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11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/clk.h>
14#include <linux/cpufreq.h>
15#include <linux/errno.h>
16#include <sysdev/fsl_soc.h>
17#include <linux/init.h>
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/mutex.h>
21#include <linux/of.h>
22#include <linux/slab.h>
23#include <linux/smp.h>
24
25
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27
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29
30
31struct cpu_data {
32 struct clk *clk;
33 struct device_node *parent;
34 struct cpufreq_frequency_table *table;
35};
36
37
38
39
40
41
42struct soc_data {
43 u32 freq_mask[4];
44 u32 flag;
45};
46
47#define FREQ_MASK 1
48
49static const struct soc_data sdata[] = {
50 {
51 .freq_mask = {0x8, 0x8, 0x2, 0x2},
52 .flag = FREQ_MASK,
53 },
54 {
55 .freq_mask = {0x8, 0x2},
56 .flag = FREQ_MASK,
57 },
58 {
59 .freq_mask = {0},
60 .flag = 0,
61 },
62};
63
64
65
66
67
68
69static u32 min_cpufreq;
70static const u32 *fmask;
71
72
73static DEFINE_MUTEX(cpufreq_lock);
74static DEFINE_PER_CPU(struct cpu_data *, cpu_data);
75
76
77static DEFINE_PER_CPU(cpumask_var_t, cpu_mask);
78
79#ifndef CONFIG_SMP
80static inline const struct cpumask *cpu_core_mask(int cpu)
81{
82 return cpumask_of(0);
83}
84#endif
85
86static unsigned int corenet_cpufreq_get_speed(unsigned int cpu)
87{
88 struct cpu_data *data = per_cpu(cpu_data, cpu);
89
90 return clk_get_rate(data->clk) / 1000;
91}
92
93
94static void freq_table_redup(struct cpufreq_frequency_table *freq_table,
95 int count)
96{
97 int i, j;
98
99 for (i = 1; i < count; i++) {
100 for (j = 0; j < i; j++) {
101 if (freq_table[j].frequency == CPUFREQ_ENTRY_INVALID ||
102 freq_table[j].frequency !=
103 freq_table[i].frequency)
104 continue;
105
106 freq_table[i].frequency = CPUFREQ_ENTRY_INVALID;
107 break;
108 }
109 }
110}
111
112
113static void freq_table_sort(struct cpufreq_frequency_table *freq_table,
114 int count)
115{
116 int i, j, ind;
117 unsigned int freq, max_freq;
118 struct cpufreq_frequency_table table;
119 for (i = 0; i < count - 1; i++) {
120 max_freq = freq_table[i].frequency;
121 ind = i;
122 for (j = i + 1; j < count; j++) {
123 freq = freq_table[j].frequency;
124 if (freq == CPUFREQ_ENTRY_INVALID ||
125 freq <= max_freq)
126 continue;
127 ind = j;
128 max_freq = freq;
129 }
130
131 if (ind != i) {
132
133 table.driver_data = freq_table[i].driver_data;
134 table.frequency = freq_table[i].frequency;
135 freq_table[i].driver_data = freq_table[ind].driver_data;
136 freq_table[i].frequency = freq_table[ind].frequency;
137 freq_table[ind].driver_data = table.driver_data;
138 freq_table[ind].frequency = table.frequency;
139 }
140 }
141}
142
143static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy)
144{
145 struct device_node *np;
146 int i, count, ret;
147 u32 freq, mask;
148 struct clk *clk;
149 struct cpufreq_frequency_table *table;
150 struct cpu_data *data;
151 unsigned int cpu = policy->cpu;
152
153 np = of_get_cpu_node(cpu, NULL);
154 if (!np)
155 return -ENODEV;
156
157 data = kzalloc(sizeof(*data), GFP_KERNEL);
158 if (!data) {
159 pr_err("%s: no memory\n", __func__);
160 goto err_np;
161 }
162
163 data->clk = of_clk_get(np, 0);
164 if (IS_ERR(data->clk)) {
165 pr_err("%s: no clock information\n", __func__);
166 goto err_nomem2;
167 }
168
169 data->parent = of_parse_phandle(np, "clocks", 0);
170 if (!data->parent) {
171 pr_err("%s: could not get clock information\n", __func__);
172 goto err_nomem2;
173 }
174
175 count = of_property_count_strings(data->parent, "clock-names");
176 table = kcalloc(count + 1, sizeof(*table), GFP_KERNEL);
177 if (!table) {
178 pr_err("%s: no memory\n", __func__);
179 goto err_node;
180 }
181
182 if (fmask)
183 mask = fmask[get_hard_smp_processor_id(cpu)];
184 else
185 mask = 0x0;
186
187 for (i = 0; i < count; i++) {
188 clk = of_clk_get(data->parent, i);
189 freq = clk_get_rate(clk);
190
191
192
193
194 if (freq < min_cpufreq || (mask & (1 << i)))
195 table[i].frequency = CPUFREQ_ENTRY_INVALID;
196 else
197 table[i].frequency = freq / 1000;
198 table[i].driver_data = i;
199 }
200 freq_table_redup(table, count);
201 freq_table_sort(table, count);
202 table[i].frequency = CPUFREQ_TABLE_END;
203
204
205 ret = cpufreq_frequency_table_cpuinfo(policy, table);
206 if (ret) {
207 pr_err("invalid frequency table: %d\n", ret);
208 goto err_nomem1;
209 }
210
211 data->table = table;
212 per_cpu(cpu_data, cpu) = data;
213
214
215 cpumask_copy(policy->cpus, per_cpu(cpu_mask, cpu));
