sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

mvs: Remove unused devclass arguments to DRIVER_MODULE.

Make MAXPHYS tunable. Bump MAXPHYS to 1M.

Replace MAXPHYS by runtime variable maxphys. It is initialized from
MAXPHYS by default, but can be also adjusted with the tunable kern.maxphys.

Make b_pages[] array in struct buf flexible. Size b_pages[] for buffer
cache buffers exactly to atop(maxbcachebuf) (currently it is sized to
atop(MAXPHYS)), and b_pages[] for pbufs is sized to atop(maxphys) + 1.
The +1 for pbufs allow several pbuf consumers, among them vmapbuf(),
to use unaligned buffers still sized to maxphys, esp. when such
buffers come from userspace (*). Overall, we save significant amount
of otherwise wasted memory in b_pages[] for buffer cache buffers,
while bumping MAXPHYS to desired high value.

Eliminate all direct uses of the MAXPHYS constant in kernel and driver
sources, except a place which initialize maxphys. Some random (and
arguably weird) uses of MAXPHYS, e.g. in linuxolator, are converted
straight. Some drivers, which use MAXPHYS to size embeded structures,
get private MAXPHYS-like constant; their convertion is out of scope
for this work.

Changes to cam/, dev/ahci, dev/ata, dev/mpr, dev/mpt, dev/mvs,
dev/siis, where either submitted by, or based on changes by mav.

Suggested by: mav (*)
Reviewed by: imp, mav, imp, mckusick, scottl (intermediate versions)
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D27225

sys/dev: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

sys/dev: minor spelling fixes.

Most affect comments, very few have user-visible effects.

Fix SATA Gen3 speed constants.

MFC after: 1 week

Fix undefined behavior: (1 << 31) is not defined as 1 is an int and this
shifts into the sign bit. Instead use (1U << 31) which gets the
expected result.

This fix is not ideal as it assumes a 32 bit int, but does fix the issue
for most cases.

A similar change was made in OpenBSD.

Discussed with: -arch, rdivacky
Reviewed by: cperciva

- Limit r214102 workaround to only x86. On arm it causes more problems
then solves because of cache coherency issues. This fixes periodic error
messages on console and command timeouts.
- Patch SATA PHY configuration for 65nm SoCs to improve SNR same as
Linux does.

MFC after: 2 weeks

Adjust mvs(4) to handle interrupt cause reg depending on the actual number of
channels available

- current code treats bits 4:7 in 'SATAHC interrupt mask' and 'SATAHC
interrupt cause' as flags for SATA channels 2 and 3

- for embedded SATA controllers (SoC) these bits have been marked as reserved
in datasheets so far, but for some new and upcoming chips they are used for
purposes other than SATA

Submitted by: Lukasz Plachno
Reviewed by: mav
Obtained from: Semihalf
MFC after: 2 weeks

Fix some English grammar.

Refactor hard-reset implementation in mvs(4).

Instead of spinning in a tight loop for up to 15 seconds, polling for device
readiness while it spins up, return reset completion just after PHY reports
"connect well" or 100ms connection timeout. If device was found, use callout
for checking device readiness with 100ms period up to full 31 second timeout.

This fixes system freeze for 5-10 seconds on drives hot plug-in.

Implement automatic SCSI sense fetching for mvs(4).

Make few improvements/changes to ATAPI PIO support to pass most of scgcheck
(cdrtools) tests.

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

MFC r207536, r207696, r208183:
Import mvs(4) - Marvell 88SX50XX/88SX60XX/88SX70XX/SoC SATA controllers
driver for CAM ATA subsystem. This driver supports same hardware as
atamarvell, ataadaptec and atamvsata drivers from ata(4), but provides
many additional features, such as NCQ, PMP, etc.

Import mvs(4) - Marvell 88SX50XX/88SX60XX/88SX70XX/SoC SATA controllers
driver for CAM ATA subsystem. This driver supports same hardware as
atamarvell, ataadaptec and atamvsata drivers from ata(4), but provides
many additional features, such as NCQ, PMP, etc.