Commit Graph

226 Commits

Author SHA1 Message Date
Bjorn Helgaas 5632e2beaf Revert "PCI: Distribute available resources for root buses, too"
This reverts commit e96e27fc6f.

Jonathan reported that this commit broke this topology, where all the space
available on bus 02 was assigned to the 02:00.0 bridge window, leaving none
for the e1000 device at 02:00.1:

  pci 0000:00:04.0: bridge window [mem 0x10200000-0x103fffff] to [bus 02-04]
  pci 0000:02:00.0: bridge window [mem 0x10200000-0x103fffff] to [bus 03-04]
  pci 0000:02:00.1: BAR 0: failed to assign [mem size 0x00020000]
  e1000 0000:02:00.1: can't ioremap BAR 0: [??? 0x00000000 flags 0x0]

Link: https://lore.kernel.org/r/20221014124553.0000696f@huawei.com
Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-10-14 14:27:58 -05:00
Mika Westerberg 17d2d67d76 PCI: Fix whitespace and indentation
Drop two empty lines from pci_scan_child_bus_extend() and correct
indentation in pci_bridge_distribute_available_resources() to better
follow the kernel coding style.

No functional impact.

Link: https://lore.kernel.org/r/20220905080232.36087-6-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2022-09-21 14:50:35 -05:00
Mika Westerberg e96e27fc6f PCI: Distribute available resources for root buses, too
Previously we distributed spare resources only upon hot-add, so if the
initial root bus scan found devices that had not been fully configured by
the BIOS, we allocated only enough resources to cover what was then
present. If some of those devices were hotplug bridges, we did not leave
any additional resource space for future expansion.

Distribute the available resources for root buses, too, to make this work
the same way as the normal hotplug case.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216000
Link: https://lore.kernel.org/r/20220905080232.36087-5-mika.westerberg@linux.intel.com
Reported-by: Chris Chiu <chris.chiu@canonical.com>
Tested-by: Chris Chiu <chris.chiu@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2022-09-21 14:47:07 -05:00
Mika Westerberg d1caf229c7 PCI: Move pci_assign_unassigned_root_bus_resources()
We need to be able to call pci_bridge_distribute_available_resources()
from this function so move it accordingly to avoid need for forward
declaration.

No functional impact.

Link: https://lore.kernel.org/r/20220905080232.36087-4-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2022-09-21 14:46:59 -05:00
Bjorn Helgaas 73c82469bd Merge branch 'pci/misc'
- Update the aer-inject URL (Yicong Yang)

- Declare pci_filp_private only when HAVE_PCI_MMAP to avoid unused struct
  definition (Krzysztof Wilczyński)

- Remove unused assignments (Bjorn Helgaas)

- Add #includes to asm/pci_x86.h to prevent build errors (Randy Dunlap)

* pci/misc:
  x86/PCI: Add #includes to asm/pci_x86.h
  PCI: ibmphp: Remove unused assignments
  PCI: cpqphp: Remove unused assignments
  PCI: fu740: Remove unused assignments
  PCI: kirin: Remove unused assignments
  PCI: Remove unused assignments
  PCI: Declare pci_filp_private only when HAVE_PCI_MMAP
  PCI/AER: Update aer-inject URL
2022-03-22 17:16:21 -05:00
Bjorn Helgaas c50762a85d PCI: Remove unused assignments
Remove variables and assignments that are never used.

Found by Krzysztof using cppcheck, e.g.,

  $ cppcheck --enable=all --force
  uselessAssignmentPtrArg drivers/pci/proc.c:102 Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?
  unreadVariable drivers/pci/setup-bus.c:1528 Variable 'old_flags' is assigned a value that is never used.

Reported-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20220313192933.434746-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-03-22 11:23:53 -05:00
Dongdong Liu 3dc8a1f6f6 PCI: Support BAR sizes up to 8TB
Current kernel reports that BARs larger than 128GB, e.g., this 4TB BAR, are
disabled:

    pci 0000:01:00.0: disabling BAR 4: [mem 0x00000000-0x3ffffffffff 64bit pref] (bad alignment 0x40000000000)

Increase the maximum BAR size from 128GB to 8TB for future expansion.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20220118092117.10089-1-liudongdong3@huawei.com
Signed-off-by: Dongdong Liu <liudongdong3@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-03-03 12:11:15 -06:00
Krzysztof Wilczyński fd1ae23b49 PCI: Prefer 'unsigned int' over bare 'unsigned'
The bare "unsigned" type implicitly means "unsigned int", but the preferred
coding style is to use the complete type name.

