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path: root/drivers/pci/pci.c
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2024-09-12PCI: Add missing bridge lock to pci_bus_lock()Dan Williams
[ Upstream commit a4e772898f8bf2e7e1cf661a12c60a5612c4afab ] One of the true positives that the cfg_access_lock lockdep effort identified is this sequence: WARNING: CPU: 14 PID: 1 at drivers/pci/pci.c:4886 pci_bridge_secondary_bus_reset+0x5d/0x70 RIP: 0010:pci_bridge_secondary_bus_reset+0x5d/0x70 Call Trace: <TASK> ? __warn+0x8c/0x190 ? pci_bridge_secondary_bus_reset+0x5d/0x70 ? report_bug+0x1f8/0x200 ? handle_bug+0x3c/0x70 ? exc_invalid_op+0x18/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? pci_bridge_secondary_bus_reset+0x5d/0x70 pci_reset_bus+0x1d8/0x270 vmd_probe+0x778/0xa10 pci_device_probe+0x95/0x120 Where pci_reset_bus() users are triggering unlocked secondary bus resets. Ironically pci_bus_reset(), several calls down from pci_reset_bus(), uses pci_bus_lock() before issuing the reset which locks everything *but* the bridge itself. For the same motivation as adding: bridge = pci_upstream_bridge(dev); if (bridge) pci_dev_lock(bridge); to pci_reset_function() for the "bus" and "cxl_bus" reset cases, add pci_dev_lock() for @bus->self to pci_bus_lock(). Link: https://lore.kernel.org/r/171711747501.1628941.15217746952476635316.stgit@dwillia2-xfh.jf.intel.com Reported-by: Imre Deak <imre.deak@intel.com> Closes: http://lore.kernel.org/r/6657833b3b5ae_14984b29437@dwillia2-xfh.jf.intel.com.notmuch Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Keith Busch <kbusch@kernel.org> [bhelgaas: squash in recursive locking deadlock fix from Keith Busch: https://lore.kernel.org/r/20240711193650.701834-1-kbusch@meta.com] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Hans de Goede <hdegoede@redhat.com> Tested-by: Kalle Valo <kvalo@kernel.org> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-03PCI/DPC: Fix use-after-free on concurrent DPC and hot-removalLukas Wunner
commit 11a1f4bc47362700fcbde717292158873fb847ed upstream. Keith reports a use-after-free when a DPC event occurs concurrently to hot-removal of the same portion of the hierarchy: The dpc_handler() awaits readiness of the secondary bus below the Downstream Port where the DPC event occurred. To do so, it polls the config space of the first child device on the secondary bus. If that child device is concurrently removed, accesses to its struct pci_dev cause the kernel to oops. That's because pci_bridge_wait_for_secondary_bus() neglects to hold a reference on the child device. Before v6.3, the function was only called on resume from system sleep or on runtime resume. Holding a reference wasn't necessary back then because the pciehp IRQ thread could never run concurrently. (On resume from system sleep, IRQs are not enabled until after the resume_noirq phase. And runtime resume is always awaited before a PCI device is removed.) However starting with v6.3, pci_bridge_wait_for_secondary_bus() is also called on a DPC event. Commit 53b54ad074de ("PCI/DPC: Await readiness of secondary bus after reset"), which introduced that, failed to appreciate that pci_bridge_wait_for_secondary_bus() now needs to hold a reference on the child device because dpc_handler() and pciehp may indeed run concurrently. The commit was backported to v5.10+ stable kernels, so that's the oldest one affected. Add the missing reference acquisition. Abridged stack trace: BUG: unable to handle page fault for address: 00000000091400c0 CPU: 15 PID: 2464 Comm: irq/53-pcie-dpc 6.9.0 RIP: pci_bus_read_config_dword+0x17/0x50 pci_dev_wait() pci_bridge_wait_for_secondary_bus() dpc_reset_link() pcie_do_recovery() dpc_handler() Fixes: 53b54ad074de ("PCI/DPC: Await readiness of secondary bus after reset") Closes: https://lore.kernel.org/r/20240612181625.3604512-3-kbusch@meta.com/ Link: https://lore.kernel.org/linux-pci/8e4bcd4116fd94f592f2bf2749f168099c480ddf.1718707743.git.lukas@wunner.de Reported-by: Keith Busch <kbusch@kernel.org> Tested-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-27PCI: Do not wait for disconnected devices when resumingIlpo Järvinen
[ Upstream commit 6613443ffc49d03e27f0404978f685c4eac43fba ] On runtime resume, pci_dev_wait() is called: pci_pm_runtime_resume() pci_pm_bridge_power_up_actions() pci_bridge_wait_for_secondary_bus() pci_dev_wait() While a device is runtime suspended along with its PCI hierarchy, the device could get disconnected. In such case, the link will not come up no matter how long pci_dev_wait() waits for it. Besides the above mentioned case, there could be other ways to get the device disconnected while pci_dev_wait() is waiting for the link to come up. Make pci_dev_wait() exit if the device is already disconnected to avoid unnecessary delay. The use cases of pci_dev_wait() boil down to two: 1. Waiting for the device after reset 2. pci_bridge_wait_for_secondary_bus() The callers in both cases seem to benefit from propagating the disconnection as error even if device disconnection would be more analoguous to the case where there is no device in the first place which return 0 from pci_dev_wait(). In the case 2, it results in unnecessary marking of the devices disconnected again but that is just harmless extra work. Also make sure compiler does not become too clever with dev->error_state and use READ_ONCE() to force a fetch for the up-to-date value. Link: https://lore.kernel.org/r/20240208132322.4811-1-ilpo.jarvinen@linux.intel.com Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27PCI/PM: Avoid D3cold for HP Pavilion 17 PC/1972 PCIe PortsMario Limonciello
[ Upstream commit 256df20c590bf0e4d63ac69330cf23faddac3e08 ] Hewlett-Packard HP Pavilion 17 Notebook PC/1972 is an Intel Ivy Bridge system with a muxless AMD Radeon dGPU. Attempting to use the dGPU fails with the following sequence: ACPI Error: Aborting method \AMD3._ON due to previous error (AE_AML_LOOP_TIMEOUT) (20230628/psparse-529) radeon 0000:01:00.0: not ready 1023ms after resume; waiting radeon 0000:01:00.0: not ready 2047ms after resume; waiting radeon 0000:01:00.0: not ready 4095ms after resume; waiting radeon 0000:01:00.0: not ready 8191ms after resume; waiting radeon 0000:01:00.0: not ready 16383ms after resume; waiting radeon 0000:01:00.0: not ready 32767ms after resume; waiting radeon 0000:01:00.0: not ready 65535ms after resume; giving up radeon 0000:01:00.0: Unable to change power state from D3cold to D0, device inaccessible The issue is that the Root Port the dGPU is connected to can't handle the transition from D3cold to D0 so the dGPU can't properly exit runtime PM. The existing logic in pci_bridge_d3_possible() checks for systems that are newer than 2015 to decide that D3 is safe. This would nominally work for an Ivy Bridge system (which was discontinued in 2015), but this system appears to have continued to receive BIOS updates until 2017 and so this existing logic doesn't appropriately capture it. Add the system to bridge_d3_blacklist to prevent D3cold from being used. Link: https://lore.kernel.org/r/20240307163709.323-1-mario.limonciello@amd.com Reported-by: Eric Heintzmann <heintzmann.eric@free.fr> Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3229 Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Eric Heintzmann <heintzmann.eric@free.fr> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12PCI: Wait for Link Training==0 before starting Link retrainIlpo Järvinen
