Commit | Line | Data |
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1da177e4 | 1 | /* |
1da177e4 LT |
2 | * cpufreq driver for the SuperH processors. |
3 | * | |
3bccf467 | 4 | * Copyright (C) 2002 - 2012 Paul Mundt |
1da177e4 LT |
5 | * Copyright (C) 2002 M. R. Brown |
6 | * | |
cb5ec75b PM |
7 | * Clock framework bits from arch/avr32/mach-at32ap/cpufreq.c |
8 | * | |
9 | * Copyright (C) 2004-2007 Atmel Corporation | |
10 | * | |
11 | * This file is subject to the terms and conditions of the GNU General Public | |
12 | * License. See the file "COPYING" in the main directory of this archive | |
13 | * for more details. | |
1da177e4 | 14 | */ |
ecbef17a PM |
15 | #define pr_fmt(fmt) "cpufreq: " fmt |
16 | ||
1da177e4 LT |
17 | #include <linux/types.h> |
18 | #include <linux/cpufreq.h> | |
19 | #include <linux/kernel.h> | |
20 | #include <linux/module.h> | |
1da177e4 | 21 | #include <linux/init.h> |
cb5ec75b | 22 | #include <linux/err.h> |
1da177e4 | 23 | #include <linux/cpumask.h> |
ecbef17a | 24 | #include <linux/cpu.h> |
1da177e4 | 25 | #include <linux/smp.h> |
cb5ec75b | 26 | #include <linux/clk.h> |
3bccf467 PM |
27 | #include <linux/percpu.h> |
28 | #include <linux/sh_clk.h> | |
1da177e4 | 29 | |
3bccf467 | 30 | static DEFINE_PER_CPU(struct clk, sh_cpuclk); |
1da177e4 | 31 | |
205dcc1e TG |
32 | struct cpufreq_target { |
33 | struct cpufreq_policy *policy; | |
34 | unsigned int freq; | |
35 | }; | |
36 | ||
cb5ec75b | 37 | static unsigned int sh_cpufreq_get(unsigned int cpu) |
1da177e4 | 38 | { |
3bccf467 | 39 | return (clk_get_rate(&per_cpu(sh_cpuclk, cpu)) + 500) / 1000; |
1da177e4 LT |
40 | } |
41 | ||
205dcc1e | 42 | static long __sh_cpufreq_target(void *arg) |
1da177e4 | 43 | { |
205dcc1e TG |
44 | struct cpufreq_target *target = arg; |
45 | struct cpufreq_policy *policy = target->policy; | |
46 | int cpu = policy->cpu; | |
3bccf467 | 47 | struct clk *cpuclk = &per_cpu(sh_cpuclk, cpu); |
1da177e4 | 48 | struct cpufreq_freqs freqs; |
ecbef17a | 49 | struct device *dev; |
cb5ec75b | 50 | long freq; |
1da177e4 | 51 | |
205dcc1e TG |
52 | if (smp_processor_id() != cpu) |
53 | return -ENODEV; | |
1da177e4 | 54 | |
ecbef17a PM |
55 | dev = get_cpu_device(cpu); |
56 | ||
cb5ec75b | 57 | /* Convert target_freq from kHz to Hz */ |
205dcc1e | 58 | freq = clk_round_rate(cpuclk, target->freq * 1000); |
1da177e4 | 59 | |
cb5ec75b PM |
60 | if (freq < (policy->min * 1000) || freq > (policy->max * 1000)) |
61 | return -EINVAL; | |
62 | ||
205dcc1e | 63 | dev_dbg(dev, "requested frequency %u Hz\n", target->freq * 1000); |
1da177e4 | 64 | |
cb5ec75b PM |
65 | freqs.old = sh_cpufreq_get(cpu); |
66 | freqs.new = (freq + 500) / 1000; | |
67 | freqs.flags = 0; | |
68 | ||
205dcc1e | 69 | cpufreq_freq_transition_begin(target->policy, &freqs); |
cb5ec75b | 70 | clk_set_rate(cpuclk, freq); |
205dcc1e | 71 | cpufreq_freq_transition_end(target->policy, &freqs, 0); |
1da177e4 | 72 | |
ecbef17a | 73 | dev_dbg(dev, "set frequency %lu Hz\n", freq); |
1da177e4 LT |
74 | return 0; |
75 | } | |
76 | ||
205dcc1e TG |
77 | /* |
78 | * Here we notify other drivers of the proposed change and the final change. | |
79 | */ | |
80 | static int sh_cpufreq_target(struct cpufreq_policy *policy, | |
81 | unsigned int target_freq, | |
82 | unsigned int relation) | |
83 | { | |
84 | struct cpufreq_target data = { .policy = policy, .freq = target_freq }; | |
85 | ||
86 | return work_on_cpu(policy->cpu, __sh_cpufreq_target, &data); | |
87 | } | |
88 | ||
