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* PCI: Relax bridge window tail sizing rulesIlpo Järvinen2024-06-121-2/+77
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During remove & rescan cycle, PCI subsystem will recalculate and adjust the bridge window sizing that was initially done by "BIOS". The size calculation is based on the required alignment of the largest resource among the downstream resources as per pbus_size_mem() (unimportant or zero parameters marked with "..."): min_align = calculate_mem_align(aligns, max_order); size0 = calculate_memsize(size, ..., min_align); inside calculate_memsize(), for the largest alignment: min_align = align1 >> 1; ... return min_align; and then in calculate_memsize(): return ALIGN(max(size, ...), align); If the original bridge window sizing tried to conserve space, this will lead to massive increase of the required bridge window size when the downstream has a large disparity in BAR sizes. E.g., with 16MiB and 16GiB BARs this results in 24GiB bridge window size even if 16MiB BAR does not require gigabytes of space to fit. When doing remove & rescan for a bus that contains such a PCI device, a larger bridge window is suddenly required on rescan but when there is a bridge window upstream that is already assigned based on the original size, it cannot be enlarged to the new requirement. This causes the allocation of the bridge window to fail (0x600000000 > 0x400ffffff): pci 0000:02:01.0: PCI bridge to [bus 03] pci 0000:02:01.0: bridge window [mem 0x40400000-0x405fffff] pci 0000:02:01.0: bridge window [mem 0x6000000000-0x6400ffffff 64bit pref] pci 0000:01:00.0: PCI bridge to [bus 02-04] pci 0000:01:00.0: bridge window [mem 0x40400000-0x406fffff] pci 0000:01:00.0: bridge window [mem 0x6000000000-0x6400ffffff 64bit pref] pci 0000:03:00.0: device released pci 0000:02:01.0: device released pcieport 0000:01:00.0: scanning [bus 02-04] behind bridge, pass 0 pci 0000:02:01.0: PCI bridge to [bus 03] pci 0000:02:01.0: bridge window [mem 0x40400000-0x405fffff] pci 0000:02:01.0: bridge window [mem 0x6000000000-0x6400ffffff 64bit pref] pci 0000:02:01.0: scanning [bus 03-03] behind bridge, pass 0 pci 0000:03:00.0: BAR 0 [mem 0x6400000000-0x6400ffffff 64bit pref] pci 0000:03:00.0: BAR 2 [mem 0x6000000000-0x63ffffffff 64bit pref] pci 0000:03:00.0: ROM [mem 0x40400000-0x405fffff pref] pci 0000:02:01.0: PCI bridge to [bus 03] pci 0000:02:01.0: scanning [bus 03-03] behind bridge, pass 1 pcieport 0000:01:00.0: scanning [bus 02-04] behind bridge, pass 1 pci 0000:02:01.0: bridge window [mem size 0x600000000 64bit pref]: can't assign; no space pci 0000:02:01.0: bridge window [mem size 0x600000000 64bit pref]: failed to assign pci 0000:02:01.0: bridge window [mem 0x40400000-0x405fffff]: assigned pci 0000:03:00.0: BAR 2 [mem size 0x400000000 64bit pref]: can't assign; no space pci 0000:03:00.0: BAR 2 [mem size 0x400000000 64bit pref]: failed to assign pci 0000:03:00.0: BAR 0 [mem size 0x01000000 64bit pref]: can't assign; no space pci 0000:03:00.0: BAR 0 [mem size 0x01000000 64bit pref]: failed to assign pci 0000:03:00.0: ROM [mem 0x40400000-0x405fffff pref]: assigned pci 0000:02:01.0: PCI bridge to [bus 03] pci 0000:02:01.0: bridge window [mem 0x40400000-0x405fffff] This is a major surprise for users who are suddenly left with a device that was working fine with the original bridge window sizing. Even if the already assigned bridge window could be enlarged by reallocation in some cases (something the current code does not attempt to do), it is not possible in general case and the large amount of wasted space at the tail of the bridge window may lead to other resource exhaustion problems on Root Complex level (think of multiple PCIe cards with VFs and BAR size disparity in a single system). PCI BARs only need natural alignment (PCIe r6.1, sec 7.5.1.2.1) and bridge memory windows need 1MiB (sec 7.5.1.3). The current bridge window tail alignment rule was introduced in the commit 5d0a8965aea9 ("[PATCH] 2.5.14: New PCI allocation code (alpha, arm, parisc) [2/2]") that only states: "pbus_size_mem: core stuff; tested with randomly generated sets of resources". It does not