MFC r346312:

Only set up the interrupts that will actually be used in arm generic_timer.

The code previously set up interrupt handlers for all the interrupt
resources available, including for timers that are not in use. That could
lead to interrupt storms. For example, if boot firmware enabled the virtual
timer but the kernel is using the physical timer, it could get flooded with
interrupts on the virtual timer which it cannot shut off. By only setting
up an interrupt handler for the hardware that will actually be used, any
interrupts from other timer units will remain masked in the interrupt
controller.

Differential Revision: https://reviews.freebsd.org/D19871

Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

MFC r306658: Clear GT_CTRL_ENABLE to stop the timer.

MFC r304285:
Implement userspace gettimeofday(2) with HPET timecounter.

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

Allow arm generic_timer code to be included even if not present in the
SoC.

Reviewed by: andrew
Approved by: cognet (mentor)
Differential Revision: https://reviews.freebsd.org/D6372

The virtual timer is optional on ARM64. Properly handle that condition. [1]
In case we do not have an interrupt assignment for the virtual timer,
force the physical timer.
Also skip resource allocation for any timer we do not have an interrupt
assignment for.

In collaboration with: andrew
Submitted by: br ([1] from his gem5 arm64 work)
Sponsored by: DARPA/AFRL
Reviewed by: andrew
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D6203

The ARM generic timer keeps ticking even if disabled or it expired.
In case of updating it with a very low value it might expire again
after writing the tval but before updating ctrl. In that case we do
lose the status bit saying that the timer expired and we will consequently
not get an interrupt for it, leaving the timer in a "dead" state.

In order to solve this increase the minimum period with what the timer
can be loaded to something higher.

Found & analysed with: gem5
Debugged with: andrew
Sponsored by: DARPA/AFRL
Reviewed by: andrew
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D6202

Add a MULTIDELAY option to allow the ARM kernel to have multiple DELAY
implementations. Early in the boot the kernel will use an approximate,
however after the timer has been probed it will switch to a more accurate
implementation.

Reviewed by: manu
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D5762

Mark the unused period argument __unused.

Reviewed by: andrew
MFC after: 2 weeks
Sponsored by: DARPA/AFRL

Set sc->clkfreq removed in r295470

Reported by: Jared McNeill <jmcneill@invisible.ca>
Pointy-hat to: andrew

Use OF_getencprop to read a property, it already handles the endian
conversion so we don't need to pass the data through fdt32_to_cpu.

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

Add basic support for ACPI. It splits out the nexus driver to two new
drivers, one for fdt, one for acpi. It then uses this to decide if it will
use fdt or acpi.

The GICv2 (interrupt controller) and Generic Timer drivers have been
updated to handle both cases.

As this is early code we still need FDT to find the kernel console, and
some parts are still missing, including PCI support.

Differential Revision: https://reviews.freebsd.org/D2463
Reviewed by: jhb, jkim, emaste
Obtained from: ABT Systems Ltd
Relnotes: Yes
Sponsored by: The FreeBSD Foundation

Update the comment on what CPUs this driver supports.

Add support for arm64 to the existing arm generic timer driver:
- Add macros to handle the differences in accessing these registers on arm
and arm64.
- Use the fdt data to detect if we are on an ARMv7 or ARMv8.
- Use the virtual timer by default on arm64, we may not have access to
the physical timer.

Differential Revision: https://reviews.freebsd.org/D2208
Reviewed by: emaste
Sponsored by: The FreeBSD Foundation

Stop including machine/fdt.h, it's not needed.

Sponsored by: The FreeBSD Foundation

We may not be using gcc to compile this.

Sponsored by: The FreeBSD Foundation

Add the generic timer registers to sysreg.h and cpu-v6.h, and use the
access functions in the generic timer driver.

Differential Revision: https://reviews.freebsd.org/D2198
Sponsored by: The FreeBSD Foundation

Some device tree configurations place the generic timer under the root
of the tree and not under simplebus. Update the driver to handle this.

Submitted by: Julien Grall <julien.grall AT linaro.org>
MFC after: 1 week

We don't use the hypervisor interrupt, make it optional in the device tree.

Submitted by: Julien Grall <julien.grall AT linaro.org>
MFC after: 1 week

Allow us to use the virtual timer. It is currently disabled, but should
be usable as the default timer in place of the physical timer.

We are guaranteed to have access to the virtual timer, but when running
under a hypervisor may not have access to the physical.

Differential Revision: https://reviews.freebsd.org/D588

Attach arm generic interrupt and timer drivers in the middle of
BUS_PASS_INTERRUPT and BUS_PASS_TIMER, respectively.

- Setup both secure and non-secure timer IRQs.
We don't know our ARM security state, so one of them will operate.
- Don't set frequency, since it's unpossible in non-secure state.
Only rely on DTS clock-frequency value or get clock from timer.

Discussed with: ian, cognet

Replace many pasted identical definitions of cpu_initclocks() with a common
implementation in arm/machdep.c. Most arm platforms either don't need to
do anything, or just need to call the standard eventtimer init routines.
A generic implementation that does that is now provided via weak linkage.
Any platform that needs to do something different can provide a its own
implementation to override the generic one.

Follow r261352 by updating all drivers which are children of simplebus
to check the status property in their probe routines.

Simplebus used to only instantiate its children whose status="okay"
but that was improper behavior, fixed in r261352. Now that it doesn't
check anymore and probes all its children; the children all have to
do the check because really only the children know how to properly
interpret their status property strings.

Right now all existing drivers only understand "okay" versus something-
that's-not-okay, so they all use the new ofw_bus_status_okay() helper.

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.

o Make fields names short.
o Slim down reg fields comments.

Replace some spaces to tab.

Decrypt magic numbers - define names for fields of Generic Timer's CNTKCTL reg.

Submitted by: Ruslan Bukin <br@bsdpad.com>

Add ARM Generic Timer driver.

Submitted by: Ruslan Bukin <br@bsdpad.com>