+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2015-09-14T08:42:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bd0b9ac405e1794d72533c3d487aa65b6b955a0c'/>
<id>bd0b9ac405e1794d72533c3d487aa65b6b955a0c</id>
<content type='text'>
Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.

Remove the argument.

Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Julia Lawall &lt;Julia.Lawall@lip6.fr&gt;
Cc: Jiang Liu &lt;jiang.liu@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.

Remove the argument.

Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Julia Lawall &lt;Julia.Lawall@lip6.fr&gt;
Cc: Jiang Liu &lt;jiang.liu@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code"</title>
<updated>2015-09-15T18:18:04+00:00</updated>
<author>
<name>Bjorn Helgaas</name>
<email>bhelgaas@google.com</email>
</author>
<published>2015-09-15T18:18:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=237865f195f6b10e4724ce49eeb3972641da882a'/>
<id>237865f195f6b10e4724ce49eeb3972641da882a</id>
<content type='text'>
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 &lt;oe5hpm@gmail.com&gt;
Reported-by: Ray Jui &lt;rjui@broadcom.com&gt;
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 &lt;bhelgaas@google.com&gt;
Acked-by: Yinghai Lu &lt;yinghai@kernel.org&gt;
Acked-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;</content>
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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 &lt;oe5hpm@gmail.com&gt;
Reported-by: Ray Jui &lt;rjui@broadcom.com&gt;
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 &lt;bhelgaas@google.com&gt;
Acked-by: Yinghai Lu &lt;yinghai@kernel.org&gt;
Acked-by: Lorenzo Pieralisi &lt;lorenzo.pieralisi@arm.com&gt;</pre>
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