Peter Maydell suggested that we describe new devices / DTB nodes in the
kernel Documentation tree that we expose to arm "virt" guests in QEMU.

Although the kernel is not required to access the fw_cfg interface,
"Documentation/devicetree/bindings/arm" is probably the best central spot
to keep the fw_cfg description in.

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>

Pull staging driver updates from Greg KH:
 "Here's the big staging tree pull request for 3.19-rc1.

  We continued to delete more lines than were added, always a good
  thing, but not at a huge rate this release, only about 70k lines
  removed overall mostly from removing the horrid bcm driver.

  Lots of normal staging driver cleanups and fixes all over the place,
  well over a thousand of them, the shortlog shows all the horrid
  details.

  The "contentious" thing here is the movement of the Android binder
  code out of staging into the "real" part of the kernel.  This is code
  that has been stable for a few years now and is working as-is in the
  tens of millions of devices with no issues.  Yes, the code is horrid,
  and the userspace api leaves a lot to be desired, but it's not going
  to change due to legacy issues that we have no control over.  Because
  so many devices and companies rely on this, and the code is stable,
  might as well promote it out of staging.

  This was all discussed at the Linux Plumbers conference, and everyone
  participating agreed that this was the best way forward.

  There is work happening to replace the binder code with something new
  that is happening right now, but I don't expect to see the results of
  that work for another year at the earliest.  If that ever happens, and
  Android switches over to it, I'll gladly remove this version.

  As for maintainers, I'll be glad to maintain this code, I've been
  doing it for the past few years with no problems.  I'll send a
  MAINTAINERS entry for it before 3.19-final is out, still need to talk
  to the Google developers about if they are willing to help with it or
  not, last I checked they were, which was good.

  All of these patches have been in linux-next for a while with no
  reported issues"

* tag 'staging-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1382 commits)
  Staging: slicoss: Fix long line issues in slicoss.c
  staging: rtl8712: remove unnecessary else after return
  staging: comedi: change some printk calls to pr_err
  staging: rtl8723au: hal: Removed the extra semicolon
  lustre: Deletion of unnecessary checks before three function calls
  staging: lustre: fix sparse warnings: static function declaration
  staging: lustre: fixed sparse warnings related to static declarations
  staging: unisys: remove duplicate header
  staging: unisys: remove unneeded structure
  staging: ft1000 : replace __attribute ((__packed__) with __packed
  drivers: staging: rtl8192e: Include "asm/unaligned.h" instead of "access_ok.h" in "rtl819x_BAProc.c"
  Drivers:staging:rtl8192e: Fixed checkpatch warning
  Drivers:staging:clocking-wizard: Added a newline
  staging: clocking-wizard: check for a valid clk_name pointer
  staging: rtl8723au: Hal_InitPGData() avoid unnecessary typecasts
  staging: rtl8723au: _DisableAnalog(): Avoid zero-init variables unnecessarily
  staging: rtl8723au: Remove unnecessary wrapper _ResetDigitalProcedure1()
  staging: rtl8723au: _ResetDigitalProcedure1_92C() reduce code obfuscation
  staging: rtl8723au: Remove unnecessary wrapper _DisableRFAFEAndResetBB()
  staging: rtl8723au: _DisableRFAFEAndResetBB8192C(): Reduce code obfuscation
  ...

Pull irq domain ARM updates from Thomas Gleixner:
 "This set of changes make use of hierarchical irqdomains to provide:

   - MSI/ITS support for GICv3
   - MSI support for GICv2m
   - Interrupt polarity extender for GICv1

  Marc has come more cleanups for the existing extension hooks of GIC in
  the pipeline, but they are going to be 3.20 material"

* 'irq-irqdomain-arm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  irqchip: gicv3-its: Fix ITT allocation
  irqchip: gicv3-its: Move some alloc/free code to activate/deactivate
  irqchip: gicv3-its: Fix domain free in multi-MSI case
  irqchip: gic: Remove warning by including linux/irqdomain.h
  irqchip: gic-v2m: Add DT bindings for GICv2m
  irqchip: gic-v2m: Add support for ARM GICv2m MSI(-X) doorbell
  irqchip: mtk-sysirq: dt-bindings: Add bindings for mediatek sysirq
  irqchip: mtk-sysirq: Add sysirq interrupt polarity support
  irqchip: gic: Support hierarchy irq domain.
  irqchip: GICv3: Binding updates for ITS
  irqchip: GICv3: ITS: enable compilation of the ITS driver
  irqchip: GICv3: ITS: plug ITS init into main GICv3 code
  irqchip: GICv3: ITS: DT probing and initialization
  irqchip: GICv3: ITS: MSI support
  irqchip: GICv3: ITS: device allocation and configuration
  irqchip: GICv3: ITS: tables allocators
  irqchip: GICv3: ITS: LPI allocator
  irqchip: GICv3: ITS: irqchip implementation
  irqchip: GICv3: ITS command queue
  irqchip: GICv3: rework redistributor structure
  ...

Pull char/misc driver updates from Greg KH:
 "Here's the big char/misc driver update for 3.19-rc1

  Lots of little things all over the place in different drivers, and a
  new subsystem, "coresight" has been added.  Full details are in the
  shortlog"

* tag 'char-misc-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (73 commits)
  parport: parport_pc, do not remove parent devices early
  spmi: Remove shutdown/suspend/resume kernel-doc
  carma-fpga-program: drop videobuf dependency
  carma-fpga: drop videobuf dependency
  carma-fpga-program.c: fix compile errors
  i8k: Fix temperature bug handling in i8k_get_temp()
  cxl: Name interrupts in /proc/interrupt
  CXL: Return error to PSL if IRQ demultiplexing fails & print clearer warning
  coresight-replicator: remove .owner field for driver
  coresight: fixed comments in coresight.h
  coresight: fix typo in comment in coresight-priv.h
  coresight: bindings for coresight drivers
  coresight: Adding ABI documentation
  w1: support auto-load of w1_bq27000 module.
  w1: avoid potential u16 overflow
  cn: verify msg->len before making callback
  mei: export fw status registers through sysfs
  mei: read and print all six FW status registers
  mei: txe: add cherrytrail device id
  mei: kill cached host and me csr values
  ...

Pull ACPI and power management updates from Rafael Wysocki:
 "This time we have some more new material than we used to have during
  the last couple of development cycles.

  The most important part of it to me is the introduction of a unified
  interface for accessing device properties provided by platform
  firmware.  It works with Device Trees and ACPI in a uniform way and
  drivers using it need not worry about where the properties come from
  as long as the platform firmware (either DT or ACPI) makes them
  available.  It covers both devices and "bare" device node objects
  without struct device representation as that turns out to be necessary
  in some cases.  This has been in the works for quite a few months (and
  development cycles) and has been approved by all of the relevant
  maintainers.

  On top of that, some drivers are switched over to the new interface
  (at25, leds-gpio, gpio_keys_polled) and some additional changes are
  made to the core GPIO subsystem to allow device drivers to manipulate
  GPIOs in the "canonical" way on platforms that provide GPIO
  information in their ACPI tables, but don't assign names to GPIO lines
  (in which case the driver needs to do that on the basis of what it
  knows about the device in question).  That also has been approved by
  the GPIO core maintainers and the rfkill driver is now going to use
  it.

  Second is support for hardware P-states in the intel_pstate driver.
  It uses CPUID to detect whether or not the feature is supported by the
  processor in which case it will be enabled by default.  However, it
  can be disabled entirely from the kernel command line if necessary.

  Next is support for a platform firmware interface based on ACPI
  operation regions used by the PMIC (Power Management Integrated
  Circuit) chips on the Intel Baytrail-T and Baytrail-T-CR platforms.
  That interface is used for manipulating power resources and for
  thermal management: sensor temperature reporting, trip point setting
  and so on.

