1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23#include <linux/cpufreq.h>
24#include <linux/module.h>
25#include <linux/of_platform.h>
26
27#include <asm/machdep.h>
28#include <asm/prom.h>
29#include <asm/cell-regs.h>
30
31#include "ppc_cbe_cpufreq.h"
32
33static DEFINE_MUTEX(cbe_switch_mutex);
34
35
36
37static struct cpufreq_frequency_table cbe_freqs[] = {
38 {1, 0},
39 {2, 0},
40 {3, 0},
41 {4, 0},
42 {5, 0},
43 {6, 0},
44 {8, 0},
45 {10, 0},
46 {0, CPUFREQ_TABLE_END},
47};
48
49
50
51
52
53static int set_pmode(unsigned int cpu, unsigned int slow_mode)
54{
55 int rc;
56
57 if (cbe_cpufreq_has_pmi)
58 rc = cbe_cpufreq_set_pmode_pmi(cpu, slow_mode);
59 else
60 rc = cbe_cpufreq_set_pmode(cpu, slow_mode);
61
62 pr_debug("register contains slow mode %d\n", cbe_cpufreq_get_pmode(cpu));
63
64 return rc;
65}
66
67
68
69
70
71static int cbe_cpufreq_cpu_init(struct cpufreq_policy *policy)
72{
73 const u32 *max_freqp;
74 u32 max_freq;
75 int i, cur_pmode;
76 struct device_node *cpu;
77
78 cpu = of_get_cpu_node(policy->cpu, NULL);
79
80 if (!cpu)
81 return -ENODEV;
82
83 pr_debug("init cpufreq on CPU %d\n", policy->cpu);
84
85
86
87
88 if (!cbe_get_cpu_pmd_regs(policy->cpu) ||
89 !cbe_get_cpu_mic_tm_regs(policy->cpu)) {
90 pr_info("invalid CBE regs pointers for cpufreq\n");
91 return -EINVAL;
92 }
93
94 max_freqp = of_get_property(cpu, "clock-frequency", NULL);
95
96 of_node_put(cpu);
97
98 if (!max_freqp)
99 return -EINVAL;
100
101
102 max_freq = *max_freqp / 1000;
103
104 pr_debug("max clock-frequency is at %u kHz\n", max_freq);
105 pr_debug("initializing frequency table\n");
106
107
108 for (i=0; cbe_freqs[i].frequency!=CPUFREQ_TABLE_END; i++) {
109 cbe_freqs[i].frequency = max_freq / cbe_freqs[i].driver_data;
110 pr_debug("%d: %d\n", i, cbe_freqs[i].frequency);
111 }
112
113
114
115 policy->cpuinfo.transition_latency = 25000;
116
117 cur_pmode = cbe_cpufreq_get_pmode(policy->cpu);
118 pr_debug("current pmode is at %d\n",cur_pmode);
119
120 policy->cur = cbe_freqs[cur_pmode].frequency;
121
122#ifdef CONFIG_SMP
123 cpumask_copy(policy->cpus, cpu_sibling_mask(policy->cpu));
124#endif
125
126 cpufreq_frequency_table_get_attr(cbe_freqs, policy->cpu);
127
128
129
130 return cpufreq_frequency_table_cpuinfo(policy, cbe_freqs);
131}
132
133static int cbe_cpufreq_cpu_exit(struct cpufreq_policy *policy)
134{
135 cpufreq_frequency_table_put_attr(policy->cpu);
136 return 0;
137}
138
139static int cbe_cpufreq_verify(struct cpufreq_policy *policy)
140{
141 return cpufreq_frequency_table_verify(policy, cbe_freqs);
142}
143
144static int cbe_cpufreq_target(struct cpufreq_policy *policy,
145 unsigned int target_freq,
146 unsigned int relation)
147{
148 int rc;
149 struct cpufreq_freqs freqs;
150 unsigned int cbe_pmode_new;
151
152 cpufreq_frequency_table_target(policy,
153 cbe_freqs,
154 target_freq,
155 relation,
156 &cbe_pmode_new);
157
158 freqs.old = policy->cur;
159 freqs.new = cbe_freqs[cbe_pmode_new].frequency;
160
161 mutex_lock(&cbe_switch_mutex);
162 cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
163
164 pr_debug("setting frequency for cpu %d to %d kHz, " \
165 "1/%d of max frequency\n",
166 policy->cpu,
167 cbe_freqs[cbe_pmode_new].frequency,
168 cbe_freqs[cbe_pmode_new].driver_data);
169
170 rc = set_pmode(policy->cpu, cbe_pmode_new);
171
172 cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
173 mutex_unlock(&cbe_switch_mutex);
174
175 return rc;
176}
177
178static struct cpufreq_driver cbe_cpufreq_driver = {
179 .verify = cbe_cpufreq_verify,
180 .target = cbe_cpufreq_target,
181 .init = cbe_cpufreq_cpu_init,
182 .exit = cbe_cpufreq_cpu_exit,
183 .name = "cbe-cpufreq",
184 .owner = THIS_MODULE,
185 .flags = CPUFREQ_CONST_LOOPS,
186};
187
188
189
190
191
192static int __init cbe_cpufreq_init(void)
193{
194 if (!machine_is(cell))
195 return -ENODEV;
196
197 return cpufreq_register_driver(&cbe_cpufreq_driver);
198}
199
200static void __exit cbe_cpufreq_exit(void)
201{
202 cpufreq_unregister_driver(&cbe_cpufreq_driver);
203}
204
205module_init(cbe_cpufreq_init);
206module_exit(cbe_cpufreq_exit);
207
208MODULE_LICENSE("GPL");
209MODULE_AUTHOR("Christian Krafft <krafft@de.ibm.com>");
210