[ Upstream commit 73cb3a35f94db723c0211ad099bce55b2155e3f0 ] Two changes were made in link retraining logic independent of each other. The commit e7e39756363a ("PCI/ASPM: Avoid link retraining race") added a check to pcie_retrain_link() to ensure no Link Training is currently active to address the Implementation Note in PCIe r6.1 sec 7.5.3.7. At that time pcie_wait_for_retrain() only checked for the Link Training (LT) bit being cleared. The commit 680e9c47a229 ("PCI: Add support for polling DLLLA to pcie_retrain_link()") generalized pcie_wait_for_retrain() into pcie_wait_for_link_status() which can wait either for LT or the Data Link Layer Link Active (DLLLA) bit with 'use_lt' argument and supporting waiting for either cleared or set using 'active' argument. In the merge commit 1abb47390350 ("Merge branch 'pci/enumeration'"), those two divergent branches converged. The merge changed LT bit checking added in the commit e7e39756363a ("PCI/ASPM: Avoid link retraining race") to now wait for completion of any ongoing Link Training using DLLLA bit being set if 'use_lt' is false. When 'use_lt' is false, the pseudo-code steps of what occurs in pcie_retrain_link(): 1. Wait for DLLLA==1 2. Trigger link to retrain 3. Wait for DLLLA==1 Step 3 waits for the link to come up from the retraining triggered by Step 2. As Step 1 is supposed to wait for any ongoing retraining to end, using DLLLA also for it does not make sense because link training being active is still indicated using LT bit, not with DLLLA. Correct the pcie_wait_for_link_status() parameters in Step 1 to only wait for LT==0 to ensure there is no ongoing Link Training. This only impacts the Target Speed quirk, which is the only case where waiting for DLLLA bit is used. It currently works in the problematic case by means of link training getting initiated by hardware repeatedly and respecting the new link parameters set by the caller, which then make training succeed and bring the link up, setting DLLLA and causing pcie_wait_for_link_status() to return success. We are not supposed to rely on luck and need to make sure that LT transitioned through the inactive state though before we initiate link training by hand via RL (Retrain Link) bit. Fixes: 1abb47390350 ("Merge branch 'pci/enumeration'") Link: https://lore.kernel.org/r/20240423130820.43824-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-27PCI/ASPM: Fix deadlock when enabling ASPMJohan Hovold
commit 1e560864159d002b453da42bd2c13a1805515a20 upstream. A last minute revert in 6.7-final introduced a potential deadlock when enabling ASPM during probe of Qualcomm PCIe controllers as reported by lockdep: ============================================ WARNING: possible recursive locking detected 6.7.0 #40 Not tainted -------------------------------------------- kworker/u16:5/90 is trying to acquire lock: ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pcie_aspm_pm_state_change+0x58/0xdc but task is already holding lock: ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pci_walk_bus+0x34/0xbc other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(pci_bus_sem); lock(pci_bus_sem); *** DEADLOCK *** Call trace: print_deadlock_bug+0x25c/0x348 __lock_acquire+0x10a4/0x2064 lock_acquire+0x1e8/0x318 down_read+0x60/0x184 pcie_aspm_pm_state_change+0x58/0xdc pci_set_full_power_state+0xa8/0x114 pci_set_power_state+0xc4/0x120 qcom_pcie_enable_aspm+0x1c/0x3c [pcie_qcom] pci_walk_bus+0x64/0xbc qcom_pcie_host_post_init_2_7_0+0x28/0x34 [pcie_qcom] The deadlock can easily be reproduced on machines like the Lenovo ThinkPad X13s by adding a delay to increase the race window during asynchronous probe where another thread can take a write lock. Add a new pci_set_power_state_locked() and associated helper functions that can be called with the PCI bus semaphore held to avoid taking the read lock twice. Link: https://lore.kernel.org/r/ZZu0qx2cmn7IwTyQ@hovoldconsulting.com Link: https://lore.kernel.org/r/20240130100243.11011-1-johan+linaro@kernel.org Fixes: f93e71aea6c6 ("Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()"") Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: <stable@vger.kernel.org> # 6.7 [bhelgaas: backported to v6.6.y, which contains 8cc22ba3f77c ("Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()""), a backport of f93e71aea6c6. This omits the drivers/pci/controller/dwc/pcie-qcom.c hunk that updates qcom_pcie_enable_aspm(), which was added by 9f4f3dfad8cf ("PCI: qcom: Enable ASPM for platforms supporting 1.9.0 ops"), which is not present in v6.6.28.] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23PCI: Fix active state requirement in PME pollingAlex Williamson
[ Upstream commit 41044d5360685e78a869d40a168491a70cdb7e73 ] The commit noted in fixes added a bogus requirement that runtime PM managed devices need to be in the RPM_ACTIVE state for PME polling. In fact, only devices in low power states should be polled. However there's still a requirement that the device config space must be accessible, which has implications for both the current state of the polled device and the parent bridge, when present. It's not sufficient to assume the bridge remains in D0 and cases have been observed where the bridge passes the D0 test, but the PM state indicates RPM_SUSPENDING and config space of the polled device becomes inaccessible during pci_pme_wakeup(). Therefore, since the bridge is already effectively required to be in the RPM_ACTIVE state, formalize this in the code and elevate the PM usage count to maintain the state while polling the subordinate device. This resolves a regression reported in the bugzilla below where a Thunderbolt/USB4 hierarchy fails to scan for an attached NVMe endpoint downstream of a bridge in a D3hot power state. Link: https://lore.kernel.org/r/20240123185548.1040096-1-alex.williamson@redhat.com Fixes: d3fcd7360338 ("PCI: Fix runtime PM race with PME polling") Reported-by: Sanath S <sanath.s@amd.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218360 Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Sanath S <sanath.s@amd.com> Reviewed-by: Rafael J. Wysocki <rafael@kernel.org> Cc: Lukas Wunner <lukas@wunner.de> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()"Bjorn Helgaas
commit f93e71aea6c60ebff8adbd8941e678302d377869 upstream. This reverts commit 08d0cc5f34265d1a1e3031f319f594bd1970976c. Michael reported that when attempting to resume from suspend to RAM on ASUS mini PC PN51-BB757MDE1 (DMI model: MINIPC PN51-E1), 08d0cc5f3426 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()") caused a 12-second delay with no output, followed by a reboot. Workarounds include: - Reverting 08d0cc5f3426 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()") - Booting with "pcie_aspm=off" - Booting with "pcie_aspm.policy=performance" - "echo 0 | sudo tee /sys/bus/pci/devices/0000:03:00.0/link/l1_aspm" before suspending - Connecting a USB flash drive Link: https://lore.kernel.org/r/20240102232550.1751655-1-helgaas@kernel.org Fixes: 08d0cc5f3426 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()") Reported-by: Michael Schaller <michael@5challer.de> Link: https://lore.kernel.org/r/76c61361-b8b4-435f-a9f1-32b716763d62@5challer.de Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28PCI: Use FIELD_GET() in Sapphire RX 5600 XT Pulse quirkBjorn Helgaas
[ Upstream commit 04e82fa5951ca66495d7b05665eff673aa3852b4 ] Use FIELD_GET() to remove dependences on the field position, i.e., the shift value. No functional change intended. Separate because this isn't as trivial as the other FIELD_GET() changes. See 907830b0fc9e ("PCI: Add a REBAR size quirk for Sapphire RX 5600 XT Pulse") Link: https://lore.kernel.org/r/20231010204436.1000644-3-helgaas@kernel.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Cc: Nirmoy Das <nirmoy.das@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28PCI: Use FIELD_GET() to extract Link WidthIlpo Järvinen
