clk: sync of_clk_get_parent_name with upstream ...

Upstream of_clk_get_parent_name only resorts to node name as a fallback.
Instead, it uses the name supplied for registered clocks whenever
possible. On the sama5d2, this results in sckc@f8048050 and slowck,
respectively. So far, sckc@f8048050 in the parents array couldn't be
matched with any existing clock, leading to an inaccurate clock tree.

Port over the v5.8-rc1 state of the function to fix this.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: migrate to SPDX-License-Identifier use ...

Some of these are a product of source sync with Linux, the other were
done with macro assistance by searching for /later/, deleting license text,
adding appropriate SPDX-License-Identifier and manual post-review.

Devices without a license indicated where assumed GPL-2.0-only according
with the project's license.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: print more consistent clock states ...

In clk_dump we only print the state of clk_is_enabled(). Depending on
the clock this can mean different things. When the clock provides an
is_enabled() callback it will print its result, so the enabled state
matches the hardware state of that clock, but doesn't necessarily mean
its parents are enabled. If a clock does not provide an is_enabled()
callback then we rely on our internal enable_count tracker.

Change this to always print the hardware state of the current clock. It
can be:

- disabled: The clock is disabled (as provided by is_enabled())
- enabled: The clock is enabled (as provided by is_enabled())
- always enabled: The clock can't be disabled (no is_enabled callback
                  and can't be enabled/disabled)
- unknown: no is_enabled callback but can be enabled/disabled

Additionally we print the enable_count variable, so from enable_count !=
0 we can know that barebox has enabled the clock.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: Do not let the enable count of critical clocks go below 1 ...

The enable count of critical clocks may not drop below 1. Otherwise
the new parent during a reparenting of a critical clock will not
be enabled.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: initially enable critical clocks ...

Critical clocks have to be enabled initially. We have to do this not
only to enable the clock itself, but also to make sure its parents
stay enabled and also to correctly enable the new parents during
reparenting of the clock.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: Support CLK_IS_CRITICAL flag ...

Support CLK_IS_CRITICAL flag. Simply do not disable the clock even when
the enable count is zero.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: fix NULL deref without OF node in debug message ...

of_clk_add_provider() may be called for devices added via
add_generic_device(). There is no OF node in this case, leading to a crash
when debug logs are enabled.

This affects various i.MX CPUs, which add imx*-ccm clock devices using
add_generic_device().

Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: support pinmux configuration in clock provider nodes ...

Some device trees use pinctrl-* settings inside device tree nodes for
clock providers.

Barebox does not threat clock providers (such as fixed-clock or
gpio-gate-clock) as conventional devices, thus setting default
pinctrl configuration in driver binding code does not happen for
clock providers.

This patch adds setting default pinctrl configuration to of_clk_init(),
just before calling clock provider's probe routine.

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: Make COMMON_CLK_OF_PROVIDER depend on OFTREE ...

Make COMMON_CLK_OF_PROVIDER depend on OFTREE, this way checking for:

	defined(CONFIG_OFTREE) && defined(CONFIG_COMMON_CLK_OF_PROVIDER)

can be simplified to just:

	defined(CONFIG_COMMON_CLK_OF_PROVIDER)

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: Port two helper functions from Linux ...

Port of_clk_get_parent_count() and of_clk_parent_fill() from Linux.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: implement CLK_OPS_PARENT_ENABLE ...

Some clocks may only be modified when their parent clocks are enabled.
The kernel has the CLK_OPS_PARENT_ENABLE flag for this purpose.
Implement it for barebox aswell.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: Keep enable count consistent over reparent ...

When reparenting a clock we have to make sure the new parent is enabled
when the clock was enabled on the old parent. Also we have to decrease
the old parents use counter when the clock was enabled.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: Port of_clk_set_defaults() ...

Port of_clk_set_defautls() from Linux kernel in order to support DT
configurations that require it (e. g. Vybrid).

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/vybrid'

clk: Port clock dependency resolution code ...

Port the clock dependency resolution algorithm utilized by Linux
kernel's version of of_clk_init(), to allow for SoCs whose DT clock
configuration reqires such behaviour for correct initialization (Vybrid
is one such example).

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: add clock command completion ...

This adds tab completion for the clk_* commands.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Merge branch 'for-next/rockchip' ...

Conflicts:
	arch/arm/Kconfig

clk: Treat NULL as dummy clocks ...

NULL pointers should be treated as dummy clocks as done in the kernel.
Using a not fully filled in clk * array for of_clk_add_provider may result
in NULL clks. When these are passed into the clk framework we should not
crash.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

CLK: Check and do not allow to register clock twice ...

Signed-off-by: Andrey Panov <rockford@yandex.ru>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: move of_clk_get_parent_name() to common clk code ...

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

treewide: fix signedness mixups in printf format specifiers ...

This most likely doesn't fix any real bugs, but it's the
right thing to do and reduces the noise level with static
checkers.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: Add parent round/set rate for mux and gate ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: implement clk_round_rate ...

Instead of returning just the current rate implement clk_round_rate
properly.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: add of_clk_init and CLK_OF_DECLARE macro ...

This add barebox versions of of_clk_init for parsing and registering
clock providers from DT. Also, a macro CLK_OF_DECLARE is added, that
allows to put init callbacks into its own section that can be linked
in the binary.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: of: introduce of_clk_src_simple_get ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: add clock lookup from devicetree ...

Taken from the Linuxkernel with some small adjustments for barebox.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: add prototype for clk_is_enabled ...

On MXS we need to poll the busy bit when changing a clock rate, but only
when the parent clocks are enabled. This exposes the already present
function clk_is_enabled which is suitable for this job.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: fix warning: no previous prototype for 'clk_is_enabled' ...

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

clk: Add is_enabled callback ...

This allows us to better detect whether a clk is enabled or not.

- If we can ask a clk, ask it. If it's enabled, go on and ask parents
- If we can't ask it, but it can be enabled, depend on the enable_count.
  if it's positive, go on and ask parents
- If we can't ask it and it cannot be enabled, assume it is enabled
  and ask parents.

This makes the CLK_ALWAYS_ENABLED unnecessary, since the fixed clk now
always returns 1 in its is_enabled callback.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands: clk_dump: denote always enabled clocks ...

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>