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path: root/drivers/pci/pcie/aspm.c
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2015-06-10PCI/ASPM: Simplify Clock Power Management settingBjorn Helgaas1-8/+5
Update the Link Control Enable Clock Power Management bit the same way we update the ASPM Control bits, with a single call of pcie_capability_clear_and_set_word(). No functional change; this just makes both paths use the same style. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-26PCI/ASPM: Use dev->has_secondary_link to find downstream linksYijing Wang1-6/+10
We allocate pcie_link_state for the component at the upstream end of a Link. Previously we did this by allocating pcie_link_state for Root Ports and Downstream Ports. This works fine for the typical topology: 00:1c.0 Root Port [bridge to bus 02] 02:00.0 Upstream Port [bridge to bus 03] 03:00.0 Downstream Port [bridge to bus 04] 04:00.0 Endpoint or Switch Port However, it is possible to have a Root Port connected to a Downstream Port instead of an Upstream Port, as in Robert White's ATCA system: 00:1c.0 Root Port [bridge to bus 02] 02:00.0 Downstream Port [bridge to bus 03] 03:01.0 Downstream Port [bridge to bus 04] 04:00.0 Endpoint or Switch Port In this topology, we wrongly allocated pcie_link_state for the 02:00.0 Downstream Port, which is actually the *downstream* end of a link. This led to the following NULL pointer dereference when we tried to connect this link into the tree of links starting at the 00:1c.0 Root Port: BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 IP: [<ffffffff81550324>] pcie_aspm_init_link_state+0x744/0x850 Hardware name: Kontron B3001/B3001, BIOS 4.6.3 08/07/2012 Call Trace: [<ffffffff8153b865>] pci_scan_slot+0xd5/0x120 [<ffffffff8153ca1d>] pci_scan_child_bus+0x2d/0xd0 ... Instead of relying on the component type to identify the upstream end of a link, use the "dev->has_secondary_link" field. This means it's now possible for an Upstream Port to have a link on its secondary side, so alloc_pcie_link_state() needs to connect links originating from both Upstream and Downstream Ports into the tree. [bhelgaas: changelog, add comment] Link: https://bugzilla.kernel.org/show_bug.cgi?id=94361 Link: http://lkml.kernel.org/r/54EB81B2.4050904@pobox.com Reported-by: Robert White <rwhite@pobox.com> Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-20PCI/ASPM: Remove redundant PCIe port type checkingYijing Wang1-15/+4
We decide in alloc_pcie_link_state() whether to allocate a pcie_link_state for a device. After that, it's sufficient to check pdev->link_state. We don't need to check the PCIe port type again. Remove the redundant PCIe port type checking. [bhelgaas: changelog] Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-20PCI/ASPM: Drop __pci_disable_link_state() useless "force" parameterBjorn Helgaas1-5/+4
After 387d37577fdd ("PCI: Don't clear ASPM bits when the FADT declares it's unsupported"), the "force" parameter to __pci_disable_link_state() is always "false". Remove the "force" parameter and assume it's always false. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-04-09PCI: Don't clear ASPM bits when the FADT declares it's unsupportedMatthew Garrett1-18/+0
Communications with a hardware vendor confirm that the expected behaviour on systems that set the FADT ASPM disable bit but which still grant full PCIe control is for the OS to leave any BIOS configuration intact and refuse to touch the ASPM bits. This mimics the behaviour of Windows. Signed-off-by: Matthew Garrett <mjg59@coreos.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-01-09PCI/ASPM: Use standard parsing functions for sysfs settersChris J Arges1-5/+7
The functions link_state_store() and clk_ctl_store() had just subtracted ASCII '0' from input which could lead to undesired results. Instead, use Linux string functions to safely parse input. [bhelgaas: check kstrtouint() return value] Signed-off-by: Chris J Arges <chris.j.arges@canonical.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-13PCI: Remove unused pcie_aspm_enabled()Stephen Hemminger1-12/+0
My philosophy is unused code is dead code. And dead code is subject to bit rot and is a likely source of bugs. Use it or lose it. This reverts part of 3e1b16002af2 ("ACPI/PCI: PCIe ASPM _OSC support capabilities called when root bridge added"), removing this interface: pcie_aspm_enabled() [bhelgaas: split to separate patch] Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: Andrew Patterson <andrew.patterson@hp.com>
2013-11-14PCI: Fix whitespace, capitalization, and spelling errorsBjorn Helgaas1-1/+1
Fix whitespace, capitalization, and spelling errors. No functional change. I know "busses" is not an error, but "buses" was more common, so I used it consistently. Signed-off-by: Marta Rybczynska <rybczynska@gmail.com> (pci_reset_bridge_secondary_bus()) Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-28PCI: Fix kerneldoc for pci_disable_link_state()Yijing Wang1-4/+9
Fix kerneldoc for pci_disable_link_state(). [bhelgaas: expand comment, fix typos] Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-05-21PCI/ASPM: Warn when driver asks to disable ASPM, but we can't do itBjorn Helgaas1-3/+13