216 for_each_cpu(i, per_cpu(cpu_mask, cpu))
217 per_cpu(cpu_data, i) = data;
218
219 policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
220 policy->cur = corenet_cpufreq_get_speed(policy->cpu);
221
222 cpufreq_frequency_table_get_attr(table, cpu);
223 of_node_put(np);
224
225 return 0;
226
227err_nomem1:
228 kfree(table);
229err_node:
230 of_node_put(data->parent);
231err_nomem2:
232 per_cpu(cpu_data, cpu) = NULL;
233 kfree(data);
234err_np:
235 of_node_put(np);
236
237 return -ENODEV;
238}
239
240static int __exit corenet_cpufreq_cpu_exit(struct cpufreq_policy *policy)
241{
242 struct cpu_data *data = per_cpu(cpu_data, policy->cpu);
243 unsigned int cpu;
244
245 cpufreq_frequency_table_put_attr(policy->cpu);
246 of_node_put(data->parent);
247 kfree(data->table);
248 kfree(data);
249
250 for_each_cpu(cpu, per_cpu(cpu_mask, policy->cpu))
251 per_cpu(cpu_data, cpu) = NULL;
252
253 return 0;
254}
255
256static int corenet_cpufreq_verify(struct cpufreq_policy *policy)
257{
258 struct cpufreq_frequency_table *table =
259 per_cpu(cpu_data, policy->cpu)->table;
260
261 return cpufreq_frequency_table_verify(policy, table);
262}
263
264static int corenet_cpufreq_target(struct cpufreq_policy *policy,
265 unsigned int target_freq, unsigned int relation)
266{
267 struct cpufreq_freqs freqs;
268 unsigned int new;
269 struct clk *parent;
270 int ret;
271 struct cpu_data *data = per_cpu(cpu_data, policy->cpu);
272
273 cpufreq_frequency_table_target(policy, data->table,
274 target_freq, relation, &new);
275
276 if (policy->cur == data->table[new].frequency)
277 return 0;
278
279 freqs.old = policy->cur;
280 freqs.new = data->table[new].frequency;
281
282 mutex_lock(&cpufreq_lock);
283 cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
284
285 parent = of_clk_get(data->parent, data->table[new].driver_data);
286 ret = clk_set_parent(data->clk, parent);
287 if (ret)
288 freqs.new = freqs.old;
289
290 cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
291 mutex_unlock(&cpufreq_lock);
292
293 return ret;
294}
295
296static struct freq_attr *corenet_cpufreq_attr[] = {
297 &cpufreq_freq_attr_scaling_available_freqs,
298 NULL,
299};
300
301static struct cpufreq_driver ppc_corenet_cpufreq_driver = {
302 .name = "ppc_cpufreq",
303 .owner = THIS_MODULE,
304 .flags = CPUFREQ_CONST_LOOPS,
305 .init = corenet_cpufreq_cpu_init,
306 .exit = __exit_p(corenet_cpufreq_cpu_exit),
307 .verify = corenet_cpufreq_verify,
308 .target = corenet_cpufreq_target,
309 .get = corenet_cpufreq_get_speed,
310 .attr = corenet_cpufreq_attr,
311};
312
313static const struct of_device_id node_matches[] __initdata = {
314 { .compatible = "fsl,p2041-clockgen", .data = &sdata[0], },
315 { .compatible = "fsl,p3041-clockgen", .data = &sdata[0], },
316 { .compatible = "fsl,p5020-clockgen", .data = &sdata[1], },
317 { .compatible = "fsl,p4080-clockgen", .data = &sdata[2], },
318 { .compatible = "fsl,p5040-clockgen", .data = &sdata[2], },
319 { .compatible = "fsl,qoriq-clockgen-2.0", },
320 {}
321};
322
323static int __init ppc_corenet_cpufreq_init(void)
324{
325 int ret;
326 struct device_node *np;
327 const struct of_device_id *match;
328 const struct soc_data *data;
329 unsigned int cpu;
330
331 np = of_find_matching_node(NULL, node_matches);
332 if (!np)
333 return -ENODEV;
334
335 for_each_possible_cpu(cpu) {
336 if (!alloc_cpumask_var(&per_cpu(cpu_mask, cpu), GFP_KERNEL))
337 goto err_mask;
338 cpumask_copy(per_cpu(cpu_mask, cpu), cpu_core_mask(cpu));
339 }
340
341 match = of_match_node(node_matches, np);
342 data = match->data;
343 if (data) {
344 if (data->flag)
345 fmask = data->freq_mask;
346 min_cpufreq = fsl_get_sys_freq();
347 } else {
348 min_cpufreq = fsl_get_sys_freq() / 2;
349 }
350
351 of_node_put(np);
352
353 ret = cpufreq_register_driver(&ppc_corenet_cpufreq_driver);
354 if (!ret)
355 pr_info("Freescale PowerPC corenet CPU frequency scaling driver\n");
356
357 return ret;
358
359err_mask:
360 for_each_possible_cpu(cpu)
361 free_cpumask_var(per_cpu(cpu_mask, cpu));
362
363 return -ENOMEM;
364}
365module_init(ppc_corenet_cpufreq_init);
366
367static void __exit ppc_corenet_cpufreq_exit(void)
368{
369 unsigned int cpu;
370
371 for_each_possible_cpu(cpu)
372 free_cpumask_var(per_cpu(cpu_mask, cpu));
373
374 cpufreq_unregister_driver(&ppc_corenet_cpufreq_driver);
375}
376module_exit(ppc_corenet_cpufreq_exit);
377
378MODULE_LICENSE("GPL");
379MODULE_AUTHOR("Tang Yuantian <Yuantian.Tang@freescale.com>");
380MODULE_DESCRIPTION("cpufreq driver for Freescale e500mc series SoCs");
381
