clk: ingenic: Mark critical clocks in Ingenic SoCs

Consider CPU, L2 cache, and memory clocks as critical to prevent
them -- and the parent clocks -- from being automatically gated,
since nothing calls clk_get() on these clocks.

Gating the CPU clock hangs the processor, and gating memory makes
external DRAM inaccessible. Normal kernel code can't hope to deal
with either situation so those clocks have to be critical.

The L2 cache is required only if caches are running, and could be
gated if the kernel takes care to flush and disable caches before
gating the clock. There's no mechanism to do this, and probably no
reason to do it, so it's simpler to mark the L2 cache as critical.

Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20220428164454.17908-3-aidanmacdonald.0x0@gmail.com
Tested-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com> # On X1000 and X1830
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

dt-bindings: Rename Ingenic CGU headers to ingenic,*.h

Tidy up a bit the tree, by prefixing all include/dt-bindings/clock/ files
related to Ingenic SoCs with 'ingenic,'.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211016133322.40771-1-paul@crapouillou.net

clk: Ingenic: Add RTC related clocks for Ingenic SoCs.

The RTC unit in the Ingenic SoCs has two clock sources, one
is from an external 32.768kHz clock, and the other is from an
external 24MHz/48MHz main clock that is divided by 512. The
choice of these two clocks is controlled by the ERCS bit in
the OPCR register. The RNG unit will also use this clock.

Tested-by: 周正 (Zhou Zheng) <sernia.zhou@foxmail.com>
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Link: https://lore.kernel.org/r/20200725051136.58220-4-zhouyanjie@wanyeetech.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: Ingenic: Add CGU driver for X1830.

Add support for the clocks provided by the CGU in the Ingenic X1830
SoC, making use of the cgu code to do the heavy lifting.

Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lkml.kernel.org/r/20200528031549.13846-6-zhouyanjie@wanyeetech.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>