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Commit | Line | Data |
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ec6bced6 | 1 | /* |
ec6bced6 TL |
2 | * CPU frequency scaling for OMAP |
3 | * | |
4 | * Copyright (C) 2005 Nokia Corporation | |
5 | * Written by Tony Lindgren <tony@atomide.com> | |
6 | * | |
7 | * Based on cpu-sa1110.c, Copyright (C) 2001 Russell King | |
8 | * | |
731e0cc6 SS |
9 | * Copyright (C) 2007-2011 Texas Instruments, Inc. |
10 | * - OMAP3/4 support by Rajendra Nayak, Santosh Shilimkar | |
11 | * | |
ec6bced6 TL |
12 | * This program is free software; you can redistribute it and/or modify |
13 | * it under the terms of the GNU General Public License version 2 as | |
14 | * published by the Free Software Foundation. | |
15 | */ | |
16 | #include <linux/types.h> | |
17 | #include <linux/kernel.h> | |
18 | #include <linux/sched.h> | |
19 | #include <linux/cpufreq.h> | |
20 | #include <linux/delay.h> | |
21 | #include <linux/init.h> | |
22 | #include <linux/err.h> | |
f8ce2547 | 23 | #include <linux/clk.h> |
fced80c7 | 24 | #include <linux/io.h> |
731e0cc6 | 25 | #include <linux/opp.h> |
ec6bced6 | 26 | |
ec6bced6 | 27 | #include <asm/system.h> |
731e0cc6 | 28 | #include <asm/smp_plat.h> |
ec6bced6 | 29 | |
731e0cc6 SS |
30 | #include <plat/clock.h> |
31 | #include <plat/omap-pm.h> | |
32 | #include <plat/common.h> | |
a7ca9d2b | 33 | |
731e0cc6 | 34 | #include <mach/hardware.h> |
aeec2990 | 35 | |
731e0cc6 | 36 | #define VERY_HI_RATE 900000000 |
a7ca9d2b | 37 | |
731e0cc6 | 38 | static struct cpufreq_frequency_table *freq_table; |
b8488fbe HD |
39 | static struct clk *mpu_clk; |
40 | ||
b0a330dc | 41 | static int omap_verify_speed(struct cpufreq_policy *policy) |
ec6bced6 | 42 | { |
aeec2990 KH |
43 | if (freq_table) |
44 | return cpufreq_frequency_table_verify(policy, freq_table); | |
45 | ||
ec6bced6 TL |
46 | if (policy->cpu) |
47 | return -EINVAL; | |
48 | ||
49 | cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, | |
50 | policy->cpuinfo.max_freq); | |
b8488fbe | 51 | |
ec6bced6 TL |
52 | policy->min = clk_round_rate(mpu_clk, policy->min * 1000) / 1000; |
53 | policy->max = clk_round_rate(mpu_clk, policy->max * 1000) / 1000; | |
54 | cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, | |
55 | policy->cpuinfo.max_freq); | |
ec6bced6 TL |
56 | return 0; |
57 | } | |
58 | ||
b0a330dc | 59 | static unsigned int omap_getspeed(unsigned int cpu) |
ec6bced6 | 60 | { |
ec6bced6 TL |
61 | unsigned long rate; |
62 | ||
63 | if (cpu) | |
64 | return 0; | |
65 | ||
ec6bced6 | 66 | rate = clk_get_rate(mpu_clk) / 1000; |
ec6bced6 TL |
67 | return rate; |
68 | } | |
69 | ||
70 | static int omap_target(struct cpufreq_policy *policy, | |
71 | unsigned int target_freq, | |
72 | unsigned int relation) | |
73 | { | |
ec6bced6 | 74 | int ret = 0; |
731e0cc6 | 75 | struct cpufreq_freqs freqs; |
ec6bced6 | 76 | |
aeec2990 KH |
77 | /* Ensure desired rate is within allowed range. Some govenors |
78 | * (ondemand) will just pass target_freq=0 to get the minimum. */ | |
60c45ae1 EN |
79 | if (target_freq < policy->min) |
80 | target_freq = policy->min; | |
81 | if (target_freq > policy->max) | |
82 | target_freq = policy->max; | |
aeec2990 | 83 | |
ec6bced6 TL |
84 | freqs.old = omap_getspeed(0); |
85 | freqs.new = clk_round_rate(mpu_clk, target_freq * 1000) / 1000; | |
86 | freqs.cpu = 0; | |
87 | ||
aeec2990 KH |
88 | if (freqs.old == freqs.new) |
89 | return ret; | |
90 | ||