explain the motivation for the extra tail space allocated that is not truly needed by the downstream resources. As such, it is far from clear if it ever has been required by any HW. To prevent devices with BAR size disparity from becoming unusable after remove & rescan cycle, attempt to do a truly minimal allocation for memory resources if needed. First check if the normally calculated bridge window will not fit into an already assigned upstream resource. In such case, try with relaxed bridge window tail sizing rules instead where no extra tail space is requested beyond what the downstream resources require. Only enforce the alignment requirement of the bridge window itself (normally 1MiB). With this patch, the resources are successfully allocated: pci 0000:02:01.0: PCI bridge to [bus 03] pci 0000:02:01.0: scanning [bus 03-03] behind bridge, pass 1 pcieport 0000:01:00.0: scanning [bus 02-04] behind bridge, pass 1 pcieport 0000:01:00.0: Assigned bridge window [mem 0x6000000000-0x6400ffffff 64bit pref] to [bus 02-04] cannot fit 0x600000000 required for 0000:02:01.0 bridging to [bus 03] pci 0000:02:01.0: bridge window [mem 0x6000000000-0x6400ffffff 64bit pref] to [bus 03] requires relaxed alignment rules pcieport 0000:01:00.0: Assigned bridge window [mem 0x40400000-0x406fffff] to [bus 02-04] free space at [mem 0x40400000-0x405fffff] pci 0000:02:01.0: bridge window [mem 0x6000000000-0x6400ffffff 64bit pref]: assigned pci 0000:02:01.0: bridge window [mem 0x40400000-0x405fffff]: assigned pci 0000:03:00.0: BAR 2 [mem 0x6000000000-0x63ffffffff 64bit pref]: assigned pci 0000:03:00.0: BAR 0 [mem 0x6400000000-0x6400ffffff 64bit pref]: assigned pci 0000:03:00.0: ROM [mem 0x40400000-0x405fffff pref]: assigned pci 0000:02:01.0: PCI bridge to [bus 03] pci 0000:02:01.0: bridge window [mem 0x40400000-0x405fffff] pci 0000:02:01.0: bridge window [mem 0x6000000000-0x6400ffffff 64bit pref] This patch draws inspiration from the initial investigations and work by Mika Westerberg. Closes: https://bugzilla.kernel.org/show_bug.cgi?id=216795 Link: https://lore.kernel.org/linux-pci/20190812144144.2646-1-mika.westerberg@linux.intel.com/ Fixes: 5d0a8965aea9 ("[PATCH] 2.5.14: New PCI allocation code (alpha, arm, parisc) [2/2]") Link: https://lore.kernel.org/r/20240507102523.57320-9-ilpo.jarvinen@linux.intel.com Tested-by: Lidong Wang <lidong.wang@intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
* PCI: Make minimum bridge window alignment reference more obviousIlpo Järvinen2024-06-121-2/+4
| | | | | | | | | | | | Calculations related to bridge window size contain literal 20 that is the minimum alignment for a bridge window. Make the code more obvious by converting the literal 20 to __ffs(SZ_1M). Link: https://lore.kernel.org/r/20240507102523.57320-8-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> [bhelgaas: squash https://lore.kernel.org/r/20240612093250.17544-1-ilpo.jarvinen@linux.intel.com] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
* PCI: Fix resource double counting on remove & rescanIlpo Järvinen2024-05-281-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pbus_size_mem() keeps the size of the optional resources in children_add_size. When calculating the PCI bridge window size, calculate_memsize() lower bounds size by old_size before adding children_add_size and performing the window size alignment. This results in double counting for the resources in children_add_size because old_size may be based on the previous size of the bridge window after it has already included children_add_size (that is, size1 in pbus_size_mem() from an earlier invocation of that function). As a result, on repeated remove of the bus & rescan cycles the resource size keeps increasing when children_add_size is non-zero as can be seen from this extract: iomem0: 23fffd00000-23fffdfffff : PCI Bus 0000:03 # 1MiB iomem1: 20000000000-200001fffff : PCI Bus 0000:03 # 2MiB iomem2: 20000000000-200002fffff : PCI Bus 0000:03 # 3MiB iomem3: 20000000000-200003fffff : PCI Bus 0000:03 # 4MiB iomem4: 20000000000-200004fffff : PCI Bus 0000:03 # 5MiB Solve the double counting by moving old_size check later in calculate_memsize() so that children_add_size is already accounted for. After the patch, the bridge window retains its size as expected: iomem0: 23fffd00000-23fffdfffff : PCI Bus 0000:03 # 1MiB iomem1: 20000000000-200000fffff : PCI Bus 0000:03 # 1MiB iomem2: 20000000000-200000fffff : PCI Bus 0000:03 # 1MiB Fixes: a4ac9fea016f ("PCI : Calculate right add_size") Link: https://lore.kernel.org/r/20240507102523.57320-2-ilpo.jarvinen@linux.intel.com Tested-by: Lidong Wang <lidong.wang@intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
