This patch cleans up arch/arm/mach-omap2/clkt_clksel.c.  It:

- makes several functions static that are not called outside the file;

- adds documentation;

- makes some code paths easier to read (hopefully), by breaking up
  compound statements and removing redundant checks;

- converts some pr_err()s that indicate clock tree data problems into WARN()s,
  so they are more likely to be noticed;

- and moves omap2_clk_round_rate() back into mach-omap2/clock.c, its proper
  home, since it is not clksel-specific.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

The DEFAULT_RATE clksel_rate flag is essentially useless.  It was set
on some of the lowest divisors, which, when switching to a much
higher-rate parent, could have potentially resulted in rates that
exceeded the hardware specifications for downstream clocks in the
window between the clk_set_parent(), and a subsequent clk_set_rate().
It seems much safer to just remove the flag and always use the highest
available divisor (resulting in the lowest possible rate) after the
switch, and this patch does so.

Ideally, it would be best to first attempt to switch to a divisor that
matches the clock's rate with the previous parent, if at all possible.
But that is a project for some other day or some other person.  The
parent changing code is rarely used.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

The RATE_FIXED clock flag is pointless.  In the OMAP1 clock code, it
simply causes the omap1_clk_round_rate() function to return the
current rate of the clock.  omap1_clk_round_rate(), however, should
never be called for a fixed-rate clock, since none of these clocks
have a .round_rate function pointer set in their struct clk records.
Similarly, in the OMAP2+ clock code, the RATE_FIXED flag just causes
the clock code to emit a warning if the OMAP clock maintainer was
foolish enough to add a .round_rate function pointer to a fixed-rate
clock.  "Doctor, it hurts when I pretend that a fixed-rate clock is
rate-changeable."  "Then don't pretend that a fixed-rate clock is
rate-changeable."  It has no functional value.  This patch drops the
RATE_FIXED clock flag, removing it from all clocks that are so marked.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>

All of the clocks that are marked with DELAYED_APP are changed as part
of the virt_prcm_set OPP virtual clock.  On 24xx, these clocks all
need to be changed as part of a group to keep the clock tree
functional - hence the need for the VALID_CONFIG bit, which is not
present on later OMAPs.  These clocks should not be rate-changed
independently.  So prevent these clocks from being changed
independently by dropping their .round_rate and .set_rate function
pointers.  It then turns out that the DELAYED_APP clock flag is no
longer useful, so drop it and the associated code and renumber the
clock flags.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>

Move all clksel-related clock functions from mach-omap2/clock.c to
mach-omap2/clkt_clksel.c.  This is intended to make the clock code
easier to understand, since all of the functions needed to manage
clksel clocks are now located in their own file, rather than being
mixed with other, unrelated functions.

Clock debugging is also now more finely-grained, since the DEBUG macro
can now be defined for clksel clocks alon.  This should reduce
unnecessary console noise when debugging.

Also, if at some future point the mach-omap2/ directory is split
into OMAP2/3/4 variants, this clkt file can be moved to the plat-omap/
directory to be shared.

Thanks to Alexander Shishkin <virtuoso@slind.org> for his comments to
improve the patch description.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Alexander Shishkin <virtuoso@slind.org>

Move all DPLL-related clock functions from mach-omap2/clock.c to
mach-omap2/clkt_dpll.c.  This is intended to make the clock code
easier to understand, since all of the functions needed to manage
DPLLs are now located in their own file, rather than being mixed with
other, unrelated functions.

Clock debugging is also now more finely-grained, since the DEBUG macro
can now be defined for DPLLs alone.  This should reduce unnecessary
console noise when debugging.

Also, if at some future point the mach-omap2/ directory is split
into OMAP2/3/4 variants, this clkt file can be moved to the plat-omap/
directory to be shared.

Thanks to Alexander Shishkin <virtuoso@slind.org> for his comments to
improve the patch description.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Alexander Shishkin <virtuoso@slind.org>

The clockdomain related code being in place, it is not necessary to have
some part of the clock code commented out. This would help the validation of
the clockdomain functions using the clock level interfaces.
Signed-off-by: NAbhijit Pagare <abhijitpagare@ti.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

One of the OMAP1 clocks can use the fixed divisor recalculation code
introduced in the OMAP2 clock code, so rename the
omap2_fixed_divisor_recalc() function to omap_fixed_divisor_recalc()
and make it available to all OMAPs.  A followup patch converts the OMAP1
clock.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

An api at init for all dpll nodes seem to be
needed to reparent the dpll clk node to its
bypass clk in case the dpll is in bypass.
If not done this causes sequencing issues at init
during propogate_rate.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <b-cousson@ti.com>

Most of the dpll api's from dpll.c are reused for OMAP4.
This patch does extend a few api's for OMAP4 support.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <b-cousson@ti.com>

This patch adds dummy hooks for OMAP4 dpll api's. Removes
dummy hooks for clkdev api's and enables CLKDEV
for OMAP4.
Also comments clockdomain calls from within the clock
framework as its not supported yet for OMAP4.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <b-cousson@ti.com>

Move the remaining headers under plat-omap/include/mach
to plat-omap/include/plat. Also search and replace the
files using these headers to include using the right path.