Some devices have hardware problems related to using ASPM. Drivers for these devices use pci_disable_link_state() to prevent their device from entering L0s or L1. But on platforms where the OS doesn't have permission to manage ASPM, pci_disable_link_state() doesn't actually disable ASPM. Windows has a similar mechanism ("PciASPMOptOut"), and when the OS doesn't have control of ASPM, it doesn't actually disable ASPM either. This patch just adds a warning in dmesg about the fact that pci_disable_link_state() is doing nothing. Reported-by: Emmanuel Grumbach <egrumbach@gmail.com> Reference: https://lkml.kernel.org/r/CANUX_P3F5YhbZX3WGU-j1AGpbXb_T9Bis2ErhvKkFMtDvzatVQ@mail.gmail.com Reference: https://bugzilla.kernel.org/show_bug.cgi?id=57331 Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-02-26Merge tag 'pci-v3.9-changes' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI changes from Bjorn Helgaas: "Host bridge hotplug - Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu) - Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu) - Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu) - Stop caching _PRT and make independent of bus numbers (Yinghai Lu) PCI device hotplug - Clean up cpqphp dead code (Sasha Levin) - Disable ARI unless device and upstream bridge support it (Yijing Wang) - Initialize all hot-added devices (not functions 0-7) (Yijing Wang) Power management - Don't touch ASPM if disabled (Joe Lawrence) - Fix ASPM link state management (Myron Stowe) Miscellaneous - Fix PCI_EXP_FLAGS accessor (Alex Williamson) - Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov) - Document hotplug resource and MPS parameters (Yijing Wang) - Add accessor for PCIe capabilities (Myron Stowe) - Drop pciehp suspend/resume messages (Paul Bolle) - Make pci_slot built-in only (not a module) (Jiang Liu) - Remove unused PCI/ACPI bind ops (Jiang Liu) - Removed used pci_root_bus (Bjorn Helgaas)" * tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (51 commits) PCI/ACPI: Don't cache _PRT, and don't associate them with bus numbers PCI: Fix PCI Express Capability accessors for PCI_EXP_FLAGS ACPI / PCI: Make pci_slot built-in only, not a module PCI/PM: Clear state_saved during suspend PCI: Use atomic_inc_return() rather than atomic_add_return() PCI: Catch attempts to disable already-disabled devices PCI: Disable Bus Master unconditionally in pci_device_shutdown() PCI: acpiphp: Remove dead code for PCI host bridge hotplug PCI: acpiphp: Create companion ACPI devices before creating PCI devices PCI: Remove unused "rc" in virtfn_add_bus() PCI: pciehp: Drop suspend/resume ENTRY messages PCI/ASPM: Don't touch ASPM if forcibly disabled PCI/ASPM: Deallocate upstream link state even if device is not PCIe PCI: Document MPS parameters pci=pcie_bus_safe, pci=pcie_bus_perf, etc PCI: Document hpiosize= and hpmemsize= resource reservation parameters PCI: Use PCI Express Capability accessor PCI: Introduce accessor to retrieve PCIe Capabilities Register PCI: Put pci_dev in device tree as early as possible PCI: Skip attaching driver in device_add() PCI: acpiphp: Keep driver loaded even if no slots found ...
2013-02-02PCI/ASPM: Don't touch ASPM if forcibly disabledJoe Lawrence1-0/+3
Don't allocate and track PCIe ASPM state when "pcie_aspm=off" is specified on the kernel command line. Based-on-patch-from: Matthew Garrett <mjg59@srcf.ucam.org> Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: David Bulkow <david.bulkow@stratus.com> Acked-by: Myron Stowe <myron.stowe@redhat.com>
2013-02-02PCI/ASPM: Deallocate upstream link state even if device is not PCIeMyron Stowe1-4/+1
On PCI bus hotplug removal, pcie_aspm_exit_link_state() can potentially skip parent devices that have link_state allocated. Instead of exiting early if a given device is not PCIe, check whether or not the device's parent has link_state allocated. This enables pcie_aspm_exit_link_state() to properly clean up parent link_state when the last function in a slot might not be PCIe. Reported-by: Joe Lawrence <joe.lawrence@stratus.com> Tested-by: Joe Lawrence <joe.lawrence@stratus.com> Signed-off-by: Myron Stowe <myron.stowe@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-01-15PCI: Allow pcie_aspm=force even when FADT indicates it is unsupportedColin Ian King1-0/+3
Right now using pcie_aspm=force will not enable ASPM if the FADT indicates ASPM is unsupported. However, the semantics of force should probably allow for this, especially as they did before 3c076351c4 ("PCI: Rework ASPM disable code") This patch just skips the clearing of any ASPM setup that the firmware has carried out on this bus if pcie_aspm=force is being used. Reference: http://bugs.launchpad.net/bugs/962038 Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org
2012-12-07Merge branch 'pci/bjorn-pcie-cap' into nextBjorn Helgaas1-5/+6
* pci/bjorn-pcie-cap: ath9k: Use standard #defines for PCIe Capability ASPM fields iwlwifi: Use standard #defines for PCIe Capability ASPM fields iwlwifi: collapse wrapper for pcie_capability_read_word() iwlegacy: Use standard #defines for PCIe Capability ASPM fields iwlegacy: collapse wrapper for pcie_capability_read_word() cxgb3: Use standard #defines for PCIe Capability ASPM fields PCI: Add standard PCIe Capability Link ASPM field names PCI/portdrv: Use PCI Express Capability accessors PCI: Use standard PCIe Capability Link register field names PCI: Add and use standard PCI-X Capability register names
