1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2013 Samsung Electronics Co., Ltd.
4 * Copyright (c) 2013 Linaro Ltd.
5 * Author: Thomas Abraham <thomas.ab@samsung.com>
6 *
7 * This file includes utility functions to register clocks to common
8 * clock framework for Samsung platforms.
9 */
10
11 #include <linux/slab.h>
12 #include <linux/clkdev.h>
13 #include <linux/clk.h>
14 #include <linux/clk-provider.h>
15 #include <linux/io.h>
16 #include <linux/of_address.h>
17 #include <linux/syscore_ops.h>
18
19 #include "clk.h"
20
21 static LIST_HEAD(clock_reg_cache_list);
22
samsung_clk_save(void __iomem * base,struct samsung_clk_reg_dump * rd,unsigned int num_regs)23 void samsung_clk_save(void __iomem *base,
24 struct samsung_clk_reg_dump *rd,
25 unsigned int num_regs)
26 {
27 for (; num_regs > 0; --num_regs, ++rd)
28 rd->value = readl(base + rd->offset);
29 }
30
samsung_clk_restore(void __iomem * base,const struct samsung_clk_reg_dump * rd,unsigned int num_regs)31 void samsung_clk_restore(void __iomem *base,
32 const struct samsung_clk_reg_dump *rd,
33 unsigned int num_regs)
34 {
35 for (; num_regs > 0; --num_regs, ++rd)
36 writel(rd->value, base + rd->offset);
37 }
38
samsung_clk_alloc_reg_dump(const unsigned long * rdump,unsigned long nr_rdump)39 struct samsung_clk_reg_dump *samsung_clk_alloc_reg_dump(
40 const unsigned long *rdump,
41 unsigned long nr_rdump)
42 {
43 struct samsung_clk_reg_dump *rd;
44 unsigned int i;
45
46 rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL);
47 if (!rd)
48 return NULL;
49
50 for (i = 0; i < nr_rdump; ++i)
51 rd[i].offset = rdump[i];
52
53 return rd;
54 }
55
56 /* setup the essentials required to support clock lookup using ccf */
samsung_clk_init(struct device_node * np,void __iomem * base,unsigned long nr_clks)57 struct samsung_clk_provider *__init samsung_clk_init(struct device_node *np,
58 void __iomem *base, unsigned long nr_clks)
59 {
60 struct samsung_clk_provider *ctx;
61 int i;
62
63 ctx = kzalloc(struct_size(ctx, clk_data.hws, nr_clks), GFP_KERNEL);
64 if (!ctx)
65 panic("could not allocate clock provider context.\n");
66
67 for (i = 0; i < nr_clks; ++i)
68 ctx->clk_data.hws[i] = ERR_PTR(-ENOENT);
69
70 ctx->reg_base = base;
71 ctx->clk_data.num = nr_clks;
72 spin_lock_init(&ctx->lock);
73
74 return ctx;
75 }
76
samsung_clk_of_add_provider(struct device_node * np,struct samsung_clk_provider * ctx)77 void __init samsung_clk_of_add_provider(struct device_node *np,
78 struct samsung_clk_provider *ctx)
79 {
80 if (np) {
81 if (of_clk_add_hw_provider(np, of_clk_hw_onecell_get,
82 &ctx->clk_data))
83 panic("could not register clk provider\n");
84 }
85 }
86
87 /* add a clock instance to the clock lookup table used for dt based lookup */
samsung_clk_add_lookup(struct samsung_clk_provider * ctx,struct clk_hw * clk_hw,unsigned int id)88 void samsung_clk_add_lookup(struct samsung_clk_provider *ctx,
89 struct clk_hw *clk_hw, unsigned int id)
90 {
91 if (id)
92 ctx->clk_data.hws[id] = clk_hw;
93 }
94
95 /* register a list of aliases */
samsung_clk_register_alias(struct samsung_clk_provider * ctx,const struct samsung_clock_alias * list,unsigned int nr_clk)96 void __init samsung_clk_register_alias(struct samsung_clk_provider *ctx,
