xref: /openbmc/u-boot/drivers/clk/clk-uclass.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015 Google, Inc
4  * Written by Simon Glass <sjg@chromium.org>
5  * Copyright (c) 2016, NVIDIA CORPORATION.
6  * Copyright (c) 2018, Theobroma Systems Design und Consulting GmbH
7  */
8 
9 #include <common.h>
10 #include <clk.h>
11 #include <clk-uclass.h>
12 #include <dm.h>
13 #include <dm/read.h>
14 #include <dt-structs.h>
15 #include <errno.h>
16 
17 static inline const struct clk_ops *clk_dev_ops(struct udevice *dev)
18 {
19 	return (const struct clk_ops *)dev->driver->ops;
20 }
21 
22 #if CONFIG_IS_ENABLED(OF_CONTROL)
23 # if CONFIG_IS_ENABLED(OF_PLATDATA)
24 int clk_get_by_index_platdata(struct udevice *dev, int index,
25 			      struct phandle_1_arg *cells, struct clk *clk)
26 {
27 	int ret;
28 
29 	if (index != 0)
30 		return -ENOSYS;
31 	ret = uclass_get_device(UCLASS_CLK, 0, &clk->dev);
32 	if (ret)
33 		return ret;
34 	clk->id = cells[0].arg[0];
35 
36 	return 0;
37 }
38 # else
39 static int clk_of_xlate_default(struct clk *clk,
40 				struct ofnode_phandle_args *args)
41 {
42 	debug("%s(clk=%p)\n", __func__, clk);
43 
44 	if (args->args_count > 1) {
45 		debug("Invaild args_count: %d\n", args->args_count);
46 		return -EINVAL;
47 	}
48 
49 	if (args->args_count)
50 		clk->id = args->args[0];
51 	else
52 		clk->id = 0;
53 
54 	return 0;
55 }
56 
57 static int clk_get_by_indexed_prop(struct udevice *dev, const char *prop_name,
58 				   int index, struct clk *clk)
59 {
60 	int ret;
61 	struct ofnode_phandle_args args;
62 	struct udevice *dev_clk;
63 	const struct clk_ops *ops;
64 
65 	debug("%s(dev=%p, index=%d, clk=%p)\n", __func__, dev, index, clk);
66 
67 	assert(clk);
68 	clk->dev = NULL;
69 
70 	ret = dev_read_phandle_with_args(dev, prop_name, "#clock-cells", 0,
71 					 index, &args);
72 	if (ret) {
73 		debug("%s: fdtdec_parse_phandle_with_args failed: err=%d\n",
74 		      __func__, ret);
75 		return ret;
76 	}
77 
78 	ret = uclass_get_device_by_ofnode(UCLASS_CLK, args.node, &dev_clk);
79 	if (ret) {
80 		debug("%s: uclass_get_device_by_of_offset failed: err=%d\n",
81 		      __func__, ret);
82 		return ret;
83 	}
84 
85 	clk->dev = dev_clk;
86 
87 	ops = clk_dev_ops(dev_clk);
88 
89 	if (ops->of_xlate)
90 		ret = ops->of_xlate(clk, &args);
91 	else
92 		ret = clk_of_xlate_default(clk, &args);
93 	if (ret) {
94 		debug("of_xlate() failed: %d\n", ret);
95 		return ret;
96 	}
97 
98 	return clk_request(dev_clk, clk);
99 }
100 
101 int clk_get_by_index(struct udevice *dev, int index, struct clk *clk)
102 {
103 	return clk_get_by_indexed_prop(dev, "clocks", index, clk);
104 }
105 
106 int clk_get_bulk(struct udevice *dev, struct clk_bulk *bulk)
107 {
108 	int i, ret, err, count;
109 
110 	bulk->count = 0;
111 
112 	count = dev_count_phandle_with_args(dev, "clocks", "#clock-cells");
113 	if (count < 1)
114 		return count;
115 
116 	bulk->clks = devm_kcalloc(dev, count, sizeof(struct clk), GFP_KERNEL);
117 	if (!bulk->clks)
118 		return -ENOMEM;
119 
120 	for (i = 0; i < count; i++) {
121 		ret = clk_get_by_index(dev, i, &bulk->clks[i]);
122 		if (ret < 0)
123 			goto bulk_get_err;
124 
125 		++bulk->count;
126 	}
127 
128 	return 0;
129 
130 bulk_get_err:
131 	err = clk_release_all(bulk->clks, bulk->count);
132 	if (err)
133 		debug("%s: could release all clocks for %p\n",