2012-12-07PCI: Add standard PCIe Capability Link ASPM field namesBjorn Helgaas1-5/+6
Add standard #defines for ASPM fields in PCI Express Link Capability and Link Control registers. Previously we used PCIE_LINK_STATE_L0S and PCIE_LINK_STATE_L1 directly, but these are defined for the Linux ASPM interfaces, e.g., pci_disable_link_state(), and only coincidentally match the actual register bits. PCIE_LINK_STATE_CLKPM, also part of that interface, does not match the register bit. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
2012-11-08PCI: Convert dev_printk(KERN_<LEVEL> to dev_<level>(Joe Perches1-5/+2
dev_<level> calls take less code than dev_printk(KERN_<LEVEL> and reducing object size is good. Coalesce formats for easier grep. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-08-23PCI/ASPM: Use PCI Express Capability accessorsJiang Liu1-51/+26
Use PCI Express Capability access functions to simplify PCIe ASPM. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-08-23PCI: Introduce pci_pcie_type(dev) to replace pci_dev->pcie_typeYijing Wang1-21/+21
Introduce an inline function pci_pcie_type(dev) to extract PCIe device type from pci_dev->pcie_flags_reg field, and prepare for removing pci_dev->pcie_type. Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2012-03-31ASPM: Fix pcie devices with non-pcie childrenMatthew Garrett1-3/+10
Since 3.2.12 and 3.3, some systems are failing to boot with a BUG_ON. Some other systems using the pata_jmicron driver fail to boot because no disks are detected. Passing pcie_aspm=force on the kernel command line works around it. The cause: commit 4949be16822e ("PCI: ignore pre-1.1 ASPM quirking when ASPM is disabled") changed the behaviour of pcie_aspm_sanity_check() to always return 0 if aspm is disabled, in order to avoid cases where we changed ASPM state on pre-PCIe 1.1 devices. This skipped the secondary function of pcie_aspm_sanity_check which was to avoid us enabling ASPM on devices that had non-PCIe children, causing trouble later on. Move the aspm_disabled check so we continue to honour that scenario. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=42979 and http://bugs.debian.org/665420 Reported-by: Romain Francoise <romain@orebokech.com> # kernel panic Reported-by: Chris Holland <bandidoirlandes@gmail.com> # disk detection trouble Signed-off-by: Matthew Garrett <mjg@redhat.com> Cc: stable@vger.kernel.org Tested-by: Hatem Masmoudi <hatem.masmoudi@gmail.com> # Dell Latitude E5520 Tested-by: janek <jan0x6c@gmail.com> # pata_jmicron with JMB362/JMB363 [jn: with more symptoms in log message] Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24Merge branch 'linux-next' of ↵Linus Torvalds1-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci Pull PCI changes (including maintainer change) from Jesse Barnes: "This pull has some good cleanups from Bjorn and Yinghai, as well as some more code from Yinghai to better handle resource re-allocation when enabled. There's also a new initcall_debug feature from Arjan which will print out quirk timing information to help identify slow quirks for fixing or refinement (Yinghai sent in a few patches to do just that once the new debug code landed). Beyond that, I'm handing off PCI maintainership to Bjorn Helgaas. He's been a core PCI and Linux contributor for some time now, and has kindly volunteered to take over. I just don't feel I have the time for PCI review and work that it deserves lately (I've taken on some other projects), and haven't been as responsive lately as I'd like, so I approached Bjorn asking if he'd like to manage things. He's going to give it a try, and I'm confident he'll do at least as well as I have in keeping the tree managed, patches flowing, and keeping things stable." Fix up some fairly trivial conflicts due to other cleanups (mips device resource fixup cleanups clashing with list handling cleanup, ppc iseries removal clashing with pci_probe_only cleanup etc) * 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci: (112 commits) PCI: Bjorn gets PCI hotplug too PCI: hand PCI maintenance over to Bjorn Helgaas unicore32/PCI: move <asm-generic/pci-bridge.h> include to asm/pci.h sparc/PCI: convert devtree and arch-probed bus addresses to resource powerpc/PCI: allow reallocation on PA Semi powerpc/PCI: convert devtree bus addresses to resource powerpc/PCI: compute I/O space bus-to-resource offset consistently arm/PCI: don't export pci_flags PCI: fix bridge I/O window bus-to-resource conversion x86/PCI: add spinlock held check to 'pcibios_fwaddrmap_lookup()' PCI / PCIe: Introduce command line option to disable ARI PCI: make acpihp use __pci_remove_bus_device instead PCI: export __pci_remove_bus_device PCI: Rename pci_remove_behind_bridge to pci_stop_and_remove_behind_bridge PCI: Rename pci_remove_bus_device to pci_stop_and_remove_bus_device PCI: print out PCI device info along with duration PCI: Move "pci reassigndev resource alignment" out of quirks.c PCI: Use class for quirk for usb host controller fixup PCI: Use class for quirk for ti816x class fixup PCI: Use class for quirk for intel e100 interrupt fixup ...
