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 PowerPC corenet SoCs.
9 */
10 #include <linux/clk-provider.h>
11 #include <linux/io.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/of_address.h>
15 #include <linux/of_platform.h>
16 #include <linux/of.h>
17 #include <linux/slab.h>
18
19 struct cmux_clk {
20 struct clk_hw hw;
21 void __iomem *reg;
22 u32 flags;
23 };
24
25 #define PLL_KILL BIT(31)
26 #define CLKSEL_SHIFT 27
27 #define CLKSEL_ADJUST BIT(0)
28 #define to_cmux_clk(p) container_of(p, struct cmux_clk, hw)
29
30 static unsigned int clocks_per_pll;
31
cmux_set_parent(struct clk_hw * hw,u8 idx)32 static int cmux_set_parent(struct clk_hw *hw, u8 idx)
33 {
34 struct cmux_clk *clk = to_cmux_clk(hw);
35 u32 clksel;
36
37 clksel = ((idx / clocks_per_pll) << 2) + idx % clocks_per_pll;
38 if (clk->flags & CLKSEL_ADJUST)
39 clksel += 8;
40 clksel = (clksel & 0xf) << CLKSEL_SHIFT;
41 iowrite32be(clksel, clk->reg);
42
43 return 0;
44 }
45
cmux_get_parent(struct clk_hw * hw)46 static u8 cmux_get_parent(struct clk_hw *hw)
47 {
48 struct cmux_clk *clk = to_cmux_clk(hw);
49 u32 clksel;
50
51 clksel = ioread32be(clk->reg);
52 clksel = (clksel >> CLKSEL_SHIFT) & 0xf;
53 if (clk->flags & CLKSEL_ADJUST)
54 clksel -= 8;
55 clksel = (clksel >> 2) * clocks_per_pll + clksel % 4;
56
57 return clksel;
58 }
59
60 const struct clk_ops cmux_ops = {
61 .get_parent = cmux_get_parent,
62 .set_parent = cmux_set_parent,
63 };
64
core_mux_init(struct device_node * np)65 static void __init core_mux_init(struct device_node *np)
66 {
67 struct clk *clk;
68 struct clk_init_data init;
69 struct cmux_clk *cmux_clk;
70 struct device_node *node;
71 int rc, count, i;
72 u32 offset;
73 const char *clk_name;
74 const char **parent_names;
75
76 rc = of_property_read_u32(np, "reg", &offset);
77 if (rc) {
78 pr_err("%s: could not get reg property\n", np->name);
79 return;
80 }
81
82 /* get the input clock source count */
83 count = of_property_count_strings(np, "clock-names");
84 if (count < 0) {
85 pr_err("%s: get clock count error\n", np->name);
86 return;
87 }
88 parent_names = kzalloc((sizeof(char *) * count), GFP_KERNEL);
89 if (!parent_names) {
90 pr_err("%s: could not allocate parent_names\n", __func__);
91 return;
92 }
93
94 for (i = 0; i < count; i++)
95 parent_names[i] = of_clk_get_parent_name(np, i);
96
97 cmux_clk = kzalloc(sizeof(struct cmux_clk), GFP_KERNEL);
98 if (!cmux_clk) {
99 pr_err("%s: could not allocate cmux_clk\n", __func__);
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 node = of_find_compatible_node(NULL, NULL, "fsl,p4080-clockgen");
109 if (node && (offset >= 0x80))
110 cmux_clk->flags = CLKSEL_ADJUST;
111
112 rc = of_property_read_string_index(np, "clock-output-names",
113 0, &clk_name);
114 if (rc) {
115 pr_err("%s: read clock names error\n", np->name);
116 goto err_clk;
117 }
118
119 init.name = clk_name;
120 init.ops = &cmux_ops;
121 init.parent_names = parent_names;
122 init.num_parents = count;
123 init.flags = 0;
124 cmux_clk->hw.init = &init;
125
126 clk = clk_register(NULL, &cmux_clk->hw);
127 if (IS_ERR(clk)) {
128 pr_err("%s: could not register clock\n", clk_name);
129 goto err_clk;
130 }
131
132 rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
133 if (rc) {
134 pr_err("Could not register clock provider for node:%s\n",
135 np->name);
136 goto err_clk;
137 }
138 goto err_name;
139
140 err_clk:
141 kfree(cmux_clk);
142 err_name:
143 /* free *_names because they are reallocated when registered */
144 kfree(parent_names);
145 }
146
core_pll_init(struct device_node * np)147 static void __init core_pll_init(struct device_node *np)
148 {
149 u32 mult;
150 int i, rc, count;
151 const char *clk_name, *parent_name;
152 struct clk_onecell_data *onecell_data;
153 struct clk **subclks;
154 void __iomem *base;
155
156 base = of_iomap(np, 0);
157 if (!base) {
158 pr_err("clk-ppc: iomap error\n");
159 return;
160 }
161
162 /* get the multiple of PLL */
163 mult = ioread32be(base);
164
165 /* check if this PLL is disabled */
166 if (mult & PLL_KILL) {
