Commit Graph

190 Commits

Author SHA1 Message Date
Elaine Zhang ec52e46256 clk: fractional-divider: allow overriding of approximation
Fractional dividers may have special requirements concerning numerator
and denominator selection that differ from just getting the best
approximation.

For example on Rockchip socs the denominator must be at least 20 times
larger than the numerator to generate precise clock frequencies.

Therefore add the ability to provide custom approximation functions.

Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2017-08-08 17:39:48 +02:00
Maxime Ripard 22833a9165 clk: divider: Make divider_round_rate take the parent clock
So far, divider_round_rate only considers the parent clock returned by
clk_hw_get_parent.

This works fine on clocks that have a single parents, this doesn't work on
muxes, since we will only consider the first parent, while other parents
may totally be able to provide a better combination.

Clocks in that case cannot use divider_round_rate, so would have to come up
with a very similar logic to work around it. Instead of having to do
something like this, and duplicate that logic everywhere, create a
divider_round_rate parent to allow caller to give an additional parameter
for the parent clock to consider.

Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2017-06-07 15:32:12 +02:00
Shawn Guo 339e1e5489 clk: core: add __init decoration for CLK_OF_DECLARE_DRIVER function
The new introduced macro CLK_OF_DECLARE_DRIVER is usually used to
declare clock driver init functions, which are mostly decorated with
__init.  Add __init decoration for CLK_OF_DECLARE_DRIVER function to
avoid causing section mismatch warnings on client clock drivers.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Fixes: c7296c51ce ("clk: core: New macro CLK_OF_DECLARE_DRIVER")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-10-17 15:27:27 -07:00
Masahiro Yamada 5963f19ca2 clk: change the type of clk_hw_onecell_data.num to unsigned int
The "num" is the number of clk_hw entries in the structure, so
"unsigned int" would be a better fit.  (size_t looks like data
size we count by byte.)

Besides, struct clk_onecell_data already uses unsigned int for
"clk_num".

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-09-23 14:44:03 -07:00
Rafał Miłecki d42c047245 clk: return unsigned int in dummy non-OF of_clk_get_parent_count()
In the commit 929e7f3bc7 ("clk: Make of_clk_get_parent_count() return
unsigned ints") of_clk_get_parent_count has been modified to return
unsigned int. There is also a dummy implementation of the same function
for configs without CONFIG_OF. For the consistency it should be updated
as well.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-08-26 12:27:28 -07:00
Ricardo Ribalda Delgado c7296c51ce clk: core: New macro CLK_OF_DECLARE_DRIVER
This will be used by drivers that requires initialization at
of_clk_init() time and also during platform device probing.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-08-12 18:00:34 -07:00
Dong Aisheng a4b3518d14 clk: core: support clocks which requires parents enable (part 1)
On Freescale i.MX7D platform, all clocks operations, including
enable/disable, rate change and re-parent, requires its parent
clock enable. Current clock core can not support it well.
This patch introduce a new flag CLK_OPS_PARENT_ENABLE to handle this
special case in clock core that enable its parent clock firstly for
each operation and disable it later after operation complete.

The patch part 1 fixes the possible disabling clocks while its parent
is off during kernel booting phase in clk_disable_unused_subtree().

Before the completion of kernel booting, clock tree is still not built
completely, there may be a case that the child clock is on but its
parent is off which could be caused by either HW initial reset state
or bootloader initialization.

Taking bootloader as an example, we may enable all clocks in HW by default.
And during kernel booting time, the parent clock could be disabled in its
driver probe due to calling clk_prepare_enable and clk_disable_unprepare.
Because it's child clock is only enabled in HW while its SW usecount
in clock tree is still 0, so clk_disable of parent clock will gate
the parent clock in both HW and SW usecount ultimately. Then there will
be a child clock is still on in HW but its parent is already off.

Later in clk_disable_unused(), this clock disable accessing while its
parent off will cause system hang due to the limitation of HW which
must require its parent on.

This patch simply enables the parent clock first before disabling
if flag CLK_OPS_PARENT_ENABLE is set in clk_disable_unused_subtree().
This is a simple solution and only affects booting time.

After kernel booting up the clock tree is already created, there will
be no case that child is off but its parent is off.
So no need do this checking for normal clk_disable() later.

