xref: /openbmc/linux/drivers/clk/qcom/common.c (revision 8730046c)
1 /*
2  * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
3  *
4  * This software is licensed under the terms of the GNU General Public
5  * License version 2, as published by the Free Software Foundation, and
6  * may be copied, distributed, and modified under those terms.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 #include <linux/export.h>
15 #include <linux/module.h>
16 #include <linux/regmap.h>
17 #include <linux/platform_device.h>
18 #include <linux/clk-provider.h>
19 #include <linux/reset-controller.h>
20 #include <linux/of.h>
21 
22 #include "common.h"
23 #include "clk-rcg.h"
24 #include "clk-regmap.h"
25 #include "reset.h"
26 #include "gdsc.h"
27 
28 struct qcom_cc {
29 	struct qcom_reset_controller reset;
30 	struct clk_regmap **rclks;
31 	size_t num_rclks;
32 };
33 
34 const
35 struct freq_tbl *qcom_find_freq(const struct freq_tbl *f, unsigned long rate)
36 {
37 	if (!f)
38 		return NULL;
39 
40 	for (; f->freq; f++)
41 		if (rate <= f->freq)
42 			return f;
43 
44 	/* Default to our fastest rate */
45 	return f - 1;
46 }
47 EXPORT_SYMBOL_GPL(qcom_find_freq);
48 
49 const struct freq_tbl *qcom_find_freq_floor(const struct freq_tbl *f,
50 					    unsigned long rate)
51 {
52 	const struct freq_tbl *best = NULL;
53 
54 	for ( ; f->freq; f++) {
55 		if (rate >= f->freq)
56 			best = f;
57 		else
58 			break;
59 	}
60 
61 	return best;
62 }
63 EXPORT_SYMBOL_GPL(qcom_find_freq_floor);
64 
65 int qcom_find_src_index(struct clk_hw *hw, const struct parent_map *map, u8 src)
66 {
67 	int i, num_parents = clk_hw_get_num_parents(hw);
68 
69 	for (i = 0; i < num_parents; i++)
70 		if (src == map[i].src)
71 			return i;
72 
73 	return -ENOENT;
74 }
75 EXPORT_SYMBOL_GPL(qcom_find_src_index);
76 
77 struct regmap *
78 qcom_cc_map(struct platform_device *pdev, const struct qcom_cc_desc *desc)
79 {
80 	void __iomem *base;
81 	struct resource *res;
82 	struct device *dev = &pdev->dev;
83 
84 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
85 	base = devm_ioremap_resource(dev, res);
86 	if (IS_ERR(base))
87 		return ERR_CAST(base);
88 
89 	return devm_regmap_init_mmio(dev, base, desc->config);
90 }
91 EXPORT_SYMBOL_GPL(qcom_cc_map);
92 
93 void
94 qcom_pll_set_fsm_mode(struct regmap *map, u32 reg, u8 bias_count, u8 lock_count)
95 {
96 	u32 val;
97 	u32 mask;
98 
99 	/* De-assert reset to FSM */
100 	regmap_update_bits(map, reg, PLL_VOTE_FSM_RESET, 0);
101 
102 	/* Program bias count and lock count */
103 	val = bias_count << PLL_BIAS_COUNT_SHIFT |
104 		lock_count << PLL_LOCK_COUNT_SHIFT;
105 	mask = PLL_BIAS_COUNT_MASK << PLL_BIAS_COUNT_SHIFT;
106 	mask |= PLL_LOCK_COUNT_MASK << PLL_LOCK_COUNT_SHIFT;
107 	regmap_update_bits(map, reg, mask, val);
108 
109 	/* Enable PLL FSM voting */
110 	regmap_update_bits(map, reg, PLL_VOTE_FSM_ENA, PLL_VOTE_FSM_ENA);
111 }
112 EXPORT_SYMBOL_GPL(qcom_pll_set_fsm_mode);
113 
114 static void qcom_cc_del_clk_provider(void *data)
115 {
116 	of_clk_del_provider(data);
117 }
118 
119 static void qcom_cc_reset_unregister(void *data)
120 {
121 	reset_controller_unregister(data);
122 }
123 
124 static void qcom_cc_gdsc_unregister(void *data)
125 {
126 	gdsc_unregister(data);
127 }
128 
129 /*
130  * Backwards compatibility with old DTs. Register a pass-through factor 1/1
131  * clock to translate 'path' clk into 'name' clk and regsiter the 'path'
132  * clk as a fixed rate clock if it isn't present.
133  */
134 static int _qcom_cc_register_board_clk(struct device *dev, const char *path,
135 				       const char *name, unsigned long rate,
136 				       bool add_factor)
137 {
138 	struct device_node *node = NULL;
139 	struct device_node *clocks_node;
140 	struct clk_fixed_factor *factor;
141 	struct clk_fixed_rate *fixed;
142 	struct clk_init_data init_data = { };
143 	int ret;
144 
145 	clocks_node = of_find_node_by_path("/clocks");
146 	if (clocks_node)
147 		node = of_find_node_by_name(clocks_node, path);
148 	of_node_put(clocks_node);
149 
150 	if (!node) {
151 		fixed = devm_kzalloc(dev, sizeof(*fixed), GFP_KERNEL);
152 		if (!fixed)
153 			return -EINVAL;
154 
155 		fixed->fixed_rate = rate;
156 		fixed->hw.init = &init_data;
157 
158 		init_data.name = path;
159 		init_data.ops = &clk_fixed_rate_ops;
160 
161 		ret = devm_clk_hw_register(dev, &fixed->hw);
162 		if (ret)
163 			return ret;
164 	}
165 	of_node_put(node);
166 
167 	if (add_factor) {
168 		factor = devm_kzalloc(dev, sizeof(*factor), GFP_KERNEL);
169 		if (!factor)
170 			return -EINVAL;
171 
172 		factor->mult = factor->div = 1;
173 		factor->hw.init = &init_data;
174 
175 		init_data.name = name;
176 		init_data.parent_names = &path;
177 		init_data.num_parents = 1;
178 		init_data.flags = 0;
179 		init_data.ops = &clk_fixed_factor_ops;
180 
181 		ret = devm_clk_hw_register(dev, &factor->hw);
182 		if (ret)
183 			return ret;
184 	}
185 
186 	return 0;
187 }
188 
189 int qcom_cc_register_board_clk(struct device *dev, const char *path,
190 			       const char *name, unsigned long rate)
191 {
192 	bool add_factor = true;
193 
194 	/*
195 	 * TODO: The RPM clock driver currently does not support the xo clock.
