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>
17 unsigned long n, min_n, max_n;
18 unsigned long k, min_k, max_k;
19 unsigned long m, min_m, max_m;
20 unsigned long p, min_p, max_p;
23 static void ccu_nkmp_find_best(unsigned long parent, unsigned long rate,
24 struct _ccu_nkmp *nkmp)
26 unsigned long best_rate = 0;
27 unsigned long best_n = 0, best_k = 0, best_m = 0, best_p = 0;
28 unsigned long _n, _k, _m, _p;
30 for (_k = nkmp->min_k; _k <= nkmp->max_k; _k++) {
31 for (_n = nkmp->min_n; _n <= nkmp->max_n; _n++) {
32 for (_m = nkmp->min_m; _m <= nkmp->max_m; _m++) {
33 for (_p = nkmp->min_p; _p <= nkmp->max_p; _p <<= 1) {
34 unsigned long tmp_rate;
36 tmp_rate = parent * _n * _k / (_m * _p);
41 if ((rate - tmp_rate) < (rate - best_rate)) {
59 static void ccu_nkmp_disable(struct clk_hw *hw)
61 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
63 return ccu_gate_helper_disable(&nkmp->common, nkmp->enable);
66 static int ccu_nkmp_enable(struct clk_hw *hw)
68 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
70 return ccu_gate_helper_enable(&nkmp->common, nkmp->enable);
73 static int ccu_nkmp_is_enabled(struct clk_hw *hw)
75 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
77 return ccu_gate_helper_is_enabled(&nkmp->common, nkmp->enable);
80 static unsigned long ccu_nkmp_recalc_rate(struct clk_hw *hw,
81 unsigned long parent_rate)
83 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
84 unsigned long n, m, k, p;
87 reg = readl(nkmp->common.base + nkmp->common.reg);
89 n = reg >> nkmp->n.shift;
90 n &= (1 << nkmp->n.width) - 1;
95 k = reg >> nkmp->k.shift;
96 k &= (1 << nkmp->k.width) - 1;
101 m = reg >> nkmp->m.shift;
102 m &= (1 << nkmp->m.width) - 1;
107 p = reg >> nkmp->p.shift;
108 p &= (1 << nkmp->p.width) - 1;
110 return (parent_rate * n * k >> p) / m;
113 static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate,
114 unsigned long *parent_rate)
116 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
117 struct _ccu_nkmp _nkmp;
119 _nkmp.min_n = nkmp->n.min;
120 _nkmp.max_n = nkmp->n.max ?: 1 << nkmp->n.width;
121 _nkmp.min_k = nkmp->k.min;
122 _nkmp.max_k = nkmp->k.max ?: 1 << nkmp->k.width;
124 _nkmp.max_m = nkmp->m.max ?: 1 << nkmp->m.width;
126 _nkmp.max_p = nkmp->p.max ?: 1 << ((1 << nkmp->p.width) - 1);
128 ccu_nkmp_find_best(*parent_rate, rate, &_nkmp);
130 return *parent_rate * _nkmp.n * _nkmp.k / (_nkmp.m * _nkmp.p);
133 static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate,
134 unsigned long parent_rate)
136 struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw);
137 struct _ccu_nkmp _nkmp;
142 _nkmp.max_n = nkmp->n.max ?: 1 << nkmp->n.width;
144 _nkmp.max_k = nkmp->k.max ?: 1 << nkmp->k.width;
146 _nkmp.max_m = nkmp->m.max ?: 1 << nkmp->m.width;
148 _nkmp.max_p = nkmp->p.max ?: 1 << ((1 << nkmp->p.width) - 1);
150 ccu_nkmp_find_best(parent_rate, rate, &_nkmp);
152 spin_lock_irqsave(nkmp->common.lock, flags);
154 reg = readl(nkmp->common.base + nkmp->common.reg);
155 reg &= ~GENMASK(nkmp->n.width + nkmp->n.shift - 1, nkmp->n.shift);
156 reg &= ~GENMASK(nkmp->k.width + nkmp->k.shift - 1, nkmp->k.shift);
157 reg &= ~GENMASK(nkmp->m.width + nkmp->m.shift - 1, nkmp->m.shift);
158 reg &= ~GENMASK(nkmp->p.width + nkmp->p.shift - 1, nkmp->p.shift);
160 reg |= (_nkmp.n - nkmp->n.offset) << nkmp->n.shift;
161 reg |= (_nkmp.k - nkmp->k.offset) << nkmp->k.shift;
162 reg |= (_nkmp.m - nkmp->m.offset) << nkmp->m.shift;
163 reg |= ilog2(_nkmp.p) << nkmp->p.shift;
165 writel(reg, nkmp->common.base + nkmp->common.reg);
167 spin_unlock_irqrestore(nkmp->common.lock, flags);
169 ccu_helper_wait_for_lock(&nkmp->common, nkmp->lock);
174 const struct clk_ops ccu_nkmp_ops = {
175 .disable = ccu_nkmp_disable,
176 .enable = ccu_nkmp_enable,
177 .is_enabled = ccu_nkmp_is_enabled,
179 .recalc_rate = ccu_nkmp_recalc_rate,
180 .round_rate = ccu_nkmp_round_rate,
181 .set_rate = ccu_nkmp_set_rate,