Commit Graph

246 Commits

Author SHA1 Message Date
Masahiro Yamada 027f942ce4 clk: remove unnecessary !core->parents conditional
This if-block has been here since the introduction of the common
clock framework.  Now no clock drivers are statically initialized.
core->parent is always NULL at this point.  Drop the redundant
check and the confusing comment.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-01 17:01:39 -08:00
Masahiro Yamada be45ebf25f clk: rename __clk_init() into __clk_core_init()
Now this function takes clk_core as its argument.  __clk_core_init()
would be more suitable for the name of this function.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-01 17:01:36 -08:00
Masahiro Yamada d35c80c248 clk: change the argument of __clk_init() into pointer to clk_core
The argument clk_user is used only for the clk_user->core.  The rest
of this function only takes care of clk_core.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-01 17:01:32 -08:00
Masahiro Yamada d9e743408e clk: remove unused first argument of __clk_init()
The "struct device *dev" is not used at all in this function.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-01 17:01:28 -08:00
Michael Turquette a915e30dd2 Merge branch 'clk-rockchip' into clk-next 2015-12-23 13:08:56 -08:00
Heiko Stuebner 2eb8c7104c clk: add flag for clocks that need to be enabled on rate changes
Some clocks need to be enabled to accept rate changes. This patch adds a
new flag CLK_SET_RATE_UNGATE that lets clk_change_rate enable the clock
before trying to change the rate and disable it again afterwards.
This of course doesn't effect clocks that are already running at that
point, as their refcount will only temporarily increase.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Reviewed-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
2015-12-23 12:57:31 -08:00
Masahiro Yamada 8da411cc19 clk: let of_clk_get_parent_name() fail for invalid clock-indices
Currently, of_clk_get_parent_name() returns a wrong parent clock name
when "clock-indices" property exists and the target index is not
found in the property.  In this case, NULL should be returned.

For example,

        oscillator {
                compatible = "myclocktype";
                #clock-cells = <1>;
                clock-indices = <1>, <3>;
                clock-output-names = "clka", "clkb";
        };

        consumer {
                compatible = "myclockconsumer";
                clocks = <&oscillator 0>, <&oscillator 1>;
        };

Currently, of_clk_get_parent_name(consumer_np, 0) returns "clka"
(and of_clk_get_parent_name(consumer_np, 1) also returns "clka",
this is correct).   Because the "clock-indices" in the clock parent
does not contain <0>, of_clk_get_parent_name(consumer_np, 0) should
return NULL.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-12-02 22:34:43 -08:00
Masahiro Yamada 198bb59493 clk: fix a typo in comment block of clk_notifier_register()
The word "cases" is doubled.  Keep decent forms for the following
lines.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-11-30 11:36:07 -08:00
Geert Uytterhoeven 3fe003f944 clk: Spelling s/derefing/dereferencing/
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-11-20 11:17:55 -08:00
Masahiro Yamada c1de13574d clk: use IS_ERR_OR_NULL(hw) instead of !hw || IS_ERR(hw)
This minor refactoring does not change the function behavior.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-11-20 09:20:54 -08:00
Masahiro Yamada c736c4e11e clk: remove redundant negative index check in of_clk_get_parent_name()
This if-block can be dropped because the of_parse_phandle_with_args()
in the following line returns -EINVAL for negative index.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-11-20 09:18:24 -08:00
Joachim Eastwood be68bf8831 clk: Add clk_hw_is_enabled() for use by clk providers
Add clk_hw_is_enabled() to the provider APIs so clk providers can
use a struct clk_hw instead of a struct clk to check if a clk is
enabled or not.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-26 12:36:55 -07:00
Julia Lawall 6bc9d9d62c clk: add missing of_node_put
for_each_matching_node_and_match performs an of_node_get on each iteration,
so a break out of the loop requires an of_node_put.

A simplified version of the semantic patch that fixes this problem is as
follows (http://coccinelle.lip6.fr):

// <smpl>
@@
expression e1,e2,e;
local idexpression np;
@@

 for_each_matching_node_and_match(np, e1, e2) {
   ... when != of_node_put(np)
       when != e = np
(
   return np;
|
+  of_node_put(np);
?  return ...;
)
   ...
 }
// </smpl>

Besides the problem identified by the semantic patch, this patch adds an
of_node_get in front of saving np in a field of parent, to account for the
fact that this value will be put on going on to the next element in the
iteration, and then adds of_node_puts in the two loops where the parent
pointer can be freed.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-21 16:16:32 -07:00
Geert Uytterhoeven b76281cb97 clk: Make clk input parameter of __clk_get_name() const
When calling __clk_get_name() on a const clock:

    warning: passing argument 1 of '__clk_get_name' discards 'const' qualifier from pointer target type
    include/linux/clk-provider.h:613:13: note: expected 'struct clk *' but argument is of type 'const struct clk *'

__clk_get_name() does not modify the passed clock, hence make it const.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-16 11:56:19 -07:00
Geert Uytterhoeven 7e96353c3f clk: Use %u to format unsigned int in of_clk_src_onecell_get()
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-16 11:49:01 -07:00
Stephen Boyd 0a4807c2f9 clk: Make of_clk_get_parent_name() robust with #clock-cells = 1
If a clock provider has #clock-cells = 1 and we call
of_clk_get_parent_name() on it we may end up returning the name
of the provider node if the provider doesn't have a
clock-output-names property. This doesn't make sense, especially
when you consider that calling of_clk_get_parent_name() on such a
node with different indices will return the same name each time.

Let's try getting the clock from the framework via of_clk_get()
instead, and only fallback to the node name if we have a provider
with #clock-cells = 0. This way, we can't hand out the same name
for different clocks when we don't actually know their names.

Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-15 16:17:03 -07:00
Stephen Boyd ab5c342992 Merge branch 'clk-fixes' into clk-next
* clk-fixes:
  drivers: clk: st: Rename st_pll3200c32_407_c0_x into st_pll3200c32_cx_x
  clk: check for invalid parent index of orphans in __clk_init()
2015-09-17 12:28:41 -07:00
Javier Martinez Canillas 90c53547fc clk: Remove unneeded semicolons
There are cleary typo errors so can be removed.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-09-17 11:15:14 -07:00
Mans Rullgard 9054a31d60 clk: check for invalid parent index of orphans in __clk_init()
If a mux clock is initialised (by hardware or firmware) with an
invalid parent, its ->get_parent() can return an out of range
index.  For example, the generic mux clock attempts to return
-EINVAL, which due to the u8 return type ends up a rather large
number.  Using this index with the parent_names[] array results
in an invalid pointer and (usually) a crash in the following
strcmp().

This patch adds a check for the parent index being in range,
ignoring clocks reporting invalid values.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Tested-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-09-16 15:35:18 -07:00
Dong Aisheng c660b2ebb2 clk: remove duplicated code with __clk_set_parent_after
__clk_set_parent_after() actually used the second argument then we
could put this duplicate logic in there and call it with a different
order of arguments in the success vs. error paths in this function.

Cc: Mike Turquette <mturquette@linaro.org>
Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Dong Aisheng <aisheng.dong@freescale.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-08-24 16:49:13 -07:00
Stephen Boyd e7df6f6e21 clk: Constify clk_hw argument to provider APIs
We don't modify the clk_hw argument in these functions, so it's
safe to mark it as const.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-08-24 16:49:11 -07:00
Stephen Boyd fc4a05d4b0 clk: Remove unused provider APIs
Remove these APIs now that we've converted all users to the
replacement struct clk_hw based versions.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-08-24 16:49:02 -07:00
Stephen Boyd 1a9c069cb2 clk: Add clk_hw_*() APIs for use by clk providers
clk providers shouldn't need to use the consumer APIs (clk.h).
Add provider APIs to replace the __clk_*() APIs that take a
struct clk_hw as their first argument instead of a struct clk.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-08-24 16:48:42 -07:00
Heiko Stuebner e6500344ed clk: track the orphan status of clocks and their children
While children of orphan clocks are not carried in the orphan-list itself,
they're nevertheless orphans in their own right as they also don't have an
input-rate available. To ease tracking if a clock is an orphan or has an
orphan in its parent path introduce an orphan field into struct clk and
update it and the fields in child-clocks when a clock gets added or removed
from the orphan-list.

