Add a binding for the arm architected timer hardware's memory
mapped interface. The mmio timer hardware is made up of one base
frame and a collection of up to 8 timer frames, where each of the
8 timer frames can have either one or two views. A frame
typically maps to a privilege level (user/kernel, hypervisor,
secure). The first view has full access to the registers within a
frame, while the second view can be restricted to particular
registers within a frame. Each frame must support a physical
timer. It's optional for a frame to support a virtual timer.

Cc: devicetree-discuss@lists.ozlabs.org
Cc: Marc Zyngier <Marc.Zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robherring2@gmail.com>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: NMark Rutland <mark.rutland@arm.com>

Currently the documentation for the arch_timer devicetree binding only
lists "arm,armv7-timer".

Add "arm,armv8-timer" to the list of compatible strings.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>

Add runtime DT support and documentation for the Cortex A7/A15
architected timers.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>