driver-api/nvdimm/firmware-activate.rst

1 .. SPDX-License-Identifier: GPL-2.0
8 "DIMM" to perform tasks like media management, capacity provisioning,
10 involves a reboot because it has implications for in-flight memory
16 A native sysfs interface is implemented in libnvdimm to allow platform
17 to advertise and control their local runtime firmware activation
20 The libnvdimm bus object, ndbusX, implements an ndbusX/firmware/activate
24 - idle:
25   No devices are set / armed to activate firmware
27 - armed:
30 - busy:
32   back to idle and completing an activation cycle.
34 - overflow:
35   If the platform has a concept of incremental work needed to perform
37   activation. In that scenario the potential for firmware activation to
40 The 'ndbusX/firmware/activate' property can be written with a value of
41 either 'live', or 'quiesce'. A value of 'quiesce' triggers the kernel to
43 'freeze' state where drivers and applications are notified to stop their
46 'ndbusX/firmware/activate' property will be elided completely if no
51 does not require or inflict any quiesce period on the system to update
54 may still be written to 'ndbusX/firmware/activate' as an override to
55 assume the risk of racing firmware update with in-flight device and
59 The libnvdimm memory-device / DIMM object, nmemX, implements
60 'nmemX/firmware/activate' and 'nmemX/firmware/result' attributes to
61 communicate the per-device firmware activation state. Similar to the
62 'ndbusX/firmware/activate' attribute, the 'nmemX/firmware/activate'
64 from 'armed' to 'idle' when the system is prepared to activate firmware,
65 firmware staged + state set to armed, and 'ndbusX/firmware/activate' is
69 - none:
72 - success:
75 - fail:
76   The last runtime activation failed for device-specific reasons.
78 - not_staged:
79   The last runtime activation failed due to a sequencing error of the
82 - need_reset:
84   activated via the legacy method of power-cycling the system.
86 [1]: https://docs.pmem.io/persistent-memory/