2012-03-08PCI: ignore pre-1.1 ASPM quirking when ASPM is disabledMatthew Garrett1-0/+3
Right now we won't touch ASPM state if ASPM is disabled, except in the case where we find a device that appears to be too old to reliably support ASPM. Right now we'll clear it in that case, which is almost certainly the wrong thing to do. The easiest way around this is just to disable the blacklisting when ASPM is disabled. Signed-off-by: Matthew Garrett <mjg@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2012-02-17PCI: pcie: Add support for setting default ASPM policyMatthew Garrett1-0/+8
Distributions may wish to provide different defaults for PCIE ASPM depending on their target audience. Provide a configuration option for choosing the default policy. Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-12-05PCI: Rework ASPM disable codeMatthew Garrett1-21/+37
Right now we forcibly clear ASPM state on all devices if the BIOS indicates that the feature isn't supported. Based on the Microsoft presentation "PCI Express In Depth for Windows Vista and Beyond", I'm starting to think that this may be an error. The implication is that unless the platform grants full control via _OSC, Windows will not touch any PCIe features - including ASPM. In that case clearing ASPM state would be an error unless the platform has granted us that control. This patch reworks the ASPM disabling code such that the actual clearing of state is triggered by a successful handoff of PCIe control to the OS. The general ASPM code undergoes some changes in order to ensure that the ability to clear the bits isn't overridden by ASPM having already been disabled. Further, this theoretically now allows for situations where only a subset of PCIe roots hand over control, leaving the others in the BIOS state. It's difficult to know for sure that this is the right thing to do - there's zero public documentation on the interaction between all of these components. But enough vendors enable ASPM on platforms and then set this bit that it seems likely that they're expecting the OS to leave them alone. Measured to save around 5W on an idle Thinkpad X220. Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-06-29PCIe ASPM: forcedly -> forciblyMichael Witten1-1/+1
Merriam-Webster tells us that the word exists. However ... * Google suggests `forcibly' because it doesn't recognize `forcedly'. * Google lists 494 thousand results for `forcedly'. * Google lists 13.7 million results for `forcibly'. * Linus's repo contains 1 occurrence of `forcedly' ( 0 after my change). * Linus's repo contains 60 occurrences of `forcibly' (61 after my change). Signed-off-by: Michael Witten <mfwitten@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-05-21PCI/e1000e: Add and use pci_disable_link_state_locked()Yinghai Lu1-3/+16
Need to use it in _e1000e_disable_aspm. This routine is used for error recovery, where the pci_bus_sem is already held, and we don't want pci_disable_link_state to try to take it again. So add a locked variant for use in cases like this. Found lock up: [ 2374.654557] kworker/32:1 D ffff881027f6b0f0 0 6075 2 0x00000000 [ 2374.654816] ffff88503f099a68 0000000000000046 ffff88503f098000 0000000000004000 [ 2374.654837] 00000000001d1ec0 ffff88503f099fd8 00000000001d1ec0 ffff88503f099fd8 [ 2374.654860] 0000000000004000 00000000001d1ec0 ffff88503dcc8000 ffff88503f090000 [ 2374.654880] Call Trace: [ 2374.654898] [<ffffffff810b1302>] ? __lock_acquired+0x3a/0x224 [ 2374.654914] [<ffffffff81c2b59c>] ? _raw_spin_unlock_irq+0x30/0x36 [ 2374.654925] [<ffffffff810b069d>] ? trace_hardirqs_on_caller+0x1f/0x178 [ 2374.654936] [<ffffffff81c2ab24>] rwsem_down_failed_common+0xd3/0x103 [ 2374.654945] [<ffffffff810b158f>] ? __lock_contended+0x3a/0x2a2 [ 2374.654955] [<ffffffff81c2ab7b>] rwsem_down_read_failed+0x12/0x14 [ 2374.654967] [<ffffffff813371e4>] call_rwsem_down_read_failed+0x14/0x30 [ 2374.654981] [<ffffffff8135df20>] ? pci_disable_link_state+0x5f/0xf5 [ 2374.654990] [<ffffffff81c2a0e6>] ? down_read+0x7e/0x91 [ 2374.654999] [<ffffffff8135df20>] ? pci_disable_link_state+0x5f/0xf5 [ 2374.655008] [<ffffffff8135df20>] pci_disable_link_state+0x5f/0xf5 [ 2374.655024] [<ffffffff81661796>] e1000e_disable_aspm+0x55/0x5a [ 2374.655037] [<ffffffff816677eb>] e1000_io_slot_reset+0x59/0xea [ 2374.655048] [<ffffffff8135fe0d>] ? report_mmio_enabled+0x5d/0x5d [ 