134 		      __func__, dev);
135 
136 	return ret;
137 }
138 
139 static int clk_set_default_parents(struct udevice *dev)
140 {
141 	struct clk clk, parent_clk;
142 	int index;
143 	int num_parents;
144 	int ret;
145 
146 	num_parents = dev_count_phandle_with_args(dev, "assigned-clock-parents",
147 						  "#clock-cells");
148 	if (num_parents < 0) {
149 		debug("%s: could not read assigned-clock-parents for %p\n",
150 		      __func__, dev);
151 		return 0;
152 	}
153 
154 	for (index = 0; index < num_parents; index++) {
155 		ret = clk_get_by_indexed_prop(dev, "assigned-clock-parents",
156 					      index, &parent_clk);
157 		/* If -ENOENT, this is a no-op entry */
158 		if (ret == -ENOENT)
159 			continue;
160 
161 		if (ret) {
162 			debug("%s: could not get parent clock %d for %s\n",
163 			      __func__, index, dev_read_name(dev));
164 			return ret;
165 		}
166 
167 		ret = clk_get_by_indexed_prop(dev, "assigned-clocks",
168 					      index, &clk);
169 		if (ret) {
170 			debug("%s: could not get assigned clock %d for %s\n",
171 			      __func__, index, dev_read_name(dev));
172 			return ret;
173 		}
174 
175 		ret = clk_set_parent(&clk, &parent_clk);
176 
177 		/*
178 		 * Not all drivers may support clock-reparenting (as of now).
179 		 * Ignore errors due to this.
180 		 */
181 		if (ret == -ENOSYS)
182 			continue;
183 
184 		if (ret) {
185 			debug("%s: failed to reparent clock %d for %s\n",
186 			      __func__, index, dev_read_name(dev));
187 			return ret;
188 		}
189 	}
190 
191 	return 0;
192 }
193 
194 static int clk_set_default_rates(struct udevice *dev)
195 {
196 	struct clk clk;
197 	int index;
198 	int num_rates;
199 	int size;
200 	int ret = 0;
201 	u32 *rates = NULL;
202 
203 	size = dev_read_size(dev, "assigned-clock-rates");
204 	if (size < 0)
205 		return 0;
206 
207 	num_rates = size / sizeof(u32);
208 	rates = calloc(num_rates, sizeof(u32));
209 	if (!rates)
210 		return -ENOMEM;
211 
212 	ret = dev_read_u32_array(dev, "assigned-clock-rates", rates, num_rates);
213 	if (ret)
214 		goto fail;
215 
216 	for (index = 0; index < num_rates; index++) {
217 		/* If 0 is passed, this is a no-op */
218 		if (!rates[index])
219 			continue;
220 
221 		ret = clk_get_by_indexed_prop(dev, "assigned-clocks",
222 					      index, &clk);
223 		if (ret) {
224 			debug("%s: could not get assigned clock %d for %s\n",
225 			      __func__, index, dev_read_name(dev));
226 			continue;
227 		}
228 
229 		ret = clk_set_rate(&clk, rates[index]);
230 		if (ret < 0) {
231 			debug("%s: failed to set rate on clock %d for %s\n",
232 			      __func__, index, dev_read_name(dev));
233 			break;
234 		}
235 	}
236 
237 fail:
238 	free(rates);
239 	return ret;
240 }
241 
242 int clk_set_defaults(struct udevice *dev)
243 {
244 	int ret;
245 
246 	/* If this not in SPL and pre-reloc state, don't take any action. */
247 	if (!(IS_ENABLED(CONFIG_SPL_BUILD) || (gd->flags & GD_FLG_RELOC)))
248 		return 0;
249 
250 	debug("%s(%s)\n", __func__, dev_read_name(dev));
251 
252 	ret = clk_set_default_parents(dev);
253 	if (ret)
254 		return ret;
255 
256 	ret = clk_set_default_rates(dev);
257 	if (ret < 0)
258 		return ret;
259 
260 	return 0;
261 }
262 # endif /* OF_PLATDATA */
263 
264 int clk_get_by_name(struct udevice *dev, const char *name, struct clk *clk)
