Merge tag 'pinctrl-v4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
[linux-2.6-block.git] / drivers / clk / at91 / clk-pll.c
CommitLineData
1a748d2b
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1/*
2 * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 */
10
11#include <linux/clk-provider.h>
12#include <linux/clkdev.h>
13#include <linux/clk/at91_pmc.h>
14#include <linux/of.h>
1bdf0232
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15#include <linux/mfd/syscon.h>
16#include <linux/regmap.h>
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17
18#include "pmc.h"
19
20#define PLL_STATUS_MASK(id) (1 << (1 + (id)))
21#define PLL_REG(id) (AT91_CKGR_PLLAR + ((id) * 4))
22#define PLL_DIV_MASK 0xff
23#define PLL_DIV_MAX PLL_DIV_MASK
24#define PLL_DIV(reg) ((reg) & PLL_DIV_MASK)
25#define PLL_MUL(reg, layout) (((reg) >> (layout)->mul_shift) & \
26 (layout)->mul_mask)
3ef9dd2b
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27#define PLL_MUL_MIN 2
28#define PLL_MUL_MASK(layout) ((layout)->mul_mask)
29#define PLL_MUL_MAX(layout) (PLL_MUL_MASK(layout) + 1)
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30#define PLL_ICPR_SHIFT(id) ((id) * 16)
31#define PLL_ICPR_MASK(id) (0xffff << PLL_ICPR_SHIFT(id))
078a3eb5 32#define PLL_MAX_COUNT 0x3f
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33#define PLL_COUNT_SHIFT 8
34#define PLL_OUT_SHIFT 14
35#define PLL_MAX_ID 1
36
37struct clk_pll_characteristics {
38 struct clk_range input;
39 int num_output;
40 struct clk_range *output;
41 u16 *icpll;
42 u8 *out;
43};
44
45struct clk_pll_layout {
46 u32 pllr_mask;
47 u16 mul_mask;
48 u8 mul_shift;
49};
50
51#define to_clk_pll(hw) container_of(hw, struct clk_pll, hw)
52
53struct clk_pll {
54 struct clk_hw hw;
1bdf0232 55 struct regmap *regmap;
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56 u8 id;
57 u8 div;
58 u8 range;
59 u16 mul;
60 const struct clk_pll_layout *layout;
61 const struct clk_pll_characteristics *characteristics;
62};
63
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64static inline bool clk_pll_ready(struct regmap *regmap, int id)
65{
66 unsigned int status;
67
68 regmap_read(regmap, AT91_PMC_SR, &status);
69
70 return status & PLL_STATUS_MASK(id) ? 1 : 0;
71}
72
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73static int clk_pll_prepare(struct clk_hw *hw)
74{
75 struct clk_pll *pll = to_clk_pll(hw);
1bdf0232 76 struct regmap *regmap = pll->regmap;
1a748d2b 77 const struct clk_pll_layout *layout = pll->layout;
e442d234
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78 const struct clk_pll_characteristics *characteristics =
79 pll->characteristics;
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80 u8 id = pll->id;
81 u32 mask = PLL_STATUS_MASK(id);
82 int offset = PLL_REG(id);
83 u8 out = 0;
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84 unsigned int pllr;
85 unsigned int status;
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86 u8 div;
87 u16 mul;
88
1bdf0232 89 regmap_read(regmap, offset, &pllr);
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90 div = PLL_DIV(pllr);
91 mul = PLL_MUL(pllr, layout);
92
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93 regmap_read(regmap, AT91_PMC_SR, &status);
94 if ((status & mask) &&
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95 (div == pll->div && mul == pll->mul))
96 return 0;
97
98 if (characteristics->out)
99 out = characteristics->out[pll->range];
1a748d2b 100
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101 if (characteristics->icpll)
102 regmap_update_bits(regmap, AT91_PMC_PLLICPR, PLL_ICPR_MASK(id),
