Running an OABI_COMPAT kernel on an SMP platform can lead to fun and
games with page aging.

If one CPU issues a swi instruction immediately before another CPU
decides to mkold the page containing the swi instruction, then we will
fault attempting to load the instruction during the vector_swi handler
in order to retrieve its immediate field. Since this fault is not
currently dealt with by our exception tables, this results in a panic:

  Unable to handle kernel paging request at virtual address 4020841c
  pgd = c490c000
  [4020841c] *pgd=84451831, *pte=bf05859d, *ppte=00000000
  Internal error: Oops: 17 [#1] PREEMPT SMP ARM
  Modules linked in: hid_sony(O)
  CPU: 1    Tainted: G        W  O  (3.4.0-perf-gf496dca-01162-gcbcc62b #1)
  PC is at vector_swi+0x28/0x88
  LR is at 0x40208420

This patch wraps all of the swi instruction loads with the USER macro
and provides a shared exception table entry which simply rewinds the
saved user PC and returns from the system call (without setting tbl, so
there's no worries with tracing or syscall restarting). Returning to
userspace will re-enter the page fault handler, from where we will
probably send SIGSEGV to the current task.
Reported-by: NWang, Yalin <yalin.wang@sonymobile.com>
Reviewed-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Commit 14318efb(ARM: 7587/1: implement optimized percpu variable access)
introduces arm's __my_cpu_offset to optimize percpu vaiable access,
which really works well on hackbench, but will cause __my_cpu_offset
to return garbage value before it is initialized in cpu_init() called
by setup_arch, so accessing percpu variable before setup_arch may cause
kernel hang. But generic __my_cpu_offset always returns zero before
percpu area is brought up, and won't hang kernel.

So the patch tries to clear __my_cpu_offset on boot CPU early
to avoid boot hang.

At least now percpu variable is accessed by lockdep before
setup_arch(), and enabling CONFIG_LOCK_STAT or CONFIG_DEBUG_LOCKDEP
can trigger kernel hang.
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Cc: stable@vger.kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Currently help message of /proc/sysrq-trigger highlights its
upper-case characters, like below:

      SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E)
      memory-full-oom-kill(F) kill-all-tasks(I) ...

this would confuse user trigger sysrq by upper-case character, which is
inconsistent with the real lower-case character registed key.

This inconsistent help message will also lead more confused when
26 upper-case letters put into use in future.

This patch fix arm etm sysrq key: "etm-buffer-dump(v)"
(This patch also add "-" to separate each sysrq key help word,
instead of spaces)
Signed-off-by: Nzhangwei(Jovi) <jovi.zhangwei@huawei.com>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slightly
different forms.  This patch introduces a generic function to print debug
information from show_regs() so that different archs print out the same
information and it's much easier to modify what's printed.

show_regs_print_info() prints out the same debug info as dump_stack()
does plus task and thread_info pointers.

* Archs which didn't print debug info now do.

  alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
  metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
  um, xtensa

* Already prints debug info.  Replaced with show_regs_print_info().
  The printed information is superset of what used to be there.

  arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86

* s390 is special in that it used to print arch-specific information
  along with generic debug info.  Heiko and Martin think that the
  arch-specific extra isn't worth keeping s390 specfic implementation.
  Converted to use the generic version.

Note that now all archs print the debug info before actual register
dumps.

An example BUG() dump follows.

 kernel BUG at /work/os/work/kernel/workqueue.c:4841!
 invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
 Modules linked in:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
 Hardware name: empty empty/S3992, BIOS 080011  10/26/2007
 task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
 RIP: 0010:[<ffffffff8234a07e>]  [<ffffffff8234a07e>] init_workqueues+0x4/0x6
 RSP: 0000:ffff88007c861ec8  EFLAGS: 00010246
 RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
 RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
 RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Stack:
  ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
  0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
  ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
 Call Trace:
  [<ffffffff81000312>] do_one_initcall+0x122/0x170
  [<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8
  [<ffffffff81c47760>] ? rest_init+0x140/0x140
  [<ffffffff81c4776e>] kernel_init+0xe/0xf0
  [<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0
  [<ffffffff81c47760>] ? rest_init+0x140/0x140
  ...

