xref: /linux/drivers/clk/qcom/common.c (revision 856e7c4b619af622d56b3b454f7bec32a170ac99)
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_gdsc_unregister(void *data)
115 {
116 	gdsc_unregister(data);
117 }
118 
119 /*
120  * Backwards compatibility with old DTs. Register a pass-through factor 1/1
121  * clock to translate 'path' clk into 'name' clk and register the 'path'
122  * clk as a fixed rate clock if it isn't present.
123  */
124 static int _qcom_cc_register_board_clk(struct device *dev, const char *path,
125 				       const char *name, unsigned long rate,
126 				       bool add_factor)
127 {
128 	struct device_node *node = NULL;
129 	struct device_node *clocks_node;
130 	struct clk_fixed_factor *factor;
131 	struct clk_fixed_rate *fixed;
132 	struct clk_init_data init_data = { };
133 	int ret;
134 
135 	clocks_node = of_find_node_by_path("/clocks");
136 	if (clocks_node) {
137 		node = of_get_child_by_name(clocks_node, path);
138 		of_node_put(clocks_node);
139 	}
140 
141 	if (!node) {
142 		fixed = devm_kzalloc(dev, sizeof(*fixed), GFP_KERNEL);
143 		if (!fixed)
144 			return -EINVAL;
145 
146 		fixed->fixed_rate = rate;
147 		fixed->hw.init = &init_data;
148 
149 		init_data.name = path;
150 		init_data.ops = &clk_fixed_rate_ops;
151 
152 		ret = devm_clk_hw_register(dev, &fixed->hw);
153 		if (ret)
154 			return ret;
155 	}
156 	of_node_put(node);
157 
158 	if (add_factor) {
159 		factor = devm_kzalloc(dev, sizeof(*factor), GFP_KERNEL);
160 		if (!factor)
161 			return -EINVAL;
162 
163 		factor->mult = factor->div = 1;
164 		factor->hw.init = &init_data;
165 
166 		init_data.name = name;
167 		init_data.parent_names = &path;
168 		init_data.num_parents = 1;
169 		init_data.flags = 0;
170 		init_data.ops = &clk_fixed_factor_ops;
171 
172 		ret = devm_clk_hw_register(dev, &factor->hw);
173 		if (ret)
174 			return ret;
175 	}
176 
177 	return 0;
178 }
179 
180 int qcom_cc_register_board_clk(struct device *dev, const char *path,
181 			       const char *name, unsigned long rate)
182 {
183 	bool add_factor = true;
184 
185 	/*
186 	 * TODO: The RPM clock driver currently does not support the xo clock.
187 	 * When xo is added to the RPM clock driver, we should change this
188 	 * function to skip registration of xo factor clocks.
189 	 */
190 
191 	return _qcom_cc_register_board_clk(dev, path, name, rate, add_factor);
192 }
193 EXPORT_SYMBOL_GPL(qcom_cc_register_board_clk);
194 
195 int qcom_cc_register_sleep_clk(struct device *dev)
196 {
197 	return _qcom_cc_register_board_clk(dev, "sleep_clk", "sleep_clk_src",
198 					   32768, true);
199 }
200 EXPORT_SYMBOL_GPL(qcom_cc_register_sleep_clk);
201 
202 static struct clk_hw *qcom_cc_clk_hw_get(struct of_phandle_args *clkspec,
203 					 void *data)
204 {
205 	struct qcom_cc *cc = data;
206 	unsigned int idx = clkspec->args[0];
207 
208 	if (idx >= cc->num_rclks) {
209 		pr_err("%s: invalid index %u\n", __func__, idx);
210 		return ERR_PTR(-EINVAL);
211 	}
212 
213 	return cc->rclks[idx] ? &cc->rclks[idx]->hw : ERR_PTR(-ENOENT);
214 }
215 
216 int qcom_cc_really_probe(struct platform_device *pdev,
217 			 const struct qcom_cc_desc *desc, struct regmap *regmap)
218 {
219 	int i, ret;
220 	struct device *dev = &pdev->dev;
221 	struct qcom_reset_controller *reset;
222 	struct qcom_cc *cc;
223 	struct gdsc_desc *scd;
224 	size_t num_clks = desc->num_clks;
225 	struct clk_regmap **rclks = desc->clks;
226 
227 	cc = devm_kzalloc(dev, sizeof(*cc), GFP_KERNEL);
228 	if (!cc)
229 		return -ENOMEM;
230 
231 	reset = &cc->reset;
232 	reset->rcdev.of_node = dev->of_node;
233 	reset->rcdev.ops = &qcom_reset_ops;
234 	reset->rcdev.owner = dev->driver->owner;
235 	reset->rcdev.nr_resets = desc->num_resets;
236 	reset->regmap = regmap;
237 	reset->reset_map = desc->resets;
238 
239 	ret = devm_reset_controller_register(dev, &reset->rcdev);
240 	if (ret)
241 		return ret;
242 
243 	if (desc->gdscs && desc->num_gdscs) {
244 		scd = devm_kzalloc(dev, sizeof(*scd), GFP_KERNEL);
245 		if (!scd)
246 			return -ENOMEM;
247 		scd->dev = dev;
248 		scd->scs = desc->gdscs;
249 		scd->num = desc->num_gdscs;
250 		ret = gdsc_register(scd, &reset->rcdev, regmap);
251 		if (ret)
252 			return ret;
253 		ret = devm_add_action_or_reset(dev, qcom_cc_gdsc_unregister,
254 					       scd);
255 		if (ret)
256 			return ret;
257 	}
258 
259 	cc->rclks = rclks;
260 	cc->num_rclks = num_clks;
261 
262 	for (i = 0; i < num_clks; i++) {
263 		if (!rclks[i])
264 			continue;
265 
266 		ret = devm_clk_register_regmap(dev, rclks[i]);
267 		if (ret)
268 			return ret;
269 	}
270 
271 	ret = devm_of_clk_add_hw_provider(dev, qcom_cc_clk_hw_get, cc);
272 	if (ret)
273 		return ret;
274 
275 	return 0;
276 }
277 EXPORT_SYMBOL_GPL(qcom_cc_really_probe);
278 
279 int qcom_cc_probe(struct platform_device *pdev, const struct qcom_cc_desc *desc)
280 {
281 	struct regmap *regmap;
282 
283 	regmap = qcom_cc_map(pdev, desc);
284 	if (IS_ERR(regmap))
285 		return PTR_ERR(regmap);
286 
287 	return qcom_cc_really_probe(pdev, desc, regmap);
288 }
289 EXPORT_SYMBOL_GPL(qcom_cc_probe);
290 
291 MODULE_LICENSE("GPL v2");
292