xref: /openbmc/linux/drivers/clk/clk-qoriq.c (revision a2cce7a9)
1 /*
2  * Copyright 2013 Freescale Semiconductor, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * clock driver for Freescale QorIQ SoCs.
9  */
10 
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #include <linux/clk-provider.h>
14 #include <linux/io.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/of_address.h>
18 #include <linux/of_platform.h>
19 #include <linux/of.h>
20 #include <linux/slab.h>
21 
22 struct cmux_clk {
23 	struct clk_hw hw;
24 	void __iomem *reg;
25 	unsigned int clk_per_pll;
26 	u32 flags;
27 };
28 
29 #define PLL_KILL			BIT(31)
30 #define	CLKSEL_SHIFT		27
31 #define CLKSEL_ADJUST		BIT(0)
32 #define to_cmux_clk(p)		container_of(p, struct cmux_clk, hw)
33 
34 static int cmux_set_parent(struct clk_hw *hw, u8 idx)
35 {
36 	struct cmux_clk *clk = to_cmux_clk(hw);
37 	u32 clksel;
38 
39 	clksel = ((idx / clk->clk_per_pll) << 2) + idx % clk->clk_per_pll;
40 	if (clk->flags & CLKSEL_ADJUST)
41 		clksel += 8;
42 	clksel = (clksel & 0xf) << CLKSEL_SHIFT;
43 	iowrite32be(clksel, clk->reg);
44 
45 	return 0;
46 }
47 
48 static u8 cmux_get_parent(struct clk_hw *hw)
49 {
50 	struct cmux_clk *clk = to_cmux_clk(hw);
51 	u32 clksel;
52 
53 	clksel = ioread32be(clk->reg);
54 	clksel = (clksel >> CLKSEL_SHIFT) & 0xf;
55 	if (clk->flags & CLKSEL_ADJUST)
56 		clksel -= 8;
57 	clksel = (clksel >> 2) * clk->clk_per_pll + clksel % 4;
58 
59 	return clksel;
60 }
61 
62 static const struct clk_ops cmux_ops = {
63 	.get_parent = cmux_get_parent,
64 	.set_parent = cmux_set_parent,
65 };
66 
67 static void __init core_mux_init(struct device_node *np)
68 {
69 	struct clk *clk;
70 	struct clk_init_data init;
71 	struct cmux_clk *cmux_clk;
72 	struct device_node *node;
73 	int rc, count, i;
74 	u32	offset;
75 	const char *clk_name;
76 	const char **parent_names;
77 	struct of_phandle_args clkspec;
78 
79 	rc = of_property_read_u32(np, "reg", &offset);
80 	if (rc) {
81 		pr_err("%s: could not get reg property\n", np->name);
82 		return;
83 	}
84 
85 	/* get the input clock source count */
86 	count = of_property_count_strings(np, "clock-names");
87 	if (count < 0) {
88 		pr_err("%s: get clock count error\n", np->name);
89 		return;
90 	}
91 	parent_names = kcalloc(count, sizeof(char *), GFP_KERNEL);
92 	if (!parent_names)
93 		return;
94 
95 	for (i = 0; i < count; i++)
96 		parent_names[i] = of_clk_get_parent_name(np, i);
97 
98 	cmux_clk = kzalloc(sizeof(*cmux_clk), GFP_KERNEL);
99 	if (!cmux_clk)
100 		goto err_name;
101 
102 	cmux_clk->reg = of_iomap(np, 0);
103 	if (!cmux_clk->reg) {
104 		pr_err("%s: could not map register\n", __func__);
105 		goto err_clk;
106 	}
107 
108 	rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", 0,
109 					&clkspec);
110 	if (rc) {
111 		pr_err("%s: parse clock node error\n", __func__);
112 		goto err_clk;
113 	}
114 
115 	cmux_clk->clk_per_pll = of_property_count_strings(clkspec.np,
116 			"clock-output-names");
117 	of_node_put(clkspec.np);
118 
119 	node = of_find_compatible_node(NULL, NULL, "fsl,p4080-clockgen");
120 	if (node && (offset >= 0x80))
121 		cmux_clk->flags = CLKSEL_ADJUST;
122 
123 	rc = of_property_read_string_index(np, "clock-output-names",
124 					   0, &clk_name);
125 	if (rc) {
126 		pr_err("%s: read clock names error\n", np->name);
127 		goto err_clk;
128 	}
129 
