During frequency transitions, the cpufreq core takes the responsibility of
invoking cpufreq_freq_transition_begin() and cpufreq_freq_transition_end()
for those cpufreq drivers that define the ->target_index callback but don't
set the ASYNC_NOTIFICATION flag.

The powernow-k7 cpufreq driver falls under this category, but this driver was
invoking the _begin() and _end() APIs itself around frequency transitions,
which led to double invocation of the _begin() API. The _begin API makes
contending callers wait until the previous invocation is complete. Hence,
the powernow-k7 driver ended up waiting on itself, leading to system hangs
during boot.

Fix this by removing the calls to the _begin() and _end() APIs from the
powernow-k7 driver, since they rightly belong to the cpufreq core.

Fixes: 12478cf0 (cpufreq: Make sure frequency transitions are serialized)
Signed-off-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

CPUFreq core has new infrastructure that would guarantee serialized calls to
target() or target_index() callbacks. These are called
cpufreq_freq_transition_begin() and cpufreq_freq_transition_end().

This patch converts existing drivers to use these new set of routines.
Reviewed-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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>

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>

Many common initializations of struct policy are moved to core now and hence
this driver doesn't need to do it. This patch removes such code.

Most recent of those changes is to call ->get() in the core after calling
->init().
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 powernow driver.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

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>

Chapter 14 of Documentation/CodingStyle says:

The preferred form for passing a size of a struct is the following:

	p = kmalloc(sizeof(*p), ...);

The alternative form where struct name is spelled out hurts
readability and introduces an opportunity for a bug when the pointer
variable type is changed but the corresponding sizeof that is passed
to a memory allocator is not.

This wasn't followed consistently in drivers/cpufreq, let's make it
more consistent by always following this rule.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the drivers/cpufreq uses of the __cpuinit macros
from all C files.

[1] https://lkml.org/lkml/2013/5/20/589

[v2: leave 2nd lines of args misaligned as requested by Viresh]
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: cpufreq@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Acked-by: NDirk Brandewie <dirk.j.brandewie@intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.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>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Commit fa8031ae ('cpufreq: Add support
for x86 cpuinfo auto loading v4') seems to have inadvertently changed
the matched CPU family number from 6 to 7.  Change it back.
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Acked-by: NThomas Renninger <trenn@suse.de>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This marks all the x86 cpuinfo tables to the CPU specific device drivers,
to allow auto loading by udev. This should simplify the distribution
startup scripts for this greatly.

I didn't add MODULE_DEVICE_IDs to the centrino and p4-clockmod drivers,
because those probably shouldn't be auto loaded and the acpi driver
be used instead (not fully sure on that, would appreciate feedback)

The old nforce drivers autoload based on the PCI ID.

ACPI cpufreq is autoloaded in another patch.

v3: Autoload gx based on PCI IDs only. Remove cpu check (Dave Jones)
v4: Use newly introduce HW_PSTATE feature for powernow-k8 loading

Cc: Dave Jones <davej@redhat.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NThomas Renninger <trenn@suse.de>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NDave Jones <davej@redhat.com>

With dynamic debug having gained the capability to report debug messages
also during the boot process, it offers a far superior interface for
debug messages than the custom cpufreq infrastructure. As a first step,
remove the old cpufreq_debug_printk() function and replace it with a call
to the generic pr_debug() function.

How can dynamic debug be used on cpufreq? You need a kernel which has
CONFIG_DYNAMIC_DEBUG enabled.

To enabled debugging during runtime, mount debugfs and

$ echo -n 'module cpufreq +p' > /sys/kernel/debug/dynamic_debug/control

for debugging the complete "cpufreq" module. To achieve the same goal during
boot, append

	ddebug_query="module cpufreq +p"

as a boot parameter to the kernel of your choice.

For more detailled instructions, please see
Documentation/dynamic-debug-howto.txt
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: NDave Jones <davej@redhat.com>

Use __cpuinit instead of __init for the cpufreq_driver
init function like it is done in powernow-k8.c.

This is removing the warning generated when compiling with
the CONFIG_DEBUG_SECTION_MISMATCH=y option.
Signed-off-by: NHolger Hans Peter Freyther <holger@moiji-mobile.com>
Signed-off-by: NDave Jones <davej@redhat.com>

This interface is mainly intended (and implemented) for ACPI _PPC BIOS
frequency limitations, but other cpufreq drivers can also use it for
similar use-cases.

Why is this needed:

Currently it's not obvious why cpufreq got limited.
People see cpufreq/scaling_max_freq reduced, but this could have
happened by:
  - any userspace prog writing to scaling_max_freq
  - thermal limitations
  - hardware (_PPC in ACPI case) limitiations

Therefore export bios_limit (in kHz) to:
  - Point the user that it's the BIOS (broken or intended) which limits
    frequency
  - Export it as a sysfs interface for userspace progs.
    While this was a rarely used feature on laptops, there will appear
    more and more server implemenations providing "Green IT" features like
    allowing the service processor to limit the frequency. People want
    to know about HW/BIOS frequency limitations.

