Add support for simple NVDIMM v1.2 namespaces from the UEFI
version 2.7 specification. The combination of NVDIMM regions and
labels can lead to a wide variety of namespace layouts. Here we
support a simple subset of namespaces where each NVDIMM SPA range
is composed of a single region per member dimm.
Submitted by: D Scott Phillips <d.scott.phillips@intel.com>
Discussed with: kib
MFC after: 1 week
Sponsored by: Intel Corporation
Differential Revision: https://reviews.freebsd.org/D18736
Not all child devices of the NVDIMM root device represent DIMM devices
which are present in the system. The spec says (ACPI 6.2, sec 9.20.2):
For each NVDIMM present or intended to be supported by platform,
platform firmware also exposes an NVDIMM device ... under the
NVDIMM root device.
Present NVDIMM devices are found by walking all of the NFIT table's
SPA ranges, then walking the NVDIMM regions mentioned by those SPA
ranges.
A set of NFIT walking helper functions are introduced to avoid the
need to splat the enumeration logic across several disparate
callbacks.
Submitted by: D Scott Phillips <d.scott.phillips@intel.com>
Sponsored by: Intel Corporation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D18439
Driver enumerates NVDIMMs. Besides, for each found System Physical
Address (SPA) range, spaN geom provider is created, which allows
formatting and mounting the region as the normal volume. Also,
/dev/nvdimm_spaN node is created, which can be read/written/mapped by
userspace, the mapping is zero-copy.
No support for block access methods implemented, labels are not
parsed. No management interfaces are provided.
Tested by: Intel, NetApp
Sponsored by: The FreeBSD Foundation
Approved by: re (gjb)
MFC after: 2 weeks