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Alex Elder <elder@linaro.org>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: kernel@pengutronix.de
Cc: Zhangfei Gao <zhangfei.gao@linaro.org>
Cc: Santosh Shilimkar <ssantosh@kernel.org>
Cc: Chao Xie <chao.xie@marvell.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Georgi Djakov <georgi.djakov@linaro.org>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Barry Song <baohua@kernel.org>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
Cc: Viresh Kumar <viresh.linux@gmail.com>
Cc: Gabriel FERNANDEZ <gabriel.fernandez@st.com>
Cc: emilio@elopez.com.ar
Cc: Peter De Schrijver <pdeschrijver@nvidia.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Michal Simek <michal.simek@xilinx.com>
[sboyd@codeaurora.org: s/clk/core/ in new function]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-08-12 00:59:18 -07:00
Stephen Boyd a57aa18539 clk: Silence warnings about lock imbalances
The recursive spinlock implementation trips up sparse and it
complains that these functions have lock imbalances. That isn't
really true though, so add some __acquires() and __releases()
information so that sparse is quiet.

drivers/clk/clk.c:116:22: warning: context imbalance in 'clk_enable_lock' - wrong count at exit
drivers/clk/clk.c:141:9: warning: context imbalance in 'clk_enable_unlock' - unexpected unlock

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-28 11:59:30 -07:00
Stephen Boyd 9cfad9bc47 Merge branch 'cleanup-clk-h-includes' into clk-next
* cleanup-clk-h-includes: (62 commits)
  clk: Remove clk.h from clk-provider.h
  clk: h8300: Remove clk.h and clkdev.h includes
  clk: at91: Include clk.h and slab.h
  clk: ti: Switch clk-provider.h include to clk.h
  clk: pistachio: Include clk.h
  clk: ingenic: Include clk.h
  clk: si570: Include clk.h
  clk: moxart: Include clk.h
  clk: cdce925: Include clk.h
  clk: Include clk.h in clk.c
  clk: zynq: Include clk.h
  clk: ti: Include clk.h
  clk: sunxi: Include clk.h and remove unused clkdev.h includes
  clk: st: Include clk.h
  clk: qcom: Include clk.h
  clk: highbank: Include clk.h
  clk: bcm: Include clk.h
  clk: versatile: Remove clk.h and clkdev.h includes
  clk: ux500: Remove clk.h and clkdev.h includes
  clk: tegra: Properly include clk.h
  ...
2015-07-28 11:59:09 -07:00
Stephen Boyd 9783c0d985 clk: Allow providers to configure min/max rates
clk providers are using the consumer APIs to set min/max rates on
the clock they're providing. To encourage clk providers to move
away from the consumer APIs, add a provider API to set the
min/max rate of a clock. The assumption is that this is done
before the clock can be requested via clk_get() and that the
clock rate is already within the boundaries of the min/max that's
configured.

Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-28 11:58:50 -07:00
Stephen Boyd 19aab27308 Merge branch 'clk-determine-rate-struct' into clk-next
* clk-determine-rate-struct:
  clk: fix some determine_rate implementations
  clk: change clk_ops' ->determine_rate() prototype
2015-07-28 11:51:30 -07:00
Boris Brezillon 57d866e606 clk: fix some determine_rate implementations
Some determine_rate implementations are not returning an error
when they failed to adapt the rate according to the rate request.
Fix them so that they return an error instead of silently
returning 0.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
CC: Jonathan Corbet <corbet@lwn.net>
CC: Tony Lindgren <tony@atomide.com>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: "Emilio López" <emilio@elopez.com.ar>
CC: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Tero Kristo <t-kristo@ti.com>
CC: Peter De Schrijver <pdeschrijver@nvidia.com>
CC: Prashant Gaikwad <pgaikwad@nvidia.com>
CC: Stephen Warren <swarren@wwwdotorg.org>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Alexandre Courbot <gnurou@gmail.com>
CC: linux-doc@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
CC: linux-omap@vger.kernel.org
CC: linux-mips@linux-mips.org
CC: linux-tegra@vger.kernel.org
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-27 18:13:32 -07:00
Boris Brezillon 0817b62cc0 clk: change clk_ops' ->determine_rate() prototype
Clock rates are stored in an unsigned long field, but ->determine_rate()
(which returns a rounded rate from a requested one) returns a long
value (errors are reported using negative error codes), which can lead
to long overflow if the clock rate exceed 2Ghz.

Change ->determine_rate() prototype to return 0 or an error code, and pass
a pointer to a clk_rate_request structure containing the expected target
rate and the rate constraints imposed by clk users.

The clk_rate_request structure might be extended in the future to contain
other kind of constraints like the rounding policy, the maximum clock
inaccuracy or other things that are not yet supported by the CCF
(power consumption constraints ?).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
CC: Jonathan Corbet <corbet@lwn.net>
CC: Tony Lindgren <tony@atomide.com>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: "Emilio López" <emilio@elopez.com.ar>
CC: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
CC: Peter De Schrijver <pdeschrijver@nvidia.com>
CC: Prashant Gaikwad <pgaikwad@nvidia.com>
CC: Stephen Warren <swarren@wwwdotorg.org>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Alexandre Courbot <gnurou@gmail.com>
CC: linux-doc@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
CC: linux-omap@vger.kernel.org
CC: linux-mips@linux-mips.org
CC: linux-tegra@vger.kernel.org
[sboyd@codeaurora.org: Fix parent dereference problem in
__clk_determine_rate()]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
[sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate
clocks without parents or a rate determining op]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-27 18:12:01 -07:00
Stephen Boyd 3c37311730 clk: Include clk.h in clk.c
This file implements the clk API and so it should include clk.h
directly instead of indirectly including it through
clk-provider.h.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-20 11:11:30 -07:00
Stephen Boyd 2573a02aa5 clk: Move clk_provider_list to scope of function using it
The list isn't used after of_clk_init() is called, so we don't
need to keep an empty list around after init. Put the list on the
stack.

Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-07 17:20:05 -07:00
Stephen Boyd 2e3b19f137 clk: Check for allocation errors in of_clk_init()
Dan Carpenter reports that we don't check the allocation here for
failure. Add a failure check and free any previously allocated
providers from the clk_provider_list.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-07 17:20:03 -07:00
Michael Turquette 2cd7b04328 clk: tegra: Changes for v4.2-rc1
This contains the EMC clock driver that's been exhaustively reviewed and
 tested. It also includes a change to the clock core that allows a clock
 provider to perform low-level reparenting of clocks. This is required by
 the EMC clock driver because the reparenting needs to be done at a very
 specific point in time during the EMC frequency switch.
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Merge tag 'tegra-for-4.2-clk' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into clk-next

clk: tegra: Changes for v4.2-rc1

This contains the EMC clock driver that's been exhaustively reviewed and
tested. It also includes a change to the clock core that allows a clock
provider to perform low-level reparenting of clocks. This is required by
the EMC clock driver because the reparenting needs to be done at a very
specific point in time during the EMC frequency switch.
2015-06-20 13:29:48 -07:00
Michael Turquette 85e88fab13 Merge branch 'clk-exynos-cpu-clk' into clk-next
Folded into this merge commit is a build error fix: s/clk/core in
clk_change_rate due to the new struct clk_core
2015-06-20 13:26:40 -07:00
Bartlomiej Zolnierkiewicz d8d919879e clk: add CLK_RECALC_NEW_RATES clock flag for Exynos cpu clock support
This flag is needed to fix the issue with wrong dividers being setup
by Common Clock Framework when using the new Exynos cpu clock support.

The issue happens because clk_core_set_rate_nolock()  calls
clk_calc_new_rates(clk, rate) before both pre/post clock notifiers have
a chance to run.  In case of Exynos cpu clock support pre/post clock
notifiers are registered for mout_apll clock which is a parent of armclk
cpu clock and dividers are modified in both pre and post clock notifier.
This results in wrong dividers values being later programmed by
clk_change_rate(top).  To workaround the problem CLK_RECALC_NEW_RATES
flag is added and it is set for mout_apll clock later so the correct
divider values are re-calculated after both pre and post clock notifiers
had run.