ec6bced6 | 91 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); |
731e0cc6 | 92 | |
aeec2990 | 93 | #ifdef CONFIG_CPU_FREQ_DEBUG |
731e0cc6 | 94 | pr_info("cpufreq-omap: transition: %u --> %u\n", freqs.old, freqs.new); |
aeec2990 | 95 | #endif |
731e0cc6 | 96 | |
aeec2990 | 97 | ret = clk_set_rate(mpu_clk, freqs.new * 1000); |
731e0cc6 | 98 | |
ec6bced6 | 99 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); |
ec6bced6 TL |
100 | |
101 | return ret; | |
102 | } | |
103 | ||
790ab7e9 | 104 | static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy) |
ec6bced6 | 105 | { |
aeec2990 | 106 | int result = 0; |
731e0cc6 SS |
107 | struct device *mpu_dev; |
108 | ||
109 | if (cpu_is_omap24xx()) | |
110 | mpu_clk = clk_get(NULL, "virt_prcm_set"); | |
111 | else if (cpu_is_omap34xx()) | |
112 | mpu_clk = clk_get(NULL, "dpll1_ck"); | |
113 | else if (cpu_is_omap44xx()) | |
114 | mpu_clk = clk_get(NULL, "dpll_mpu_ck"); | |
aeec2990 | 115 | |
ec6bced6 TL |
116 | if (IS_ERR(mpu_clk)) |
117 | return PTR_ERR(mpu_clk); | |
118 | ||
119 | if (policy->cpu != 0) | |
120 | return -EINVAL; | |
aeec2990 | 121 | |
ec6bced6 | 122 | policy->cur = policy->min = policy->max = omap_getspeed(0); |
aeec2990 | 123 | |
731e0cc6 SS |
124 | mpu_dev = omap2_get_mpuss_device(); |
125 | if (!mpu_dev) { | |
126 | pr_warning("%s: unable to get the mpu device\n", __func__); | |
127 | return -EINVAL; | |
128 | } | |
129 | opp_init_cpufreq_table(mpu_dev, &freq_table); | |
130 | ||
aeec2990 KH |
131 | if (freq_table) { |
132 | result = cpufreq_frequency_table_cpuinfo(policy, freq_table); | |
133 | if (!result) | |
134 | cpufreq_frequency_table_get_attr(freq_table, | |
135 | policy->cpu); | |
136 | } else { | |
137 | policy->cpuinfo.min_freq = clk_round_rate(mpu_clk, 0) / 1000; | |
138 | policy->cpuinfo.max_freq = clk_round_rate(mpu_clk, | |
139 | VERY_HI_RATE) / 1000; | |
140 | } | |
141 | ||
731e0cc6 SS |
142 | policy->min = policy->cpuinfo.min_freq; |
143 | policy->max = policy->cpuinfo.max_freq; | |
144 | policy->cur = omap_getspeed(0); | |
145 | ||
aeec2990 | 146 | /* FIXME: what's the actual transition time? */ |
b029839c | 147 | policy->cpuinfo.transition_latency = 300 * 1000; |
ec6bced6 TL |
148 | |
149 | return 0; | |
150 | } | |
151 | ||
b8488fbe HD |
152 | static int omap_cpu_exit(struct cpufreq_policy *policy) |
153 | { | |
4e37c10d | 154 | clk_exit_cpufreq_table(&freq_table); |
b8488fbe HD |
155 | clk_put(mpu_clk); |
156 | return 0; | |
157 | } | |
158 | ||
aeec2990 KH |
159 | static struct freq_attr *omap_cpufreq_attr[] = { |
160 | &cpufreq_freq_attr_scaling_available_freqs, | |
161 | NULL, | |
162 | }; | |
163 | ||
ec6bced6 TL |
164 | static struct cpufreq_driver omap_driver = { |
165 | .flags = CPUFREQ_STICKY, | |
166 | .verify = omap_verify_speed, | |
167 | .target = omap_target, | |
168 | .get = omap_getspeed, | |
169 | .init = omap_cpu_init, | |
b8488fbe | 170 | .exit = omap_cpu_exit, |
ec6bced6 | 171 | .name = "omap", |
aeec2990 | 172 | .attr = omap_cpufreq_attr, |
ec6bced6 TL |
173 | }; |
174 | ||
175 | static int __init omap_cpufreq_init(void) | |
176 | { | |
177 | return cpufreq_register_driver(&omap_driver); | |
178 | } | |
179 | ||
731e0cc6 SS |
180 | static void __exit omap_cpufreq_exit(void) |
181 | { | |
182 | cpufreq_unregister_driver(&omap_driver); | |
183 | } | |
aeec2990 | 184 | |
731e0cc6 SS |
185 | MODULE_DESCRIPTION("cpufreq driver for OMAP SoCs"); |
186 | MODULE_LICENSE("GPL"); | |
187 | module_init(omap_cpufreq_init); | |
188 | module_exit(omap_cpufreq_exit); |