spl: dm: Kconfig: split CLK support for SPL and TPL

Introduce TPL_CLK to allow finer-grained selection of TPL features
for feature-rich (i.e. DM-based) TPL stages.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

drivers/clk/Kconfig

@@ -20,6 +20,16 @@ config SPL_CLK
 	  setting up clocks within SPL, and allows the same drivers to be
 	  used as U-Boot proper.
 
+config TPL_CLK
+	bool "Enable clock support in TPL"
+	depends on CLK && TPL_DM
+	help
+	  The clock subsystem adds a small amount of overhead to the image.
+	  If this is acceptable and you have a need to use clock drivers in
+	  SPL, enable this option. It might provide a cleaner interface to
+	  setting up clocks within TPL, and allows the same drivers to be
+	  used as U-Boot proper.
+
 config CLK_BCM6345
 	bool "Clock controller driver for BCM6345"
 	depends on CLK && ARCH_BMIPS

drivers/clk/Makefile

@@ -5,7 +5,7 @@
 # SPDX-License-Identifier:      GPL-2.0+
 #
 
-obj-$(CONFIG_CLK) += clk-uclass.o clk_fixed_rate.o
+obj-$(CONFIG_$(SPL_TPL_)CLK) += clk-uclass.o clk_fixed_rate.o
 obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
 obj-$(CONFIG_SANDBOX) += clk_sandbox.o
 obj-$(CONFIG_SANDBOX) += clk_sandbox_test.o