For example when using "performance" governor on Exynos4210 Origen board
the cpufreq-dt driver requests to change the frequency from 1000MHz to
1200MHz and after the change state of the relevant clocks is following:

Without use of CLK_GET_RATE_NOCACHE flag:

 fout_apll rate: 1200000000
         fout_apll_div_2 rate: 600000000
                 mout_clkout_cpu rate: 600000000
                         div_clkout_cpu rate: 600000000
                                 clkout_cpu rate: 600000000
         mout_apll rate: 1200000000
                 armclk rate: 1200000000
                 mout_hpm rate: 1200000000
                         div_copy rate: 300000000
                                 div_hpm rate: 300000000
                 mout_core rate: 1200000000
                         div_core rate: 1200000000
                                 div_core2 rate: 1200000000
                                         arm_clk_div_2 rate: 600000000
                                         div_corem0 rate: 300000000
                                         div_corem1 rate: 150000000
                                         div_periph rate: 300000000
                         div_atb rate: 300000000
                                 div_pclk_dbg rate: 150000000
                 sclk_apll rate: 1200000000
                         sclk_apll_div_2 rate: 600000000

With use of CLK_GET_RATE_NOCACHE flag:

 fout_apll rate: 1200000000
         fout_apll_div_2 rate: 600000000
                 mout_clkout_cpu rate: 600000000
                         div_clkout_cpu rate: 600000000
                                 clkout_cpu rate: 600000000
         mout_apll rate: 1200000000
                 armclk rate: 1200000000
                 mout_hpm rate: 1200000000
                         div_copy rate: 200000000
                                 div_hpm rate: 200000000
                 mout_core rate: 1200000000
                         div_core rate: 1200000000
                                 div_core2 rate: 1200000000
                                         arm_clk_div_2 rate: 600000000
                                         div_corem0 rate: 300000000
                                         div_corem1 rate: 150000000
                                         div_periph rate: 300000000
                         div_atb rate: 240000000
                                 div_pclk_dbg rate: 120000000
                 sclk_apll rate: 150000000
                         sclk_apll_div_2 rate: 75000000

Without this change cpufreq-dt driver showed ~10 mA larger energy
consumption when compared to cpufreq-exynos one when "performance"
cpufreq governor was used on Exynos4210 SoC based Origen board.

This issue was probably meant to be workarounded by use of
CLK_GET_RATE_NOCACHE and CLK_DIVIDER_READ_ONLY clock flags in
the original Exynos cpu clock patchset (in "[PATCH v12 6/6] clk:
samsung: remove unused clock aliases and update clock flags" patch)
but usage of these flags is not sufficient to fix the issue observed.

Cc: Thomas Abraham <thomas.ab@samsung.com>
Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
2015-06-20 12:17:41 -07:00
Maxime Coquelin 8c9a8a8f71 clk: Move debug_node field under DEBUG_FS flag in struct clk_core
The debug_node field is only used when DEBUG_FS config is selected,
so declare it only if DEBUG_FS is selected.

Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-06-10 14:21:22 -07:00
Dinh Nguyen 2e61dfb360 clk: of: helper for filling parent clock array and return num of parents
Sprinkled all through the platform clock drivers are code like this to
fill the clock parent array:

for (i = 0; i < num_parents; ++i)
	parent_names[i] = of_clk_get_parent_name(np, i);

The of_clk_parent_fill() will do the same as the code above, and while
at it, return the number of parents as well since the logic of the
function is to the walk the clock node to look for the parent.

Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
[sboyd@codeaurora.org: Fixed kernel-doc]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-06-05 18:10:33 -07:00
Shailendra Verma a59a516398 clk: Fix typo in clk_register() comment
Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-05-20 15:44:32 -07:00
Stephen Boyd 562ef0b098 clk: Silence sparse warnings about __clk_{get,put}()
drivers/clk/clk.c:2700:5: warning: symbol '__clk_get' was not declared. Should it be static?
drivers/clk/clk.c:2713:6: warning: symbol '__clk_put' was not declared. Should it be static?

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-05-14 17:11:17 -07:00
Tomeu Vizoso 42c86547f4 clk: Expose clk_hw_reparent() to providers
To be used by clock implementations for switching to a new parent during
rate change.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2015-05-13 15:17:08 +02:00
Stephen Boyd a633472519 clk: Add some more lockdep assertions
We don't check to make sure the enable_lock is held across
enable/disable and we don't check if the prepare_lock is held
across prepare/unprepare. Add some asserts to catch any future
locking problems.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-05-07 11:32:54 -07:00
Stephen Boyd 18e70efe3e Merge branch 'clk-fixes' into clk-next 2015-05-07 11:32:49 -07:00
Felipe Balbi 70e9f4dde0 clk: add newline character after dumping all clocks
clk_dump() will dump data about all clocks in JSON
format, but it misses a newline character at the
end of the JSON string. This patch adds that missing
newline character.

Signed-off-by: Felipe Balbi <balbi@ti.com>
[sboyd@codeaurora.org: Squelch checkpatch with seq_puts()]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-05-07 11:32:37 -07:00
Dong Aisheng d2a5d46b16 clk: add missing lock when call clk_core_enable in clk_set_parent
Before commit 035a61c314 ("clk: Make clk API return per-user
struct clk instances") we acquired the enable_lock in
__clk_set_parent_{before,after}() by means of calling
clk_enable(). After commit 035a61c314 we use clk_core_enable()
in place of the clk_enable(), and clk_core_enable() doesn't
acquire the enable_lock. This opens up a race condition between
clk_set_parent() and clk_enable(). Fix it.

Fixes: 035a61c314 ("clk: Make clk API return per-user struct clk instances")
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Dong Aisheng <aisheng.dong@freescale.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-05-06 16:58:53 -07:00
Stefan Wahren 7cb81136d2 clk: Fix JSON output in debugfs
key/value pairs in a JSON object must be separated by a comma.
After adding the properties "accuracy" and "phase" the JSON output
of /sys/kernel/debug/clk/clk_dump is invalid.

So add the missing commas to fix it.

Fixes: 5279fc402a ("clk: add clk accuracy retrieval support")
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
[sboyd@codeaurora.org: Added comment in function]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-05-01 18:25:08 -07:00
Stephen Boyd 6e5ab41b10 clk: Update some comments to reflect reality
The debugfs clk directory no longer expresses a clk tree. Update
the comments around that apporiately. Also drop comments about
prepare locks needing to be held as we have the proper
annotations with lockdep_assert_held().

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-04-30 16:28:41 -07:00
Stephen Boyd 4dff95dc94 clk: Remove forward declared function prototypes
Move the code around so that we don't need to declare function
prototypes at the start of the file. Simplify
clk_core_is_prepared() and clk_core_is_enabled() too to make the
diff easier to read.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-04-30 16:28:39 -07:00
Stephen Boyd 1f3e198342 clk: Remove impossible if condition in clk_core_get_phase()
This condition can't ever be true because this function is static
and it's always called with a non-NULL pointer.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-04-30 16:28:37 -07:00
Stephen Boyd d7d131512b clk: Drop unnecessary OOM prints
We don't need to print error messages when allocations fail.
We'll get a nice backtrace in such situations anyway.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-04-30 16:28:35 -07:00
Dong Aisheng 864e160ae5 clk: Squash __clk_{enable,disable}() into callers
These functions are only used in one place. Let's squash them
into their respective callers to save some lines.

Signed-off-by: Dong Aisheng <aisheng.dong@freescale.com>
[sboyd@codeaurora.org: Redo commit text, add NULL check in
clk_enable()]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-04-30 16:28:33 -07:00
Stephen Boyd d6968fca78 clk: s/clk/core/ for struct clk_core
While introducing struct clk_core we tried to minimize the diff
by changing the type of 'clk' variables from struct clk to struct
clk_core without changing the names of the variables. Now that
the split is complete, the code is slightly confusing when it
mixes variables called 'clk' and variables called 'core' that are
of the same type struct clk_core. Let's be consistent and use
'core' everywhere we have a struct clk_core pointer and 'clk'
when we have a struct clk pointer.

Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-04-30 16:28:24 -07:00
Boris Brezillon 03bc10ab5b clk: check ->determine/round_rate() return value in clk_calc_new_rates
->determine_rate() and ->round_rate() can return the closest rate to the
requested one or an error code.
clk_calc_new_rates is assuming these functions can't return a negative
value, which leads to a undefined behavior when the clk implementation
returns such an error code.
Fix this by returning NULL in case ->determine_rate() or ->round_rate()
returned an error code.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-04-12 21:09:49 -07:00
Stephen Boyd 5cf065f556 Merge branch 'clk-fixes' into clk-next 2015-03-12 12:20:36 -07:00
Stephen Boyd 306c342f9c clk: Replace of_clk_get_by_clkspec() with of_clk_get_from_provider()
of_clk_get_by_clkspec() has the same function signature as
of_clk_get_from_provider()

 struct clk *of_clk_get_by_clkspec(struct of_phandle_args
 *clkspec)
 struct clk *of_clk_get_from_provider(struct of_phandle_args
 *clkspec)

except of_clk_get_by_clkspec() checks to make sure clkspec is not
NULL. Let's remove of_clk_get_by_clkspec() and replace the
callers of it (clkconf.c) with of_clk_get_from_provider().

Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-03-12 12:20:34 -07:00
Stephen Boyd 50595f8b9e clk: Rename child_node to clks_node to avoid confusion
The child_node member of struct clk is named the same as the
child_node member of struct clk_core. Let's rename the struct
clk's member to clks_node to avoid getting confused with the
child_node member of struct clk_core and to match the name of the
list head, clks.

Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Alban Browaeys <alban.browaeys@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-03-12 12:20:32 -07:00
Stephen Boyd b61c43c09f clk: clk_set_parent() with current parent shouldn't fail
If a driver calls clk_set_parent(clk, parent) and parent is the
current parent of clk we shouldn't fail in any case.
Unfortunately if clk is a read-only mux we return -ENOSYS
because we think we can't change the parent, except for in this
special case where we don't actually need to change the parent at
all. Return 0 in such a situation.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-03-12 12:18:53 -07:00
Stephen Boyd dfc202ead3 clk: Add tracepoints for hardware operations
It's useful to have tracepoints around operations that change the
hardware state so that we can debug clock hardware performance
and operations. Four basic types of events are supported: on/off
events for enable, disable, prepare, unprepare that only record
an event and a clock name, rate changing events for
clk_set_{min_,max_}rate{_range}(), phase changing events for
clk_set_phase() and parent changing events for clk_set_parent().

Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-03-12 12:18:51 -07:00
Stephen Boyd 08b9575660 clk: Missing set_phase op is an error
If a clock's clk_ops doesn't have the set_phase op set we should
return an error from clk_set_phase(). This way clock consumers
know that when they tried to set a phase it didn't work, as
opposed to the current behavior where the return value is 0
meaning success.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-03-12 12:18:49 -07:00
Krzysztof Kozlowski 496eadf821 clk: Use lockdep asserts to find missing hold of prepare_lock
Add lockdep asserts for holding the prepare_lock to all functions
marking this as a requirement in description. Add this to private and
exported functions so all locking misuse could be detected during
debugging.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-03-12 12:18:45 -07:00
Michael Turquette 3d3801effd clk: introduce clk_is_match
Some drivers compare struct clk pointers as a means of knowing
if the two pointers reference the same clock hardware. This behavior is
dubious (drivers must not dereference struct clk), but did not cause any
regressions until the per-user struct clk patch was merged. Now the test
for matching clk's will always fail with per-user struct clk's.

clk_is_match is introduced to fix the regression and prevent drivers
from comparing the pointers manually.

Fixes: 035a61c314 ("clk: Make clk API return per-user struct clk instances")
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[arnd@arndb.de: Fix COMMON_CLK=N && HAS_CLK=Y config]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[sboyd@codeaurora.org: const arguments to clk_is_match() and
remove unnecessary ternary operation]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-03-11 15:56:59 -07:00
Julia Lawall f55ac0655a clk: don't export static symbol
The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
type T;
identifier f;
@@

static T f (...) { ... }

@@
identifier r.f;
declarer name EXPORT_SYMBOL_GPL;
@@

-EXPORT_SYMBOL_GPL(f);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Fixes: 035a61c314 "clk: Make clk API return per-user struct clk instances"
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-03-11 15:53:18 -07:00
Linus Torvalds 18a8d49973 The clock framework changes for 3.20 contain the usual driver additions,
enhancements and fixes mostly for ARM32, ARM64, MIPS and Power-based
 devices. Additionaly the framework core underwent a bit of surgery with
 two major changes. The boundary between the clock core and clock
 providers (e.g clock drivers) is now more well defined with dedicated
 provider helper functions. struct clk no longer maps 1:1 with the
 hardware clock but is a true per-user cookie which helps us tracker
 users of hardware clocks and debug bad behavior. The second major change
 is the addition of rate constraints for clocks. Rate ranges are now
 supported which are analogous to the voltage ranges in the regulator
 framework. Unfortunately these changes to the core created some
 breakeage. We think we fixed it all up but for this reason there are
 lots of last minute commits trying to undo the damage.
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Merge tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux

Pull clock framework updates from Mike Turquette:
 "The clock framework changes contain the usual driver additions,
  enhancements and fixes mostly for ARM32, ARM64, MIPS and Power-based
  devices.

  Additionally the framework core underwent a bit of surgery with two
  major changes:

   - The boundary between the clock core and clock providers (e.g clock
     drivers) is now more well defined with dedicated provider helper
     functions.  struct clk no longer maps 1:1 with the hardware clock
     but is a true per-user cookie which helps us tracker users of
     hardware clocks and debug bad behavior.

   - The addition of rate constraints for clocks.  Rate ranges are now
     supported which are analogous to the voltage ranges in the
     regulator framework.

  Unfortunately these changes to the core created some breakeage.  We
  think we fixed it all up but for this reason there are lots of last
  minute commits trying to undo the damage"

* tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux: (113 commits)
  clk: Only recalculate the rate if needed
  Revert "clk: mxs: Fix invalid 32-bit access to frac registers"
  clk: qoriq: Add support for the platform PLL
  powerpc/corenet: Enable CLK_QORIQ
  clk: Replace explicit clk assignment with __clk_hw_set_clk
  clk: Add __clk_hw_set_clk helper function
  clk: Don't dereference parent clock if is NULL
  MIPS: Alchemy: Remove bogus args from alchemy_clk_fgcs_detr
  clkdev: Always allocate a struct clk and call __clk_get() w/ CCF
  clk: shmobile: div6: Avoid division by zero in .round_rate()
  clk: mxs: Fix invalid 32-bit access to frac registers
  clk: omap: compile legacy omap3 clocks conditionally
  clkdev: Export clk_register_clkdev
  clk: Add rate constraints to clocks
  clk: remove clk-private.h
  pci: xgene: do not use clk-private.h
  arm: omap2+ remove dead clock code
  clk: Make clk API return per-user struct clk instances
  clk: tegra: Define PLLD_DSI and remove dsia(b)_mux
  clk: tegra: Add support for the Tegra132 CAR IP block
  ...
2015-02-21 12:30:30 -08:00
Tomeu Vizoso ec02ace8ca clk: Only recalculate the rate if needed
We don't really need to recalculate the effective rate of a clock when a
per-user clock is removed, if the constraints of the later aren't
limiting the requested rate.

This was causing problems with clocks that never had a rate set before,
as rate_req would be zero. Though this could be considered a bug in the
implementation of those clocks, this should be checked somewhere else.

Fixes: 1c8e600440 ("clk: Add rate constraints to clocks")
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-02-19 19:29:19 -08:00
Javier Martinez Canillas 9e0ad7d28a clk: Don't dereference parent clock if is NULL
The clock passed as an argument to clk_mux_determine_rate_flags()
has the CLK_SET_RATE_PARENT flag set but it has no parent, then a
NULL pointer will tried to be dereferenced.

This shouldn't happen since setting that flag for a clock with no
parent is a bug but the core should be robust to handle that case.

Fixes: 035a61c314 ("clk: Make clk API return per-user struct clk instances")
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-02-18 09:40:01 -08:00
Andrzej Hajda 612936f212 clk: convert clock name allocations to kstrdup_const
Clock subsystem frequently performs duplication of strings located in
read-only memory section.  Replacing kstrdup by kstrdup_const allows to
avoid such operations.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:36 -08:00
Stephen Boyd 73e0e496af clkdev: Always allocate a struct clk and call __clk_get() w/ CCF
of_clk_get_by_clkspec() returns a struct clk pointer but it
doesn't create a new handle for the consumers when we're using
the common clock framework. Instead it just returns whatever the
clk provider hands out. When the consumers go to call clk_put()
we get an Oops.