103 characteristics->icpll[pll->range] << PLL_ICPR_SHIFT(id));
1a748d2b 104
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105 regmap_update_bits(regmap, offset, layout->pllr_mask,
106 pll->div | (PLL_MAX_COUNT << PLL_COUNT_SHIFT) |
107 (out << PLL_OUT_SHIFT) |
108 ((pll->mul & layout->mul_mask) << layout->mul_shift));
109
99a81706
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110 while (!clk_pll_ready(regmap, pll->id))
111 cpu_relax();
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112
113 return 0;
114}
115
116static int clk_pll_is_prepared(struct clk_hw *hw)
117{
118 struct clk_pll *pll = to_clk_pll(hw);
1a748d2b 119
1bdf0232 120 return clk_pll_ready(pll->regmap, pll->id);
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121}
122
123static void clk_pll_unprepare(struct clk_hw *hw)
124{
125 struct clk_pll *pll = to_clk_pll(hw);
1bdf0232 126 unsigned int mask = pll->layout->pllr_mask;
1a748d2b 127
1bdf0232 128 regmap_update_bits(pll->regmap, PLL_REG(pll->id), mask, ~mask);
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129}
130
131static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
132 unsigned long parent_rate)
133{
134 struct clk_pll *pll = to_clk_pll(hw);
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135 unsigned int pllr;
136 u16 mul;
137 u8 div;
138
139 regmap_read(pll->regmap, PLL_REG(pll->id), &pllr);
140
141 div = PLL_DIV(pllr);
142 mul = PLL_MUL(pllr, pll->layout);
87e2ed33 143
1bdf0232 144 if (!div || !mul)
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145 return 0;
146
1bdf0232 147 return (parent_rate / div) * (mul + 1);
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148}
149
150static long clk_pll_get_best_div_mul(struct clk_pll *pll, unsigned long rate,
151 unsigned long parent_rate,
152 u32 *div, u32 *mul,
153 u32 *index) {
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154 const struct clk_pll_layout *layout = pll->layout;
155 const struct clk_pll_characteristics *characteristics =
156 pll->characteristics;
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157 unsigned long bestremainder = ULONG_MAX;
158 unsigned long maxdiv, mindiv, tmpdiv;
159 long bestrate = -ERANGE;
160 unsigned long bestdiv;
161 unsigned long bestmul;
162 int i = 0;
1a748d2b 163
3ef9dd2b 164 /* Check if parent_rate is a valid input rate */
6c7b03e1 165 if (parent_rate < characteristics->input.min)
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166 return -ERANGE;
167
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168 /*
169 * Calculate minimum divider based on the minimum multiplier, the
170 * parent_rate and the requested rate.
171 * Should always be 2 according to the input and output characteristics
172 * of the PLL blocks.
173 */
174 mindiv = (parent_rate * PLL_MUL_MIN) / rate;
175 if (!mindiv)
176 mindiv = 1;
177
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178 if (parent_rate > characteristics->input.max) {
179 tmpdiv = DIV_ROUND_UP(parent_rate, characteristics->input.max);
180 if (tmpdiv > PLL_DIV_MAX)
181 return -ERANGE;
182
183 if (tmpdiv > mindiv)
184 mindiv = tmpdiv;
185 }
186
3ef9dd2b
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187 /*
188 * Calculate the maximum divider which is limited by PLL register
189 * layout (limited by the MUL or DIV field size).
190 */
191 maxdiv = DIV_ROUND_UP(parent_rate * PLL_MUL_MAX(layout), rate);
192 if (maxdiv > PLL_DIV_MAX)
193 maxdiv = PLL_DIV_MAX;
194
195 /*
196 * Iterate over the acceptable divider values to find the best
197 * divider/multiplier pair (the one that generates the closest
198 * rate to the requested one).