130 	init.name = clk_name;
131 	init.ops = &cmux_ops;
132 	init.parent_names = parent_names;
133 	init.num_parents = count;
134 	init.flags = 0;
135 	cmux_clk->hw.init = &init;
136 
137 	clk = clk_register(NULL, &cmux_clk->hw);
138 	if (IS_ERR(clk)) {
139 		pr_err("%s: could not register clock\n", clk_name);
140 		goto err_clk;
141 	}
142 
143 	rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
144 	if (rc) {
145 		pr_err("Could not register clock provider for node:%s\n",
146 		       np->name);
147 		goto err_clk;
148 	}
149 	goto err_name;
150 
151 err_clk:
152 	kfree(cmux_clk);
153 err_name:
154 	/* free *_names because they are reallocated when registered */
155 	kfree(parent_names);
156 }
157 
158 static void __init core_pll_init(struct device_node *np)
159 {
160 	u32 mult;
161 	int i, rc, count;
162 	const char *clk_name, *parent_name;
163 	struct clk_onecell_data *onecell_data;
164 	struct clk      **subclks;
165 	void __iomem *base;
166 
167 	base = of_iomap(np, 0);
168 	if (!base) {
169 		pr_err("iomap error\n");
170 		return;
171 	}
172 
173 	/* get the multiple of PLL */
174 	mult = ioread32be(base);
175 
176 	/* check if this PLL is disabled */
177 	if (mult & PLL_KILL) {
178 		pr_debug("PLL:%s is disabled\n", np->name);
179 		goto err_map;
180 	}
181 	mult = (mult >> 1) & 0x3f;
182 
183 	parent_name = of_clk_get_parent_name(np, 0);
184 	if (!parent_name) {
185 		pr_err("PLL: %s must have a parent\n", np->name);
186 		goto err_map;
187 	}
188 
189 	count = of_property_count_strings(np, "clock-output-names");
190 	if (count < 0 || count > 4) {
191 		pr_err("%s: clock is not supported\n", np->name);
192 		goto err_map;
193 	}
194 
195 	subclks = kcalloc(count, sizeof(struct clk *), GFP_KERNEL);
196 	if (!subclks)
197 		goto err_map;
198 
199 	onecell_data = kmalloc(sizeof(*onecell_data), GFP_KERNEL);
200 	if (!onecell_data)
201 		goto err_clks;
202 
203 	for (i = 0; i < count; i++) {
204 		rc = of_property_read_string_index(np, "clock-output-names",
205 						   i, &clk_name);
206 		if (rc) {
207 			pr_err("%s: could not get clock names\n", np->name);
208 			goto err_cell;
209 		}
210 
211 		/*
212 		 * when count == 4, there are 4 output clocks:
213 		 * /1, /2, /3, /4 respectively
214 		 * when count < 4, there are at least 2 output clocks:
215 		 * /1, /2, (/4, if count == 3) respectively.
216 		 */
217 		if (count == 4)
218 			subclks[i] = clk_register_fixed_factor(NULL, clk_name,
219 					parent_name, 0, mult, 1 + i);
220 		else
221 
222 			subclks[i] = clk_register_fixed_factor(NULL, clk_name,
223 					parent_name, 0, mult, 1 << i);
224 
225 		if (IS_ERR(subclks[i])) {
226 			pr_err("%s: could not register clock\n", clk_name);
227 			goto err_cell;
228 		}
229 	}
230 
231 	onecell_data->clks = subclks;
232 	onecell_data->clk_num = count;
233 
234 	rc = of_clk_add_provider(np, of_clk_src_onecell_get, onecell_data);
235 	if (rc) {
236 		pr_err("Could not register clk provider for node:%s\n",
237 		       np->name);
238 		goto err_cell;
239 	}
240 
241 	iounmap(base);
242 	return;
243 err_cell:
244 	kfree(onecell_data);
245 err_clks:
246 	kfree(subclks);
247 err_map:
248 	iounmap(base);
249 }
250 
251 static void __init sysclk_init(struct device_node *node)
252 {
253 	struct clk *clk;
254 	const char *clk_name = node->name;
255 	struct device_node *np = of_get_parent(node);
256 	u32 rate;
257 