v2: Typo fix in x86-32.

v3: CPU number dropped from show_regs_print_info() as
    dump_stack_print_info() has been updated to print it.  s390
    specific implementation dropped as requested by s390 maintainers.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NJesper Nilsson <jesper.nilsson@axis.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>		[tile bits]
Acked-by: Richard Kuo <rkuo@codeaurora.org>		[hexagon bits]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Both dump_stack() and show_stack() are currently implemented by each
architecture.  show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack().  On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.

The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().

There's no reason to require archs to implement two separate but mostly
identical functions.  It leads to unnecessary subtle information.

This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin.  Blackfin's
dump_stack() does something wonky that I don't understand.

Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information.  This is used
in blackfin.

This patch brings the following behavior changes.

* On some archs, an extra level in backtrace for show_stack() could be
  printed.  This is because the top frame was determined in
  dump_stack() on those archs while generic dump_stack() can't do that
  reliably.  It can be compensated by inlining dump_stack() but not
  sure whether that'd be necessary.

* Most archs didn't use to print debug info on dump_stack().  They do
  now.

An example WARN dump follows.

 WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
 Hardware name: empty
 Modules linked in:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
  0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
  ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
  0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
 Call Trace:
  [<ffffffff81c614dc>] dump_stack+0x19/0x1b
  [<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0
  [<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20
  [<ffffffff8234a071>] init_workqueues+0x35/0x505
  ...

v2: CPU number added to the generic debug info as requested by s390
    folks and dropped the s390 specific dump_stack().  This loses %ksp
    from the debug message which the maintainers think isn't important
    enough to keep the s390-specific dump_stack() implementation.

    dump_stack_print_info() is moved to kernel/printk.c from
    lib/dump_stack.c.  Because linkage is per objecct file,
    dump_stack_print_info() living in the same lib file as generic
    dump_stack() means that archs which implement custom dump_stack()
    - at this point, only blackfin - can't use dump_stack_print_info()
    as that will bring in the generic version of dump_stack() too.  v1
    The v1 patch broke build on blackfin due to this issue.  The build
    breakage was reported by Fengguang Wu.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: NJesper Nilsson <jesper.nilsson@axis.com>
Acked-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>	[s390 bits]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Richard Kuo <rkuo@codeaurora.org>		[hexagon bits]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The early console implementations are the same all over the place.  Move
the print function to kernel/printk and get rid of the copies.

[akpm@linux-foundation.org: arch/mips/kernel/early_printk.c needs kernel.h for va_list]
[paul.gortmaker@windriver.com: sh4: make the bios early console support depend on EARLY_PRINTK]
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Reviewed-by: NIngo Molnar <mingo@kernel.org>
Tested-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since we now have default implementations for init_time and init_irq,
the init_machine callback is the only one that is not yet optional,
but since simple DT based platforms all have the same
of_platform_populate function call in there, we can consolidate them
as well, and then actually boot with a completely empty machine_desc.
Unofortunately we cannot just default to an empty init_machine: We
cannot call of_platform_populate before init_machine because that
does not work in case of auxdata, and we cannot call it after
init_machine either because the machine might need to run code
after adding the devices.

To take the final step, this adds support for booting without defining
any machine_desc whatsoever.

For the case that CONFIG_MULTIPLATFORM is enabled, it adds a
global machine descriptor that never matches any machine but is
used as a fallback if nothing else matches. We assume that without
CONFIG_MULTIPLATFORM, we only want to boot on the systems that the kernel
is built for, so we still retain the build-time warning for missing
machine descriptors and the run-time warning when the platform does not
match in that case.

In the case that we run on a multiplatform kernel and the machine
provides a fully populated device tree, we attempt to keep booting,
hoping that no machine specific callbacks are necessary.