Unable to handle kernel paging request at virtual address 00200200
pgd = c0004000
[00200200] *pgd=00000000
Internal error: Oops: 805 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.19.0-rc1-00104-ga251361a-dirty #992
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
task: ee00b000 ti: ee088000 task.ti: ee088000
PC is at __clk_put+0x24/0xd0
LR is at clk_prepare_lock+0xc/0xec
pc : [<c03eef38>]    lr : [<c03ec1f4>]    psr: 20000153
sp : ee089de8  ip : 00000000  fp : 00000000
r10: ee02f480  r9 : 00000001  r8 : 00000000
r7 : ee031cc0  r6 : ee089e08  r5 : 00000000  r4 : ee02f480
r3 : 00100100  r2 : 00200200  r1 : 0000091e  r0 : 00000001
Flags: nzCv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c5387d  Table: 4000404a  DAC: 00000015
Process swapper/0 (pid: 1, stack limit = 0xee088238)
Stack: (0xee089de8 to 0xee08a000)
9de0:                   ee7c8f14 c03f0ec8 ee089e08 00000000 c0718dc8 00000001
9e00: 00000000 c04ee0f0 ee7e0844 00000001 00000181 c04edb58 ee2bd320 00000000
9e20: 00000000 c011dc5c ee16a1e0 00000000 00000000 c0718dc8 ee16a1e0 ee2bd1e0
9e40: c0641740 ee16a1e0 00000000 ee2bd320 c0718dc8 ee1d3e10 ee1d3e10 00000000
9e60: c0769a88 00000000 c0718dc8 00000000 00000000 c02c3124 c02c310c ee1d3e10
9e80: c07b4eec 00000000 c0769a88 c02c1d0c ee1d3e10 c0769a88 ee1d3e44 00000000
9ea0: c07091dc c02c1eb8 00000000 c0769a88 c02c1e2c c02c0544 ee005478 ee1676c0
9ec0: c0769a88 ee3a4e80 c0760ce8 c02c150c c0669b90 c0769a88 c0746cd8 c0769a88
9ee0: c0746cd8 ee2bc4c0 c0778c00 c02c24e0 00000000 c0746cd8 c0746cd8 c07091f0
9f00: 00000000 c0008944 c04f405c 00000025 ee00b000 60000153 c074ab00 00000000
9f20: 00000000 c074ab90 60000153 00000000 ef7fca5d c050860c 000000b6 c0036b88
9f40: c065ecc4 c06bc728 00000006 00000006 c074ab30 ef7fca40 c0739bdc 00000006
9f60: c0718dbc c0778c00 000000b6 c0718dc8 c06ed598 c06edd64 00000006 00000006
9f80: c06ed598 c003b438 00000000 c04e64f4 00000000 00000000 00000000 00000000
9fa0: 00000000 c04e64fc 00000000 c000e838 00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 c0c0c0c0 c0c0c0c0
[<c03eef38>] (__clk_put) from [<c03f0ec8>] (of_clk_set_defaults+0xe0/0x2c0)
[<c03f0ec8>] (of_clk_set_defaults) from [<c02c3124>] (platform_drv_probe+0x18/0xa4)
[<c02c3124>] (platform_drv_probe) from [<c02c1d0c>] (driver_probe_device+0x10c/0x22c)
[<c02c1d0c>] (driver_probe_device) from [<c02c1eb8>] (__driver_attach+0x8c/0x90)
[<c02c1eb8>] (__driver_attach) from [<c02c0544>] (bus_for_each_dev+0x54/0x88)
[<c02c0544>] (bus_for_each_dev) from [<c02c150c>] (bus_add_driver+0xd4/0x1d0)
[<c02c150c>] (bus_add_driver) from [<c02c24e0>] (driver_register+0x78/0xf4)
[<c02c24e0>] (driver_register) from [<c07091f0>] (fimc_md_init+0x14/0x30)
[<c07091f0>] (fimc_md_init) from [<c0008944>] (do_one_initcall+0x80/0x1d0)
[<c0008944>] (do_one_initcall) from [<c06edd64>] (kernel_init_freeable+0x108/0x1d4)
[<c06edd64>] (kernel_init_freeable) from [<c04e64fc>] (kernel_init+0x8/0xec)
[<c04e64fc>] (kernel_init) from [<c000e838>] (ret_from_fork+0x14/0x3c)
Code: ebfff4ae e5943014 e5942018 e3530000 (e5823000)

Let's create a per-user handle here so that clk_put() can
properly unlink it and free the handle. Now that we allocate a
clk structure here we need to free it if __clk_get() fails so
bury the __clk_get() call in __of_clk_get_from_provider(). We
need to handle the same problem in clk_get_sys() so export
__clk_free_clk() to clkdev.c and do the same thing, except let's
use a union to make this code #ifdef free.

This fixes the above crash, properly calls __clk_get() when
of_clk_get_from_provider() is called, and cleans up the clk
structure on the error path of clk_get_sys().

Fixes: 035a61c314 "clk: Make clk API return per-user struct clk instances"
Reported-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reported-by: Alban Browaeys <alban.browaeys@gmail.com>
Tested-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Alban Browaeys <prahal@yahoo.com>
Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-02-06 17:53:20 -08:00
Tomeu Vizoso 1c8e600440 clk: Add rate constraints to clocks
Adds a way for clock consumers to set maximum and minimum rates. This
can be used for thermal drivers to set minimum rates, or by misc.
drivers to set maximum rates to assure a minimum performance level.

Changes the signature of the determine_rate callback by adding the
parameters min_rate and max_rate.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[sboyd@codeaurora.org: set req_rate in __clk_init]
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: min/max rate for sun6i_ahb1_clk_determine_rate
                        migrated clk-private.h changes to clk.c]
2015-02-02 14:23:42 -08:00
Michael Turquette b09d6d9910 clk: remove clk-private.h
Private clock framework data structures should be private, surprisingly.

Now that all platforms and drivers have been updated to remove static
initializations of struct clk and struct clk_core objects and all
references to clk-private.h have been removed we can move the
definitions of these structures into drivers/clk/clk.c and delete the
header.

Additionally the ugly DEFINE_CLK macros have been removed. Those were
used for static definitions of struct clk objects. That practice is no
longer allowed.

Finally __clk_init is staticized as it is no longer declared in any
header.

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-02-02 14:23:41 -08:00
Tomeu Vizoso 035a61c314 clk: Make clk API return per-user struct clk instances
Moves clock state to struct clk_core, but takes care to change as little API as
possible.

struct clk_hw still has a pointer to a struct clk, which is the
implementation's per-user clk instance, for backwards compatibility.

The struct clk that clk_get_parent() returns isn't owned by the caller, but by
the clock implementation, so the former shouldn't call clk_put() on it.

Because some boards in mach-omap2 still register clocks statically, their clock
registration had to be updated to take into account that the clock information
is stored in struct clk_core now.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: adapted clk_has_parent to struct clk_core
                        applied OMAP3+ DPLL fix from Tero & Tony]
2015-02-02 14:22:19 -08:00
Tomeu Vizoso af0f349b29 clk: Remove __clk_register
As it has never been used.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-28 10:40:18 -08:00
Tomeu Vizoso c440525cb9 clk: Remove unneeded NULL checks
As clk_unprepare_unused_subtree and clk_disable_unused_subtree are
always called with a valid struct clk.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-28 10:40:18 -08:00
Maxime Ripard 9767b04fe6 clk: Export phase functions
The phase setter and getter were not exported until now, which was causing
build breakages when callers were compiled as module. Export these two
functions.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-27 11:52:43 -08:00
Stephen Boyd 15a02c1f6d clk: Add __clk_mux_determine_rate_closest
Some clock drivers want to find the closest rate on the input of
a mux instead of a rate that's less than or equal to the desired
rate. Add a generic mux function to support this.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Kenneth Westfield <kwestfie@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-27 11:48:39 -08:00
Srinivas Kandagatla 52bba9809a clk: Fix debugfs clk removal before inited
Some of the clks can be registered & unregistered before the clk related debugfs
entries are initialized at late_initcall. In the unregister path checking for only
dentry before clk_debug_init() would lead dangling pointers in the debug clk list,
because the list is already populated in register path and the clk pointer freed in
unregister path.
The side effect of not removing it from the list is either a null pointer
dereference or if lucky to boot the system, the number of clk entries in
debugfs disappear.

