1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * PRCMU clock implementation for ux500 platform.
4 *
5 * Copyright (C) 2012 ST-Ericsson SA
6 * Author: Ulf Hansson <ulf.hansson@linaro.org>
7 */
8
9#include <linux/clk-provider.h>
10#include <linux/mfd/dbx500-prcmu.h>
11#include <linux/slab.h>
12#include <linux/io.h>
13#include <linux/err.h>
14#include "clk.h"
15
16#define to_clk_prcmu(_hw) container_of(_hw, struct clk_prcmu, hw)
17#define to_clk_prcmu_clkout(_hw) container_of(_hw, struct clk_prcmu_clkout, hw)
18
19struct clk_prcmu {
20 struct clk_hw hw;
21 u8 cg_sel;
22 int opp_requested;
23};
24
25struct clk_prcmu_clkout {
26 struct clk_hw hw;
27 u8 clkout_id;
28 u8 source;
29 u8 divider;
30};
31
32/* PRCMU clock operations. */
33
34static int clk_prcmu_prepare(struct clk_hw *hw)
35{
36 struct clk_prcmu *clk = to_clk_prcmu(hw);
37
38 return prcmu_request_clock(clock: clk->cg_sel, enable: true);
39}
40
41static void clk_prcmu_unprepare(struct clk_hw *hw)
42{
43 struct clk_prcmu *clk = to_clk_prcmu(hw);
44 if (prcmu_request_clock(clock: clk->cg_sel, enable: false))
45 pr_err("clk_prcmu: %s failed to disable %s.\n", __func__,
46 clk_hw_get_name(hw));
47}
48
49static unsigned long clk_prcmu_recalc_rate(struct clk_hw *hw,
50 unsigned long parent_rate)
51{
52 struct clk_prcmu *clk = to_clk_prcmu(hw);
53 return prcmu_clock_rate(clock: clk->cg_sel);
54}
55
56static long clk_prcmu_round_rate(struct clk_hw *hw, unsigned long rate,
57 unsigned long *parent_rate)
58{
59 struct clk_prcmu *clk = to_clk_prcmu(hw);
60 return prcmu_round_clock_rate(clock: clk->cg_sel, rate);
61}
62
63static int clk_prcmu_set_rate(struct clk_hw *hw, unsigned long rate,
64 unsigned long parent_rate)
65{
66 struct clk_prcmu *clk = to_clk_prcmu(hw);
67 return prcmu_set_clock_rate(clock: clk->cg_sel, rate);
68}
69
70static int clk_prcmu_opp_prepare(struct clk_hw *hw)
71{
72 int err;
73 struct clk_prcmu *clk = to_clk_prcmu(hw);
74
75 if (!clk->opp_requested) {
76 err = prcmu_qos_add_requirement(PRCMU_QOS_APE_OPP,
77 name: (char *)clk_hw_get_name(hw),
78 value: 100);
79 if (err) {
80 pr_err("clk_prcmu: %s fail req APE OPP for %s.\n",
81 __func__, clk_hw_get_name(hw));
82 return err;
83 }
84 clk->opp_requested = 1;
85 }
86
87 err = prcmu_request_clock(clock: clk->cg_sel, enable: true);
88 if (err) {
89 prcmu_qos_remove_requirement(PRCMU_QOS_APE_OPP,
90 name: (char *)clk_hw_get_name(hw));
91 clk->opp_requested = 0;
92 return err;
93 }
94
95 return 0;
96}
97
98static void clk_prcmu_opp_unprepare(struct clk_hw *hw)
99{
100 struct clk_prcmu *clk = to_clk_prcmu(hw);
101
102 if (prcmu_request_clock(clock: clk->cg_sel, enable: false)) {
103 pr_err("clk_prcmu: %s failed to disable %s.\n", __func__,
104 clk_hw_get_name(hw));
105 return;
106 }
107
108 if (clk->opp_requested) {
109 prcmu_qos_remove_requirement(PRCMU_QOS_APE_OPP,
110 name: (char *)clk_hw_get_name(hw));
111 clk->opp_requested = 0;
112 }
113}
114
115static int clk_prcmu_opp_volt_prepare(struct clk_hw *hw)
116{
117 int err;
118 struct clk_prcmu *clk = to_clk_prcmu(hw);
119
120 if (!clk->opp_requested) {
121 err = prcmu_request_ape_opp_100_voltage(enable: true);
122 if (err) {
123 pr_err("clk_prcmu: %s fail req APE OPP VOLT for %s.\n",
124 __func__, clk_hw_get_name(hw));
125 return err;
126 }
127 clk->opp_requested = 1;
128 }
129
130 err = prcmu_request_clock(clock: clk->cg_sel, enable: true);
131 if (err) {
132 prcmu_request_ape_opp_100_voltage(enable: false);
133 clk->opp_requested = 0;
134 return err;
135 }
136
137 return 0;
138}
139
140static void clk_prcmu_opp_volt_unprepare(struct clk_hw *hw)
141{
142 struct clk_prcmu *clk = to_clk_prcmu(hw);
143
144 if (prcmu_request_clock(clock: clk->cg_sel, enable: false)) {
