Most of the i.MX clock generic API is built by selecting MXC_CLK.
Without it, the i.MX93 clock driver will fail to build:
aarch64-linux-gnu-ld: drivers/clk/imx/clk-imx93.o:
in function `imx93_clocks_probe': clk-imx93.c:(.text+0xa8):
undefined reference to `imx_obtain_fixed_clk_hw'
So fix this by selecting MXC_CLK for the CLK_IMX93.
Fixes: 24defbe194 ("clk: imx: add i.MX93 clk")
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20220315082446.3120850-1-abel.vesa@nxp.com
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The core clock and M2MC clocks are shared between some devices (Unicam
controllers and the HVS, and the HDMI controllers, respectively) that
will have various, varying, requirements depending on their current work
load.
Since those loads can require a fairly high clock rate in extreme
conditions (up to ~600MHz), we can end up running those clocks at their
maximum frequency even though we no longer require such a high rate.
Fortunately, those devices don't require an exact rate but a minimum
rate, and all the drivers are using clk_set_min_rate. Thus, we can just
rely on the fact that the clk_request minimum (which is the aggregated
minimum of all the clock users) is what we want at all times.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220225143534.405820-11-maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The M2MC clock provides the state machine clock for both HDMI
controllers.
However, if no HDMI monitor is plugged in at boot, its clock rate will
be left at 0 by the firmware and will make any register access end up in
a CPU stall, even though the clock was enabled.
We had some code in the HDMI controller to deal with this before, but it
makes more sense to have it in the clock driver. Move it there.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220225143534.405820-10-maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
We only export a bunch of firmware clocks, and some of them require
special treatment.
This has been do so far using some tests on the clock id in various
places, but this is fairly hard to extend and doesn't scale very well.
Since we'll need some more cases in the next patches, let's switch to a
variant structure that defines the behaviour we need to have for a given
clock.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220225143534.405820-9-maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
When we change a clock minimum or maximum using clk_set_rate_range(),
clk_set_min_rate() or clk_set_max_rate(), the current code will only
trigger a new rate change if the rate is outside of the new boundaries.
However, a clock driver might want to always keep the clock rate to
one of its boundary, for example the minimum to keep the power
consumption as low as possible.
Since they don't always get called though, clock providers don't have the
opportunity to implement this behaviour.
Let's trigger a clk_set_rate() on the previous requested rate every time
clk_set_rate_range() is called. That way, providers that care about the
new boundaries have a chance to adjust the rate, while providers that
don't care about those new boundaries will return the same rate than
before, which will be ignored by clk_set_rate() and won't result in a
new rate change.
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220225143534.405820-7-maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The code in clk_set_rate_range() will, if the current rate is outside of
the new range, force it to the minimum or maximum.
Since it's running under the condition that the rate is either lower
than the minimum, or higher than the maximum, this is equivalent to
using clamp, while being less readable. Let's switch to using clamp
instead.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220225143534.405820-6-maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The current core while setting the min and max rate properly in the
clk_request structure will not make sure that the requested rate is
within these boundaries, leaving it to each and every driver to make
sure it is.
It's not clear if this was on purpose or not, but this introduces some
inconsistencies within the API.
For example, a user setting a range and then calling clk_round_rate()
with a value outside of that range will get the same value back
(ignoring any driver adjustements), effectively ignoring the range that
was just set.
Another one, arguably worse, is that it also makes clk_round_rate() and
clk_set_rate() behave differently if there's a range and the rate being
used for both is outside that range. As we have seen, the rate will be
returned unchanged by clk_round_rate(), but clk_set_rate() will error
out returning -EINVAL.
Let's make sure the framework will always clamp the rate to the current
range found on the clock, which will fix both these inconsistencies.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220225143534.405820-5-maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
If we were to have two users of the same clock, doing something like:
clk_set_rate_range(user1, 1000, 2000);
clk_set_rate_range(user2, 3000, 4000);
The second call would fail with -EINVAL, preventing from getting in a
situation where we end up with impossible limits.
However, this is never explicitly checked against and enforced, and
works by relying on an undocumented behaviour of clk_set_rate().
