diff options
author | Shawn Guo <shawn.guo@linaro.org> | 2012-09-13 07:48:07 -0400 |
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committer | Shawn Guo <shawn.guo@linaro.org> | 2012-10-14 22:02:19 -0400 |
commit | 3995eb82050a81e11217a0b88b2a5eddd53eb4d6 (patch) | |
tree | b1c04b25317c9dade08d911e8077c8745df8a954 /arch/arm/mach-imx/cpufreq.c | |
parent | e0557c0d1a3a9c38af6777d308f98da12c94e137 (diff) |
ARM: imx: merge plat-mxc into mach-imx
It's really unnecessary to have plat-mxc, and let's merge it into
mach-imx. It's pretty much just a bunch of file renaming and
Kconfig/Makefile merge.
To make the change less invasive, we keep using Kconfig symbol
CONFIG_ARCH_MXC for mach-imx sub-architecture.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arm/mach-imx/cpufreq.c')
-rw-r--r-- | arch/arm/mach-imx/cpufreq.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/cpufreq.c b/arch/arm/mach-imx/cpufreq.c new file mode 100644 index 000000000000..b5b6f8083130 --- /dev/null +++ b/arch/arm/mach-imx/cpufreq.c | |||
@@ -0,0 +1,205 @@ | |||
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 | #include <mach/hardware.h> | ||
26 | |||
27 | #define CLK32_FREQ 32768 | ||
28 | #define NANOSECOND (1000 * 1000 * 1000) | ||
29 | |||
30 | struct cpu_op *(*get_cpu_op)(int *op); | ||
31 | |||
32 | static int cpu_freq_khz_min; | ||
33 | static int cpu_freq_khz_max; | ||
34 | |||
35 | static struct clk *cpu_clk; | ||
36 | static struct cpufreq_frequency_table *imx_freq_table; | ||
37 | |||
38 | static int cpu_op_nr; | ||
39 | static struct cpu_op *cpu_op_tbl; | ||
40 | |||
41 | static int set_cpu_freq(int freq) | ||
42 | { | ||
43 | int ret = 0; | ||
44 | int org_cpu_rate; | ||
45 | |||
46 | org_cpu_rate = clk_get_rate(cpu_clk); | ||
47 | if (org_cpu_rate == freq) | ||
48 | return ret; | ||
49 | |||
50 | ret = clk_set_rate(cpu_clk, freq); | ||
51 | if (ret != 0) { | ||
52 | printk(KERN_DEBUG "cannot set CPU clock rate\n"); | ||
53 | return ret; | ||
54 | } | ||
55 | |||
56 | return ret; | ||
57 | } | ||
58 | |||
59 | static int mxc_verify_speed(struct cpufreq_policy *policy) | ||
60 | { | ||
61 | if (policy->cpu != 0) | ||
62 | return -EINVAL; | ||
63 | |||
64 | return cpufreq_frequency_table_verify(policy, imx_freq_table); | ||
65 | } | ||
66 | |||
67 | static unsigned int mxc_get_speed(unsigned int cpu) | ||
68 | { | ||
69 | if (cpu) | ||
70 | return 0; | ||
71 | |||
72 | return clk_get_rate(cpu_clk) / 1000; | ||
73 | } | ||
74 | |||
75 | static int mxc_set_target(struct cpufreq_policy *policy, | ||
76 | unsigned int target_freq, unsigned int relation) | ||
77 | { | ||
78 | struct cpufreq_freqs freqs; | ||
79 | int freq_Hz; | ||
80 | int ret = 0; | ||
81 | unsigned int index; | ||
82 | |||
83 | cpufreq_frequency_table_target(policy, imx_freq_table, | ||
84 | target_freq, relation, &index); | ||
85 | freq_Hz = imx_freq_table[index].frequency * 1000; | ||
86 | |||
87 | freqs.old = clk_get_rate(cpu_clk) / 1000; | ||
88 | freqs.new = freq_Hz / 1000; | ||
89 | freqs.cpu = 0; | ||
90 | freqs.flags = 0; | ||
91 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); | ||
92 | |||
93 | ret = set_cpu_freq(freq_Hz); | ||
94 | |||
95 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); | ||
96 | |||
97 | return ret; | ||
98 | } | ||
99 | |||
100 | static 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 | policy->min = policy->cpuinfo.min_freq = cpu_freq_khz_min; | ||
148 | policy->max = policy->cpuinfo.max_freq = cpu_freq_khz_max; | ||
149 | |||
150 | /* Manual states, that PLL stabilizes in two CLK32 periods */ | ||
151 | policy->cpuinfo.transition_latency = 2 * NANOSECOND / CLK32_FREQ; | ||
152 | |||
153 | ret = cpufreq_frequency_table_cpuinfo(policy, imx_freq_table); | ||
154 | |||
155 | if (ret < 0) { | ||
156 | printk(KERN_ERR "%s: failed to register i.MXC CPUfreq with error code %d\n", | ||
157 | __func__, ret); | ||
158 | goto err; | ||
159 | } | ||
160 | |||
161 | cpufreq_frequency_table_get_attr(imx_freq_table, policy->cpu); | ||
162 | return 0; | ||
163 | err: | ||
164 | kfree(imx_freq_table); | ||
165 | err1: | ||
166 | clk_put(cpu_clk); | ||
167 | return ret; | ||
168 | } | ||
169 | |||
170 | static int mxc_cpufreq_exit(struct cpufreq_policy *policy) | ||
171 | { | ||
172 | cpufreq_frequency_table_put_attr(policy->cpu); | ||
173 | |||
174 | set_cpu_freq(cpu_freq_khz_max * 1000); | ||
175 | clk_put(cpu_clk); | ||
176 | kfree(imx_freq_table); | ||
177 | return 0; | ||
178 | } | ||
179 | |||
180 | static struct cpufreq_driver mxc_driver = { | ||
181 | .flags = CPUFREQ_STICKY, | ||
182 | .verify = mxc_verify_speed, | ||
183 | .target = mxc_set_target, | ||
184 | .get = mxc_get_speed, | ||
185 | .init = mxc_cpufreq_init, | ||
186 | .exit = mxc_cpufreq_exit, | ||
187 | .name = "imx", | ||
188 | }; | ||
189 | |||
190 | static int __devinit mxc_cpufreq_driver_init(void) | ||
191 | { | ||
192 | return cpufreq_register_driver(&mxc_driver); | ||
193 | } | ||
194 | |||
195 | static void mxc_cpufreq_driver_exit(void) | ||
196 | { | ||
197 | cpufreq_unregister_driver(&mxc_driver); | ||
198 | } | ||
199 | |||
200 | module_init(mxc_cpufreq_driver_init); | ||
201 | module_exit(mxc_cpufreq_driver_exit); | ||
202 | |||
203 | MODULE_AUTHOR("Freescale Semiconductor Inc. Yong Shen <yong.shen@linaro.org>"); | ||
204 | MODULE_DESCRIPTION("CPUfreq driver for i.MX"); | ||
205 | MODULE_LICENSE("GPL"); | ||