freq table is not per CPU but per policy, so it makes more sense to
keep it within struct cpufreq_policy instead of a per-cpu variable.

This patch does it. Over that, there is no need to set policy->freq_table
to NULL in ->exit(), as policy structure is going to be freed soon.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Most of the drivers do following in their ->target_index() routines:

	struct cpufreq_freqs freqs;
	freqs.old = old freq...
	freqs.new = new freq...

	cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);

	/* Change rate here */

	cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);

This is replicated over all cpufreq drivers today and there doesn't exists a
good enough reason why this shouldn't be moved to cpufreq core instead.

There are few special cases though, like exynos5440, which doesn't do everything
on the call to ->target_index() routine and call some kind of bottom halves for
doing this work, work/tasklet/etc..

They may continue doing notification from their own code as flag:
CPUFREQ_ASYNC_NOTIFICATION is already set for them.

All drivers are also modified in this patch to avoid breaking 'git bisect', as
double notification would happen otherwise.
Acked-by: NHans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: NJesper Nilsson <jesper.nilsson@axis.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NRussell King <linux@arm.linux.org.uk>
Acked-by: NStephen Warren <swarren@nvidia.com>
Tested-by: NAndrew Lunn <andrew@lunn.ch>
Tested-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Reviewed-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Currently, the prototype of cpufreq_drivers target routines is:

int target(struct cpufreq_policy *policy, unsigned int target_freq,
		unsigned int relation);

And most of the drivers call cpufreq_frequency_table_target() to get a valid
index of their frequency table which is closest to the target_freq. And they
don't use target_freq and relation after that.

So, it makes sense to just do this work in cpufreq core before calling
cpufreq_frequency_table_target() and simply pass index instead. But this can be
done only with drivers which expose their frequency table with cpufreq core. For
others we need to stick with the old prototype of target() until those drivers
are converted to expose frequency tables.

This patch implements the new light weight prototype for target_index() routine.
It looks like this:

int target_index(struct cpufreq_policy *policy, unsigned int index);

CPUFreq core will call cpufreq_frequency_table_target() before calling this
routine and pass index to it. Because CPUFreq core now requires to call routines
present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time.

This also marks target() interface as deprecated. So, that new drivers avoid
using it. And Documentation is updated accordingly.

It also converts existing .target() to newly defined light weight
.target_index() routine for many driver.
Acked-by: NHans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: NJesper Nilsson <jesper.nilsson@axis.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Acked-by: NRussell King <linux@arm.linux.org.uk>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Tested-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rjw@rjwysocki.net>

Use generic cpufreq_generic_init() routine instead of replicating the same code
here.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Most of the CPUFreq drivers do similar things in .exit() and .verify() routines
and .attr. So its better if we have generic routines for them which can be used
by cpufreq drivers then.

This patch uses these generic routines in the pasemi driver.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Powerpc is a mess of implicit includes by prom.h. Add the necessary
explicit includes to drivers in preparation of prom.h cleanup.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NGrant Likely <grant.likely@linaro.org>

Lets use cpufreq_table_validate_and_show() instead of calling
cpufreq_frequency_table_cpuinfo() and cpufreq_frequency_table_get_attr().
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

We don't need to set .owner = THIS_MODULE any more in cpufreq drivers
as this field isn't used any more by the cpufreq core.

This patch removes it and updates all dependent drivers accordingly.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Move cpufreq driver of powerpc platform to drivers/cpufreq.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The "index" field of struct cpufreq_frequency_table was never an
index and isn't used at all by the cpufreq core.  It only is useful
for cpufreq drivers for their internal purposes.

Many people nowadays blindly set it in ascending order with the
assumption that the core will use it, which is a mistake.

Rename it to "driver_data" as that's what its purpose is. All of its
users are updated accordingly.

[rjw: Changelog]
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

policy->cpus contains all online cpus that have single shared clock line. And
their frequencies are always updated together.

Many SMP system's cpufreq drivers take care of this in individual drivers but
the best place for this code is in cpufreq core.

This patch modifies cpufreq_notify_transition() to notify frequency change for
all cpus in policy->cpus and hence updates all users of this API.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NStephen Warren <swarren@nvidia.com>
Tested-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

commit f96972f2 "kernel/sys.c: call disable_nonboot_cpus() in
kernel_restart()"

added a call to disable_nonboot_cpus() on kernel_restart(), which tries
to shutdown all the CPUs except the first one. The issue with the PA
Semi, is that it does not support CPU hotplug.

When the call is made to __cpu_down(), it calls the notifiers
CPU_DOWN_PREPARE, and then tries to take the CPU down.