This was done with:

#!/bin/bash
mach_dir_old="arch/arm/plat-omap/include/mach"
plat_dir_new="arch/arm/plat-omap/include/plat"
headers=$(cd $mach_dir_old && ls *.h)
omap_dirs="arch/arm/*omap*/ \
drivers/video/omap \
sound/soc/omap"
other_files="drivers/leds/leds-ams-delta.c \
drivers/mfd/menelaus.c \
drivers/mfd/twl4030-core.c \
drivers/mtd/nand/ams-delta.c"

for header in $headers; do
	old="#include <mach\/$header"
	new="#include <plat\/$header"
	for dir in $omap_dirs; do
		find $dir -type f -name \*.[chS] | \
			xargs sed -i "s/$old/$new/"
	done
	find drivers/ -type f -name \*omap*.[chS] | \
		xargs sed -i "s/$old/$new/"
	for file in $other_files; do
		sed -i "s/$old/$new/" $file
	done
done

for header in $(ls $mach_dir_old/*.h); do
	git mv $header $plat_dir_new/
done
Signed-off-by: NTony Lindgren <tony@atomide.com>

This patch modifies the clock, clockdomain and OMAP3 specific
powerdomain code to call the PM counter infrastructure whenever one or
more powerdomains might have changed state.
Signed-off-by: NPeter 'p2' De Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>

Some OMAP2/3 hardware modules have CM_IDLEST attributes that are not
handled by the current omap2_wait_clock_ready() code.  In preparation
for patches that fix the unusual devices, rename the function
omap2_wait_clock_ready() to omap2_wait_module_ready() and split it
into three parts:

1. A clkops-specific companion clock return function (by default,
   omap2_clk_dflt_find_companion())

2. A clkops-specific CM_IDLEST register address and bit shift return
   function (by default, omap2_clk_dflt_find_idlest())

3. Code to wait for the CM to indicate that the module is ready
   (omap2_cm_wait_idlest())

Clocks can now specify their own custom find_companion() and find_idlest()
functions; used in subsequent patches.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

with while (i++ < MAX_CLOCK_ENABLE_WAIT); i can reach MAX_CLOCK_ENABLE_WAIT + 1
after the loop, so if (i == MAX_CLOCK_ENABLE_WAIT) that's still success.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

Remove OMAP_PRM_REGADDR and use processor specific defines instead.

Also fold in a patch from Kevin Hilman to add _OFFSET #defines
for the PRCM registers to be used with the prm_[read|write]_* macros.
These are used extensively in the forthcoming OMAP PM support.

Also remove now unused OMAP2_PRM_BASE.
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Remove OMAP_PRM_REGADDR and use processor specific defines instead.

Also fold in a patch from Kevin Hilman to add _OFFSET #defines
for the PRCM registers to be used with the prm_[read|write]_* macros.
These are used extensively in the forthcoming OMAP PM support.

Also remove now unused OMAP2_PRM_BASE.
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

On our system we see the following messages:

Disabling unused clock "gpt2_ick"
Disabling unused clock "gpt3_ick"
Disabling unused clock "gpt4_ick"
Disabling unused clock "gpt5_ick"
...

The messages have KERN_INFO level and if you have serial
console, they normally go there. I do not think it is good
idea to print that much stuff there. Moreover, messages
are not properly prefixed and for mortals it is not
immeadietly clear where they come from.

Let's give them debugging level instead.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
[paul@pwsan.com: trimmed debugging output in patch description]

The CORE DPLL M2 frequency change code should use pr_debug(), not
pr_info(), for its debug messages.  Same with
omap2_clksel_round_rate_div().  While here, convert a few printk(KERN_ERR ..
into pr_err().
Signed-off-by: NPaul Walmsley <paul@pwsan.com>

Richard Woodruff writes:
| The historic usage of this has been against single use leaf clocks
| (1st instance of gptimer).  When it was used it did:
|       clk_get()
|       clk_set_parent()
|       clk_enable()
|
| This usage was ok for that. Use on a disabled clock is needed.
|
| If there are multiple users on the clock or it is enabled there are
| problems.
|
| The call can still be unfriendly if 2 different drivers are using the
| clock with their own clock get/enable. It might be the function should
| return an error if usecount != 0 to stop surprises.  It is all around
| better if the parenting is done when the clock is off.