  Also the ACPI core is now going to support the _DEP configuration
  information in a limited way.  Basically, _DEP it supposed to reflect
  off-the-hierarchy dependencies between devices which may be very
  indirect, like when AML for one device accesses locations in an
  operation region handled by another device's driver (usually, the
  device depended on this way is a serial bus or GPIO controller).  The
  support added this time is sufficient to make the ACPI battery driver
  work on Asus T100A, but it is general enough to be able to cover some
  other use cases in the future.

  Finally, we have a new cpufreq driver for the Loongson1B processor.

  In addition to the above, there are fixes and cleanups all over the
  place as usual and a traditional ACPICA update to a recent upstream
  release.

  As far as the fixes go, the ACPI LPSS (Low-power Subsystem) driver for
  Intel platforms should be able to handle power management of the DMA
  engine correctly, the cpufreq-dt driver should interact with the
  thermal subsystem in a better way and the ACPI backlight driver should
  handle some more corner cases, among other things.

  On top of the ACPICA update there are fixes for race conditions in the
  ACPICA's interrupt handling code which might lead to some random and
  strange looking failures on some systems.

  In the cleanups department the most visible part is the series of
  commits targeted at getting rid of the CONFIG_PM_RUNTIME configuration
  option.  That was triggered by a discussion regarding the generic
  power domains code during which we realized that trying to support
  certain combinations of PM config options was painful and not really
  worth it, because nobody would use them in production anyway.  For
  this reason, we decided to make CONFIG_PM_SLEEP select
  CONFIG_PM_RUNTIME and that lead to the conclusion that the latter
  became redundant and CONFIG_PM could be used instead of it.  The
  material here makes that replacement in a major part of the tree, but
  there will be at least one more batch of that in the second part of
  the merge window.

  Specifics:

   - Support for retrieving device properties information from ACPI _DSD
     device configuration objects and a unified device properties
     interface for device drivers (and subsystems) on top of that.  As
     stated above, this works with Device Trees and ACPI and allows
     device drivers to be written in a platform firmware (DT or ACPI)
     agnostic way.  The at25, leds-gpio and gpio_keys_polled drivers are
     now going to use this new interface and the GPIO subsystem is
     additionally modified to allow device drivers to assign names to
     GPIO resources returned by ACPI _CRS objects (in case _DSD is not
     present or does not provide the expected data).  The changes in
     this set are mostly from Mika Westerberg, Rafael J Wysocki, Aaron
     Lu, and Darren Hart with some fixes from others (Fabio Estevam,
     Geert Uytterhoeven).

   - Support for Hardware Managed Performance States (HWP) as described
     in Volume 3, section 14.4, of the Intel SDM in the intel_pstate
     driver.  CPUID is used to detect whether or not the feature is
     supported by the processor.  If supported, it will be enabled
     automatically unless the intel_pstate=no_hwp switch is present in
     the kernel command line.  From Dirk Brandewie.

   - New Intel Broadwell-H ID for intel_pstate (Dirk Brandewie).

   - Support for firmware interface based on ACPI operation regions used
     by the PMIC chips on the Intel Baytrail-T and Baytrail-T-CR
     platforms for power resource control and thermal management (Aaron
     Lu).

   - Limited support for retrieving off-the-hierarchy dependencies
     between devices from ACPI _DEP device configuration objects and
     deferred probing support for the ACPI battery driver based on the
     _DEP information to make that driver work on Asus T100A (Lan
     Tianyu).

   - New cpufreq driver for the Loongson1B processor (Kelvin Cheung).

   - ACPICA update to upstream revision 20141107 which only affects
     tools (Bob Moore).

   - Fixes for race conditions in the ACPICA's interrupt handling code
     and in the ACPI code related to system suspend and resume (Lv Zheng
     and Rafael J Wysocki).

   - ACPI core fix for an RCU-related issue in the ioremap() regions
     management code that slowed down significantly after CPUs had been
     allowed to enter idle states even if they'd had RCU callbakcs
     queued and triggered some problems in certain proprietary graphics
     driver (and elsewhere).  The fix replaces synchronize_rcu() in that
     code with synchronize_rcu_expedited() which makes the issue go
     away.  From Konstantin Khlebnikov.

