summaryrefslogtreecommitdiffstats
path: root/drivers/clk/samsung/clk.c
blob: 0117238391d6532b5b332a0ba09d319b693c03aa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
/*
 * Copyright (c) 2013 Samsung Electronics Co., Ltd.
 * Copyright (c) 2013 Linaro Ltd.
 * Author: Thomas Abraham <thomas.ab@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This file includes utility functions to register clocks to common
 * clock framework for Samsung platforms.
*/

#include <linux/of_address.h>
#include <linux/syscore_ops.h>

#include "clk.h"

static LIST_HEAD(clock_reg_cache_list);

void samsung_clk_save(void __iomem *base,
				    struct samsung_clk_reg_dump *rd,
				    unsigned int num_regs)
{
	for (; num_regs > 0; --num_regs, ++rd)
		rd->value = readl(base + rd->offset);
}

void samsung_clk_restore(void __iomem *base,
				      const struct samsung_clk_reg_dump *rd,
				      unsigned int num_regs)
{
	for (; num_regs > 0; --num_regs, ++rd)
		writel(rd->value, base + rd->offset);
}

struct samsung_clk_reg_dump *samsung_clk_alloc_reg_dump(
						const unsigned long *rdump,
						unsigned long nr_rdump)
{
	struct samsung_clk_reg_dump *rd;
	unsigned int i;

	rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL);
	if (!rd)
		return NULL;

	for (i = 0; i < nr_rdump; ++i)
		rd[i].offset = rdump[i];

	return rd;
}

/* setup the essentials required to support clock lookup using ccf */
struct samsung_clk_provider *__init samsung_clk_init(struct device_node *np,
			void __iomem *base, unsigned long nr_clks)
{
	struct samsung_clk_provider *ctx;
	struct clk **clk_table;
	int i;

	ctx = kzalloc(sizeof(struct samsung_clk_provider), GFP_KERNEL);
	if (!ctx)
		panic("could not allocate clock provider context.\n");

	clk_table = kcalloc(nr_clks, sizeof(struct clk *), GFP_KERNEL);
	if (!clk_table)
		panic("could not allocate clock lookup table\n");

	for (i = 0; i < nr_clks; ++i)
		clk_table[i] = ERR_PTR(-ENOENT);

	ctx->reg_base = base;
	ctx->clk_data.clks = clk_table;
	ctx->clk_data.clk_num = nr_clks;
	spin_lock_init(&ctx->lock);

	return ctx;
}

void __init samsung_clk_of_add_provider(struct device_node *np,
				struct samsung_clk_provider *ctx)
{
	if (np) {
		if (of_clk_add_provider(np, of_clk_src_onecell_get,
					&ctx->clk_data))
			panic("could not register clk provider\n");
	}
}

/* add a clock instance to the clock lookup table used for dt based lookup */
void samsung_clk_add_lookup(struct samsung_clk_provider *ctx, struct clk *clk,
				unsigned int id)
{
	if (ctx->clk_data.clks && id)
		ctx->clk_data.clks[id] = clk;
}

/* register a list of aliases */
void __init samsung_clk_register_alias(struct samsung_clk_provider *ctx,
				const struct samsung_clock_alias *list,
				unsigned int nr_clk)
{
	struct clk *clk;
	unsigned int idx, ret;

	if (!ctx->clk_data.clks) {
		pr_err("%s: clock table missing\n", __func__);
		return;
	}

	for (idx = 0; idx < nr_clk; idx++, list++) {
		if (!list->id) {
			pr_err("%s: clock id missing for index %d\n", __func__,
				idx);
			continue;
		}

		clk = ctx->clk_data.clks[list->id];
		if (!clk) {
			pr_err("%s: failed to find clock %d\n", __func__,
				list->id);
			continue;
		}

		ret = clk_register_clkdev(clk, list->alias, list->dev_name);
		if (ret)
			pr_err("%s: failed to register lookup %s\n",
					__func__, list->alias);
	}
}

/* register a list of fixed clocks */
void __init samsung_clk_register_fixed_rate(struct samsung_clk_provider *ctx,
		const struct samsung_fixed_rate_clock *list,
		unsigned int nr_clk)
{
	struct clk *clk;
	unsigned int idx, ret;

	for (idx = 0; idx < nr_clk; idx++, list++) {
		clk = clk_register_fixed_rate(NULL, list->name,
			list->parent_name, list->flags, list->fixed_rate);
		if (IS_ERR(clk)) {
			pr_err("%s: failed to register clock %s\n", __func__,
				list->name);
			continue;
		}

		samsung_clk_add_lookup(ctx, clk, list->id);