196 	 * When xo is added to the RPM clock driver, we should change this
197 	 * function to skip registration of xo factor clocks.
198 	 */
199 
200 	return _qcom_cc_register_board_clk(dev, path, name, rate, add_factor);
201 }
202 EXPORT_SYMBOL_GPL(qcom_cc_register_board_clk);
203 
204 int qcom_cc_register_sleep_clk(struct device *dev)
205 {
206 	return _qcom_cc_register_board_clk(dev, "sleep_clk", "sleep_clk_src",
207 					   32768, true);
208 }
209 EXPORT_SYMBOL_GPL(qcom_cc_register_sleep_clk);
210 
211 static struct clk_hw *qcom_cc_clk_hw_get(struct of_phandle_args *clkspec,
212 					 void *data)
213 {
214 	struct qcom_cc *cc = data;
215 	unsigned int idx = clkspec->args[0];
216 
217 	if (idx >= cc->num_rclks) {
218 		pr_err("%s: invalid index %u\n", __func__, idx);
219 		return ERR_PTR(-EINVAL);
220 	}
221 
222 	return cc->rclks[idx] ? &cc->rclks[idx]->hw : ERR_PTR(-ENOENT);
223 }
224 
225 int qcom_cc_really_probe(struct platform_device *pdev,
226 			 const struct qcom_cc_desc *desc, struct regmap *regmap)
227 {
228 	int i, ret;
229 	struct device *dev = &pdev->dev;
230 	struct qcom_reset_controller *reset;
231 	struct qcom_cc *cc;
232 	struct gdsc_desc *scd;
233 	size_t num_clks = desc->num_clks;
234 	struct clk_regmap **rclks = desc->clks;
235 
236 	cc = devm_kzalloc(dev, sizeof(*cc), GFP_KERNEL);
237 	if (!cc)
238 		return -ENOMEM;
239 
240 	cc->rclks = rclks;
241 	cc->num_rclks = num_clks;
242 
243 	for (i = 0; i < num_clks; i++) {
244 		if (!rclks[i])
245 			continue;
246 
247 		ret = devm_clk_register_regmap(dev, rclks[i]);
248 		if (ret)
249 			return ret;
250 	}
251 
252 	ret = of_clk_add_hw_provider(dev->of_node, qcom_cc_clk_hw_get, cc);
253 	if (ret)
254 		return ret;
255 
256 	ret = devm_add_action_or_reset(dev, qcom_cc_del_clk_provider,
257 				       pdev->dev.of_node);
258 
259 	if (ret)
260 		return ret;
261 
262 	reset = &cc->reset;
263 	reset->rcdev.of_node = dev->of_node;
264 	reset->rcdev.ops = &qcom_reset_ops;
265 	reset->rcdev.owner = dev->driver->owner;
266 	reset->rcdev.nr_resets = desc->num_resets;
267 	reset->regmap = regmap;
268 	reset->reset_map = desc->resets;
269 
270 	ret = reset_controller_register(&reset->rcdev);
271 	if (ret)
272 		return ret;
273 
274 	ret = devm_add_action_or_reset(dev, qcom_cc_reset_unregister,
275 				       &reset->rcdev);
276 
277 	if (ret)
278 		return ret;
279 
280 	if (desc->gdscs && desc->num_gdscs) {
281 		scd = devm_kzalloc(dev, sizeof(*scd), GFP_KERNEL);
282 		if (!scd)
283 			return -ENOMEM;
284 		scd->dev = dev;
285 		scd->scs = desc->gdscs;
286 		scd->num = desc->num_gdscs;
287 		ret = gdsc_register(scd, &reset->rcdev, regmap);
288 		if (ret)
289 			return ret;
290 		ret = devm_add_action_or_reset(dev, qcom_cc_gdsc_unregister,
291 					       scd);
292 		if (ret)
293 			return ret;
294 	}
295 
296 	return 0;
297 }
298 EXPORT_SYMBOL_GPL(qcom_cc_really_probe);
299 
300 int qcom_cc_probe(struct platform_device *pdev, const struct qcom_cc_desc *desc)
301 {
302 	struct regmap *regmap;
303 
304 	regmap = qcom_cc_map(pdev, desc);
305 	if (IS_ERR(regmap))
306 		return PTR_ERR(regmap);
307 
308 	return qcom_cc_really_probe(pdev, desc, regmap);
309 }
310 EXPORT_SYMBOL_GPL(qcom_cc_probe);
311 
312 MODULE_LICENSE("GPL v2");
313