One of the notifiers to the CPU hotplug code, is the cpufreq. The
DOWN_PREPARE will call __cpufreq_remove_dev() which calls
cpufreq_driver->exit. The PA Semi exit handler unmaps regions of I/O
that is used by an interrupt that goes off constantly
(system_reset_common, but it goes off during normal system operations
too). I'm not sure exactly what this interrupt does.

Running a simple function trace, you can see it goes off quite a bit:

# tracer: function
#
#           TASK-PID    CPU#    TIMESTAMP  FUNCTION
#              | |       |          |         |
          <idle>-0     [001]  1558.859363: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.860112: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.861109: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [001]  1558.861361: .pasemi_system_reset_exception <-.system_reset_exception
          <idle>-0     [000]  1558.861437: .pasemi_system_reset_exception <-.system_reset_exception

When the region is unmapped, the system crashes with:

Disabling non-boot CPUs ...
Error taking CPU1 down: -38
Unable to handle kernel paging request for data at address 0xd0000800903a0100
Faulting instruction address: 0xc000000000055fcc
Oops: Kernel access of bad area, sig: 11 [#1]
PREEMPT SMP NR_CPUS=64 NUMA PA Semi PWRficient
Modules linked in: shpchp
NIP: c000000000055fcc LR: c000000000055fb4 CTR: c0000000000df1fc
REGS: c0000000012175d0 TRAP: 0300   Not tainted  (3.8.0-rc4-test-dirty)
MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI>  CR: 24000088  XER: 00000000
SOFTE: 0
DAR: d0000800903a0100, DSISR: 42000000
TASK = c0000000010e9008[0] 'swapper/0' THREAD: c000000001214000 CPU: 0
GPR00: d0000800903a0000 c000000001217850 c0000000012167e0 0000000000000000
GPR04: 0000000000000000 0000000000000724 0000000000000724 0000000000000000
GPR08: 0000000000000000 0000000000000000 0000000000000001 0000000000a70000
GPR12: 0000000024000080 c00000000fff0000 ffffffffffffffff 000000003ffffae0
GPR16: ffffffffffffffff 0000000000a21198 0000000000000060 0000000000000000
GPR20: 00000000008fdd35 0000000000a21258 000000003ffffaf0 0000000000000417
GPR24: 0000000000a226d0 c000000000000000 0000000000000000 0000000000000000
GPR28: c00000000138b358 0000000000000000 c000000001144818 d0000800903a0100
NIP [c000000000055fcc] .set_astate+0x5c/0xa4
LR [c000000000055fb4] .set_astate+0x44/0xa4
Call Trace:
[c000000001217850] [c000000000055fb4] .set_astate+0x44/0xa4 (unreliable)
[c0000000012178f0] [c00000000005647c] .restore_astate+0x2c/0x34
[c000000001217980] [c000000000054668] .pasemi_system_reset_exception+0x6c/0x88
[c000000001217a00] [c000000000019ef0] .system_reset_exception+0x48/0x84
[c000000001217a80] [c000000000001e40] system_reset_common+0x140/0x180
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

So that we can clean up the header files and not be relying
on implicit includes from device.h ---> module.h
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Change &cpu_online_map to cpu_online_mask.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

machine is compatible is an OF-specific call.  It should have
the of_ prefix to protect the global namespace.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NMichal Simek <monstr@monstr.eu>

This updates the cpufreq drivers in arch/powerpc so they build again
after the core cpufreq changes that broke them in commit
in835481d9.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

[Split from a larger patch - sfr]
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

When the PWRficient cpus are entered into powersavings states, the
astate is automatically dropped down to 0. While we still restore it
when we come out of idle, it can still cause some weird effects with
respect to performance (especially since it takes a while to ramp up to
higher astates).

So, to avoid this, don't enter power savings when the cpufreq driver
(or user) has set higher astates than 0.

The restore is still required, since there's a chance the astate has
been raised from the other cpu while the idling one was asleep.
Signed-off-by: NOlof Johansson <olof@lixom.net>

There will be more product numbers in the future than just PA6T-1682M,
but they will share much of the features. Remove some of the explicit
references and compatibility checks with 1682M, and replace most of them
with the more generic term "PWRficient".
Signed-off-by: NOlof Johansson <olof@lixom.net>
Acked-by: NMichael Buesch <mb@bu3sch.de>
Acked-by: NDoug Thompson <dougthompson@xmission.com>

Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDave Jones <davej@redhat.com>

Update the global cpu speed variable according to current cpufreq speed,
/proc/cpuinfo reports the actual speed.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Just another pass through arch/powerpc for old usages.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Cpufreq driver for PA Semi PWRficient processors.
Signed-off-by: NEgor Martovetsky <egor@pasemi.com>
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NPaul Mackerras <paulus@samba.org>