Commit Graph

38 Commits

Author SHA1 Message Date
Elaine Zhang 956060a527 clk: rockchip: add support for half divider
The new Rockchip socs have optional half divider:
The formula is shown as:
	freq_out = 2*freq_in / (2*div + 3)
Is this the same for all of new SoCs.

So we use "branch_half_divider" + "COMPOSITE_NOMUX_HALFDIV \
DIV_HALF \ COMPOSITE_HALFDIV \ CMPOSITE_NOGATE_HALFDIV"
to hook that special divider clock-type into our clock-tree.

Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2018-07-06 19:17:57 +02:00
Yisheng Xie a425702f68 clk: rockchip: use match_string() helper
match_string() returns the index of an array for a matching string,
which can be used intead of open coded variant.

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: linux-clk@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-rockchip@lists.infradead.org
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2018-05-22 13:32:09 +02:00
Shawn Lin fd3cbbfb76 clk: rockchip: Free the memory on the error path
rockchip_clk_register_branch() and rockchip_clk_register_frac_branch()
should free the memory internally when seeing any failure.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2018-03-02 08:51:03 +01:00
Stephen Boyd 1dfcfa721f clk: rockchip: Mark rockchip_fractional_approximation static
Silence the sparse warning

clk/rockchip/clk.c:172:6: warning: symbol 'rockchip_fractional_approximation' was not declared. Should it be static?

Cc: Elaine Zhang <zhangqing@rock-chips.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2017-08-23 15:35:41 -07:00
Elaine Zhang 5d890c2df9 clk: rockchip: add special approximation to fix up fractional clk's jitter
>From Rockchips fractional divider description:
  3.1.9  Fractional divider usage
  To get specific frequency, clocks of I2S, SPDIF, UARTcan be generated by
  fractional divider. Generally you must set that denominator is 20 times
  larger than numerator to generate precise clock frequency. So the
  fractional divider applies only to generate low frequency clock like
  I2S, UART.

Therefore add a special approximation function that handles this
special requirement.

Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2017-08-08 17:45:42 +02:00
Douglas Anderson 8118fe40d4 clk: rockchip: Remove useless init of "grf" to -EPROBE_DEFER
When we used to defer setting the "grf" member to
rockchip_clk_get_grf() it was important to init the "grf" member to an
error value in rockchip_clk_init().  With recent changes, we now set
"grf" right in rockchip_clk_init() (two lines below the place where we
initted it).  That makes the old init useless.  Get rid of it.

Fixes: 6f339dc271 ("clk: rockchip: lookup General Register Files in rockchip_clk_init")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2017-01-06 18:08:16 +01:00
Heiko Stuebner cb1d9f6dda clk: rockchip: add a clock-type for muxes based in the grf
Rockchip socs often have some tiny number of muxes not controlled from
the core clock controller but through bits set in the general register
files. Add a clock-type that can control these as well, so that we
don't need to work around them being absent.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2017-01-02 14:24:57 +01:00
Lin Huang a4f182bf81 clk: rockchip: add new clock-type for the ddrclk
Changing the rate of the DDR clock needs special care, as the DDR
is of course in use and will react badly if the rate changes under it.

Over time different approaches to handle that were used.

Past SoCs like the rk3288 and before would store some code in SRAM
while the rk3368 used a SCPI variant and let a coprocessor handle that.

New rockchip platforms like the rk3399 have a dcf controller to do ddr
frequency scaling, and support for this controller will be implemented
in the arm-trusted-firmware.

This new clock-type should over time handle all these methods for
handling DDR rate changes, but right now it will concentrate on the
SIP interface used to talk to ARM trusted firmware.

The SIP interface counterpart was merged from pull-request #684 [0]
into the upstream arm-trusted-firmware codebase.

[0] https://github.com/ARM-software/arm-trusted-firmware/pull/684

Signed-off-by: Lin Huang <hl@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-09-01 11:23:56 +02:00
Heiko Stübner e6cebc7273 clk: rockchip: use general clock flag when registering pll
Add the general flags the pll list already contains to the clock init,
so that needed clock flags can be used for plls.

