1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2016 Maxime Ripard
4 * 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_nkm.h"
12
13struct _ccu_nkm {
14 unsigned long n, min_n, max_n;
15 unsigned long k, min_k, max_k;
16 unsigned long m, min_m, max_m;
17};
18
19static unsigned long ccu_nkm_find_best_with_parent_adj(struct ccu_common *common,
20 struct clk_hw *parent_hw,
21 unsigned long *parent, unsigned long rate,
22 struct _ccu_nkm *nkm)
23{
24 unsigned long best_rate = 0, best_parent_rate = *parent;
25 unsigned long best_n = 0, best_k = 0, best_m = 0;
26 unsigned long _n, _k, _m;
27
28 for (_k = nkm->min_k; _k <= nkm->max_k; _k++) {
29 for (_n = nkm->min_n; _n <= nkm->max_n; _n++) {
30 for (_m = nkm->min_m; _m <= nkm->max_m; _m++) {
31 unsigned long tmp_rate, tmp_parent;
32
33 tmp_parent = clk_hw_round_rate(hw: parent_hw, rate: rate * _m / (_n * _k));
34 tmp_rate = tmp_parent * _n * _k / _m;
35
36 if (ccu_is_better_rate(common, target_rate: rate, current_rate: tmp_rate, best_rate) ||
37 (tmp_parent == *parent && tmp_rate == best_rate)) {
38 best_rate = tmp_rate;
39 best_parent_rate = tmp_parent;
40 best_n = _n;
41 best_k = _k;
42 best_m = _m;
43 }
44 }
45 }
46 }
47
48 nkm->n = best_n;
49 nkm->k = best_k;
50 nkm->m = best_m;
51
52 *parent = best_parent_rate;
53
54 return best_rate;
55}
56
57static unsigned long ccu_nkm_find_best(unsigned long parent, unsigned long rate,
58 struct _ccu_nkm *nkm, struct ccu_common *common)
59{
60 unsigned long best_rate = 0;
61 unsigned long best_n = 0, best_k = 0, best_m = 0;
62 unsigned long _n, _k, _m;
63
64 for (_k = nkm->min_k; _k <= nkm->max_k; _k++) {
65 for (_n = nkm->min_n; _n <= nkm->max_n; _n++) {
66 for (_m = nkm->min_m; _m <= nkm->max_m; _m++) {
67 unsigned long tmp_rate;
68
69 tmp_rate = parent * _n * _k / _m;
70
71 if (ccu_is_better_rate(common, target_rate: rate, current_rate: tmp_rate, best_rate)) {
72 best_rate = tmp_rate;
73 best_n = _n;
74 best_k = _k;
75 best_m = _m;
76 }
77 }
78 }
79 }
80
81 nkm->n = best_n;
82 nkm->k = best_k;
83 nkm->m = best_m;
84
85 return best_rate;
86}
87
88static void ccu_nkm_disable(struct clk_hw *hw)
89{
90 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
91
92 return ccu_gate_helper_disable(common: &nkm->common, gate: nkm->enable);
93}
94
95static int ccu_nkm_enable(struct clk_hw *hw)
96{
97 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
98
99 return ccu_gate_helper_enable(common: &nkm->common, gate: nkm->enable);
100}
101
102static int ccu_nkm_is_enabled(struct clk_hw *hw)
103{
104 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
105
106 return ccu_gate_helper_is_enabled(common: &nkm->common, gate: nkm->enable);
107}
108
109static unsigned long ccu_nkm_recalc_rate(struct clk_hw *hw,
110 unsigned long parent_rate)
111{
112 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
113 unsigned long n, m, k, rate;
114 u32 reg;
115
116 reg = readl(addr: nkm->common.base + nkm->common.reg);
117
118 n = reg >> nkm->n.shift;
119 n &= (1 << nkm->n.width) - 1;
120 n += nkm->n.offset;
121 if (!n)
122 n++;
123
124 k = reg >> nkm->k.shift;
125 k &= (1 << nkm->k.width) - 1;
126 k += nkm->k.offset;
127 if (!k)
128 k++;
129
130 m = reg >> nkm->m.shift;
131 m &= (1 << nkm->m.width) - 1;
132 m += nkm->m.offset;
133 if (!m)
134 m++;
135
136 rate = parent_rate * n * k / m;
137
138 if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
139 rate /= nkm->fixed_post_div;
140
141 return rate;
142}
143
144static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux,