1e4f63ae | 89 | static int sh_cpufreq_verify(struct cpufreq_policy_data *policy) |
1bcfc723 PM |
90 | { |
91 | struct clk *cpuclk = &per_cpu(sh_cpuclk, policy->cpu); | |
92 | struct cpufreq_frequency_table *freq_table; | |
93 | ||
94 | freq_table = cpuclk->nr_freqs ? cpuclk->freq_table : NULL; | |
95 | if (freq_table) | |
96 | return cpufreq_frequency_table_verify(policy, freq_table); | |
97 | ||
be49e346 | 98 | cpufreq_verify_within_cpu_limits(policy); |
1bcfc723 PM |
99 | |
100 | policy->min = (clk_round_rate(cpuclk, 1) + 500) / 1000; | |
101 | policy->max = (clk_round_rate(cpuclk, ~0UL) + 500) / 1000; | |
102 | ||
be49e346 | 103 | cpufreq_verify_within_cpu_limits(policy); |
1bcfc723 PM |
104 | return 0; |
105 | } | |
106 | ||
1da177e4 LT |
107 | static int sh_cpufreq_cpu_init(struct cpufreq_policy *policy) |
108 | { | |
3bccf467 PM |
109 | unsigned int cpu = policy->cpu; |
110 | struct clk *cpuclk = &per_cpu(sh_cpuclk, cpu); | |
1bcfc723 | 111 | struct cpufreq_frequency_table *freq_table; |
ecbef17a | 112 | struct device *dev; |
3bccf467 | 113 | |
ecbef17a PM |
114 | dev = get_cpu_device(cpu); |
115 | ||
116 | cpuclk = clk_get(dev, "cpu_clk"); | |
cb5ec75b | 117 | if (IS_ERR(cpuclk)) { |
ecbef17a | 118 | dev_err(dev, "couldn't get CPU clk\n"); |
cb5ec75b PM |
119 | return PTR_ERR(cpuclk); |
120 | } | |
1da177e4 | 121 | |
1bcfc723 PM |
122 | freq_table = cpuclk->nr_freqs ? cpuclk->freq_table : NULL; |
123 | if (freq_table) { | |
ec8d2cc6 | 124 | policy->freq_table = freq_table; |
1bcfc723 | 125 | } else { |
1a565cf0 PM |
126 | dev_notice(dev, "no frequency table found, falling back " |
127 | "to rate rounding.\n"); | |
128 | ||
eb2f50ff | 129 | policy->min = policy->cpuinfo.min_freq = |
1a565cf0 | 130 | (clk_round_rate(cpuclk, 1) + 500) / 1000; |
eb2f50ff | 131 | policy->max = policy->cpuinfo.max_freq = |
1a565cf0 | 132 | (clk_round_rate(cpuclk, ~0UL) + 500) / 1000; |
cb5ec75b | 133 | } |
1da177e4 | 134 | |
cb5ec75b PM |
135 | return 0; |
136 | } | |
1da177e4 | 137 | |
1bcfc723 | 138 | static int sh_cpufreq_cpu_exit(struct cpufreq_policy *policy) |
cb5ec75b | 139 | { |
1bcfc723 PM |
140 | unsigned int cpu = policy->cpu; |
141 | struct clk *cpuclk = &per_cpu(sh_cpuclk, cpu); | |
cb5ec75b | 142 | |
cb5ec75b | 143 | clk_put(cpuclk); |
1bcfc723 | 144 | |
1da177e4 LT |
145 | return 0; |
146 | } | |
147 | ||
148 | static struct cpufreq_driver sh_cpufreq_driver = { | |
cb5ec75b | 149 | .name = "sh", |
fe829ed8 | 150 | .flags = CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING, |
cb5ec75b | 151 | .get = sh_cpufreq_get, |
1bcfc723 PM |
152 | .target = sh_cpufreq_target, |
153 | .verify = sh_cpufreq_verify, | |
154 | .init = sh_cpufreq_cpu_init, | |
155 | .exit = sh_cpufreq_cpu_exit, | |
a8f64dec | 156 | .attr = cpufreq_generic_attr, |
1da177e4 LT |
157 | }; |
158 | ||
cb5ec75b | 159 | static int __init sh_cpufreq_module_init(void) |
1da177e4 | 160 | { |
ecbef17a | 161 | pr_notice("SuperH CPU frequency driver.\n"); |
cb5ec75b | 162 | return cpufreq_register_driver(&sh_cpufreq_driver); |
1da177e4 LT |
163 | } |
164 | ||
cb5ec75b | 165 | static void __exit sh_cpufreq_module_exit(void) |
1da177e4 LT |
166 | { |
167 | cpufreq_unregister_driver(&sh_cpufreq_driver); | |
168 | } | |
169 | ||
cb5ec75b PM |
170 | module_init(sh_cpufreq_module_init); |
171 | module_exit(sh_cpufreq_module_exit); | |
1da177e4 LT |
172 | |
173 | MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>"); | |
174 | MODULE_DESCRIPTION("cpufreq driver for SuperH"); | |
175 | MODULE_LICENSE("GPL"); |