Commit | Line | Data |
---|---|---|
7c1a70e9 | 1 | /* |
7c1a70e9 | 2 | * Copyright (C) STMicroelectronics 2009 |
0baf066f | 3 | * Copyright (C) ST-Ericsson SA 2010-2012 |
7c1a70e9 MP |
4 | * |
5 | * License Terms: GNU General Public License v2 | |
7c1a70e9 MP |
6 | * Author: Sundar Iyer <sundar.iyer@stericsson.com> |
7 | * Author: Martin Persson <martin.persson@stericsson.com> | |
8 | * Author: Jonas Aaberg <jonas.aberg@stericsson.com> | |
7c1a70e9 | 9 | */ |
0baf066f | 10 | |
b4689444 | 11 | #include <linux/module.h> |
7c1a70e9 MP |
12 | #include <linux/kernel.h> |
13 | #include <linux/cpufreq.h> | |
14 | #include <linux/delay.h> | |
72b2fd5c | 15 | #include <linux/slab.h> |
b4689444 | 16 | #include <linux/platform_device.h> |
78e30d12 | 17 | #include <linux/clk.h> |
7c1a70e9 | 18 | |
fdb44464 | 19 | static struct cpufreq_frequency_table *freq_table; |
78e30d12 | 20 | static struct clk *armss_clk; |
72b2fd5c | 21 | |
edb10c11 | 22 | static struct freq_attr *dbx500_cpufreq_attr[] = { |
72b2fd5c LW |
23 | &cpufreq_freq_attr_scaling_available_freqs, |
24 | NULL, | |
7c1a70e9 MP |
25 | }; |
26 | ||
edb10c11 | 27 | static int dbx500_cpufreq_verify_speed(struct cpufreq_policy *policy) |
7c1a70e9 MP |
28 | { |
29 | return cpufreq_frequency_table_verify(policy, freq_table); | |
30 | } | |
31 | ||
edb10c11 | 32 | static int dbx500_cpufreq_target(struct cpufreq_policy *policy, |
7c1a70e9 MP |
33 | unsigned int target_freq, |
34 | unsigned int relation) | |
35 | { | |
36 | struct cpufreq_freqs freqs; | |
72b2fd5c | 37 | unsigned int idx; |
9291cf9d | 38 | int ret; |
7c1a70e9 | 39 | |
72b2fd5c | 40 | /* Lookup the next frequency */ |
9291cf9d JA |
41 | if (cpufreq_frequency_table_target(policy, freq_table, target_freq, |
42 | relation, &idx)) | |
72b2fd5c | 43 | return -EINVAL; |
7c1a70e9 MP |
44 | |
45 | freqs.old = policy->cur; | |
72b2fd5c | 46 | freqs.new = freq_table[idx].frequency; |
7c1a70e9 | 47 | |
72b2fd5c | 48 | if (freqs.old == freqs.new) |
7c1a70e9 | 49 | return 0; |
7c1a70e9 | 50 | |
72b2fd5c | 51 | /* pre-change notification */ |
b43a7ffb | 52 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); |
7c1a70e9 | 53 | |
78e30d12 | 54 | /* update armss clk frequency */ |
9291cf9d JA |
55 | ret = clk_set_rate(armss_clk, freqs.new * 1000); |
56 | ||
57 | if (ret) { | |
58 | pr_err("dbx500-cpufreq: Failed to set armss_clk to %d Hz: error %d\n", | |
59 | freqs.new * 1000, ret); | |
803c126a | 60 | freqs.new = freqs.old; |
7c1a70e9 MP |
61 | } |
62 | ||
72b2fd5c | 63 | /* post change notification */ |
b43a7ffb | 64 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); |
7c1a70e9 | 65 | |
803c126a | 66 | return ret; |
7c1a70e9 MP |
67 | } |
68 | ||
edb10c11 | 69 | static unsigned int dbx500_cpufreq_getspeed(unsigned int cpu) |
7c1a70e9 | 70 | { |
fdb44464 | 71 | int i = 0; |
78e30d12 | 72 | unsigned long freq = clk_get_rate(armss_clk) / 1000; |
fdb44464 | 73 | |
c7789669 MF |
74 | /* The value is rounded to closest frequency in the defined table. */ |
75 | while (freq_table[i + 1].frequency != CPUFREQ_TABLE_END) { | |
76 | if (freq < freq_table[i].frequency + | |
77 | (freq_table[i + 1].frequency - freq_table[i].frequency) / 2) | |
fdb44464 UH |
78 | return freq_table[i].frequency; |
79 | i++; | |
80 | } | |
81 | ||
c7789669 | 82 | return freq_table[i].frequency; |
