The same workaround as ff999b8a
"ARM: OMAP4460: Workaround for ROM bug because of CA9 r2pX GIC ..."
need to be applied not only when system is booting, but when MPUSS hits
OSWR state through CPUIdle too. Without this WA the same issue is
reproduced now on boards PandaES and Tablet/Blaze with SOM OMAP4460
when CONFIG_CPU_IDLE is enabled.
After MPUSS has enterred OSWR and waken up:
- GIC distributor became disabled forever
- scheduling is not performed any more

Cc: Kevin Hilman <khilman@linaro.org>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reported-by: NTaras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NOlof Johansson <olof@lixom.net>

We call cpu_cluster_pm_enter for dev->cpu == 0 only, but
cpu_cluster_pm_exit called without that check.

Because of that unhandled page fault may happen:

[    3.803405] Unable to handle kernel paging request at virtual address 00002500
[    3.810974] pgd = c0004000
[    3.813812] [00002500] *pgd=00000000
[    3.817596] Internal error: Oops: 5 [#1] SMP ARM
[    3.822418] Modules linked in:
[    3.825653] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.11.0-rc6+ #21
[    3.832397] task: ed86ef40 ti: ed896000 task.ti: ed896000
[    3.838073] PC is at irq_notifier+0x234/0x25c
[    3.842651] LR is at irq_notifier+0x218/0x25c
[    3.847229] pc : [<c0029ed8>]    lr : [<c0029ebc>]    psr: 80000193
[    3.847229] sp : ed897ee8  ip : 00000005  fp : 00000001
[    3.859283] r10: c0b395f0  r9 : c0b30594  r8 : c0b8c2ac
[    3.864776] r7 : ffffffff  r6 : 00000000  r5 : 00000005  r4 : 00000000
[    3.871643] r3 : 00002500  r2 : 00000000  r1 : 00000005  r0 : 44302244
[    3.878479] Flags: Nzcv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
[    3.886260] Control: 10c5387d  Table: 8000404a  DAC: 00000015
[    3.892272] Process swapper/1 (pid: 0, stack limit = 0xed896240)
[    3.898590] Stack: (0xed897ee8 to 0xed898000)
[    3.903167] 7ee0:                   c0979c3a 00000001 ed897ef8 ed896000 c0014f7c 00000000
[    3.911743] 7f00: 00000005 00000000 ffffffff c0b8c2ac c0b395f0 c077c04c c0c94b48 c0b3953c
[    3.920318] 7f20: c0bcd928 00000002 c0b39524 c00cfad8 00000000 ffffffff 00000000 c00cfb10
[    3.928924] 7f40: c14e62c0 c002c1c8 c002c0ac c14e62c0 00000002 e251c37d 00000000 c0b39548
[    3.937499] 7f60: c0b395f0 c05a1bc4 e251c37d 00000000 00000005 c05a3870 edc90380 edc90380
[    3.946105] 7f80: edc90394 c14e62c0 c0b39548 00000002 c0784064 c05a3c78 c0b395e0 c14e62c0
[    3.954681] 7fa0: 00000002 c0b39548 c0bc9db8 00000000 00000001 c05a1dc0 ed896000 00000015
[    3.963287] 7fc0: c0bc9db8 ed896000 8000406a c0b30594 c0784064 c000e504 00000746 c007a528
[    3.971862] 7fe0: 00000001 0000001d 600001d3 c0bcc004 00000000 800086c4 ee0aa6a7 d2aabaa9
[    3.980499] [<c0029ed8>] (irq_notifier+0x234/0x25c) from [<c077c04c>] (notifier_call_chain+0x38/0x68)
[    3.990173] [<c077c04c>] (notifier_call_chain+0x38/0x68) from [<c00cfad8>] (cpu_pm_notify+0x20/0x38)
[    3.999786] [<c00cfad8>] (cpu_pm_notify+0x20/0x38) from [<c00cfb10>] (cpu_cluster_pm_exit+0x20/0x50)
[    4.009399] [<c00cfb10>] (cpu_cluster_pm_exit+0x20/0x50) from [<c002c1c8>] (omap_enter_idle_coupled+0x11c/0x14c)
[    4.020111] [<c002c1c8>] (omap_enter_idle_coupled+0x11c/0x14c) from [<c05a1bc4>] (cpuidle_enter_state+0x40/0xec)
[    4.030822] [<c05a1bc4>] (cpuidle_enter_state+0x40/0xec) from [<c05a3c78>] (cpuidle_enter_state_coupled+0x1f4/0x240)
[    4.041870] [<c05a3c78>] (cpuidle_enter_state_coupled+0x1f4/0x240) from [<c05a1dc0>] (cpuidle_idle_call+0x150/0x228)
[    4.052947] [<c05a1dc0>] (cpuidle_idle_call+0x150/0x228) from [<c000e504>] (arch_cpu_idle+0x8/0x38)
[    4.062499] [<c000e504>] (arch_cpu_idle+0x8/0x38) from [<c007a528>] (cpu_startup_entry+0x178/0x1e4)
[    4.071990] [<c007a528>] (cpu_startup_entry+0x178/0x1e4) from [<800086c4>] (0x800086c4)
[    4.080383] Code: e5922288 03a03b0a 13a03c25 e0823003 (e5932000)
[    4.086791] ---[ end trace d83954a84a6fa69e ]---

