xref: /openbmc/linux/drivers/clk/qcom/common.c (revision 036b9e7c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/export.h>
7 #include <linux/module.h>
8 #include <linux/regmap.h>
9 #include <linux/platform_device.h>
10 #include <linux/clk-provider.h>
11 #include <linux/reset-controller.h>
12 #include <linux/of.h>
13 
14 #include "common.h"
15 #include "clk-rcg.h"
16 #include "clk-regmap.h"
17 #include "reset.h"
18 #include "gdsc.h"
19 
20 struct qcom_cc {
21 	struct qcom_reset_controller reset;
22 	struct clk_regmap **rclks;
23 	size_t num_rclks;
24 };
25 
26 const
27 struct freq_tbl *qcom_find_freq(const struct freq_tbl *f, unsigned long rate)
28 {
29 	if (!f)
30 		return NULL;
31 
32 	for (; f->freq; f++)
33 		if (rate <= f->freq)
34 			return f;
35 
36 	/* Default to our fastest rate */
37 	return f - 1;
38 }
39 EXPORT_SYMBOL_GPL(qcom_find_freq);
40 
41 const struct freq_tbl *qcom_find_freq_floor(const struct freq_tbl *f,
42 					    unsigned long rate)
43 {
44 	const struct freq_tbl *best = NULL;
45 
46 	for ( ; f->freq; f++) {
47 		if (rate >= f->freq)
48 			best = f;
49 		else
50 			break;
51 	}
52 
53 	return best;
54 }
55 EXPORT_SYMBOL_GPL(qcom_find_freq_floor);
56 
57 int qcom_find_src_index(struct clk_hw *hw, const struct parent_map *map, u8 src)
58 {
59 	int i, num_parents = clk_hw_get_num_parents(hw);
60 
61 	for (i = 0; i < num_parents; i++)
62 		if (src == map[i].src)
63 			return i;
64 
65 	return -ENOENT;
66 }
67 EXPORT_SYMBOL_GPL(qcom_find_src_index);
68 
69 struct regmap *
70 qcom_cc_map(struct platform_device *pdev, const struct qcom_cc_desc *desc)
71 {
72 	void __iomem *base;
73 	struct resource *res;
74 	struct device *dev = &pdev->dev;
75 
76 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
77 	base = devm_ioremap_resource(dev, res);
78 	if (IS_ERR(base))
79 		return ERR_CAST(base);
80 
81 	return devm_regmap_init_mmio(dev, base, desc->config);
82 }
83 EXPORT_SYMBOL_GPL(qcom_cc_map);
84 
85 void
86 qcom_pll_set_fsm_mode(struct regmap *map, u32 reg, u8 bias_count, u8 lock_count)
87 {
88 	u32 val;
89 	u32 mask;
90 
91 	/* De-assert reset to FSM */
92 	regmap_update_bits(map, reg, PLL_VOTE_FSM_RESET, 0);
93 
94 	/* Program bias count and lock count */
95 	val = bias_count << PLL_BIAS_COUNT_SHIFT |
96 		lock_count << PLL_LOCK_COUNT_SHIFT;
97 	mask = PLL_BIAS_COUNT_MASK << PLL_BIAS_COUNT_SHIFT;
98 	mask |= PLL_LOCK_COUNT_MASK << PLL_LOCK_COUNT_SHIFT;
99 	regmap_update_bits(map, reg, mask, val);
100 
101 	/* Enable PLL FSM voting */
102 	regmap_update_bits(map, reg, PLL_VOTE_FSM_ENA, PLL_VOTE_FSM_ENA);
103 }
104 EXPORT_SYMBOL_GPL(qcom_pll_set_fsm_mode);
105 
106 static void qcom_cc_gdsc_unregister(void *data)
107 {
108 	gdsc_unregister(data);
109 }
110 
111 /*
112  * Backwards compatibility with old DTs. Register a pass-through factor 1/1
113  * clock to translate 'path' clk into 'name' clk and register the 'path'
114  * clk as a fixed rate clock if it isn't present.
115  */
116 static int _qcom_cc_register_board_clk(struct device *dev, const char *path,
117 				       const char *name, unsigned long rate,
118 				       bool add_factor)
119 {
120 	struct device_node *node = NULL;
121 	struct device_node *clocks_node;
122 	struct clk_fixed_factor *factor;
123 	struct clk_fixed_rate *fixed;
124 	struct clk_init_data init_data = { };
125 	int ret;
126 
127 	clocks_node = of_find_node_by_path("/clocks");
128 	if (clocks_node) {
129 		node = of_get_child_by_name(clocks_node, path);
130 		of_node_put(clocks_node);
131 	}
132 
133 	if (!node) {
134 		fixed = devm_kzalloc(dev, sizeof(*fixed), GFP_KERNEL);
135 		if (!fixed)
136 			return -EINVAL;
137 
138 		fixed->fixed_rate = rate;
139 		fixed->hw.init = &init_data;
140 
141 		init_data.name = path;
142 		init_data.ops = &clk_fixed_rate_ops;
143 
144 		ret = devm_clk_hw_register(dev, &fixed->hw);
145 		if (ret)
146 			return ret;
147 	}
148 	of_node_put(node);
149 
150 	if (add_factor) {
151 		factor = devm_kzalloc(dev, sizeof(*factor), GFP_KERNEL);
152 		if (!factor)
153 			return -EINVAL;
154 
155 		factor->mult = factor->div = 1;
156 		factor->hw.init = &init_data;
157 
158 		init_data.name = name;
159 		init_data.parent_names = &path;
160 		init_data.num_parents = 1;
161 		init_data.flags = 0;
162 		init_data.ops = &clk_fixed_factor_ops;
163 
164 		ret = devm_clk_hw_register(dev, &factor->hw);
165 		if (ret)
166 			return ret;
167 	}
168 
169 	return 0;
170 }
171 
172 int qcom_cc_register_board_clk(struct device *dev, const char *path,
173 			       const char *name, unsigned long rate)
174 {
175 	bool add_factor = true;
176 
177 	/*
178 	 * TODO: The RPM clock driver currently does not support the xo clock.
