ARM: orion5x: switch to use the clock driver for DT platforms

This commit moves the Orion5x platforms using the Device Tree to use
the recently introduced clock driver for Orion5x. To achieve that, it:

 * Adds the necessary DT description of the clock.

 * Selects ORION_CLK to enable the compilation of the clock driver.

 * Call of_clk_init() instead of the Orion5x-specific clock
   initialization function.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1398202002-28530-21-git-send-email-thomas.petazzoni@free-electrons.com
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

arch/arm/boot/dts/orion5x-mv88f5182.dtsi

@@ -15,6 +15,12 @@
 		compatible = "marvell,orion5x-88f5182-mbus", "simple-bus";
 
 		internal-regs {
+			core_clk: core-clocks@10030 {
+				compatible = "marvell,mv88f5182-core-clock";
+				reg = <0x10010 0x4>;
+				#clock-cells = <1>;
+			};
+
 			mbusc: mbus-controller@20000 {
 				compatible = "marvell,mbus-controller";
 				reg = <0x20000 0x100>, <0x1500 0x20>;

arch/arm/mach-orion5x/Kconfig

@@ -5,6 +5,7 @@ menu "Orion Implementations"
 config ARCH_ORION5X_DT
 	bool "Marvell Orion5x Flattened Device Tree"
 	select USE_OF
+	select ORION_CLK
 	help
 	  Say 'Y' here if you want your kernel to support the
 	  Marvell Orion5x using flattened device tree.

arch/arm/mach-orion5x/board-dt.c

@@ -16,6 +16,7 @@
 #include <linux/of_platform.h>
 #include <linux/cpu.h>
 #include <linux/mbus.h>
+#include <linux/clk-provider.h>
 #include <asm/system_misc.h>
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
@@ -43,6 +44,7 @@ static void orion5x_dt_init_early(void)
 static void orion5x_dt_init_time(void)
 {
 	orion5x_timer_init();
+	of_clk_init(NULL);
 }
 
 static void __init orion5x_dt_init(void)
@@ -60,9 +62,6 @@ static void __init orion5x_dt_init(void)
 	 */
 	orion5x_setup_wins();
 
-	/* Setup root of clk tree */
-	clk_init();
-
 	/*
 	 * Don't issue "Wait for Interrupt" instruction if we are
 	 * running on D0 5281 silicon.