It is supposed that sar_base is initialized in irq_save_context, which
is called on CPU_CLUSTER_PM_ENTER notification. If this notification
has been missed and CPU_CLUSTER_PM_EXIT is received sar_base is NULL.

Fix it by calling CPU_CLUSTER_PM_{ENTER,EXIT} under the same condition.
Signed-off-by: NVladimir Murzin <murzin.v@gmail.com>
Acked-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: NKevin Hilman <khilman@linaro.org>
Tested-by: NKevin Hilman <khilman@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The en_core_tk_irqen flag is set in all the cpuidle driver which
means it is not necessary to specify this flag.

Remove the flag and the code related to it.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>  # for mach-omap2/*
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The OMAP5 idle driver can re-use most of OMAP4 CPUidle driver
implementation. Also the next derivative SOCs are going to re-use
the MPUSS so, same driver with minor updates can be re-used.

Prepare the code so that its easier to add CPUidle support for
OMAP5 devices.
Acked-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NKevin Hilman <khilman@linaro.org>

Current OMAP4 CPUIdle driver is using omap4_mpuss_read_prev_context_state()
to check whether the MPU cluster lost context or not before calling
cpu_cluster_pm_exit().  This was initially done an optimization for
corner cases, where if the cluster low power entry fails for some
reason, the cluster context restore gets skipped.  However, since
reading the previous context is expensive (involving slow accesses to
the PRCM), it's better to avoid it and simply check the target cluster
state instead.

Moving forward, OMAP CPUidle drivers needs to be moved to drivers/idle/*
once the PRM/CM code gets moved to drivers. This patch also reduces one
dependency with platform code for idle driver movement.
Acked-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
[khilman@linaro.org: minor changelog edits]
Signed-off-by: NKevin Hilman <khilman@linaro.org>

It is useful to know the CPU power state along with MPUSS power state
in a supported C-state. Since the data is available via sysfs, one can
avoid scrolling the source code for precise construction of C-state.
Reported-by: NNishanth Menon <nm@ti.com>
Acked-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NKevin Hilman <khilman@linaro.org>

If the CPUidle device registration fails for some reason, we should
unregister the driver on error path.

Fix the code accordingly. Also when at it, check of the driver registration
failure too.
Acked-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NKevin Hilman <khilman@linaro.org>

OMAP4 CPUidle driver registration call is under a loop which leads
to calling cpuidle_register_driver twice which is not intended.

Fix it by moving the driver registration outside the loop.
Reported-by: NNishanth Menon <nm@ti.com>
Acked-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NKevin Hilman <khilman@linaro.org>

While waking up CPU from off state using clock domain force wakeup, restore
the CPU power state to ON state before putting CPU clock domain under
hardware control. Otherwise CPU wakeup might fail. The change is recommended
for all OMAP4+ devices though the PRCM weakness was observed on OMAP5
devices first.

As a result of weakness, lock-up is observed inside the hardware state
machine of local CPU PRCM and results are UN-predictable as per designers.
In software testing, we have seen hard-locks most of the time where system
gets frozen. With power domain state restored, system behaves correctly.