Signed-off-by: Heiko Stübner <heiko@sntech.de>
2016-08-08 10:57:21 +02:00
Heiko Stuebner c9c3c6eecc clk: rockchip: simplify GRF handling in pll clocks
With the previous commit, the clock drivers now know at init time if the
GRF regmap is available. That means if it isn't available then, it also
won't become available later and we can therefore switch PLLs, that need
the GRF for the lock-status, to read-only mode - similar behaviour as the
aborting of rate changes we did before.

This saves some conditionals on every rate change and we can also drop
the rockchip_clk_get_grf function completely.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-05-09 16:04:15 +02:00
Heiko Stuebner 6f339dc271 clk: rockchip: lookup General Register Files in rockchip_clk_init
In the distant past syscons were initialized pretty late and weren't
available at the time the clock init ran. As the GRF is mainly needed
for PLL lock-status checking, we had this lazy init that tried to grab
the syscon on PLL rate changes and denied these changes if it was not
available.

These days syscons are available very early and recent addition to
rockchip clocks, like the PLL clk_init actually also rely on them
being available at that time, so there is no need to keep that lazy
init around, as it will also result in some more simplifications in
other parts of the clock-code.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-05-09 16:04:11 +02:00
Heiko Stuebner 03ae174786 clk: rockchip: fix checkpatch warning in core code
We seem to have accumulated a bunch of checkpatch warnings, with mainly
overlong lines and two unnecessary allocation error messages.
Most were introduced with the recent multi-controller-support but some
were quite a bit older.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-04-20 09:53:39 +02:00
Shawn Lin ff1ae20961 clk: rockchip: remove redundant checking of device_node
rockchip_clk_of_add_provider is used by sub-clk driver which
already call of_iomap before calling it. If device_node does
not exist, of_iomap returns NULL which will fail to init the
sub-clk driver. So really it's redundant.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-03-27 13:03:35 +02:00
Xing Zheng ef1d9feecc clk: rockchip: Add support for multiple clock providers
There are need to support Multi-CRUs probability in future, but
it is not supported on the current Rockchip Clock Framework.

Therefore, this patch add support a provider as the parameter
handler when we call the clock register functions for per CRU.

Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-03-27 13:03:34 +02:00
Michael Turquette 70750ff2c9 Introduction of a factor type and a variant containing a gate
to be able to also declare factor clocks in their correct
 place in the clock tree instead of having to register factor
 clocks in the init callback separately. And as always some more
 clock-ids and non-regression fixes for mistakes introduced in
 past kernel releases.
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Merge tag 'v4.6-rockchip-clk1' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip into clk-next

Introduction of a factor type and a variant containing a gate
to be able to also declare factor clocks in their correct
place in the clock tree instead of having to register factor
clocks in the init callback separately. And as always some more
clock-ids and non-regression fixes for mistakes introduced in
past kernel releases.
2016-02-15 11:59:45 -08:00
Heiko Stuebner 29a30c269a clk: rockchip: add a factor clock type
Add a clock type for fixed factor clocks. This allows us to define fixed
factor clocks where they appear in the clock hierarchy instead of in the
init function.

The additional factor_gate type, finally allows us to model some last
parts of the clock tree correctly.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-02-04 15:49:09 +01:00
Shawn Lin 2467b6745e clk: rockchip: free memory in error cases when registering clock branches
Add free memeory if rockchip_clk_register_branch fails.

Fixes: a245fecbb8 ("clk: rockchip: add basic infrastructure...")
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-02-02 22:09:50 +01:00
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 8ca1ca8f60 clk: rockchip: handle mux dependency of fractional dividers
The fractional dividers of Rockchip SoCs contain an "auto-gating-feature"
that requires the downstream mux to actually point to the fractional
divider and the fractional divider gate to be enabled, for it to really
accept changes to the divider ratio.

The downstream muxes themselfs are not generic enough to include them
directly into the fractional divider, as they have varying sources of
parent clocks including not only clocks related to the fractional
dividers but other clocks as well.

To solve this, allow our clock branches to specify direct child clock-
branches in the new child property, let the fractional divider register
its downstream mux through this and add a clock notifier that temporarily
switches the mux setting when it notices rate changes to the fractional
divider.