Update the bare use of "unsigned" to the preferred "unsigned int".

No change to functionality intended.

See a1ce18e4f9 ("checkpatch: warn on bare unsigned or signed declarations
without int").

Link: https://lore.kernel.org/r/20211013014136.1117543-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2021-10-27 13:41:22 -05:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Bjorn Helgaas 65c2bc6ce9 Merge branch 'pci/doc'
- Fix several kerneldoc warnings (Krzysztof Kozlowski)

* pci/doc:
  PCI: Fix kerneldoc warnings
2020-08-05 18:24:22 -05:00
Krzysztof Kozlowski 9b41d19aff PCI: Fix kerneldoc warnings
Fix kerneldoc warnings, e.g.,

  $ make W=1 drivers/pci/
  drivers/pci/ats.c:196: warning: Function parameter or member 'pdev' not described in 'pci_enable_pri'
  drivers/pci/ats.c:196: warning: Function parameter or member 'reqs' not described in 'pci_enable_pri'
  ...

Link: https://lore.kernel.org/r/20200729201224.26799-2-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-3-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-4-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-5-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-6-krzk@kernel.org
Link: https://lore.kernel.org/r/20200729201224.26799-7-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-08-05 18:23:14 -05:00
Liao Pingfang c7c337c5ed PCI: Fix error in panic message
Use kzalloc() instead of kmalloc() in the panic message.

[bhelgaas: drop similar ibmphp_pci.c change since it's not obviously
correct]
Link: https://lore.kernel.org/r/1594279708-34369-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-07-09 16:01:09 -05:00
Bjorn Helgaas d388e541e2 Merge branch 'remotes/lorenzo/pci/host-generic'
- Constify struct pci_ecam_ops (Rob Herring)

  - Support building as modules (Rob Herring)

  - Eliminate wrappers for pci_host_common_probe() by using DT match table
    data (Rob Herring)

* remotes/lorenzo/pci/host-generic:
  PCI: host-generic: Eliminate pci_host_common_probe wrappers
  PCI: host-generic: Support building as modules
  PCI: Constify struct pci_ecam_ops

# Conflicts:
#	drivers/pci/controller/dwc/pcie-hisi.c
2020-06-04 12:59:16 -05:00
Krzysztof Wilczynski 6e0688dbff PCI: Use bridge window names (PCI_BRIDGE_IO_WINDOW etc)
Use bridge resource definitions instead of using the PCI_BRIDGE_RESOURCES
constant with an integer offeset.

Link: https://lore.kernel.org/r/20200520183411.1534621-2-kw@linux.com
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-05-21 15:53:07 -05:00
Rob Herring 0c59c06a7c PCI: host-generic: Support building as modules
Enable building host-generic and its host-common dependency as a
module.

Link: https://lore.kernel.org/r/20200409234923.21598-3-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Andrew Murray <amurray@thegoodpenguin.co.uk>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-pci@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
2020-05-01 16:29:27 +01:00
Ivan Kokshaysky 2c8d5a2dc1 PCI: Add support for root bus sizing
In certain cases we should be able to enumerate IO and MEM ranges of all
PCI devices installed in the system, and then set respective host bridge
apertures basing on calculated size and alignment.  Particularly when
firmware is broken and fails to assign bridge windows properly, like on
Alpha UP1500 platform.

Actually, almost everything is already in place, and required changes are
minimal:

- add "size_windows" flag to struct pci_host_bridge: when set, it
  instructs __pci_bus_size_bridges() to continue with the root bus;
- in the __pci_bus_size_bridges() path: add checks for bus->self,
  as it can legitimately be null for the root bus.