Finally, this also removes the misguided "select ARCH_VEXPRESS" that
was only added to avoid a build error for allnoconfig kernels.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NOlof Johansson <olof@lixom.net>
Cc: "Russell King - ARM Linux" <linux@arm.linux.org.uk>
Cc: Rob Herring <robherring2@gmail.com>

Don't use create_proc_read_entry() as that is deprecated, but rather use
proc_create_data() and seq_file instead.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: Russell King <linux@arm.linux.org.uk>
cc: Kevin Hilman <khilman@deeprootsystems.com>
cc: Tony Lindgren <tony@atomide.com>
cc: linux-arm-kernel@lists.infradead.org
cc: linux-omap@vger.kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We use the vfp_host pointer to store the host VFP context, should
the guest start using VFP itself.

Actually, we can use this pointer in a more generic way to store
CPU speficic data, and arm64 is using it to dump the whole host
state before switching to the guest.

Simply rename the vfp_host field to host_cpu_context, and the
corresponding type to kvm_cpu_context_t. No change in functionnality.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <cdall@cs.columbia.edu>

We're about to move to an init procedure where we rely on the
fact that the init code fits in a single page. Make sure we
align the idmap text on a vector alignment, and that the code is
not bigger than a single page.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <cdall@cs.columbia.edu>

On resume from CPU power down any trace hooks enabled in cpu_init()
will get called before that function has done set_my_cpu_offset(),
so any use of per-cpu variables by trace hook code will cause bad
things to happen. Prevent this by marking the function notrace.

This fixes lockups/crashes seen when enabling function tracer on TC2
with the not yet mainlined cpuidle driver.
Signed-off-by: NJon Medhurst <tixy@linaro.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Commit 93dc6887 (ARM: 7684/1: errata: Workaround for Cortex-A15 erratum
798181 (TLBI/DSB operations)) introduces calls to smp_processor_id() and
smp_call_function_many() with preemption enabled. This patch disables
preemption and also optimises the smp_processor_id() call in
broadcast_tlb_mm_a15_erratum(). The broadcast_tlb_a15_erratum() function
is changed to use smp_call_function() which disables preemption.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Reported-by: NGeoff Levand <geoff@infradead.org>
Reported-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Instead of requiring the first man to be elected in advance (which
can be suboptimal in some situations), this patch uses a per-
cluster mutex to co-ordinate selection of the first man.

This should also make it more feasible to reuse this code path for
asynchronous cluster resume (as in CPUidle scenarios).

We must ensure that the vlock data doesn't share a cacheline with
anything else, or dirty cache eviction could corrupt it.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Signed-off-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>

This provides helper methods to coordinate between CPUs coming down
and CPUs going up, as well as documentation on the used algorithms,
so that cluster teardown and setup
operations are not done for a cluster simultaneously.

For use in the power_down() implementation:
  * __mcpm_cpu_going_down(unsigned int cluster, unsigned int cpu)
  * __mcpm_outbound_enter_critical(unsigned int cluster)
  * __mcpm_outbound_leave_critical(unsigned int cluster)
  * __mcpm_cpu_down(unsigned int cluster, unsigned int cpu)

The power_up_setup() helper should do platform-specific setup in
preparation for turning the CPU on, such as invalidating local caches
or entering coherency.  It must be assembler for now, since it must
run before the MMU can be switched on.  It is passed the affinity level
for which initialization should be performed.

Because the mcpm_sync_struct content is looked-up and modified
with the cache enabled or disabled depending on the code path, it is
crucial to always ensure proper cache maintenance to update main memory
right away.  The sync_cache_*() helpers are used to that end.

Also, in order to prevent a cached writer from interfering with an
adjacent non-cached writer, we ensure each state variable is located to
a separate cache line.