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 12:57:29 -08:00
Heiko Stuebner dfff24bde7 clk: rockchip: only enter pll slow-mode directly before reboots on rk3288
As commit 1d33929e2a ("clk: rockchip: switch PLLs to slow mode before
reboot for rk3288") states, switching the PLLs to slow-mode is only
necessary when rebooting using the soft-reset done through the CRU.

The dwc2 controllers used create really big number of interrupts in
special constellations involving usb-hubs and their number is so high,
it can even overwhelm the interrupt handler if the cpu-speed os to low.

Right now the PLLs are put into slow-mode in a shutdown syscore_ops
callback which means it happens on all reboots (not only the soft-reset
ones) and even on poweroff actions.

This can result in the system not powering off and getting stuck instead,
so we should move the slow-mode change nearer to the actual reboot action.

For this we introduce the possiblity to also set a callback that gets
called from the restart-handler directly prior to restarting the system
and move the shutdown-callback to this new option.

With this the slow-mode switch is done only on the necessary reboots
and also has a smaller possibility of causing artifacts.

Fixes: 1d33929e2a ("clk: rockchip: switch PLLs to slow mode before reboot for rk3288")
Signed-off-by: Heiko Stuebner <heiko.stuebner@collabora.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
2015-12-21 02:01:19 +01:00
Andy Shevchenko 5d49a6e103 clk: rockchip: save width in struct clk_fractional_divider
The ->mwidth and ->nwidth fields will be used by clk-fractional-divider when it
will be switched to rational base approximation algorithm.

Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-10-02 11:29:47 -07:00
Heiko Stuebner 8a76f443a9 clk: rockchip: add support for phase inverters
Most Rockchip socs have optional phase inverters connected to some
clocks that move the clock-phase by 180 degrees.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
[sboyd@codeaurora.org: Dropped lazy part of commit text]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-07-06 15:04:40 -07:00
Uwe Kleine-König 4a1caed3d0 clk: make several parent names const
Since commit 2893c37946 ("clk: make strings in parent name arrays
const") the name of parent clocks can be const. So add more const in
several clock drivers.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-06-04 14:27:06 -07:00
Uwe Kleine-König 692d8328e8 clk: don't use __initconst for non-const arrays
The statement

	static const char *name[];

defines a modifiable array of pointers to constant chars. That is

	*name[0] = 'f';

is forbidden, but

	name[0] = "f";

is not. So marking an array that is defined as above with __initconst is
wrong. Either an additional const must be added such that the whole
definition reads:

	static const char *const name[] __initconst;

or where this is not possible __initdata must be used.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-04-12 17:18:27 -07:00
Michael Turquette b572b5f821 - clock phase setting capability for the rk3288 mmc clocks
- pll init to allow syncing to actual rate table values
 - some more exported clocks
 - fixes for some clocks (typos etc) all of them not yet used
   in actual drivers
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Merge tag 'v3.19-rockchip-clk2' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip into clk-next

- clock phase setting capability for the rk3288 mmc clocks
- pll init to allow syncing to actual rate table values
- some more exported clocks
- fixes for some clocks (typos etc) all of them not yet used
  in actual drivers
2014-11-28 21:00:16 -08:00
Alexandru M Stan 89bf26cbc1 clk: rockchip: Add support for the mmc clock phases using the framework
This patch adds the 2 physical clocks for the mmc (drive and sample). They're
mostly there for the phase properties, but they also show the true clock
(by dividing by RK3288_MMC_CLKGEN_DIV).

The drive and sample phases are generated by dividing an upstream parent clock
by 2, this allows us to adjust the phase by 90 deg.

There's also an option to have up to 255 delay elements (40-80 picoseconds long).
This driver uses those elements (under the assumption that they're 60 ps long)
to generate approximate 22.5 degrees options. 67.5 (22.5*3) might be as high as
90 deg if the delay elements are as big as 80 ps, so a finer division (smaller
than 22.5) was not picked because the phase might not be monotonic anymore.

