Tickless timer drivers are yet to be implemented for

- allwinner
- apq8064
- am335x
- exynos4
- zynqmp
- imx8mm
- imx8mq

- use gpt, so we can have overflow and compare interrupts at the same
time (epit only allows compare)
- set the gpt to use the ipg_highfreq timer, as the standard ipg is too
low and breaks the timer calculations

Update the existing omap driver to implement the new tickless api.

Update the generic timer to implement the MCS kernels tickless timer
driver API and update all platforms that use the arm generic timers:

    - bcm2837
    - exynos5
    - hikey
    - imx7
    - odroidc2
    - tk1
    - tx1
    - tx2
    - zynq7000

Also move the generic timer constants to machine.h to avoid a circular
dependency.

- use in sabre (imx6) and zynq7000, the two platforms that were using
  the private timer.

This does not implement the timers for any platforms, but
provides the generic arm arch, and aarch32/aarch64 infrastructure for
tickless timer drivers.

Used for calculating constants for reciprocal division.

Add a tickless timer driver for x86. The driver defaults to using
TSC_DEADLINE mode, but falls back to the apic if that feature is not
available.

This changes the budget/remaining fields in scheduling contexts
to contain timer ticks, not number of abstract sel4ticks.

seL4_SchedControl_Configure now takes microseconds, not ticks.

This commit is plat-independant - the platform and arch specific
timer code follows in later commits.

This is the first part of the seL4 MCS. This commit:

    * adds a scheduling context object. Threads without scheduling
      context objects cannot be scheduled.
    * replaces tcbTimeSlice with the scheduling context object
    * adds seL4_SchedControl caps for each core
    * adds seL4_SchedControl_Configure which allows users to configure
      amount of ticks a scheduling context has, and set a core for the
      scheduling context.
    * adds seL4_SchedContext_Bind, Unbind and UnbindObject, which allows
      a tcb to be bound to a scheduling context.

This switches between master and mcs configurations.
This also adds a build system variable KernelPlatformSupportsMCS that
can be used to error on platforms that don't support MCS due to
unimplemented functionality.

In commit 24131333 ("trivial: disable
YAML loading warning"), an assumption was made that the version of pyaml
present was 5.1 or later; see https://msg.pyyaml.org/load .

Version the dependency.

For RISCVPageTableMap, decodeRISCVPageTableInvocation currently does not
check alignment of the user-provided vaddr. If it is not aligned, the
corresponding cap will end up with junk bits in its PTMappedAddress
field.

This used to be added automatically but now needs to be explicitly
listed.

userData is no longer needed to hold a reference to the IPC buffer. The
IPC buffer is now available as a thread local variable.

kernel_size has a default value of 0x1000 according to
hardware_schema.yml.

- remove add_build_rules() and replace with shorter inline impl.
- Remove nested for looping from Config.get_irqs() and .split_regions()
as we already know that a rule exists and have a reference to it via the
kernel device.
- Don't allow multiple rules for a single compatibility string. There
currently aren't multiple rules for a single string without any
motivating examples it is unclear whether this should be supported.

The kernel device IRQs and Frame mappings generated by this script will
only come from nodes specified in the seL4,kernel-devices property of
the chosen node.  Previously these devices were inferred by the script
but this led to false matching and didn't support easily overriding
which devices to match under different configurations or across
different platforms.

Explicitly specifying which devices from the device tree will be used in
the kernel makes it easier to check which devices the kernel is actually
using and makes it easier to change on a per platform or per
configuration basis.

- Device.regions() now just calculates memory regions without splitting
them into user and kernel groups.
- Config.split_regions() now calls Device.regions() and performs the
splitting if the device is a kernel device, otherwise returns the
original regions.
- Config.split_regions() is now only used in a context when dealing with
kernel devices, otherwise Device.regions() can be called to return only
informatioin extracted from the device tree.

- directly return IRQs from Device.get_interrupts(): Previously, these
IRQs were then mutated by Config.get_irqs() based on driver definitions
in hardware.yml. Inverting this order makes get_interrupts more general.
- Config.get_irqs() uses the Device it gets passed to call
get_interrupts() only when it needs to extract interrupts for a device.
- Use Config.get_irqs() for building kernel's IRQ list instead of
calling Device.get_interrupts() due to the new inversion.

Not used and it is unlikely that it will be needed in the near future.

Returns an array of interrupt affinities corresponding to an array of
interrupts for a Device.

- Use correct timer header file
- Use correct name for FVP target.

This name is case sensitive

Use the specific executable name "python2" to distinguish it from
"python" on distributions that install Python 3 as "python".

In Python 3, dict value iterators aren't deterministic between runs,
which causes nondeterministic definition output order. Some L4V proofs
are sensitive to this order.

Use sorted keys to guarantee order when iterating over values.

Update all scripts and build system to call python3, given python2's
upcoming doom. Use sys.maxsize instead of sys.maxint in one script
(maxint does not exist in python3).

Introduce a variable to hold a long expression to prevent the code
styler from line-wrapping the declare_platform() statement.  We want to
keep that on one line so the `griddle` tool (or humans) can easily
`grep` a list of supported platforms.  As of 2019-08-07, this platform
is the only one requiring this workaround.

This allows MCS and non-MCS versions of the kernel to go through the L4V
build process.

This dep is required by the elfloader for loading Arm and RISC-V
platforms.

This allows SMP support for the imx8m.

This allows SPIs to be routed to different cores.

This function enables ipis to be sent between cores.

Co-authored-by: Yanyan Shen <yanyan.shen@data61.csiro.au>

This commit updates the gic_v3 driver to translate virtual irqs to
hardware irq numbers, which enables PPI support for SMP.

This commit brings the gic_v3 is_sgi and is_ppi checks in line with
gicv2 making the code more consistent.

It also removes unneccessary conditionals in the checks, as is_sgi is
always called before is_ppi so the lower bounds checks are not required.

This removes a redundant constant to use one from the gic_common header.

In order to support gic_v3 SMP, move helpers from gic_v2.h to
gic_common.h

Move common definitions from gic_v2.h and gic_v3.h into gic_common.h

Co-authored-by: Yanyan Shen <yanyan.shen@data61.csiro.au>