2374.655057] [<ffffffff8135fe3b>] report_slot_reset+0x2e/0x5d [ 2374.655072] [<ffffffff8135369e>] pci_walk_bus+0x8a/0xb7 [ 2374.655081] [<ffffffff8135fe0d>] ? report_mmio_enabled+0x5d/0x5d [ 2374.655091] [<ffffffff813603be>] broadcast_error_message+0xa4/0xb2 [ 2374.655101] [<ffffffff81352c71>] ? pci_bus_read_config_dword+0x72/0x80 [ 2374.655110] [<ffffffff813606df>] do_recovery+0x9e/0xf9 [ 2374.655120] [<ffffffff81360786>] handle_error_source+0x4c/0x51 [ 2374.655129] [<ffffffff81360974>] aer_isr_one_error+0x1e9/0x21a [ 2374.655138] [<ffffffff81360a6c>] aer_isr+0xc7/0xcc [ 2374.655147] [<ffffffff813609a5>] ? aer_isr_one_error+0x21a/0x21a [ 2374.655159] [<ffffffff81096d9f>] process_one_work+0x237/0x3ec [ 2374.655168] [<ffffffff81096d10>] ? process_one_work+0x1a8/0x3ec [ 2374.655178] [<ffffffff8109728d>] worker_thread+0x17c/0x240 [ 2374.655186] [<ffffffff810b0803>] ? trace_hardirqs_on+0xd/0xf [ 2374.655196] [<ffffffff81097111>] ? manage_workers+0xab/0xab [ 2374.655209] [<ffffffff8109c8ed>] kthread+0xa0/0xa8 [ 2374.655223] [<ffffffff81c332d4>] kernel_thread_helper+0x4/0x10 [ 2374.655232] [<ffffffff81c2b880>] ? retint_restore_args+0xe/0xe [ 2374.655243] [<ffffffff8109c84d>] ? __init_kthread_worker+0x5b/0x5b [ 2374.655252] [<ffffffff81c332d0>] ? gs_change+0xb/0xb when aer happens, pci_walk_bus already have down_read(&pci_bus_sem)... then report_slot_reset ==> e1000_io_slot_reset ==> e1000e_disable_aspm ==> pci_disable_link_state... We can not use pci_disable_link_state, and it will try to hold pci_bus_sem again. Try to have __pci_disable_link_state that will not need to hold pci_bus_sem. -v2: change name to pci_disable_link_state_locked() according to Jesse. [jbarnes: make sure new function is exported for modules] Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-05-11PCI: Enable ASPM state clearing regardless of policyAlex Williamson1-1/+1
Commit 2f671e2d allowed us to clear ASPM state when the FADT tells us it isn't supported, but we don't put this into effect if the aspm_policy is set to POLICY_POWERSAVE. Enable the state to be cleared regardless of policy. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-03-21PCI: Changing ASPM policy, via /sys, to POWERSAVE could cause NMIsNaga Chumbalkar1-0/+4
v3 -> v2: Modified the text that describes the problem v2 -> v1: Returned -EPERM v1 : http://marc.info/?l=linux-pci&m=130013194803727&w=2 For servers whose hardware cannot handle ASPM the BIOS ought to set the FADT bit shown below: In Sec 5.2.9.3 (IA-PC Boot Arch. Flags) of ACPI4.0a Specification, please see Table 5-11: PCIe ASPM Controls: If set, indicates to OSPM that it must not enable OPSM ASPM control on this platform. However there are shipping servers whose BIOS did not set this bit. (An example is the HP ProLiant DL385 G6. A Maintenance BIOS will fix that). For such servers even if a call is made via pci_no_aspm(), based on _OSC support in the BIOS, it may be too late because the ASPM code may have already allocated and filled its "link_list". So if a user sets the ASPM "policy" to "powersave" via /sys then pcie_aspm_set_policy() will run through the "link_list" and re-configure ASPM policy on devices that advertise ASPM L0s/L1 capability: # echo powersave > /sys/module/pcie_aspm/parameters/policy # cat /sys/module/pcie_aspm/parameters/policy default performance [powersave] That can cause NMIs since the hardware doesn't play well with ASPM: [ 1651.906015] NMI: PCI system error (SERR) for reason b1 on CPU 0. [ 1651.906015] Dazed and confused, but trying to continue Ideally, the BIOS should have set that FADT bit in the first place but we could be more robust - especially given the fact that Windows doesn't cause NMIs in the above scenario. There should be a sanity check to not allow a user to modify ASPM policy when aspm_disabled is set. Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-03-21PCI: PCIe links may not get configured for ASPM under POWERSAVE modeNaga Chumbalkar1-0/+22
