1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
4 */
5
6 #include <linux/clk-provider.h>
7 #include <linux/clkdev.h>
8 #include <linux/clk/at91_pmc.h>
9 #include <linux/of.h>
10 #include <linux/mfd/syscon.h>
11 #include <linux/regmap.h>
12
13 #include "pmc.h"
14
15 #define SAM9X5_USB_DIV_SHIFT 8
16 #define SAM9X5_USB_MAX_DIV 0xf
17
18 #define RM9200_USB_DIV_SHIFT 28
19 #define RM9200_USB_DIV_TAB_SIZE 4
20
21 #define SAM9X5_USBS_MASK GENMASK(0, 0)
22 #define SAM9X60_USBS_MASK GENMASK(1, 0)
23
24 struct at91sam9x5_clk_usb {
25 struct clk_hw hw;
26 struct regmap *regmap;
27 u32 usbs_mask;
28 u8 num_parents;
29 };
30
31 #define to_at91sam9x5_clk_usb(hw) \
32 container_of(hw, struct at91sam9x5_clk_usb, hw)
33
34 struct at91rm9200_clk_usb {
35 struct clk_hw hw;
36 struct regmap *regmap;
37 u32 divisors[4];
38 };
39
40 #define to_at91rm9200_clk_usb(hw) \
41 container_of(hw, struct at91rm9200_clk_usb, hw)
42
at91sam9x5_clk_usb_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)43 static unsigned long at91sam9x5_clk_usb_recalc_rate(struct clk_hw *hw,
44 unsigned long parent_rate)
45 {
46 struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
47 unsigned int usbr;
48 u8 usbdiv;
49
50 regmap_read(usb->regmap, AT91_PMC_USB, &usbr);
51 usbdiv = (usbr & AT91_PMC_OHCIUSBDIV) >> SAM9X5_USB_DIV_SHIFT;
52
53 return DIV_ROUND_CLOSEST(parent_rate, (usbdiv + 1));
54 }
55
at91sam9x5_clk_usb_determine_rate(struct clk_hw * hw,struct clk_rate_request * req)56 static int at91sam9x5_clk_usb_determine_rate(struct clk_hw *hw,
57 struct clk_rate_request *req)
58 {
59 struct clk_hw *parent;
60 long best_rate = -EINVAL;
61 unsigned long tmp_rate;
62 int best_diff = -1;
63 int tmp_diff;
64 int i;
65
66 for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
67 int div;
68
69 parent = clk_hw_get_parent_by_index(hw, i);
70 if (!parent)
71 continue;
72
73 for (div = 1; div < SAM9X5_USB_MAX_DIV + 2; div++) {
74 unsigned long tmp_parent_rate;
75
76 tmp_parent_rate = req->rate * div;
77 tmp_parent_rate = clk_hw_round_rate(parent,
78 tmp_parent_rate);
79 if (!tmp_parent_rate)
80 continue;
81
82 tmp_rate = DIV_ROUND_CLOSEST(tmp_parent_rate, div);
83 if (tmp_rate < req->rate)
84 tmp_diff = req->rate - tmp_rate;
85 else
86 tmp_diff = tmp_rate - req->rate;
87
88 if (best_diff < 0 || best_diff > tmp_diff) {
89 best_rate = tmp_rate;
90 best_diff = tmp_diff;
91 req->best_parent_rate = tmp_parent_rate;
92 req->best_parent_hw = parent;
93 }
94
95 if (!best_diff || tmp_rate < req->rate)
96 break;
97 }
98
99 if (!best_diff)
100 break;
101 }
102
103 if (best_rate < 0)
104 return best_rate;
105
106 req->rate = best_rate;
107 return 0;
108 }
109
at91sam9x5_clk_usb_set_parent(struct clk_hw * hw,u8 index)110 static int at91sam9x5_clk_usb_set_parent(struct clk_hw *hw, u8 index)
111 {
112 struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
113
114 if (index >= usb->num_parents)
115 return -EINVAL;
116
117 regmap_update_bits(usb->regmap, AT91_PMC_USB, usb->usbs_mask, index);
118
119 return 0;
120 }
121
at91sam9x5_clk_usb_get_parent(struct clk_hw * hw)122 static u8 at91sam9x5_clk_usb_get_parent(struct clk_hw *hw)
123 {
124 struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
125 unsigned int usbr;
126
127 regmap_read(usb->regmap, AT91_PMC_USB, &usbr);
128
129 return usbr & usb->usbs_mask;
130 }
131
at91sam9x5_clk_usb_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)132 static int at91sam9x5_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
133 unsigned long parent_rate)
134 {
135 struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
136 unsigned long div;
137
138 if (!rate)
139 return -EINVAL;
140
141 div = DIV_ROUND_CLOSEST(parent_rate, rate);
142 if (div > SAM9X5_USB_MAX_DIV + 1 || !div)
143 return -EINVAL;
144
145 regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_OHCIUSBDIV,