* PCI: Use resource names in PCI log messagesPuranjay Mohan2023-12-161-10/+20
| | | | | | | | | | | Use the pci_resource_name() to get the name of the resource and use it while printing log messages. [bhelgaas: rename to match struct resource * names, also use names in other BAR messages] Link: https://lore.kernel.org/r/20211106112606.192563-3-puranjay12@gmail.com Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
* PCI: Make pci_assign_unassigned_resources() non-initRandy Dunlap2023-10-051-1/+1
| | | | | | | | | | | | | | | | | | Fix a section mismatch warning on Sparc 32-bit: WARNING: modpost: vmlinux: section mismatch in reference: leon_pci_init+0xf8 (section: .text) -> pci_assign_unassigned_resources (section: .init.text) This is due to this comment from arch/sparc/kernel/leon_pci.c: The LEON architecture does not rely on a BIOS or bootloader to setup PCI for us. The Linux generic routines are used to setup resources, reset values of configuration-space register settings are preserved. Link: https://lore.kernel.org/r/20230925042316.15415-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: sparclinux@vger.kernel.org
* PCI: Fix typos in docs and commentsBjorn Helgaas2023-08-251-1/+1
| | | | | | | | | Fix typos in docs and comments. Link: https://lore.kernel.org/r/20230824193712.542167-11-helgaas@kernel.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
* PCI: Make pci_bus_for_each_resource() index optionalAndy Shevchenko2023-04-051-6/+4
| | | | | | | | | | | | | | Refactor pci_bus_for_each_resource() in the same way as pci_dev_for_each_resource(). This allows the index to be hidden inside the implementation so the caller can omit it when it's not used otherwise. No functional changes intended. Link: https://lore.kernel.org/r/20230330162434.35055-6-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Krzysztof Wilczyński <kw@linux.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
* PCI: Introduce pci_dev_for_each_resource()Mika Westerberg2023-04-041-17/+10
| | | | | | | | | | | | | | | | | Instead of open-coding it everywhere introduce a tiny helper that can be used to iterate over each resource of a PCI device, and convert the most obvious users into it. While at it drop doubled empty line before pdev_sort_resources(). No functional changes intended. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230330162434.35055-4-andriy.shevchenko@linux.intel.com Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
* PCI: Distribute available resources for root buses, tooMika Westerberg2023-02-071-1/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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. A previous commit to do this was reverted due to a regression reported by Jonathan Cameron: e96e27fc6f79 ("PCI: Distribute available resources for root buses, too") 5632e2beaf9d ("Revert "PCI: Distribute available resources for root buses, too"") This commit changes pci_bridge_resources_not_assigned() to work with bridges that do not have all the resource windows programmed by the boot firmware (previously we expected all I/O, memory and prefetchable memory were programmed). Link: https://bugzilla.kernel.org/show_bug.cgi?id=216000 Link: https://lore.kernel.org/r/20220905080232.36087-5-mika.westerberg@linux.intel.com Link: https://lore.kernel.org/r/20230131092405.29121-4-mika.westerberg@linux.intel.com Reported-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>
* PCI: Take other bus devices into account when distributing resourcesMika Westerberg2023-02-071-70/+106
