2 * Copyright (C) 2016 Maxime Ripard
3 * Maxime Ripard <maxime.ripard@free-electrons.com>
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of
8 * the License, or (at your option) any later version.
11 #include <linux/clk-provider.h>
16 static void ccu_mp_find_best(unsigned long parent, unsigned long rate,
17 unsigned int max_m, unsigned int max_p,
18 unsigned int *m, unsigned int *p)
20 unsigned long best_rate = 0;
21 unsigned int best_m = 0, best_p = 0;
24 for (_p = 1; _p <= max_p; _p <<= 1) {
25 for (_m = 1; _m <= max_m; _m++) {
26 unsigned long tmp_rate = parent / _p / _m;
31 if ((rate - tmp_rate) < (rate - best_rate)) {
43 static unsigned long ccu_mp_round_rate(struct ccu_mux_internal *mux,
44 unsigned long parent_rate,
48 struct ccu_mp *cmp = data;
49 unsigned int max_m, max_p;
52 max_m = cmp->m.max ?: 1 << cmp->m.width;
53 max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);
55 ccu_mp_find_best(parent_rate, rate, max_m, max_p, &m, &p);
57 return parent_rate / p / m;
60 static void ccu_mp_disable(struct clk_hw *hw)
62 struct ccu_mp *cmp = hw_to_ccu_mp(hw);
64 return ccu_gate_helper_disable(&cmp->common, cmp->enable);
67 static int ccu_mp_enable(struct clk_hw *hw)
69 struct ccu_mp *cmp = hw_to_ccu_mp(hw);
71 return ccu_gate_helper_enable(&cmp->common, cmp->enable);
74 static int ccu_mp_is_enabled(struct clk_hw *hw)
76 struct ccu_mp *cmp = hw_to_ccu_mp(hw);
78 return ccu_gate_helper_is_enabled(&cmp->common, cmp->enable);
81 static unsigned long ccu_mp_recalc_rate(struct clk_hw *hw,
82 unsigned long parent_rate)
84 struct ccu_mp *cmp = hw_to_ccu_mp(hw);
88 reg = readl(cmp->common.base + cmp->common.reg);
90 m = reg >> cmp->m.shift;
91 m &= (1 << cmp->m.width) - 1;
96 p = reg >> cmp->p.shift;
97 p &= (1 << cmp->p.width) - 1;
99 return (parent_rate >> p) / m;
102 static int ccu_mp_determine_rate(struct clk_hw *hw,
103 struct clk_rate_request *req)
105 struct ccu_mp *cmp = hw_to_ccu_mp(hw);
107 return ccu_mux_helper_determine_rate(&cmp->common, &cmp->mux,
108 req, ccu_mp_round_rate, cmp);
111 static int ccu_mp_set_rate(struct clk_hw *hw, unsigned long rate,
112 unsigned long parent_rate)
114 struct ccu_mp *cmp = hw_to_ccu_mp(hw);
116 unsigned int max_m, max_p;
120 max_m = cmp->m.max ?: 1 << cmp->m.width;
121 max_p = cmp->p.max ?: 1 << ((1 << cmp->p.width) - 1);
123 ccu_mp_find_best(parent_rate, rate, max_m, max_p, &m, &p);
125 spin_lock_irqsave(cmp->common.lock, flags);
127 reg = readl(cmp->common.base + cmp->common.reg);
128 reg &= ~GENMASK(cmp->m.width + cmp->m.shift - 1, cmp->m.shift);
129 reg &= ~GENMASK(cmp->p.width + cmp->p.shift - 1, cmp->p.shift);
130 reg |= (m - cmp->m.offset) << cmp->m.shift;
131 reg |= ilog2(p) << cmp->p.shift;
133 writel(reg, cmp->common.base + cmp->common.reg);
135 spin_unlock_irqrestore(cmp->common.lock, flags);
140 static u8 ccu_mp_get_parent(struct clk_hw *hw)
142 struct ccu_mp *cmp = hw_to_ccu_mp(hw);
144 return ccu_mux_helper_get_parent(&cmp->common, &cmp->mux);
147 static int ccu_mp_set_parent(struct clk_hw *hw, u8 index)
149 struct ccu_mp *cmp = hw_to_ccu_mp(hw);
151 return ccu_mux_helper_set_parent(&cmp->common, &cmp->mux, index);
154 const struct clk_ops ccu_mp_ops = {
155 .disable = ccu_mp_disable,
156 .enable = ccu_mp_enable,
157 .is_enabled = ccu_mp_is_enabled,
159 .get_parent = ccu_mp_get_parent,
160 .set_parent = ccu_mp_set_parent,
162 .determine_rate = ccu_mp_determine_rate,
163 .recalc_rate = ccu_mp_recalc_rate,
164 .set_rate = ccu_mp_set_rate,