All ACPI P-state driven cpufreq drivers are covered with this patch:
  - powernow-k8
  - powernow-k7
  - acpi-cpufreq

Tested with a patched DSDT which limits the first two cores (_PPC returns 1)
via _PPC, exposed by bios_limit:
# echo 2200000 >cpu2/cpufreq/scaling_max_freq
# cat cpu*/cpufreq/scaling_max_freq
2600000
2600000
2200000
2200000
# #scaling_max_freq shows general user/thermal/BIOS limitations

# cat cpu*/cpufreq/bios_limit
2600000
2600000
2800000
2800000
# #bios_limit only shows the HW/BIOS limitation

CC: Pallipadi Venkatesh <venkatesh.pallipadi@intel.com>
CC: Len Brown <lenb@kernel.org>
CC: davej@codemonkey.org.uk
CC: linux@dominikbrodowski.net
Signed-off-by: NThomas Renninger <trenn@suse.de>
Signed-off-by: NDave Jones <davej@redhat.com>

These are defined as static cpumask_var_t so if MAXSMP is not used,
they are cleared already.  Avoid surprises when MAXSMP is enabled.
Signed-off-by: NYinghai Lu <yinghai.lu@kernel.org>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

arch/x86/kernel/cpu/cpufreq/powernow-k7.c:172: warning: 'invalidate_entry' defined but not used
Reported-by: NToralf Förster <toralf.foerster@gmx.de>
Signed-off-by: NDave Jones <davej@redhat.com>

The asm/timer.h warning can be ignored, it's needed for
recalibrate_cpu_khz()
Signed-off-by: NDave Jones <davej@redhat.com>

GNU indent complains about this being ambiguous, because it's dumb.
One of my automated tests relies on the output of indent, so this shuts
it up.
Signed-off-by: NDave Jones <davej@redhat.com>

Impact: Reduce memory usage, use new API.

This is part of an effort to reduce structure sizes for machines
configured with large NR_CPUS.  cpumask_t gets replaced by
cpumask_var_t, which is either struct cpumask[1] (small NR_CPUS) or
struct cpumask * (large NR_CPUS).

(Changes to powernow-k* by <travis>.)
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Update assorted email addresses and related info to point
to a single current, valid address.

additionally
- trivial CREDITS entry updates. (Not that this file means much any more)
- remove arjans dead redhat.com address from powernow driver
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDave Jones <davej@redhat.com>

cpu_data is currently an array defined using NR_CPUS.  This means that
we overallocate since we will rarely really use maximum configured cpus.
When NR_CPU count is raised to 4096 the size of cpu_data becomes
3,145,728 bytes.

These changes were adopted from the sparc64 (and ia64) code.  An
additional field was added to cpuinfo_x86 to be a non-ambiguous cpu
index.  This corresponds to the index into a cpumask_t as well as the
per_cpu index.  It's used in various places like show_cpuinfo().

cpu_data is defined to be the boot_cpu_data structure for the NON-SMP
case.
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NChristoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The dmi const-ification missed acer_cpu_freq_pst. Fix it.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

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>

When the PST tables are broken, powernow-k7 uses ACPI's processor_perflib to
deduce the available frequency multipliers from the _PSS tables.

Upon frequency change, processor_perflib performs some verification on the
frequency (checks that it's within allowable bounds).

powernow-k7 deals with absolute frequencies in KHz, whereas perflib only
deals with MHz values. When performing the above verification, perflib
multiplies the MHz values by 1000 to obtain the KHz value.

We then end up with situations like the following:
 - powernow-k7 multiplies the multiplier by the FSB, and obtains a value
   such as 1266768 KHz
 - perflib belives the same state has frequency of 1266 MHz
 - acpi_processor_ppc_notifier calls cpufreq_verify_within_limits to verify
   that 1266768 is in the allowable range of 0 to 1266000 (i.e. 1266 * 1000)
 - it's not, so that frequency is rejected
 - the maximum CPU frequency is not reachable

This patch solves the problem by rounding up the MHz values stored in perflib's
tables. Additionally it corrects a broken URL.

It also fixes http://bugzilla.kernel.org/show_bug.cgi?id=8255 although this
case is a bit different: the frequencies in the _PSS tables are wildly wrong,
but we get better results if we force ACPI to respect the fsb * multiplier
calculations (even though it seems that the multiplier values aren't entirely
correct either).
Signed-off-by: NDaniel Drake <dsd@gentoo.org>
Signed-off-by: NDave Jones <davej@redhat.com>

This reverts commit aeeddc14, which was
half-baked and broken.  It just resulted in compile errors, since
cpufreq_register_driver() still changes the 'driver_data' by setting
bits in the flags field.  So claiming it is 'const' _really_ doesn't
work.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NDave Jones <davej@redhat.com>

Not all cases are possible due to ->flags being set at runtime
on some drivers.
Signed-off-by: NDave Jones <davej@redhat.com>

Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Even though powernow-k7 doesn't work in SMP environments,
it can work on an SMP configured kernel if there's only
one CPU present, however recalibrate_cpu_khz was returning
-EINVAL on such kernels, so we failed to init the cpufreq driver.
Signed-off-by: NDave Jones <davej@redhat.com>

This shouldn't have actually caused any problems
(as we return if we 'corrupt' 'i', but it's still not
very pretty.  For the sake of adding another local variable,
this got cleaner.
Signed-off-by: NDave Jones <davej@redhat.com>

Signed-off-by: NDave Jones <davej@redhat.com>

Signed-off-by: NDave Jones <davej@redhat.com>

Signed-off-by: NJesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>