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
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2007 PA Semi, Inc
*
* Authors: Egor Martovetsky <egor@pasemi.com>
* Olof Johansson <olof@lixom.net>
*
* Maintained by: Olof Johansson <olof@lixom.net>
*
* Based on arch/powerpc/platforms/cell/cbe_cpufreq.c:
* (C) Copyright IBM Deutschland Entwicklung GmbH 2005
*/
#include <linux/cpufreq.h>
#include <linux/timer.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <asm/hw_irq.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/time.h>
#include <asm/smp.h>
#define SDCASR_REG 0x0100
#define SDCASR_REG_STRIDE 0x1000
#define SDCPWR_CFGA0_REG 0x0100
#define SDCPWR_PWST0_REG 0x0000
#define SDCPWR_GIZTIME_REG 0x0440
/* SDCPWR_GIZTIME_REG fields */
#define SDCPWR_GIZTIME_GR 0x80000000
#define SDCPWR_GIZTIME_LONGLOCK 0x000000ff
/* Offset of ASR registers from SDC base */
#define SDCASR_OFFSET 0x120000
static void __iomem *sdcpwr_mapbase;
static void __iomem *sdcasr_mapbase;
/* Current astate, is used when waking up from power savings on
* one core, in case the other core has switched states during
* the idle time.
*/
static int current_astate;
/* We support 5(A0-A4) power states excluding turbo(A5-A6) modes */
static struct cpufreq_frequency_table pas_freqs[] = {
{0, 0, 0},
{0, 1, 0},
{0, 2, 0},
{0, 3, 0},
{0, 4, 0},
{0, 0, CPUFREQ_TABLE_END},
};
/*
* hardware specific functions
*/
static int get_astate_freq(int astate)
{
u32 ret;
ret = in_le32(sdcpwr_mapbase + SDCPWR_CFGA0_REG + (astate * 0x10));
return ret & 0x3f;
}
static int get_cur_astate(int cpu)
{
u32 ret;
ret = in_le32(sdcpwr_mapbase + SDCPWR_PWST0_REG);
ret = (ret >> (cpu * 4)) & 0x7;
return ret;
}
static int get_gizmo_latency(void)
{
u32 giztime, ret;
giztime = in_le32(sdcpwr_mapbase + SDCPWR_GIZTIME_REG);
/* just provide the upper bound */
if (giztime & SDCPWR_GIZTIME_GR)
ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 128000;
else
ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 1000;
return ret;
}
static void set_astate(int cpu, unsigned int astate)
{
unsigned long flags;
/* Return if called before init has run */
if (unlikely(!sdcasr_mapbase))
return;
local_irq_save(flags);
out_le32(sdcasr_mapbase + SDCASR_REG + SDCASR_REG_STRIDE*cpu, astate);
local_irq_restore(flags);
}
int check_astate(void)
{
return get_cur_astate(hard_smp_processor_id());
}
void restore_astate(int cpu)
{
set_astate(cpu, current_astate);
}
/*
* cpufreq functions
*/
static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
struct cpufreq_frequency_table *pos;
const u32 *max_freqp;
u32 max_freq;
int cur_astate, idx;
struct resource res;
struct device_node *cpu, *dn;
int err = -ENODEV;
cpu = of_get_cpu_node(policy->cpu, NULL);
of_node_put(cpu);
if (!cpu)
goto out;
dn = of_find_compatible_node(NULL, NULL, "1682m-sdc");
if (!dn)
dn = of_find_compatible_node(NULL, NULL,
"pasemi,pwrficient-sdc");
if (!dn)
goto out;
err = of_address_to_resource(dn, 0, &res);
of_node_put(dn);
if (err)
goto out;
sdcasr_mapbase = ioremap(res.start + SDCASR_OFFSET, 0x2000);
if (!sdcasr_mapbase) {
err = -EINVAL;
goto out;
}
dn = of_find_compatible_node(NULL, NULL, "1682m-gizmo");
if (!dn)
dn = of_find_compatible_node(NULL, NULL,
"pasemi,pwrficient-gizmo");
if (!dn) {
err = -ENODEV;
goto out_unmap_sdcasr;
}
err = of_address_to_resource(dn, 0, &res);
of_node_put(dn);
if (err)
goto out_unmap_sdcasr;
sdcpwr_mapbase = ioremap(res.start, 0x1000);
if (!sdcpwr_mapbase) {
err = -EINVAL;
goto out_unmap_sdcasr;
}
pr_debug("init cpufreq on CPU %d\n", policy->cpu);
max_freqp = of_get_property(cpu, "clock-frequency", NULL);
if (!max_freqp) {
err = -EINVAL;
goto out_unmap_sdcpwr;
}
/* we need the freq in kHz */
max_freq = *max_freqp / 1000;
pr_debug("max clock-frequency is at %u kHz\n", max_freq);
pr_debug("initializing frequency table\n");
/* initialize frequency table */
cpufreq_for_each_entry_idx(pos, pas_freqs, idx) {
pos->frequency = get_astate_freq(pos->driver_data) * 100000;
pr_debug("%d: %d\n", idx, pos->frequency);
}
cur_astate = get_cur_astate(policy->cpu);
pr_debug("current astate is at %d\n",cur_astate);
policy->cur = pas_freqs[cur_astate].frequency;
ppc_proc_freq = policy->cur * 1000ul;
cpufreq_generic_init(policy, pas_freqs, get_gizmo_latency());
return 0;
out_unmap_sdcpwr:
iounmap(sdcpwr_mapbase);
out_unmap_sdcasr:
iounmap(sdcasr_mapbase);
out:
return err;
}
static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy)
{
/*
* We don't support CPU hotplug. Don't unmap after the system
* has already made it to a running state.
*/
if (system_state >= SYSTEM_RUNNING)
return 0;
if (sdcasr_mapbase)
iounmap(sdcasr_mapbase);
if (sdcpwr_mapbase)
iounmap(sdcpwr_mapbase);
return 0;
}
static int pas_cpufreq_target(struct cpufreq_policy *policy,
unsigned int pas_astate_new)
{
int i;
pr_debug("setting frequency for cpu %d to %d kHz, 1/%d of max frequency\n",
policy->cpu,
pas_freqs[pas_astate_new].frequency,
pas_freqs[pas_astate_new].driver_data);
current_astate = pas_astate_new;
for_each_online_cpu(i)
set_astate(i, pas_astate_new);
ppc_proc_freq = pas_freqs[pas_astate_new].frequency * 1000ul;
return 0;
}
static struct cpufreq_driver pas_cpufreq_driver = {
.name = "pas-cpufreq",
.flags = CPUFREQ_CONST_LOOPS,
.init = pas_cpufreq_cpu_init,
.exit = pas_cpufreq_cpu_exit,
.verify = cpufreq_generic_frequency_table_verify,
.target_index = pas_cpufreq_target,
.attr = cpufreq_generic_attr,
};
/*
* module init and destoy
*/
static int __init pas_cpufreq_init(void)
{
if (!of_machine_is_compatible("PA6T-1682M") &&
!of_machine_is_compatible("pasemi,pwrficient"))
return -ENODEV;
return cpufreq_register_driver(&pas_cpufreq_driver);
}
static void __exit pas_cpufreq_exit(void)
{
cpufreq_unregister_driver(&pas_cpufreq_driver);
}
module_init(pas_cpufreq_init);
module_exit(pas_cpufreq_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>, Olof Johansson <olof@lixom.net>");
|
