blob: b704da404067061a4acd831e78b63572b54afc8c [file] [log] [blame]
Olof Johansson2e0c3372007-04-27 15:46:01 +10001/*
2 * Copyright (C) 2007 PA Semi, Inc
3 *
4 * Authors: Egor Martovetsky <egor@pasemi.com>
5 * Olof Johansson <olof@lixom.net>
6 *
7 * Maintained by: Olof Johansson <olof@lixom.net>
8 *
9 * Based on arch/powerpc/platforms/cell/cbe_cpufreq.c:
10 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
15 * any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 *
26 */
27
28#include <linux/cpufreq.h>
29#include <linux/timer.h>
Paul Gortmaker7dfe2932011-05-27 13:23:32 -040030#include <linux/module.h>
Olof Johansson2e0c3372007-04-27 15:46:01 +100031
32#include <asm/hw_irq.h>
33#include <asm/io.h>
34#include <asm/prom.h>
Olof Johansson2abb7012007-05-04 14:39:21 +100035#include <asm/time.h>
Olof Johansson8b32bc02007-11-07 09:26:06 -060036#include <asm/smp.h>
Olof Johansson2e0c3372007-04-27 15:46:01 +100037
38#define SDCASR_REG 0x0100
39#define SDCASR_REG_STRIDE 0x1000
40#define SDCPWR_CFGA0_REG 0x0100
41#define SDCPWR_PWST0_REG 0x0000
42#define SDCPWR_GIZTIME_REG 0x0440
43
44/* SDCPWR_GIZTIME_REG fields */
45#define SDCPWR_GIZTIME_GR 0x80000000
46#define SDCPWR_GIZTIME_LONGLOCK 0x000000ff
47
48/* Offset of ASR registers from SDC base */
49#define SDCASR_OFFSET 0x120000
50
51static void __iomem *sdcpwr_mapbase;
52static void __iomem *sdcasr_mapbase;
53
54static DEFINE_MUTEX(pas_switch_mutex);
55
56/* Current astate, is used when waking up from power savings on
57 * one core, in case the other core has switched states during
58 * the idle time.
59 */
60static int current_astate;
61
62/* We support 5(A0-A4) power states excluding turbo(A5-A6) modes */
63static struct cpufreq_frequency_table pas_freqs[] = {
64 {0, 0},
65 {1, 0},
66 {2, 0},
67 {3, 0},
68 {4, 0},
69 {0, CPUFREQ_TABLE_END},
70};
71
72static struct freq_attr *pas_cpu_freqs_attr[] = {
73 &cpufreq_freq_attr_scaling_available_freqs,
74 NULL,
75};
76
77/*
78 * hardware specific functions
79 */
80
81static int get_astate_freq(int astate)
82{
83 u32 ret;
84 ret = in_le32(sdcpwr_mapbase + SDCPWR_CFGA0_REG + (astate * 0x10));
85
86 return ret & 0x3f;
87}
88
89static int get_cur_astate(int cpu)
90{
91 u32 ret;
92
93 ret = in_le32(sdcpwr_mapbase + SDCPWR_PWST0_REG);
94 ret = (ret >> (cpu * 4)) & 0x7;
95
96 return ret;
97}
98
99static int get_gizmo_latency(void)
100{
101 u32 giztime, ret;
102
103 giztime = in_le32(sdcpwr_mapbase + SDCPWR_GIZTIME_REG);
104
105 /* just provide the upper bound */
106 if (giztime & SDCPWR_GIZTIME_GR)
107 ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 128000;
108 else
109 ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 1000;
110
111 return ret;
112}
113
114static void set_astate(int cpu, unsigned int astate)
115{
Ingo Molnarac3f6452009-01-06 14:06:28 +0000116 unsigned long flags;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000117
118 /* Return if called before init has run */
119 if (unlikely(!sdcasr_mapbase))
120 return;
121
122 local_irq_save(flags);
123
124 out_le32(sdcasr_mapbase + SDCASR_REG + SDCASR_REG_STRIDE*cpu, astate);
125
126 local_irq_restore(flags);
127}
128
Olof Johansson8b32bc02007-11-07 09:26:06 -0600129int check_astate(void)
130{
131 return get_cur_astate(hard_smp_processor_id());
132}
133
Olof Johansson2e0c3372007-04-27 15:46:01 +1000134void restore_astate(int cpu)
135{
136 set_astate(cpu, current_astate);
137}
138
139/*
140 * cpufreq functions
141 */
142
143static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy)
144{