Link: https://lore.kernel.org/r/20200314194355.GA12510@mail.rc.ru
Tested-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-03-30 09:52:34 -05:00
Nicholas Johnson 948675736a PCI: Allow adjust_bridge_window() to shrink resource if necessary
Remove checks for resource size in adjust_bridge_window(). This is
necessary to allow pci_bus_distribute_available_resources() to function
when the kernel parameter "pci=hpmemsize=nn[KMG]" is used to allocate
resources. Because the kernel parameter sets the size of all hotplug
bridges to be the same, there are problems when nested hotplug bridges are
encountered. Fitting a downstream hotplug bridge with size X and normal
bridges with non-zero size Y into parent hotplug bridge with size X is
impossible, and hence the downstream hotplug bridge needs to shrink to fit
into its parent.

Add check for if bridge is extended or shrunken and reflect that in the
call to pci_dbg().

Reset the resource if its new size is zero (if we have run out of a bridge
window resource) to prevent the PCI resource assignment code from
attempting to assign a zero-sized resource.

Link: https://lore.kernel.org/r/PSXP216MB0438D3E2CFE64EBAA32AF691803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 16:57:28 -06:00
Nicholas Johnson ae4611f1d7 PCI: Set resource size directly in adjust_bridge_window()
Change adjust_bridge_window() to set resource size directly instead of
using additional resource lists.

Because additional resource lists are optional resources, any algorithm
that requires guaranteed allocation that uses them cannot be guaranteed to
work.

Remove the resource from add_list, as a zero-sized additional resource is
redundant.

Update comment in pci_bus_distribute_available_resources() to reflect the
above changes.

Link: https://lore.kernel.org/r/PSXP216MB04386BA48874B56BC5CB0292803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 16:57:28 -06:00
Nicholas Johnson 1e58f4e1cb PCI: Rename extend_bridge_window() to adjust_bridge_window()
Rename extend_bridge_window() to adjust_bridge_window() to prepare for the
fact that the window will be able to shrink.  No functional change
intended.

Link: https://lore.kernel.org/r/PSXP216MB0438C47B3473D0C9DE531F18803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 16:57:28 -06:00
Nicholas Johnson 3d264da9b7 PCI: Rename extend_bridge_window() parameter
In extend_bridge_window(), change "available" parameter name to "new_size".
This makes more sense as this parameter represents the new size for the
window.  No functional change intended.

Link: https://lore.kernel.org/r/PSXP216MB043853617ECA4118C472A417803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 16:57:28 -06:00
Nicholas Johnson f924c26e4e PCI: Consider alignment of hot-added bridges when assigning resources
Change pci_bus_distribute_available_resources() to better handle bridges
with different resource alignment requirements.

The arguments io, mmio and mmio_pref represent the start and end
addresses of resource, into which we must fit the current bridge window.

The steps taken by pci_bus_distribute_available_resources():

  - For io, mmio and mmio_pref, increase .start to align with the alignment
    of the current bridge window (otherwise the current bridge window may
    not fit within the available range).

  - For io, mmio and mmio_pref, adjust the current bridge window to the
    size after the above.

  - Count the number of hotplug bridges and normal bridges on this bus.

  - If the total number of bridges is one, give that bridge all of the
    resources and return.

  - If there are no hotplug bridges, return.

  - For io, mmio and mmio_pref, increase .start by the amount required for
    each bridge resource on the bus for non hotplug bridges, giving extra
    room to make up for alignment of those resources.

  - For io, mmio and mmio_pref, calculate the resource size per hotplug
    bridge which is available after the previous steps.

  - For io, mmio and mmio_pref, distribute the resources to each hotplug
    bridge, with the sizes calculated above.

The motivation for fixing this is enabling devices that require greater
than 1MB alignment. This fixes the case where the user hot-adds devices
with BAR alignment >1MB and Linux fails to assign resources to it.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199581
Link: https://lore.kernel.org/r/PSXP216MB0438C2BFD0FD3691ED9C83F4803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 16:57:28 -06:00
Nicholas Johnson 7779385484 PCI: Remove local variable usage in pci_bus_distribute_available_resources()
In pci_bus_distribute_available_resources(), use resource_size() rather
than the local available_io, etc.  No functional change intended; this just
makes the preceding patch smaller.

[bhelgaas: extracted from https://lore.kernel.org/r/PSXP216MB0438587C47CBEDF365B1EA27803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM]
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 16:56:57 -06:00
Nicholas Johnson d555a50fd6 PCI: Pass size + alignment to pci_bus_distribute_available_resources()
Change pci_bus_distribute_available_resources() arguments from
resource_size_t to struct resource to add more information required to get
the alignment correct for bridge windows with alignment >1M.