This is a good reason to ensure that the clock is not enabled when
clk_set_parent() is called.
Acked-by: NRichard Woodruff <r-woodruff2@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This roughly corresponds with OMAP commits: 7d06c48, 3241b19,
88b5d9b, 18a5500, 9c909ac, 5c6497b, 8b1f0bd, 2ac1da8.

For both OMAP2 and OMAP3, we note the reference and bypass clocks in
the DPLL data structure.  Whenever we modify the DPLL rate, we first
ensure that both the reference and bypass clocks are enabled.  Then,
we decide whether to use the reference and DPLL, or the bypass clock
if the desired rate is identical to the bypass rate, and program the
DPLL appropriately.  Finally, we update the clock's parent, and then
disable the unused clocks.

This keeps the parents correctly balanced, and more importantly ensures
that the bypass clock is running whenever we reprogram the DPLL.  This
is especially important because the procedure for reprogramming the DPLL
involves switching to the bypass clock.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When changing the parent of a clock, it is necessary to keep the
clock use counts balanced otherwise things the parent state will
get corrupted.  Since we already disable and re-enable the clock,
we might as well use the recursive versions instead.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

_omap2_clksel_get_src_field() was returning the first entry which was
either the default _or_ applicable to the SoC.  This is wrong - we
should be returning the first default which is applicable to the SoC.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The error checks for omap2_divisor_to_clksel() and comment disagree with
the actual value returned on error.  Fix this to return the correct error
value.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

linux-omap source commit 33d000c99ee393fe2042f93e8422f94976d276ce
introduces a way to "dry run" clock changes before they're committed.
However, this involves putting logic to handle this into each and
every recalc function, and unfortunately due to the caching, led to
some bugs.

Solve both of issues by making the recalc methods always return the
clock rate for the clock, which the caller decides what to do with.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Based on a patch from Paul Walmsley <paul@pwsan.com>:

 omap2_clk_enable() should enable a clock's clockdomain before
 attempting to enable its parent clock's clockdomain.  Similarly, in
 the unlikely event that the parent clock enable fails, the clockdomain
 should be disabled.

 linux-omap source commit is 6d6e285e5a7912b1ea68fadac387304c914aaba8.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Based upon a patch from Paul Walmsley <paul@pwsan.com>:

 If _omap2_clk_enable() fails, the clock's usecount must be decremented
 by one no matter whether the clock has a parent or not.

but reorganised a bit.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Several parts of the OMAP2/3 clock code use wmb() to try to ensure
that the hardware write completes before continuing.  This approach is
problematic: wmb() only ensures that the write leaves the ARM.  It
does not ensure that the write actually reaches the endpoint device.
The endpoint device in this case - either the PRM, CM, or SCM - is
three interconnects away from the ARM - and the final interconnect is
low-speed.  And the OCP interconnects will post the write, and who
knows how long that will take to complete.  So the wmb() is not what
we want.  Worse, the wmb() is indiscriminate; it causes the ARM to
flush any other unrelated buffered writes and wait for the local
interconnect to acknowledge them - potentially very expensive.

Fix this by converting the wmb()s into readbacks of the same PRM/CM/SCM
register.  Since the PRM/CM/SCM devices use a single OCP thread, this
will cause the MPU to block while waiting for posted writes to that device
to complete.

linux-omap source commit is 260f5487848681b4d8ea7430a709a601bbcb21d1.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Consolidate the commit code for DELAYED_APP clocks into a subroutine,
_omap2xxx_clk_commit().  Also convert the MPU barrier wmb() into an
OCP barrier, since with an MPU barrier, we have no guarantee that the
write actually reached the endpoint device.

linux-omap source commit is 0f5bdb736515801b296125d16937a21ff7b3cfdc.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

clk_disable() previously used an ARM barrier, wmb(), to try to ensure
that the hardware write completed before continuing.  There are some
problems with this approach.

The first problem is that wmb() only ensures that the write leaves the
ARM -- not that it actually reaches the endpoint device.  In this
case, the endpoint device - either the PRM, CM, or SCM - is three
interconnects away from the ARM, and the final interconnect is
low-speed.  And the OCP interconnects will post the write, who knows
how long that will take to complete.  So the wmb() is not really what
we want.

Worse, the wmb() is indiscriminate; it will cause the ARM to flush any
other unrelated buffered writes and wait for the local interconnect to
acknowledge them - potentially very expensive.

This first problem could be fixed by doing a readback of the same PRM/CM/SCM
register.  Since these devices use a single OCP thread, this will cause the
MPU to wait for the write to complete.

But the primary problem is a conceptual one: clk_disable() should not
need any kind of barrier.  clk_enable() needs one since device driver
code must not access a device until its clocks are known to be
enabled.  But clk_disable() has no such restriction.