265 {
266 	int index;
267 
268 	debug("%s(dev=%p, name=%s, clk=%p)\n", __func__, dev, name, clk);
269 	clk->dev = NULL;
270 
271 	index = dev_read_stringlist_search(dev, "clock-names", name);
272 	if (index < 0) {
273 		debug("fdt_stringlist_search() failed: %d\n", index);
274 		return index;
275 	}
276 
277 	return clk_get_by_index(dev, index, clk);
278 }
279 
280 int clk_release_all(struct clk *clk, int count)
281 {
282 	int i, ret;
283 
284 	for (i = 0; i < count; i++) {
285 		debug("%s(clk[%d]=%p)\n", __func__, i, &clk[i]);
286 
287 		/* check if clock has been previously requested */
288 		if (!clk[i].dev)
289 			continue;
290 
291 		ret = clk_disable(&clk[i]);
292 		if (ret && ret != -ENOSYS)
293 			return ret;
294 
295 		ret = clk_free(&clk[i]);
296 		if (ret && ret != -ENOSYS)
297 			return ret;
298 	}
299 
300 	return 0;
301 }
302 
303 #endif /* OF_CONTROL */
304 
305 int clk_request(struct udevice *dev, struct clk *clk)
306 {
307 	const struct clk_ops *ops = clk_dev_ops(dev);
308 
309 	debug("%s(dev=%p, clk=%p)\n", __func__, dev, clk);
310 
311 	clk->dev = dev;
312 
313 	if (!ops->request)
314 		return 0;
315 
316 	return ops->request(clk);
317 }
318 
319 int clk_free(struct clk *clk)
320 {
321 	const struct clk_ops *ops = clk_dev_ops(clk->dev);
322 
323 	debug("%s(clk=%p)\n", __func__, clk);
324 
325 	if (!ops->free)
326 		return 0;
327 
328 	return ops->free(clk);
329 }
330 
331 ulong clk_get_rate(struct clk *clk)
332 {
333 	const struct clk_ops *ops = clk_dev_ops(clk->dev);
334 
335 	debug("%s(clk=%p)\n", __func__, clk);
336 
337 	if (!ops->get_rate)
338 		return -ENOSYS;
339 
340 	return ops->get_rate(clk);
341 }
342 
343 ulong clk_set_rate(struct clk *clk, ulong rate)
344 {
345 	const struct clk_ops *ops = clk_dev_ops(clk->dev);
346 
347 	debug("%s(clk=%p, rate=%lu)\n", __func__, clk, rate);
348 
349 	if (!ops->set_rate)
350 		return -ENOSYS;
351 
352 	return ops->set_rate(clk, rate);
353 }
354 
355 int clk_set_parent(struct clk *clk, struct clk *parent)
356 {
357 	const struct clk_ops *ops = clk_dev_ops(clk->dev);
358 
359 	debug("%s(clk=%p, parent=%p)\n", __func__, clk, parent);
360 
361 	if (!ops->set_parent)
362 		return -ENOSYS;
363 
364 	return ops->set_parent(clk, parent);
365 }
366 
367 int clk_enable(struct clk *clk)
368 {
369 	const struct clk_ops *ops = clk_dev_ops(clk->dev);
370 
371 	debug("%s(clk=%p)\n", __func__, clk);
372 
373 	if (!ops->enable)
374 		return -ENOSYS;
375 
376 	return ops->enable(clk);
377 }
378 
379 int clk_enable_bulk(struct clk_bulk *bulk)
380 {
381 	int i, ret;
382 
383 	for (i = 0; i < bulk->count; i++) {
384 		ret = clk_enable(&bulk->clks[i]);
385 		if (ret < 0 && ret != -ENOSYS)
386 			return ret;
387 	}
388 
389 	return 0;
390 }
391 
392 int clk_disable(struct clk *clk)
393 {
394 	const struct clk_ops *ops = clk_dev_ops(clk->dev);
395 
396 	debug("%s(clk=%p)\n", __func__, clk);
397 
398 	if (!ops->disable)
399 		return -ENOSYS;
400 
401 	return ops->disable(clk);
402 }
403 
404 int clk_disable_bulk(struct clk_bulk *bulk)
405 {
406 	int i, ret;
407 
408 	for (i = 0; i < bulk->count; i++) {
409 		ret = clk_disable(&bulk->clks[i]);
410 		if (ret < 0 && ret != -ENOSYS)
411 			return ret;
412 	}
413 
414 	return 0;
415 }
416 
417 UCLASS_DRIVER(clk) = {
418 	.id		= UCLASS_CLK,
419 	.name		= "clk",
420 };
421