   - ACPI LPSS (Low-Power Subsystem) driver fix to handle power
     management of the DMA engine included into the LPSS correctly.  The
     problem is that the DMA engine doesn't have ACPI PM support of its
     own and it simply is turned off when the last LPSS device having
     ACPI PM support goes into D3cold.  To work around that, the PM
     domain used by the ACPI LPSS driver is redesigned so at least one
     device with ACPI PM support will be on as long as the DMA engine is
     in use.  From Andy Shevchenko.

   - ACPI backlight driver fix to avoid using it on "Win8-compatible"
     systems where it doesn't work and where it was used by default by
     mistake (Aaron Lu).

   - Assorted minor ACPI core fixes and cleanups from Tomasz Nowicki,
     Sudeep Holla, Huang Rui, Hanjun Guo, Fabian Frederick, and Ashwin
     Chaugule (mostly related to the upcoming ARM64 support).

   - Intel RAPL (Running Average Power Limit) power capping driver fixes
     and improvements including new processor IDs (Jacob Pan).

   - Generic power domains modification to power up domains after
     attaching devices to them to meet the expectations of device
     drivers and bus types assuming devices to be accessible at probe
     time (Ulf Hansson).

   - Preliminary support for controlling device clocks from the generic
     power domains core code and modifications of the ARM/shmobile
     platform to use that feature (Ulf Hansson).

   - Assorted minor fixes and cleanups of the generic power domains core
     code (Ulf Hansson, Geert Uytterhoeven).

   - Assorted minor fixes and cleanups of the device clocks control code
     in the PM core (Geert Uytterhoeven, Grygorii Strashko).

   - Consolidation of device power management Kconfig options by making
     CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and removing the latter
     which is now redundant (Rafael J Wysocki and Kevin Hilman).  That
     is the first batch of the changes needed for this purpose.

   - Core device runtime power management support code cleanup related
     to the execution of callbacks (Andrzej Hajda).

   - cpuidle ARM support improvements (Lorenzo Pieralisi).

   - cpuidle cleanup related to the CPUIDLE_FLAG_TIME_VALID flag and a
     new MAINTAINERS entry for ARM Exynos cpuidle (Daniel Lezcano and
     Bartlomiej Zolnierkiewicz).

   - New cpufreq driver callback (->ready) to be executed when the
     cpufreq core is ready to use a given policy object and cpufreq-dt
     driver modification to use that callback for cooling device
     registration (Viresh Kumar).

   - cpufreq core fixes and cleanups (Viresh Kumar, Vince Hsu, James
     Geboski, Tomeu Vizoso).

   - Assorted fixes and cleanups in the cpufreq-pcc, intel_pstate,
     cpufreq-dt, pxa2xx cpufreq drivers (Lenny Szubowicz, Ethan Zhao,
     Stefan Wahren, Petr Cvek).

   - OPP (Operating Performance Points) framework modification to allow
     OPPs to be removed too and update of a few cpufreq drivers
     (cpufreq-dt, exynos5440, imx6q, cpufreq) to remove OPPs (added
     during initialization) on driver removal (Viresh Kumar).

   - Hibernation core fixes and cleanups (Tina Ruchandani and Markus
     Elfring).

   - PM Kconfig fix related to CPU power management (Pankaj Dubey).

   - cpupower tool fix (Prarit Bhargava)"

* tag 'pm+acpi-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (120 commits)
  i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c
  dmaengine / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  tools: cpupower: fix return checks for sysfs_get_idlestate_count()
  drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  e1000e / igb / PM: Eliminate CONFIG_PM_RUNTIME
  MMC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  MFD / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  misc / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  media / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  input / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  leds: leds-gpio: Fix multiple instances registration without 'label' property
  iio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  hsi / OMAP / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  i2c-hid / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  drm / exynos / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  gpio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  hwrandom / exynos / PM: Use CONFIG_PM in #ifdef
  block / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM
  USB / PM: Drop CONFIG_PM_RUNTIME from the USB core
  PM: Merge the SET*_RUNTIME_PM_OPS() macros
  ...