Stephen Rothwell12d371a2007-04-29 16:29:08 +1000145 const u32 *max_freqp;
146 u32 max_freq;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000147 int i, cur_astate;
148 struct resource res;
149 struct device_node *cpu, *dn;
150 int err = -ENODEV;
151
152 cpu = of_get_cpu_node(policy->cpu, NULL);
153
154 if (!cpu)
155 goto out;
156
Olof Johansson0d08a842007-11-04 20:57:45 -0600157 dn = of_find_compatible_node(NULL, NULL, "1682m-sdc");
158 if (!dn)
159 dn = of_find_compatible_node(NULL, NULL,
160 "pasemi,pwrficient-sdc");
Olof Johansson2e0c3372007-04-27 15:46:01 +1000161 if (!dn)
162 goto out;
163 err = of_address_to_resource(dn, 0, &res);
164 of_node_put(dn);
165 if (err)
166 goto out;
167 sdcasr_mapbase = ioremap(res.start + SDCASR_OFFSET, 0x2000);
168 if (!sdcasr_mapbase) {
169 err = -EINVAL;
170 goto out;
171 }
172
Olof Johansson0d08a842007-11-04 20:57:45 -0600173 dn = of_find_compatible_node(NULL, NULL, "1682m-gizmo");
174 if (!dn)
175 dn = of_find_compatible_node(NULL, NULL,
176 "pasemi,pwrficient-gizmo");
Olof Johansson2e0c3372007-04-27 15:46:01 +1000177 if (!dn) {
178 err = -ENODEV;
179 goto out_unmap_sdcasr;
180 }
181 err = of_address_to_resource(dn, 0, &res);
182 of_node_put(dn);
183 if (err)
184 goto out_unmap_sdcasr;
185 sdcpwr_mapbase = ioremap(res.start, 0x1000);
186 if (!sdcpwr_mapbase) {
187 err = -EINVAL;
188 goto out_unmap_sdcasr;
189 }
190
191 pr_debug("init cpufreq on CPU %d\n", policy->cpu);
192
Stephen Rothwell12d371a2007-04-29 16:29:08 +1000193 max_freqp = of_get_property(cpu, "clock-frequency", NULL);
194 if (!max_freqp) {
Olof Johansson2e0c3372007-04-27 15:46:01 +1000195 err = -EINVAL;
196 goto out_unmap_sdcpwr;
197 }
198
199 /* we need the freq in kHz */
Stephen Rothwell12d371a2007-04-29 16:29:08 +1000200 max_freq = *max_freqp / 1000;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000201
Stephen Rothwell12d371a2007-04-29 16:29:08 +1000202 pr_debug("max clock-frequency is at %u kHz\n", max_freq);
Olof Johansson2e0c3372007-04-27 15:46:01 +1000203 pr_debug("initializing frequency table\n");
204
205 /* initialize frequency table */
206 for (i=0; pas_freqs[i].frequency!=CPUFREQ_TABLE_END; i++) {
Viresh Kumar50701582013-03-30 16:25:15 +0530207 pas_freqs[i].frequency =
208 get_astate_freq(pas_freqs[i].driver_data) * 100000;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000209 pr_debug("%d: %d\n", i, pas_freqs[i].frequency);
210 }
211
Olof Johansson2e0c3372007-04-27 15:46:01 +1000212 policy->cpuinfo.transition_latency = get_gizmo_latency();
213
214 cur_astate = get_cur_astate(policy->cpu);
215 pr_debug("current astate is at %d\n",cur_astate);
216
217 policy->cur = pas_freqs[cur_astate].frequency;
Anton Blanchard1b095cf2010-04-26 15:32:32 +0000218 cpumask_copy(policy->cpus, cpu_online_mask);
Olof Johansson2e0c3372007-04-27 15:46:01 +1000219
Olof Johansson2abb7012007-05-04 14:39:21 +1000220 ppc_proc_freq = policy->cur * 1000ul;
221
Olof Johansson2e0c3372007-04-27 15:46:01 +1000222 cpufreq_frequency_table_get_attr(pas_freqs, policy->cpu);
223
224 /* this ensures that policy->cpuinfo_min and policy->cpuinfo_max
225 * are set correctly
226 */
227 return cpufreq_frequency_table_cpuinfo(policy, pas_freqs);
228
229out_unmap_sdcpwr:
230 iounmap(sdcpwr_mapbase);
231
232out_unmap_sdcasr:
233 iounmap(sdcasr_mapbase);
234out:
235 return err;
236}
237
238static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy)
239{
Steven Rostedt72640d82013-01-21 17:23:26 +0000240 /*
241 * We don't support CPU hotplug. Don't unmap after the system
242 * has already made it to a running state.
