SPEAr: clk: Add VCO-PLL Synthesizer clock

All SPEAr SoC's contain PLLs. Their Fout is derived based on following equations

- In normal mode
  vco = (2 * M[15:8] * Fin)/N

- In Dithered mode
  vco = (2 * M[15:0] * Fin)/(256 * N)

pll_rate = vco/2^p

vco and pll are very closely bound to each other,
"vco needs to program: mode, m & n" and "pll needs to program p",
both share common enable/disable logic and registers.

This patch adds in support for this type of clock.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Reviewed-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/spear/clk.h b/drivers/clk/spear/clk.h
new file mode 100644
index 0000000..9979b7f
--- /dev/null
+++ b/drivers/clk/spear/clk.h
@@ -0,0 +1,58 @@
+/*
+ * Clock framework definitions for SPEAr platform
+ *
+ * Copyright (C) 2012 ST Microelectronics
+ * Viresh Kumar <viresh.kumar@st.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef __SPEAR_CLK_H
+#define __SPEAR_CLK_H
+
+#include <linux/clk-provider.h>
+#include <linux/spinlock_types.h>
+#include <linux/types.h>
+
+/* VCO-PLL clk */
+struct pll_rate_tbl {
+	u8 mode;
+	u16 m;
+	u8 n;
+	u8 p;
+};
+
+struct clk_vco {
+	struct			clk_hw hw;
+	void __iomem		*mode_reg;
+	void __iomem		*cfg_reg;
+	struct pll_rate_tbl	*rtbl;
+	u8			rtbl_cnt;
+	spinlock_t		*lock;
+};
+
+struct clk_pll {
+	struct			clk_hw hw;
+	struct clk_vco		*vco;
+	const char		*parent[1];
+	spinlock_t		*lock;
+};
+
+typedef unsigned long (*clk_calc_rate)(struct clk_hw *hw, unsigned long prate,
+		int index);
+
+/* clk register routines */
+struct clk *clk_register_vco_pll(const char *vco_name, const char *pll_name,
+		const char *vco_gate_name, const char *parent_name,
+		unsigned long flags, void __iomem *mode_reg, void __iomem
+		*cfg_reg, struct pll_rate_tbl *rtbl, u8 rtbl_cnt,
+		spinlock_t *lock, struct clk **pll_clk,
+		struct clk **vco_gate_clk);
+
+long clk_round_rate_index(struct clk_hw *hw, unsigned long drate,
+		unsigned long parent_rate, clk_calc_rate calc_rate, u8 rtbl_cnt,
+		int *index);
+
+#endif /* __SPEAR_CLK_H */