v3 -> v2: Moved ASPM enabling logic to pci_set_power_state() v2 -> v1: Preserved the logic in pci_raw_set_power_state() : Added ASPM enabling logic after scanning Root Bridge : http://marc.info/?l=linux-pci&m=130046996216391&w=2 v1 : http://marc.info/?l=linux-pci&m=130013164703283&w=2 The assumption made in commit 41cd766b065970ff6f6c89dd1cf55fa706c84a3d (PCI: Don't enable aspm before drivers have had a chance to veto it) that pci_enable_device() will result in re-configuring ASPM when aspm_policy is POWERSAVE is no longer valid. This is due to commit 97c145f7c87453cec90e91238fba5fe2c1561b32 (PCI: read current power state at enable time) which resets dev->current_state to D0. Due to this the call to pcie_aspm_pm_state_change() is never made. Note the equality check (below) that returns early: ./drivers/pci/pci.c: pci_raw_set_pci_power_state() 546 /* Check if we're already there */ 547 if (dev->current_state == state) 548 return 0; Therefore OSPM never configures the PCIe links for ASPM to turn them "on". Fix it by configuring ASPM from the pci_enable_device() code path. This also allows a driver such as the e1000e networking driver a chance to disable ASPM (L0s, L1), if need be, prior to enabling the device. A driver may perform this action if the device is known to mis-behave wrt ASPM. Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-03-21PCI/ACPI: Report ASPM support to BIOS if not disabled from command lineRafael J. Wysocki1-0/+7
We need to distinguish the situation in which ASPM support is disabled from the command line or through .config from the situation in which it is disabled, because the hardware or BIOS can't handle it. In the former case we should not report ASPM support to the BIOS through ACPI _OSC, but in the latter case we should do that. Introduce pcie_aspm_support_enabled() that can be used by acpi_pci_root_add() to determine whether or not it should report ASPM support to the BIOS through _OSC. Cc: stable@kernel.org References: https://bugzilla.kernel.org/show_bug.cgi?id=29722 References: https://bugzilla.kernel.org/show_bug.cgi?id=20232 Reported-and-tested-by: Ortwin Glück <odi@odi.ch> Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-12-23PCI: Disable ASPM if BIOS asks us toMatthew Garrett1-4/+17
We currently refuse to touch the ASPM registers if the BIOS tells us that ASPM isn't supported. This can cause problems if the BIOS has (for any reason) enabled ASPM on some devices anyway. Change the code such that we explicitly clear ASPM if the FADT indicates that ASPM isn't supported, and make sure we tidy up appropriately on device removal in order to deal with the hotplug case. If ASPM is disabled because the BIOS doesn't hand over control then we won't touch the registers. Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-07-30PCI: Don't enable aspm before drivers have had a chance to veto itMatthew Garrett1-2/+14
The aspm code will currently set the configured aspm policy before drivers have had an opportunity to indicate that their hardware doesn't support it. Unfortunately, putting some hardware in L0 or L1 can result in the hardware no longer responding to any requests, even after aspm is disabled. It makes more sense to leave aspm policy at the BIOS defaults at initial setup time, reconfiguring it after pci_enable_device() is called. This allows the driver to blacklist individual devices beforehand. Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Matthew Garrett <mjg@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-12-17PCI: change PCI nomenclature in drivers/pci/ (comment changes)Stefan Assmann1-2/+2
Changing occurrences of variants of PCI-X and PCIe to the PCI-SIG terms listed in the "Trademark and Logo Usage Guidelines". http://www.pcisig.com/developers/procedures/logos/Trademark_and_Logo_Usage_Guidelines_updated_112206.pdf Patch is limited to drivers/pci/ and changes concern comments only. Signed-off-by: Stefan Assmann <sassmann@redhat.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-12-05PCI: fix BUG_ON triggered by logical PCIe root port removalKenji Kaneshige1-2/+4
This problem happened when removing PCIe root port using PCI logical hotplug operation. The immediate cause of this problem is that the pointer to invalid data structure is passed to pcie_update_aspm_capable() by pcie_aspm_exit_link_state(). When pcie_aspm_exit_link_state() received a pointer to root port link, it unconfigures the root port link and frees its data structure at first. At this point, there are not links to configure under the root port and the data structure for root port link is already freed. So pcie_aspm_exit_link_state() must not call pcie_update_aspm_capable() and pcie_config_aspm_path(). This patch fixes the problem by changing pcie_aspm_exit_link_state() not