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+/*
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+ * mmp factor clock operation source file
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+ *
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+ * Copyright (C) 2012 Marvell
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+ * Chao Xie <xiechao.mail@gmail.com>
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+ *
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+ * This file is licensed under the terms of the GNU General Public
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+ * License version 2. This program is licensed "as is" without any
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+ * warranty of any kind, whether express or implied.
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+ */
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+
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+#include <linux/clk-provider.h>
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+#include <linux/slab.h>
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+#include <linux/io.h>
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+#include <linux/err.h>
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+
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+#include "clk.h"
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+/*
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+ * It is M/N clock
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+ *
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+ * Fout from synthesizer can be given from two equations:
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+ * numerator/denominator = Fin / (Fout * factor)
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+ */
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+
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+#define to_clk_factor(hw) container_of(hw, struct clk_factor, hw)
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+struct clk_factor {
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+ struct clk_hw hw;
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+ void __iomem *base;
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+ struct clk_factor_masks *masks;
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+ struct clk_factor_tbl *ftbl;
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+ unsigned int ftbl_cnt;
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+};
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+
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+static long clk_factor_round_rate(struct clk_hw *hw, unsigned long drate,
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+ unsigned long *prate)
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+{
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+ struct clk_factor *factor = to_clk_factor(hw);
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+ unsigned long rate = 0, prev_rate;
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+ int i;
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+
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+ for (i = 0; i < factor->ftbl_cnt; i++) {
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+ prev_rate = rate;
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+ rate = (((*prate / 10000) * factor->ftbl[i].num) /
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+ (factor->ftbl[i].den * factor->masks->factor)) * 10000;
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+ if (rate > drate)
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+ break;
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+ }
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+ if (i == 0)
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+ return rate;
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+ else
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+ return prev_rate;
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+}
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+
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+static unsigned long clk_factor_recalc_rate(struct clk_hw *hw,
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+ unsigned long parent_rate)
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+{
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+ struct clk_factor *factor = to_clk_factor(hw);
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+ struct clk_factor_masks *masks = factor->masks;
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+ unsigned int val, num, den;
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+
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+ val = readl_relaxed(factor->base);
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+
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+ /* calculate numerator */
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+ num = (val >> masks->num_shift) & masks->num_mask;
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+
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+ /* calculate denominator */
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+ den = (val >> masks->den_shift) & masks->num_mask;
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+
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+ if (!den)
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+ return 0;
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+
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+ return (((parent_rate / 10000) * den) /
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+ (num * factor->masks->factor)) * 10000;
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+}
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+
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+/* Configures new clock rate*/
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+static int clk_factor_set_rate(struct clk_hw *hw, unsigned long drate,
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+ unsigned long prate)
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+{
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+ struct clk_factor *factor = to_clk_factor(hw);
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+ struct clk_factor_masks *masks = factor->masks;
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+ int i;
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+ unsigned long val;
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+ unsigned long prev_rate, rate = 0;
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+
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+ for (i = 0; i < factor->ftbl_cnt; i++) {
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+ prev_rate = rate;
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+ rate = (((prate / 10000) * factor->ftbl[i].num) /
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+ (factor->ftbl[i].den * factor->masks->factor)) * 10000;
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+ if (rate > drate)
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+ break;
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+ }
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+ if (i > 0)
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+ i--;
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+
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+ val = readl_relaxed(factor->base);
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+
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+ val &= ~(masks->num_mask << masks->num_shift);
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+ val |= (factor->ftbl[i].num & masks->num_mask) << masks->num_shift;
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+
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+ val &= ~(masks->den_mask << masks->den_shift);
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+ val |= (factor->ftbl[i].den & masks->den_mask) << masks->den_shift;
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+
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+ writel_relaxed(val, factor->base);
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+
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+ return 0;
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+}
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+
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+static struct clk_ops clk_factor_ops = {
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+ .recalc_rate = clk_factor_recalc_rate,
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+ .round_rate = clk_factor_round_rate,
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+ .set_rate = clk_factor_set_rate,
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+};
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+
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+struct clk *mmp_clk_register_factor(const char *name, const char *parent_name,
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+ unsigned long flags, void __iomem *base,
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+ struct clk_factor_masks *masks, struct clk_factor_tbl *ftbl,
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+ unsigned int ftbl_cnt)
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+{
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+ struct clk_factor *factor;
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+ struct clk_init_data init;
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+ struct clk *clk;
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+
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+ if (!masks) {
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+ pr_err("%s: must pass a clk_factor_mask\n", __func__);
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+ return ERR_PTR(-EINVAL);
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+ }
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+
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+ factor = kzalloc(sizeof(*factor), GFP_KERNEL);
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+ if (!factor) {
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+ pr_err("%s: could not allocate factor clk\n", __func__);
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+ return ERR_PTR(-ENOMEM);
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+ }
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+
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+ /* struct clk_aux assignments */
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+ factor->base = base;
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+ factor->masks = masks;
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+ factor->ftbl = ftbl;
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+ factor->ftbl_cnt = ftbl_cnt;
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+ factor->hw.init = &init;
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+
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+ init.name = name;
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+ init.ops = &clk_factor_ops;
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+ init.flags = flags;
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+ init.parent_names = &parent_name;
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+ init.num_parents = 1;
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+
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+ clk = clk_register(NULL, &factor->hw);
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+ if (IS_ERR_OR_NULL(clk))
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+ kfree(factor);
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+
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+ return clk;
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+}
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