199 */
200 for (tmpdiv = mindiv; tmpdiv <= maxdiv; tmpdiv++) {
201 unsigned long remainder;
202 unsigned long tmprate;
203 unsigned long tmpmul;
204
205 /*
206 * Calculate the multiplier associated with the current
207 * divider that provide the closest rate to the requested one.
208 */
209 tmpmul = DIV_ROUND_CLOSEST(rate, parent_rate / tmpdiv);
210 tmprate = (parent_rate / tmpdiv) * tmpmul;
211 if (tmprate > rate)
212 remainder = tmprate - rate;
213 else
214 remainder = rate - tmprate;
215
216 /*
217 * Compare the remainder with the best remainder found until
218 * now and elect a new best multiplier/divider pair if the
219 * current remainder is smaller than the best one.
220 */
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221 if (remainder < bestremainder) {
222 bestremainder = remainder;
1a748d2b 223 bestdiv = tmpdiv;
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224 bestmul = tmpmul;
225 bestrate = tmprate;
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226 }
227
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228 /*
229 * We've found a perfect match!
230 * Stop searching now and use this multiplier/divider pair.
231 */
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232 if (!remainder)
233 break;
234 }
235
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236 /* We haven't found any multiplier/divider pair => return -ERANGE */
237 if (bestrate < 0)
238 return bestrate;
239
240 /* Check if bestrate is a valid output rate */
241 for (i = 0; i < characteristics->num_output; i++) {
242 if (bestrate >= characteristics->output[i].min &&
243 bestrate <= characteristics->output[i].max)
244 break;
245 }
246
247 if (i >= characteristics->num_output)
248 return -ERANGE;
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249
250 if (div)
251 *div = bestdiv;
252 if (mul)
3ef9dd2b 253 *mul = bestmul - 1;
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254 if (index)
255 *index = i;
256
3ef9dd2b 257 return bestrate;
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258}
259
260static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
261 unsigned long *parent_rate)
262{
263 struct clk_pll *pll = to_clk_pll(hw);
264
265 return clk_pll_get_best_div_mul(pll, rate, *parent_rate,
266 NULL, NULL, NULL);
267}
268
269static int clk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
270 unsigned long parent_rate)
271{
272 struct clk_pll *pll = to_clk_pll(hw);
1a748d2b
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273 long ret;
274 u32 div;
275 u32 mul;
276 u32 index;
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277
278 ret = clk_pll_get_best_div_mul(pll, rate, parent_rate,
279 &div, &mul, &index);
280 if (ret < 0)
281 return ret;
282
283 pll->range = index;
284 pll->div = div;
285 pll->mul = mul;
286
287 return 0;
288}
289
290static const struct clk_ops pll_ops = {
291 .prepare = clk_pll_prepare,
292 .unprepare = clk_pll_unprepare,
293 .is_prepared = clk_pll_is_prepared,
294 .recalc_rate = clk_pll_recalc_rate,
295 .round_rate = clk_pll_round_rate,
296 .set_rate = clk_pll_set_rate,
297};
298
f5644f10 299static struct clk_hw * __init
99a81706 300at91_clk_register_pll(struct regmap *regmap, const char *name,
1a748d2b