So update the code accordingly.
Acked-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NKevin Hilman <khilman@linaro.org>

The initialization is done from the cpuidle framework.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Use the CPUIDLE_FLAG_TIMER_STOP and let the cpuidle framework
to handle the CLOCK_EVT_NOTIFY_BROADCAST_ENTER/EXIT when entering
this state.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

On OMAP platform, FIQ is reserved for secure environment only. If at all
the FIQ needs to be disabled, it involves going through security
API call. Hence the local_fiq_[enable/disable]() in the OMAP code is bogus.
On GP devices too, the fiq is disabled for non-secure software.

So just get rid of it.
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>

Fix the following sparse warnings in the OMAP3/4 CPUIdle code:

arch/arm/mach-omap2/cpuidle34xx.c:272:1: warning: symbol 'omap3_idle_dev' was not declared. Should it be static?
arch/arm/mach-omap2/cpuidle34xx.c:274:23: warning: symbol 'omap3_idle_driver' was not declared. Should it be static?
arch/arm/mach-omap2/cpuidle44xx.c:164:1: warning: symbol 'omap4_idle_dev' was not declared. Should it be static?
arch/arm/mach-omap2/cpuidle44xx.c:166:23: warning: symbol 'omap4_idle_driver' was not declared. Should it be static?

Also fix the following checkpatch warnings:

WARNING: please, no space before tabs
#44: FILE: arch/arm/mach-omap2/cpuidle34xx.c:105:
+^I.name = ^I"omap3_idle",$

WARNING: please, no space before tabs
#45: FILE: arch/arm/mach-omap2/cpuidle34xx.c:106:
+^I.owner = ^ITHIS_MODULE,$

ERROR: code indent should use tabs where possible
#211: FILE: arch/arm/mach-omap2/cpuidle44xx.c:74:
+                        /* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */$
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>

The new omap4 cpuidle implementation currently requires
ARCH_NEEDS_CPU_IDLE_COUPLED, which only works on SMP.

This patch makes it possible to build a non-SMP kernel
for that platform. This is not normally desired for
end-users but can be useful for testing.

Without this patch, building rand-0y2jSKT results in:

drivers/cpuidle/coupled.c: In function 'cpuidle_coupled_poke':
drivers/cpuidle/coupled.c:317:3: error: implicit declaration of function '__smp_call_function_single' [-Werror=implicit-function-declaration]

It's not clear if this patch is the best solution for
the problem at hand. I have made sure that we can now
build the kernel in all configurations, but that does
not mean it will actually work on an OMAP44xx.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Tony Lindgren <tony@atomide.com>

OMAP4 idle driver uses CLOCK_EVT_NOTIFY_BROADCAST_[ENTER/EXIT]
for broadcast clock events. But _ENTER/_EXIT doesn't really open
broadcast clock events and to explicitly setup the broadcast device,
CLOCK_EVT_NOTIFY_BROADCAST_ON should be used.

Add the missing CLOCK_EVT_NOTIFY_BROADCAST_ON clockevent notifications.
This will setup the broadcast timer in either periodic/oneshot modes
correctly. Recent clockevent infrastructure change 77b0d60c {leave the
broadcast device in shutdown mode when not needed} exposed this bug
leading to boot hangs in oneshot mode. Prior to this, periodic broadcast
mode was also broken. This change fixes both the periodic/oneshot broadcast
modes.

Discussion thread :
	https://lkml.org/lkml/2012/4/9/13Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

With coupled idle states, a failure for any CPU to hit a low power
state must be coordinated such that all CPUs abort.

On OMAP4, when entering a coupled state, CPU0 has to wait for CPU1 to
enter its low power state before it can enter its low power state.

This is implemented by letting CPU0 wait for the CPU1 powerdomain to
hit off.  However, there are conditions where CPU1 might abort/fail
and not hit off while CPU0 is waiting for it.  For example, a CPU1
wakeup or a failed attempt to hit off due to hardware conditions.

To avoid the deadlock where CPU0 would continually wait for CPU1 to
hit off-mode, this patch adds a flag to signal when each CPU has come
out of its low-power state.  CPU0 then checks whether CPU1 has hit off
*or* has already completed its attempt to hit off.  If the latter,
CPU0 must abort its attempt to hit a low-power state so the coupled
state enter method can return.

In addition, cpuidle_coupled_parallel_barrier() is used to ensure the
clearing of the 'done' flag is synchronized on all CPUs.
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

OMAP4 CPUDILE driver is converted mainly based on notes from the
coupled cpuidle patch series.

