ARM: 8366/1: move Dual-Timer SP804 driver to drivers/clocksource

The ARM Dual-Timer SP804 module is peripheral found not only on ARM32
platforms but also on ARM64 platforms.

This patch moves the driver out of arch/arm to driver/clocksource
so that it can be used on ARM64 platforms also.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Olof Johansson <olof@lixom.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/clocksource/timer-sp.h

@@ -0,0 +1,30 @@
+/*
+ * ARM timer implementation, found in Integrator, Versatile and Realview
+ * platforms.  Not all platforms support all registers and bits in these
+ * registers, so we mark them with A for Integrator AP, C for Integrator
+ * CP, V for Versatile and R for Realview.
+ *
+ * Integrator AP has 16-bit timers, Integrator CP, Versatile and Realview
+ * can have 16-bit or 32-bit selectable via a bit in the control register.
+ *
+ * Every SP804 contains two identical timers.
+ */
+#define TIMER_1_BASE	0x00
+#define TIMER_2_BASE	0x20
+
+#define TIMER_LOAD	0x00			/* ACVR rw */
+#define TIMER_VALUE	0x04			/* ACVR ro */
+#define TIMER_CTRL	0x08			/* ACVR rw */
+#define TIMER_CTRL_ONESHOT	(1 << 0)	/*  CVR */
+#define TIMER_CTRL_32BIT	(1 << 1)	/*  CVR */
+#define TIMER_CTRL_DIV1		(0 << 2)	/* ACVR */
+#define TIMER_CTRL_DIV16	(1 << 2)	/* ACVR */
+#define TIMER_CTRL_DIV256	(2 << 2)	/* ACVR */
+#define TIMER_CTRL_IE		(1 << 5)	/*   VR */
+#define TIMER_CTRL_PERIODIC	(1 << 6)	/* ACVR */
+#define TIMER_CTRL_ENABLE	(1 << 7)	/* ACVR */
+
+#define TIMER_INTCLR	0x0c			/* ACVR wo */
+#define TIMER_RIS	0x10			/*  CVR ro */
+#define TIMER_MIS	0x14			/*  CVR ro */
+#define TIMER_BGLOAD	0x18			/*  CVR rw */