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301 const char *parent_name, u8 id,
302 const struct clk_pll_layout *layout,
303 const struct clk_pll_characteristics *characteristics)
304{
305 struct clk_pll *pll;
f5644f10 306 struct clk_hw *hw;
1a748d2b 307 struct clk_init_data init;
1a748d2b 308 int offset = PLL_REG(id);
1bdf0232 309 unsigned int pllr;
f5644f10 310 int ret;
1a748d2b
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311
312 if (id > PLL_MAX_ID)
313 return ERR_PTR(-EINVAL);
314
315 pll = kzalloc(sizeof(*pll), GFP_KERNEL);
316 if (!pll)
317 return ERR_PTR(-ENOMEM);
318
319 init.name = name;
320 init.ops = &pll_ops;
321 init.parent_names = &parent_name;
322 init.num_parents = 1;
323 init.flags = CLK_SET_RATE_GATE;
324
325 pll->id = id;
326 pll->hw.init = &init;
327 pll->layout = layout;
328 pll->characteristics = characteristics;
1bdf0232 329 pll->regmap = regmap;
1bdf0232
BB
330 regmap_read(regmap, offset, &pllr);
331 pll->div = PLL_DIV(pllr);
332 pll->mul = PLL_MUL(pllr, layout);
1a748d2b 333
f5644f10
SB
334 hw = &pll->hw;
335 ret = clk_hw_register(NULL, &pll->hw);
336 if (ret) {
1a748d2b 337 kfree(pll);
f5644f10 338 hw = ERR_PTR(ret);
c76a024e 339 }
1a748d2b 340
f5644f10 341 return hw;
1a748d2b
BB
342}
343
344
345static const struct clk_pll_layout at91rm9200_pll_layout = {
346 .pllr_mask = 0x7FFFFFF,
347 .mul_shift = 16,
348 .mul_mask = 0x7FF,
349};
350
351static const struct clk_pll_layout at91sam9g45_pll_layout = {
352 .pllr_mask = 0xFFFFFF,
353 .mul_shift = 16,
354 .mul_mask = 0xFF,
355};
356
357static const struct clk_pll_layout at91sam9g20_pllb_layout = {
358 .pllr_mask = 0x3FFFFF,
359 .mul_shift = 16,
360 .mul_mask = 0x3F,
361};
362
363static const struct clk_pll_layout sama5d3_pll_layout = {
364 .pllr_mask = 0x1FFFFFF,
365 .mul_shift = 18,
366 .mul_mask = 0x7F,
367};
368
369
370static struct clk_pll_characteristics * __init
371of_at91_clk_pll_get_characteristics(struct device_node *np)
372{
373 int i;
374 int offset;
375 u32 tmp;
376 int num_output;
377 u32 num_cells;
378 struct clk_range input;
379 struct clk_range *output;
380 u8 *out = NULL;
381 u16 *icpll = NULL;
382 struct clk_pll_characteristics *characteristics;
383
384 if (of_at91_get_clk_range(np, "atmel,clk-input-range", &input))
385 return NULL;
386
387 if (of_property_read_u32(np, "#atmel,pll-clk-output-range-cells",
388 &num_cells))
389 return NULL;
390
391 if (num_cells < 2 || num_cells > 4)
392 return NULL;
393
394 if (!of_get_property(np, "atmel,pll-clk-output-ranges", &tmp))
395 return NULL;
396 num_output = tmp / (sizeof(u32) * num_cells);
397
398 characteristics = kzalloc(sizeof(*characteristics), GFP_KERNEL);
399 if (!characteristics)
400 return NULL;
401
402 output = kzalloc(sizeof(*output) * num_output, GFP_KERNEL);
403 if (!output)
404 goto out_free_characteristics;
405
406 if (num_cells > 2) {
407 out = kzalloc(sizeof(*out) * num_output, GFP_KERNEL);
408 if (!out)
409 goto out_free_output;
410 }
411
412 if (num_cells > 3) {
413 icpll = kzalloc(sizeof(*icpll) * num_output, GFP_KERNEL);
414 if (!icpll)
415 goto out_free_output;
416 }
417
418 for (i = 0; i < num_output; i++) {
419 offset = i * num_cells;
420 if (of_property_read_u32_index(np,
421 "atmel,pll-clk-output-ranges",
422 offset, &tmp))