Since blocking the MPU on a PRM/CM/SCM write can be a very
high-latency operation - several hundred MPU cycles - it's worth
avoiding this barrier if possible.

linux-omap source commit is f4aacad2c0ed1055622d5c1e910befece24ef0e2.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Traditionally, we've tracked the parent/child relationships between
clk structures by setting the child's parent member to point at the
upstream clock.  As a result, when decending the tree, we have had
to scan all clocks to find the children.

Avoid this wasteful scanning by keeping a list of the clock's children.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Current implementation will disable clocks in the order defined in clock34xx.h,
at least DPLL4_M2X2 will hang in certain cases (and prevent retention / off)
if clocks are not disabled in correct order. This patch makes sure the parent
clocks will be active when disabling a clock.

linux-omap source commit is 672680063420ef8c8c4e7271984bb9cc08171d29.
Signed-off-by: NTero Kristo <tero.kristo@nokia.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Move the contents of the arch/arm/mach-omap2/memory.h file to the
existing mach/sdrc.h file, and remove memory.h.  Modify files which
include memory.h to include asm/arch/sdrc.h instead.

linux-omap source commit is e7ae2d89921372fc4b9712a32cc401d645597807.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch rolls up several cleanup patches.

1. Some unnecessarily verbose variable names are used in several clock.c
functions; clean these up per CodingStyle.

2. Remove omap2_get_clksel() and just use clk->clksel_reg and
clk->clksel_mask directly.

3. Get rid of void __iomem * usage in omap2_clksel_get_src_field.
Prepend the function name with an underscore to highlight that it is a
static function.

linux-omap source commits are 7fa95e007ea2f3c4d0ecd2779d809756e7775894,
af0ea23f1ee4a5bea3b026e38761b47089f9048a, and
91c0c979b47c44b08f80e4f8d4c990fb158d82c4.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The DPLL FREQSEL jitter correction bits are set based on a table in
the 34xx TRM, Table 4-38, according to the DPLL's internal clock
frequency "Fint."  Several Fint frequency ranges are missing from this
table.  Previously, we allowed these Fint frequency ranges to be
selected in the rate rounding code, but did not change the FREQSEL bits.
Correspondence with the OMAP hardware team indicates that Fint values
not in the table should not be used.  So, prevent them from being
selected during DPLL rate rounding.  This removes warnings and also
can prevent the chip from locking up.

The first pass through the rate rounding code will update the DPLL max
and min dividers appropriately, so later rate rounding passes will run
faster than the first.

Peter de Schrijver <peter.de-schrijver@nokia.com> put up with several
test cycles of this patch - thanks Peter.

linux-omap source commit is f9c1b82f55b60fc39eaa6e7aa1fbe380c0ffe2e9.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Peter de Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The previous DPLL rate rounding algorithm counted the divider (N) down
from the maximum to 1.  Since we currently use a broad DPLL rate
tolerance, and lower N values are more power-efficient, we can often
bypass several iterations through the loop by counting N upwards from
1.

Peter de Schrijver <peter.de-schrijver@nokia.com> put up with several
test cycles of this patch - thanks Peter.

linux-omap source commit is 6f6d82bb2f80fa20a841ac3e95a6f44a5a156188.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Peter de Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Remove some clutter from omap2_dpll_round_rate().

linux-omap source commit is 4625dceb8583c02a6d67ededc9f6a8347b6b8cb7.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Fix sparse & checkpatch warnings in OMAP2/3 PRCM & PM code.  This mostly
consists of:

- converting pointer comparisons to integers in form similar to
  (ptr == 0) to the standard idiom (!ptr)

- labeling a few non-static private functions as static

- adding prototypes for *_init() functions in the appropriate header
  files, and getting rid of the corresponding open-coded extern
  prototypes in other C files

- renaming the variable 'sclk' in mach-omap2/clock.c:omap2_get_apll_clkin
  to avoid shadowing an earlier declaration

Clean up checkpatch issues.  This mostly involves:

- converting some asm/ includes to linux/ includes

- cleaning up some whitespace

- getting rid of braces for conditionals with single following statements

Also take care of a few odds and ends, including:

- getting rid of unlikely() and likely() - none of this code is particularly
  fast-path code, so the performance impact seems slim; and some of those
  likely() and unlikely() indicators are probably not as accurate as the
  ARM's branch predictor

- removing some superfluous casts

linux-omap source commit is 347df59f5d20fdf905afbc26b1328b0e28a8a01b.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

propagate_rate() is recursive, so it makes sense to minimise the
amount of stack which is used for each recursion.  So, rather than
recursing back into it from the ->recalc functions if RATE_PROPAGATES
is set, do that test at the higher level.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Move the clock propagation calls for set_parent and set_rate into
the core omap clock code, rather than having these calls scattered
throughout the OMAP1 and OMAP2 implementations.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>