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

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

Simplify swi for bus_dma.

When a DMA request using bounce pages completes, a swi is triggered to
schedule pending DMA requests using the just-freed bounce pages. For
a long time this bus_dma swi has been tied to a "virtual memory" swi
(swi_vm). However, all of the swi_vm implementations are the same and
consist of checking a flag (busdma_swi_pending) which is always true
and if set calling busdma_swi. I suspect this dates back to the
pre-SMPng days and that the intention was for swi_vm to serve as a
mux. However, in the current scheme there's no need for the mux.

Instead, remove swi_vm and vm_ih. Each bus_dma implementation that
uses bounce pages is responsible for creating its own swi (busdma_ih)
which it now schedules directly. This swi invokes busdma_swi directly
removing the need for busdma_swi_pending.

One consequence is that the swi now works on RISC-V which had previously
failed to invoke busdma_swi from swi_vm.

Reviewed by: imp, kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D33447

minidump: Parameterize minidumpsys()

The minidump code is written assuming that certain global state will not
change, and rightly so, since it executes from a kernel debugger
context. In order to support taking minidumps of a live system, we
should allow copies of relevant global state that is likely to change to
be passed as parameters to the minidumpsys() function.

This patch does the work of parameterizing this function, by adding a
struct minidumpstate argument. For now, this struct allows for copies of
the kernel message buffer, and the bitset that tracks which pages should
be dumped (vm_page_dump). Follow-up changes will actually make use of
these arguments.

Notably, dump_avail[] does not need a snapshot, since it is not expected
to change after system initialization.

The existing minidumpsys() definitions are renamed, and a thin MI
wrapper is added to kern_dump.c, which handles the construction of
the state struct. Thus, calling minidumpsys() remains as simple as
before.

Reviewed by: kib, markj, jhb
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D31989

arm: Garbage collect _arm_memcpy/_arm_bzero.

Remove any attempt to use _arm_memcpy and _arm_bzero. It was used by some
xscale platforms to provide functions to use the DMA engine for big
zeroing/copying work, but those platforms are long gone, and it's unlikely
anything else will use those.

Remove remaining fragments of code for older already ceased ARM versions.

Move vm_page_dump bitset array definition to MI code

These definitions were repeated by all architectures, with small
variations. Consolidate the common definitons in machine
independent code and use bitset(9) macros for manipulation. Many
opportunities for deduplication remain in the machine dependent
minidump logic. The only intended functional change is increasing
the bit index type to vm_pindex_t, allowing the indexing of pages
with address of 8 TiB and greater.

Reviewed by: kib, markj
Approved by: scottl (implicit)
MFC after: 1 week
Sponsored by: Ampere Computing, Inc.
Differential Revision: https://reviews.freebsd.org/D26129

Convert arm's physmem interface to MI code

The arm_physmem interface found in arm's MD code provides a convenient
set of routines for adding/excluding physical memory regions and
initializing important kernel globals such as Maxmem, realmem,
phys_avail[], and dump_avail[]. It is especially convenient for FDT
systems, since we can use FDT parsing functions and pass the result
directly to one of these physmem routines. This interface is already in
use on arm and arm64, and can be used to simplify this early
initialization on RISC-V as well.

This requires only a couple trivial changes:
- Move arm_physmem_kernel_addr to arm/machdep.c. It is unused on arm64,
and manipulated entirely in arm MD code.
- Convert arm32_btop/arm64_btop to atop. This is equivalently defined
on all architectures.
- Drop the "arm" prefix.

Reviewed by: manu, emaste ("looks reasonable")
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D24153

Revert r336773: it removed too much.

r336773 removed all things xscale. However, some things xscale are
really armv5. Revert that entirely. A more modest removal will follow.

Noticed by: andrew@

Remove xscale support

The OLD XSCALE stuff hasn't been useful in a while. The original
committer (cognet@) was the only one that had boards for it. He's
blessed this removal. Newer XSCALE (GUMSTIX) is for hardware that's
quite old. After discussion on arm@, it was clear there was no support
for keeping it.

Differential Review: https://reviews.freebsd.org/D16313

sys: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

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.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Fullify implementation of AT_HWCAP and AT_HWCAP2 for ARMv6,7.
This makes elf_aux_info(3) useable for ARM ports.

MFC after: 1 month

Add AT_HWCAP flags for VFP settings for FreeBSD/arm.

These flags match the meaning and value of flags in Linux, though
Linux has many more flags.