We require (size, alignment), instead of just (size) which is what is
currently available. The change from resource_size_t to struct resource
does just that.

Note that the struct resource arguments are passed by value and not by
reference. We do not want to pass by reference and change the resource size
of the parent bridge window. We only want the size information.

No functional change intended.

Link: https://lore.kernel.org/r/PSXP216MB0438587C47CBEDF365B1EA27803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM
[bhelgaas: split parts to other patches to reduce the size of this one]
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 16:56:47 -06:00
Nicholas Johnson 053eb5c150 PCI: Rename variables
In pci_bus_distribute_available_resources(), rename:

  io         =>  io_per_hp
  mmio       =>  mmio_per_hp
  mmio_pref  =>  mmio_pref_per_hp

No functional change; this is just to make a subsequent patch smaller.

[bhelgaas: extracted from https://lore.kernel.org/r/PSXP216MB0438587C47CBEDF365B1EA27803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM]
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 16:55:54 -06:00
Nicholas Johnson 3d67a2dbdb PCI: Remove unnecessary braces
Remove unnecessary braces in pci_bus_distribute_available_resources().  No
functional changes.

Link: https://lore.kernel.org/r/PSXP216MB0438061CB4442460BB92A75F803C0@PSXP216MB0438.KORP216.PROD.OUTLOOK.COM
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-01-29 14:15:53 -06:00
Logan Gunthorpe 9db8dc6d07 PCI: Don't disable bridge BARs when assigning bus resources
Some PCI bridges implement BARs in addition to bridge windows.  For
example, here's a PLX switch:

  04:00.0 PCI bridge: PLX Technology, Inc. PEX 8724 24-Lane, 6-Port PCI
            Express Gen 3 (8 GT/s) Switch, 19 x 19mm FCBGA (rev ca)
	    (prog-if 00 [Normal decode])
      Flags: bus master, fast devsel, latency 0, IRQ 30, NUMA node 0
      Memory at 90a00000 (32-bit, non-prefetchable) [size=256K]
      Bus: primary=04, secondary=05, subordinate=0a, sec-latency=0
      I/O behind bridge: 00002000-00003fff
      Memory behind bridge: 90000000-909fffff
      Prefetchable memory behind bridge: 0000380000800000-0000380000bfffff

Previously, when the kernel assigned resource addresses (with the
pci=realloc command line parameter, for example) it could clear the struct
resource corresponding to the BAR.  When this happened, lspci would report
this BAR as "ignored":

   Region 0: Memory at <ignored> (32-bit, non-prefetchable) [size=256K]

This is because the kernel reports a zero start address and zero flags
in the corresponding sysfs resource file and in /proc/bus/pci/devices.
Investigation with 'lspci -x', however, shows the BIOS-assigned address
will still be programmed in the device's BAR registers.

It's clearly a bug that the kernel lost track of the BAR value, but in most
cases, this still won't result in a visible issue because nothing uses the
memory, so nothing is affected.  However, when an IOMMU is in use, it will
not reserve this space in the IOVA because the kernel no longer thinks the
range is valid.  (See dmar_init_reserved_ranges() for the Intel
implementation of this.)

Without the proper reserved range, a DMA mapping may allocate an IOVA that
matches a bridge BAR, which results in DMA accesses going to the BAR
instead of the intended RAM.

The problem was in pci_assign_unassigned_root_bus_resources().  When any
resource from a bridge device fails to get assigned, the code set the
resource's flags to zero.  This makes sense for bridge windows, as they
will be re-enabled later, but for regular BARs, it makes the kernel
permanently lose track of the fact that they decode address space.

Change pci_assign_unassigned_root_bus_resources() and
pci_assign_unassigned_bridge_resources() so they only clear "res->flags"
for bridge *windows*, not bridge BARs.