[ Upstream commit d1f9b39da4a5347150246871325190018cda8cb3 ] Use FIELD_GET() to extract PCIe Negotiated and Maximum Link Width fields instead of custom masking and shifting. Link: https://lore.kernel.org/r/20230919125648.1920-7-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> [bhelgaas: drop duplicate include of <linux/bitfield.h>] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28PCI: Do error check on own line to split long "if" conditionsIlpo Järvinen
[ Upstream commit d15f18053e5cc5576af9e7eef0b2a91169b6326d ] Placing PCI error code check inside "if" condition usually results in need to split lines. Combined with additional conditions the "if" condition becomes messy. Convert to the usual error handling pattern with an additional variable to improve code readability. In addition, reverse the logic in pci_find_vsec_capability() to get rid of &&. No functional changes intended. Link: https://lore.kernel.org/r/20230911125354.25501-5-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> [bhelgaas: PCI_POSSIBLE_ERROR()] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-29Merge branch 'pci/misc'Bjorn Helgaas
- Reorder struct pci_dev to avoid holes and reduce size (Christophe JAILLET) - Change pdev->rom_attr_enabled to single bit since it's only a boolean value (Christophe JAILLET) - Use struct_size() in pirq_convert_irt_table() instead of hand-writing it (Christophe JAILLET) - Explicitly include correct DT includes to untangle headers (Rob Herring) - Fix a DOE race between destroy_work_on_stack() and the stack-allocated task->work struct going out of scope in pci_doe() (Ira Weiny) - Use pci_dev_id() when possible instead of manually composing ID from dev->bus->number and dev->devfn (Xiongfeng Wang, Zheng Zengkai) - Move pci_create_resource_files() declarations to linux/pci.h for alpha build warnings (Arnd Bergmann) - Remove unused hotplug function declarations (Yue Haibing) - Remove unused mvebu struct mvebu_pcie.busn (Pali Rohár) - Unexport pcie_port_bus_type (Bjorn Helgaas) - Remove unnecessary sysfs ID local variable initialization (Bjorn Helgaas) - Fix BAR value printk formatting to accommodate 32-bit values (Bjorn Helgaas) - Use consistent pointer types for config access syscall get_user() and put_user() uses (Bjorn Helgaas) - Simplify AER_RECOVER_RING_SIZE definition (Bjorn Helgaas) - Simplify pci_pio_to_address() (Bjorn Helgaas) - Simplify pci_dev_driver() (Bjorn Helgaas) - Fix pci_bus_resetable(), pci_slot_resetable() name typos (Bjorn Helgaas) - Fix code and doc typos and code formatting (Bjorn Helgaas) - Tidy config space save/restore messages (Bjorn Helgaas) * pci/misc: PCI: Tidy config space save/restore messages PCI: Fix code formatting inconsistencies PCI: Fix typos in docs and comments PCI: Fix pci_bus_resetable(), pci_slot_resetable() name typos PCI: Simplify pci_dev_driver() PCI: Simplify pci_pio_to_address() PCI/AER: Simplify AER_RECOVER_RING_SIZE definition PCI: Use consistent put_user() pointer types PCI: Fix printk field formatting PCI: Remove unnecessary initializations PCI: Unexport pcie_port_bus_type PCI: mvebu: Remove unused busn member PCI: Remove unused function declarations PCI/sysfs: Move declarations to linux/pci.h PCI/P2PDMA: Use pci_dev_id() to simplify the code PCI/IOV: Use pci_dev_id() to simplify the code PCI/AER: Use pci_dev_id() to simplify the code PCI: apple: Use pci_dev_id() to simplify the code PCI/DOE: Fix destroy_work_on_stack() race PCI: Explicitly include correct DT includes x86/PCI: Use struct_size() in pirq_convert_irt_table() PCI: Change pdev->rom_attr_enabled to single bit PCI: Reorder pci_dev fields to reduce holes
2023-08-29Merge branch 'pci/vpd'Bjorn Helgaas
- Ensure device is accessible before VPD access via sysfs (Alex Williamson) - Ensure device doesn't go to a low-power state while we're polling for PME (Alex Williamson) * pci/vpd: PCI: Fix runtime PM race with PME polling PCI/VPD: Add runtime power management to sysfs interface
2023-08-29Merge branch 'pci/pm'Bjorn Helgaas
- Only read PCI_PM_CTRL register when available, to avoid reading the wrong register and corrupting dev->current_state (Feiyang Chen) * pci/pm: PCI/PM: Only read PCI_PM_CTRL register when available
2023-08-25PCI/PM: Only read PCI_PM_CTRL register when availableFeiyang Chen
For a device with no Power Management Capability, pci_power_up() previously returned 0 (success) if the platform was able to put the device in D0, which led to pci_set_full_power_state() trying to read PCI_PM_CTRL, even though it doesn't exist. Since dev->pm_cap == 0 in this case, pci_set_full_power_state() actually read the wrong register, interpreted it as PCI_PM_CTRL, and corrupted dev->current_state. This led to messages like this in some cases: pci 0000:01:00.0: Refused to change power state from D3hot to D0 To prevent this, make pci_power_up() always return a negative failure code if the device lacks a Power Management Capability, even if non-PCI platform power management has been able to put the device in D0. The failure will prevent pci_set_full_power_state() from trying to access PCI_PM_CTRL. Fixes: e200904b275c ("PCI/PM: Split pci_power_up()") Link: https://lore.kernel.org/r/20230824013738.1894965-1-chenfeiyang@loongson.cn Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: "Rafael J. Wysocki" <rafael@kernel.org> Cc: stable@vger.kernel.org # v5.19+
2023-08-25PCI: Tidy config space save/restore messagesBjorn Helgaas
Update config space save/restore debug messages so they line up better. Previously: nvme 0000:05:00.0: saving config space at offset 0x4 (reading 0x20100006) nvme 0000:05:00.0: saving config space at offset 0x8 (reading 0x1080200) nvme 0000:05:00.0: saving config space at offset 0xc (reading 0x0) nvme 0000:05:00.0: restoring config space at offset 0x4 (was 0x0, writing 0x20100006) Now: nvme 0000:05:00.0: save config 0x04: 0x20100006 nvme 0000:05:00.0: save config 0x08: 0x01080200 nvme 0000:05:00.0: save config 0x0c: 0x00000000 nvme 0000:05:00.0: restore config 0x04: 0x00000000 -> 0x20100006 No functional change intended. Enable these messages by setting CONFIG_DYNAMIC_DEBUG=y and adding 'dyndbg="file drivers/pci/* +p"' to kernel parameters. Link: https://lore.kernel.org/r/20230823191831.476579-1-helgaas@kernel.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael@kernel.org>
2023-08-25PCI: Fix typos in docs and commentsBjorn Helgaas
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>
2023-08-25PCI: Fix pci_bus_resetable(), pci_slot_resetable() name typosBjorn Helgaas
Fix typos in the pci_bus_resetable() and pci_slot_resetable() function names. No functional change intended. Link: https://lore.kernel.org/r/20230824193712.542167-10-helgaas@kernel.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2023-08-25PCI: Simplify pci_pio_to_address()Bjorn Helgaas
Simplify pci_pio_to_address() by removing an unnecessary local variable. No functional change intended. Link: https://lore.kernel.org/r/20230824193712.542167-8-helgaas@kernel.org Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2023-08-11PCI: Fix runtime PM race with PME pollingAlex Williamson