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-07-01 17:40:23 -07:00
Stephen Boyd 37bcfe9aba Merge branch 'clk-hw-unregister-fixed-rate' into clk-next
* clk-hw-unregister-fixed-rate:
  clk: fixed-rate: add clk_hw_unregister_fixed_rate()
2016-06-30 13:07:58 -07:00
Masahiro Yamada 5244563737 clk: fixed-rate: add clk_hw_unregister_fixed_rate()
This will be used to migrate to the clk_hw APIs.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-06-30 13:07:10 -07:00
Stephen Boyd b9610e7458 clk: Remove CLK_IS_ROOT flag
Now that we've gotten rid of all the users of this flag we can
retire the number, leaving a slot open for a future flag user.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-06-01 14:56:57 -07:00
Stephen Boyd 58657d189a Merge branch 'clk-hw-register' (early part) into clk-next
* 'clk-hw-register' (early part):
  clk: fixed-rate: Add hw based registration APIs
  clk: gpio: Add hw based registration APIs
  clk: composite: Add hw based registration APIs
  clk: fractional-divider: Add hw based registration APIs
  clk: fixed-factor: Add hw based registration APIs
  clk: mux: Add hw based registration APIs
  clk: gate: Add hw based registration APIs
  clk: divider: Add hw based registration APIs
  clkdev: Add clk_hw based registration APIs
  clk: Add clk_hw OF clk providers
  clk: Add {devm_}clk_hw_{register,unregister}() APIs
  clkdev: Remove clk_register_clkdevs()
2016-04-21 14:47:18 -07:00
Stephen Boyd e9471c4ecf Merge branch 'clk-composite-unregister' into clk-next
* clk-composite-unregister:
  clk: composite: Add unregister function
2016-04-21 14:43:56 -07:00
Maxime Ripard 92a39d9043 clk: composite: Add unregister function
The composite clock didn't have any unregistration function, which forced
us to use clk_unregister directly on it.

While it was already not great from an API point of view, it also meant
that we were leaking the clk_composite structure allocated in
clk_register_composite.

Add a clk_unregister_composite function to fix this.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-21 14:43:28 -07:00
Stephen Boyd 26ef56be9e clk: fixed-rate: Add hw based registration APIs
Add registration APIs in the clk fixed-rate code to return struct
clk_hw pointers instead of struct clk pointers. This way we hide
the struct clk pointer from providers unless they need to use
consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:57:12 -07:00
Stephen Boyd b120743a64 clk: gpio: Add hw based registration APIs
Add registration APIs in the clk gpio code to return struct
clk_hw pointers instead of struct clk pointers. This way we hide
the struct clk pointer from providers unless they need to use
consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:56:28 -07:00
Stephen Boyd 49cb392d36 clk: composite: Add hw based registration APIs
Add registration APIs in the clk composite code to return struct
clk_hw pointers instead of struct clk pointers. This way we hide
the struct clk pointer from providers unless they need to use
consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:56:28 -07:00
Stephen Boyd 39b44cff4a clk: fractional-divider: Add hw based registration APIs
Add registration APIs in the clk fractional divider code to
return struct clk_hw pointers instead of struct clk pointers.
This way we hide the struct clk pointer from providers unless
they need to use consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:56:28 -07:00
Stephen Boyd 0759ac8a73 clk: fixed-factor: Add hw based registration APIs
Add registration APIs in the clk fixed-factor code to return
struct clk_hw pointers instead of struct clk pointers. This way
we hide the struct clk pointer from providers unless they need to
use consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:56:28 -07:00
Stephen Boyd 264b317197 clk: mux: Add hw based registration APIs
Add registration APIs in the clk mux code to return struct clk_hw
pointers instead of struct clk pointers. This way we hide the
struct clk pointer from providers unless they need to use
consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:55:01 -07:00
Stephen Boyd e270d8cb13 clk: gate: Add hw based registration APIs
Add registration APIs in the clk gate code to return struct
clk_hw pointers instead of struct clk pointers. This way we hide
the struct clk pointer from providers unless they need to use
consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:55:01 -07:00
Stephen Boyd eb7d264f3b clk: divider: Add hw based registration APIs
Add registration APIs in the clk divider code to return struct
clk_hw pointers instead of struct clk pointers. This way we hide
the struct clk pointer from providers unless they need to use
consumer facing APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:55:01 -07:00
Stephen Boyd 0861e5b8cf clk: Add clk_hw OF clk providers
Now that we have a clk registration API that doesn't return
struct clks, we need to have some way to hand out struct clks via
the clk_get() APIs that doesn't involve associating struct clk
pointers with an OF node. Currently we ask the OF provider to
give us a struct clk pointer for some clkspec, turn that struct
clk into a struct clk_hw and then allocate a new struct clk to
return to the caller.

Let's add a clk_hw based OF provider hook that returns a struct
clk_hw directly, so that we skip the intermediate step of
converting from struct clk to struct clk_hw. Eventually when
we've converted all OF clk providers to struct clk_hw based APIs
we can remove the struct clk based ones.

It should also be noted that we change the onecell provider to
have a flex array instead of a pointer for the array of clk_hw
pointers. This allows providers to allocate one structure of the
correct length in one step instead of two.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:52:22 -07:00
Stephen Boyd 4143804c4f clk: Add {devm_}clk_hw_{register,unregister}() APIs
We've largely split the clk consumer and provider APIs along
struct clk and struct clk_hw, but clk_register() still returns a
struct clk pointer for each struct clk_hw that's registered.
Eventually we'd like to only allocate struct clks when there's a
user, because struct clk is per-user now, so clk_register() needs
to change.

Let's add new APIs to register struct clk_hws, but this time
we'll hide the struct clk from the caller by returning an int
error code. Also add an unregistration API that takes the clk_hw
structure that was passed to the registration API. This way
provider drivers never have to deal with a struct clk pointer
unless they're using the clk consumer APIs.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 16:51:58 -07:00
Lee Jones d56f8994b6 clk: Provide OF helper to mark clocks as CRITICAL
This call matches clocks which have been marked as critical in DT
and sets the appropriate flag.  These flags can then be used to
mark the clock core flags appropriately prior to registration.

