Add some the architected timer related infrastructure, and support timer
interrupt injection, which can happen as a resultof three possible
events:

- The virtual timer interrupt has fired while we were still
  executing the guest
- The timer interrupt hasn't fired, but it expired while we
  were doing the world switch
- A hrtimer we programmed earlier has fired
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Merge branch 'for-arm-soc/arch-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into kvm-arm/timer

It is now possible to select the VGIC configuration option.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add the init code for the hypervisor, the virtual machine, and
the virtual CPUs.

An interrupt handler is also wired to allow the VGIC maintenance
interrupts, used to deal with level triggered interrupts and LR
underflows.

A CPU hotplug notifier is registered to disable/enable the interrupt
as requested.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Enable the VGIC control interface to be save-restored on world switch.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Plug the interrupt injection code. Interrupts can now be generated
from user space.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

An interrupt may have been disabled after being made pending on the
CPU interface (the classic case is a timer running while we're
rebooting the guest - the interrupt would kick as soon as the CPU
interface gets enabled, with deadly consequences).

The solution is to examine already active LRs, and check the
interrupt is still enabled. If not, just retire it.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add VGIC virtual CPU interface code, picking pending interrupts
from the distributor and stashing them in the VGIC control interface
list registers.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add the GIC distributor emulation code. A number of the GIC features
are simply ignored as they are not required to boot a Linux guest.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

User space defines the model to emulate to a guest and should therefore
decide which addresses are used for both the virtual CPU interface
directly mapped in the guest physical address space and for the emulated
distributor interface, which is mapped in software by the in-kernel VGIC
support.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Wire the basic framework code for VGIC support and the initial in-kernel
MMIO support code for the VGIC, used for the distributor emulation.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When an interrupt occurs for the guest, it is sometimes necessary
to find out which vcpu was running at that point.

Keep track of which vcpu is being run in kvm_arch_vcpu_ioctl_run(),
and allow the data to be retrieved using either:
- kvm_arm_get_running_vcpu(): returns the vcpu running at this point
  on the current CPU. Can only be used in a non-preemptible context.
- kvm_arm_get_running_vcpus(): returns the per-CPU variable holding
  the running vcpus, usable for per-CPU interrupts.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

On ARM some bits are specific to the model being emulated for the guest and
user space needs a way to tell the kernel about those bits.  An example is mmio
device base addresses, where KVM must know the base address for a given device
to properly emulate mmio accesses within a certain address range or directly
map a device with virtualiation extensions into the guest address space.

We make this API ARM-specific as we haven't yet reached a consensus for a
generic API for all KVM architectures that will allow us to do something like
this.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The GIC include file being used by some of the KVM assembly code,
wrap the C definitions with a #ifdef __ASSEMBLY__ guard.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The GICH_* constants are defined by the GIC HW spec, and even though
they only be used by KVM to begin with, define them generically in gic.h.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add missing register map offsets for the distributor and rename
GIC_DIST_ACTIVE_BIT to GIC_DIST_ACTIVE_SET to be consistent.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChristoffer Dall <c.dall@virtualopensystems.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Merge branch 'for-will/arch-timer-unification' of git://linux-arm.org/linux-mr into for-arm-soc/arch-timers

Merge branch 'timers/for-arm' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into for-rmk/broadcast

Implement timer_broadcast for the arm architecture, allowing for the use
of clock_event_device_drivers decoupled from the timer tick broadcast
mechanism.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>

Currently, the ARM backend must maintain a redundant list of timers for
the purpose of centralising timer broadcast functionality. This prevents
sharing timer drivers across architectures.

This patch moves the pain of dealing with timer broadcasts to the core
clockevents tick broadcast code, which already maintains its own list
of timers.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>

Currently, the timer broadcast mechanism is defined by a function
pointer on struct clock_event_device. As the fundamental mechanism for
broadcast is architecture-specific, this means that clock_event_device
drivers cannot be shared across multiple architectures.

