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| author | Dan Williams <dan.j.williams@intel.com> | 2020-07-21 00:08:24 +0200 |
|---|---|---|
| committer | Vishal Verma <vishal.l.verma@intel.com> | 2020-07-29 03:29:22 +0200 |
| commit | a1facc1fffc17a65e2c12a8de7434b9325ec0324 (patch) | |
| tree | 1b12e0e5e163bb3a4f8adcb0344c9f5a36801a1e /Documentation/ABI/testing/sysfs-bus-nfit | |
| parent | PM, libnvdimm: Add runtime firmware activation support (diff) | |
| download | linux-a1facc1fffc17a65e2c12a8de7434b9325ec0324.tar.xz linux-a1facc1fffc17a65e2c12a8de7434b9325ec0324.zip | |
ACPI: NFIT: Add runtime firmware activate support
Plumb the platform specific backend for the generic libnvdimm firmware
activate interface. Register dimm level operations to arm/disarm
activation, and register bus level operations to report the dynamic
platform-quiesce time relative to the number of dimms armed for firmware
activation.
A new nfit-specific bus attribute "firmware_activate_noidle" is added to
allow the activation to switch between platform enforced, and OS
opportunistic device quiesce. In other words, let the hibernate cycle
handle in-flight device-dma rather than the platform attempting to
increase PCI-E timeouts and the like.
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Diffstat (limited to 'Documentation/ABI/testing/sysfs-bus-nfit')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-nfit | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-nfit b/Documentation/ABI/testing/sysfs-bus-nfit index a1cb44dcb908..e4f76e7eab93 100644 --- a/Documentation/ABI/testing/sysfs-bus-nfit +++ b/Documentation/ABI/testing/sysfs-bus-nfit @@ -202,6 +202,25 @@ Description: functions. See the section named 'NVDIMM Root Device _DSMs' in the ACPI specification. +What: /sys/bus/nd/devices/ndbusX/nfit/firmware_activate_noidle +Date: Apr, 2020 +KernelVersion: v5.8 +Contact: linux-nvdimm@lists.01.org +Description: + (RW) The Intel platform implementation of firmware activate + support exposes an option let the platform force idle devices in + the system over the activation event, or trust that the OS will + do it. The safe default is to let the platform force idle + devices since the kernel is already in a suspend state, and on + the chance that a driver does not properly quiesce bus-mastering + after a suspend callback the platform will handle it. However, + the activation might abort if, for example, platform firmware + determines that the activation time exceeds the max PCI-E + completion timeout. Since the platform does not know whether the + OS is running the activation from a suspend context it aborts, + but if the system owner trusts driver suspend callback to be + sufficient then 'firmware_activation_noidle' can be + enabled to bypass the activation abort. What: /sys/bus/nd/devices/regionX/nfit/range_index Date: Jun, 2015 |