Indeed, on the first clk_set_rate_range will make sure the current clock
rate is within the new range, so it will be between 1000 and 2000Hz. On
the second clk_set_rate_range(), it will consider (rightfully), that our
current clock is outside of the 3000-4000Hz range, and will call
clk_core_set_rate_nolock() to set it to 3000Hz.
clk_core_set_rate_nolock() will then call clk_calc_new_rates() that will
eventually check that our rate 3000Hz rate is outside the min 3000Hz max
2000Hz range, will bail out, the error will propagate and we'll
eventually return -EINVAL.
This solely relies on the fact that clk_calc_new_rates(), and in
particular clk_core_determine_round_nolock(), won't modify the new rate
allowing the error to be reported. That assumption won't be true for all
drivers, and most importantly we'll break that assumption in a later
patch.
It can also be argued that we shouldn't even reach the point where we're
calling clk_core_set_rate_nolock().
Let's make an explicit check for disjoints range before we're doing
anything.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220225143534.405820-4-maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Any registered clk_core structure can have a NULL pointer in its dev
field. While never actually documented, this is evidenced by the wide
usage of clk_register and clk_hw_register with a NULL device pointer,
and the fact that the core of_clk_hw_register() function also passes a
NULL device pointer.
A call to clk_hw_get_clk() on a clk_hw struct whose clk_core is in that
case will result in a NULL pointer derefence when it calls dev_name() on
that NULL device pointer.
Add a test for this case and use NULL as the dev_id if the device
pointer is NULL.
Fixes: 30d6f8c15d ("clk: add api to get clk consumer from clk_hw")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220225143534.405820-2-maxime@cerno.tech
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
In order that the end of a clk_div_table can be detected, it must be
terminated with a sentinel element (.div = 0).
In owl-s900.s, the { 0, 8 } element was probably meant to be just that,
so this patch changes { 0, 8 } to { 0, 0 }.
Fixes: d47317ca4a ("clk: actions: Add S700 SoC clock support")
Fixes: d85d20053e ("clk: actions: Add S900 SoC clock support")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://lore.kernel.org/r/20220218000922.134857-2-j.neuschaefer@gmx.net
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The JH7100 has additional audio and video clocks at different memory
ranges, but they use the same register layout. Add a header and export
the starfive_jh7100_clk_ops function so the clock implementation can be
reused by drivers handling these clocks.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20220126173953.1016706-6-kernel@esmil.dk
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
It turns out the audio_div clock is a fractional divider where the
lowest byte of the ctrl register is the integer part of the divider and
the 2nd byte is the number of 100th added to the divider.
The children of this clock is used by the audio peripherals for their
sample rate clock, so round to the closest possible rate rather than
always rounding down like regular dividers.
Fixes: 4210be668a ("clk: starfive: Add JH7100 clock generator driver")
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20220126173953.1016706-3-kernel@esmil.dk
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The problem is best illustrated by an example. Suppose a consumer wants
a 4MHz clock rate from a divider with a 10MHz parent. It would then
call
clk_round_rate(clk, 4000000)
which would call into our determine_rate() callback that correctly
rounds up and finds that a divisor of 3 gives the highest possible
frequency below the requested 4MHz and returns 10000000 / 3 = 3333333Hz.
However the consumer would then call
clk_set_rate(clk, 3333333)
but since 3333333 doesn't divide 10000000 evenly our set_rate() callback
would again round the divisor up and set it to 4 which results in an
unnecessarily low rate of 2.5MHz.
Fix it by using DIV_ROUND_CLOSEST in the set_rate() callback.
Fixes: 4210be668a ("clk: starfive: Add JH7100 clock generator driver")
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20220126173953.1016706-2-kernel@esmil.dk
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
There are two identical assignments of pll->base to the same value,
the second assignment is redundant and can be removed.
Cleans up cppcheck warning:
drivers/clk/imx/clk-sscg-pll.c:528:12: style: Variable 'pll->base' is
reassigned a value before the old one has been used. [redundantAssignment]
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220303090508.1125175-1-colin.i.king@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