146 (div - 1) << SAM9X5_USB_DIV_SHIFT);
147
148 return 0;
149 }
150
151 static const struct clk_ops at91sam9x5_usb_ops = {
152 .recalc_rate = at91sam9x5_clk_usb_recalc_rate,
153 .determine_rate = at91sam9x5_clk_usb_determine_rate,
154 .get_parent = at91sam9x5_clk_usb_get_parent,
155 .set_parent = at91sam9x5_clk_usb_set_parent,
156 .set_rate = at91sam9x5_clk_usb_set_rate,
157 };
158
at91sam9n12_clk_usb_enable(struct clk_hw * hw)159 static int at91sam9n12_clk_usb_enable(struct clk_hw *hw)
160 {
161 struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
162
163 regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_USBS,
164 AT91_PMC_USBS);
165
166 return 0;
167 }
168
at91sam9n12_clk_usb_disable(struct clk_hw * hw)169 static void at91sam9n12_clk_usb_disable(struct clk_hw *hw)
170 {
171 struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
172
173 regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_USBS, 0);
174 }
175
at91sam9n12_clk_usb_is_enabled(struct clk_hw * hw)176 static int at91sam9n12_clk_usb_is_enabled(struct clk_hw *hw)
177 {
178 struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
179 unsigned int usbr;
180
181 regmap_read(usb->regmap, AT91_PMC_USB, &usbr);
182
183 return usbr & AT91_PMC_USBS;
184 }
185
186 static const struct clk_ops at91sam9n12_usb_ops = {
187 .enable = at91sam9n12_clk_usb_enable,
188 .disable = at91sam9n12_clk_usb_disable,
189 .is_enabled = at91sam9n12_clk_usb_is_enabled,
190 .recalc_rate = at91sam9x5_clk_usb_recalc_rate,
191 .determine_rate = at91sam9x5_clk_usb_determine_rate,
192 .set_rate = at91sam9x5_clk_usb_set_rate,
193 };
194
195 static struct clk_hw * __init
_at91sam9x5_clk_register_usb(struct regmap * regmap,const char * name,const char ** parent_names,u8 num_parents,u32 usbs_mask)196 _at91sam9x5_clk_register_usb(struct regmap *regmap, const char *name,
197 const char **parent_names, u8 num_parents,
198 u32 usbs_mask)
199 {
200 struct at91sam9x5_clk_usb *usb;
201 struct clk_hw *hw;
202 struct clk_init_data init;
203 int ret;
204
205 usb = kzalloc(sizeof(*usb), GFP_KERNEL);
206 if (!usb)
207 return ERR_PTR(-ENOMEM);
208
209 init.name = name;
210 init.ops = &at91sam9x5_usb_ops;
211 init.parent_names = parent_names;
212 init.num_parents = num_parents;
213 init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
214 CLK_SET_RATE_PARENT;
215
216 usb->hw.init = &init;
217 usb->regmap = regmap;
218 usb->usbs_mask = usbs_mask;
219 usb->num_parents = num_parents;
220
221 hw = &usb->hw;
222 ret = clk_hw_register(NULL, &usb->hw);
223 if (ret) {
224 kfree(usb);
225 hw = ERR_PTR(ret);
226 }
227
228 return hw;
229 }
230
231 struct clk_hw * __init
at91sam9x5_clk_register_usb(struct regmap * regmap,const char * name,const char ** parent_names,u8 num_parents)232 at91sam9x5_clk_register_usb(struct regmap *regmap, const char *name,
233 const char **parent_names, u8 num_parents)
234 {
235 return _at91sam9x5_clk_register_usb(regmap, name, parent_names,
236 num_parents, SAM9X5_USBS_MASK);
237 }
238
239 struct clk_hw * __init
sam9x60_clk_register_usb(struct regmap * regmap,const char * name,const char ** parent_names,u8 num_parents)240 sam9x60_clk_register_usb(struct regmap *regmap, const char *name,
241 const char **parent_names, u8 num_parents)
242 {
243 return _at91sam9x5_clk_register_usb(regmap, name, parent_names,
244 num_parents, SAM9X60_USBS_MASK);
245 }
246
247 struct clk_hw * __init
at91sam9n12_clk_register_usb(struct regmap * regmap,const char * name,const char * parent_name)248 at91sam9n12_clk_register_usb(struct regmap *regmap, const char *name,
249 const char *parent_name)
250 {
251 struct at91sam9x5_clk_usb *usb;
252 struct clk_hw *hw;
253 struct clk_init_data init;
254 int ret;
255
256 usb = kzalloc(sizeof(*usb), GFP_KERNEL);
257 if (!usb)