145 struct clk_hw *parent_hw,
146 unsigned long *parent_rate,
147 unsigned long rate,
148 void *data)
149{
150 struct ccu_nkm *nkm = data;
151 struct _ccu_nkm _nkm;
152
153 _nkm.min_n = nkm->n.min ?: 1;
154 _nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
155 _nkm.min_k = nkm->k.min ?: 1;
156 _nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
157 _nkm.min_m = 1;
158 _nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
159
160 if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
161 rate *= nkm->fixed_post_div;
162
163 if (!clk_hw_can_set_rate_parent(&nkm->common.hw))
164 rate = ccu_nkm_find_best(parent: *parent_rate, rate, nkm: &_nkm, common: &nkm->common);
165 else
166 rate = ccu_nkm_find_best_with_parent_adj(common: &nkm->common, parent_hw, parent: parent_rate, rate,
167 nkm: &_nkm);
168
169 if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
170 rate /= nkm->fixed_post_div;
171
172 return rate;
173}
174
175static int ccu_nkm_determine_rate(struct clk_hw *hw,
176 struct clk_rate_request *req)
177{
178 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
179
180 return ccu_mux_helper_determine_rate(common: &nkm->common, cm: &nkm->mux,
181 req, round: ccu_nkm_round_rate, data: nkm);
182}
183
184static int ccu_nkm_set_rate(struct clk_hw *hw, unsigned long rate,
185 unsigned long parent_rate)
186{
187 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
188 struct _ccu_nkm _nkm;
189 unsigned long flags;
190 u32 reg;
191
192 if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
193 rate *= nkm->fixed_post_div;
194
195 _nkm.min_n = nkm->n.min ?: 1;
196 _nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
197 _nkm.min_k = nkm->k.min ?: 1;
198 _nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
199 _nkm.min_m = 1;
200 _nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
201
202 ccu_nkm_find_best(parent: parent_rate, rate, nkm: &_nkm, common: &nkm->common);
203
204 spin_lock_irqsave(nkm->common.lock, flags);
205
206 reg = readl(addr: nkm->common.base + nkm->common.reg);
207 reg &= ~GENMASK(nkm->n.width + nkm->n.shift - 1, nkm->n.shift);
208 reg &= ~GENMASK(nkm->k.width + nkm->k.shift - 1, nkm->k.shift);
209 reg &= ~GENMASK(nkm->m.width + nkm->m.shift - 1, nkm->m.shift);
210
211 reg |= (_nkm.n - nkm->n.offset) << nkm->n.shift;
212 reg |= (_nkm.k - nkm->k.offset) << nkm->k.shift;
213 reg |= (_nkm.m - nkm->m.offset) << nkm->m.shift;
214 writel(val: reg, addr: nkm->common.base + nkm->common.reg);
215
216 spin_unlock_irqrestore(lock: nkm->common.lock, flags);
217
218 ccu_helper_wait_for_lock(common: &nkm->common, lock: nkm->lock);
219
220 return 0;
221}
222
223static u8 ccu_nkm_get_parent(struct clk_hw *hw)
224{
225 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
226
227 return ccu_mux_helper_get_parent(common: &nkm->common, cm: &nkm->mux);
228}
229
230static int ccu_nkm_set_parent(struct clk_hw *hw, u8 index)
231{
232 struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
233
234 return ccu_mux_helper_set_parent(common: &nkm->common, cm: &nkm->mux, index);
235}
236
237const struct clk_ops ccu_nkm_ops = {
238 .disable = ccu_nkm_disable,
239 .enable = ccu_nkm_enable,
240 .is_enabled = ccu_nkm_is_enabled,
241
242 .get_parent = ccu_nkm_get_parent,
243 .set_parent = ccu_nkm_set_parent,
244
245 .determine_rate = ccu_nkm_determine_rate,
246 .recalc_rate = ccu_nkm_recalc_rate,
247 .set_rate = ccu_nkm_set_rate,
248};
249EXPORT_SYMBOL_NS_GPL(ccu_nkm_ops, SUNXI_CCU);
250

source code of linux/drivers/clk/sunxi-ng/ccu_nkm.c