Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Rename ARM_INTRNG and MIPS_INTRNG to INTRNG. This will help with machine
independent code that needs to know about INTRNG such as PCI drivers.

Obtained from: ABT Systems Ltd
Sponsored by: The FreeBSD Foundation

Generalize IPI support for ARM intrng and use it for interrupt
controller IPI provider.

New struct intr_ipi is defined which keeps all info about an IPI:
its name, counter, send and dispatch methods. Generic intr_ipi_setup(),
intr_ipi_send() and intr_ipi_dispatch() functions are implemented.

An IPI provider must implement two functions:
(1) an intr_ipi_send_t function which is able to send an IPI,
(2) a setup function which initializes itself for an IPI and
calls intr_ipi_setup() with appropriate arguments.

Differential Revision: https://reviews.freebsd.org/D5700

Almost all copies of platform_mp_init_secondary just called
intr_pic_init_secondary. Replace them with a direct call. On BCM2836
and ARMADA XP we need to add this function, but it can be empty.

Reviewed by: ian, imp
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D5460

Remove platform_mp_probe as it's almost identical on most ARM SoCs, and
slightly wrong on the others. We should just check if mp_ncpus is set to
more than one CPU as we may wish to run on a single core even when SMP is
available.

Reviewed by: ian
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D5458

Remove platform_ipi_send, it's an unneeded as all implementations are
identical.

Sponsored by: ABT Systems Ltd

ARM: Remove TLB IPI.
We don't support SMP on ARMv6. All ARMv7 multicore cpus already uses
hardware broadcast for TLB and cache operations.

[intrng] Migrate the intrng code from sys/arm/arm to sys/kern/subr_intr.c.

The ci20 port (by kan@) is going to reuse almost all of the intrng code
since the SoC in question looks suspiciously like someone took an ARM
SoC design and replaced the ARM core with a MIPS core.

* migrate out the code;
* rename ARM_ -> INTR_;
* rename arm_ -> intr_;
* move the interrupt flush routine from intr.c / intrng.c into
arm/machdep_intr.c - removing the code duplication and removing
the ARM specific bits from here.

Thanks to the Star Wars: The Force Awakens premiere line for allowing
me a couple hours of quiet time to finish the universe builds.

Tested:

* make universe

TODO:

* The structure definitions in subr_intr.c still includes machine/intr.h
which requires one duplicates all of the intrng definitions in
the platform code (which kan has done, and I think we don't have to.)

Instead I should break out the generic things (function declarations,
common intr structures, etc) into a separate header.

* Kan has requested I make the PIC based IPI stuff optional.

Import ARM_INTRNG, the "next generation" interrupt architecture for arm
and armv6 architecures. The primary enhancement over the old design is
support for hierarchical interrupt controllers (such as a gpio driver
which can receive interrupts from a root PIC and act as a PIC itself for
clients interested in handling a change of gpio pin state as an
interrupt). The new code also provides an infrastructure for mapping
interrupts described in metadata in the form of a "controller reference
plus interrupt number" tuple into the simple "0-n" flat numeric space
understood by rman and the bus resource mechanisms.

Use of the new code is enabled by setting the ARM_INTRNG option, and by
making a few simple changes to the platform's support code. In addition
each existing PIC driver needs changes to be ready for INTRNG; this commit
contains the changes for the arm/gic driver, which most armv6 SoCs use, but
it does not enable the new code yet on any platform.

This project has been many years in the making, starting as a GSoC project
by Jakub Klama (jceel@) in 2012. That didn't get committed right away and
the source base evolved out from under it to some degree. In 2014 I rebased
the diffs to then -current and did some enhancements in the area of mapping
interrupt numbers and storing associated fdt data, then the project went
cold again for a while. Eventually Svata Kraus took that work in progress
and did another big round of work on it, removing most of the remaining
rough edges. Finally I took that and made one more pass through it, mostly
disabling the "INTR_SOLO" feature for now, pending further design
discussions on how to most efficiently dispatch a pending interrupt through
more than one layer of PIC. The current code with the INTR_SOLO feature
disabled uses approximate 100 extra cpu cycles for each cascaded PIC the
interrupt has to be passed to, so what's left to do is about efficiency, not
correct operation.

Differential Revision: https://reviews.freebsd.org/D2047

Retire pmap_lazyfix(). This function only existed in the new armv6 pmap
because the i386 pmap on which the new armv6 pmap is based had it, and in
r281707 pmap_lazyfix() was removed from the i386 pmap.

Discussed with: kib
Submitted by: Michal Meloun (via Svatopluk Kraus)

New pmap code for armv6. Disabled by default, option ARM_NEW_PMAP enables it.

This is pretty much a complete rewrite based on the existing i386 code. The
patches have been circulating for a couple years and have been looked at by
plenty of people, but I'm not putting anybody on the hook as having reviewed
this in any formal sense except myself.

After this has gotten wider testing from the user community, ARM_NEW_PMAP
will become the default and various dregs of the old pmap code will be
removed.

Submitted by: Svatopluk Kraus <onwahe@gmail.com>,
Michal Meloun <meloun@miracle.cz>

Rename pic_ipi_get to pic_ipi_read for intrng.

There is no difference between IPI_STOP and IPI_STOP_HARD on ARM, so
map them both to the same interrupt number like other arches do.

Move the declaration for mpentry() into a header file instead of pasting
it into a bunch of different .c files. Remove declarations for the unused
mptramp() function from everywhere except AramadaXP (and I think it's
really not used there either, because the code that references it appears
to be insanely does-nothing in nature).

Explicitely include <machine/pcb.h>, so that we get the definition of
struct pcb.

Submitted by: Zbyszek Bodek <zbb@semihalf.com>
Pointy hat to: cognet

Define KDB_STOPPEDPCB, so that we can access the backtraces of threads running
on other cores.

Merging projects/armv6, part 1

Cummulative patch of changes that are not vendor-specific:
- ARMv6 and ARMv7 architecture support
- ARM SMP support
- VFP/Neon support
- ARM Generic Interrupt Controller driver
- Simplification of startup code for all platforms

Import FreeBSD/arm kernel bits.
It only supports sa1110 (on simics) right now, but xscale support should come
soon.
Some of the initial work has been provided by :
Stephane Potvin <sepotvin at videotron.ca>
Most of this comes from NetBSD.