ARM: l2c: vexpress ca9x4: move L2 cache initialisation earlier

It is beneficial to have the L2 cache up and running earlier in the
system boot.  Not only will this allow for simpler code when we come to
enable some features, but it also means that we get a more accurate
bogomips value for the udelay() loop.  Calibrating the loop with the
L2 cache off, and then running with the L2 cache on is not the best
idea.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: vexpress: convert to generic l2c OF initialisation

Remove the explicit call to l2x0_of_init(), converting to the generic
infrastructure instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: zynq: remove cache size override

The cache size should already be present in the L2 cache auxiliary
control register: it is part of the integration process to configure
the hardware IP.  Most platforms get this right, yet still many
cargo-cult program, and assume that they always need specifying to
the L2 cache code.  Remove them so we can find out which really need
this.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: zynq: convert to generic l2c OF initialisation

Remove the explicit call to l2x0_of_init(), converting to the generic
infrastructure instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: kill L2X0_AUX_CTRL_MASK before anyone else makes use of this

L2X0_AUX_CTRL_MASK is not useful for PL310s.  It would be better if
people thought about their value for this rather than cargo-cult
programming.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: remove old .set_debug method

We no longer need or require the .set_debug method; we handle everything
it used to do via the .write_sec method instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: print a warning with L2C-310 caches if the cache size is modified

As we have now removed all instances of the L2C-310 having its cache
size "modified" via platform/SoC code, discourage new cases showing
up by printing a warning.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: add warnings for stuff modifying aux_ctrl register values

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: l2c: trial at enabling some Cortex-A9 optimisations

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 8047/1: rwsem: use asm-generic rwsem implementation

asm-generic offers an atomic-add based rwsem implementation, which
can avoid the need for heavier, spinlock-based synchronisation on the
fast path.

This patch makes use of the optimised implementation for ARM CPUs.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 8062/1: Modify ldrt fixup handler to re-execute the userspace instruction

We will reach fixup handler when one thread(say cpu0) caused an undefined exception, while another thread(say cpu1) is unmmaping the page.

Fixup handler returns to the next userspace instruction which has caused the undef execption, rather than going to the same instruction.

ARM ARM says that after undefined exception, the PC will be pointing
to the next instruction. ie +4 offset in case of ARM and +2 in case of Thumb

And there is no correction offset passed to vector_stub in case of
undef exception.

File: arch/arm/kernel/entry-armv.S +1085
vector_stub     und, UND_MODE

During an undefined exception, in normal scenario(ie when ldrt
instruction does not cause an abort) after resorting the context in
VFP hardware, the PC is modified as show below before jumping to
ret_from_exception which is in r9.

File: arch/arm/vfp/vfphw.S +169
@ The context stored in the VFP hardware is up to date with this thread
vfp_hw_state_valid:
   tst     r1, #FPEXC_EX
   bne     process_exception     @ might as well handle the pending
                                 @ exception before retrying branch
                                 @ out before setting an FPEXC that
                                 @ stops us reading stuff
        VFPFMXR FPEXC, r1        @ Restore FPEXC last
        sub     r2, r2, #4       @ Retry current instruction - if Thumb
        str     r2, [sp, #S_PC]  @ mode it's two 16-bit instructions,
                                 @ else it's one 32-bit instruction, so
                                 @ always subtract 4 from the following
                                 @ instruction address.

But if ldrt results in an abort, we reach the fixup handler and return
to ret_from_execption without correcting the pc.

This patch modifes the fixup handler to re-execute the same instruction which caused undefined execption.

Signed-off-by: Vinayak Menon <vinayakm.list@gmail.com>
Signed-off-by: Arun KS <getarunks@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 8065/1: remove last use of CONFIG_CPU_ARM710

Support for ARM710 CPUs was removed in v3.5. Now remove the last code
depending on its Kconfig macro.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation

When configure kprobe events of ftrace with "stacktrace" option enabled
in arm, there is no stacktrace was recorded after the kprobe event was
triggered. The root cause is no save_stack_trace_regs() function implemented.

Implement the save_stack_trace_regs() function in arm, then ftrace will
call this architecture-related function to record the stacktrace into
ring buffer.

