src/sys/dev/pci, branch release/14.4.0

pci_iov: Support dynamic subordinate bus growth during VF creation

2026-01-29T15:22:37Z

Certain SR-IOV devices enumerate Virtual Functions (VFs) on a different PCIe bus than their parent Physical Function (PF). In such cases, the default subordinate bus range assigned by BIOS may be insufficient to cover all VFs. This patch dynamically expands the subordinate bus range by: - Allocating additional bus numbers using bus_alloc_resource() when VFs are initialized - Releasing the reserved bus range during VF deletion via bus_release_resource() Reviewed by: jhb (cherry picked from commit f7951799877c16cb901be1acc8d6643f0693cec4)

pci: add quirk to disable Function-Level Reset (FLR)

2026-01-16T19:37:50Z

MediaTek mt76 WiFi cards are advertising FLR support but after issuing a FLR the chipset is gone. Add a quirk so we can disable FLR. The current reset code will automatically fall back to a power reset. This makes the card show up under bhyve where before it would just not be discovered at all. That should make wifibox work for it and will help development for a LinuxKPI based mt76 driver as found in framework laptops as no dedicated machine and constant reboots are needed anymore. We will likely need to add more PCI vendor/device IDs once we can test the other device IDs. After a lot of help from: jhb Really implemented by: jhb (I just typed and tested) GH issue: github.com/pgj/freebsd-wifibox/issues/73 Reviewed by: imp, emaste Differential Revision: https://reviews.freebsd.org/D52728 (cherry picked from commit 4c0e53aced2251eb5ac7eca44e13a6b947be8582) (cherry picked from commit 3bd015a1a918d060dbef556ddfa6e236f5212330)

pci/n1sdp: Disable HotPlug

2026-01-14T21:14:10Z

Work around an issue when HotPlug is enabled where pcib3 and pcib5 continuously report the following: pcib3: HotPlug interrupt: 0x30 pcib3: Command Completed pcib3: HotPlug interrupt: 0x30 pcib3: Command Completed ... As a workaround disable HotPlug on the N1SDP as it's unlikely anyone will depend on it. Reviewed by: br Fixes: 1f5c50a86173 ("pci_host_generic:Add pcib_request_feature on ACPI") Sponsored by: Arm Ltd Differential Revision: https://reviews.freebsd.org/D53134 (cherry picked from commit edbbf26e2650e02cd3925dd1deaacf9b8fb2e2a0)

pcib: Clear any pending slot status events during attach

2025-04-29T14:46:40Z

Any events left over from boot firmware, etc. are not meaningful so clear pending events during attach. If they are still pending they should remain asserted when the slot status register is re-read. Reviewed by: imp Differential Revision: https://reviews.freebsd.org/D49950 (cherry picked from commit ff45e4759a38f44a0199b2948b7b1e987e7c71da)

pcib: Ignore power fault detected if a power controller is not present

2025-04-29T14:46:26Z

At least some PCI-express bridges exposed by Intel Volume Management Devices report bogus power faults in their slot status register. As a workaround, ignore the power fault detected flag if the slot capability register does not indicate support for a power controller. While the PCI-e spec does not explicitly state that the PFD flag should always be zero if a power controller is not present, parts of the spec do seem to assume this. For example, the flag is included in the "Power Controller Registers" register group in 6.7.2.4, and the definition of the value for this flag seems to presume the presence of a power controller: If a Power Controller that supports power fault detection is implemented, this bit is Set when the Power Controller detects a power fault at this slot. Note that, depending on hardware capability, it is possible that a power fault can be detected at any time, independent of the Power Controller Control setting or the occupancy of the slot. If power fault detection is not supported, this bit must not be Set. PR: 285993 Reported by: Jim Long Reviewed by: imp Differential Revision: https://reviews.freebsd.org/D49949 (cherry picked from commit 4c8b9f40cda7dd6b2de547b288d712c85998ce11)

pci: Add helper routines to manage PME in device drivers

2025-04-29T14:44:58Z

pci_has_pm is a quick check that returns true if a PCI device supports the power management capability. pci_enable_pme can be used in DEVICE_SUSPEND driver methods to enable PME# during suspend. Reviewed by: Krzysztof Galazka x Differential Revision: https://reviews.freebsd.org/D49250 (cherry picked from commit e5cbf0e881fa1851912be77c62aa7ab17f844c3d)

pci: Clear active PME# and disable PME# generation

2025-04-29T14:44:25Z

The PCI power management specification requires that the OS clear any pending PME# interrupt and generation of PME# interrupts during "initial operating system load". Note that clearing a pending PME# interrupt requires writing a 1 to the Read/Write-Clear PME bit in the power management status register. To handle the boot time case, clear PME# state in pci_read_cap() when scanning new PCI devices. This should also cover hotplug devices. In addition, clear this state on every PCI device after resume from sleep in pci_resume_child before invoking the driver's DEVICE_RESUME method. Reviewed by: imp Differential Revision: https://reviews.freebsd.org/D49222 (cherry picked from commit 82d692771239f1d156a875087dff4cf09f0e8b80)

pcib: Use taskqueue_bus for hot-plug events instead of a private taskqueue

2025-04-29T14:36:16Z

Reviewed by: imp Differential Revision: https://reviews.freebsd.org/D49269 (cherry picked from commit b23314ecb99cedef1090bdaa486fbd25aa5a9558)

pci: Don't cache the count of MSI/MSI-X messages before allocation

2025-04-29T14:24:32Z

A device can in theory change the read-only fields in the MSI/MSI-X control registers that indicate the maximum number of supported registers in response to changing other device registers. For example, certain Intel networking VFs change the number of messages as a result of changes in the PCI_IOV_ADD_VF callback. To support this, always read the current value of the relevant control register in the *_count and *_alloc methods. Once messages have been allocated, the control register value remains cached. Reported by: Krzysztof Galazka Reviewed by: Krzysztof Galazka , erj Differential Revision: https://reviews.freebsd.org/D48890 (cherry picked from commit 346020138a0fd20085ebc285f090df38d7d18527)

pci: Cosmetic cleanups to MSI/MSI-X routines

2025-04-29T14:24:10Z

- Use unsigned integers for various variables. The count argument to the alloc method as well as the IRQ values used with the pcib_if.m methods should also be unsigned eventually. - Use mallocarray to allocate arrays - Use bool in a few places Reviewed by: Krzysztof Galazka Differential Revision: https://reviews.freebsd.org/D48889 (cherry picked from commit a3835cceb0882494628d5d075f99a86bd3464672)