This patch adds an (optional) architecture-specific function for timer
tick broadcast, allowing drivers which may require broadcast
functionality to be shared across multiple architectures.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: nico@linaro.org
Cc: Will.Deacon@arm.com
Cc: Marc.Zyngier@arm.com
Cc: john.stultz@linaro.org
Link: http://lkml.kernel.org/r/1358183124-28461-3-git-send-email-mark.rutland@arm.comTested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Currently the broadcast mechanism used for timers is abstracted by a
function pointer on struct clock_event_device. As the fundamental
mechanism for broadcast is architecture-specific, this ties each
clock_event_device driver to a single architecture, even where the
driver is otherwise generic.

This patch adds a standard path for the receipt of timer broadcasts, so
drivers and/or architecture backends need not manage redundant lists of
timers for the purpose of routing broadcast timer ticks.

[tglx: Made the implementation depend on the config switch as well ]
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: nico@linaro.org
Cc: Will.Deacon@arm.com
Cc: Marc.Zyngier@arm.com
Cc: john.stultz@linaro.org
Link: http://lkml.kernel.org/r/1358183124-28461-2-git-send-email-mark.rutland@arm.comTested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

If we're booted in HYP mode, it is possible that we'll run some
kind of virtualized environment. In this case, it is a better to
switch to the physical timers, and leave the virtual timers to
guests.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@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>

The arch_timer driver supports a superset of the functionality of the
arm_generic driver, and is not tied to a particular arch.

This patch moves arm64 to use the arch_timer driver, gaining additional
functionality in doing so, and removes the (now unused) arm_generic
driver. Timer-related hooks specific to arm64 are moved into
arch/arm64/kernel/time.c.
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>

Currently arch_counter_get_cnt{p,v}ct can be speculated, allowing for
stale time values to be read. This could be problematic for the delay
loop and other sensitive functions, as the time delta could jump around
unexpectedly.

This patch adds isbs to arch_counter_get_cnt{p,v}ct, preventing this
possibility.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>

The core functionality of the arch_timer driver is not directly tied to
anything under arch/arm, and can be split out.

This patch factors out the core of the arch_timer driver, so it can be
shared with other architectures. A couple of functions are added so
that architecture-specific code can interact with the driver without
needing to touch its internals.

The ARM_ARCH_TIMER config variable is moved out to
drivers/clocksource/Kconfig, existing uses in arch/arm are replaced with
HAVE_ARM_ARCH_TIMER, which selects it.
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>

Several bits in CNTKCTL reset to 0, including PL0VTEN. For architectures
using the generic timer which wish to have a fast gettimeofday vDSO
implementation, these bits must be set to 1 by the kernel. For
architectures without a vDSO, it's best to leave the bits set to 0 for
now to ensure that if and when support is added, it's implemented sanely
architecture wide.

As the bootloader might set PL0VTEN to a value that doesn't correspond
to that which the kernel prefers, we must explicitly set it to the
architecture port's preferred value.

This patch adds arch_counter_set_user_access, which sets the PL0 access
permissions to that required by the architecture. For arch/arm, this
currently means disabling all userspace access.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>

Currently, the arch_timer driver is tied to the arm port, as it relies
on code in arch/arm/smp.c to setup and teardown timers as cores are
hotplugged on and off. The timer is registered through an arm-specific
registration mechanism, preventing sharing the driver with the arm64
port.

This patch moves the driver to using a cpu notifier instead, making it
easier to port.
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>

Without the isbs in arch_timer_get_cnt{p,v}ct the cpu may speculate
reads and return stale values. This could be bad for code sensitive to
changes in expected deltas between calls (e.g. the delay loop).

Without isbs in arch_timer_reg_write the processor may reorder
instructions around enabling/disabling of the timer or writing the
compare value, which we probably don't want.

This patch adds isbs to prevent those issues.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>

Currently the arch_timer register accessors are thrown together with
the main driver, preventing us from porting the driver to other
architectures.

This patch moves the register accessors into a header file, as with
the arm64 version. Constants required by the accessors are also moved.
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>

The CNTFRQ register is not duplicated for physical and virtual timers,
and accessing it as if it were is confusing.