167 pr_debug("PLL:%s is disabled\n", np->name);
168 goto err_map;
169 }
170 mult = (mult >> 1) & 0x3f;
171
172 parent_name = of_clk_get_parent_name(np, 0);
173 if (!parent_name) {
174 pr_err("PLL: %s must have a parent\n", np->name);
175 goto err_map;
176 }
177
178 count = of_property_count_strings(np, "clock-output-names");
179 if (count < 0 || count > 4) {
180 pr_err("%s: clock is not supported\n", np->name);
181 goto err_map;
182 }
183
184 /* output clock number per PLL */
185 clocks_per_pll = count;
186
187 subclks = kzalloc(sizeof(struct clk *) * count, GFP_KERNEL);
188 if (!subclks) {
189 pr_err("%s: could not allocate subclks\n", __func__);
190 goto err_map;
191 }
192
193 onecell_data = kzalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
194 if (!onecell_data) {
195 pr_err("%s: could not allocate onecell_data\n", __func__);
196 goto err_clks;
197 }
198
199 for (i = 0; i < count; i++) {
200 rc = of_property_read_string_index(np, "clock-output-names",
201 i, &clk_name);
202 if (rc) {
203 pr_err("%s: could not get clock names\n", np->name);
204 goto err_cell;
205 }
206
207 /*
208 * when count == 4, there are 4 output clocks:
209 * /1, /2, /3, /4 respectively
210 * when count < 4, there are at least 2 output clocks:
211 * /1, /2, (/4, if count == 3) respectively.
212 */
213 if (count == 4)
214 subclks[i] = clk_register_fixed_factor(NULL, clk_name,
215 parent_name, 0, mult, 1 + i);
216 else
217
218 subclks[i] = clk_register_fixed_factor(NULL, clk_name,
219 parent_name, 0, mult, 1 << i);
220
221 if (IS_ERR(subclks[i])) {
222 pr_err("%s: could not register clock\n", clk_name);
223 goto err_cell;
224 }
225 }
226
227 onecell_data->clks = subclks;
228 onecell_data->clk_num = count;
229
230 rc = of_clk_add_provider(np, of_clk_src_onecell_get, onecell_data);
231 if (rc) {
232 pr_err("Could not register clk provider for node:%s\n",
233 np->name);
234 goto err_cell;
235 }
236
237 iounmap(base);
238 return;
239 err_cell:
240 kfree(onecell_data);
241 err_clks:
242 kfree(subclks);
243 err_map:
244 iounmap(base);
245 }
246
sysclk_init(struct device_node * node)247 static void __init sysclk_init(struct device_node *node)
248 {
249 struct clk *clk;
250 const char *clk_name = node->name;
251 struct device_node *np = of_get_parent(node);
252 u32 rate;
253
254 if (!np) {
255 pr_err("ppc-clk: could not get parent node\n");
256 return;
257 }
258
259 if (of_property_read_u32(np, "clock-frequency", &rate)) {
260 of_node_put(node);
261 return;
262 }
263
264 of_property_read_string(np, "clock-output-names", &clk_name);
265
266 clk = clk_register_fixed_rate(NULL, clk_name, NULL, CLK_IS_ROOT, rate);
267 if (!IS_ERR(clk))
268 of_clk_add_provider(np, of_clk_src_simple_get, clk);
269 }
270
271 static const struct of_device_id clk_match[] __initconst = {
272 { .compatible = "fsl,qoriq-sysclk-1.0", .data = sysclk_init, },
273 { .compatible = "fsl,qoriq-sysclk-2.0", .data = sysclk_init, },
274 { .compatible = "fsl,qoriq-core-pll-1.0", .data = core_pll_init, },
275 { .compatible = "fsl,qoriq-core-pll-2.0", .data = core_pll_init, },
276 { .compatible = "fsl,qoriq-core-mux-1.0", .data = core_mux_init, },
277 { .compatible = "fsl,qoriq-core-mux-2.0", .data = core_mux_init, },
278 {}
279 };
280
ppc_corenet_clk_probe(struct platform_device * pdev)281 static int __init ppc_corenet_clk_probe(struct platform_device *pdev)
282 {
283 of_clk_init(clk_match);
284
285 return 0;
286 }
287
288 static const struct of_device_id ppc_clk_ids[] __initconst = {
289 { .compatible = "fsl,qoriq-clockgen-1.0", },
290 { .compatible = "fsl,qoriq-clockgen-2.0", },
291 {}
292 };
293
294 static struct platform_driver ppc_corenet_clk_driver = {
295 .driver = {
296 .name = "ppc_corenet_clock",
297 .owner = THIS_MODULE,
298 .of_match_table = ppc_clk_ids,
299 },
300 .probe = ppc_corenet_clk_probe,
301 };
302
ppc_corenet_clk_init(void)303 static int __init ppc_corenet_clk_init(void)
304 {
305 return platform_driver_register(&ppc_corenet_clk_driver);
306 }
307 subsys_initcall(ppc_corenet_clk_init);
308