We could add more checks like if (inited && !clk->dentry) but just removing
the check for dentry made more sense as debugfs_remove_recursive() seems to be
safe with null pointers. This will ensure that the unregistering clk would be
removed from the debug list in all the code paths.

Without this patch kernel would crash with log:
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0204000
[00000000] *pgd=00000000
Internal error: Oops: 5 [#1] SMP ARM
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Tainted: G    B          3.19.0-rc3-00007-g412f9ba-dirty #840
Hardware name: Qualcomm (Flattened Device Tree)
task: ed948000 ti: ed944000 task.ti: ed944000
PC is at strlen+0xc/0x40
LR is at __create_file+0x64/0x1dc
pc : [<c04ee604>]    lr : [<c049f1c4>]    psr: 60000013
sp : ed945e40  ip : ed945e50  fp : ed945e4c
r10: 00000000  r9 : c1006094  r8 : 00000000
r7 : 000041ed  r6 : 00000000  r5 : ed4af998  r4 : c11b5e28
r3 : 00000000  r2 : ed945e38  r1 : a0000013  r0 : 00000000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c5787d  Table: 8020406a  DAC: 00000015
Process swapper/0 (pid: 1, stack limit = 0xed944248)
Stack: (0xed945e40 to 0xed946000)
5e40: ed945e7c ed945e50 c049f1c4 c04ee604 c0fc2fa4 00000000 ecb748c0 c11c2b80
5e60: c0beec04 0000011c c0fc2fa4 00000000 ed945e94 ed945e80 c049f3e0 c049f16c
5e80: 00000000 00000000 ed945eac ed945e98 c08cbc50 c049f3c0 ecb748c0 c11c2b80
5ea0: ed945ed4 ed945eb0 c0fc3080 c08cbc30 c0beec04 c107e1d8 ecdf0600 c107e1d8
5ec0: c107e1d8 ecdf0600 ed945f54 ed945ed8 c0208ed4 c0fc2fb0 c026a784 c04ee628
5ee0: ed945f0c ed945ef0 c0f5d600 c04ee604 c0f5d5ec ef7fcc7d c0b40ecc 0000011c
5f00: ed945f54 ed945f10 c026a994 c0f5d5f8 c04ecc00 00000007 ef7fcc95 00000007
5f20: c0e90744 c0dd0884 ed945f54 c106cde0 00000007 c117f8c0 0000011c c0f5d5ec
5f40: c1006094 c100609c ed945f94 ed945f58 c0f5de34 c0208e50 00000007 00000007
5f60: c0f5d5ec be9b5ae0 00000000 c117f8c0 c0af1680 00000000 00000000 00000000
5f80: 00000000 00000000 ed945fac ed945f98 c0af169c c0f5dd2c ed944000 00000000
5fa0: 00000000 ed945fb0 c020f298 c0af168c 00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 ebcc6d33 bfffca73
[<c04ee604>] (strlen) from [<c049f1c4>] (__create_file+0x64/0x1dc)
[<c049f1c4>] (__create_file) from [<c049f3e0>] (debugfs_create_dir+0x2c/0x34)
[<c049f3e0>] (debugfs_create_dir) from [<c08cbc50>] (clk_debug_create_one+0x2c/0x16c)
[<c08cbc50>] (clk_debug_create_one) from [<c0fc3080>] (clk_debug_init+0xdc/0x144)
[<c0fc3080>] (clk_debug_init) from [<c0208ed4>] (do_one_initcall+0x90/0x1e0)
[<c0208ed4>] (do_one_initcall) from [<c0f5de34>] (kernel_init_freeable+0x114/0x1e0)
[<c0f5de34>] (kernel_init_freeable) from [<c0af169c>] (kernel_init+0x1c/0xfc)
[<c0af169c>] (kernel_init) from [<c020f298>] (ret_from_fork+0x14/0x3c)
Code: c0b40ecc e1a0c00d e92dd800 e24cb004 (e5d02000)
---[ end trace b940e45b5e25c1e7 ]---

Fixes: 6314b6796e "clk: Don't hold prepare_lock across debugfs creation"
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-27 11:45:53 -08:00
Michael Turquette 57386798f7 Merge branch 'clk-has-parent' into clk-next 2015-01-24 16:58:40 -08:00
Thierry Reding 4e88f3de89 clk: Introduce clk_has_parent()
This new function is similar to clk_set_parent(), except that it doesn't
actually change the parent. It merely checks that the given parent clock
can be a parent for the given clock.

A situation where this is useful is to check that a particular setup is
valid before switching to it. One specific use-case for this is atomic
modesetting in the DRM framework where setting a mode is divided into a
check phase where a given configuration is validated before applying
changes to the hardware.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-24 16:56:55 -08:00
Stephen Boyd 4526e7b857 clk: Skip fetching index for single parent clocks
We don't need to fetch the parent index for clocks if they only
have one parent. Doing this also avoid an unnecessary allocation
for the parent cache.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-20 10:09:06 -08:00
Stanimir Varbanov c7662fc59c clk: fix possible null pointer dereference
The commit 646cafc6 (clk: Change clk_ops->determine_rate to
return a clk_hw as the best parent) opens a possibility for
null pointer dereference, fix this.

Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-17 11:33:57 -08:00
Stephen Boyd 89f7e9de59 clk: Really fix deadlock with mmap_sem
Commit 6314b6796e (clk: Don't hold prepare_lock across debugfs
creation, 2014-09-04) forgot to update one place where we hold
the prepare_lock while creating debugfs directories. This means
we still have the chance of a deadlock that the commit was trying
to fix. Actually fix it by moving the debugfs creation outside
the prepare_lock.

Cc: <stable@vger.kernel.org> # 3.18
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fixes: 6314b6796e "clk: Don't hold prepare_lock across debugfs creation"
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: removed lockdep_assert]
2014-12-15 17:02:06 -08:00
Tomeu Vizoso 646cafc6aa clk: Change clk_ops->determine_rate to return a clk_hw as the best parent
This is in preparation for clock providers to not have to deal with struct clk.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2014-12-03 16:21:37 -08:00
Tomeu Vizoso 61c7cddfad clk: change clk_debugfs_add_file to take a struct clk_hw
Instead of struct clk, as this should be only used by providers.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2014-12-03 15:15:35 -08:00
Tomeu Vizoso 920f1c7472 clk: Don't expose __clk_get_accuracy
As it's only used internally, in drivers/clk/clk.c.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2014-12-03 15:15:34 -08:00
Tomeu Vizoso 10cdfe54da clk: Don't try to use a struct clk* after it could have been freed
As __clk_release could call kfree on clk and then we wouldn't have a safe way
of getting the module that owns the clock.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Fixes: fcb0ee6a3d ("clk: Implement clk_unregister")
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2014-12-03 15:15:34 -08:00
Tomeu Vizoso 4afbe1760d clk: Remove unused function __clk_get_prepare_count
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2014-12-03 15:15:34 -08:00
Zhen Lei 40ba3f0ff2 clk: delete a local variable's repeated assignment
It's the same to the next statement, "ret = clk->parent". I think compiler will
optimize it, it's just not looking well.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2014-11-19 11:41:18 -08:00
Mike Turquette 4dc7ed32f3 Allwinner Clocks Additions for 3.18
The most important part of this serie is the addition of the phase API to
 handle the MMC clocks in the Allwinner SoCs.
 
 Apart from that, the A23 gained a new mbus driver, and there's a fix for a
 incorrect divider table on the APB0 clock.
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Merge tag 'sunxi-clocks-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux into clk-next

Allwinner Clocks Additions for 3.18

The most important part of this serie is the addition of the phase API to
handle the MMC clocks in the Allwinner SoCs.

Apart from that, the A23 gained a new mbus driver, and there's a fix for a
incorrect divider table on the APB0 clock.
2014-09-27 12:52:33 -07:00
Maxime Ripard 9824cf73c3 clk: Add a function to retrieve phase
The current phase API doesn't look into the actual hardware to get the phase
value, but will rather get it from a variable only set by the set_phase
function.