258 return ERR_PTR(-ENOMEM);
259
260 init.name = name;
261 init.ops = &at91sam9n12_usb_ops;
262 init.parent_names = &parent_name;
263 init.num_parents = 1;
264 init.flags = CLK_SET_RATE_GATE | CLK_SET_RATE_PARENT;
265
266 usb->hw.init = &init;
267 usb->regmap = regmap;
268
269 hw = &usb->hw;
270 ret = clk_hw_register(NULL, &usb->hw);
271 if (ret) {
272 kfree(usb);
273 hw = ERR_PTR(ret);
274 }
275
276 return hw;
277 }
278
at91rm9200_clk_usb_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)279 static unsigned long at91rm9200_clk_usb_recalc_rate(struct clk_hw *hw,
280 unsigned long parent_rate)
281 {
282 struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
283 unsigned int pllbr;
284 u8 usbdiv;
285
286 regmap_read(usb->regmap, AT91_CKGR_PLLBR, &pllbr);
287
288 usbdiv = (pllbr & AT91_PMC_USBDIV) >> RM9200_USB_DIV_SHIFT;
289 if (usb->divisors[usbdiv])
290 return parent_rate / usb->divisors[usbdiv];
291
292 return 0;
293 }
294
at91rm9200_clk_usb_round_rate(struct clk_hw * hw,unsigned long rate,unsigned long * parent_rate)295 static long at91rm9200_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate,
296 unsigned long *parent_rate)
297 {
298 struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
299 struct clk_hw *parent = clk_hw_get_parent(hw);
300 unsigned long bestrate = 0;
301 int bestdiff = -1;
302 unsigned long tmprate;
303 int tmpdiff;
304 int i = 0;
305
306 for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) {
307 unsigned long tmp_parent_rate;
308
309 if (!usb->divisors[i])
310 continue;
311
312 tmp_parent_rate = rate * usb->divisors[i];
313 tmp_parent_rate = clk_hw_round_rate(parent, tmp_parent_rate);
314 tmprate = DIV_ROUND_CLOSEST(tmp_parent_rate, usb->divisors[i]);
315 if (tmprate < rate)
316 tmpdiff = rate - tmprate;
317 else
318 tmpdiff = tmprate - rate;
319
320 if (bestdiff < 0 || bestdiff > tmpdiff) {
321 bestrate = tmprate;
322 bestdiff = tmpdiff;
323 *parent_rate = tmp_parent_rate;
324 }
325
326 if (!bestdiff)
327 break;
328 }
329
330 return bestrate;
331 }
332
at91rm9200_clk_usb_set_rate(struct clk_hw * hw,unsigned long rate,unsigned long parent_rate)333 static int at91rm9200_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
334 unsigned long parent_rate)
335 {
336 int i;
337 struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
338 unsigned long div;
339
340 if (!rate)
341 return -EINVAL;
342
343 div = DIV_ROUND_CLOSEST(parent_rate, rate);
344
345 for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) {
346 if (usb->divisors[i] == div) {
347 regmap_update_bits(usb->regmap, AT91_CKGR_PLLBR,
348 AT91_PMC_USBDIV,
349 i << RM9200_USB_DIV_SHIFT);
350
351 return 0;
352 }
353 }
354
355 return -EINVAL;
356 }
357
358 static const struct clk_ops at91rm9200_usb_ops = {
359 .recalc_rate = at91rm9200_clk_usb_recalc_rate,
360 .round_rate = at91rm9200_clk_usb_round_rate,
361 .set_rate = at91rm9200_clk_usb_set_rate,
362 };
363
364 struct clk_hw * __init
at91rm9200_clk_register_usb(struct regmap * regmap,const char * name,const char * parent_name,const u32 * divisors)365 at91rm9200_clk_register_usb(struct regmap *regmap, const char *name,
366 const char *parent_name, const u32 *divisors)
367 {
368 struct at91rm9200_clk_usb *usb;
369 struct clk_hw *hw;
370 struct clk_init_data init;
371 int ret;
372
373 usb = kzalloc(sizeof(*usb), GFP_KERNEL);
374 if (!usb)
375 return ERR_PTR(-ENOMEM);
376
377 init.name = name;
378 init.ops = &at91rm9200_usb_ops;
379 init.parent_names = &parent_name;
380 init.num_parents = 1;
381 init.flags = CLK_SET_RATE_PARENT;
382
383 usb->hw.init = &init;
384 usb->regmap = regmap;
385 memcpy(usb->divisors, divisors, sizeof(usb->divisors));
386
387 hw = &usb->hw;
388 ret = clk_hw_register(NULL, &usb->hw);
389 if (ret) {
390 kfree(usb);
391 hw = ERR_PTR(ret);
392 }
393
394 return hw;
395 }
396