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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (C) 2016 Maxime Ripard4 * Maxime Ripard <maxime.ripard@free-electrons.com>5 */6 7#include <linux/clk-provider.h>8#include <linux/io.h>9 10#include "ccu_gate.h"11#include "ccu_nk.h"12 13struct _ccu_nk {14 unsigned long n, min_n, max_n;15 unsigned long k, min_k, max_k;16};17 18static unsigned long ccu_nk_find_best(unsigned long parent, unsigned long rate,19 struct _ccu_nk *nk)20{21 unsigned long best_rate = 0;22 unsigned int best_k = 0, best_n = 0;23 unsigned int _k, _n;24 25 for (_k = nk->min_k; _k <= nk->max_k; _k++) {26 for (_n = nk->min_n; _n <= nk->max_n; _n++) {27 unsigned long tmp_rate = parent * _n * _k;28 29 if (tmp_rate > rate)30 continue;31 32 if ((rate - tmp_rate) < (rate - best_rate)) {33 best_rate = tmp_rate;34 best_k = _k;35 best_n = _n;36 }37 }38 }39 40 nk->k = best_k;41 nk->n = best_n;42 43 return best_rate;44}45 46static void ccu_nk_disable(struct clk_hw *hw)47{48 struct ccu_nk *nk = hw_to_ccu_nk(hw);49 50 return ccu_gate_helper_disable(&nk->common, nk->enable);51}52 53static int ccu_nk_enable(struct clk_hw *hw)54{55 struct ccu_nk *nk = hw_to_ccu_nk(hw);56 57 return ccu_gate_helper_enable(&nk->common, nk->enable);58}59 60static int ccu_nk_is_enabled(struct clk_hw *hw)61{62 struct ccu_nk *nk = hw_to_ccu_nk(hw);63 64 return ccu_gate_helper_is_enabled(&nk->common, nk->enable);65}66 67static unsigned long ccu_nk_recalc_rate(struct clk_hw *hw,68 unsigned long parent_rate)69{70 struct ccu_nk *nk = hw_to_ccu_nk(hw);71 unsigned long rate, n, k;72 u32 reg;73 74 reg = readl(nk->common.base + nk->common.reg);75 76 n = reg >> nk->n.shift;77 n &= (1 << nk->n.width) - 1;78 n += nk->n.offset;79 if (!n)80 n++;81 82 k = reg >> nk->k.shift;83 k &= (1 << nk->k.width) - 1;84 k += nk->k.offset;85 if (!k)86 k++;87 88 rate = parent_rate * n * k;89 if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV)90 rate /= nk->fixed_post_div;91 92 return rate;93}94 95static long ccu_nk_round_rate(struct clk_hw *hw, unsigned long rate,96 unsigned long *parent_rate)97{98 struct ccu_nk *nk = hw_to_ccu_nk(hw);99 struct _ccu_nk _nk;100 101 if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV)102 rate *= nk->fixed_post_div;103 104 _nk.min_n = nk->n.min ?: 1;105 _nk.max_n = nk->n.max ?: 1 << nk->n.width;106 _nk.min_k = nk->k.min ?: 1;107 _nk.max_k = nk->k.max ?: 1 << nk->k.width;108 109 rate = ccu_nk_find_best(*parent_rate, rate, &_nk);110 111 if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV)112 rate = rate / nk->fixed_post_div;113 114 return rate;115}116 117static int ccu_nk_set_rate(struct clk_hw *hw, unsigned long rate,118 unsigned long parent_rate)119{120 struct ccu_nk *nk = hw_to_ccu_nk(hw);121 unsigned long flags;122 struct _ccu_nk _nk;123 u32 reg;124 125 if (nk->common.features & CCU_FEATURE_FIXED_POSTDIV)126 rate = rate * nk->fixed_post_div;127 128 _nk.min_n = nk->n.min ?: 1;129 _nk.max_n = nk->n.max ?: 1 << nk->n.width;130 _nk.min_k = nk->k.min ?: 1;131 _nk.max_k = nk->k.max ?: 1 << nk->k.width;132 133 ccu_nk_find_best(parent_rate, rate, &_nk);134 135 spin_lock_irqsave(nk->common.lock, flags);136 137 reg = readl(nk->common.base + nk->common.reg);138 reg &= ~GENMASK(nk->n.width + nk->n.shift - 1, nk->n.shift);139 reg &= ~GENMASK(nk->k.width + nk->k.shift - 1, nk->k.shift);140 141 reg |= (_nk.k - nk->k.offset) << nk->k.shift;142 reg |= (_nk.n - nk->n.offset) << nk->n.shift;143 writel(reg, nk->common.base + nk->common.reg);144 145 spin_unlock_irqrestore(nk->common.lock, flags);146 147 ccu_helper_wait_for_lock(&nk->common, nk->lock);148 149 return 0;150}151 152const struct clk_ops ccu_nk_ops = {153 .disable = ccu_nk_disable,154 .enable = ccu_nk_enable,155 .is_enabled = ccu_nk_is_enabled,156 157 .recalc_rate = ccu_nk_recalc_rate,158 .round_rate = ccu_nk_round_rate,159 .set_rate = ccu_nk_set_rate,160};161EXPORT_SYMBOL_NS_GPL(ccu_nk_ops, SUNXI_CCU);162