1 files changed, 153 insertions, 0 deletions
diff --git a/drivers/clk/mmp/clk-frac.c b/drivers/clk/mmp/clk-frac.c
new file mode 100644
index 00000000000..80c1dd15d15
--- /dev/null
+++ b/drivers/clk/mmp/clk-frac.c
@@ -0,0 +1,153 @@
+/*
+ * mmp factor clock operation source file
+ *
+ * Copyright (C) 2012 Marvell
+ * Chao Xie <xiechao.mail@gmail.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.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+
+#include "clk.h"
+/*
+ * It is M/N clock
+ *
+ * Fout from synthesizer can be given from two equations:
+ * numerator/denominator = Fin / (Fout * factor)
+ */
+
+#define to_clk_factor(hw) container_of(hw, struct clk_factor, hw)
+struct clk_factor {
+	struct clk_hw		hw;
+	void __iomem		*base;
+	struct clk_factor_masks	*masks;
+	struct clk_factor_tbl	*ftbl;
+	unsigned int		ftbl_cnt;
+};
+
+static long clk_factor_round_rate(struct clk_hw *hw, unsigned long drate,
+		unsigned long *prate)
+{
+	struct clk_factor *factor = to_clk_factor(hw);
+	unsigned long rate = 0, prev_rate;
+	int i;
+
+	for (i = 0; i < factor->ftbl_cnt; i++) {
+		prev_rate = rate;
+		rate = (((*prate / 10000) * factor->ftbl[i].num) /
+			(factor->ftbl[i].den * factor->masks->factor)) * 10000;
+		if (rate > drate)
+			break;
+	}
+	if (i == 0)
+		return rate;
+	else
+		return prev_rate;
+}
+
+static unsigned long clk_factor_recalc_rate(struct clk_hw *hw,
+		unsigned long parent_rate)
+{
+	struct clk_factor *factor = to_clk_factor(hw);
+	struct clk_factor_masks *masks = factor->masks;
+	unsigned int val, num, den;
+
+	val = readl_relaxed(factor->base);
+
+	/* calculate numerator */
+	num = (val >> masks->num_shift) & masks->num_mask;
+
+	/* calculate denominator */
+	den = (val >> masks->den_shift) & masks->num_mask;
+
+	if (!den)
+		return 0;
+
+	return (((parent_rate / 10000)  * den) /
+			(num * factor->masks->factor)) * 10000;
+}
+
+/* Configures new clock rate*/
+static int clk_factor_set_rate(struct clk_hw *hw, unsigned long drate,
+				unsigned long prate)
+{
+	struct clk_factor *factor = to_clk_factor(hw);
+	struct clk_factor_masks *masks = factor->masks;
+	int i;
+	unsigned long val;
+	unsigned long prev_rate, rate = 0;
+
+	for (i = 0; i < factor->ftbl_cnt; i++) {
+		prev_rate = rate;
+		rate = (((prate / 10000) * factor->ftbl[i].num) /
+			(factor->ftbl[i].den * factor->masks->factor)) * 10000;
+		if (rate > drate)
+			break;
+	}
+	if (i > 0)
+		i--;
+
+	val = readl_relaxed(factor->base);
+
+	val &= ~(masks->num_mask << masks->num_shift);
+	val |= (factor->ftbl[i].num & masks->num_mask) << masks->num_shift;
+
+	val &= ~(masks->den_mask << masks->den_shift);
+	val |= (factor->ftbl[i].den & masks->den_mask) << masks->den_shift;
+
+	writel_relaxed(val, factor->base);
+
+	return 0;
+}
+
+static struct clk_ops clk_factor_ops = {
+	.recalc_rate = clk_factor_recalc_rate,
+	.round_rate = clk_factor_round_rate,
+	.set_rate = clk_factor_set_rate,
+};
+
+struct clk *mmp_clk_register_factor(const char *name, const char *parent_name,
+		unsigned long flags, void __iomem *base,
+		struct clk_factor_masks *masks, struct clk_factor_tbl *ftbl,
+		unsigned int ftbl_cnt)
+{
+	struct clk_factor *factor;
+	struct clk_init_data init;
+	struct clk *clk;
+
+	if (!masks) {
+		pr_err("%s: must pass a clk_factor_mask\n", __func__);
+		return ERR_PTR(-EINVAL);
+	}
+
+	factor = kzalloc(sizeof(*factor), GFP_KERNEL);
+	if (!factor) {
+		pr_err("%s: could not allocate factor  clk\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	/* struct clk_aux assignments */
+	factor->base = base;
+	factor->masks = masks;
+	factor->ftbl = ftbl;
+	factor->ftbl_cnt = ftbl_cnt;
+	factor->hw.init = &init;
+
+	init.name = name;
+	init.ops = &clk_factor_ops;
+	init.flags = flags;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	clk = clk_register(NULL, &factor->hw);
+	if (IS_ERR_OR_NULL(clk))
+		kfree(factor);
+
+	return clk;
+}