ARM: smp: Make SMP operations mandatory

Now that all SMP platforms have been converted to use struct
smp_operations, remove the "weak" attribute from the hooks
in smp.c, and make the functions static wherever possible.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
ARM: smp: remove wrapper functions

Remove some silly wrapper functions which aren't really required:
	platform_smp_prepare_cpus
	platform_secondary_init
	platform_cpu_die

This simplifies the code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
ARM: SoC: convert MSM to SMP operations

Convert MSM SMP platforms to use struct smp_operations to provide
their SMP and CPU hotplug operations.

[antypas@xda: Adapt to 8974/hammerhead]
[linflux@arcor.de: Minor cleanups]

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Cc: David Brown <davidb@codeaurora.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Revert "msm: mdss: Turn off backlight while power off"

Signed-off-by: Akhila Musunuri <makhila@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
sched: Remove get_online_cpus() usage

Remove get_online_cpus() usage from the scheduler; there's 4 sites that
use it:

 - sched_init_smp(); where its completely superfluous since we're in
   'early' boot and there simply cannot be any hotplugging.

 - sched_getaffinity(); we already take a raw spinlock to protect the
   task cpus_allowed mask, this disables preemption and therefore
   also stabilizes cpu_online_mask as that's modified using
   stop_machine. However switch to active mask for symmetry with
   sched_setaffinity()/set_cpus_allowed_ptr(). We guarantee active
   mask stability by inserting sync_rcu/sched() into _cpu_down.

 - sched_setaffinity(); we don't appear to need get_online_cpus()
   either, there's two sites where hotplug appears relevant:
    * cpuset_cpus_allowed(); for the !cpuset case we use possible_mask,
      for the cpuset case we hold task_lock, which is a spinlock and
      thus for mainline disables preemption (might cause pain on RT).
    * set_cpus_allowed_ptr(); Holds all scheduler locks and thus has
      preemption properly disabled; also it already deals with hotplug
      races explicitly where it releases them.

 - migrate_swap(); we can make stop_two_cpus() do the heavy lifting for
   us with a little trickery. By adding a sync_sched/rcu() after the
   CPU_DOWN_PREPARE notifier we can provide preempt/rcu guarantees for
   cpu_active_mask. Use these to validate that both our cpus are active
   when queueing the stop work before we queue the stop_machine works
   for take_cpu_down().

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[kaushalk@codeaurora.org: get_online_cpus has only 3 sites of usage in
 kernel/sched/core.c of msm-3.10 so migrate_swap changes are not
 applicable here. stop_two_cpus related change is not applicable to
 msm-3.10, so skip it.]
Signed-off-by: Kaushal Kumar <kaushalk@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
sched: Fix endless sync_sched/rcu() loop inside _cpu_down()

Commit bbe68f8267e290ef4c752b84833b6222bc2ce60b:

	sched: Remove get_online_cpus() usage

tries to do sync_sched/rcu() inside _cpu_down() but triggers:

	INFO: task swapper/0:1 blocked for more than 120 seconds.
	...
	[<ffffffff811263dc>] synchronize_rcu+0x2c/0x30
	[<ffffffff81d1bd82>] _cpu_down+0x2b2/0x340
	...

It was caused by that in the rcu boost case we rely on smpboot thread to
finish the rcu callback, which has already been parked before sync in here
and leads to the endless sync_sched/rcu().

This patch exchanges the sequence of smpboot_park_threads() and
sync_sched/rcu() to fix the bug.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kaushal Kumar <kaushalk@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
sched: Remove extra put_online_cpus() inside sched_setaffinity()

Commit bbe68f8267e290ef4c752b84833b6222bc2ce60b:

	sched: Remove get_online_cpus() usage

has left one extra put_online_cpus() inside sched_setaffinity(),
remove it to fix the WARN:

   ------------[ cut here ]------------
   WARNING: CPU: 0 PID: 3166 at kernel/cpu.c:84 put_online_cpus+0x43/0x70()
   ...
   [<ffffffff810c3fef>] put_online_cpus+0x43/0x70 [
   [<ffffffff810efd59>] sched_setaffinity+0x7d/0x1f9 [
   ...

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kaushal Kumar <kaushalk@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
crypto: msm: re-work qcrypto driver clk and bus management

This patch re-works bus scaling and clk management to respond to
the actual crypto engine usage. The driver suspend/resume are
integrated with overall driver clk and bus management.

Furthermore, two functions are added to the low level crypto driver. Low
level crypto driver is informed to save and restored hardware context if
necessary across PM suspend/resume.

Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
Signed-off-by: Zhen Kong <zkong@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
ARM: dts: msm: Update bus bandwidth votes for sdhci on 8974

Some versions of 8974 supports eMMC HS400 mode providing maximum
throughput of 400MB/s. Update the list of bus bandwidth votes to
make sure appropriate vote is placed in this mode.

Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
mmc: core: fix the issue with clock scaling in HS400 mode

Clock scaling feature would scale up/down the MMC interface clock
frequency based on the load on storage. During clock scale up in HS400
bus speed mode, SW is unncesserily doing the tuning even after HS400
switch is done. This change fixes this bug.

Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: Remove legacy driver for now

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: add new SMD TTY port

Add new port for exporting DATA4 (ATCoP) to userspace.

Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: add device tree support to smd_tty drivers

SMD TTY is configured using local tables that do not
allow customization on a per-target basis.

Add device tree support to configure SMD TTY devices.

Signed-off-by: Arun Kumar Neelakantam <aneela@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: fix missing open_timeout attribute

When systems are configured using device tree, the open timeout device
attribute is not created.

Move device attribute creation code to common device init function.

Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: replace wake lock with wakeup source

Wake locks have been deprecated.

Remove deprecated wake lock calls and replace with wakeup sources and
power-management calls.

Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: Add locking hierarchy

SMD TTY has several locks and it isn't clear what each lock manages.

Add a locking hierarchy and clarify locking scope.

Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: add separate port locking

Currently a single mutex is used to lock access to opening and closing
SMD TTY ports.  This lock is held while waiting for the open timeout to
expire which unnecessarily delays ports that could be opened
immediately.

Add an individual lock for each port to enable each port to be opened
and closed independently.

Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: fix section mismatch

A few methods specified with the __init flag can potentially be called
by methods that don't specify the __init flag. This poses a problem,
since the methods specified by the __init flag are freed after
initialization time.

Remove the __init flag from the methods that can be called after
initialization time.

Signed-off-by: Brent Hronik <bhronik@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
msm: smd_tty: unblock poll() in case of SSR

If an SSR is triggered, then read() and write() system calls are
unblocked by sending a TTY_BREAK to the TTY framework.  However, poll()
is not unblocked unless an error flag is set.

Set the TTY_OTHER_CLOSED bit to unblock poll().

Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
TTY: msm_smd_tty: Fix simultaneous open/close race condition

smd_tty_close currently has a variable that depends on a race
condition with tty_port_open. This causes a null-pointer dereference
when the same port is simultaneously being opened/closed.

Use data from a static array instead of the variable to eliminate
the race condition.

Signed-off-by: Steven Cahail <scahail@codeaurora.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>