Fixes: da7822e5ad ("PCI: update bridge resources to get more big ranges when allocating space (again)")
Link: https://lore.kernel.org/r/20200108213208.4612-1-logang@deltatee.com
[bhelgaas: commit log, check for pci_is_bridge()]
Reported-by: Kit Chow <kchow@gigaio.com>
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-01-13 13:23:02 -06:00
Nicholas Johnson c13704f568 PCI: Avoid double hpmemsize MMIO window assignment
Previously, the kernel sometimes assigned more MMIO or MMIO_PREF space than
desired.  For example, if the user requested 128M of space with
"pci=realloc,hpmemsize=128M", we sometimes assigned 256M:

  pci 0000:06:01.0: BAR 14: assigned [mem 0x90100000-0xa00fffff] = 256M
  pci 0000:06:04.0: BAR 14: assigned [mem 0xa0200000-0xb01fffff] = 256M

With this patch applied:

  pci 0000:06:01.0: BAR 14: assigned [mem 0x90100000-0x980fffff] = 128M
  pci 0000:06:04.0: BAR 14: assigned [mem 0x98200000-0xa01fffff] = 128M

This happened when in the first pass, the MMIO_PREF succeeded but the MMIO
failed. In the next pass, because MMIO_PREF was already assigned, the
attempt to assign MMIO_PREF returned an error code instead of success
(nothing more to do, already allocated). Hence, the size which was actually
allocated, but thought to have failed, was placed in the MMIO window.

The bug resulted in the MMIO_PREF being added to the MMIO window, which
meant doubling if MMIO_PREF size = MMIO size. With a large MMIO_PREF, the
MMIO window would likely fail to be assigned altogether due to lack of
32-bit address space.

Change find_free_bus_resource() to do the following:

  - Return first unassigned resource of the correct type.
  - If there is none, return first assigned resource of the correct type.
  - If none of the above, return NULL.

Returning an assigned resource of the correct type allows the caller to
distinguish between already assigned and no resource of the correct type.

Add checks in pbus_size_io() and pbus_size_mem() to return success if
resource returned from find_free_bus_resource() is already allocated.

This avoids pbus_size_io() and pbus_size_mem() returning error code to
__pci_bus_size_bridges() when a resource has been successfully assigned in
a previous pass. This fixes the existing behaviour where space for a
resource could be reserved multiple times in different parent bridge
windows.

Link: https://lore.kernel.org/lkml/20190531171216.20532-2-logang@deltatee.com/T/#u
Link: https://bugzilla.kernel.org/show_bug.cgi?id=203243
Link: https://lore.kernel.org/r/PS2P216MB075563AA6AD242AA666EDC6A80760@PS2P216MB0755.KORP216.PROD.OUTLOOK.COM
Reported-by: Kit Chow <kchow@gigaio.com>
Reported-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2019-11-14 15:02:10 -06:00
Nicholas Johnson d7b8a21752 PCI: Add "pci=hpmmiosize" and "pci=hpmmioprefsize" parameters
The existing "pci=hpmemsize=nn[KMG]" kernel parameter overrides the default
size of both the non-prefetchable and the prefetchable MMIO windows for
hotplug bridges.

Add "pci=hpmmiosize=nn[KMG]" to override the default size of only the
non-prefetchable MMIO window.

Add "pci=hpmmioprefsize=nn[KMG]" to override the default size of only the
prefetchable MMIO window.

Link: https://lore.kernel.org/r/SL2P216MB0187E4D0055791957B7E2660806B0@SL2P216MB0187.KORP216.PROD.OUTLOOK.COM
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2019-10-23 10:27:09 -05:00
Benjamin Herrenschmidt fb794a708a PCI: Protect pci_reassign_bridge_resources() against concurrent addition/removal
pci_reassign_bridge_resources() can be called by pci_resize_resource() at
runtime, it walks the PCI tree up and down, and it isn't currently
protected against any changes or hotplug operation.

Hold the pci_bus_sem to protect it.

Link: https://lore.kernel.org/r/7339fd73ccaf58552737ab10008333fd9f7723f2.camel@kernel.crashing.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-09-30 14:53:31 -05:00
Denis Efremov 39098edbd7 PCI: Use PCI_SRIOV_NUM_BARS in loops instead of PCI_IOV_RESOURCE_END
Writing loop conditions as "i < NUM" is a common C idiom; using "i <= END"
is unusual and thus prone to errors.  Change loops to use the former.

