clk: renesas: r8a77995: Add missing CPEX clock

The R-Car Gen3 HardWare Manual Errata for Rev. 0.80 (Feb 28, 2018) added
the CPEX clock on R-Car D3. This clock can be selected as a clock
source for CMT1 (Compare Match Timer Type 1).

Add the missing clock to the DT bindings header, and implement support
for it in the clock driver.

Signed-off-by: Geert Uytterhoeven <[e-mail]>
Acked-by: Stephen Boyd <[e-mail]>

drivers/clk/renesas/r8a77995-cpg-mssr.c

···
 
 enum clk_ids {
 	/* Core Clock Outputs exported to DT */
-	LAST_DT_CORE_CLK = R8A77995_CLK_CP,
+	LAST_DT_CORE_CLK = R8A77995_CLK_CPEX,
 
 	/* External Input Clocks */
 	CLK_EXTAL,
···
 
 	DEF_FIXED("cl",        R8A77995_CLK_CL,    CLK_PLL1,      48, 1),
 	DEF_FIXED("cp",        R8A77995_CLK_CP,    CLK_EXTAL,      2, 1),
+	DEF_FIXED("cpex",      R8A77995_CLK_CPEX,  CLK_EXTAL,      4, 1),
 
 	DEF_DIV6_RO("osc",     R8A77995_CLK_OSC,   CLK_EXTAL, CPG_RCKCR,  8),
 

include/dt-bindings/clock/r8a77995-cpg-mssr.h

···
 #define R8A77995_CLK_LV0		38
 #define R8A77995_CLK_LV1		39
 #define R8A77995_CLK_CP			40
+#define R8A77995_CLK_CPEX		41
 
 #endif /* __DT_BINDINGS_CLOCK_R8A77995_CPG_MSSR_H__ */