97 const struct samsung_clock_alias *list,
98 unsigned int nr_clk)
99 {
100 struct clk_hw *clk_hw;
101 unsigned int idx, ret;
102
103 for (idx = 0; idx < nr_clk; idx++, list++) {
104 if (!list->id) {
105 pr_err("%s: clock id missing for index %d\n", __func__,
106 idx);
107 continue;
108 }
109
110 clk_hw = ctx->clk_data.hws[list->id];
111 if (!clk_hw) {
112 pr_err("%s: failed to find clock %d\n", __func__,
113 list->id);
114 continue;
115 }
116
117 ret = clk_hw_register_clkdev(clk_hw, list->alias,
118 list->dev_name);
119 if (ret)
120 pr_err("%s: failed to register lookup %s\n",
121 __func__, list->alias);
122 }
123 }
124
125 /* register a list of fixed clocks */
samsung_clk_register_fixed_rate(struct samsung_clk_provider * ctx,const struct samsung_fixed_rate_clock * list,unsigned int nr_clk)126 void __init samsung_clk_register_fixed_rate(struct samsung_clk_provider *ctx,
127 const struct samsung_fixed_rate_clock *list,
128 unsigned int nr_clk)
129 {
130 struct clk_hw *clk_hw;
131 unsigned int idx, ret;
132
133 for (idx = 0; idx < nr_clk; idx++, list++) {
134 clk_hw = clk_hw_register_fixed_rate(ctx->dev, list->name,
135 list->parent_name, list->flags, list->fixed_rate);
136 if (IS_ERR(clk_hw)) {
137 pr_err("%s: failed to register clock %s\n", __func__,
138 list->name);
139 continue;
140 }
141
142 samsung_clk_add_lookup(ctx, clk_hw, list->id);
143
144 /*
145 * Unconditionally add a clock lookup for the fixed rate clocks.
146 * There are not many of these on any of Samsung platforms.
147 */
148 ret = clk_hw_register_clkdev(clk_hw, list->name, NULL);
149 if (ret)
150 pr_err("%s: failed to register clock lookup for %s",
151 __func__, list->name);
152 }
153 }
154
155 /* register a list of fixed factor clocks */
samsung_clk_register_fixed_factor(struct samsung_clk_provider * ctx,const struct samsung_fixed_factor_clock * list,unsigned int nr_clk)156 void __init samsung_clk_register_fixed_factor(struct samsung_clk_provider *ctx,
157 const struct samsung_fixed_factor_clock *list, unsigned int nr_clk)
158 {
159 struct clk_hw *clk_hw;
160 unsigned int idx;
161
162 for (idx = 0; idx < nr_clk; idx++, list++) {
163 clk_hw = clk_hw_register_fixed_factor(ctx->dev, list->name,
164 list->parent_name, list->flags, list->mult, list->div);
165 if (IS_ERR(clk_hw)) {
166 pr_err("%s: failed to register clock %s\n", __func__,
167 list->name);
168 continue;
169 }
170
171 samsung_clk_add_lookup(ctx, clk_hw, list->id);
172 }
173 }
174
175 /* register a list of mux clocks */
samsung_clk_register_mux(struct samsung_clk_provider * ctx,const struct samsung_mux_clock * list,unsigned int nr_clk)176 void __init samsung_clk_register_mux(struct samsung_clk_provider *ctx,
177 const struct samsung_mux_clock *list,
178 unsigned int nr_clk)
179 {
180 struct clk_hw *clk_hw;
181 unsigned int idx;
182
183 for (idx = 0; idx < nr_clk; idx++, list++) {
184 clk_hw = clk_hw_register_mux(ctx->dev, list->name,
185 list->parent_names, list->num_parents, list->flags,
186 ctx->reg_base + list->offset,
187 list->shift, list->width, list->mux_flags, &ctx->lock);