Testing that a device is not currently in a low power state provides no guarantees that the device is not imminently transitioning to such a state. Increment the PM usage counter before accessing the device. Since we don't wish to wake the device for PME polling, do so only if the device is already active by using pm_runtime_get_if_active(). Link: https://lore.kernel.org/r/20230803171233.3810944-3-alex.williamson@redhat.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-08-10PCI: Make link retraining use RMW accessors for changing LNKCTLIlpo Järvinen
Don't assume that the device is fully under the control of PCI core. Use RMW capability accessors in link retraining which do proper locking to avoid losing concurrent updates to the register values. Suggested-by: Lukas Wunner <lukas@wunner.de> Fixes: 4ec73791a64b ("PCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratum") Fixes: 7d715a6c1ae5 ("PCI: add PCI Express ASPM support") Link: https://lore.kernel.org/r/20230717120503.15276-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: "Rafael J. Wysocki" <rafael@kernel.org>
2023-06-26Merge branch 'pci/pm'Bjorn Helgaas
- Reduce wait time for secondary bus to be ready to speed up resume (Mika Westerberg) - Avoid putting EloPOS E2/S2/H2 (as well as Elo i2) PCIe Ports in D3cold (Ondrej Zary) - Call _REG when transitioning D-states so AML that uses the PCI config space OpRegion works, which fixes some ASMedia GPIO controllers (Mario Limonciello) * pci/pm: PCI/ACPI: Call _REG when transitioning D-states PCI/ACPI: Validate acpi_pci_set_power_state() parameter PCI/PM: Avoid putting EloPOS E2/S2/H2 PCIe Ports in D3cold PCI/PM: Shorten pci_bridge_wait_for_secondary_bus() wait time for slow links
2023-06-26Merge branch 'pci/enumeration'Bjorn Helgaas
- Add PCI_EXT_CAP_ID_PL_32GT define (Ben Dooks) - Propagate firmware node by calling device_set_node() for better modularity (Andy Shevchenko) - Discover Data Link Layer Link Active Reporting earlier so quirks can take advantage of it (Maciej W. Rozycki) - Use cached Data Link Layer Link Active Reporting capability in pciehp, powerpc/eeh, and mlx5 (Maciej W. Rozycki) - Run quirk for devices that require OS to clear Retrain Link earlier, so later quirks can rely on it (Maciej W. Rozycki) - Export pcie_retrain_link() for use outside ASPM (Maciej W. Rozycki) - Add Data Link Layer Link Active Reporting as another way for pcie_retrain_link() to determine the link is up (Maciej W. Rozycki) - Work around link training failures (especially on the ASMedia ASM2824 switch) by training first at 2.5GT/s and then attempting higher rates (Maciej W. Rozycki) * pci/enumeration: PCI: Add failed link recovery for device reset events PCI: Work around PCIe link training failures PCI: Use pcie_wait_for_link_status() in pcie_wait_for_link_delay() PCI: Add support for polling DLLLA to pcie_retrain_link() PCI: Export pcie_retrain_link() for use outside ASPM PCI: Export PCIe link retrain timeout PCI: Execute quirk_enable_clear_retrain_link() earlier PCI/ASPM: Factor out waiting for link training to complete PCI/ASPM: Avoid unnecessary pcie_link_state use PCI/ASPM: Use distinct local vars in pcie_retrain_link() net/mlx5: Rely on dev->link_active_reporting powerpc/eeh: Rely on dev->link_active_reporting PCI: pciehp: Rely on dev->link_active_reporting PCI: Initialize dev->link_active_reporting earlier PCI: of: Propagate firmware node by calling device_set_node() PCI: Add PCI_EXT_CAP_ID_PL_32GT define # Conflicts: # drivers/pci/pcie/aspm.c
2023-06-23PCI/PM: Avoid putting EloPOS E2/S2/H2 PCIe Ports in D3coldOndrej Zary
The quirk for Elo i2 introduced in commit 92597f97a40b ("PCI/PM: Avoid putting Elo i2 PCIe Ports in D3cold") is also needed by EloPOS E2/S2/H2 which uses the same Continental Z2 board. Change the quirk to match the board instead of system. Link: https://bugzilla.kernel.org/show_bug.cgi?id=215715 Link: https://lore.kernel.org/r/20230614074253.22318-1-linux@zary.sk Signed-off-by: Ondrej Zary <linux@zary.sk> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org
2023-06-20PCI: Add failed link recovery for device reset eventsMaciej W. Rozycki
Request failed link recovery with any upstream PCIe bridge where a device has not come back after reset within PCI_RESET_WAIT time. Reset the polling interval if recovery succeeded, otherwise continue as usual. [bhelgaas: inline pcie_parent_link_retrain()] Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306111631050.64925@angie.orcam.me.uk Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20PCI: Work around PCIe link training failuresMaciej W. Rozycki
Attempt to handle cases such as with a downstream port of the ASMedia ASM2824 PCIe switch where link training never completes and the link continues switching between speeds indefinitely with the data link layer never reaching the active state. It has been observed with a downstream port of the ASMedia ASM2824 Gen 3 switch wired to the upstream port of the Pericom PI7C9X2G304 Gen 2 switch, using a Delock Riser Card PCI Express x1 > 2 x PCIe x1 device, P/N 41433, wired to a SiFive HiFive Unmatched board. In this setup the switches should negotiate a link speed of 5.0GT/s, falling back to 2.5GT/s if necessary. Instead the link continues oscillating between the two speeds, at the rate of 34-35 times per second, with link training reported repeatedly active ~84% of the time. Limiting the target link speed to 2.5GT/s with the upstream ASM2824 device makes the two switches communicate correctly. Removing the speed restriction afterwards makes the two devices switch to 5.0GT/s then. Make use of these observations and detect the inability to train the link by checking for the Data Link Layer Link Active status bit being off while the Link Bandwidth Management Status indicating that hardware has changed the link speed or width in an attempt to correct unreliable link operation. Restrict the speed to 2.5GT/s then with the Target Link Speed field, request a retrain and wait 200ms for the data link to go up. If this is successful, lift the restriction, letting the devices negotiate a higher speed. Also check for a 2.5GT/s speed restriction the firmware may have already arranged and lift it too with ports of devices known to continue working afterwards (currently only ASM2824), that already report their data link being up. [bhelgaas: reorder and squash stubs from https://lore.kernel.org/r/alpine.DEB.2.21.2306111619570.64925@angie.orcam.me.uk to avoid adding stubs that do nothing] Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203022037020.56670@angie.orcam.me.uk/ Link: https://source.denx.de/u-boot/u-boot/-/commit/a398a51ccc68 Link: https://lore.kernel.org/r/alpine.DEB.2.21.2305310038540.59226@angie.orcam.me.uk Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20PCI: Use pcie_wait_for_link_status() in pcie_wait_for_link_delay()Maciej W. Rozycki
Remove a DLLLA status bit polling loop from pcie_wait_for_link_delay() and call almost identical code in pcie_wait_for_link_status() instead. This reduces the lower bound on the polling interval from 10ms to 1ms, possibly increasing the CPU load on the system in favour to reducing the wait time. Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306111611170.64925@angie.orcam.me.uk Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20PCI: Add support for polling DLLLA to pcie_retrain_link()Maciej W. Rozycki
Let the caller of pcie_retrain_link() specify whether they want to use the LT bit or the DLLLA bit of the Link Status Register to determine if link training has completed. It is up to the caller to verify whether the use of the DLLLA bit, the implementation of which is optional, is valid for the device requested. Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306110310540.64925@angie.orcam.me.uk Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20PCI: Export pcie_retrain_link() for use outside ASPMMaciej W. Rozycki
