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11#include <linux/clk-provider.h>
12#include <linux/delay.h>
13#include <linux/err.h>
14#include <linux/io.h>
15#include <linux/module.h>
16#include <linux/of_address.h>
17#include <linux/slab.h>
18#include <linux/string.h>
19
20#include "clk-factors.h"
21
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24
25
26
27
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29
30
31
32
33#define to_clk_factors(_hw) container_of(_hw, struct clk_factors, hw)
34
35#define FACTORS_MAX_PARENTS 5
36
37#define SETMASK(len, pos) (((1U << (len)) - 1) << (pos))
38#define CLRMASK(len, pos) (~(SETMASK(len, pos)))
39#define FACTOR_GET(bit, len, reg) (((reg) & SETMASK(len, bit)) >> (bit))
40
41#define FACTOR_SET(bit, len, reg, val) \
42 (((reg) & CLRMASK(len, bit)) | (val << (bit)))
43
44static unsigned long clk_factors_recalc_rate(struct clk_hw *hw,
45 unsigned long parent_rate)
46{
47 u8 n = 1, k = 0, p = 0, m = 0;
48 u32 reg;
49 unsigned long rate;
50 struct clk_factors *factors = to_clk_factors(hw);
51 const struct clk_factors_config *config = factors->config;
52
53
54 reg = readl(factors->reg);
55
56
57 if (config->nwidth != SUNXI_FACTORS_NOT_APPLICABLE)
58 n = FACTOR_GET(config->nshift, config->nwidth, reg);
59 if (config->kwidth != SUNXI_FACTORS_NOT_APPLICABLE)
60 k = FACTOR_GET(config->kshift, config->kwidth, reg);
61 if (config->mwidth != SUNXI_FACTORS_NOT_APPLICABLE)
62 m = FACTOR_GET(config->mshift, config->mwidth, reg);
63 if (config->pwidth != SUNXI_FACTORS_NOT_APPLICABLE)
64 p = FACTOR_GET(config->pshift, config->pwidth, reg);
65
66 if (factors->recalc) {
67 struct factors_request factors_req = {
68 .parent_rate = parent_rate,
69 .n = n,
70 .k = k,
71 .m = m,
72 .p = p,
73 };
74
75
76 if (factors->mux)
77 factors_req.parent_index =
78 (reg >> factors->mux->shift) &
79 factors->mux->mask;
80
81 factors->recalc(&factors_req);
82
83 return factors_req.rate;
84 }
85
86
87 rate = (parent_rate * (n + config->n_start) * (k + 1) >> p) / (m + 1);
88
89 return rate;
90}
91
92static int clk_factors_determine_rate(struct clk_hw *hw,
93 struct clk_rate_request *req)
94{
95 struct clk_factors *factors = to_clk_factors(hw);
96 struct clk_hw *parent, *best_parent = NULL;
97 int i, num_parents;
98 unsigned long parent_rate, best = 0, child_rate, best_child_rate = 0;
99
100
101 num_parents = clk_hw_get_num_parents(hw);
102 for (i = 0; i < num_parents; i++) {
103 struct factors_request factors_req = {
104 .rate = req->rate,
105 .parent_index = i,
106 };
107 parent = clk_hw_get_parent_by_index(hw, i);
108 if (!parent)
109 continue;
110 if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)
111 parent_rate = clk_hw_round_rate(parent, req->rate);
112 else
113 parent_rate = clk_hw_get_rate(parent);
114
115 factors_req.parent_rate = parent_rate;
116 factors->get_factors(&factors_req);
117 child_rate = factors_req.rate;
118
119 if (child_rate <= req->rate && child_rate > best_child_rate) {
120 best_parent = parent;
121 best = parent_rate;
122 best_child_rate = child_rate;
123 }
124 }
125
126 if (!best_parent)
127 return -EINVAL;
128
129 req->best_parent_hw = best_parent;
130 req->best_parent_rate = best;
131 req->rate = best_child_rate;
132
133 return 0;
134}
135
136static int clk_factors_set_rate(struct clk_hw *hw, unsigned long rate,
137 unsigned long parent_rate)
138{
139 struct factors_request req = {
140 .rate = rate,
141 .parent_rate = parent_rate,
