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| author | Keith Busch <kbusch@kernel.org> | 2024-10-25 15:27:54 -0700 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2024-11-13 16:43:34 -0600 |
| commit | 2fa046449a82a7d0f6d9721dd83e348816038444 (patch) | |
| tree | a0fd994dd816d1da3e5f6ad0f0c30fff194d9e3f /Documentation/ABI | |
| parent | 9852d85ec9d492ebef56dc5f229416c925758edc (diff) | |
| download | linux-2fa046449a82a7d0f6d9721dd83e348816038444.tar.gz linux-2fa046449a82a7d0f6d9721dd83e348816038444.tar.bz2 linux-2fa046449a82a7d0f6d9721dd83e348816038444.zip | |
PCI: Add 'reset_subordinate' to reset hierarchy below bridge
The "bus" and "cxl_bus" reset methods reset a device by asserting Secondary
Bus Reset on the bridge leading to the device. These only work if the
device is the only device below the bridge.
Add a sysfs 'reset_subordinate' attribute on bridges that can assert
Secondary Bus Reset regardless of how many devices are below the bridge.
This resets all the devices below a bridge in a single command, including
the locking and config space save/restore that reset methods normally do.
This may be the only way to reset devices that don't support other reset
methods (ACPI, FLR, PM reset, etc).
Link: https://lore.kernel.org/r/20241025222755.3756162-1-kbusch@meta.com
Signed-off-by: Keith Busch <kbusch@kernel.org>
[bhelgaas: commit log, add capable(CAP_SYS_ADMIN) check]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Amey Narkhede <ameynarkhede03@gmail.com>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-pci | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 7f63c7e97773..5da6a14dc326 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -163,6 +163,17 @@ Description: will be present in sysfs. Writing 1 to this file will perform reset. +What: /sys/bus/pci/devices/.../reset_subordinate +Date: October 2024 +Contact: linux-pci@vger.kernel.org +Description: + This is visible only for bridge devices. If you want to reset + all devices attached through the subordinate bus of a specific + bridge device, writing 1 to this will try to do it. This will + affect all devices attached to the system through this bridge + similiar to writing 1 to their individual "reset" file, so use + with caution. + What: /sys/bus/pci/devices/.../vpd Date: February 2008 Contact: Ben Hutchings <bwh@kernel.org> |