145 pr_err("clk_prcmu: %s failed to disable %s.\n", __func__,
146 clk_hw_get_name(hw));
147 return;
148 }
149
150 if (clk->opp_requested) {
151 prcmu_request_ape_opp_100_voltage(enable: false);
152 clk->opp_requested = 0;
153 }
154}
155
156static const struct clk_ops clk_prcmu_scalable_ops = {
157 .prepare = clk_prcmu_prepare,
158 .unprepare = clk_prcmu_unprepare,
159 .recalc_rate = clk_prcmu_recalc_rate,
160 .round_rate = clk_prcmu_round_rate,
161 .set_rate = clk_prcmu_set_rate,
162};
163
164static const struct clk_ops clk_prcmu_gate_ops = {
165 .prepare = clk_prcmu_prepare,
166 .unprepare = clk_prcmu_unprepare,
167 .recalc_rate = clk_prcmu_recalc_rate,
168};
169
170static const struct clk_ops clk_prcmu_scalable_rate_ops = {
171 .recalc_rate = clk_prcmu_recalc_rate,
172 .round_rate = clk_prcmu_round_rate,
173 .set_rate = clk_prcmu_set_rate,
174};
175
176static const struct clk_ops clk_prcmu_rate_ops = {
177 .recalc_rate = clk_prcmu_recalc_rate,
178};
179
180static const struct clk_ops clk_prcmu_opp_gate_ops = {
181 .prepare = clk_prcmu_opp_prepare,
182 .unprepare = clk_prcmu_opp_unprepare,
183 .recalc_rate = clk_prcmu_recalc_rate,
184};
185
186static const struct clk_ops clk_prcmu_opp_volt_scalable_ops = {
187 .prepare = clk_prcmu_opp_volt_prepare,
188 .unprepare = clk_prcmu_opp_volt_unprepare,
189 .recalc_rate = clk_prcmu_recalc_rate,
190 .round_rate = clk_prcmu_round_rate,
191 .set_rate = clk_prcmu_set_rate,
192};
193
194static struct clk_hw *clk_reg_prcmu(const char *name,
195 const char *parent_name,
196 u8 cg_sel,
197 unsigned long rate,
198 unsigned long flags,
199 const struct clk_ops *clk_prcmu_ops)
200{
201 struct clk_prcmu *clk;
202 struct clk_init_data clk_prcmu_init;
203 int ret;
204
205 if (!name) {
206 pr_err("clk_prcmu: %s invalid arguments passed\n", __func__);
207 return ERR_PTR(error: -EINVAL);
208 }
209
210 clk = kzalloc(size: sizeof(*clk), GFP_KERNEL);
211 if (!clk)
212 return ERR_PTR(error: -ENOMEM);
213
214 clk->cg_sel = cg_sel;
215 clk->opp_requested = 0;
216 /* "rate" can be used for changing the initial frequency */
217 if (rate)
218 prcmu_set_clock_rate(clock: cg_sel, rate);
219
220 clk_prcmu_init.name = name;
221 clk_prcmu_init.ops = clk_prcmu_ops;
222 clk_prcmu_init.flags = flags;
223 clk_prcmu_init.parent_names = (parent_name ? &parent_name : NULL);
224 clk_prcmu_init.num_parents = (parent_name ? 1 : 0);
225 clk->hw.init = &clk_prcmu_init;
226
227 ret = clk_hw_register(NULL, hw: &clk->hw);
228 if (ret)
229 goto free_clk;
230
231 return &clk->hw;
232
233free_clk:
234 kfree(objp: clk);
235 pr_err("clk_prcmu: %s failed to register clk\n", __func__);
236 return ERR_PTR(error: -ENOMEM);
237}
238
239struct clk_hw *clk_reg_prcmu_scalable(const char *name,
240 const char *parent_name,
241 u8 cg_sel,
242 unsigned long rate,
243 unsigned long flags)
244{
245 return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags,
246 clk_prcmu_ops: &clk_prcmu_scalable_ops);
247}
248
249struct clk_hw *clk_reg_prcmu_gate(const char *name,
250 const char *parent_name,
251 u8 cg_sel,
252 unsigned long flags)
253{
254 return clk_reg_prcmu(name, parent_name, cg_sel, rate: 0, flags,
255 clk_prcmu_ops: &clk_prcmu_gate_ops);
256}
257
258struct clk_hw *clk_reg_prcmu_scalable_rate(const char *name,
259 const char *parent_name,
260 u8 cg_sel,
261 unsigned long rate,
262 unsigned long flags)
263{
264 return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags,
265 clk_prcmu_ops: &clk_prcmu_scalable_rate_ops);
266}
267
268struct clk_hw *clk_reg_prcmu_rate(const char *name,
269 const char *parent_name,
270 u8 cg_sel,
271 unsigned long flags)
272{
273 return clk_reg_prcmu(name, parent_name, cg_sel, rate: 0, flags,
274 clk_prcmu_ops: &clk_prcmu_rate_ops);
275}
276