7c1a70e9 MP |
83 | } |
84 | ||
2760984f | 85 | static int dbx500_cpufreq_init(struct cpufreq_policy *policy) |
7c1a70e9 | 86 | { |
fdb44464 | 87 | int res; |
c72fe851 | 88 | |
7c1a70e9 MP |
89 | /* get policy fields based on the table */ |
90 | res = cpufreq_frequency_table_cpuinfo(policy, freq_table); | |
91 | if (!res) | |
92 | cpufreq_frequency_table_get_attr(freq_table, policy->cpu); | |
93 | else { | |
9291cf9d | 94 | pr_err("dbx500-cpufreq: Failed to read policy table\n"); |
7c1a70e9 MP |
95 | return res; |
96 | } | |
97 | ||
98 | policy->min = policy->cpuinfo.min_freq; | |
99 | policy->max = policy->cpuinfo.max_freq; | |
edb10c11 | 100 | policy->cur = dbx500_cpufreq_getspeed(policy->cpu); |
7c1a70e9 MP |
101 | policy->governor = CPUFREQ_DEFAULT_GOVERNOR; |
102 | ||
103 | /* | |
104 | * FIXME : Need to take time measurement across the target() | |
105 | * function with no/some/all drivers in the notification | |
106 | * list. | |
107 | */ | |
72b2fd5c | 108 | policy->cpuinfo.transition_latency = 20 * 1000; /* in ns */ |
7c1a70e9 MP |
109 | |
110 | /* policy sharing between dual CPUs */ | |
4c738d00 | 111 | cpumask_setall(policy->cpus); |
7c1a70e9 | 112 | |
7c1a70e9 MP |
113 | return 0; |
114 | } | |
115 | ||
edb10c11 | 116 | static struct cpufreq_driver dbx500_cpufreq_driver = { |
ec669123 | 117 | .flags = CPUFREQ_STICKY | CPUFREQ_CONST_LOOPS, |
edb10c11 LJ |
118 | .verify = dbx500_cpufreq_verify_speed, |
119 | .target = dbx500_cpufreq_target, | |
120 | .get = dbx500_cpufreq_getspeed, | |
121 | .init = dbx500_cpufreq_init, | |
122 | .name = "DBX500", | |
123 | .attr = dbx500_cpufreq_attr, | |
7c1a70e9 MP |
124 | }; |
125 | ||
edb10c11 | 126 | static int dbx500_cpufreq_probe(struct platform_device *pdev) |
b4689444 | 127 | { |
3e27996c | 128 | int i = 0; |
fdb44464 | 129 | |
3e27996c | 130 | freq_table = dev_get_platdata(&pdev->dev); |
fdb44464 | 131 | if (!freq_table) { |
edb10c11 | 132 | pr_err("dbx500-cpufreq: Failed to fetch cpufreq table\n"); |
fdb44464 UH |
133 | return -ENODEV; |
134 | } | |
135 | ||
3e27996c UH |
136 | armss_clk = clk_get(&pdev->dev, "armss"); |
137 | if (IS_ERR(armss_clk)) { | |
9291cf9d | 138 | pr_err("dbx500-cpufreq: Failed to get armss clk\n"); |
3e27996c UH |
139 | return PTR_ERR(armss_clk); |
140 | } | |
141 | ||
9291cf9d | 142 | pr_info("dbx500-cpufreq: Available frequencies:\n"); |
3e27996c UH |
143 | while (freq_table[i].frequency != CPUFREQ_TABLE_END) { |
144 | pr_info(" %d Mhz\n", freq_table[i].frequency/1000); | |
145 | i++; | |
146 | } | |
147 | ||
edb10c11 | 148 | return cpufreq_register_driver(&dbx500_cpufreq_driver); |
b4689444 UH |
149 | } |
150 | ||
edb10c11 | 151 | static struct platform_driver dbx500_cpufreq_plat_driver = { |
b4689444 | 152 | .driver = { |
edb10c11 | 153 | .name = "cpufreq-ux500", |
b4689444 UH |
154 | .owner = THIS_MODULE, |
155 | }, | |
edb10c11 | 156 | .probe = dbx500_cpufreq_probe, |
b4689444 UH |
157 | }; |
158 | ||
edb10c11 | 159 | static int __init dbx500_cpufreq_register(void) |
7c1a70e9 | 160 | { |
edb10c11 | 161 | return platform_driver_register(&dbx500_cpufreq_plat_driver); |
7c1a70e9 | 162 | } |
edb10c11 | 163 | device_initcall(dbx500_cpufreq_register); |
b4689444 UH |
164 | |
165 | MODULE_LICENSE("GPL v2"); | |
edb10c11 | 166 | MODULE_DESCRIPTION("cpufreq driver for DBX500"); |