Link: https://lore.kernel.org/r/20190806140715.19847-1-efremov@linux.com
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
2019-08-08 15:12:12 -05:00
Nicholas Johnson 6a381ea694 PCI: Skip resource distribution when no hotplug bridges
If "hotplug_bridges == 0", "!dev->is_hotplug_bridge" is always true, so the
loop that divides the remaining resources among hotplug-capable bridges
does nothing.

Check for "hotplug_bridges == 0" earlier, so we don't even have to compute
the amount of remaining resources.  No functional change intended.

Link: https://lore.kernel.org/r/PS2P216MB0642C7A485649D2D787A1C6F80000@PS2P216MB0642.KORP216.PROD.OUTLOOK.COM
Link: https://lore.kernel.org/r/20190622210310.180905-3-helgaas@kernel.org
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2019-07-02 13:56:54 -05:00
Nicholas Johnson 5c6bcc344b PCI: Simplify pci_bus_distribute_available_resources()
Reorder pci_bus_distribute_available_resources() to group related code
together.  No functional change intended.

Link: https://lore.kernel.org/r/PS2P216MB0642C7A485649D2D787A1C6F80000@PS2P216MB0642.KORP216.PROD.OUTLOOK.COM
Link: https://lore.kernel.org/r/20190622210310.180905-2-helgaas@kernel.org
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2019-07-02 13:56:26 -05:00
Benjamin Herrenschmidt 7ac0d094fb PCI: Don't auto-realloc if we're preserving firmware config
Prevent auto-enabling of bridges reallocation when the FW tells us that the
initial configuration must be preserved for a given host bridge.

Link: https://lore.kernel.org/r/20190615002359.29577-3-benh@kernel.crashing.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-06-21 18:11:53 -05:00
Bjorn Helgaas c7a1c2bbb6 Merge branch 'pci/trivial'
- Cleanup PCI register definitions, typos, etc (Bjorn Helgaas)

  - Remove unnecessary use of user-space types in CPER (Bjorn Helgaas)

  - Cleanup setup-bus.c comments & whitespace (Nicholas Johnson)

* pci/trivial:
  PCI: Cleanup setup-bus.c comments and whitespace
  CPER: Remove unnecessary use of user-space types
  CPER: Add UEFI spec references
  PCI: Fix comment typos
  PCI: Cleanup register definition width and whitespace

# Conflicts:
#	drivers/pci/pci.c
#	drivers/pci/setup-bus.c
2019-05-13 18:34:48 -05:00
Mohan Kumar 34c6b7105e PCI: Replace dev_printk(KERN_DEBUG) with dev_info(), etc
Replace dev_printk(KERN_DEBUG) with dev_info(), etc to be more consistent
with other logging and avoid checkpatch warnings.

The KERN_DEBUG messages could be converted to dev_dbg(), but that depends
on CONFIG_DYNAMIC_DEBUG and DEBUG, and we want most of these messages to
*always* be in the dmesg log.

Link: https://lore.kernel.org/lkml/1555733240-19875-1-git-send-email-mohankumar718@gmail.com
Signed-off-by: Mohan Kumar <mohankumar718@gmail.com>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-05-09 07:49:58 -05:00
Nicholas Johnson 0d6076184a PCI: Cleanup setup-bus.c comments and whitespace
Cleanup comments, kernel-doc, coding style.  No functional changes
intended; comment and whitespace changes only.

Link: https://lore.kernel.org/lkml/PS2P216MB06427E290A68CDB921FB4B2980250@PS2P216MB0642.KORP216.PROD.OUTLOOK.COM
Signed-off-by: Nicholas Johnson <nicholas.johnson-opensource@outlook.com.au>
[bhelgaas: tidy related things throughout the file]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-05-07 15:53:08 -05:00
Honghui Zhang b2fb5cc574 PCI: Rely on config space header type, not class code
The PCI configuration space header type tells us whether the device is a
bridge, a CardBus bridge, or a normal device, and defines the layout of the
rest of the header (PCI r3.0 sec 6.1, PCIe r4.0 sec 7.5.1.1.9).

