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
|
/*
* linux/arch/arm/mach-integrator/cpu.c
*
* Copyright (C) 2001-2002 Deep Blue Solutions Ltd.
*
* $Id: cpu.c,v 1.6 2002/07/18 13:58:51 rmk Exp $
*
* 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/slab.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <asm/arch/hardware.h>
#include <asm/io.h>
#include <asm/mach-types.h>
#include <asm/hardware/icst525.h>
static struct cpufreq_driver integrator_driver;
#define CM_ID (IO_ADDRESS(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_ID_OFFSET)
#define CM_OSC (IO_ADDRESS(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_OSC_OFFSET)
#define CM_STAT (IO_ADDRESS(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_STAT_OFFSET)
#define CM_LOCK (IO_ADDRESS(INTEGRATOR_HDR_BASE)+INTEGRATOR_HDR_LOCK_OFFSET)
static const struct icst525_params lclk_params = {
.ref = 24000,
.vco_max = 320000,
.vd_min = 8,
.vd_max = 132,
.rd_min = 24,
.rd_max = 24,
};
static const struct icst525_params cclk_params = {
.ref = 24000,
.vco_max = 320000,
.vd_min = 12,
.vd_max = 160,
.rd_min = 24,
.rd_max = 24,
};
/*
* Validate the speed policy.
*/
static int integrator_verify_policy(struct cpufreq_policy *policy)
{
struct icst525_vco vco;
cpufreq_verify_within_limits(policy,
policy->cpuinfo.min_freq,
policy->cpuinfo.max_freq);
vco = icst525_khz_to_vco(&cclk_params, policy->max);
policy->max = icst525_khz(&cclk_params, vco);
vco = icst525_khz_to_vco(&cclk_params, policy->min);
policy->min = icst525_khz(&cclk_params, vco);
cpufreq_verify_within_limits(policy,
policy->cpuinfo.min_freq,
policy->cpuinfo.max_freq);
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 icst525_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(current, cpumask_of_cpu(cpu));
BUG_ON(cpu != smp_processor_id());
/* get current setting */
cm_osc = __raw_readl(CM_OSC);
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 = icst525_khz(&cclk_params, vco);
/* icst525_khz_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 = icst525_khz_to_vco(&cclk_params, target_freq);
freqs.new = icst525_khz(&cclk_params, vco);
freqs.cpu = policy->cpu;
if (freqs.old == freqs.new) {
set_cpus_allowed(current, cpus_allowed);
return 0;
}
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
cm_osc = __raw_readl(CM_OSC);
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_LOCK);
__raw_writel(cm_osc, CM_OSC);
__raw_writel(0, CM_LOCK);
/*
* Restore the CPUs allowed mask.
*/
set_cpus_allowed(current, cpus_allowed);
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
return 0;
}
static unsigned int integrator_get(unsigned int cpu)
{
cpumask_t cpus_allowed;
unsigned int current_freq;
u_int cm_osc;
struct icst525_vco vco;
cpus_allowed = current->cpus_allowed;
set_cpus_allowed(current, cpumask_of_cpu(cpu));
BUG_ON(cpu != smp_processor_id());
/* detect memory etc. */
cm_osc = __raw_readl(CM_OSC);
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;
current_freq = icst525_khz(&cclk_params, vco); /* current freq */
set_cpus_allowed(current, cpus_allowed);
return current_freq;
}
static int integrator_cpufreq_init(struct cpufreq_policy *policy)
{
/* set default policy and cpuinfo */
policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
policy->cpuinfo.max_freq = 160000;
policy->cpuinfo.min_freq = 12000;
policy->cpuinfo.transition_latency = 1000000; /* 1 ms, assumed */
policy->cur = policy->min = policy->max = integrator_get(policy->cpu);
return 0;
}
static struct cpufreq_driver integrator_driver = {
.verify = integrator_verify_policy,
.target = integrator_set_target,
.get = integrator_get,
.init = integrator_cpufreq_init,
.name = "integrator",
};
static int __init integrator_cpu_init(void)
{
return cpufreq_register_driver(&integrator_driver);
}
static void __exit integrator_cpu_exit(void)
{
cpufreq_unregister_driver(&integrator_driver);
}
MODULE_AUTHOR ("Russell M. King");
MODULE_DESCRIPTION ("cpufreq driver for ARM Integrator CPUs");
MODULE_LICENSE ("GPL");
module_init(integrator_cpu_init);
module_exit(integrator_cpu_exit);
|