Reviewed by: stevek, Michal Meloun <meloun-miracle-cz> (earlier version)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D12291

Implement userspace gettimeofday(2) with HPET timecounter.

Right now, userspace (fast) gettimeofday(2) on x86 only works for
RDTSC. For older machines, like Core2, where RDTSC is not C2/C3
invariant, and which fall to HPET hardware, this means that the call
has both the penalty of the syscall and of the uncached hw behind the
QPI or PCIe connection to the sought bridge. Nothing can me done
against the access latency, but the syscall overhead can be removed.
System already provides mappable /dev/hpetX devices, which gives
straight access to the HPET registers page.

Add yet another algorithm to the x86 'vdso' timehands. Libc is updated
to handle both RDTSC and HPET. For HPET, the index of the hpet device
to mmap is passed from kernel to userspace, index might be changed and
libc invalidates its mapping as needed.

Remove cpu_fill_vdso_timehands() KPI, instead require that
timecounters which can be used from userspace, to provide
tc_fill_vdso_timehands{,32}() methods. Merge i386 and amd64
libc/<arch>/sys/__vdso_gettc.c into one source file in the new
libc/x86/sys location. __vdso_gettc() internal interface is changed
to move timecounter algorithm detection into the MD code.

Measurements show that RDTSC even with the syscall overhead is faster
than userspace HPET access. But still, userspace HPET is three-four
times faster than syscall HPET on several Core2 and SandyBridge
machines.

Tested by: Howard Su <howard0su@gmail.com>
Sponsored by: The FreeBSD Foundation
MFC after: 1 month
Differential revision: https://reviews.freebsd.org/D7473

Add support for usermode (vdso-like) gettimeofday(2) and
clock_gettime(2) on ARMv7 and ARMv8 systems which have architectural
generic timer hardware. It is similar how the RDTSC timer is used in
userspace on x86.

Fix a permission problem where generic timer access from EL0 (or
userspace on v7) was not properly initialized on APs.

For ARMv7, mark the stack non-executable. The shared page is added for
all arms (including ARMv8 64bit), and the signal trampoline code is
moved to the page.

Reviewed by: andrew
Discussed with: emaste, mmel
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D4209

A follow-up to r288492. In fact, revert the mentioned commit for
pre-VFPv3 processors, since they do require software support code to
handle denormals. For VFPv3 and later, enable flush-to-zero if
hardware does not claim full denormals arithmetic support by VMVFR1_FZ
field in mvfr1 register.

The end result is that we do use correct fpu environment on Cortexes
with VFPv3, while ARM11 (e.g. rpi) is in non-compliant flush-to-zero
mode. At least CPUs without complete hardware implementation of
IEEE 754 do not cause unhandled floating point exception on underflow,
as it was before r288492.

Noted by: ian
Tested by: gjb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week

Declare Maxmem on arm. This should have been part of r277532.

Pass up the error status of minidumpsys() to its callers.

PR: 193761
Submitted by: Conrad Meyer <conrad.meyer@isilon.com>
Sponsored by: EMC / Isilon Storage Division

Remove all traces of support for ARM chips prior to the arm9 series. We
never actually ran on these chips (other than using SA1 support in an
emulator to do the early porting to FreeBSD long long ago). The clutter
and complexity of some of this code keeps getting in the way of other
maintenance, so it's time to go.

Add identification and necessary type checks for Krait CPU cores. Krait CPU is used in
Qualcomm Snapdragon S4 and Snapdragon 400/600/800 SoCs and has architectural
similarities to ARM Cortex-A15. As for development boards IFC6400 series embedded
boards from Inforce Computing uses Snapdragon S4 Pro/APQ8064.

Approved by: stas (mentor)

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

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

The FA526 belongs to the ARM9TDMI family

Show the cpu info for fa526

Submitted by: Yohanes Nugroho <yohanes at gmail dot com>

Promote the cpu_class local variable to global and expose it in md_var.h

Reviewed by: freebsd-arm

Support kernel crash mini dumps on ARM architecture.

Obtained from: Juniper Networks, Semihalf

- Import the HEAD csup code which is the basis for the cvsmode work.

- Add bounce pages for arm, largely based on the i386 implementation.
- Add a default parent dma tag, similar to what has been done for sparc64.
- Before invalidating the dcache in POSTREAD, save the bits which are in the
same cachelines than our buffers, but not part of it, and restore them after
the invalidation.

Add a new API to let platform-specific ports provide functions for big
copy/zeroing.

Declare sigcode and szsigcode.

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.