clk: sophgo: Add SG2042 clock driver

Add a driver for the SOPHGO SG2042 clocks.

Signed-off-by: Chen Wang <unicorn_wang@outlook.com>

drivers/clk/sophgo/Kconfig

@@ -9,3 +9,31 @@ config CLK_SOPHGO_CV1800
 	  The driver require a 25MHz Oscillator to function generate clock.
 	  It includes PLLs, common clock function and some vendor clock for
 	  IPs of CV18XX series SoC
+
+config CLK_SOPHGO_SG2042_PLL
+	tristate "Sophgo SG2042 PLL clock support"
+	depends on ARCH_SOPHGO || COMPILE_TEST
+	help
+	  This driver supports the PLL clock controller on the
+	  Sophgo SG2042 SoC. This clock IP uses three oscillators with
+	  frequency of 25 MHz as input, which are used for Main/Fixed
+	  PLL, DDR PLL 0 and DDR PLL 1 respectively.
+
+config CLK_SOPHGO_SG2042_CLKGEN
+	tristate "Sophgo SG2042 Clock Generator support"
+	depends on CLK_SOPHGO_SG2042_PLL
+	help
+	  This driver supports the Clock Generator on the
+	  Sophgo SG2042 SoC. This clock IP depends on SG2042 PLL clock
+	  because it uses PLL clocks as input.
+	  This driver provides clock function such as DIV/Mux/Gate.
+
+config CLK_SOPHGO_SG2042_RPGATE
+	tristate "Sophgo SG2042 RP subsystem clock controller support"
+	depends on CLK_SOPHGO_SG2042_CLKGEN
+	help
+	  This driver supports the RP((Riscv Processors)) subsystem clock
+	  controller on the Sophgo SG2042 SoC.
+	  This clock IP depends on SG2042 Clock Generator because it uses
+	  clock from Clock Generator IP as input.
+	  This driver provides Gate function for RP.

drivers/clk/sophgo/Makefile

@@ -5,3 +5,7 @@ clk-sophgo-cv1800-y		+= clk-cv1800.o
 clk-sophgo-cv1800-y		+= clk-cv18xx-common.o
 clk-sophgo-cv1800-y		+= clk-cv18xx-ip.o
 clk-sophgo-cv1800-y		+= clk-cv18xx-pll.o
+
+obj-$(CONFIG_CLK_SOPHGO_SG2042_CLKGEN)	+= clk-sg2042-clkgen.o
+obj-$(CONFIG_CLK_SOPHGO_SG2042_PLL)	+= clk-sg2042-pll.o
+obj-$(CONFIG_CLK_SOPHGO_SG2042_RPGATE)	+= clk-sg2042-rpgate.o