linux-toradex.git/drivers/cpufreq/omap-cpufreq.c, branch v4.17

PM / OPP: Update OPP users to put reference

2017-01-30T08:22:21+00:00

This patch updates dev_pm_opp_find_freq_*() routines to get a reference
to the OPPs returned by them.

Also updates the users of dev_pm_opp_find_freq_*() routines to call
dev_pm_opp_put() after they are done using the OPPs.

As it is guaranteed the that OPPs wouldn't get freed while being used,
the RCU read side locking present with the users isn't required anymore.
Drop it as well.

This patch also updates all users of devfreq_recommended_opp() which was
returning an OPP received from the OPP core.

Note that some of the OPP core routines have gained
rcu_read_{lock|unlock}() calls, as those still use RCU specific APIs
within them.

Signed-off-by: Viresh Kumar 
Reviewed-by: Chanwoo Choi  [Devfreq]
Signed-off-by: Rafael J. Wysocki

remove lots of IS_ERR_VALUE abuses

2016-05-27T22:26:11+00:00

Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err < 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

 #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \
       unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro  - Linus ]

Signed-off-by: Arnd Bergmann 
Cc: Andrzej Hajda 
Cc: Andrew Morton 
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla  # For nvmem part
Signed-off-by: Linus Torvalds

cpufreq: Use consistent prefixing via pr_fmt

2016-04-08T23:35:18+00:00

Use the more common kernel style adding a define for pr_fmt.

Miscellanea:

o Remove now unused PFX defines

Signed-off-by: Joe Perches 
Acked-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

cpufreq: Convert printk(KERN_ to pr_

2016-04-08T23:35:18+00:00

Use the more common logging style.

Miscellanea:

o Coalesce formats
o Realign arguments
o Add a missing space between a coalesced format

Signed-off-by: Joe Perches 
Acked-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

cpufreq: drop owner assignment from platform_drivers

2014-10-20T14:20:24+00:00

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang

cpufreq: add 'freq_table' in struct cpufreq_policy

2014-03-12T00:06:00+00:00

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: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

cpufreq: introduce cpufreq_generic_get() routine

2014-01-17T01:00:44+00:00

CPUFreq drivers that use clock frameworks interface,i.e. clk_get_rate(),
to get CPUs clk rate, have similar sort of code used in most of them.

This patch adds a generic ->get() which will do the same thing for them.
All those drivers are required to now is to set .get to cpufreq_generic_get()
and set their clk pointer in policy->clk during ->init().

Acked-by: Hans-Christian Egtvedt 
Acked-by: Shawn Guo 
Acked-by: Linus Walleij 
Acked-by: Shawn Guo 
Acked-by: Stephen Warren 
Signed-off-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

cpufreq: Mark ARM drivers with CPUFREQ_NEED_INITIAL_FREQ_CHECK flag

2014-01-06T13:17:25+00:00

Sometimes boot loaders set CPU frequency to a value outside of frequency table
present with cpufreq core. In such cases CPU might be unstable if it has to run
on that frequency for long duration of time and so its better to set it to a
frequency which is specified in frequency table.

On some systems we can't really say what frequency we're running at the moment
and so for these we shouldn't check if we are running at a frequency present in
frequency table. And so we really can't force this for all the cpufreq drivers.

Hence we are created another flag here: CPUFREQ_NEED_INITIAL_FREQ_CHECK that
will be marked by platforms which want to go for this check at boot time.

Initially this is done for all ARM platforms but others may follow if required.

Signed-off-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

cpufreq: OMAP: Fix compilation error 'r & ret undeclared'

2013-11-13T23:52:48+00:00

With a recent change "d4019f0 cpufreq: move freq change notifications to cpufreq
core" few variables (r & ret) are removed by mistake and hence these warnings:

drivers/cpufreq/omap-cpufreq.c: In function omap_target:
drivers/cpufreq/omap-cpufreq.c:64:2: error: ret undeclared (first use in this function)
drivers/cpufreq/omap-cpufreq.c:64:2: note: each undeclared identifier is reported only once for each function it appears in
drivers/cpufreq/omap-cpufreq.c:94:3: error: r undeclared (first use in this function)
drivers/cpufreq/omap-cpufreq.c:116:1: warning: control reaches end of non-void function [-Wreturn-type]

Lets fix them by declaring those variables again.

Fixes: d4019f0a92ab (cpufreq: move freq change notifications to cpufreq core)
Reported-by: Sebastian Capella 
Signed-off-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki

cpufreq: move freq change notifications to cpufreq core

2013-10-30T23:11:08+00:00

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: Hans-Christian Egtvedt 
Acked-by: Jesper Nilsson 
Acked-by: Linus Walleij 
Acked-by: Russell King 
Acked-by: Stephen Warren 
Tested-by: Andrew Lunn 
Tested-by: Nicolas Pitre 
Reviewed-by: Lan Tianyu 
Signed-off-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki