clk: st: Support for PLLs inside ClockGenA(s)

The patch supports the c65/c32 type PLLs used by ClockGenA(s)

PLL clock : It includes support for all c65/c32 type PLLs
inside ClockGenA(s) : implemented as Fixed Parent / Fixed Rate clock,
with clock rate calculated reading H/w settings done at BOOT.

c65 PLLs have 2 outputs : HS and LS
c32 PLLs have 1-4 outputs : ODFx
Signed-off-by: Pankaj Dev <pankaj.dev@st.com>
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

drivers/clk/st/Makefile

-obj-y += clkgen-mux.o
+obj-y += clkgen-mux.o clkgen-pll.o

drivers/clk/st/clkgen.h

+/************************************************************************
+File  : Clock H/w specific Information
+
+Author: Pankaj Dev <pankaj.dev@st.com>
+
+Copyright (C) 2014 STMicroelectronics
+************************************************************************/
+
+#ifndef __CLKGEN_INFO_H
+#define __CLKGEN_INFO_H
+
+struct clkgen_field {
+	unsigned int offset;
+	unsigned int mask;
+	unsigned int shift;
+};
+
+static inline unsigned long clkgen_read(void __iomem	*base,
+					  struct clkgen_field *field)
+{
+	return (readl(base + field->offset) >> field->shift) & field->mask;
+}
+
+
+static inline void clkgen_write(void __iomem *base, struct clkgen_field *field,
+				  unsigned long val)
+{
+	writel((readl(base + field->offset) &
+	       ~(field->mask << field->shift)) | (val << field->shift),
+	       base + field->offset);
+
+	return;
+}
+
+#define CLKGEN_FIELD(_offset, _mask, _shift) {		\
+				.offset	= _offset,	\
+				.mask	= _mask,	\
+				.shift	= _shift,	\
+				}
+
+#define CLKGEN_READ(pll, field) clkgen_read(pll->regs_base, \
+		&pll->data->field)
+
+#define CLKGEN_WRITE(pll, field, val) clkgen_write(pll->regs_base, \
+		&pll->data->field, val)
+
+#endif /*__CLKGEN_INFO_H*/
+