		/*
		 * Unconditionally add a clock lookup for the fixed rate clocks.
		 * There are not many of these on any of Samsung platforms.
		 */
		ret = clk_register_clkdev(clk, list->name, NULL);
		if (ret)
			pr_err("%s: failed to register clock lookup for %s",
				__func__, list->name);
	}
}

/* register a list of fixed factor clocks */
void __init samsung_clk_register_fixed_factor(struct samsung_clk_provider *ctx,
		const struct samsung_fixed_factor_clock *list, unsigned int nr_clk)
{
	struct clk *clk;
	unsigned int idx;

	for (idx = 0; idx < nr_clk; idx++, list++) {
		clk = clk_register_fixed_factor(NULL, list->name,
			list->parent_name, list->flags, list->mult, list->div);
		if (IS_ERR(clk)) {
			pr_err("%s: failed to register clock %s\n", __func__,
				list->name);
			continue;
		}

		samsung_clk_add_lookup(ctx, clk, list->id);
	}
}

/* register a list of mux clocks */
void __init samsung_clk_register_mux(struct samsung_clk_provider *ctx,
				const struct samsung_mux_clock *list,
				unsigned int nr_clk)
{
	struct clk *clk;
	unsigned int idx, ret;

	for (idx = 0; idx < nr_clk; idx++, list++) {
		clk = clk_register_mux(NULL, list->name, list->parent_names,
			list->num_parents, list->flags,
			ctx->reg_base + list->offset,
			list->shift, list->width, list->mux_flags, &ctx->lock);
		if (IS_ERR(clk)) {
			pr_err("%s: failed to register clock %s\n", __func__,
				list->name);
			continue;
		}

		samsung_clk_add_lookup(ctx, clk, list->id);

		/* register a clock lookup only if a clock alias is specified */
		if (list->alias) {
			ret = clk_register_clkdev(clk, list->alias,
						list->dev_name);
			if (ret)
				pr_err("%s: failed to register lookup %s\n",
						__func__, list->alias);
		}
	}
}

/* register a list of div clocks */
void __init samsung_clk_register_div(struct samsung_clk_provider *ctx,
				const struct samsung_div_clock *list,
				unsigned int nr_clk)
{
	struct clk *clk;
	unsigned int idx, ret;

	for (idx = 0; idx < nr_clk; idx++, list++) {
		if (list->table)
			clk = clk_register_divider_table(NULL, list->name,
				list->parent_name, list->flags,
				ctx->reg_base + list->offset,
				list->shift, list->width, list->div_flags,
				list->table, &ctx->lock);
		else
			clk = clk_register_divider(NULL, list->name,
				list->parent_name, list->flags,
				ctx->reg_base + list->offset, list->shift,
				list->width, list->div_flags, &ctx->lock);
		if (IS_ERR(clk)) {
			pr_err("%s: failed to register clock %s\n", __func__,
				list->name);
			continue;
		}

		samsung_clk_add_lookup(ctx, clk, list->id);

		/* register a clock lookup only if a clock alias is specified */
		if (list->alias) {
			ret = clk_register_clkdev(clk, list->alias,
						list->dev_name);
			if (ret)
				pr_err("%s: failed to register lookup %s\n",
						__func__, list->alias);
		}
	}
}

/* register a list of gate clocks */
void __init samsung_clk_register_gate(struct samsung_clk_provider *ctx,
				const struct samsung_gate_clock *list,
				unsigned int nr_clk)
{
	struct clk *clk;
	unsigned int idx, ret;

	for (idx = 0; idx < nr_clk; idx++, list++) {
		clk = clk_register_gate(NULL, list->name, list->parent_name,
				list->flags, ctx->reg_base + list->offset,
				list->bit_idx, list->gate_flags, &ctx->lock);
		if (IS_ERR(clk)) {
			pr_err("%s: failed to register clock %s\n", __func__,
				list->name);
			continue;
		}

		/* register a clock lookup only if a clock alias is specified */
		if (list->alias) {
			ret = clk_register_clkdev(clk, list->alias,
							list->dev_name);
			if (ret)
				pr_err("%s: failed to register lookup %s\n",
					__func__, list->alias);
		}

		samsung_clk_add_lookup(ctx, clk, list->id);
	}
}

/*
 * obtain the clock speed of all external fixed clock sources from device
 * tree and register it
 */
void __init samsung_clk_of_register_fixed_ext(struct samsung_clk_provider *ctx,
			struct samsung_fixed_rate_clock *fixed_rate_clk,
			unsigned int nr_fixed_rate_clk,
			const struct of_device_id *clk_matches)
{
	const struct of_device_id *match;
	struct device_node *clk_np;
	u32 freq;

	for_each_matching_node_and_match(clk_np, clk_matches, &match) {
		if (of_property_read_u32(clk_np, "clock-frequency", &freq))
			continue;
		fixed_rate_clk[(unsigned long)match->data].fixed_rate = freq;
	}
	samsung_clk_register_fixed_rate(ctx, fixed_rate_clk, nr_fixed_rate_clk);
}