Instead, use a separate accessor which doesn't take the access type
as a parameter.
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>

We're currently inconsistent with respect to our accesses to the
physical and virtual counters, mixing and matching the two.

This patch introduces and uses a function pointer for accessing the
correct counter based on whether we're using physical or virtual
interrupts. All current accesses to the counter accessors are redirected
through it.

When the driver is moved out to drivers/clocksource, there's the
possibility that code called before the timer code is initialised will
attempt to call arch_timer_read_counter (e.g. sched_clock for AArch64).
To avoid having to have to check whether the timer has been initialised
either in arch_timer_read_counter or one of it's callers, a default
implementation is assigned that simply returns 0.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>

To ensure the correct size of types, use u64 for the return value of
arch_timer_get_cnt{p,v}ct, and u32 for arch_timer_rate, matching the
size of the registers these values are taken from. While we're changing
them anyway, simplify the implementation of arch_timer_get_cnt{p,v}ct.
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>

This check is a holdover from the pre-devicetree days. As the timer
is not probed except by platforms which register it via devicetree,
it's not strictly necessary.
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>

When we get the device_node for the arch timer, it's refcount is
automatically incremented in of_find_matching_node, but it is
never decremented.

This patch decrements the refcount on the node after we're finished
using it.
Reported-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>

Pull x86 EFI fixes from Peter Anvin:
 "This is a collection of fixes for the EFI support.  The controversial
  bit here is a set of patches which bumps the boot protocol version as
  part of fixing some serious problems with the EFI handover protocol,
  used when booting under EFI using a bootloader as opposed to directly
  from EFI.  These changes should also make it a lot saner to support
  cross-mode 32/64-bit EFI booting in the future.  Getting these changes
  into 3.8 means we avoid presenting an inconsistent ABI to bootloaders.

  Other changes are display detection and fixing efivarfs."

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, efi: remove attribute check from setup_efi_pci
  x86, build: Dynamically find entry points in compressed startup code
  x86, efi: Fix PCI ROM handing in EFI boot stub, in 32-bit mode
  x86, efi: Fix 32-bit EFI handover protocol entry point
  x86, efi: Fix display detection in EFI boot stub
  x86, boot: Define the 2.12 bzImage boot protocol
  x86/boot: Fix minor fd leakage in tools/relocs.c
  x86, efi: Set runtime_version to the EFI spec revision
  x86, efi: fix 32-bit warnings in setup_efi_pci()
  efivarfs: Delete dentry from dcache in efivarfs_file_write()
  efivarfs: Never return ENOENT from firmware
  efi, x86: Pass a proper identity mapping in efi_call_phys_prelog
  efivarfs: Drop link count of the right inode

Pull x86 fixes from Peter Anvin:
 "This is a collection of miscellaneous fixes, the most important one is
  the fix for the Samsung laptop bricking issue (auto-blacklisting the
  samsung-laptop driver); the efi_enabled() changes you see below are
  prerequisites for that fix.

  The other issues fixed are booting on OLPC XO-1.5, an UV fix, NMI
  debugging, and requiring CAP_SYS_RAWIO for MSR references, just as
  with I/O port references."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  samsung-laptop: Disable on EFI hardware
  efi: Make 'efi_enabled' a function to query EFI facilities
  smp: Fix SMP function call empty cpu mask race
  x86/msr: Add capabilities check
  x86/dma-debug: Bump PREALLOC_DMA_DEBUG_ENTRIES
  x86/olpc: Fix olpc-xo1-sci.c build errors
  arch/x86/platform/uv: Fix incorrect tlb flush all issue
  x86-64: Fix unwind annotations in recent NMI changes
  x86-32: Start out cr0 clean, disable paging before modifying cr3/4

Pull console lockdep checking revert from Dave Airlie.

The lockdep splat this showed was interesting, but it's very very old,
and we won't be fixing it until 3.9.  In the meantime, undo the lockdep
annotation so that we don't generate the (known) console lockdep issue,
and then possibly hide any potential other (unknown) lockdep problems
that got disabled by the first one that triggered.

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  Revert "console: implement lockdep support for console_lock"