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11#include <linux/clk-provider.h>
12#include <linux/regmap.h>
13#include <linux/slab.h>
14
15#include "owl-factor.h"
16
17static unsigned int _get_table_maxval(const struct clk_factor_table *table)
18{
19 unsigned int maxval = 0;
20 const struct clk_factor_table *clkt;
21
22 for (clkt = table; clkt->div; clkt++)
23 if (clkt->val > maxval)
24 maxval = clkt->val;
25 return maxval;
26}
27
28static int _get_table_div_mul(const struct clk_factor_table *table,
29 unsigned int val, unsigned int *mul, unsigned int *div)
30{
31 const struct clk_factor_table *clkt;
32
33 for (clkt = table; clkt->div; clkt++) {
34 if (clkt->val == val) {
35 *mul = clkt->mul;
36 *div = clkt->div;
37 return 1;
38 }
39 }
40
41 return 0;
42}
43
44static unsigned int _get_table_val(const struct clk_factor_table *table,
45 unsigned long rate, unsigned long parent_rate)
46{
47 const struct clk_factor_table *clkt;
48 int val = -1;
49 u64 calc_rate;
50
51 for (clkt = table; clkt->div; clkt++) {
52 calc_rate = parent_rate * clkt->mul;
53 do_div(calc_rate, clkt->div);
54
55 if ((unsigned long)calc_rate <= rate) {
56 val = clkt->val;
57 break;
58 }
59 }
60
61 if (val == -1)
62 val = _get_table_maxval(table);
63
64 return val;
65}
66
67static int clk_val_best(struct clk_hw *hw, unsigned long rate,
68 unsigned long *best_parent_rate)
69{
70 struct owl_factor *factor = hw_to_owl_factor(hw);
71 struct owl_factor_hw *factor_hw = &factor->factor_hw;
72 const struct clk_factor_table *clkt = factor_hw->table;
73 unsigned long parent_rate, try_parent_rate, best = 0, cur_rate;
74 unsigned long parent_rate_saved = *best_parent_rate;
75 int bestval = 0;
76
77 if (!rate)
78 rate = 1;
79
80 if (!(clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) {
81 parent_rate = *best_parent_rate;
82 bestval = _get_table_val(clkt, rate, parent_rate);
83 return bestval;
84 }
85
86 for (clkt = factor_hw->table; clkt->div; clkt++) {
87 try_parent_rate = rate * clkt->div / clkt->mul;
88
89 if (try_parent_rate == parent_rate_saved) {
90 pr_debug("%s: [%d %d %d] found try_parent_rate %ld\n",
91 __func__, clkt->val, clkt->mul, clkt->div,
92 try_parent_rate);
93
94
95
96
97
98 *best_parent_rate = parent_rate_saved;
99 return clkt->val;
100 }
101
102 parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw),
103 try_parent_rate);
104 cur_rate = DIV_ROUND_UP(parent_rate, clkt->div) * clkt->mul;
105 if (cur_rate <= rate && cur_rate > best) {
106 bestval = clkt->val;
107 best = cur_rate;
108 *best_parent_rate = parent_rate;
109 }
110 }
111
112 if (!bestval) {
113 bestval = _get_table_maxval(clkt);
114 *best_parent_rate = clk_hw_round_rate(
115 clk_hw_get_parent(hw), 1);
116 }
117
118 return bestval;
119}
120
121long owl_factor_helper_round_rate(struct owl_clk_common *common,
122 const struct owl_factor_hw *factor_hw,
123 unsigned long rate,
124 unsigned long *parent_rate)
125{
126 const struct clk_factor_table *clkt = factor_hw->table;
127 unsigned int val, mul = 0, div = 1;
128
129 val = clk_val_best(&common->hw, rate, parent_rate);
130 _get_table_div_mul(clkt, val, &mul, &div);
131
132 return *parent_rate * mul / div;
133}
134
135static long owl_factor_round_rate(struct clk_hw *hw, unsigned long rate,
136 unsigned long *parent_rate)
137{
138 struct owl_factor *factor = hw_to_owl_factor(hw);
139 struct owl_factor_hw *factor_hw = &factor->factor_hw;
140
141 return owl_factor_helper_round_rate(&factor->common, factor_hw,
142 rate, parent_rate);
143}
144
145unsigned long owl_factor_helper_recalc_rate(struct owl_clk_common *common,
146 const struct owl_factor_hw *factor_hw,
147 unsigned long parent_rate)
148{
149 const struct clk_factor_table *clkt = factor_hw->table;
150 unsigned long long int rate;
151 u32 reg, val, mul, div;
152
153 div = 0;
154 mul = 0;
155
156 regmap_read(common->regmap, factor_hw->reg, ®);
157
158 val = reg >> factor_hw->shift;
159 val &= div_mask(factor_hw);
160
161 _get_table_div_mul(clkt, val, &mul, &div);
162 if (!div) {
163 WARN(!(factor_hw->fct_flags & CLK_DIVIDER_ALLOW_ZERO),
164 "%s: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n",
165 __clk_get_name(common->hw.clk));
166 return parent_rate;
167 }
168
169 rate = (unsigned long long int)parent_rate * mul;
170 do_div(rate, div);
171
172 return rate;
173}
174
175static unsigned long owl_factor_recalc_rate(struct clk_hw *hw,
176 unsigned long parent_rate)
177{
178 struct owl_factor *factor = hw_to_owl_factor(hw);
179 struct owl_factor_hw *factor_hw = &factor->factor_hw;
180 struct owl_clk_common *common = &factor->common;
181
182 return owl_factor_helper_recalc_rate(common, factor_hw, parent_rate);
183}
184
185int owl_factor_helper_set_rate(const struct owl_clk_common *common,
186 const struct owl_factor_hw *factor_hw,
187 unsigned long rate,
188 unsigned long parent_rate)
189{
190 u32 val, reg;
191
192 val = _get_table_val(factor_hw->table, rate, parent_rate);
193
194 if (val > div_mask(factor_hw))
195 val = div_mask(factor_hw);
196
197 regmap_read(common->regmap, factor_hw->reg, ®);
198
199 reg &= ~(div_mask(factor_hw) << factor_hw->shift);
200 reg |= val << factor_hw->shift;
201
202 regmap_write(common->regmap, factor_hw->reg, reg);
203
204 return 0;
205}
206
207static int owl_factor_set_rate(struct clk_hw *hw, unsigned long rate,
208 unsigned long parent_rate)
209{
210 struct owl_factor *factor = hw_to_owl_factor(hw);
211 struct owl_factor_hw *factor_hw = &factor->factor_hw;
212 struct owl_clk_common *common = &factor->common;
213
214 return owl_factor_helper_set_rate(common, factor_hw,
215 rate, parent_rate);
216}
217
218const struct clk_ops owl_factor_ops = {
219 .round_rate = owl_factor_round_rate,
220 .recalc_rate = owl_factor_recalc_rate,
221 .set_rate = owl_factor_set_rate,
222};
223