Legacy bindings requiring this feature must add the clock-critical
property to their binding descriptions, as it is not a part of
common-clock binding.

Cc: devicetree@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/1455225554-13267-4-git-send-email-mturquette@baylibre.com
2016-04-09 11:58:11 -07:00
Lee Jones 32b9b10961 clk: Allow clocks to be marked as CRITICAL
Critical clocks are those which must not be gated, else undefined
or catastrophic failure would occur.  Here we have chosen to
ensure the prepare/enable counts are correctly incremented, so as
not to confuse users with enabled clocks with no visible users.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/1455225554-13267-2-git-send-email-mturquette@baylibre.com
2016-04-09 11:58:10 -07:00
Stephen Boyd 929e7f3bc7 clk: Make of_clk_get_parent_count() return unsigned ints
Russell King recently pointed out a bug in the clk-gpio code
where it fails to register the clk if of_clk_get_parent_count()
returns an error because the "clocks" property isn't present in
the DT node. If we're trying to count parents from DT we'd like
to know the count, not if there is a "clocks" property or not.
Furthermore, some drivers are assigning the return value to their
clk_init_data::num_parents member which is unsigned, leading to
potentially large numbers of parents when the property isn't
present.

Let's change the API to return an unsigned int instead of an int.
All the callers just want to know the count anyway, and this
avoids the bug that was in the clk-gpio driver.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-26 16:01:32 -08:00
Stephen Boyd 1e42754eac clk: provider: Remove of_gpio_{gate,mux}_clk_setup() prototypes
These functions either never existed or were only used in
OF_CLK_DECLARE() macros. Remove the dead prototypes.

Cc: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-06 23:40:27 -08:00
Stephen Boyd 47b0eeb3dc clk: Deprecate CLK_IS_ROOT
We don't use CLK_IS_ROOT but in a few places in the common clk
framework core. Let's replace those checks with a check for the
number of parents a clk has instead of the flag, freeing up one
flag for something else. We don't remove the flag yet so that
things keep building, but we'll remove it once all drivers have
removed their flag usage.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-06 23:38:26 -08:00
Masahiro Yamada 0b225e41e3 clk: add clk_unregister_fixed_rate()
Allow to unregister fixed rate clock.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-01-29 16:37:24 -08:00
Masahiro Yamada cbf9591f66 clk: add clk_unregister_fixed_factor()
Allow to unregister fixed factor clock.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-01-29 16:35:49 -08:00
Geliang Tang 5fd9c05c84 clk: move the common clock's to_clk_*(_hw) macros to clk-provider.h
to_clk_*(_hw) macros have been repeatedly defined in many places.
This patch moves all the to_clk_*(_hw) definitions in the common
clock framework to public header clk-provider.h, and drop the local
definitions.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-01-29 12:59:50 -08:00
Heiko Stuebner 5035981979 clk-divider: make sure read-only dividers do not write to their register
Commit e6d5e7d90b ("clk-divider: Fix READ_ONLY when divider > 1") removed
the special ops struct for read-only clocks and instead opted to handle
them inside the regular ops.

On the rk3368 this results in breakage as aclkm now gets set a value.
While it is the same divider value, the A53 core still doesn't like it,
which can result in the cpu ending up in a hang.
The reason being that "ACLKENMasserts one clock cycle before the rising
edge of ACLKM" and the clock should only be touched when STANDBYWFIL2
is asserted.

To fix this, reintroduce the read-only ops but do include the round_rate
callback. That way no writes that may be unsafe are done to the divider
register in any case.

The Rockchip use of the clk_divider_ops is adapted to this split again,
as is the nxp, lpc18xx-ccu driver that was included since the original
commit. On lpc18xx-ccu the divider seems to always be read-only
so only uses the new ops now.

Fixes: e6d5e7d90b ("clk-divider: Fix READ_ONLY when divider > 1")
Reported-by: Zhang Qing <zhangqing@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-01-29 12:44:37 -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
Geert Uytterhoeven 20dd882a09 clk: Use static inline functions instead of macros for dummies
if CONFIG_OF=n:

    drivers/clk/clk-cs2000-cp.c: In function ‘cs2000_remove’:
    drivers/clk/clk-cs2000-cp.c:453:22: warning: unused variable ‘np’ [-Wunused-variable]
      struct device_node *np = dev->of_node;
			  ^

Convert dummies of_clk_del_provider() and of_clk_init() from macros to
static inline functions to kill such compiler warnings.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-11-20 11:16:31 -08:00
Masahiro Yamada 1971dfb7e8 clk: fix a typo in comment block of struct clk_rate_request
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-11-20 11:03:18 -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
Stephen Boyd 679c51cffc clk: Add stubs for of_clk_*() APIs when CONFIG_OF=n
Compiling the versatile clock driver with COMPILE_TEST=y and CONFIG_OF=n
leads to the following error:

   drivers/clk/versatile/clk-sp810.c: In function 'clk_sp810_of_setup':
   drivers/clk/versatile/clk-sp810.c:103:6: error: implicit declaration of
function 'of_clk_parent_fill' [-Werror=implicit-function-declaration]

Silence it by providing stubs APIs for of_clk_parent_fill().
Throw in a stub for of_clk_get_parent_count() too because we're
in the area.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-26 11:57:50 -07:00
Stephen Boyd acba7855dd clk: Remove clk_{register,unregister}_multiplier()
These APIs aren't used, so remove them. This can be reverted if
we get a user at some point.

Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Suggested-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-23 13:34:46 -07:00
Stephen Boyd 938ce30e29 Allwinner clock additions for 4.4
- Support for the Audio PLL and child clocks
   - Support for the A33 AHB gates
   - New clk-multiplier generic driver
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Merge tag 'sunxi-clocks-for-4.4' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux into clk-next

Pull Allwinner clock additions for 4.4 from Maxime Ripard:

  - Support for the Audio PLL and child clocks
  - Support for the A33 AHB gates
  - New clk-multiplier generic driver

* tag 'sunxi-clocks-for-4.4' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux:
  clk: sunxi: mod1 clock support
  clk: sunxi: codec clock support
  clk: sunxi: pll2: Add A13 support
  clk: sunxi: Add a driver for the PLL2
  clk: Add a basic multiplier clock
  clk: sunxi: Add A33 gates support
2015-10-21 16:29:03 -07:00
Maxime Ripard f2e0a53271 clk: Add a basic multiplier clock
Some clocks are using a multiplier component, however, unlike their mux,
gate or divider counterpart, these factors don't have a basic clock
implementation.

This leads to code duplication across platforms that want to use that kind
of clocks, and the impossibility to use the composite clocks with such a
clock without defining your own rate operations.

Create such a driver in order to remove these issues, and hopefully factor
the implementations, reducing code size across platforms and consolidating
the various implementations.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
2015-10-21 21:51:27 +02:00
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
Andy Shevchenko 934e2536b1 clk: fractional-divider: keep mwidth and nwidth internally
The patch adds mwidth and nwidth fields to the struct clk_fractional_divider
for further usage. While here, use GENMASK() instead of open coding this
functionality.

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-02 11:29:46 -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
Stephen Boyd 37bff2c159 clk: gpio: Mark parent_names array const
Let's encourage const arrays of parent names like other basic
clock types.

Cc: Sergej Sawazki <ce3a@gmx.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-28 11:59:24 -07:00
Jim Quinlan afe76c8fd0 clk: allow a clk divider with max divisor when zero
This commit allows certain Broadcom STB clock dividers to be used with
clk-divider.c.  It allows for a clock whose field value is the equal
to the divisor, execpt when the field value is zero, in which case the
divisor is 2^width.  For example, consider a divisor clock with a two
bit field:

value		divisor
0		4
1		1
2		2
3		3

Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
2015-07-28 11:59:19 -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 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 61ae76563e clk: Remove clk.h from clk-provider.h
Remove clk.h from clk-provider.h so that we can clearly split clk
providers from clk consumers. This will allow us to quickly
detect when clock providers are using the consumer APIs by
looking at the includes.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-20 11:11:42 -07:00
Sergej Sawazki 80eeb1f0f7 clk: add gpio controlled clock multiplexer
Add a common clock driver for basic gpio controlled clock multiplexers.
This driver can be used for devices like 5V41068A or 831721I from IDT
or for discrete multiplexer circuits. The 'select' pin selects one of
two parent clocks.

Cc: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Sergej Sawazki <ce3a@gmx.de>
[sboyd@codeaurora.org: Fix error paths to free memory and do it
in the correct order]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-06 17:20:52 -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
Daniel Thompson 3037e9ea78 clk: fixed: Add comment to clk_fixed_set_rate
Currently it is not made explicit why clk_fixed_set_rate() can ignore
its arguments and unconditionally return success. Add a comment
to explain this.

We also mark the clk_ops table const since it should never be
modified at runtime.

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-06-10 14:19:43 -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
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
Sascha Hauer 2893c37946 clk: make strings in parent name arrays const
The clk functions and structs declare the parent_name arrays as
'const char **parent_names' which means the parent name strings
are const, but the array itself is not. Use
'const char * const * parent_names' instead which also makes
the array const. This allows us to put the parent_name arrays into
the __initconst section.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[sboyd@codeaurora.org: Squelch 80-character checkpatch warnings]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-05-05 22:50:03 -07:00
Martin Fuzzey 820ad9752c clk: clk-gpio-gate: Fix active low
The active low flag in the DT cell is currently ignored.

This occurs because of_get_named_gpio_flags() does not apply the flags
to the underlying struct gpio_desc so the test in clk_register_gpio_gate()
was bogus.

Note that this patch changes the internal kernel API for
clk_register_gpio_gate() but there are currently no other users.

Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Acked-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-04-10 17:45:30 -07:00
Javier Martinez Canillas 2e65d8bfe8 clk: Add __clk_hw_set_clk helper function
After the clk API change to return a per-user clock instance, both the
struct clk_core and struct clk pointers from the hw clock needs to be
assigned to clock that share the same state.