This will cause issue when the client driver will never call the set_phase
function, where we can end up having a reported phase that will not match what
the hardware has been programmed to by the bootloader or what phase is
programmed out of reset.

Add a new get_phase function for the drivers to implement so that we can get
this value.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Hans de Goede <hdegoede@redhat.com>
2014-09-27 08:57:51 +02:00
Mike Turquette e59c5371fb clk: introduce clk_set_phase function & callback
A common operation for a clock signal generator is to shift the phase of
that signal. This patch introduces a new function to the clk.h API to
dynamically adjust the phase of a clock signal. Additionally this patch
introduces support for the new function in the common clock framework
via the .set_phase call back in struct clk_ops.

Signed-off-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Hans de Goede <hdegoede@redhat.com>
2014-09-27 08:57:38 +02:00
Mike Turquette a52ae5a755 Merge branch 'clk-fixes' into clk-next 2014-09-17 11:47:56 -07:00
Stephen Boyd 6314b6796e clk: Don't hold prepare_lock across debugfs creation
Rob Clark reports a lockdep splat that involves the prepare_lock
chained with the mmap semaphore.

======================================================
[ INFO: possible circular locking dependency detected ]
3.17.0-rc1-00050-g07a489b #802 Tainted: G        W
-------------------------------------------------------
Xorg.bin/5413 is trying to acquire lock:
 (prepare_lock){+.+.+.}, at: [<c0781280>] clk_prepare_lock+0x88/0xfc

but task is already holding lock:
 (qcom_iommu_lock){+.+...}, at: [<c079f664>] qcom_iommu_unmap+0x1c/0x1f0

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #4 (qcom_iommu_lock){+.+...}:
       [<c079f860>] qcom_iommu_map+0x28/0x450
       [<c079eb50>] iommu_map+0xc8/0x12c
       [<c056c1fc>] msm_iommu_map+0xb4/0x130
       [<c05697bc>] msm_gem_get_iova_locked+0x9c/0xe8
       [<c0569854>] msm_gem_get_iova+0x4c/0x64
       [<c0562208>] mdp4_kms_init+0x4c4/0x6c0
       [<c056881c>] msm_load+0x2ac/0x34c
       [<c0545724>] drm_dev_register+0xac/0x108
       [<c0547510>] drm_platform_init+0x50/0xf0
       [<c0578a60>] try_to_bring_up_master.part.3+0xc8/0x108
       [<c0578b48>] component_master_add_with_match+0xa8/0x104
       [<c0568294>] msm_pdev_probe+0x64/0x70
       [<c057e704>] platform_drv_probe+0x2c/0x60
       [<c057cff8>] driver_probe_device+0x108/0x234
       [<c057b65c>] bus_for_each_drv+0x64/0x98
       [<c057cec0>] device_attach+0x78/0x8c
       [<c057c590>] bus_probe_device+0x88/0xac
       [<c057c9b8>] deferred_probe_work_func+0x68/0x9c
       [<c0259db4>] process_one_work+0x1a0/0x40c
       [<c025a710>] worker_thread+0x44/0x4d8
       [<c025ec54>] kthread+0xd8/0xec
       [<c020e9a8>] ret_from_fork+0x14/0x2c

-> #3 (&dev->struct_mutex){+.+.+.}:
       [<c0541188>] drm_gem_mmap+0x38/0xd0
       [<c05695b8>] msm_gem_mmap+0xc/0x5c
       [<c02f0b6c>] mmap_region+0x35c/0x6c8
       [<c02f11ec>] do_mmap_pgoff+0x314/0x398
       [<c02de1e0>] vm_mmap_pgoff+0x84/0xb4
       [<c02ef83c>] SyS_mmap_pgoff+0x94/0xbc
       [<c020e8e0>] ret_fast_syscall+0x0/0x48

-> #2 (&mm->mmap_sem){++++++}:
       [<c0321138>] filldir64+0x68/0x180
       [<c0333fe0>] dcache_readdir+0x188/0x22c
       [<c0320ed0>] iterate_dir+0x9c/0x11c
       [<c03213b0>] SyS_getdents64+0x78/0xe8
       [<c020e8e0>] ret_fast_syscall+0x0/0x48

-> #1 (&sb->s_type->i_mutex_key#3){+.+.+.}:
       [<c03fc544>] __create_file+0x58/0x1dc
       [<c03fc70c>] debugfs_create_dir+0x1c/0x24
       [<c0781c7c>] clk_debug_create_subtree+0x20/0x170
       [<c0be2af8>] clk_debug_init+0xec/0x14c
       [<c0208c70>] do_one_initcall+0x8c/0x1c8
       [<c0b9cce4>] kernel_init_freeable+0x13c/0x1dc
       [<c0877bc4>] kernel_init+0x8/0xe8
       [<c020e9a8>] ret_from_fork+0x14/0x2c

-> #0 (prepare_lock){+.+.+.}:
       [<c087c408>] mutex_lock_nested+0x70/0x3e8
       [<c0781280>] clk_prepare_lock+0x88/0xfc
       [<c0782c50>] clk_prepare+0xc/0x24
       [<c079f474>] __enable_clocks.isra.4+0x18/0xa4
       [<c079f614>] __flush_iotlb_va+0xe0/0x114
       [<c079f6f4>] qcom_iommu_unmap+0xac/0x1f0
       [<c079ea3c>] iommu_unmap+0x9c/0xe8
       [<c056c2fc>] msm_iommu_unmap+0x64/0x84
       [<c0569da4>] msm_gem_free_object+0x11c/0x338
       [<c05413ec>] drm_gem_object_handle_unreference_unlocked+0xfc/0x130
       [<c0541604>] drm_gem_object_release_handle+0x50/0x68
       [<c0447a98>] idr_for_each+0xa8/0xdc
       [<c0541c10>] drm_gem_release+0x1c/0x28
       [<c0540b3c>] drm_release+0x370/0x428
       [<c031105c>] __fput+0x98/0x1e8
       [<c025d73c>] task_work_run+0xb0/0xfc
       [<c02477ec>] do_exit+0x2ec/0x948
       [<c0247ec0>] do_group_exit+0x4c/0xb8
       [<c025180c>] get_signal+0x28c/0x6ac
       [<c0211204>] do_signal+0xc4/0x3e4
       [<c02116cc>] do_work_pending+0xb4/0xc4
       [<c020e938>] work_pending+0xc/0x20

other info that might help us debug this:

Chain exists of:
  prepare_lock --> &dev->struct_mutex --> qcom_iommu_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(qcom_iommu_lock);
                               lock(&dev->struct_mutex);
                               lock(qcom_iommu_lock);
  lock(prepare_lock);

 *** DEADLOCK ***

3 locks held by Xorg.bin/5413:
 #0:  (drm_global_mutex){+.+.+.}, at: [<c0540800>] drm_release+0x34/0x428
 #1:  (&dev->struct_mutex){+.+.+.}, at: [<c05413bc>] drm_gem_object_handle_unreference_unlocked+0xcc/0x130
 #2:  (qcom_iommu_lock){+.+...}, at: [<c079f664>] qcom_iommu_unmap+0x1c/0x1f0

