1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
|
/*
* Copyright (C) 2001-2002 Deep Blue Solutions Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* CPU support functions
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/cpufreq.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <asm/mach-types.h>
#include <asm/hardware/icst.h>
static void __iomem *cm_base;
/* The cpufreq driver only use the OSC register */
#define INTEGRATOR_HDR_OSC_OFFSET 0x08
#define INTEGRATOR_HDR_LOCK_OFFSET 0x14
static struct cpufreq_driver integrator_driver;
static const struct icst_params lclk_params = {
.ref = 24000000,
.vco_max = ICST525_VCO_MAX_5V,
.vco_min = ICST525_VCO_MIN,
.vd_min = 8,
.vd_max = 132,
.rd_min = 24,
.rd_max = 24,
.s2div = icst525_s2div,
.idx2s = icst525_idx2s,
};
static const struct icst_params cclk_params = {
.ref = 24000000,
.vco_max = ICST525_VCO_MAX_5V,
.vco_min = ICST525_VCO_MIN,
.vd_min = 12,
.vd_max = 160,
.rd_min = 24,
.rd_max = 24,
.s2div = icst525_s2div,
.idx2s = icst525_idx2s,
};
/*
* Validate the speed policy.
*/
static int integrator_verify_policy(struct cpufreq_policy *policy)
{
struct icst_vco vco;
cpufreq_verify_within_cpu_limits(policy);
vco = icst_hz_to_vco(&cclk_params, policy->max * 1000);
policy->max = icst_hz(&cclk_params, vco) / 1000;
vco = icst_hz_to_vco(&cclk_params, policy->min * 1000);
policy->min = icst_hz(&cclk_params, vco) / 1000;
cpufreq_verify_within_cpu_limits(policy);
return 0;
}
static int integrator_set_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
cpumask_t cpus_allowed;
int cpu = policy->cpu;
struct icst_vco vco;
struct cpufreq_freqs freqs;
u_int cm_osc;
/*
* Save this threads cpus_allowed mask.
*/
cpus_allowed = current->cpus_allowed;
/*
* Bind to the specified CPU. When this call returns,
* we should be running on the right CPU.
*/
set_cpus_allowed_ptr(current, cpumask_of(cpu));
BUG_ON(cpu != smp_processor_id());
/* get current setting */
cm_osc = __raw_readl(cm_base + INTEGRATOR_HDR_OSC_OFFSET);
if (machine_is_integrator())
vco.s = (cm_osc >> 8) & 7;
else if (machine_is_cintegrator())
vco.s = 1;
vco.v = cm_osc & 255;
vco.r = 22;
freqs.old = icst_hz(&cclk_params, vco) / 1000;
/* icst_hz_to_vco rounds down -- so we need the next
* larger freq in case of CPUFREQ_RELATION_L.
*/
if (relation == CPUFREQ_RELATION_L)
target_freq += 999;
if (target_freq > policy->max)
target_freq = policy->max;
vco = icst_hz_to_vco(&cclk_params, target_freq * 1000);
freqs.new = icst_hz(&cclk_params, vco) / 1000;
if (freqs.old == freqs.new) {
set_cpus_allowed_ptr(current, &cpus_allowed);
return 0;
}
cpufreq_freq_transition_begin(policy, &freqs);
cm_osc = __raw_readl(cm_base + INTEGRATOR_HDR_OSC_OFFSET);
if (machine_is_integrator()) {
cm_osc &= 0xfffff800;
cm_osc |= vco.s << 8;
} else if (machine_is_cintegrator()) {
cm_osc &= 0xffffff00;
}
cm_osc |= vco.v;
__raw_writel(0xa05f, cm_base + INTEGRATOR_HDR_LOCK_OFFSET);
__raw_writel(cm_osc, cm_base + INTEGRATOR_HDR_OSC_OFFSET);
__raw_writel(0, cm_base + INTEGRATOR_HDR_LOCK_OFFSET);
/*
* Restore the CPUs allowed mask.
*/
set_cpus_allowed_ptr(current, &cpus_allowed);
cpufreq_freq_transition_end(policy, &freqs, 0);
return 0;
}
static unsigned int integrator_get(unsigned int cpu)
{
cpumask_t cpus_allowed;
unsigned int current_freq;
u_int cm_osc;
struct icst_vco vco;
cpus_allowed = current->cpus_allowed;
set_cpus_allowed_ptr(current, cpumask_of(cpu));
BUG_ON(cpu != smp_processor_id());
/* detect memory etc. */
cm_osc = __raw_readl(cm_base + INTEGRATOR_HDR_OSC_OFFSET);
if (machine_is_integrator())
vco.s = (cm_osc >> 8) & 7;
else
vco.s = 1;
vco.v = cm_osc & 255;
vco.r = 22;
current_freq = icst_hz(&cclk_params, vco) / 1000; /* current freq */
set_cpus_allowed_ptr(current, &cpus_allowed);
return current_freq;
}
static int integrator_cpufreq_init(struct cpufreq_policy *policy)
{
/* set default policy and cpuinfo */
policy->max = policy->cpuinfo.max_freq = 160000;
policy->min = policy->cpuinfo.min_freq = 12000;
policy->cpuinfo.transition_latency = 1000000; /* 1 ms, assumed */
return 0;
}
static struct cpufreq_driver integrator_driver = {
.flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK,
.verify = integrator_verify_policy,
.target = integrator_set_target,
.get = integrator_get,
.init = integrator_cpufreq_init,
.name = "integrator",
};
static int __init integrator_cpufreq_probe(struct platform_device *pdev)
{
struct resource *res;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
cm_base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
if (!cm_base)
return -ENODEV;
return cpufreq_register_driver(&integrator_driver);
}
static int __exit integrator_cpufreq_remove(struct platform_device *pdev)
{
return cpufreq_unregister_driver(&integrator_driver);
}
static const struct of_device_id integrator_cpufreq_match[] = {
{ .compatible = "arm,core-module-integrator"},
{ },
};
static struct platform_driver integrator_cpufreq_driver = {
.driver = {
.name = "integrator-cpufreq",
.of_match_table = integrator_cpufreq_match,
},
.remove = __exit_p(integrator_cpufreq_remove),
};
module_platform_driver_probe(integrator_cpufreq_driver,
integrator_cpufreq_probe);
MODULE_AUTHOR("Russell M. King");
MODULE_DESCRIPTION("cpufreq driver for ARM Integrator CPUs");
MODULE_LICENSE("GPL");
|