In the future the struct clk_core will be removed and this is going to
change again so to avoid having to change the assignments twice in all
the drivers, add a helper function to have an indirection level.

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 09:40:07 -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
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
Stephen Boyd bca9690b94 clk: divider: Make generic for usage elsewhere
Some devices don't use mmio to interact with dividers. Split out the
logic from the register read/write parts so that we can reuse the
division logic elsewhere.

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 11:48:52 -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
Krzysztof Kozlowski 4e3c021fb9 clk: Add clk_unregister_{divider, gate, mux} to close memory leak
The common clk_register_{divider,gate,mux} functions allocated memory
for internal data which wasn't freed anywhere. Drivers using these
helpers could only unregister clocks but the memory would still leak.

Add corresponding unregister functions which will release all resources.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-17 13:52:41 -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 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
James Hogan e6d5e7d90b clk-divider: Fix READ_ONLY when divider > 1
Commit 79c6ab5095 (clk: divider: add CLK_DIVIDER_READ_ONLY flag) in
v3.16 introduced the CLK_DIVIDER_READ_ONLY flag which caused the
recalc_rate() and round_rate() clock callbacks to be omitted.

However using this flag has the unfortunate side effect of causing the
clock recalculation code when a clock rate change is attempted to always
treat it as a pass-through clock, i.e. with a fixed divide of 1, which
may not be the case. Child clock rates are then recalculated using the
wrong parent rate.

Therefore instead of dropping the recalc_rate() and round_rate()
callbacks, alter clk_divider_bestdiv() to always report the current
divider as the best divider so that it is never altered.

For me the read only clock was the system clock, which divided the PLL
rate by 2, from which both the UART and the SPI clocks were divided.
Initial setting of the UART rate set it correctly, but when the SPI
clock was set, the other child clocks were miscalculated. The UART clock
was recalculated using the PLL rate as the parent rate, resulting in a
UART new_rate of double what it should be, and a UART which spewed forth
garbage when the rate changes were propagated.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Thomas Abraham <thomas.ab@samsung.com>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Max Schwarz <max.schwarz@online.de>
Cc: <stable@vger.kernel.org> # v3.16+
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2014-11-17 11:13:52 -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
Maxime Ripard 355bb165cd clk: Include of.h in clock-provider.h
CLK_OF_DECLARE relies on OF_DECLARE_1 that is defined in of.h. Fixes build
errors when one use CLK_OF_DECLARE but doesn't include of.h

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
2014-09-27 08:57:50 +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
Jyri Sarha c873d14d30 clk: add gpio gated clock
The added gpio-gate-clock is a basic clock that can be enabled and
disabled trough a gpio output. The DT binding document for the clock
is also added. For EPROBE_DEFER handling the registering of the clock
has to be delayed until of_clk_get() call time.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-26 16:51:42 -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
Linus Torvalds 1a5700bc2d The clock framework changes for 3.16 are pretty typical: mostly clock
driver additions and fixes. There are additions to the clock core code
 for some of the basic types (e.g. the common divider type has some fixes
 and featured added to it).
 
 One minor annoyance is a last-minute dependency that wasn't handled
 quite right. ba0fae3 in this pull request depends on
 include/dt-bindings/clock/berlin2.h, which is already in your tree via
 the arm-soc pull request. Building for the berlin platform will break
 when the clk tree is built on it's own, but merged into your master
 branch everything should be fine.
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Merge tag 'clk-for-linus-3.16' of git://git.linaro.org/people/mike.turquette/linux into next

Pull clock framework updates from Mike Turquette:
 "The clock framework changes for 3.16 are pretty typical: mostly clock
  driver additions and fixes.  There are additions to the clock core
  code for some of the basic types (e.g. the common divider type has
  some fixes and featured added to it).

  One minor annoyance is a last-minute dependency that wasn't handled
  quite right.  Commit ba0fae3b06 ("clk: berlin: add core clock driver
  for BG2/BG2CD") in this pull request depends on
  include/dt-bindings/clock/berlin2.h, which is already in your tree via
  the arm-soc pull request.  Building for the berlin platform will break
  when the clk tree is built on it's own, but merged into your master
  branch everything should be fine"