142 };
143 u32 reg;
144 struct clk_factors *factors = to_clk_factors(hw);
145 const struct clk_factors_config *config = factors->config;
146 unsigned long flags = 0;
147
148 factors->get_factors(&req);
149
150 if (factors->lock)
151 spin_lock_irqsave(factors->lock, flags);
152
153
154 reg = readl(factors->reg);
155
156
157 reg = FACTOR_SET(config->nshift, config->nwidth, reg, req.n);
158 reg = FACTOR_SET(config->kshift, config->kwidth, reg, req.k);
159 reg = FACTOR_SET(config->mshift, config->mwidth, reg, req.m);
160 reg = FACTOR_SET(config->pshift, config->pwidth, reg, req.p);
161
162
163 writel(reg, factors->reg);
164
165
166 __delay((rate >> 20) * 500 / 2);
167
168 if (factors->lock)
169 spin_unlock_irqrestore(factors->lock, flags);
170
171 return 0;
172}
173
174static const struct clk_ops clk_factors_ops = {
175 .determine_rate = clk_factors_determine_rate,
176 .recalc_rate = clk_factors_recalc_rate,
177 .set_rate = clk_factors_set_rate,
178};
179
180struct clk *sunxi_factors_register(struct device_node *node,
181 const struct factors_data *data,
182 spinlock_t *lock,
183 void __iomem *reg)
184{
185 struct clk *clk;
186 struct clk_factors *factors;
187 struct clk_gate *gate = NULL;
188 struct clk_mux *mux = NULL;
189 struct clk_hw *gate_hw = NULL;
190 struct clk_hw *mux_hw = NULL;
191 const char *clk_name = node->name;
192 const char *parents[FACTORS_MAX_PARENTS];
193 int ret, i = 0;
194
195
196 i = of_clk_parent_fill(node, parents, FACTORS_MAX_PARENTS);
197
198
199
200
201
202 if (data->name)
203 clk_name = data->name;
204 else
205 of_property_read_string(node, "clock-output-names", &clk_name);
206
207 factors = kzalloc(sizeof(struct clk_factors), GFP_KERNEL);
208 if (!factors)
209 goto err_factors;
210
211
212 factors->reg = reg;
213 factors->config = data->table;
214 factors->get_factors = data->getter;
215 factors->recalc = data->recalc;
216 factors->lock = lock;
217
218
219 if (data->enable) {
220 gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
221 if (!gate)
222 goto err_gate;
223
224 factors->gate = gate;
225
226
227 gate->reg = reg;
228 gate->bit_idx = data->enable;
229 gate->lock = factors->lock;
230 gate_hw = &gate->hw;
231 }
232
233
234 if (data->mux) {
235 mux = kzalloc(sizeof(struct clk_mux), GFP_KERNEL);
236 if (!mux)
237 goto err_mux;
238
239 factors->mux = mux;
240
241
242 mux->reg = reg;
243 mux->shift = data->mux;
244 mux->mask = data->muxmask;
245 mux->lock = factors->lock;
246 mux_hw = &mux->hw;
247 }
248
249 clk = clk_register_composite(NULL, clk_name,
250 parents, i,
251 mux_hw, &clk_mux_ops,
252 &factors->hw, &clk_factors_ops,
253 gate_hw, &clk_gate_ops, 0);
254 if (IS_ERR(clk))
255 goto err_register;
256
257 ret = of_clk_add_provider(node, of_clk_src_simple_get, clk);
258 if (ret)
259 goto err_provider;
260
261 return clk;
262
263err_provider:
264
265 clk_unregister(clk);
266err_register:
267 kfree(mux);
268err_mux:
269 kfree(gate);
270err_gate:
271 kfree(factors);
272err_factors:
273 return NULL;
274}
275
276void sunxi_factors_unregister(struct device_node *node, struct clk *clk)
277{
278 struct clk_hw *hw = __clk_get_hw(clk);
279 struct clk_factors *factors;
280 const char *name;
281
282 if (!hw)
283 return;
284
285 factors = to_clk_factors(hw);
286 name = clk_hw_get_name(hw);
287
288 of_clk_del_provider(node);
289
290 clk_unregister(clk);
291 kfree(factors->mux);
292 kfree(factors->gate);
293 kfree(factors);
294}
295