188 if (IS_ERR(clk_hw)) {
189 pr_err("%s: failed to register clock %s\n", __func__,
190 list->name);
191 continue;
192 }
193
194 samsung_clk_add_lookup(ctx, clk_hw, list->id);
195 }
196 }
197
198 /* register a list of div clocks */
samsung_clk_register_div(struct samsung_clk_provider * ctx,const struct samsung_div_clock * list,unsigned int nr_clk)199 void __init samsung_clk_register_div(struct samsung_clk_provider *ctx,
200 const struct samsung_div_clock *list,
201 unsigned int nr_clk)
202 {
203 struct clk_hw *clk_hw;
204 unsigned int idx;
205
206 for (idx = 0; idx < nr_clk; idx++, list++) {
207 if (list->table)
208 clk_hw = clk_hw_register_divider_table(ctx->dev,
209 list->name, list->parent_name, list->flags,
210 ctx->reg_base + list->offset,
211 list->shift, list->width, list->div_flags,
212 list->table, &ctx->lock);
213 else
214 clk_hw = clk_hw_register_divider(ctx->dev, list->name,
215 list->parent_name, list->flags,
216 ctx->reg_base + list->offset, list->shift,
217 list->width, list->div_flags, &ctx->lock);
218 if (IS_ERR(clk_hw)) {
219 pr_err("%s: failed to register clock %s\n", __func__,
220 list->name);
221 continue;
222 }
223
224 samsung_clk_add_lookup(ctx, clk_hw, list->id);
225 }
226 }
227
228 /* register a list of gate clocks */
samsung_clk_register_gate(struct samsung_clk_provider * ctx,const struct samsung_gate_clock * list,unsigned int nr_clk)229 void __init samsung_clk_register_gate(struct samsung_clk_provider *ctx,
230 const struct samsung_gate_clock *list,
231 unsigned int nr_clk)
232 {
233 struct clk_hw *clk_hw;
234 unsigned int idx;
235
236 for (idx = 0; idx < nr_clk; idx++, list++) {
237 clk_hw = clk_hw_register_gate(ctx->dev, list->name, list->parent_name,
238 list->flags, ctx->reg_base + list->offset,
239 list->bit_idx, list->gate_flags, &ctx->lock);
240 if (IS_ERR(clk_hw)) {
241 pr_err("%s: failed to register clock %s\n", __func__,
242 list->name);
243 continue;
244 }
245
246 samsung_clk_add_lookup(ctx, clk_hw, list->id);
247 }
248 }
249
250 /*
251 * obtain the clock speed of all external fixed clock sources from device
252 * tree and register it
253 */
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)254 void __init samsung_clk_of_register_fixed_ext(struct samsung_clk_provider *ctx,
255 struct samsung_fixed_rate_clock *fixed_rate_clk,
256 unsigned int nr_fixed_rate_clk,
257 const struct of_device_id *clk_matches)
258 {
259 const struct of_device_id *match;
260 struct device_node *clk_np;
261 u32 freq;
262
263 for_each_matching_node_and_match(clk_np, clk_matches, &match) {
264 if (of_property_read_u32(clk_np, "clock-frequency", &freq))
265 continue;
266 fixed_rate_clk[(unsigned long)match->data].fixed_rate = freq;
267 }
268 samsung_clk_register_fixed_rate(ctx, fixed_rate_clk, nr_fixed_rate_clk);
269 }
270
271 #ifdef CONFIG_PM_SLEEP
samsung_clk_suspend(void)272 static int samsung_clk_suspend(void)
273 {
274 struct samsung_clock_reg_cache *reg_cache;
275
276 list_for_each_entry(reg_cache, &clock_reg_cache_list, node) {
277 samsung_clk_save(reg_cache->reg_base, reg_cache->rdump,
278 reg_cache->rd_num);
279 samsung_clk_restore(reg_cache->reg_base, reg_cache->rsuspend,