Export pcie_retrain_link() for link retrain needs outside ASPM. Struct pcie_link_state is local to ASPM and only used by pcie_retrain_link() to get at the associated PCI device, so change the operand and adjust the lone call site accordingly. Document the interface. No functional change at this point. Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306110229010.64925@angie.orcam.me.uk Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20PCI: Export PCIe link retrain timeoutMaciej W. Rozycki
Convert LINK_RETRAIN_TIMEOUT from jiffies to milliseconds, accordingly rename to PCIE_LINK_RETRAIN_TIMEOUT_MS, and make available via "pci.h" for the PCI core to use. Use in pcie_wait_for_link_delay(). Link: https://lore.kernel.org/r/alpine.DEB.2.21.2305310030280.59226@angie.orcam.me.uk Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-06PCI/PM: Shorten pci_bridge_wait_for_secondary_bus() wait time for slow linksMika Westerberg
With slow links (<= 5GT/s) active link reporting is not mandatory, so if a device is disconnected during system sleep we might end up waiting for it to respond for ~60s, which slows down resume time. PCIe r6.0, sec 6.6.1, mandates that software must wait for at least 1s before it can assume a device is broken, so use that minimum requirement for slow links and bail out if the device doesn't respond within 1s. However, if the port supports active link reporting we can wait longer as we do with the fast links. This should make system resume time faster for slow links as well while still following the PCIe spec. While there move the PCI_RESET_WAIT constant into pci.c because it is not used outside of that file anymore. Link: https://lore.kernel.org/r/20230425064751.24951-1-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: Lukas Wunner <lukas@wunner.de> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
2023-04-27Merge tag 'driver-core-6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the large set of driver core changes for 6.4-rc1. Once again, a busy development cycle, with lots of changes happening in the driver core in the quest to be able to move "struct bus" and "struct class" into read-only memory, a task now complete with these changes. This will make the future rust interactions with the driver core more "provably correct" as well as providing more obvious lifetime rules for all busses and classes in the kernel. The changes required for this did touch many individual classes and busses as many callbacks were changed to take const * parameters instead. All of these changes have been submitted to the various subsystem maintainers, giving them plenty of time to review, and most of them actually did so. Other than those changes, included in here are a small set of other things: - kobject logging improvements - cacheinfo improvements and updates - obligatory fw_devlink updates and fixes - documentation updates - device property cleanups and const * changes - firwmare loader dependency fixes. All of these have been in linux-next for a while with no reported problems" * tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits) device property: make device_property functions take const device * driver core: update comments in device_rename() driver core: Don't require dynamic_debug for initcall_debug probe timing firmware_loader: rework crypto dependencies firmware_loader: Strip off \n from customized path zram: fix up permission for the hot_add sysfs file cacheinfo: Add use_arch[|_cache]_info field/function arch_topology: Remove early cacheinfo error message if -ENOENT cacheinfo: Check cache properties are present in DT cacheinfo: Check sib_leaf in cache_leaves_are_shared() cacheinfo: Allow early level detection when DT/ACPI info is missing/broken cacheinfo: Add arm64 early level initializer implementation cacheinfo: Add arch specific early level initializer tty: make tty_class a static const structure driver core: class: remove struct class_interface * from callbacks driver core: class: mark the struct class in struct class_interface constant driver core: class: make class_register() take a const * driver core: class: mark class_release() as taking a const * driver core: remove incorrect comment for device_create* MIPS: vpe-cmp: remove module owner pointer from struct class usage. ...
2023-04-20Merge branch 'pci/resource'Bjorn Helgaas
- Add pci_dev_for_each_resource() and pci_bus_for_each_resource() iterators to simplify loops (Andy Shevchenko) * pci/resource: EISA: Drop unused pci_bus_for_each_resource() index argument PCI: Make pci_bus_for_each_resource() index optional PCI: Document pci_bus_for_each_resource() PCI: Introduce pci_dev_for_each_resource() PCI: Introduce pci_resource_n()
2023-04-11PCI/PM: Drop pci_bridge_wait_for_secondary_bus() timeout parameterMika Westerberg
All callers of pci_bridge_wait_for_secondary_bus() supply a timeout of PCIE_RESET_READY_POLL_MS, so drop the parameter. Move the definition of PCIE_RESET_READY_POLL_MS into pci.c, the only user. [bhelgaas: extracted from https://lore.kernel.org/r/20230404052714.51315-3-mika.westerberg@linux.intel.com] Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-04-05PCI: Make pci_bus_for_each_resource() index optionalAndy Shevchenko
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>
2023-03-23driver core: bus: mark the struct bus_type for sysfs callbacks as constantGreg Kroah-Hartman
struct bus_type should never be modified in a sysfs callback as there is nothing in the structure to modify, and frankly, the structure is almost never used in a sysfs callback, so mark it as constant to allow struct bus_type to be moved to read-only memory. Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Bounine <alex.bou9@gmail.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Ben Widawsky <bwidawsk@kernel.org> Cc: Dexuan Cui <decui@microsoft.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Harald Freudenberger <freude@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hu Haowen <src.res@email.cn> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Stuart Yoder <stuyoder@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Yanteng Si <siyanteng@loongson.cn> Acked-by: Ilya Dryomov <idryomov@gmail.com> # rbd Acked-by: Ira Weiny <ira.weiny@intel.com> # cxl Reviewed-by: Alex Shi <alexs@kernel.org> Acked-by: Iwona Winiarska <iwona.winiarska@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> # pci Acked-by: Wei Liu <wei.liu@kernel.org> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> # scsi Link: https://lore.kernel.org/r/20230313182918.1312597-23-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-24Merge tag 'pci-v6.3-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci Pull PCI updates from Bjorn Helgaas: "Enumeration: - Rework portdrv shutdown so it disables interrupts but doesn't disable bus mastering, which leads to hangs on Loongson LS7A - Add mechanism to prevent Max_Read_Request_Size (MRRS) increases, again to avoid hardware issues on Loongson LS7A (and likely other devices based on DesignWare IP) - Ignore devices with a firmware (DT or ACPI) node that says the device is disabled Resource management: - Distribute spare resources to unconfigured hotplug bridges at boot-time (not just when hot-adding such a bridge), which makes hot-adding devices to