179 	 * When xo is added to the RPM clock driver, we should change this
180 	 * function to skip registration of xo factor clocks.
181 	 */
182 
183 	return _qcom_cc_register_board_clk(dev, path, name, rate, add_factor);
184 }
185 EXPORT_SYMBOL_GPL(qcom_cc_register_board_clk);
186 
187 int qcom_cc_register_sleep_clk(struct device *dev)
188 {
189 	return _qcom_cc_register_board_clk(dev, "sleep_clk", "sleep_clk_src",
190 					   32768, true);
191 }
192 EXPORT_SYMBOL_GPL(qcom_cc_register_sleep_clk);
193 
194 /* Drop 'protected-clocks' from the list of clocks to register */
195 static void qcom_cc_drop_protected(struct device *dev, struct qcom_cc *cc)
196 {
197 	struct device_node *np = dev->of_node;
198 	struct property *prop;
199 	const __be32 *p;
200 	u32 i;
201 
202 	of_property_for_each_u32(np, "protected-clocks", prop, p, i) {
203 		if (i >= cc->num_rclks)
204 			continue;
205 
206 		cc->rclks[i] = NULL;
207 	}
208 }
209 
210 static struct clk_hw *qcom_cc_clk_hw_get(struct of_phandle_args *clkspec,
211 					 void *data)
212 {
213 	struct qcom_cc *cc = data;
214 	unsigned int idx = clkspec->args[0];
215 
216 	if (idx >= cc->num_rclks) {
217 		pr_err("%s: invalid index %u\n", __func__, idx);
218 		return ERR_PTR(-EINVAL);
219 	}
220 
221 	return cc->rclks[idx] ? &cc->rclks[idx]->hw : ERR_PTR(-ENOENT);
222 }
223 
224 int qcom_cc_really_probe(struct platform_device *pdev,
225 			 const struct qcom_cc_desc *desc, struct regmap *regmap)
226 {
227 	int i, ret;
228 	struct device *dev = &pdev->dev;
229 	struct qcom_reset_controller *reset;
230 	struct qcom_cc *cc;
231 	struct gdsc_desc *scd;
232 	size_t num_clks = desc->num_clks;
233 	struct clk_regmap **rclks = desc->clks;
234 
235 	cc = devm_kzalloc(dev, sizeof(*cc), GFP_KERNEL);
236 	if (!cc)
237 		return -ENOMEM;
238 
239 	reset = &cc->reset;
240 	reset->rcdev.of_node = dev->of_node;
241 	reset->rcdev.ops = &qcom_reset_ops;
242 	reset->rcdev.owner = dev->driver->owner;
243 	reset->rcdev.nr_resets = desc->num_resets;
244 	reset->regmap = regmap;
245 	reset->reset_map = desc->resets;
246 
247 	ret = devm_reset_controller_register(dev, &reset->rcdev);
248 	if (ret)
249 		return ret;
250 
251 	if (desc->gdscs && desc->num_gdscs) {
252 		scd = devm_kzalloc(dev, sizeof(*scd), GFP_KERNEL);
253 		if (!scd)
254 			return -ENOMEM;
255 		scd->dev = dev;
256 		scd->scs = desc->gdscs;
257 		scd->num = desc->num_gdscs;
258 		ret = gdsc_register(scd, &reset->rcdev, regmap);
259 		if (ret)
260 			return ret;
261 		ret = devm_add_action_or_reset(dev, qcom_cc_gdsc_unregister,
262 					       scd);
263 		if (ret)
264 			return ret;
265 	}
266 
267 	cc->rclks = rclks;
268 	cc->num_rclks = num_clks;
269 
270 	qcom_cc_drop_protected(dev, cc);
271 
272 	for (i = 0; i < num_clks; i++) {
273 		if (!rclks[i])
274 			continue;
275 
276 		ret = devm_clk_register_regmap(dev, rclks[i]);
277 		if (ret)
278 			return ret;
279 	}
280 
281 	ret = devm_of_clk_add_hw_provider(dev, qcom_cc_clk_hw_get, cc);
282 	if (ret)
283 		return ret;
284 
285 	return 0;
286 }
287 EXPORT_SYMBOL_GPL(qcom_cc_really_probe);
288 
289 int qcom_cc_probe(struct platform_device *pdev, const struct qcom_cc_desc *desc)
290 {
291 	struct regmap *regmap;
292 
293 	regmap = qcom_cc_map(pdev, desc);
294 	if (IS_ERR(regmap))
295 		return PTR_ERR(regmap);
296 
297 	return qcom_cc_really_probe(pdev, desc, regmap);
298 }
299 EXPORT_SYMBOL_GPL(qcom_cc_probe);
300 
301 MODULE_LICENSE("GPL v2");
302