280 reg_cache->rsuspend_num);
281 }
282 return 0;
283 }
284
samsung_clk_resume(void)285 static void samsung_clk_resume(void)
286 {
287 struct samsung_clock_reg_cache *reg_cache;
288
289 list_for_each_entry(reg_cache, &clock_reg_cache_list, node)
290 samsung_clk_restore(reg_cache->reg_base, reg_cache->rdump,
291 reg_cache->rd_num);
292 }
293
294 static struct syscore_ops samsung_clk_syscore_ops = {
295 .suspend = samsung_clk_suspend,
296 .resume = samsung_clk_resume,
297 };
298
samsung_clk_extended_sleep_init(void __iomem * reg_base,const unsigned long * rdump,unsigned long nr_rdump,const struct samsung_clk_reg_dump * rsuspend,unsigned long nr_rsuspend)299 void samsung_clk_extended_sleep_init(void __iomem *reg_base,
300 const unsigned long *rdump,
301 unsigned long nr_rdump,
302 const struct samsung_clk_reg_dump *rsuspend,
303 unsigned long nr_rsuspend)
304 {
305 struct samsung_clock_reg_cache *reg_cache;
306
307 reg_cache = kzalloc(sizeof(struct samsung_clock_reg_cache),
308 GFP_KERNEL);
309 if (!reg_cache)
310 panic("could not allocate register reg_cache.\n");
311 reg_cache->rdump = samsung_clk_alloc_reg_dump(rdump, nr_rdump);
312
313 if (!reg_cache->rdump)
314 panic("could not allocate register dump storage.\n");
315
316 if (list_empty(&clock_reg_cache_list))
317 register_syscore_ops(&samsung_clk_syscore_ops);
318
319 reg_cache->reg_base = reg_base;
320 reg_cache->rd_num = nr_rdump;
321 reg_cache->rsuspend = rsuspend;
322 reg_cache->rsuspend_num = nr_rsuspend;
323 list_add_tail(®_cache->node, &clock_reg_cache_list);
324 }
325 #endif
326
327 /*
328 * Common function which registers plls, muxes, dividers and gates
329 * for each CMU. It also add CMU register list to register cache.
330 */
samsung_cmu_register_one(struct device_node * np,const struct samsung_cmu_info * cmu)331 struct samsung_clk_provider * __init samsung_cmu_register_one(
332 struct device_node *np,
333 const struct samsung_cmu_info *cmu)
334 {
335 void __iomem *reg_base;
336 struct samsung_clk_provider *ctx;
337
338 reg_base = of_iomap(np, 0);
339 if (!reg_base) {
340 panic("%s: failed to map registers\n", __func__);
341 return NULL;
342 }
343
344 ctx = samsung_clk_init(np, reg_base, cmu->nr_clk_ids);
345
346 if (cmu->pll_clks)
347 samsung_clk_register_pll(ctx, cmu->pll_clks, cmu->nr_pll_clks,
348 reg_base);
349 if (cmu->mux_clks)
350 samsung_clk_register_mux(ctx, cmu->mux_clks,
351 cmu->nr_mux_clks);
352 if (cmu->div_clks)
353 samsung_clk_register_div(ctx, cmu->div_clks, cmu->nr_div_clks);
354 if (cmu->gate_clks)
355 samsung_clk_register_gate(ctx, cmu->gate_clks,
356 cmu->nr_gate_clks);
357 if (cmu->fixed_clks)
358 samsung_clk_register_fixed_rate(ctx, cmu->fixed_clks,
359 cmu->nr_fixed_clks);
360 if (cmu->fixed_factor_clks)
361 samsung_clk_register_fixed_factor(ctx, cmu->fixed_factor_clks,
362 cmu->nr_fixed_factor_clks);
363 if (cmu->clk_regs)
364 samsung_clk_extended_sleep_init(reg_base,
365 cmu->clk_regs, cmu->nr_clk_regs,
366 cmu->suspend_regs, cmu->nr_suspend_regs);
367 if (cmu->cpu_clks)
368 samsung_clk_register_cpu(ctx, cmu->cpu_clks, cmu->nr_cpu_clks);
369
370 samsung_clk_of_add_provider(np, ctx);
371
372 return ctx;
373 }
374