Thanks to Nicolas Pitre and Achin Gupta for the help with this
patch.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Signed-off-by: NNicolas Pitre <nico@linaro.org>
Reviewed-by: NWill Deacon <will.deacon@arm.com>

cyc_to_sched_clock() is called by sched_clock() and cyc_to_ns()
is called by cyc_to_sched_clock(). I suspect that some compilers
inline both of these functions into sched_clock() and so we've
been getting away without having a notrace marking. It seems that
my compiler isn't inlining cyc_to_sched_clock() though, so I'm
hitting a recursion bug when I enable the function graph tracer,
causing my system to crash. Marking these functions notrace fixes
it. Technically cyc_to_ns() doesn't need the notrace because it's
already marked inline, but let's just add it so that if we ever
remove inline from that function it doesn't blow up.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Flush the L1 cache for the CPU which is going down in cpu_die() so
that we don't end up with all platforms doing this.  This ensures
that any cache lines we own are pushed out before the cache becomes
inaccessible.

We may end up subsequently creating some dirty cache lines - for
example, with the complete() call, but this update must become
visible to other CPUs before __cpu_die() can proceed.  Subsequent
accesses from the platforms cpu_die() function should _not_ matter.

Also place a mb() after the complete() call to ensure that this is
visible to other CPUs.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Events may be created with attr->disabled == 1 and attr->enable_on_exec
== 1, which confuses the group validation code because events with the
PERF_EVENT_STATE_OFF are not considered candidates for scheduling, which
may lead to failure at group scheduling time.

This patch fixes the validation check for ARM, so that events in the
OFF state are still considered when enable_on_exec is true.

Cc: stable@vger.kernel.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Reported-by: NSudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We must not declare dbg_cpu_pm_nb as __cpuinitdata as we need it after
system initialization for Suspend and CPUIdle.

This was done in commit 9a6eb310 ("ARM: hw_breakpoint: Debug powerdown
support for self-hosted debug").

Cc: stable@vger.kernel.org
Cc: Dietmar Eggemann <Dietmar.Eggemann@arm.com>
Signed-off-by: NBastian Hecht <hechtb+renesas@gmail.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

tcm_init() call iotable_init() and it use early_alloc variants which
do memblock allocation. Directly using memblock allocation after
initializing bootmem should not permitted, because bootmem can't know
where are additinally reserved.
So move tcm_init() to a safe place before initalizing bootmem.

(On the U300)
Tested-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This converts arm and arm64 to use CLKSRC_OF DT based initialization for
the arch timer. A new function arch_timer_arch_init is added to allow for
arch specific setup.

This has a side effect of enabling sched_clock on omap5 and exynos5. There
should not be any reason not to use the arch timers for sched_clock.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>

Originally from a default machine descriptor patch from Arnd, pull out
just the default call to clocksource_of_init part. This is needed so that
platforms can simply remove .init_time calls as they are converted to use
clocksource_of_init.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

Only 32-bits of the arch timer were being used and wrapping was needlessly
being done in s/w. By using the full counter (56-64 bits), we don't need
to deal with wrapping and can simplify the implementation when using
arch timer.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

This converts sched_clock to simply a call to a function pointer in order
to allow overriding it. This will allow for use with 64-bit counters where
overflow handling is not needed.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

Allow multiple calls to setup_sched_clock and switch to the new counter
if it is higher frequency.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>

The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data.  Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Use the generic idle loop and replace enable/disable_hlt with the
respective core functions.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: NCc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Tested-by: Kevin Hilman <khilman@linaro.org> # OMAP
Link: http://lkml.kernel.org/r/20130321215233.826238797@linutronix.de

enable/disable_hlt() does not need to be exported and can be killed on
architectures which do not use it at all.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: NCc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Link: http://lkml.kernel.org/r/20130321215233.377959540@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

commit 91d1aa43 (context_tracking: New context tracking susbsystem)
generalized parts of the RCU userspace extended quiescent state into
the context tracking subsystem.  Context tracking is then used
to implement adaptive tickless (a.k.a extended nohz)

To support the new context tracking subsystem on ARM, the user/kernel
boundary transtions need to be instrumented.