243 */
244 if (system_state != SYSTEM_BOOTING)
245 return 0;
246
Olof Johansson2e0c3372007-04-27 15:46:01 +1000247 if (sdcasr_mapbase)
248 iounmap(sdcasr_mapbase);
249 if (sdcpwr_mapbase)
250 iounmap(sdcpwr_mapbase);
251
252 cpufreq_frequency_table_put_attr(policy->cpu);
253 return 0;
254}
255
256static int pas_cpufreq_verify(struct cpufreq_policy *policy)
257{
258 return cpufreq_frequency_table_verify(policy, pas_freqs);
259}
260
261static int pas_cpufreq_target(struct cpufreq_policy *policy,
262 unsigned int target_freq,
263 unsigned int relation)
264{
265 struct cpufreq_freqs freqs;
266 int pas_astate_new;
267 int i;
268
269 cpufreq_frequency_table_target(policy,
270 pas_freqs,
271 target_freq,
272 relation,
273 &pas_astate_new);
274
275 freqs.old = policy->cur;
276 freqs.new = pas_freqs[pas_astate_new].frequency;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000277
278 mutex_lock(&pas_switch_mutex);
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530279 cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
Olof Johansson2e0c3372007-04-27 15:46:01 +1000280
281 pr_debug("setting frequency for cpu %d to %d kHz, 1/%d of max frequency\n",
282 policy->cpu,
283 pas_freqs[pas_astate_new].frequency,
Viresh Kumar50701582013-03-30 16:25:15 +0530284 pas_freqs[pas_astate_new].driver_data);
Olof Johansson2e0c3372007-04-27 15:46:01 +1000285
286 current_astate = pas_astate_new;
287
288 for_each_online_cpu(i)
289 set_astate(i, pas_astate_new);
290
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530291 cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
Olof Johansson2e0c3372007-04-27 15:46:01 +1000292 mutex_unlock(&pas_switch_mutex);
293
Olof Johansson2abb7012007-05-04 14:39:21 +1000294 ppc_proc_freq = freqs.new * 1000ul;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000295 return 0;
296}
297
298static struct cpufreq_driver pas_cpufreq_driver = {
299 .name = "pas-cpufreq",
300 .owner = THIS_MODULE,
301 .flags = CPUFREQ_CONST_LOOPS,
302 .init = pas_cpufreq_cpu_init,
303 .exit = pas_cpufreq_cpu_exit,
304 .verify = pas_cpufreq_verify,
305 .target = pas_cpufreq_target,
306 .attr = pas_cpu_freqs_attr,
307};
308
309/*
310 * module init and destoy
311 */
312
313static int __init pas_cpufreq_init(void)
314{
Grant Likely71a157e2010-02-01 21:34:14 -0700315 if (!of_machine_is_compatible("PA6T-1682M") &&
316 !of_machine_is_compatible("pasemi,pwrficient"))
Olof Johansson2e0c3372007-04-27 15:46:01 +1000317 return -ENODEV;
318
319 return cpufreq_register_driver(&pas_cpufreq_driver);
320}
321
322static void __exit pas_cpufreq_exit(void)
323{
324 cpufreq_unregister_driver(&pas_cpufreq_driver);
325}
326
327module_init(pas_cpufreq_init);
328module_exit(pas_cpufreq_exit);
329
330MODULE_LICENSE("GPL");
331MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>, Olof Johansson <olof@lixom.net>");