clk: rmobile: Add RCar Gen3 clock driver

Add clock driver for the RCar Gen3 R8A7795 and R8A7796 SoCs .
This driver allows reading out the clock configuration set by
previous boot stages and enabling and disabling clock using
the MSTP registers. Setting clock is not supported thus far.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/drivers/clk/renesas/Kconfig b/drivers/clk/renesas/Kconfig
new file mode 100644
index 0000000..07640d1
--- /dev/null
+++ b/drivers/clk/renesas/Kconfig
@@ -0,0 +1,13 @@
+config CLK_RENESAS
+	bool "Renesas clock drivers"
+	depends on CLK && ARCH_RMOBILE
+	help
+	  Enable support for clock present on Renesas RCar SoCs.
+
+config CLK_RCAR_GEN3
+	bool "Renesas RCar Gen3 R8A7795/R8A7796 clock driver"
+	def_bool y if RCAR_GEN3
+	depends on CLK_RENESAS
+	help
+	  Enable this to support the clocks on Renesas RCar Gen3
+	  R8A7795 and R8A7796 SoC.