277struct clk_hw *clk_reg_prcmu_opp_gate(const char *name,
278 const char *parent_name,
279 u8 cg_sel,
280 unsigned long flags)
281{
282 return clk_reg_prcmu(name, parent_name, cg_sel, rate: 0, flags,
283 clk_prcmu_ops: &clk_prcmu_opp_gate_ops);
284}
285
286struct clk_hw *clk_reg_prcmu_opp_volt_scalable(const char *name,
287 const char *parent_name,
288 u8 cg_sel,
289 unsigned long rate,
290 unsigned long flags)
291{
292 return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags,
293 clk_prcmu_ops: &clk_prcmu_opp_volt_scalable_ops);
294}
295
296/* The clkout (external) clock is special and need special ops */
297
298static int clk_prcmu_clkout_prepare(struct clk_hw *hw)
299{
300 struct clk_prcmu_clkout *clk = to_clk_prcmu_clkout(hw);
301
302 return prcmu_config_clkout(clk->clkout_id, clk->source, clk->divider);
303}
304
305static void clk_prcmu_clkout_unprepare(struct clk_hw *hw)
306{
307 struct clk_prcmu_clkout *clk = to_clk_prcmu_clkout(hw);
308 int ret;
309
310 /* The clkout clock is disabled by dividing by 0 */
311 ret = prcmu_config_clkout(clk->clkout_id, clk->source, 0);
312 if (ret)
313 pr_err("clk_prcmu: %s failed to disable %s\n", __func__,
314 clk_hw_get_name(hw));
315}
316
317static unsigned long clk_prcmu_clkout_recalc_rate(struct clk_hw *hw,
318 unsigned long parent_rate)
319{
320 struct clk_prcmu_clkout *clk = to_clk_prcmu_clkout(hw);
321
322 return (parent_rate / clk->divider);
323}
324
325static u8 clk_prcmu_clkout_get_parent(struct clk_hw *hw)
326{
327 struct clk_prcmu_clkout *clk = to_clk_prcmu_clkout(hw);
328
329 return clk->source;
330}
331
332static int clk_prcmu_clkout_set_parent(struct clk_hw *hw, u8 index)
333{
334 struct clk_prcmu_clkout *clk = to_clk_prcmu_clkout(hw);
335
336 clk->source = index;
337 /* Make sure the change reaches the hardware immediately */
338 if (clk_hw_is_prepared(hw))
339 return clk_prcmu_clkout_prepare(hw);
340 return 0;
341}
342
343static const struct clk_ops clk_prcmu_clkout_ops = {
344 .prepare = clk_prcmu_clkout_prepare,
345 .unprepare = clk_prcmu_clkout_unprepare,
346 .recalc_rate = clk_prcmu_clkout_recalc_rate,
347 .determine_rate = clk_hw_determine_rate_no_reparent,
348 .get_parent = clk_prcmu_clkout_get_parent,
349 .set_parent = clk_prcmu_clkout_set_parent,
350};
351
352struct clk_hw *clk_reg_prcmu_clkout(const char *name,
353 const char * const *parent_names,
354 int num_parents,
355 u8 source, u8 divider)
356
357{
358 struct clk_prcmu_clkout *clk;
359 struct clk_init_data clk_prcmu_clkout_init;
360 u8 clkout_id;
361 int ret;
362
363 if (!name) {
364 pr_err("clk_prcmu_clkout: %s invalid arguments passed\n", __func__);
365 return ERR_PTR(error: -EINVAL);
366 }
367
368 if (!strcmp(name, "clkout1"))
369 clkout_id = 0;
370 else if (!strcmp(name, "clkout2"))
371 clkout_id = 1;
372 else {
373 pr_err("clk_prcmu_clkout: %s bad clock name\n", __func__);
374 return ERR_PTR(error: -EINVAL);
375 }
376
377 clk = kzalloc(size: sizeof(*clk), GFP_KERNEL);
378 if (!clk)
379 return ERR_PTR(error: -ENOMEM);
380
381 clk->clkout_id = clkout_id;
382 clk->source = source;
383 clk->divider = divider;
384
385 clk_prcmu_clkout_init.name = name;
386 clk_prcmu_clkout_init.ops = &clk_prcmu_clkout_ops;
387 clk_prcmu_clkout_init.flags = CLK_GET_RATE_NOCACHE;
388 clk_prcmu_clkout_init.parent_names = parent_names;
389 clk_prcmu_clkout_init.num_parents = num_parents;
390 clk->hw.init = &clk_prcmu_clkout_init;
391
392 ret = clk_hw_register(NULL, hw: &clk->hw);
393 if (ret)
394 goto free_clkout;
395
396 return &clk->hw;
397free_clkout:
398 kfree(objp: clk);
399 pr_err("clk_prcmu_clkout: %s failed to register clk\n", __func__);
400 return ERR_PTR(error: -ENOMEM);
401}
402

source code of linux/drivers/clk/ux500/clk-prcmu.c