/* utility function to get the rate of a specified clock */
unsigned long _get_rate(const char *clk_name)
{
	struct clk *clk;

	clk = __clk_lookup(clk_name);
	if (!clk) {
		pr_err("%s: could not find clock %s\n", __func__, clk_name);
		return 0;
	}

	return clk_get_rate(clk);
}

#ifdef CONFIG_PM_SLEEP
static int samsung_clk_suspend(void)
{
	struct samsung_clock_reg_cache *reg_cache;

	list_for_each_entry(reg_cache, &clock_reg_cache_list, node)
		samsung_clk_save(reg_cache->reg_base, reg_cache->rdump,
				reg_cache->rd_num);
	return 0;
}

static void samsung_clk_resume(void)
{
	struct samsung_clock_reg_cache *reg_cache;

	list_for_each_entry(reg_cache, &clock_reg_cache_list, node)
		samsung_clk_restore(reg_cache->reg_base, reg_cache->rdump,
				reg_cache->rd_num);
}

static struct syscore_ops samsung_clk_syscore_ops = {
	.suspend = samsung_clk_suspend,
	.resume = samsung_clk_resume,
};

static void samsung_clk_sleep_init(void __iomem *reg_base,
		const unsigned long *rdump,
		unsigned long nr_rdump)
{
	struct samsung_clock_reg_cache *reg_cache;

	reg_cache = kzalloc(sizeof(struct samsung_clock_reg_cache),
			GFP_KERNEL);
	if (!reg_cache)
		panic("could not allocate register reg_cache.\n");
	reg_cache->rdump = samsung_clk_alloc_reg_dump(rdump, nr_rdump);

	if (!reg_cache->rdump)
		panic("could not allocate register dump storage.\n");

	if (list_empty(&clock_reg_cache_list))
		register_syscore_ops(&samsung_clk_syscore_ops);

	reg_cache->reg_base = reg_base;
	reg_cache->rd_num = nr_rdump;
	list_add_tail(&reg_cache->node, &clock_reg_cache_list);
}

#else
static void samsung_clk_sleep_init(void __iomem *reg_base,
		const unsigned long *rdump,
		unsigned long nr_rdump) {}
#endif

/*
 * Common function which registers plls, muxes, dividers and gates
 * for each CMU. It also add CMU register list to register cache.
 */
struct samsung_clk_provider * __init samsung_cmu_register_one(
			struct device_node *np,
			struct samsung_cmu_info *cmu)
{
	void __iomem *reg_base;
	struct samsung_clk_provider *ctx;

	reg_base = of_iomap(np, 0);
	if (!reg_base) {
		panic("%s: failed to map registers\n", __func__);
		return NULL;
	}

	ctx = samsung_clk_init(np, reg_base, cmu->nr_clk_ids);
	if (!ctx) {
		panic("%s: unable to allocate ctx\n", __func__);
		return ctx;
	}

	if (cmu->pll_clks)
		samsung_clk_register_pll(ctx, cmu->pll_clks, cmu->nr_pll_clks,
			reg_base);
	if (cmu->mux_clks)
		samsung_clk_register_mux(ctx, cmu->mux_clks,
			cmu->nr_mux_clks);
	if (cmu->div_clks)
		samsung_clk_register_div(ctx, cmu->div_clks, cmu->nr_div_clks);
	if (cmu->gate_clks)
		samsung_clk_register_gate(ctx, cmu->gate_clks,
			cmu->nr_gate_clks);
	if (cmu->fixed_clks)
		samsung_clk_register_fixed_rate(ctx, cmu->fixed_clks,
			cmu->nr_fixed_clks);
	if (cmu->fixed_factor_clks)
		samsung_clk_register_fixed_factor(ctx, cmu->fixed_factor_clks,
			cmu->nr_fixed_factor_clks);
	if (cmu->clk_regs)
		samsung_clk_sleep_init(reg_base, cmu->clk_regs,
			cmu->nr_clk_regs);

	samsung_clk_of_add_provider(np, ctx);

	return ctx;
}