Suggested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Alexandru M Stan <amstan@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2014-11-28 00:44:24 +01:00
Heiko Stuebner 4f8a7c549f clk: rockchip: add ability to specify pll-specific flags
This adds a flag parameter to plls that allows us to create
special flags to tweak the behaviour of the plls if necessary.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Tested-by: Kever Yang <kever.yang@rock-chips.com>
2014-11-25 09:57:07 +01:00
Michael Turquette da57b46010 Merge branch 'clk-fixes' into clk-next 2014-11-24 17:45:33 -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
Kever Yang 78eaf6095c clk: rockchip: disable unused clocks
The rockchip clock driver use CLK_IGNORE_UNUSED flag to make sure
all the clocks are available like default power on state.
We have implement the clock manage in most of rockchip drivers,
it is time to remove it for power save.
Instead we add CLK_IGNORE_UNUSED for some clock nodes which should
be on during boot or no module driver in kernel will initialize it.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2014-11-04 22:52:51 +01:00
Heiko Stübner 6f1294b5a8 clk: rockchip: add restart handler
Add infrastructure to write the correct value to the restart register and
register the restart notifier for both rk3188 (including rk3066) and rk3288.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2014-10-01 14:11:42 +02:00
Heiko Stuebner f6fba5f696 clk: rockchip: add new clock-type for the cpuclk
When changing the armclk on Rockchip SoCs it is supposed to be reparented
to an alternate parent before changing the underlying pll and back after
the change. Additionally there exist clocks that are very tightly bound to
the armclk whose divider values are set according to the armclk rate.

Add a special clock-type to handle all that. The rate table and divider
values will be supplied from the soc-specific clock controllers.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Doug Anderson <dianders@chromium.org>
On a rk3288-board:
Tested-by: Doug Anderson <dianders@chromium.org>
2014-09-27 17:57:41 +02:00
Heiko Stübner fe94f974e9 clk: rockchip: protect critical clocks from getting disabled
The clock-tree contains clocks that should never get disabled automatically.
One example are the base ACLKs, the base supplies for all peripherals.

Therefore add a structure similar to the sunxi clock-tree to protect these
special clocks from being disabled.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Doug Anderson <dianders@chromium.org>
Tested-by: Kever Yang <kever.yang@rock-chips.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-02 15:03:18 -07:00
Heiko Stübner 1a4b181995 clk: rockchip: make rockchip_clk_register_branch static
It is only used locally in clk/rockchip/clk.c and thus can be static.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-02 15:03:17 -07:00
Heiko Stübner b2155a71a7 clk: rockchip: implement the fraction divider branch type
Rockchip SoCs may provide fraction dividers for some clocks, mostly for
i2s and uarts. In contrast to the other registers, these do not use
the hiword-mask paradigm, but instead split the register into the upper
16 bit for the nominator and the lower 16 bit for the denominator.

The common clock framework got a generic fractional divider clock type
recently that can accomodate this setting easily. All currently known
fraction dividers have a separate gate too, therefore implement the
divider as composite using the ops-struct from fractional_divider clock
and add the gate if necessary.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-02 15:03:17 -07:00
Heiko Stübner 90c5902540 clk: rockchip: add clock type for pll clocks and pll used on rk3066
All known Rockchip SoCs down to the RK28xx (ARM9) use a similar pattern to
handle their plls:
                       |--\
xin32k ----------------|mux\
xin24m -----| pll |----|pll|--- pll output
       \---------------|src/
                       |--/

The pll output is sourced from 1 of 3 sources, the actual pll being one of
them. To change the pll frequency it is imperative to remux it to another
source beforehand. This is done by adding a clock-listener to the pll that
handles the remuxing before and after the rate change.

The output mux is implemented as a separate clock to make use of already
existing common-clock features for disabling the pll if one of the other
two sources is used.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-By: Max Schwarz <max.schwarz@online.de>
Tested-By: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-07-13 12:17:06 -07:00
Heiko Stübner a245fecbb8 clk: rockchip: add basic infrastructure for clock branches
This adds infrastructure for registering clock branches. On Rockchip SoCs
most clock branches are a combination of mux,divider and gate components,
thus a composite clock is used when appropriate.

Clock branches are supposed to be declared in an array using the COMPOSITE*
or MUX, etc makros defined in the header and then registered using
rockchip_clk_register_branches.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-By: Max Schwarz <max.schwarz@online.de>
Tested-By: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-07-13 12:17:06 -07:00