riscv: clk: Add CLINT clock to kendryte clock driver

Another "virtual" clock (in the sense that it isn't configurable). This
could possibly be done as a clock in the device tree, but I think this is a
bit cleaner.

Signed-off-by: Sean Anderson <seanga2@gmail.com>

drivers/clk/kendryte/clk.c

@@ -646,6 +646,10 @@ static int k210_clk_probe(struct udevice *dev)
 	REGISTER_GATE(K210_CLK_RTC,   "rtc",   in0);
 #undef REGISTER_GATE
 
+	/* The MTIME register in CLINT runs at one 50th the CPU clock speed */
+	clk_dm(K210_CLK_CLINT,
+	       clk_register_fixed_factor(NULL, "clint", "cpu", 0, 1, 50));
+
 	return 0;
 }
 

include/dt-bindings/clock/k210-sysctl.h

@@ -55,5 +55,6 @@
 #define K210_CLK_OTP    43
 #define K210_CLK_RTC    44
 #define K210_CLK_ACLK   45
+#define K210_CLK_CLINT  46
 
 #endif /* CLOCK_K210_SYSCTL_H */