Pull ARM SoC DT updates from Arnd Bergmann:
 "The DT branch adds a lot of new stuff for additional SoC and board
  support.  The branch is the largest one and contains 513 out of the
  total 972 non-merge arm-soc changesets for 3.19.

  Most of the changes are about enabling additional on-chip devices for
  existing machines, but there are also an unusual number of new SoC
  types being added this time:

   - AMLogic Meson8
   - ARM Realview in DT mode
   - Allwinner A80
   - Broadcom BCM47081
   - Broadcom Cygnus
   - Freescale LS1021A
   - Freescale Vybrid 500 series
   - Mediatek MT6592, MT8127, MT8135
   - STMicroelectronics STiH410
   - Samsung Exynos4415

  The level of support for the above differs widely, some are just stubs
  with nothing more than CPU, memory and a UART, but others are fairly
  complete.  As usual, these get extended over time.

  There are also many new boards getting added, this is the list of
  model strings that are showing up in new dts files:

   - ARM RealView PB1176
   - Altera SOCFPGA Arria 10
   - Asus RT-N18U (BCM47081)
   - Buffalo WZR-1750DHP (BCM4708)
   - Buffalo WZR-600DHP2 (BCM47081)
   - Cygnus Enterprise Phone (BCM911360_ENTPHN)
   - D-Link DIR-665
   - Google Spring
   - IGEP COM MODULE Rev. G (TI OMAP AM/DM37x)
   - IGEPv2 Rev. F (TI OMAP AM/DM37x)
   - LS1021A QDS Board
   - LS1021A TWR Board
   - LeMaker Banana Pi
   - MarsBoard RK3066
   - MediaTek MT8127 Moose Board
   - MediaTek MT8135 evaluation board
   - Mele M3
   - Merrii A80 Optimus Board
   - Netgear R6300 V2 (BCM4708)
   - Nomadik STN8815NHK
   - NovaTech OrionLXm
   - Olimex A20-OLinuXino-LIME2
   - Raspberry Pi Model B+
   - STiH410 B2120
   - Samsung Monk board
   - Samsung Rinato board
   - Synology DS213j
   - Synology DS414
   - TBS2910 Matrix ARM mini PC
   - TI AM5728 BeagleBoard-X15
   - Toradex Colibri VF50 on Colibri Evaluation Board
   - Zynq ZYBO Development Board

  Other notable changes include:

   - exynos: cleanup of existing dts files
   - mvebu: improved pinctrl support for Armada 370/XP
   - nomadik: restructuring dts files
   - omap: added CAN bus support
   - shmobile: added clock support for some SoCs
   - shmobile: added sound support for some SoCs
   - sirf: reset controller support
   - sunxi: continuing the relicensing under dual GPL/MIT
   - sunxi: lots of new on-chip device support
   - sunxi: working simplefb support (long awaited)
   - various: provide stdout-path property for earlycon"

* tag 'dt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (510 commits)
  ARM: dts: rk3288: add arm,cpu-registers-not-fw-configured
  Revert "ARM: dts: rockchip: temporarily disable smp on rk3288"
  ARM: BCM5301X: Add DT for Buffalo WZR-600DHP2
  ARM: BCM5301X: Add DT for Asus RT-N18U
  ARM: BCM5301X: Add DT for Buffalo WZR-1750DHP
  ARM: BCM5301X: Add DT for Netgear R6300 V2
  ARM: BCM5301X: Add buttons for Netgear R6250
  ARM: dts: rockchip: Add input voltage supply regulators in pmic for Marsboard
  ARM: BCM5301X: Add IRQs to Broadcom's bus-axi in DTS file
  arm: dts: zynq: Add Digilent ZYBO board
  arm: dts: zynq: Move crystal freq. to board level
  doc: dt: vendor-prefixes: Add Digilent Inc
  Documentation: devicetree: Fix Xilinx VDMA specification
  ARM: dts: rockchip: set FIFO size for SDMMC, SDIO and EMMC on rk3066 and rk3188
  ARM: dts: rockchip: add label property for leds on Radxa Rock
  ARM: BCM5301X: Add LEDs for Netgear R6250 V1
  ARM: BCM5301X: Add Broadcom's bus-axi to the DTS file
  ARM: dts: add sysreg phandle to i2c device nodes for exynos
  ARM: dts: Remove unused bootargs from exynos3250-rinato
  ARM: dts: add board dts file for Exynos3250-based Monk board
  ...