to call pcie_update_aspm_capable() and pcie_config_aspm_path() if the specified link is root port link. ------------[ cut here ]------------ kernel BUG at drivers/pci/pcie/aspm.c:606! invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC last sysfs file: /sys/devices/pci0000:40/0000:40:13.0/remove CPU 1 Modules linked in: shpchp Pid: 9345, comm: sysfsd Not tainted 2.6.32-rc5 #98 ProLiant DL785 G6 RIP: 0010:[<ffffffff811df69b>] [<ffffffff811df69b>] pcie_update_aspm_capable+0x15/0xbe RSP: 0018:ffff88082a2f5ca0 EFLAGS: 00010202 RAX: 0000000000000e77 RBX: ffff88182cc3e000 RCX: ffff88082a33d006 RDX: 0000000000000001 RSI: ffffffff811dff4a RDI: ffff88182cc3e000 RBP: ffff88082a2f5cc0 R08: ffff88182cc3e000 R09: 0000000000000000 R10: ffff88182fc00180 R11: ffff88182fc00198 R12: ffff88182cc3e000 R13: 0000000000000000 R14: ffff88182cc3e000 R15: ffff88082a2f5e20 FS: 00007f259a64b6f0(0000) GS:ffff880864600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b CR2: 00007feb53f73da0 CR3: 000000102cc94000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process sysfsd (pid: 9345, threadinfo ffff88082a2f4000, task ffff88082a33cf00) Stack: ffff88182cc3e000 ffff88182cc3e000 0000000000000000 ffff88082a33cf00 <0> ffff88082a2f5cf0 ffffffff811dff52 ffff88082a2f5cf0 ffff88082c525168 <0> ffff88402c9fd2f8 ffff88402c9fd2f8 ffff88082a2f5d20 ffffffff811d7db2 Call Trace: [<ffffffff811dff52>] pcie_aspm_exit_link_state+0xf5/0x11e [<ffffffff811d7db2>] pci_stop_bus_device+0x76/0x7e [<ffffffff811d7d67>] pci_stop_bus_device+0x2b/0x7e [<ffffffff811d7e4f>] pci_remove_bus_device+0x15/0xb9 [<ffffffff811dcb8c>] remove_callback+0x29/0x3a [<ffffffff81135aeb>] sysfs_schedule_callback_work+0x15/0x6d [<ffffffff81072790>] worker_thread+0x19d/0x298 [<ffffffff8107273b>] ? worker_thread+0x148/0x298 [<ffffffff81135ad6>] ? sysfs_schedule_callback_work+0x0/0x6d [<ffffffff810765c0>] ? autoremove_wake_function+0x0/0x38 [<ffffffff810725f3>] ? worker_thread+0x0/0x298 [<ffffffff8107629e>] kthread+0x7d/0x85 [<ffffffff8102eafa>] child_rip+0xa/0x20 [<ffffffff8102e4bc>] ? restore_args+0x0/0x30 [<ffffffff81076221>] ? kthread+0x0/0x85 [<ffffffff8102eaf0>] ? child_rip+0x0/0x20 Code: 89 e5 8a 50 48 31 c0 c0 ea 03 83 e2 07 e8 b2 de fe ff c9 48 98 c3 55 48 89 e5 41 56 49 89 fe 41 55 41 54 53 48 83 7f 10 00 74 04 <0f> 0b eb fe 48 8b 05 da 7d 63 00 4c 8d 60 e8 4c 89 e1 eb 24 4c RIP [<ffffffff811df69b>] pcie_update_aspm_capable+0x15/0xbe RSP <ffff88082a2f5ca0> ---[ end trace 6ae0f65bdeab8555 ]--- Reported-by: Alex Chiang <achiang@hp.com> Tested-by: Alex Chiang <achiang@hp.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-25PCIe ASPM: use pci_is_pcie()Kenji Kaneshige1-9/+12
Change for PCIe ASPM driver to use pci_is_pcie() instead of checking pci_dev->is_pcie. Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-25PCIe ASPM: use pci_pcie_cap()Kenji Kaneshige1-10/+10
Use pci_pcie_cap() instead of pci_find_capability() to get PCIe capability offset in PCIe ASPM driver. This avoids unnecessary search in PCI configuration space. Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-17PCI ASPM: support L1 onlyKenji Kaneshige1-3/+0
The definition of the ASPM support field in the Link Capabilities Register had been changed by the "ASPM optionality ECN" as follows: <Before> 00b Reserved 01b L0s Supported 10b Reserved 11b L0s and L1 Supported <After> 00b No ASPM Support 01b L0s Supported 10b L1 Supported 11b L0s and L1 Supported Current linux ASPM driver doesn't enable ASPM if the support field is 00b or 10b. So there is no impact about 00b. But current linux ASPM driver doesn't enable L1 if the support field is 10b. With this patch, 10b (L1 support) is handled properly. Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-10PCI ASPM: support per direction l0s managementKenji Kaneshige1-63/+107
The L0s state can be managed separately for each direction (upstream direction and downstream direction) of the link. But in the current implementation, those are mixed up. With this patch, L0s for each direction are managed separately. To maintain three states (upstream direction L0s, downstream L0s and L1), 'aspm_support', 'aspm_enabled', 'aspm_capable', 'aspm_disable' and 'aspm_default' fields in struct pcie_link_state are changed to 3-bit from 2-bit. The 'latency' field is separated to two 'latency_up' and 'latency_dw' fields to maintain exit latencies for each direction of the link. For L0, 'latency_up.l0' and 'latency_dw.l0' are used to configure upstream direction L0s and downstream direction L0s respectively. For L1, larger value of 'latency_up.l1' and 'latency_dw.l1' is considered as L1 exit latency. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-10PCI ASPM: support partial aspm enablementKenji Kaneshige1-164/+47