When we rely on the header format, e.g., when we're dealing with bridge
windows, we should check the header type, not the class code.  The class
code is loosely related to the header type, but is often incorrect and the
spec doesn't actually require it to be related to the header format.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com>
[bhelgaas: changelog, keep the PCI_CLASS_BRIDGE_HOST check]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-01-30 10:57:08 -06:00
Bjorn Helgaas 51c48b3101 PCI: Probe bridge window attributes once at enumeration-time
pci_bridge_check_ranges() determines whether a bridge supports the optional
I/O and prefetchable memory windows and sets the flag bits in the bridge
resources.  This *could* be done once during enumeration except that the
resource allocation code completely clears the flag bits, e.g., in the
pci_assign_unassigned_bridge_resources() path.

The problem with pci_bridge_check_ranges() in the resource allocation path
is that we may allocate resources after devices have been claimed by
drivers, and pci_bridge_check_ranges() *changes* the window registers to
determine whether they're writable.  This may break concurrent accesses to
devices behind the bridge.

Add a new pci_read_bridge_windows() to determine whether a bridge supports
the optional windows, call it once during enumeration, remember the
results, and change pci_bridge_check_ranges() so it doesn't touch the
bridge windows but sets the flag bits based on those remembered results.

Link: https://lore.kernel.org/linux-pci/1506151482-113560-1-git-send-email-wangzhou1@hisilicon.com
Link: https://lists.gnu.org/archive/html/qemu-devel/2018-12/msg02082.html
Reported-by: Yandong Xu <xuyandong2@huawei.com>
Tested-by: Yandong Xu <xuyandong2@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Ofer Hayut <ofer@lightbitslabs.com>
Cc: Roy Shterman <roys@lightbitslabs.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Zhou Wang <wangzhou1@hisilicon.com>
2019-01-22 12:56:35 -06:00
Jon Derrick de3ffa3011 PCI: Equalize hotplug memory and io for occupied and empty slots
Currently, a hotplug bridge will be given hpmemsize additional memory
and hpiosize additional io if available, in order to satisfy any future
hotplug allocation requirements.

These calculations don't consider the current memory/io size of the
hotplug bridge/slot, so hotplug bridges/slots which have downstream
devices will be allocated their current allocation in addition to the
hpmemsize value.

This makes for possibly undesirable results with a mix of unoccupied and
occupied slots (ex, with hpmemsize=2M):

  02:03.0 PCI bridge: <-- Occupied
	  Memory behind bridge: d6200000-d64fffff [size=3M]
  02:04.0 PCI bridge: <-- Unoccupied
	  Memory behind bridge: d6500000-d66fffff [size=2M]

This change considers the current allocation size when using the
hpmemsize/hpiosize parameters to make the reservations predictable for
the mix of unoccupied and occupied slots:

  02:03.0 PCI bridge: <-- Occupied
	  Memory behind bridge: d6200000-d63fffff [size=2M]
  02:04.0 PCI bridge: <-- Unoccupied
	  Memory behind bridge: d6400000-d65fffff [size=2M]

Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-10-02 16:04:40 -05:00
Mika Westerberg 14fe5951b6 PCI: Move resource distribution for single bridge outside loop
If there is only a single bridge on the bus, we assign all resources to it.
Currently this is done as a part of the resource distribution loop but it
does not have to be there, and moving it outside actually improves
readability because we can then save one indent level in the loop.

While there we can add hotplug_bridges == 1 && normal_bridges == 0 to
the same block because they are dealt the same way.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2018-06-04 12:08:06 -05:00
Bjorn Helgaas df62ab5e0f PCI: Tidy comments
Remove pointless comments that tell us the file name, remove blank line
comments, follow multi-line comment conventions.  No functional change
intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-03-19 14:20:43 -05:00
Bjorn Helgaas ab8c609356 Merge branch 'pci/spdx' into next
* pci/spdx:
  PCI: Add SPDX GPL-2.0+ to replace implicit GPL v2 or later statement
  PCI: Add SPDX GPL-2.0+ to replace GPL v2 or later boilerplate
  PCI: Add SPDX GPL-2.0 to replace COPYING boilerplate
  PCI: Add SPDX GPL-2.0 to replace GPL v2 boilerplate
  PCI: Add SPDX GPL-2.0 when no license was specified
2018-02-01 11:40:07 -06:00
Bjorn Helgaas 7328c8f48d PCI: Add SPDX GPL-2.0 when no license was specified
b24413180f ("License cleanup: add SPDX GPL-2.0 license identifier to
files with no license") added SPDX GPL-2.0 to several PCI files that
previously contained no license information.