Pull ARM SoC driver updates from Arnd Bergmann:
 "These are changes for drivers that are intimately tied to some SoC and
  for some reason could not get merged through the respective subsystem
  maintainer tree.

  The largest single change here this time around is the Tegra
  iommu/memory controller driver, which gets updated to the new iommu DT
  binding.  More drivers like this are likely to follow for the
  following merge window, but we should be able to do those through the
  iommu maintainer.

  Other notable changes are:
   - reset controller drivers from the reset maintainer (socfpga, sti,
     berlin)
   - fixes for the keystone navigator driver merged last time
   - at91 rtc driver changes related to the at91 cleanups
   - ARM perf driver changes from Will Deacon
   - updates for the brcmstb_gisb driver"

* tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (53 commits)
  clocksource: arch_timer: Allow the device tree to specify uninitialized timer registers
  clocksource: arch_timer: Fix code to use physical timers when requested
  memory: Add NVIDIA Tegra memory controller support
  bus: brcmstb_gisb: Add register offset tables for older chips
  bus: brcmstb_gisb: Look up register offsets in a table
  bus: brcmstb_gisb: Introduce wrapper functions for MMIO accesses
  bus: brcmstb_gisb: Make the driver buildable on MIPS
  of: Add NVIDIA Tegra memory controller binding
  ARM: tegra: Move AHB Kconfig to drivers/amba
  amba: Add Kconfig file
  clk: tegra: Implement memory-controller clock
  serial: samsung: Fix serial config dependencies for exynos7
  bus: brcmstb_gisb: resolve section mismatch
  ARM: common: edma: edma_pm_resume may be unused
  ARM: common: edma: add suspend resume hook
  powerpc/iommu: Rename iommu_[un]map_sg functions
  rtc: at91sam9: add DT bindings documentation
  rtc: at91sam9: use clk API instead of relying on AT91_SLOW_CLOCK
  ARM: at91: add clk_lookup entry for RTT devices
  rtc: at91sam9: rework the Kconfig description
  ...

These are a pre-req to get rk3288 SMP to work with some firmwares, so merge
it in here as well as in next/drivers.

* clocksource/physical-timers:
  clocksource: arch_timer: Allow the device tree to specify uninitialized timer registers
  clocksource: arch_timer: Fix code to use physical timers when requested

Some 32-bit (ARMv7) systems are architected like this:

* The firmware doesn't know and doesn't care about hypervisor mode and
  we don't want to add the complexity of hypervisor there.

* The firmware isn't involved in SMP bringup or resume.

* The ARCH timer come up with an uninitialized offset (CNTVOFF)
  between the virtual and physical counters.  Each core gets a
  different random offset.

* The device boots in "Secure SVC" mode.

* Nothing has touched the reset value of CNTHCTL.PL1PCEN or
  CNTHCTL.PL1PCTEN (both default to 1 at reset)

On systems like the above, it doesn't make sense to use the virtual
counter.  There's nobody managing the offset and each time a core goes
down and comes back up it will get reinitialized to some other random
value.

This adds an optional property which can inform the kernel of this
situation, and firmware is free to remove the property if it is going
to initialize the CNTVOFF registers when each CPU comes out of reset.

Currently, the best course of action in this case is to use the
physical timer, which is why it is important that CNTHCTL hasn't been
changed from its reset value and it's a reasonable assumption given
that the firmware has never entered HYP mode.

Note that it's been said that on ARMv8 systems the firmware and
kernel really can't be architected as described above.  That means
using the physical timer like this really only makes sense for ARMv7
systems.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Sonny Rao <sonnyrao@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>