For exceptions and IRQs in usermode, the existing usr_entry macro is
used to instrument the user->kernel transition.  For the return to
usermode path, the ret_to_user* path is instrumented.  Using the
usr_entry macro, this covers interrupts in userspace, data abort and
prefetch abort exceptions in userspace as well as undefined exceptions
in userspace (which is where FP emulation and VFP are handled.)

For syscalls, the slow return path is covered by instrumenting the
ret_to_user path.  In addition, the syscall entry point is
instrumented which covers the user->kernel transition for both fast
and slow syscalls, and an additional instrumentation point is added
for the fast syscall return path (ret_fast_syscall).

Cc: Mats Liljegren <mats.liljegren@enea.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The PCI specifications says that an I/O region must be aligned on a 4
KB boundary, and a memory region aligned on a 1 MB boundary.

However, the Marvell PCIe interfaces rely on address decoding windows
(which allow to associate a range of physical addresses with a given
device). For PCIe memory windows, those windows are defined with a 1
MB granularity (which matches the PCI specs), but PCIe I/O windows can
only be defined with a 64 KB granularity, so they have to be 64 KB
aligned. We therefore need to tell the PCI core about this special
alignement requirement.

The PCI core already calls pcibios_align_resource() in the ARM PCI
core, specifically for such purposes. So this patch extends the ARM
PCI core so that it calls a ->align_resource() hook registered by the
PCI driver, exactly like the existing ->map_irq() and ->swizzle()
hooks.

A particular PCI driver can register a align_resource() hook, and do
its own specific alignement, depending on the specific constraints of
the underlying hardware.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

All svc exit paths need IRQs off.  Rather than placing this before
every user of svc_exit, combine it into this macro.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The IRQ tracing exit path is much the same between all SVC mode
exits, so move this into the svc_exit macro.  Use a macro parameter
to identify the IRQ case, which is the only different case there is.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The contents of the asm_trace_hardirqs_on is already conditional on
CONFIG_TRACE_IRQFLAGS.  There's little point also making the use
of the macro conditional as well.  Get rid of these ifdefs to make
the code easier to read.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

CONFIG_LPAE doesn't exist: the correct option is CONFIG_ARM_LPAE, so fix
up the two typos under arch/arm/.

The fix to head.S is slightly scary, but this is just for setting up
an early io-mapping for the serial port when running on a big-endian,
LPAE system. Since these systems don't exist in the wild (at least, I
have no access to one outside of kvmtool, which doesn't provide a serial
port suitable for earlyprintk), then we can revisit the code later if it
causes any problems.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add unwind annotations to the ftrace assembly code so that the function
tracer's stacktracing options (func_stack_trace, etc.) work when
CONFIG_ARM_UNWIND is enabled.
Signed-off-by: NRabin Vincent <rabin@rab.in>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Commit 70264367 ("ARM: 7653/2: do not scale loops_per_jiffy when
using a constant delay clock") fixed a problem with our timer-based
delay loop, where loops_per_jiffy is scaled by cpufreq yet used directly
by the timer delay ops.

This patch fixes the problem in a more elegant way by keeping a private
ticks_per_jiffy field in the delay ops, independent of loops_per_jiffy
and therefore not subject to scaling. The loop-based delay continues to
use loops_per_jiffy directly, as it should.
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

On Cortex-A15 (r0p0..r3p2) the TLBI/DSB are not adequately shooting down
all use of the old entries. This patch implements the erratum workaround
which consists of:

1. Dummy TLBIMVAIS and DSB on the CPU doing the TLBI operation.
2. Send IPI to the CPUs that are running the same mm (and ASID) as the
   one being invalidated (or all the online CPUs for global pages).
3. CPU receiving the IPI executes a DMB and CLREX (part of the exception
   return code already).
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

More and more sub-architectures are using only the irqchip_init
function. Make the core code call this function if no init_irq field is
provided in the machine description to remove some boilerplate code.
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NOlof Johansson <olof@lixom.net>