sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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

arm: clean up empty lines in .c and .h files

Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718

Add support to the imx5/6 watchdog for the external reset signal. Also, if
the "power down" watchdog used by the ROM boot code is still active when the
regular watchdog is activated, turn off the power-down watchdog.

This adds support for the "fsl,ext-reset-output" FDT property. When
present, that property indicates that a chip reset is accomplished by
asserting the WDOG1_B external signal, which is supposed to trigger some
external component such as a PMIC to ready the hardware for reset (for
example, adjusting voltages from idle to full-power levels), and assert the
POR signal to SoC when ready. To guard against misconfiguation leading to a
non-rebootable system, the external reset signal is backstopped by code
that asserts a normal internal chip reset if nothing responds to the
external reset signal within one second.

Make the trivial imx_soc_family() function an inline in imx_machdep.h.

The imx_machdep.c file is on the fast path to non-existance and this would
be the only thing left in it after some watchdog changes are completed.

sys/arm: 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.

Handle imx6 erratum ERR004346... to reboot, clear the SRS bit twice within
the same cycle of the 32khz clock.

I've never actually noticed this error happening, but it's an easy fix.

Remove bus_dma_get_range and bus_dma_get_range_nb on armv6. We only need
this on a few earlier arm SoCs.

Reviewed by: manu (earlier version)
Sponsored by: ABT Systems Ltd

Move arm's devmap to some generic place, so it can be used
by other architectures.

Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D6091
Sponsored by: DARPA, AFRL
Sponsored by: HEIF5

Rename sysctl node hw.imx6 to hw.imx. Move its definition to imx_machdep.c
so that code shared between imx5 and imx6 can work with OIDs under that node.

Add last_reset_status (integer) and last_reset_reason (string) OIDs that
provide info about the last chip reset (power-on, software reset, watchdog
timeout).

Update the imx5/imx6 cpu_reset() implementation based on a new understanding
of the SRS (software reset) bit in the watchdog control register. Despite
what the manual seems to imply, this bit DOES trigger an immediate reset, as
opposed to simply flagging the type of reset as software-triggered.

Remove local devmap code and use the essentially identical common code
that got moved from imx_machdep.c to arm/devmap.c.

Call initarm_lastaddr() later in the init sequence, after establishing
static device mappings, rather than as the first of the initializations
that a platform can hook into. This allows a platform to allocate KVA
from the top of the address space downwards for things like static device
mapping, and return the final "last usable address" result after that and
other early init work is done.

Because some platforms were doing work in initarm_lastaddr() that needs to
be done early, add a new initarm_early_init() routine and move the early
init code to that routine on those platforms.

Rename platform_devmap_init() to initarm_devmap_init() to match all the
other init routines called from initarm() that are designed to be
implemented by platform code.

Add a comment block that explains when these routines are called and the
type of work expected to be done in each of them.

Move remaining code and data related to static device mapping into the
new devmap.[ch] files. Emphasize the MD nature of these things by using
the prefix arm_devmap_ on the function and type names (already a few of
these things found their way into MI code, hopefully it will be harder to
do by accident in the future).

Begin reducing code duplication in arm pmap.c and pmap-v6.c by factoring
out common code related to mapping device memory into a new devmap.c file.

Remove the growing duplication of code that used pmap_devmap_find_pa() and
then did some math with the returned results to generate a virtual address,
and likewise in reverse to get a physical address. Now there are a pair
of functions, arm_devmap_vtop() and arm_devmap_ptov(), to do that. The
bus_space_map() implementations are rewritten in terms of these.

Comments and style(9) only, no functional changes.

Remove #include <machine/frame.h> from all the arm code that doesn't
really need it. That would be almost everywhere it was included. Add
it in a couple files that really do need it and were previously getting
it by accident via another header.

Remove all #include <machine/pmap.h> from arm code. It's already
included by vm/pmap.h, which is a prerequisite for arm/machine/pmap.h
so there's no reason to ever include it directly.

Thanks to alc@ for pointing this out.

Maximize available kva space by doing static device mapping from the top
of the address space downwards, and then returning the lowest mapped
device address from initarm_lastaddr(). This adds over 500MB of kva
space compared to the old way of hardcoding the end address as 0xE0000000.

Also, pre-map most of the SoC's common memory-mapped devices using 1MB
section mappings so that all device access uses just a few TLB entries.
Graphics devices aren't mapped this way yet, but probably should be.

To provide this new functionality without pasting identical code into
multiple imxNN_machdep.c files, rework the imx machdep code so that
things common to the whole family of SoCs are in a new imx_machdep.c file.
The rewritten imxNN_machdep.c files contain just things specific to an
individual SoC.

Update copyright date.

Integrate Efika MX project back to home.

Sponsored by: The FreeBSD Foundation