Convert license tags to SPDX identifiers

This commit also converts our own copyright headers to directly use
SPDX, but leaves all other copyright header intact, only adding the
SPDX ident. As far as possible this commit also merges multiple
Data61 copyright statements/headers into one for consistency.

arm,SMP: Refactor irq_t structure for smp

Explicitly create a struct definition for irq_t on SMP Arm
configurations. This makes it a lot harder to mistakenly use the wrong
irq encoding when moving an irq between a cnode index and hardware irq
number / core. A couple areas where this was being handled incorrectly
was fixed as part of the refactor. When performing an ipi for masking
PPI interrupts, the idx encoding is used as it fits into a single word.

KernelIRQReporting: Change reserved IRQ reporting

Reserved IRQ reporting would print on every received reserved IRQ. This
feature is supposed to report spurious interrupts, yet most cases
reserved IRQs are not spurious. We change the printing to only print if
the reserved IRQ was unhandled. The intention is to allow more app
configurations to leave this feature enabled in development builds.

mcs: call updatetimestamp and commitTime once

This change refactors (and simplifies) the interactions with the
scheduler on the irq path. We don't call commitTime on this path,
as this call was redundant (we'll call it in the scheduler if we need
to). Move up the calls to checkBudget and updateTimestamp.

Avoid modifying the scheduler on the unlocked IPI path

mcs: add periodic scheduling

This commit adds periodic scheduling with sporadic servers.

mcs: tickless scheduler implementation

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.

[SMP] Abstracted IRQ indexing to handle PPIs

irq_t is now a "virtual" interrupt type that encapsulates the
information of the core in case of a private interrupt. There is a
couple of macros that need to be defined on the interrupt controller
level to translate between virtual and hardware IRQs.

RISC-V,PLIC: Cannot mask and unmask claimed IRQ

While masking and unmasking IRQs seems to work for some IRQ sources,
there are IRQ sources where masking an IRQ during a claim causes no
more IRQs to be raised after the IRQ is unmasked. This change
explicitly follows the claim->acknowledgement procedure that the
PLIC expects.

arm: remove plat/machine/timer.h

plat/machine/timer.h is unused on arm, so remove it and fix up the
includes.

style: set min-conditional-indent to 0

Given we use braces all the time conditional indents do not make code
cleaner.

style: consistently attach return type

Add attach-return-type to astyle

handleReservedIRQ now implemented on arch level except for pc99

Made declaration of handleReservedIRQ optional, refactored consequently

Inline resetTimer for all platforms

- for arm generic timer platforms, we remove resetTimer ->
resetGenericTimer indirection and simply include generic_timer.h
- this reduces boiler plate for platforms that share timer drivers, as
they simply include the one header
- there is far more timer code in the RT kernel, which motivates this
change

Print single IRQ error

`Arch_checkIRQ` already prints an error message in the case of x86. Printing the additional
error message is both unnecessary, confusing as the message makes no sense on x86. As the
error does make sense on ARM this commit moves the message to the arm `Arch_checkIRQ`

Check syscall irq argument before casting to irq_t

The syscall now rejects all invalid inputs, whereas previously it
silently truncated some invalid inputs.

SMP: Introduce ENABLE_SMP_SUPPORT

- Make it more readable and less confusing compared to the 'CONFIG_MAX_NUM_NODES > 1' check

SELFOUR-747: SMP/x86: generalize arch-independent IPI code

SELFOUR-160: Add missing userError messages

smp: fix bugs when stalling remote core

- Restart TCB from inside the lock if it is waiting for anything other than IRQ
- Only replace the TCB with idle thread if it is in ThreadState_RunningVM state

Also, this makes the design generic to be shared with arm.

SMP: Abstract architecture/platform independent parts of smp.h and ipi.h

This commit is a re-arrangement of SMP directory structure to make it
easier for other architectures/platforms (in general) and ARM (in
particular) to add SMP support.

* new include/smp directory to act as a centralised container of
"shared" architecture-independent SMP headers.
This makes it clearer what's needed for other architecture/platform to
support SMP.
* Each platform can define its own unique ipi.[h|c] that make sense,
since ipi implementation is SoC/platform dependent.

Explicitly cast usages of `irq_t` types

On some platforms `irq_t` is not defined as an `int` resulting in the `userError`
messages failing to type check. This adds an explicit cast

Debugging: Add userError messages for seL4_IRQControl_Get

implement layout of ipi interrupt handling

SELFOUR-632: implement cores non-architecture dependent structres

SELFOUR-607: inline remaining irq path functions

Trivial: move printfs in handleReservedIRQ up.

This wraps the printfs in CONFIG_IRQ_REPORTING
and reduces redundancy.

trivial: Add unlikely

trivial: Fix types when printing

The type of irq_t differs per platform, this commit just forces
a conversion to an int, which should be sufficient for a debug
message

SELFOUR-420: Avoid indexing intStateIRQTable with an invalid IRQ

x86: IOAPIC/MSI syscalls

Restructure the x86 interrupt handling to allow for a more flexible
method of using IOAPIC and MSI interrupts. The essence of this change
is to allow for the user to pick, for both IOAPIC and MSIs, which
CPU vector to use. Additionally there is future support, in the API,
for seL4 to eventually protect MSI interrupts with the vt-d interrupt
routing tables.

API behaviour for legacy systems using the PIC is preserved

Part of SELFOUR-281

Remove redundant IRQInterruptControl invocation, and replace with a mechanism to actually decode arch specific IRQ invocations

Part of SELFOUR-281

SELFOUR-114: remove duplication of seL4_MessageInfo_t, adjust naming to avoid cparser mangling

unsigned int -> word_t

Replaced "async endpoint" with "notification" in comments and error messages

SELFOUR-317: rename async endpoint to notification object, and other
fallout.

Introduce 'Notification Binding': a new feature which allows a tcb to be bound to a single asynchronous endpoint.

generate warnings for incorrect format strings for kprintf, bring stdint.h
inline for x86 and arm and fix some format strings as a consequence

Adjust -1 syntax for new Isabelle.

Weaken cap_async_cap cteDeleteOne assertions.

It's true that the interrupt node must contain async endpoint
caps, but we never proved the relevant invariant, and it doesn't
change much.

Ghost assertions for cteDeleteOne.

trivial: Fix string typos.

ioapic: trivial: style

ioapic: reverted setIRQState change

ioapic: refactored C code and first attempt at haskell spec

Support IOAPIC on ia32 and modify interrupt handling to support user level setting of modes

Recommit of arm_hyp branch on release snapshot

Release cleanup

Release snapshot