ARM: OMAP2+: PMU: Convert OMAP2/3 devices to use HWMOD

Convert OMAP2/3 devices to use HWMOD for creating a PMU device. To support PMU
on OMAP2 devices we only need to use MPU sub-system and so we can simply use
the MPU HWMOD to create the PMU device. To support PMU on OMAP3 devices, we need
to use the MPU and DEBUG sub-systems and so use these HWMODs to create the PMU
device for OMAP3.

The MPU HWMOD for OMAP2/3 devices is currently missing the PMU interrupt and so
add the PMU interrupt to the MPU HWMOD for these devices.

This change also moves the PMU code out of the mach-omap2/devices.c files into
its own pmu.c file as suggested by Kevin Hilman to de-clutter devices.c.

Cc: Ming Lei <ming.lei@canonical.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
ARM: OMAP4: Re-map the CTIs IRQs from MPU to DEBUGSS

In order to use the CTI interrupts inconjunction with the DEBUGSS we need to
re-map the CTI IRQs to the DEBUGSS HWMOD. The purpose for doing this is so we
can create a PMU device based upon the DEBUGSS HWMOD and use the CTI interrupts
for routing ARM PMU events for OMAP4430 devices.

This is based upon Benoit Cousson's patch [1].

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2011-November/073319.html

Cc: Ming Lei <ming.lei@canonical.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>

Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
ARM: OMAP4430: Create PMU device via HWMOD

For OMAP4430 PMU events are routed to the CPU via the cross trigger interface
(CTI) because there are no dedicated interrupts. In order to route the PMU
events via the CTI IRQs, the following modules must be enabled:

        l3_instr, l3_main_3, debugss

Therefore, build the arm-pmu device via these three HWMODs.

Cc: Ming Lei <ming.lei@canonical.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
ARM: OMAP2+: PMU: Add runtime PM support

The original implementation of this patch was done by Ming Lei for PMU on OMAP4
[1]. Since then the PM runtime calls have been moved into the ARM PMU code and
this greatly simplifies the changes.

The another differnce since the original version, is that it is no longer
necessary to call pm_runtime_get/put during the PMU initialisation was we are no
longer accessing the hardware at this stage.

By adding runtime PM support, we can ensure that the appropriate power and clock
domains are kept on while PMU is being used.

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2011-November/074153.html

Cc: Ming Lei <ming.lei@canonical.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
ARM: OMAP4: Route PMU IRQs to CTI IRQs

For OMAP4430 there are no dedicate PMU interrupts, however, PMU events can be
routed to via the CTI IRQs. This allows tools such as PERF and OPROFILE to work
on OMAP4430.

The idea is from Woodruff Richard in the disscussion about "Oprofile on
Pandaboard / Omap4" on pandaboard@googlegroups.com.

Ming's original patch was called "arm: omap4: support pmu" [1] and has been
renamed and modified by Jon Hunter. There main differences from the original
patch are ...

1. Instead of only configuring the CTI interrupt once during boot, the
   interrupts are configured everytime the the PMU is used. The reason for this
   is because during power transitions the CTI logic state will be lost and so
   we will need to configure the interrupts everytime they are used. This is
   accomplished by using the PM runtime callbacks which will be called whenever
   the PMU is used.
2. Assign the PMU events to different cross triggering channels. This prevents
   a single PMU event generating interrupts to both CPUs and hence can cause
   spurious interrupts to occur. Reported by Ming [2].

[1] http://marc.info/?l=linux-arm-kernel&m=132227620816504&w=2
[2] http://permalink.gmane.org/gmane.linux.linaro.devel/10532

Acked-by: Jean Pihet <j-pihet@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Woodruff Richard <r-woodruff2@ti.com>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
ARM: OMAP4: Enable PMU for OMAP4460/70

OMAP4460 and OMAP4470 devices have dedicated PMU interrupts and so add these
interrupts to the MPU HWMOD so we can use these for PMU events on these
devices. The PMU interrupts need to be the first interrupts in the array of
interrupts as the ARM PMU driver assumes this.

By using these dedicated interrupts we only need to enable the MPU sub-system
for PMU to work. This is different to OMAP4430 that did not have dedicated
interrupts and required other power domains such as the DEBUGSS to be enabled
so we could route the PMU events to the CTI interrupts. Hence, OMAP4460 and
OMAP4470 devices can use the same function to create the PMU device that is
using by OMAP2/3.

Cc: Ming Lei <ming.lei@canonical.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
ARM: OMAP2+: PMU: Add QoS constraint

When CPU-idle is enabled, the MPU sub-system will transition to low power
states during idle periods. If the PMU is active and the MPU sub-system
transitions to a low power state, such as retention, then the PMU context
will be lost and PMU events will stop. To prevent this from happening add a
QoS constraint whenever PMU is active to prevent the MPU sub-system from
transitioning to a low power state.

By default the PMU QoS constraint is set to -1 so it will not prevent any low
power states and when the PMU is enabled, it is set to 0, so that only C-state
C0 is allowed.

Cc: Ming Lei <ming.lei@canonical.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>

Signed-off-by: Jon Hunter <jon-hunter@ti.com>