* tag 'clk-for-linus-3.16' of git://git.linaro.org/people/mike.turquette/linux: (75 commits)
  mmc: sunxi: Add driver for SD/MMC hosts found on Allwinner sunxi SoCs
  clk: export __clk_round_rate for providers
  clk: versatile: free icst on error return
  clk: qcom: Return error pointers for unimplemented clocks
  clk: qcom: Support msm8974pro global clock control hardware
  clk: qcom: Properly support display clocks on msm8974
  clk: qcom: Support display RCG clocks
  clk: qcom: Return highest rate when round_rate() exceeds plan
  clk: qcom: Fix mmcc-8974's PLL configurations
  clk: qcom: Fix clk_rcg2_is_enabled() check
  clk: berlin: add core clock driver for BG2Q
  clk: berlin: add core clock driver for BG2/BG2CD
  clk: berlin: add driver for BG2x complex divider cells
  clk: berlin: add driver for BG2x simple PLLs
  clk: berlin: add driver for BG2x audio/video PLL
  clk: st: Terminate of match table
  clk/exynos4: Fix compilation warning
  ARM: shmobile: r8a7779: Add clock index macros for DT sources
  clk: divider: Fix overflow in clk_divider_bestdiv
  clk: u300: Terminate of match table
  ...
2014-06-07 20:27:30 -07:00
Linus Torvalds d27050641e DeviceTree for 3.16:
- Another round of clean-up of FDT related code in architecture code.
   This removes knowledge of internal FDT details from most architectures
   except powerpc.
 - Conversion of kernel's custom FDT parsing code to use libfdt.
 - DT based initialization for generic serial earlycon. The introduction
   of generic serial earlycon support went in thru tty tree.
 - Improve the platform device naming for DT probed devices to ensure
   unique naming and use parent names instead of a global index.
 - Fix a race condition in of_update_property.
 - Unify the various linker section OF match tables and fix several
   function prototype errors.
 - Update platform_get_irq_byname to work in deferred probe cases.
 - 2 binding doc updates
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Merge tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux into next

Pull DeviceTree updates from Rob Herring:
 - Another round of clean-up of FDT related code in architecture code.
   This removes knowledge of internal FDT details from most
   architectures except powerpc.
 - Conversion of kernel's custom FDT parsing code to use libfdt.
 - DT based initialization for generic serial earlycon.  The
   introduction of generic serial earlycon support went in through the
   tty tree.
 - Improve the platform device naming for DT probed devices to ensure
   unique naming and use parent names instead of a global index.
 - Fix a race condition in of_update_property.
 - Unify the various linker section OF match tables and fix several
   function prototype errors.
 - Update platform_get_irq_byname to work in deferred probe cases.
 - 2 binding doc updates

* tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (58 commits)
  of: handle NULL node in next_child iterators
  of/irq: provide more wrappers for !CONFIG_OF
  devicetree: bindings: Document micrel vendor prefix
  dt: bindings: dwc2: fix required value for the phy-names property
  of_pci_irq: kill useless variable in of_irq_parse_pci()
  of/irq: do irq resolution in platform_get_irq_byname()
  of: Add a testcase for of_find_node_by_path()
  of: Make of_find_node_by_path() handle /aliases
  of: Create unlocked version of for_each_child_of_node()
  lib: add glibc style strchrnul() variant
  of: Handle memory@0 node on PPC32 only
  pci/of: Remove dead code
  of: fix race between search and remove in of_update_property()
  of: Use NULL for pointers
  of: Stop naming platform_device using dcr address
  of: Ensure unique names without sacrificing determinism
  tty/serial: pl011: add DT based earlycon support
  of/fdt: add FDT serial scanning for earlycon
  of/fdt: add FDT address translation support
  serial: earlycon: add DT support
  ...
2014-06-04 10:02:38 -07:00
Heiko Stuebner 79c6ab5095 clk: divider: add CLK_DIVIDER_READ_ONLY flag
From: Heiko Stuebner <heiko@sntech.de>

Similar to muxes which already have a read-only flag there sometimes
exist dividers which should not be changed by the clock framework
but whose value still should be readable.

Therefore add a READ_ONLY flag similar to the mux-one to clk-divider

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
[changed flag bit to BIT(5) as suggested by Tomasz Figa]
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Acked-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Max Schwarz <max.schwarz@online.de>
Tested-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-05-23 13:45:47 -07:00
Rob Herring 54196ccbe0 of: consolidate linker section OF match table declarations
We now have several OF match tables using linker sections that are
nearly the same definition. The only variation is the callback function
prototype. Create a common define for creating linker section OF match
table entries which each table declaration can use.

Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
2014-05-20 14:25:24 -05:00
Heikki Krogerus e2d0e90fae clk: new basic clk type for fractional divider
Fractional divider clocks are fairly common. This adds basic
type for them.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-20 13:34:02 +02:00
Geert Uytterhoeven 54e73016dd clk: Improve clk_ops documentation
General:
  - Add parameter names to .round_rate() and .set_rate().

Documentation/clk.txt:
  - Add missing parameter for .set_rate(),
  - Add missing .debug_init().

include/linux/clk-provider.h:
  - Add parent rate documentation for .round_rate(),
  - Reorder documentation to match implementation order,
  - Add missing documentation for .init().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-05-12 17:08:33 -07:00
Geert Uytterhoeven 725b418b43 clk: Fixup spacing in comments
- Remove spaces in front of TABs,
- Correct indentation for some CLK_* flag descriptions.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-05-12 17:08:33 -07:00
Maxime COQUELIN 774b514390 clk: divider: Add round to closest divider
In some cases, we want to be able to round the divider to the closest one,
instead than rounding up.

This patch adds a new CLK_DIVIDER_ROUND_CLOSEST flag to specify the divider
has to round to closest div, keeping rounding up as de default behaviour.

Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-04-30 11:51:26 -07:00
Alex Elder c646cbf10f clk: support hardware-specific debugfs entries
Add a new clk_ops->debug_init method to allow a clock hardware
driver to populate the clock's debugfs directory with entries
beyond those common for every clock.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-03-24 17:10:07 -07:00
Linus Torvalds 4bcec913d0 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull more powerpc bits from Ben Herrenschmidt:
 "Here are a few more powerpc bits for this merge window.  The bulk is
  made of two pull requests from Scott and Anatolij that I had missed
  previously (they arrived while I was away).  Since both their branches
  are in -next independently, and the content has been around for a
  little while, they can still go in.

  The rest is mostly bug and regression fixes, a small series of
  cleanups to our pseries cpuidle code (including moving it to the right
  place), and one new cpuidle bakend for the powernv platform.  I also
  wired up the new sched_attr syscalls"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (37 commits)
  powerpc: Wire up sched_setattr and sched_getattr syscalls
  powerpc/hugetlb: Replace __get_cpu_var with get_cpu_var
  powerpc: Make sure "cache" directory is removed when offlining cpu
  powerpc/mm: Fix mmap errno when MAP_FIXED is set and mapping exceeds the allowed address space
  powerpc/powernv/cpuidle: Back-end cpuidle driver for powernv platform.
  powerpc/pseries/cpuidle: smt-snooze-delay cleanup.
  powerpc/pseries/cpuidle: Remove MAX_IDLE_STATE macro.
  powerpc/pseries/cpuidle: Make cpuidle-pseries backend driver a non-module.
  powerpc/pseries/cpuidle: Use cpuidle_register() for initialisation.
  powerpc/pseries/cpuidle: Move processor_idle.c to drivers/cpuidle.
  powerpc: Fix 32-bit frames for signals delivered when transactional
  powerpc/iommu: Fix initialisation of DART iommu table
  powerpc/numa: Fix decimal permissions
  powerpc/mm: Fix compile error of pgtable-ppc64.h
  powerpc: Fix hw breakpoints on !HAVE_HW_BREAKPOINT configurations
  clk: corenet: Adds the clock binding
  powerpc/booke64: Guard e6500 tlb handler with CONFIG_PPC_FSL_BOOK3E
  powerpc/512x: dts: add MPC5125 clock specs
  powerpc/512x: clk: support MPC5121/5123/5125 SoC variants
  powerpc/512x: clk: enforce even SDHC divider values
  ...
2014-01-30 17:07:18 -08:00
Benjamin Herrenschmidt e9a371100d Merge remote-tracking branch 'agust/next' into next
<<
Switch mpc512x to the common clock framework and adapt mpc512x
drivers to use the new clock driver. Old PPC_CLOCK code is
removed entirely since there are no users any more.
>>
2014-01-29 16:53:55 +11:00
Tero Kristo 819b4861c1 CLK: ti: add init support for clock IP blocks
ti_dt_clk_init_provider() can now be used to initialize the contents of
a single clock IP block. This parses all the clocks under the IP block
and calls the corresponding init function for them.

This patch also introduces a helper function for the TI clock drivers
to get register info from DT and append the master IP info to this.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-01-17 12:34:52 -08:00
Stephen Boyd 3fa2252b7a clk: Add set_rate_and_parent() op
Some of Qualcomm's clocks can change their parent and rate at the
same time with a single register write. Add support for this
hardware to the common clock framework by adding a new
set_rate_and_parent() op. When the clock framework determines
that both the parent and the rate are going to change during
clk_set_rate() it will call the .set_rate_and_parent() op if
available and fall back to calling .set_parent() followed by
.set_rate() otherwise.

Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-01-16 12:00:57 -08:00
Gerhard Sittig 6d8cdb6824 clk: mpc512x: introduce COMMON_CLK for MPC512x (disabled)
this change implements a clock driver for the MPC512x PowerPC platform
which follows the COMMON_CLK approach and uses common clock drivers
shared with other platforms

this driver implements the publicly announced set of clocks (those
listed in the dt-bindings header file), as well as generates additional
'struct clk' items where the SoC hardware cannot easily get mapped to
the common primitives (shared code) of the clock API, or requires
"intermediate clock nodes" to represent clocks that have both gates and
dividers

the previous PPC_CLOCK implementation is kept in place and remains
active for the moment, the newly introduced CCF clock driver will
receive additional support for backwards compatibility in a subsequent
patch before it gets enabled and will replace the PPC_CLOCK approach

some of the clock items get pre-enabled in the clock driver to not have
them automatically disabled by the underlying clock subsystem because of
their being unused -- this approach is desirable because
- some of the clocks are useful to have for diagnostics and information
  despite their not getting claimed by any drivers (CPU, internal and
  external RAM, internal busses, boot media)
- some of the clocks aren't claimed by their peripheral drivers yet,
  either because of missing driver support or because device tree specs
  aren't available yet (but the workarounds will get removed as the
  drivers get adjusted and the device tree provides the clock specs)

clkdev registration provides "alias names" for few clock items
- to not break those peripheral drivers which encode their component
  index into the name that is used for clock lookup (UART, SPI, USB)
- to not break those drivers which use names for the clock lookup which
  were encoded in the previous PPC_CLOCK implementation (NFC, VIU, CAN)
this workaround will get removed as these drivers get adjusted after
device tree based clock lookup has become available

the COMMON_CLK implementation copes with device trees which lack an
oscillator node (backwards compat), the REF clock is then derived from
the IPS bus frequency and multiplier values fetched from hardware

Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
2014-01-12 18:53:03 +01:00
Boris BREZILLON 0903ea6017 clk: add accuracy support for fixed clock
This patch adds support for accuracy retrieval on fixed clocks.
It also adds a new dt property called 'clock-accuracy' to define the clock
accuracy.