In the current implementation, ASPM L0s/L1 is disabled for all links in the hierarchy if one of the link doesn't meet latency requirement. But we can partially enable ASPM L0s/L1 on sub-tree in the hierarchy. This patch allows partial L0s/L1 enablement in the hierarchy. And it also reduce the calculation cost of ASPM configuration very much. In the previous implementation, all links were enabled with the same state. With this patch, enabled state for each link is determined simply as follows (the 'requested' is from policy_to_aspm_state()). enabled = requested & (link->aspm_capable & link->aspm_disable) Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-10PCI ASPM: introduce capable flagKenji Kaneshige1-31/+86
Introduce 'aspm_capable' field to maintain the capable ASPM setting of the link. By the 'aspm_capable', we don't need to recheck latency every time ASPM policy is changed. Each bit in 'aspm_capable' is associated to ASPM state (L0S/L1). The bit is set if the associated ASPM state is supported by the link and it satisfies the latency requirement (i.e. exit latency < endpoint acceptable latency). The 'aspm_capable' is updated when - an endpoint device is added (boot time or hot-plug time) - an endpoint device is removed (hot-unplug time) - PCI power state is changed. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-10PCI ASPM: introduce disable flagKenji Kaneshige1-17/+24
Introduce 'aspm_disable' flag to manage disabled ASPM state more robust way. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-10PCI ASPM: fix possible null pointer dereferenceKenji Kaneshige1-8/+9
Fix possible NULL dereference in pcie_aspm_exit_link_state(). This patch also cleanup some code. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-10PCI ASPM: remove redundant list checkKenji Kaneshige1-3/+0
Remove the following check in __pcie_aspm_config_link() because it nerver be true. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-10PCI ASPM: do not clear enabled field by support fieldKenji Kaneshige1-3/+3
We must not clear bits in 'aspm_enabled' using 'aspm_support', or 'aspm_enabled' and 'aspm_default' might be different from the actual state. In addtion, 'aspm_default' should be intialized even if 'aspm_support' is 0. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-19PCI ASPM: remove get_root_port_linkKenji Kaneshige1-13/+11
By having a pointer to the root port link, we can remove loops in get_root_port_link() to search the root port link. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-19PCI ASPM: cleanup pcie_aspm_sanity_checkKenji Kaneshige1-12/+9
Minor cleanup for pcie_aspm_sanity_check(). Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-19PCI ASPM: remove has_switch fieldKenji Kaneshige1-4/+1
We don't need the 'has_switch' field in the struct pcie_link_state. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-19PCI ASPM: cleanup calc_Lx_latencyKenji Kaneshige1-39/+34
Cleanup for calc_L0S_latency() and calc_L1_latency(). - Separate exit latency and acceptable latency calculation. - Some minor cleanups. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-19PCI ASPM: cleanup pcie_aspm_get_cap_deviceKenji Kaneshige1-5/+4
Minor cleanup for pcie_aspm_get_cap_device(). Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-19PCI ASPM: cleanup clkpm checksKenji Kaneshige1-14/+20
In the current ASPM implementation, callers of pcie_set_clock_pm() check Clock PM capability of the link or current Clock PM state of the link. This check should be done in pcie_set_clock_pm() itself. This patch moves those checks into pcie_set_clock_pm(). It also introduces pcie_set_clkpm_nocheck() that is equivalent to old pcie_set_clock_pm(), for the caller who wants to change Clocl PM state regardless of the Clock PM capability or current Clock PM state. In addition, this patch changes the function name from pcie_set_clock_pm() to pcie_set_clkpm() for consistency. Acked-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-25 05:31:03 +0300