After this fix, stacktrace can be recorded, for example:

 # mount -t debugfs nodev /sys/kernel/debug
 # echo "p:netrx net_rx_action" >> /sys/kernel/debug/tracing/kprobe_events
 # echo 1 > /sys/kernel/debug/tracing/events/kprobes/netrx/enable
 # echo 1 > /sys/kernel/debug/tracing/options/stacktrace
 # echo 1 > /sys/kernel/debug/tracing/tracing_on
 # ping 127.0.0.1 -c 1
 # echo 0 > /sys/kernel/debug/tracing/tracing_on

 # cat /sys/kernel/debug/tracing/trace
 # tracer: nop
 #
 # entries-in-buffer/entries-written: 12/12   #P:1
 #
 #                              _-----=> irqs-off
 #                             / _----=> need-resched
 #                            | / _---=> hardirq/softirq
 #                            || / _--=> preempt-depth
 #                            ||| /     delay
 #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
 #              | |       |   ||||       |         |
             <------ missing some entries ---------------->
             ping-1200  [000] dNs1   667.603250: netrx: (net_rx_action+0x0/0x1f8)
             ping-1200  [000] dNs1   667.604738: <stack trace>
  => net_rx_action
  => do_softirq
  => local_bh_enable
  => ip_finish_output
  => ip_output
  => ip_local_out
  => ip_send_skb
  => ip_push_pending_frames
  => raw_sendmsg
  => inet_sendmsg
  => sock_sendmsg
  => SyS_sendto
  => ret_fast_syscall

Signed-off-by: Lin Yongting <linyongting@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Merge tag 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq into pm-devfreq

Pull devfreq updates for v3.16 from MyungJoo Ham.

 - Clean up with modern macro in the core and drivers.
 - Fix incorrect error returns
 - Remove dead CONFIG check.
 - Fix resource leak in a driver.

* tag 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mzx/devfreq:
  PM / devfreq: remove checks for CONFIG_EXYNOS_ASV
  PM / devfreq: exynos5: Use devm_devfreq_* function using device resource management
  PM / devfreq: exynos4: Use devm_devfreq_* function using device resource management
  PM / devfreq: Add devm_devfreq_{register,unregister}_opp_notfier function
  PM / devfreq: Add resource-managed function for devfreq device
  PM / devfreq: Fix devfreq_remove_device() to improve the sequence of resource free
  PM / devfreq: exynos: make more PPMU code common
  PM / devfreq: exynos5: introduce struct busfreq_ppmu_data
  PM / devfreq: exynos4: introduce struct busfreq_ppmu_data
  PM / devfreq: exynos4: use common PPMU code
  PM / devfreq: exynos5: Add CONFIG_PM_OPP dependency to fix probe fail
  PM / devfreq: exynos5: Use SIMPLE_DEV_PM_OPS macro
  PM / devfreq: exynos4: Add CONFIG_PM_OPP dependency to fix probe fail
  PM / devfreq: exynos4: Use SIMPLE_DEV_PM_OPS macro
  PM / devfreq: exynos4: Fix bug of resource leak and code clean on probe()
Revert "serial: imx: remove the DMA wait queue"

This reverts commit e2f2786606d49d3aae545c61c04757a64cf7e5f0.

Huang reports that this patch is broken and should be reverted.

Cc: Huang Shijie <b32955@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
KVM: s390: Add a generic function for translating guest addresses

This patch adds a function for translating logical guest addresses into
physical guest addresses without touching the memory at the given location.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
KVM: s390: Enable DAT support for TPROT handler

The TPROT instruction can be used to check the accessability of storage
for any kind of logical addresses. So far, our handler only supported
real addresses. This patch now also enables support for addresses that
have to be translated via DAT first. And while we're at it, change the
code to use the common KVM function gfn_to_hva_prot() to check for the
validity and writability of the memory page.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
KVM: s390: clean up interrupt injection in sigp code

We have all the logic to inject interrupts available in
kvm_s390_inject_vcpu(), so let's use it instead of
injecting irqs manually to the list in sigp code.

SIGP stop is special because we have to check the
action_flags before injecting the interrupt. As
the action_flags are not available in kvm_s390_inject_vcpu()
we leave the code for the stop order code untouched for now.

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
KVM: s390: check the given debug flags, not the set ones

This patch fixes a minor bug when updating the guest debug settings.
We should check the given debug flags, not the already set ones.
Doesn't do any harm but too many (for now unused) flags could be set internally
without error.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
KVM: s390: a VCPU is already started when delivering interrupts

This patch removes the start of a VCPU when delivering a RESTART interrupt.
Interrupt delivery is called from kvm_arch_vcpu_ioctl_run. So the VCPU is
already considered started - no need to call kvm_s390_vcpu_start. This function
will early exit anyway.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>