ARM i.MX: Add common clock support for pllv1

The pllv1 is found on i.MX1, i.M25, i.MX27, i.MX31 and i.MX35.
Currently only reading the rate is supported.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/mach-imx/clk-pllv1.c

@@ -0,0 +1,66 @@
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <mach/common.h>
+#include <mach/hardware.h>
+#include <mach/clock.h>
+#include "clk.h"
+
+/**
+ * pll v1
+ *
+ * @clk_hw	clock source
+ * @parent	the parent clock name
+ * @base	base address of pll registers
+ *
+ * PLL clock version 1, found on i.MX1/21/25/27/31/35
+ */
+struct clk_pllv1 {
+	struct clk_hw	hw;
+	void __iomem	*base;
+};
+
+#define to_clk_pllv1(clk) (container_of(clk, struct clk_pllv1, clk))
+
+static unsigned long clk_pllv1_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	struct clk_pllv1 *pll = to_clk_pllv1(hw);
+
+	return mxc_decode_pll(readl(pll->base), parent_rate);
+}
+
+struct clk_ops clk_pllv1_ops = {
+	.recalc_rate = clk_pllv1_recalc_rate,
+};
+
+struct clk *imx_clk_pllv1(const char *name, const char *parent,
+		void __iomem *base)
+{
+	struct clk_pllv1 *pll;
+	struct clk *clk;
+	struct clk_init_data init;
+
+	pll = kmalloc(sizeof(*pll), GFP_KERNEL);
+	if (!pll)
+		return ERR_PTR(-ENOMEM);
+
+	pll->base = base;
+
+	init.name = name;
+	init.ops = &clk_pllv1_ops;
+	init.flags = 0;
+	init.parent_names = &parent;
+	init.num_parents = 1;
+
+	pll->hw.init = &init;
+
+	clk = clk_register(NULL, &pll->hw);
+	if (IS_ERR(clk))
+		kfree(pll);
+
+	return clk;
+}