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A PCI bridge may reside on a bus with other devices as well. The resource distribution code does not take this into account and therefore it expands the bridge resource windows too much, not leaving space for the other devices (or functions of a multifunction device). This leads to an issue that Jonathan reported when running QEMU with the following topology (QEMU parameters): -device pcie-root-port,port=0,id=root_port13,chassis=0,slot=2 \ -device x3130-upstream,id=sw1,bus=root_port13,multifunction=on \ -device e1000,bus=root_port13,addr=0.1 \ -device xio3130-downstream,id=fun1,bus=sw1,chassis=0,slot=3 \ -device e1000,bus=fun1 The first e1000 NIC here is another function in the switch upstream port. This leads to following errors: 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] Fix this by taking into account bridge windows, device BARs and SR-IOV PF BARs on the bus (PF BARs include space for VF BARS so only account PF BARs), including the ones belonging to bridges themselves if it has any. Link: https://lore.kernel.org/linux-pci/20221014124553.0000696f@huawei.com/ Link: https://lore.kernel.org/linux-pci/6053736d-1923-41e7-def9-7585ce1772d9@ixsystems.com/ Link: https://lore.kernel.org/r/20230131092405.29121-3-mika.westerberg@linux.intel.com Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reported-by: Alexander Motin <mav@ixsystems.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
* PCI: Align extra resources for hotplug bridges properlyMika Westerberg2023-02-071-6/+19
| | | | | | | | | | After division the extra resource space per hotplug bridge may not be aligned according to the window alignment, so align it before passing it down for further distribution. Link: https://lore.kernel.org/r/20230131092405.29121-2-mika.westerberg@linux.intel.com Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
* Revert "PCI: Distribute available resources for root buses, too"Bjorn Helgaas2022-10-141-61/+1
| | | | | | | | | | | | | | | | | This reverts commit e96e27fc6f7971380283768e9a734af16b1716ee. 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>
* PCI: Fix whitespace and indentationMika Westerberg2022-09-211-1/+1
| | | | | | | | | | | | | 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>
* PCI: Distribute available resources for root buses, tooMika Westerberg2022-09-211-1/+61
| | | | | | | | | | | | | | | | | | | 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>
* PCI: Move pci_assign_unassigned_root_bus_resources()Mika Westerberg2022-09-211-113/+113
| | | | | | | | | | | | | 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>
* Merge branch 'pci/misc'Bjorn Helgaas2022-03-221-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - 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
| * PCI: Remove unused assignmentsBjorn Helgaas2022-03-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | PCI: Support BAR sizes up to 8TBDongdong Liu2022-03-031-1/+1
|/ | | | | | | | | | | | | | 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>
* PCI: Prefer 'unsigned int' over bare 'unsigned'Krzysztof Wilczyński2021-10-271-1/+1
| | | | | | | | | | | | | | | | 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 a1ce18e4f941 ("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>
* treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva2020-08-241-1/+1
| | | | | | | | | | 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>
* Merge branch 'pci/doc'Bjorn Helgaas2020-08-061-0/+1
|\ | | | | | | | | | | | | - Fix several kerneldoc warnings (Krzysztof Kozlowski) * pci/doc: PCI: Fix kerneldoc warnings
| * PCI: Fix kerneldoc warningsKrzysztof Kozlowski2020-08-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | PCI: Fix error in panic messageLiao Pingfang2020-07-091-1/+1
|/ | | | | | | | | | | 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>
* Merge branch 'remotes/lorenzo/pci/host-generic'Bjorn Helgaas2020-06-041-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - 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
| * PCI: host-generic: Support building as modulesRob Herring2020-05-011-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* | PCI: Use bridge window names (PCI_BRIDGE_IO_WINDOW etc)Krzysztof Wilczynski2020-05-211-53/+61