423 goto out_free_output;
424 output[i].min = tmp;
425 if (of_property_read_u32_index(np,
426 "atmel,pll-clk-output-ranges",
427 offset + 1, &tmp))
428 goto out_free_output;
429 output[i].max = tmp;
430
431 if (num_cells == 2)
432 continue;
433
434 if (of_property_read_u32_index(np,
435 "atmel,pll-clk-output-ranges",
436 offset + 2, &tmp))
437 goto out_free_output;
438 out[i] = tmp;
439
440 if (num_cells == 3)
441 continue;
442
443 if (of_property_read_u32_index(np,
444 "atmel,pll-clk-output-ranges",
445 offset + 3, &tmp))
446 goto out_free_output;
447 icpll[i] = tmp;
448 }
449
450 characteristics->input = input;
451 characteristics->num_output = num_output;
452 characteristics->output = output;
453 characteristics->out = out;
454 characteristics->icpll = icpll;
455 return characteristics;
456
457out_free_output:
458 kfree(icpll);
459 kfree(out);
460 kfree(output);
461out_free_characteristics:
462 kfree(characteristics);
463 return NULL;
464}
465
466static void __init
1bdf0232 467of_at91_clk_pll_setup(struct device_node *np,
1a748d2b
BB
468 const struct clk_pll_layout *layout)
469{
470 u32 id;
f5644f10 471 struct clk_hw *hw;
1bdf0232 472 struct regmap *regmap;
1a748d2b
BB
473 const char *parent_name;
474 const char *name = np->name;
475 struct clk_pll_characteristics *characteristics;
476
477 if (of_property_read_u32(np, "reg", &id))
478 return;
479
480 parent_name = of_clk_get_parent_name(np, 0);
481
482 of_property_read_string(np, "clock-output-names", &name);
483
1bdf0232
BB
484 regmap = syscon_node_to_regmap(of_get_parent(np));
485 if (IS_ERR(regmap))
486 return;
487
1a748d2b
BB
488 characteristics = of_at91_clk_pll_get_characteristics(np);
489 if (!characteristics)
490 return;
491
f5644f10 492 hw = at91_clk_register_pll(regmap, name, parent_name, id, layout,
1a748d2b 493 characteristics);
f5644f10 494 if (IS_ERR(hw))
1a748d2b
BB
495 goto out_free_characteristics;
496
f5644f10 497 of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw);
1a748d2b
BB
498 return;
499
500out_free_characteristics:
501 kfree(characteristics);
502}
503
1bdf0232 504static void __init of_at91rm9200_clk_pll_setup(struct device_node *np)
1a748d2b 505{
1bdf0232 506 of_at91_clk_pll_setup(np, &at91rm9200_pll_layout);
1a748d2b 507}
1bdf0232
BB
508CLK_OF_DECLARE(at91rm9200_clk_pll, "atmel,at91rm9200-clk-pll",
509 of_at91rm9200_clk_pll_setup);
1a748d2b 510
1bdf0232 511static void __init of_at91sam9g45_clk_pll_setup(struct device_node *np)
1a748d2b 512{
1bdf0232 513 of_at91_clk_pll_setup(np, &at91sam9g45_pll_layout);
1a748d2b 514}
1bdf0232
BB
515CLK_OF_DECLARE(at91sam9g45_clk_pll, "atmel,at91sam9g45-clk-pll",
516 of_at91sam9g45_clk_pll_setup);
1a748d2b 517
1bdf0232 518static void __init of_at91sam9g20_clk_pllb_setup(struct device_node *np)
1a748d2b 519{
1bdf0232 520 of_at91_clk_pll_setup(np, &at91sam9g20_pllb_layout);
1a748d2b 521}
1bdf0232
BB
522CLK_OF_DECLARE(at91sam9g20_clk_pllb, "atmel,at91sam9g20-clk-pllb",
523 of_at91sam9g20_clk_pllb_setup);
1a748d2b 524
1bdf0232 525static void __init of_sama5d3_clk_pll_setup(struct device_node *np)
1a748d2b 526{
1bdf0232 527 of_at91_clk_pll_setup(np, &sama5d3_pll_layout);
1a748d2b 528}
1bdf0232
BB
529CLK_OF_DECLARE(sama5d3_clk_pll, "atmel,sama5d3-clk-pll",
530 of_sama5d3_clk_pll_setup);