docks work better. Tried this in v6.1 but had to revert for regressions, so try again - Fix root bus issue that dropped resources that happened to end at 0, e.g., [bus 00] PCI device hotplug: - Remove device locking when marking device as disconnected so this doesn't have to wait for concurrent driver bind/unbind to complete - Quirk more Qualcomm bridges that don't fully implement the PCIe Slot Status 'Command Completed' bit Power management: - Account for _S0W of the target bridge in acpi_pci_bridge_d3() so we don't miss hot-add notifications for USB4 docks, Thunderbolt, etc Reset: - Observe delay after reset, e.g., resuming from system sleep, regardless of whether a bridge can suspend to D3cold at runtime - Wait for secondary bus to become ready after a bridge reset Virtualization: - Avoid FLR on some AMD FCH AHCI adapters where it doesn't work - Allow independent IOMMU groups for some Wangxun NICs that prevent peer-to-peer transactions but don't advertise an ACS Capability Error handling: - Configure End-to-End-CRC (ECRC) only if Linux owns the AER Capability - Remove redundant Device Control Error Reporting Enable in the AER service driver since this is already done for all devices during enumeration ASPM: - Add pci_enable_link_state() interface to allow drivers to enable ASPM link state Endpoint framework: - Move dra7xx and tegra194 linkup processing from hard IRQ to threaded IRQ handler - Add a separate lock for endpoint controller list of endpoint function drivers to prevent deadlock in callbacks - Pass events from endpoint controller to endpoint function drivers via callbacks instead of notifiers Synopsys DesignWare eDMA controller driver (acked by Vinod): - Fix CPU vs PCI address issues - Fix source vs destination address issues - Fix issues with interleaved transfer semantics - Fix channel count initialization issue (issue still exists in several other drivers) - Clean up and improve debugfs usage so it will work on platforms with several eDMA devices Baikal T-1 PCIe controller driver: - Set a 64-bit DMA mask Freescale i.MX6 PCIe controller driver: - Add i.MX8MM, i.MX8MQ, i.MX8MP endpoint mode DT binding and driver support Intel VMD host bridge driver: - Add quirk to configure PCIe ASPM and LTR. This is normally done by BIOS, and will be for future products Marvell MVEBU PCIe controller driver: - Mark this driver as broken in Kconfig since bugs prevent its daily usage MediaTek MT7621 PCIe controller driver: - Delay PHY port initialization to improve boot reliability for ZBT WE1326, ZBT WF3526-P, and some Netgear models Qualcomm PCIe controller driver: - Add MSM8998 DT compatible string - Unify MSM8996 and MSM8998 clock orderings - Add SM8350 DT binding and driver support - Add IPQ8074 Gen3 DT binding and driver support - Correct qcom,perst-regs in DT binding - Add qcom_pcie_host_deinit() so the PHY is powered off and regulators and clocks are disabled on late host-init errors Socionext UniPhier Pro5 controller driver: - Clean up uniphier-ep reg, clocks, resets, and their names in DT binding Synopsys DesignWare PCIe controller driver: - Restrict coherent DMA mask to 32 bits for MSI, but allow controller drivers to set 64-bit streaming DMA mask - Add eDMA engine support in both Root Port and Endpoint controllers Miscellaneous: - Remove MODULE_LICENSE from boolean drivers so they don't look like modules so modprobe can complain about them" * tag 'pci-v6.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (86 commits) PCI: dwc: Add Root Port and Endpoint controller eDMA engine support PCI: bt1: Set 64-bit DMA mask PCI: dwc: Restrict only coherent DMA mask for MSI address allocation dmaengine: dw-edma: Prepare dw_edma_probe() for builtin callers dmaengine: dw-edma: Depend on DW_EDMA instead of selecting it dmaengine: dw-edma: Add mem-mapped LL-entries support PCI: Remove MODULE_LICENSE so boolean drivers don't look like modules PCI: hv: Drop duplicate PCI_MSI dependency PCI/P2PDMA: Annotate RCU dereference PCI/sysfs: Constify struct kobj_type pci_slot_ktype PCI: hotplug: Allow marking devices as disconnected during bind/unbind PCI: pciehp: Add Qualcomm quirk for Command Completed erratum PCI: qcom: Add IPQ8074 Gen3 port support dt-bindings: PCI: qcom: Add IPQ8074 Gen3 port dt-bindings: PCI: qcom: Sort compatibles alphabetically PCI: qcom: Fix host-init error handling PCI: qcom: Add SM8350 support dt-bindings: PCI: qcom: Add SM8350 dt-bindings: PCI: qcom-ep: Correct qcom,perst-regs dt-bindings: PCI: qcom: Unify MSM8996 and MSM8998 clock order ...
2023-02-22Merge branch 'pci/reset'Bjorn Helgaas
- Always observe reset delay when waking devices from D3cold, e.g., after system sleep, regardless of whether we're allowed to runtime-suspend to D3cold (Lukas Wunner) - Unify reset and resume delays to wait for downstream devices after a bridge reset (Lukas Wunner) - Wait for downstream devices after a DPC-induced bridge reset (Lukas Wunner) * pci/reset: PCI/DPC: Await readiness of secondary bus after reset PCI: Unify delay handling for reset and resume PCI/PM: Observe reset delay irrespective of bridge_d3
2023-02-10Revert "PCI/ASPM: Save L1 PM Substates Capability for suspend/resume"Bjorn Helgaas
This reverts commit 4ff116d0d5fd8a025604b0802d93a2d5f4e465d1. Tasev Nikola and Mark Enriquez reported that resume from suspend was broken in v6.1-rc1. Tasev bisected to a47126ec29f5 ("PCI/PTM: Cache PTM Capability offset"), but we can't figure out how that could be related. Mark saw the same symptoms and bisected to 4ff116d0d5fd ("PCI/ASPM: Save L1 PM Substates Capability for suspend/resume"), which does have a connection: it restores L1 Substates configuration while ASPM L1 may be enabled: pci_restore_state pci_restore_aspm_l1ss_state aspm_program_l1ss pci_write_config_dword(PCI_L1SS_CTL1, ctl1) # L1SS restore pci_restore_pcie_state pcie_capability_write_word(PCI_EXP_LNKCTL, cap[i++]) # L1 restore which is a problem because PCIe r6.0, sec 5.5.4, requires that: If setting either or both of the enable bits for ASPM L1 PM Substates, both ports must be configured as described in this section while ASPM L1 is disabled. Separately, Thomas Witt reported that 5e85eba6f50d ("PCI/ASPM: Refactor L1 PM Substates Control Register programming") broke suspend/resume, and it depends on 4ff116d0d5fd. Revert 4ff116d0d5fd ("PCI/ASPM: Save L1 PM Substates Capability for suspend/resume") to fix the resume issue and enable revert of 5e85eba6f50d to fix the issue Thomas reported. Note that reverting 4ff116d0d5fd means L1 Substates config may be lost on suspend/resume. As far as we know the system will use more power but will still *work* correctly. Fixes: 4ff116d0d5fd ("PCI/ASPM: Save L1 PM Substates Capability for suspend/resume") Link: https://bugzilla.kernel.org/show_bug.cgi?id=216782 Link: https://bugzilla.kernel.org/show_bug.cgi?id=216877 Reported-by: Tasev Nikola <tasev.stefanoska@skynet.be> Reported-by: Mark Enriquez <enriquezmark36@gmail.com> Reported-by: Thomas Witt <kernel@witt.link> Tested-by: Mark Enriquez <enriquezmark36@gmail.com> Tested-by: Thomas Witt <kernel@witt.link> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org # v6.1+ Cc: Vidya Sagar <vidyas@nvidia.com>
2023-02-09PCI/DPC: Await readiness of secondary bus after resetLukas Wunner