The changes include :
- Register both CPUs and C-states to cpuidle driver.
- Set struct cpuidle_device.coupled_cpus
- Set struct cpuidle_device.safe_state to non coupled state.
- Set CPUIDLE_FLAG_COUPLED in struct cpuidle_state.flags for each
  state that affects multiple cpus.
- Separate ->enter hooks for coupled & simple idle.
- CPU0 wait loop for CPU1 power transition.
- CPU1 wakeup mechanism for the idle exit.
- Enabling ARCH_NEEDS_CPU_IDLE_COUPLED for OMAP4.

Thanks to Kevin Hilman and Colin Cross on the suggestions/fixes
on the intermediate version of this patch.
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

The current Makefile compiles the cpuidle34xx.c and cpuidle44xx.c files
even if the cpuidle option is not set in the kernel.

This patch fixes this by creating a section in the Makefile where these
files are compiled only if the CONFIG_CPU_IDLE option is set.

This modification breaks an implicit dependency between CPU_IDLE and PM as
they belong to the same block in the Makefile. This is fixed in the Kconfig
by selecting explicitely PM is CPU_IDLE is set.

The linux coding style recommend to use no-op functions in the headers
when the subsystem is disabled instead of adding big section in C files.

This patch fix this also.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NRajendra Nayak <rnayak@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

We initialized it at compile time, no need to do that at boot
time.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

We are storing the 'omap4_idle_data' in the private data field
of the cpuidle device. As we are using this variable only in this file,
that does not really make sense. Let's use the global variable directly.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

We initialize the omap4_idle_data variable at compile time allowing us
to remove in the next patch the initialization done at boot time.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

Add the static declaration for the omap4_idle_data variable because its scope
is in the file only.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

We do not longer need this table as we defined the values
in the driver states.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

The cpuidle API allows to declare statically the states in the driver
structure. Let's use it.
We do no longer need the fill_cstate function called at runtime and
by the way adding more instructions at boot time.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

The 'valid' field is never used in the code, let's remove it.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

Enable core cpuidle timekeeping and irq enabling and remove that
handling from this code.
Signed-off-by: NRobert Lee <rob.lee@linaro.org>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Reviewed-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: NJean Pihet <j-pihet@ti.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

OMAP4 cpuidle driver is reporting the state requested by governor
rather than the actually attempted one.

This is obviously misleading sysfs and powertop cpuidle statistics.
Fix it so that stats are reported correctly.
Reported-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
[khilman@ti.com: minor changelog edits]
Signed-off-by: NKevin Hilman <khilman@ti.com>

CPU local timer(TWD) stops when the CPU is transitioning into
deeper C-States. Since these timers are not wakeup capable, we
need the wakeup capable global timer to program the wakeup time
depending on the next timer expiry.

It can be handled by registering a global wakeup capable timer along
with local timers marked with (mis)feature flag CLOCK_EVT_FEAT_C3STOP.
Then notify the clock events layer from idle code using
CLOCK_EVT_NOTIFY_BROADCAST_ENTER/EXIT).

ARM local timers are already marked with C3STOP feature. Add the
notifiers to OMAP4 CPU idle code for the broadcast entry and exit.
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NJean Pihet <j-pihet@ti.com>
Acked-by: NKevin Hilman <khilman@ti.com>
Tested-by: NVishwanath BS <vishwanath.bs@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>

Add OMAP4 CPUIDLE support. CPU1 is left with defualt idle and
the low power state for it is managed via cpu-hotplug.

This patch adds MPUSS low power states in cpuidle.

	C1 - CPU0 ON + CPU1 ON + MPU ON
	C2 - CPU0 OFF + CPU1 OFF + MPU CSWR
	C3 - CPU0 OFF + CPU1 OFF + MPU OSWR

OMAP4460 onwards, MPUSS power domain doesn't support OFF state any more
anymore just like CORE power domain. The deepest state supported is OSWr.
Ofcourse when MPUSS and CORE PD transitions to OSWR along with device
off mode, even the memory contemts are lost which is as good as
the PD off state.

On OMAP4 because of hardware constraints, no low power states are
targeted when both CPUs are online and in SMP mode. The low power
states are attempted only when secondary CPU gets offline to OFF
through hotplug infrastructure.

Thanks to Nicole Chalhoub <n-chalhoub@ti.com> for doing exhaustive
C-state latency profiling.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NJean Pihet <j-pihet@ti.com>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Tested-by: NVishwanath BS <vishwanath.bs@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>