|/ | | | | | | | | 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>
* PCI: Add support for root bus sizingIvan Kokshaysky2020-03-301-12/+22
| | | | | | | | | | | | | | | | | | | | | 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>
* PCI: Allow adjust_bridge_window() to shrink resource if necessaryNicholas Johnson2020-01-291-4/+12
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* PCI: Set resource size directly in adjust_bridge_window()Nicholas Johnson2020-01-291-16/+7
| | | | | | | | | | | | | | | | | | | | 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>
* PCI: Rename extend_bridge_window() to adjust_bridge_window()Nicholas Johnson2020-01-291-4/+4
| | | | | | | | | | | 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>
* PCI: Rename extend_bridge_window() parameterNicholas Johnson2020-01-291-4/+4
| | | | | | | | | | | 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>
* PCI: Consider alignment of hot-added bridges when assigning resourcesNicholas Johnson2020-01-291-32/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* PCI: Remove local variable usage in pci_bus_distribute_available_resources()Nicholas Johnson2020-01-291-10/+6
| | | | | | | | | | | 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>
* PCI: Pass size + alignment to pci_bus_distribute_available_resources()Nicholas Johnson2020-01-291-16/+19
| | | | | | | | | | | | | | | | | | | | | | 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>
* PCI: Rename variablesNicholas Johnson2020-01-291-13/+17
| | | | | | | | | | | | | | | 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>
* PCI: Remove unnecessary bracesNicholas Johnson2020-01-291-2/+1
| | | | | | | | | | 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>
* PCI: Don't disable bridge BARs when assigning bus resourcesLogan Gunthorpe2020-01-131-4/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: da7822e5ad71 ("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>
* PCI: Avoid double hpmemsize MMIO window assignmentNicholas Johnson2019-11-141-11/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* PCI: Add "pci=hpmmiosize" and "pci=hpmmioprefsize" parametersNicholas Johnson2019-10-231-11/+13
| | | | | | | | | | | | | | | | | 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>
* PCI: Protect pci_reassign_bridge_resources() against concurrent addition/removalBenjamin Herrenschmidt2019-09-301-1/+7
| | | | | | | | | | | | 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>
* PCI: Use PCI_SRIOV_NUM_BARS in loops instead of PCI_IOV_RESOURCE_ENDDenis Efremov2019-08-081-2/+2
| | | | | | | | | | 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>
* PCI: Skip resource distribution when no hotplug bridgesNicholas Johnson2019-07-021-2/+3
| | | | | | | | | | | | | | | | 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>
* PCI: Simplify pci_bus_distribute_available_resources()Nicholas Johnson2019-07-021-25/+25
| | | | | | | | | | | | 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>
* PCI: Don't auto-realloc if we're preserving firmware configBenjamin Herrenschmidt2019-06-221-0/+5
| | | | | | | | | 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>
* Merge branch 'pci/trivial'Bjorn Helgaas2019-05-141-247/+249
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - 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
| * PCI: Cleanup setup-bus.c comments and whitespaceNicholas Johnson2019-05-071-247/+249
| | | | | | | | | | | | | | | | | | | | 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>
* | PCI: Replace dev_printk(KERN_DEBUG) with dev_info(), etcMohan Kumar2019-05-091-16/+14
|/ | | | | | | | | | | | | | 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>
* PCI: Rely on config space header type, not class codeHonghui Zhang2019-01-301-9/+9
| | | | | | | | | | | | | | | 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>
* PCI: Probe bridge window attributes once at enumeration-timeBjorn Helgaas2019-01-221-41/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* PCI: Equalize hotplug memory and io for occupied and empty slotsJon Derrick2018-10-021-13/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>