pci_bridge_wait_for_secondary_bus() is called after a Secondary Bus Reset, but not after a DPC-induced Hot Reset. As a result, the delays prescribed by PCIe r6.0 sec 6.6.1 are not observed and devices on the secondary bus may be accessed before they're ready. One affected device is Intel's Ponte Vecchio HPC GPU. It comprises a PCIe switch whose upstream port is not immediately ready after reset. Because its config space is restored too early, it remains in D0uninitialized, its subordinate devices remain inaccessible and DPC recovery fails with messages such as: i915 0000:8c:00.0: can't change power state from D3cold to D0 (config space inaccessible) intel_vsec 0000:8e:00.1: can't change power state from D3cold to D0 (config space inaccessible) pcieport 0000:89:02.0: AER: device recovery failed Fix it. Link: https://lore.kernel.org/r/9f5ff00e1593d8d9a4b452398b98aa14d23fca11.1673769517.git.lukas@wunner.de Tested-by: Ravi Kishore Koppuravuri <ravi.kishore.koppuravuri@intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: stable@vger.kernel.org
2023-02-07PCI: Unify delay handling for reset and resumeLukas Wunner
Sheng Bi reports that pci_bridge_secondary_bus_reset() may fail to wait for devices on the secondary bus to become accessible after reset: Although it does call pci_dev_wait(), it erroneously passes the bridge's pci_dev rather than that of a child. The bridge of course is always accessible while its secondary bus is reset, so pci_dev_wait() returns immediately. Sheng Bi proposes introducing a new pci_bridge_secondary_bus_wait() function which is called from pci_bridge_secondary_bus_reset(): https://lore.kernel.org/linux-pci/20220523171517.32407-1-windy.bi.enflame@gmail.com/ However we already have pci_bridge_wait_for_secondary_bus() which does almost exactly what we need. So far it's only called on resume from D3cold (which implies a Fundamental Reset per PCIe r6.0 sec 5.8). Re-using it for Secondary Bus Resets is a leaner and more rational approach than introducing a new function. That only requires a few minor tweaks: - Amend pci_bridge_wait_for_secondary_bus() to await accessibility of the first device on the secondary bus by calling pci_dev_wait() after performing the prescribed delays. pci_dev_wait() needs two parameters, a reset reason and a timeout, which callers must now pass to pci_bridge_wait_for_secondary_bus(). The timeout is 1 sec for resume (PCIe r6.0 sec 6.6.1) and 60 sec for reset (commit 821cdad5c46c ("PCI: Wait up to 60 seconds for device to become ready after FLR")). Introduce a PCI_RESET_WAIT macro for the 1 sec timeout. - Amend pci_bridge_wait_for_secondary_bus() to return 0 on success or -ENOTTY on error for consumption by pci_bridge_secondary_bus_reset(). - Drop an unnecessary 1 sec delay from pci_reset_secondary_bus() which is now performed by pci_bridge_wait_for_secondary_bus(). A static delay this long is only necessary for Conventional PCI, so modern PCIe systems benefit from shorter reset times as a side effect. Fixes: 6b2f1351af56 ("PCI: Wait for device to become ready after secondary bus reset") Link: https://lore.kernel.org/r/da77c92796b99ec568bd070cbe4725074a117038.1673769517.git.lukas@wunner.de Reported-by: Sheng Bi <windy.bi.enflame@gmail.com> Tested-by: Ravi Kishore Koppuravuri <ravi.kishore.koppuravuri@intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Cc: stable@vger.kernel.org # v4.17+
2023-02-07PCI/PM: Observe reset delay irrespective of bridge_d3Lukas Wunner
If a PCI bridge is suspended to D3cold upon entering system sleep, resuming it entails a Fundamental Reset per PCIe r6.0 sec 5.8. The delay prescribed after a Fundamental Reset in PCIe r6.0 sec 6.6.1 is sought to be observed by: pci_pm_resume_noirq() pci_pm_bridge_power_up_actions() pci_bridge_wait_for_secondary_bus() However, pci_bridge_wait_for_secondary_bus() bails out if the bridge_d3 flag is not set. That flag indicates whether a bridge is allowed to suspend to D3cold at *runtime*. Hence *no* delay is observed on resume from system sleep if runtime D3cold is forbidden. That doesn't make any sense, so drop the bridge_d3 check from pci_bridge_wait_for_secondary_bus(). The purpose of the bridge_d3 check was probably to avoid delays if a bridge remained in D0 during suspend. However the sole caller of pci_bridge_wait_for_secondary_bus(), pci_pm_bridge_power_up_actions(), is only invoked if the previous power state was D3cold. Hence the additional bridge_d3 check seems superfluous. Fixes: ad9001f2f411 ("PCI/PM: Add missing link delays required by the PCIe spec") Link: https://lore.kernel.org/r/eb37fa345285ec8bacabbf06b020b803f77bdd3d.1673769517.git.lukas@wunner.de Tested-by: Ravi Kishore Koppuravuri <ravi.kishore.koppuravuri@intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Cc: stable@vger.kernel.org # v5.5+
2023-02-01PCI: loongson: Prevent LS7A MRRS increasesHuacai Chen
Except for isochronous-configured devices, software may set Max_Read_Request_Size (MRRS) to any value up to 4096. If a device issues a read request with size greater than the completer's Max_Payload_Size (MPS), the completer is required to break the response into multiple completions. Instead of correctly responding with multiple completions to a large read request, some LS7A Root Ports respond with a Completer Abort. To prevent this, the MRRS must be limited to an implementation-specific value. The OS cannot detect that value, so rely on BIOS to configure MRRS before booting, and quirk the Root Ports so we never set an MRRS larger than that BIOS value for any downstream device. N.B. Hot-added devices are not configured by BIOS, and they power up with MRRS = 512 bytes, so these devices will be limited to 512 bytes. If the LS7A limit is smaller, those hot-added devices may not work correctly, but per [1], hotplug is not supported with this chipset revision. [1] https://lore.kernel.org/r/073638a7-ae68-2847-ac3d-29e5e760d6af@loongson.cn [bhelgaas: commit log] Link: https://bugzilla.kernel.org/show_bug.cgi?id=216884 Link: https://lore.kernel.org/r/20230201043018.778499-3-chenhuacai@loongson.cn Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-11-11PCI: Fix pci_device_is_present() for VFs by checking PFMichael S. Tsirkin
pci_device_is_present() previously didn't work for VFs because it reads the Vendor and Device ID, which are 0xffff for VFs, which looks like they aren't present. Check the PF instead. Wei Gong reported that if virtio I/O is in progress when the driver is unbound or "0" is written to /sys/.../sriov_numvfs, the virtio I/O operation hangs, which may result in output like this: task:bash state:D stack: 0 pid: 1773 ppid: 1241 flags:0x00004002 Call Trace: schedule+0x4f/0xc0 blk_mq_freeze_queue_wait+0x69/0xa0 blk_mq_freeze_queue+0x1b/0x20 blk_cleanup_queue+0x3d/0xd0 virtblk_remove+0x3c/0xb0 [virtio_blk] virtio_dev_remove+0x4b/0x80 ... device_unregister+0x1b/0x60 unregister_virtio_device+0x18/0x30 virtio_pci_remove+0x41/0x80 pci_device_remove+0x3e/0xb0 This happened because pci_device_is_present(VF) returned "false" in virtio_pci_remove(), so it called virtio_break_device(). The broken vq meant that vring_interrupt() skipped the vq.callback() that would have completed the virtio I/O operation via virtblk_done(). [bhelgaas: commit log, simplify to always use pci_physfn(), add stable tag] Link: https://lore.kernel.org/r/20221026060912.173250-1-mst@redhat.com Reported-by: Wei Gong <gongwei833x@gmail.com> Tested-by: Wei Gong <gongwei833x@gmail.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org
2022-11-08PCI: Assign PCI domain IDs by ida_alloc()Pali Rohár