Add SPDX GPL-2.0 to all other PCI files that did not contain any license
information and hence were under the default GPL version 2 license of the
kernel.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-26 11:45:16 -06:00
Frederick Lawler 7506dc7989 PCI: Add wrappers for dev_printk()
Add PCI-specific dev_printk() wrappers and use them to simplify the code
slightly.  No functional change intended.

Signed-off-by: Frederick Lawler <fred@fredlawl.com>
[bhelgaas: squash into one patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-01-18 12:55:24 -06:00
Markus Elfring c7abb2352c PCI: Remove unnecessary messages for memory allocation failures
Per ebfdc40969 ("checkpatch: attempt to find unnecessary 'out of memory'
messages"), when a memory allocation fails, the memory subsystem emits
generic "out of memory" messages (see slab_out_of_memory() for some of this
logging).  Therefore, additional error messages in the caller don't add
much value.

Remove messages that merely report "out of memory".

This preserves some messages that report additional information, e.g.,
allocation failures that mean we drop hotplug events.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[bhelgaas: changelog, squash patches, make similar changes to acpiphp,
cpqphp, ibmphp, keep warning when dropping hotplug event]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-01-17 08:41:41 -06:00
Bjorn Helgaas 104d1e40cf Merge branch 'pci/resource' into next
* pci/resource:
  PCI: Fail pci_map_rom() if the option ROM is invalid
  PCI: Move pci_map_rom() error path
  x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 00-1f, 30-3f, 60-7f)
  PCI: Add pci_resize_resource() for resizing BARs
  PCI: Add resizable BAR infrastructure
  PCI: Add PCI resource type mask #define
2017-11-14 12:11:25 -06:00
Mika Westerberg 1a5767725c PCI: Distribute available resources to hotplug-capable bridges
The same problem that we have with bus space applies to other resources
as well. Linux only allocates the minimal amount of resources so that
the devices currently present barely fit there. This prevents extending
the chain later on because the resource windows allocated for hotplug
downstream ports are too small.

Follow what we already did for bus number and assign all available extra
resources to hotplug-capable bridges. This makes it possible to extend the
hierarchy later.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-11-06 18:49:00 -06:00
Andy Shevchenko 24a0c654d7 PCI: Add for_each_pci_bridge() helper
The following pattern is often used:

  list_for_each_entry(dev, &bus->devices, bus_list) {
    if (pci_is_bridge(dev)) {
      ...
    }
  }

Add a for_each_pci_bridge() helper to make that code easier to write and
read by reducing indentation level.  It also saves one or few lines of code
in each occurrence.

Convert PCI core parts here at the same time.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[bhelgaas: fold in http://lkml.kernel.org/r/20171013165352.25550-1-andriy.shevchenko@linux.intel.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-11-06 18:48:58 -06:00
Christian König 8bb705e3e7 PCI: Add pci_resize_resource() for resizing BARs
Add a pci_resize_resource() interface to allow device drivers to resize
BARs of their devices.

This is useful for devices with large local storage, e.g., graphics
devices.  These devices often only expose 256MB BARs initially to be
compatible with 32-bit systems.

This function only tries to reprogram the windows of the bridge directly
above the requesting device and only the BAR of the same type (usually mem,
64bit, prefetchable).  This is done to avoid disturbing other drivers by
changing the BARs of their devices.

Drivers should use the following sequence to resize their BARs:
1. Disable memory decoding of the device using the PCI cfg dword.
2. Use pci_release_resource() to release all BARs which can move during the
   resize, including the one you want to resize.
3. Call pci_resize_resource() for each BAR you want to resize.
4. Call pci_assign_unassigned_bus_resources() to reassign new locations
   for all BARs which are not resized, but could move.
5. If everything worked as expected, enable memory decoding in the device
   again using the PCI cfg dword.

Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-10-25 16:07:31 -05:00
Christian König cb21bc9469 PCI: Add PCI resource type mask #define
Add a #define for the PCI resource type mask.  We use this mask multiple
times in the bus setup.

Signed-off-by: Christian König <christian.koenig@amd.com>
[bhelgaas: move to setup-bus.c]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2017-10-24 14:40:13 -05:00