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>
This commit is contained in:
Dan Williams
2020-07-20 15:08:24 -07:00
committed by Vishal Verma
parent 48001ea50d
commit a1facc1fff
7 changed files with 461 additions and 7 deletions

View File

@@ -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