Replace assignment of PCI domain IDs from atomic_inc_return() to ida_alloc(). Use two IDAs, one for static domain allocations (those which are defined in device tree) and second for dynamic allocations (all other). During removal of root bus / host bridge, also release the domain ID. The released ID can be reused again, for example when dynamically loading and unloading native PCI host bridge drivers. This change also allows to mix static device tree assignment and dynamic by kernel as all static allocations are reserved in dynamic pool. [bhelgaas: set "err" if "bus->domain_nr < 0"] Link: https://lore.kernel.org/r/20220714184130.5436-1-pali@kernel.org Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-10-05Merge branch 'pci/pm'Bjorn Helgaas
- Cache the PTM capability offset instead of searching for it every time (Bjorn Helgaas) - Separate PTM configuration from PTM enable (Bjorn Helgaas) - Add pci_suspend_ptm() and pci_resume_ptm() to disable and re-enable PTM on suspend/resume so some Root Ports can safely enter a lower-power PM state (Bjorn Helgaas) - Disable PTM for all devices during suspend; previously we only did this for Root Ports and even then only in certain cases (Bjorn Helgaas) - Simplify pci_pm_suspend_noirq() (Rajvi Jingar) - Reduce the delay after transitions to/from D3hot by using usleep_range() instead of msleep(), which reduces the typical delay from 19ms to 10ms (Sajid Dalvi, Will McVicker) * pci/pm: PCI/PM: Reduce D3hot delay with usleep_range() PCI/PM: Simplify pci_pm_suspend_noirq() PCI/PM: Always disable PTM for all devices during suspend PCI/PTM: Consolidate PTM interface declarations PCI/PTM: Reorder functions in logical order PCI/PTM: Preserve RsvdP bits in PTM Control register PCI/PTM: Move pci_ptm_info() body into its only caller PCI/PTM: Add pci_suspend_ptm() and pci_resume_ptm() PCI/PTM: Separate configuration and enable PCI/PTM: Add pci_upstream_ptm() helper PCI/PTM: Cache PTM Capability offset
2022-10-04PCI/ASPM: Save L1 PM Substates Capability for suspend/resumeVidya Sagar
Previously the L1 PM Substates Control Registers (CTL1 and CTL2) weren't saved and restored during suspend/resume leading to the L1 PM Substates configuration being lost post-resume. Save the L1 PM Substates Control Registers so that the configuration is retained post-resume. [bhelgaas: drop pci_is_pcie() testing; we can rely on pci_configure_ltr() having already done that] Link: https://lore.kernel.org/r/20220913131822.16557-3-vidyas@nvidia.com Signed-off-by: Vidya Sagar <vidyas@nvidia.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-09-29PCI/PM: Reduce D3hot delay with usleep_range()Sajid Dalvi
PCIe r6.0, sec 5.9, requires a 10ms delay between programming a device to change to or from D3hot and the time the device is next accessed (unless Readiness Notifications are used). The 10ms value (PCI_PM_D3HOT_WAIT) doesn't appear directly here because some chipsets require 120ms for devices *below* them (pci_pm_d3hot_delay) and some devices require more or less than 10ms (dev->d3hot_delay). But msleep(10) typically waits about *20*ms, which is more than we need. Switch to usleep_range() to improve the delay accuracy. Based on a commit from Sajid in the Pixel 6 kernel tree [1]. On a Pixel 6, the 10ms delay for the Exynos PCIe device delayed for an average of 19ms. Switching to usleep_range() decreased the resume time by about 9ms. [1] https://android.googlesource.com/kernel/gs/+/18a8cad68d8e6d50f339a716a18295e6d987cee3 [bhelgaas commit log, add timers-howto.rst link] Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/timers/timers-howto.rst?id=v5.19#n73 Link: https://lore.kernel.org/r/20220921212735.2131588-1-willmcvicker@google.com Signed-off-by: Sajid Dalvi <sdalvi@google.com> Signed-off-by: Will McVicker <willmcvicker@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
2022-09-12PCI/PM: Always disable PTM for all devices during suspendBjorn Helgaas
We want to disable PTM on Root Ports because that allows some chips, e.g., Intel mobile chips since Coffee Lake, to enter a lower-power PM state. That means we also have to disable PTM on downstream devices. PCIe r6.0, sec 2.2.8, recommends that functions support generation of messages in non-D0 states, so we have to assume Switch Upstream Ports or Endpoints may send PTM Requests while in D1, D2, and D3hot. A PTM message received by a Downstream Port (including a Root Port) with PTM disabled must be treated as an Unsupported Request (sec 6.21.3). PTM was previously disabled only for Root Ports, and it was disabled in pci_prepare_to_sleep(), which is not called at all if a driver supports legacy PM or does its own state saving. Instead, disable PTM early in pci_pm_suspend() and pci_pm_runtime_suspend() so we do it in all cases. Previously PTM was disabled *after* saving device state, so the state restore on resume automatically re-enabled it. Since we now disable PTM *before* saving state, we must explicitly re-enable it in pci_pm_resume() and pci_pm_runtime_resume(). Here's a sample of errors that occur when PTM is disabled only on the Root Port. With this topology: 0000:00:1d.0 Root Port to [bus 08-71] 0000:08:00.0 Switch Upstream Port to [bus 09-71] Kai-Heng reported errors like this: pcieport 0000:00:1d.0: [20] UnsupReq (First) pcieport 0000:00:1d.0: AER: TLP Header: 34000000 08000052 00000000 00000000 Decoding TLP header 0x34...... (0011 0100b) and 0x08000052: Fmt 001b 4 DW header, no data Type 1 0100b Msg (Local - Terminate at Receiver) Requester ID 0x0800 Bus 08 Devfn 00.0 Message Code 0x52 0101 0010b PTM Request The 00:1d.0 Root Port logged an Unsupported Request error when it received a PTM Request with Requester ID 08:00.0. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215453 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216210 Fixes: a697f072f5da ("PCI: Disable PTM during suspend to save power") Link: https://lore.kernel.org/r/20220909202505.314195-10-helgaas@kernel.org Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com> Tested-by: Rajvi Jingar <rajvi.jingar@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2022-09-12PCI/PTM: Add pci_suspend_ptm() and pci_resume_ptm()Bjorn Helgaas
We disable PTM during suspend because that allows some Root Ports to enter lower-power PM states, which means we also need to disable PTM for all downstream devices. Add pci_suspend_ptm() and pci_resume_ptm() for this purpose. pci_enable_ptm() and pci_disable_ptm() are for drivers to use to enable or disable PTM. They use dev->ptm_enabled to keep track of whether PTM should be enabled. pci_suspend_ptm() and pci_resume_ptm() are PCI core-internal functions to temporarily disable PTM during suspend and (depending on dev->ptm_enabled) re-enable PTM during resume. Enable/disable/suspend/resume all use internal __pci_enable_ptm() and __pci_disable_ptm() functions that only update the PTM Control register. Outline: pci_enable_ptm(struct pci_dev *dev) { __pci_enable_ptm(dev); dev->ptm_enabled = 1; pci_ptm_info(dev); } pci_disable_ptm(struct pci_dev *dev) { if (dev->ptm_enabled) { __pci_disable_ptm(dev); dev->ptm_enabled = 0; } } pci_suspend_ptm(struct pci_dev *dev) { if (dev->ptm_enabled) __pci_disable_ptm(dev); } pci_resume_ptm(struct pci_dev *dev) { if (dev->ptm_enabled) __pci_enable_ptm(dev); } Nothing currently calls pci_resume_ptm(); the suspend path saves the PTM state before disabling PTM, so the PTM state restore in the resume path implicitly re-enables it. A future change will use pci_resume_ptm() to fix some problems with this approach. Link: https://lore.kernel.org/r/20220909202505.314195-5-helgaas@kernel.org Tested-by: Rajvi Jingar <rajvi.jingar@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
generated by cgit v1.2.3 (git 2.39.1) at 2025-08-02 11:57:52 +0000