stack backtrace:
CPU: 1 PID: 5413 Comm: Xorg.bin Tainted: G        W      3.17.0-rc1-00050-g07a489b #802
[<c0216290>] (unwind_backtrace) from [<c0211d8c>] (show_stack+0x10/0x14)
[<c0211d8c>] (show_stack) from [<c087a078>] (dump_stack+0x98/0xb8)
[<c087a078>] (dump_stack) from [<c027f024>] (print_circular_bug+0x218/0x340)
[<c027f024>] (print_circular_bug) from [<c0283e08>] (__lock_acquire+0x1d24/0x20b8)
[<c0283e08>] (__lock_acquire) from [<c0284774>] (lock_acquire+0x9c/0xbc)
[<c0284774>] (lock_acquire) from [<c087c408>] (mutex_lock_nested+0x70/0x3e8)
[<c087c408>] (mutex_lock_nested) from [<c0781280>] (clk_prepare_lock+0x88/0xfc)
[<c0781280>] (clk_prepare_lock) from [<c0782c50>] (clk_prepare+0xc/0x24)
[<c0782c50>] (clk_prepare) from [<c079f474>] (__enable_clocks.isra.4+0x18/0xa4)
[<c079f474>] (__enable_clocks.isra.4) from [<c079f614>] (__flush_iotlb_va+0xe0/0x114)
[<c079f614>] (__flush_iotlb_va) from [<c079f6f4>] (qcom_iommu_unmap+0xac/0x1f0)
[<c079f6f4>] (qcom_iommu_unmap) from [<c079ea3c>] (iommu_unmap+0x9c/0xe8)
[<c079ea3c>] (iommu_unmap) from [<c056c2fc>] (msm_iommu_unmap+0x64/0x84)
[<c056c2fc>] (msm_iommu_unmap) from [<c0569da4>] (msm_gem_free_object+0x11c/0x338)
[<c0569da4>] (msm_gem_free_object) from [<c05413ec>] (drm_gem_object_handle_unreference_unlocked+0xfc/0x130)
[<c05413ec>] (drm_gem_object_handle_unreference_unlocked) from [<c0541604>] (drm_gem_object_release_handle+0x50/0x68)
[<c0541604>] (drm_gem_object_release_handle) from [<c0447a98>] (idr_for_each+0xa8/0xdc)
[<c0447a98>] (idr_for_each) from [<c0541c10>] (drm_gem_release+0x1c/0x28)
[<c0541c10>] (drm_gem_release) from [<c0540b3c>] (drm_release+0x370/0x428)
[<c0540b3c>] (drm_release) from [<c031105c>] (__fput+0x98/0x1e8)
[<c031105c>] (__fput) from [<c025d73c>] (task_work_run+0xb0/0xfc)
[<c025d73c>] (task_work_run) from [<c02477ec>] (do_exit+0x2ec/0x948)
[<c02477ec>] (do_exit) from [<c0247ec0>] (do_group_exit+0x4c/0xb8)
[<c0247ec0>] (do_group_exit) from [<c025180c>] (get_signal+0x28c/0x6ac)
[<c025180c>] (get_signal) from [<c0211204>] (do_signal+0xc4/0x3e4)
[<c0211204>] (do_signal) from [<c02116cc>] (do_work_pending+0xb4/0xc4)
[<c02116cc>] (do_work_pending) from [<c020e938>] (work_pending+0xc/0x20)

We can break this chain if we don't hold the prepare_lock while
creating debugfs directories. We only hold the prepare_lock right
now because we're traversing the clock tree recursively and we
don't want the hierarchy to change during the traversal.
Replacing this traversal with a simple linked list walk allows us
to only grab a list lock instead of the prepare_lock, thus
breaking the lock chain.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-10 14:36:20 -07:00
Tero Kristo 067bb1741c clk: prevent erronous parsing of children during rate change
In some cases, clocks can switch their parent with clk_set_rate, for
example clk_mux can do this in some cases. Current implementation of
clk_change_rate uses un-safe list iteration on the clock children, which
will cause wrong clocks to be parsed in case any of the clock children
change their parents during the change rate operation. Fixed by using
the safe list iterator instead.

The problem was detected due to some divide by zero errors generated
by clock init on dra7-evm board, see discussion under
http://article.gmane.org/gmane.linux.ports.arm.kernel/349180 for details.

Fixes: 71472c0c06 ("clk: add support for clock reparent on set_rate")
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-03 12:09:14 -07:00
Chris Brand abeab450bf clk: Propagate any error return from debug_init()
If the .debug_init op is provided, it will be called by
clk_debug_create_one(). If debug_init() returns an error code,
clk_debug_create_one() will return -ENOMEM, regardless of the
value returned from debug_init(). Tweak the code to return
the actual value returned by debug_init() instead.

Signed-off-by: Chris Brand <chris.brand@linaro.org>
Reviewed-by: Matt Porter <mporter@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-07-29 17:13:48 -07:00
Sylwester Nawrocki 86be408bfb clk: Support for clock parents and rates assigned from device tree
This patch adds helper functions to configure clock parents and rates
as specified through 'assigned-clock-parents', 'assigned-clock-rates'
DT properties for a clock provider or clock consumer device.
The helpers are now being called by the bus code for the platform, I2C
and SPI busses, before the driver probing and also in the clock core
after registration of a clock provider.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-07-25 15:16:27 -07:00
Peter De Schrijver fb2b3c9f68 clk: define and export clk_debugs_add_file
Define and export a new function clk_debugs_add_file which adds a file
to a existing clock's debugfs directory. This can be used by clock
providers to add debugfs entries which are not related to a specific clock
type. Examples include the ability to measure the rate of a clock. It can
also be used by modules to create new debugfs entries. This is useful if you
want to expose features for testing which can potentially cause system
instability such as allowing to change a clock's rate from userspace.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-07-02 16:15:55 -07:00
Sachin Kamat 6b44c854b0 clk: Fix build warnings
‘all_lists’ and ‘orphan_list’ is accessed only when DEBUG_FS is defined.
Thus, make their compilation conditional to fix the below warnings introduced
by commit 27b8d5f723 ("clk: flatten clk tree in debugfs"):
drivers/clk/clk.c:40:27: warning: ‘all_lists’ defined but not used [-Wunused-variable]
drivers/clk/clk.c:46:27: warning: ‘orphan_list’ defined but not used [-Wunused-variable]

Signed-off-by: Sachin Kamat <sachin.kamat@samsung.com>
Cc: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-07-01 20:20:36 -07:00
Peter De Schrijver 27b8d5f723 clk: flatten clk tree in debugfs
This patch flattens the clk tree in CCF debugfs. Instead of representing the
clocks and their hierarchy as a directory structure under
/sys/kernel/debug/clk, each clock gets a single directory directly under
/sys/kernel/debug/clk. The orphans directory is replaced by a file called
clk_orphan_summary.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-06-26 12:55:04 -07:00
Arnd Bergmann 1cdf8ee2f8 clk: export __clk_round_rate for providers
Commit 99cbd064b0 ("clk: qcom: Support display RCG clocks") adds
a use of the __clk_round_rate in a clock provided that can be built
as a loadable module.

This exports the symbol to avoid the build error from compiling
the qcom clock as a module.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-06-03 10:38:16 -07:00
Geert Uytterhoeven fb8abb7aef clk: Neaten clk_summary output
- Limit ruler to 80 characters (was: 81),
  - Widen rate column by 1 for nicer spacing,
  - Right-align numbers and their column headers,
  - Move a newline to reduce the number of seq_printf() calls,
  - Use set_puts() for fixed strings.

Before:

   clock                        enable_cnt  prepare_cnt  rate        accuracy
---------------------------------------------------------------------------------
 extal                          2           2            20000000   0
    thermal                     1           1            20000000   0
    cp                          0           0            10000000   0
       tpu0                     0           0            10000000   0
       tmu0                     0           0            10000000   0
    main                        1           1            20000000   0
       pll3                     0           0            1600000000 0
          ddr                   0           0            200000000  0
          zb3d2                 0           0            200000000  0
          zb3                   0           0            400000000  0
       pll1                     4           4            1560000000 0
          oscclk                0           0            126953     0
          rclk                  1           1            31738      0
             cmt1               0           0            31738      0
             cmt0               1           1            31738      0
          imp                   0           0            390000000  0

After:

   clock                         enable_cnt  prepare_cnt        rate   accuracy
--------------------------------------------------------------------------------
 extal                                    2            2    20000000          0
    thermal                               1            1    20000000          0
    cp                                    0            0    10000000          0
       tpu0                               0            0    10000000          0
       tmu0                               0            0    10000000          0
    main                                  1            1    20000000          0
       pll3                               0            0  1600000000          0
          ddr                             0            0   200000000          0
          zb3d2                           0            0   200000000          0
          zb3                             0            0   400000000          0
       pll1                               4            4  1560000000          0
          oscclk                          0            0      126953          0
          rclk                            1            1       31738          0
             cmt1                         0            0       31738          0
             cmt0                         1            1       31738          0
          imp                             0            0   390000000          0

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-05-23 14:10:59 -07:00
Stephen Boyd 63589e92c2 clk: Ignore error and NULL pointers passed to clk_{unprepare, disable}()
This simplifies error paths in drivers that use optional clocks
by allowing the NULL or error pointer to be passed
unconditionally.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-04-30 11:51:50 -07:00