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-rw-r--r--arch/arm/mach-imx/cpufreq.c202
1 files changed, 0 insertions, 202 deletions
diff --git a/arch/arm/mach-imx/cpufreq.c b/arch/arm/mach-imx/cpufreq.c
deleted file mode 100644
index 387dc4cceca2..000000000000
--- a/arch/arm/mach-imx/cpufreq.c
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1/*
2 * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
3 */
4
5/*
6 * The code contained herein is licensed under the GNU General Public
7 * License. You may obtain a copy of the GNU General Public License
8 * Version 2 or later at the following locations:
9 *
10 * http://www.opensource.org/licenses/gpl-license.html
11 * http://www.gnu.org/copyleft/gpl.html
12 */
13
14/*
15 * A driver for the Freescale Semiconductor i.MXC CPUfreq module.
16 * The CPUFREQ driver is for controlling CPU frequency. It allows you to change
17 * the CPU clock speed on the fly.
18 */
19
20#include <linux/module.h>
21#include <linux/cpufreq.h>
22#include <linux/clk.h>
23#include <linux/err.h>
24#include <linux/slab.h>
25
26#include "hardware.h"
27
28#define CLK32_FREQ 32768
29#define NANOSECOND (1000 * 1000 * 1000)
30
31struct cpu_op *(*get_cpu_op)(int *op);
32
33static int cpu_freq_khz_min;
34static int cpu_freq_khz_max;
35
36static struct clk *cpu_clk;
37static struct cpufreq_frequency_table *imx_freq_table;
38
39static int cpu_op_nr;
40static struct cpu_op *cpu_op_tbl;
41
42static int set_cpu_freq(int freq)
43{
44 int ret = 0;
45 int org_cpu_rate;
46
47 org_cpu_rate = clk_get_rate(cpu_clk);
48 if (org_cpu_rate == freq)
49 return ret;
50
51 ret = clk_set_rate(cpu_clk, freq);
52 if (ret != 0) {
53 printk(KERN_DEBUG "cannot set CPU clock rate\n");
54 return ret;
55 }
56
57 return ret;
58}
59
60static int mxc_verify_speed(struct cpufreq_policy *policy)
61{
62 if (policy->cpu != 0)
63 return -EINVAL;
64
65 return cpufreq_frequency_table_verify(policy, imx_freq_table);
66}
67
68static unsigned int mxc_get_speed(unsigned int cpu)
69{
70 if (cpu)
71 return 0;
72
73 return clk_get_rate(cpu_clk) / 1000;
74}
75
76static int mxc_set_target(struct cpufreq_policy *policy,
77 unsigned int target_freq, unsigned int relation)
78{
79 struct cpufreq_freqs freqs;
80 int freq_Hz;
81 int ret = 0;
82 unsigned int index;
83
84 cpufreq_frequency_table_target(policy, imx_freq_table,
85 target_freq, relation, &index);
86 freq_Hz = imx_freq_table[index].frequency * 1000;
87
88 freqs.old = clk_get_rate(cpu_clk) / 1000;
89 freqs.new = freq_Hz / 1000;
90 freqs.flags = 0;
91 cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
92
93 ret = set_cpu_freq(freq_Hz);
94
95 cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
96
97 return ret;
98}
99
100static int mxc_cpufreq_init(struct cpufreq_policy *policy)
101{
102 int ret;
103 int i;
104
105 printk(KERN_INFO "i.MXC CPU frequency driver\n");
106
107 if (policy->cpu != 0)
108 return -EINVAL;
109
110 if (!get_cpu_op)
111 return -EINVAL;
112
113 cpu_clk = clk_get(NULL, "cpu_clk");
114 if (IS_ERR(cpu_clk)) {
115 printk(KERN_ERR "%s: failed to get cpu clock\n", __func__);
116 return PTR_ERR(cpu_clk);
117 }
118
119 cpu_op_tbl = get_cpu_op(&cpu_op_nr);
120
121 cpu_freq_khz_min = cpu_op_tbl[0].cpu_rate / 1000;
122 cpu_freq_khz_max = cpu_op_tbl[0].cpu_rate / 1000;
123
124 imx_freq_table = kmalloc(
125 sizeof(struct cpufreq_frequency_table) * (cpu_op_nr + 1),
126 GFP_KERNEL);
127 if (!imx_freq_table) {
128 ret = -ENOMEM;
129 goto err1;
130 }
131
132 for (i = 0; i < cpu_op_nr; i++) {
133 imx_freq_table[i].index = i;
134 imx_freq_table[i].frequency = cpu_op_tbl[i].cpu_rate / 1000;
135
136 if ((cpu_op_tbl[i].cpu_rate / 1000) < cpu_freq_khz_min)
137 cpu_freq_khz_min = cpu_op_tbl[i].cpu_rate / 1000;
138
139 if ((cpu_op_tbl[i].cpu_rate / 1000) > cpu_freq_khz_max)
140 cpu_freq_khz_max = cpu_op_tbl[i].cpu_rate / 1000;
141 }
142
143 imx_freq_table[i].index = i;
144 imx_freq_table[i].frequency = CPUFREQ_TABLE_END;
145
146 policy->cur = clk_get_rate(cpu_clk) / 1000;
147
148 /* Manual states, that PLL stabilizes in two CLK32 periods */
149 policy->cpuinfo.transition_latency = 2 * NANOSECOND / CLK32_FREQ;
150
151 ret = cpufreq_frequency_table_cpuinfo(policy, imx_freq_table);
152 if (ret < 0) {
153 printk(KERN_ERR "%s: failed to register i.MXC CPUfreq with error code %d\n",
154 __func__, ret);
155 goto err;
156 }
157
158 cpufreq_frequency_table_get_attr(imx_freq_table, policy->cpu);
159 return 0;
160err:
161 kfree(imx_freq_table);
162err1:
163 clk_put(cpu_clk);
164 return ret;
165}
166
167static int mxc_cpufreq_exit(struct cpufreq_policy *policy)
168{
169 cpufreq_frequency_table_put_attr(policy->cpu);
170
171 set_cpu_freq(cpu_freq_khz_max * 1000);
172 clk_put(cpu_clk);
173 kfree(imx_freq_table);
174 return 0;
175}
176
177static struct cpufreq_driver mxc_driver = {
178 .flags = CPUFREQ_STICKY,
179 .verify = mxc_verify_speed,
180 .target = mxc_set_target,
181 .get = mxc_get_speed,
182 .init = mxc_cpufreq_init,
183 .exit = mxc_cpufreq_exit,
184 .name = "imx",
185};
186
187static int mxc_cpufreq_driver_init(void)
188{
189 return cpufreq_register_driver(&mxc_driver);
190}
191
192static void mxc_cpufreq_driver_exit(void)
193{
194 cpufreq_unregister_driver(&mxc_driver);
195}
196
197module_init(mxc_cpufreq_driver_init);
198module_exit(mxc_cpufreq_driver_exit);
199
200MODULE_AUTHOR("Freescale Semiconductor Inc. Yong Shen <yong.shen@linaro.org>");
201MODULE_DESCRIPTION("CPUfreq driver for i.MX");
202MODULE_LICENSE("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2025-09-11 17:17:38 -0400