258 	if (!np) {
259 		pr_err("could not get parent node\n");
260 		return;
261 	}
262 
263 	if (of_property_read_u32(np, "clock-frequency", &rate)) {
264 		of_node_put(node);
265 		return;
266 	}
267 
268 	of_property_read_string(np, "clock-output-names", &clk_name);
269 
270 	clk = clk_register_fixed_rate(NULL, clk_name, NULL, CLK_IS_ROOT, rate);
271 	if (!IS_ERR(clk))
272 		of_clk_add_provider(np, of_clk_src_simple_get, clk);
273 }
274 
275 static void __init pltfrm_pll_init(struct device_node *np)
276 {
277 	void __iomem *base;
278 	uint32_t mult;
279 	const char *parent_name, *clk_name;
280 	int i, _errno;
281 	struct clk_onecell_data *cod;
282 
283 	base = of_iomap(np, 0);
284 	if (!base) {
285 		pr_err("%s(): %s: of_iomap() failed\n", __func__, np->name);
286 		return;
287 	}
288 
289 	/* Get the multiple of PLL */
290 	mult = ioread32be(base);
291 
292 	iounmap(base);
293 
294 	/* Check if this PLL is disabled */
295 	if (mult & PLL_KILL) {
296 		pr_debug("%s(): %s: Disabled\n", __func__, np->name);
297 		return;
298 	}
299 	mult = (mult & GENMASK(6, 1)) >> 1;
300 
301 	parent_name = of_clk_get_parent_name(np, 0);
302 	if (!parent_name) {
303 		pr_err("%s(): %s: of_clk_get_parent_name() failed\n",
304 		       __func__, np->name);
305 		return;
306 	}
307 
308 	i = of_property_count_strings(np, "clock-output-names");
309 	if (i < 0) {
310 		pr_err("%s(): %s: of_property_count_strings(clock-output-names) = %d\n",
311 		       __func__, np->name, i);
312 		return;
313 	}
314 
315 	cod = kmalloc(sizeof(*cod) + i * sizeof(struct clk *), GFP_KERNEL);
316 	if (!cod)
317 		return;
318 	cod->clks = (struct clk **)(cod + 1);
319 	cod->clk_num = i;
320 
321 	for (i = 0; i < cod->clk_num; i++) {
322 		_errno = of_property_read_string_index(np, "clock-output-names",
323 						       i, &clk_name);
324 		if (_errno < 0) {
325 			pr_err("%s(): %s: of_property_read_string_index(clock-output-names) = %d\n",
326 			       __func__, np->name, _errno);
327 			goto return_clk_unregister;
328 		}
329 
330 		cod->clks[i] = clk_register_fixed_factor(NULL, clk_name,
331 					       parent_name, 0, mult, 1 + i);
332 		if (IS_ERR(cod->clks[i])) {
333 			pr_err("%s(): %s: clk_register_fixed_factor(%s) = %ld\n",
334 			       __func__, np->name,
335 			       clk_name, PTR_ERR(cod->clks[i]));
336 			goto return_clk_unregister;
337 		}
338 	}
339 
340 	_errno = of_clk_add_provider(np, of_clk_src_onecell_get, cod);
341 	if (_errno < 0) {
342 		pr_err("%s(): %s: of_clk_add_provider() = %d\n",
343 		       __func__, np->name, _errno);
344 		goto return_clk_unregister;
345 	}
346 
347 	return;
348 
349 return_clk_unregister:
350 	while (--i >= 0)
351 		clk_unregister(cod->clks[i]);
352 	kfree(cod);
353 }
354 
355 CLK_OF_DECLARE(qoriq_sysclk_1, "fsl,qoriq-sysclk-1.0", sysclk_init);
356 CLK_OF_DECLARE(qoriq_sysclk_2, "fsl,qoriq-sysclk-2.0", sysclk_init);
357 CLK_OF_DECLARE(qoriq_core_pll_1, "fsl,qoriq-core-pll-1.0", core_pll_init);
358 CLK_OF_DECLARE(qoriq_core_pll_2, "fsl,qoriq-core-pll-2.0", core_pll_init);
359 CLK_OF_DECLARE(qoriq_core_mux_1, "fsl,qoriq-core-mux-1.0", core_mux_init);
360 CLK_OF_DECLARE(qoriq_core_mux_2, "fsl,qoriq-core-mux-2.0", core_mux_init);
361 CLK_OF_DECLARE(qoriq_pltfrm_pll_1, "fsl,qoriq-platform-pll-1.0", pltfrm_pll_init);
362 CLK_OF_DECLARE(qoriq_pltfrm_pll_2, "fsl,qoriq-platform-pll-2.0", pltfrm_pll_init);
363