This can be usefull for oscillator (RC, crystal, ...) definitions which are
always given an accuracy characteristic.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-12-22 23:14:28 -08:00
Boris BREZILLON 5279fc402a clk: add clk accuracy retrieval support
The clock accuracy is expressed in ppb (parts per billion) and represents
the possible clock drift.
Say you have a clock (e.g. an oscillator) which provides a fixed clock of
20MHz with an accuracy of +- 20Hz. This accuracy expressed in ppb is
20Hz/20MHz = 1000 ppb (or 1 ppm).

Clock users may need the clock accuracy information in order to choose
the best clock (the one with the best accuracy) across several available
clocks.

This patch adds clk accuracy retrieval support for common clk framework by
means of a new function called clk_get_accuracy.
This function returns the given clock accuracy expressed in ppb.

In order to get the clock accuracy, this implementation adds one callback
called recalc_accuracy to the clk_ops structure.
This callback is given the parent clock accuracy (if the clock is not a
root clock) and should recalculate the given clock accuracy.

This callback is optional and may be implemented if the clock is not
a perfect clock (accuracy != 0 ppb).

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-12-22 23:14:27 -08:00
Mike Turquette f61027426a clk: of: helper for determining number of parent clocks
Walks the "clocks" array of parent clock phandles and returns the
number.

Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-10-07 23:13:33 -07:00
Gerhard Sittig aa514ce34b clk: wrap I/O access for improved portability
the common clock drivers were motivated/initiated by ARM development
and apparently assume little endian peripherals

wrap register/peripherals access in the common code (div, gate, mux)
in preparation of adding COMMON_CLK support for other platforms

Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-08-27 17:50:38 -07:00
James Hogan e366fdd725 clk: clk-mux: implement remuxing on set_rate
Implement clk-mux remuxing if the CLK_SET_RATE_NO_REPARENT flag isn't
set. This implements determine_rate for clk-mux to propagate to each
parent and to choose the best one (like clk-divider this chooses the
parent which provides the fastest rate <= the requested rate).

The determine_rate op is implemented as a core helper function so that
it can be easily used by more complex clocks which incorporate muxes.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-08-19 12:27:18 -07:00
James Hogan 819c1de344 clk: add CLK_SET_RATE_NO_REPARENT flag
Add a CLK_SET_RATE_NO_REPARENT clock flag, which will prevent muxes
being reparented during clk_set_rate.

To avoid breaking existing platforms, all callers of clk_register_mux()
are adjusted to pass the new flag. Platform maintainers are encouraged
to remove the flag if they wish to allow mux reparenting on set_rate.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Viresh Kumar <viresh.linux@gmail.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Haojian Zhuang <haojian.zhuang@linaro.org>
Cc: Chao Xie <xiechao.mail@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Emilio López" <emilio@elopez.com.ar>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Prashant Gaikwad <pgaikwad@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Peter De Schrijver <pdeschrijver@nvidia.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrew Chew <achew@nvidia.com>
Cc: Doug Anderson <dianders@chromium.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Paul Walmsley <pwalmsley@nvidia.com>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Thomas Abraham <thomas.abraham@linaro.org>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: spear-devel@list.st.com
Cc: linux-tegra@vger.kernel.org
Tested-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Acked-by: Stephen Warren <swarren@nvidia.com> [tegra]
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> [sunxi]
Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com> [Zynq]
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-08-19 12:27:17 -07:00
James Hogan 71472c0c06 clk: add support for clock reparent on set_rate
Add core support to allow clock implementations to select the best
parent clock when rounding a rate, e.g. the one which can provide the
closest clock rate to that requested. This is by way of adding a new
clock op, determine_rate(), which is like round_rate() but has an extra
parameter to allow the clock implementation to optionally select a
different parent clock. The core then takes care of reparenting the
clock when setting the rate.

The parent change takes place with the help of some new private data
members. struct clk::new_parent specifies a clock's new parent (NULL
indicates no change), and struct clk::new_child specifies a clock's new
child (whose new_parent member points back to it). The purpose of these
are to allow correct walking of the future tree for notifications prior
to actually reparenting any clocks, specifically to skip child clocks
who are being reparented to another clock (they will be notified via the
new parent), and to include any new child clock. These pointers are set
by clk_calc_subtree(), and the new_child pointer gets cleared when a
child is actually reparented to avoid duplicate POST_RATE_CHANGE
notifications.

Each place where round_rate() is called, determine_rate() is checked
first and called in preference. This restructures a few of the call
sites to simplify the logic into if/else blocks.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-08-19 12:27:17 -07:00