blob: 84c84b5f0f3a426d70738730b8715defc18bec20 [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>
Rob Herring5af50732013-09-17 14:28:33 -050031#include <linux/of_address.h>
Olof Johansson2e0c3372007-04-27 15:46:01 +100032
33#include <asm/hw_irq.h>
34#include <asm/io.h>
35#include <asm/prom.h>
Olof Johansson2abb7012007-05-04 14:39:21 +100036#include <asm/time.h>
Olof Johansson8b32bc02007-11-07 09:26:06 -060037#include <asm/smp.h>
Olof Johansson2e0c3372007-04-27 15:46:01 +100038
39#define SDCASR_REG 0x0100
40#define SDCASR_REG_STRIDE 0x1000
41#define SDCPWR_CFGA0_REG 0x0100
42#define SDCPWR_PWST0_REG 0x0000
43#define SDCPWR_GIZTIME_REG 0x0440
44
45/* SDCPWR_GIZTIME_REG fields */
46#define SDCPWR_GIZTIME_GR 0x80000000
47#define SDCPWR_GIZTIME_LONGLOCK 0x000000ff
48
49/* Offset of ASR registers from SDC base */
50#define SDCASR_OFFSET 0x120000
51
52static void __iomem *sdcpwr_mapbase;
53static void __iomem *sdcasr_mapbase;
54
Olof Johansson2e0c3372007-04-27 15:46:01 +100055/* Current astate, is used when waking up from power savings on
56 * one core, in case the other core has switched states during
57 * the idle time.
58 */
59static int current_astate;
60
61/* We support 5(A0-A4) power states excluding turbo(A5-A6) modes */
62static struct cpufreq_frequency_table pas_freqs[] = {
Viresh Kumar7f4b0462014-03-28 19:11:47 +053063 {0, 0, 0},
64 {0, 1, 0},
65 {0, 2, 0},
66 {0, 3, 0},
67 {0, 4, 0},
68 {0, 0, CPUFREQ_TABLE_END},
Olof Johansson2e0c3372007-04-27 15:46:01 +100069};
70
Olof Johansson2e0c3372007-04-27 15:46:01 +100071/*
72 * hardware specific functions
73 */
74
75static int get_astate_freq(int astate)
76{
77 u32 ret;
78 ret = in_le32(sdcpwr_mapbase + SDCPWR_CFGA0_REG + (astate * 0x10));
79
80 return ret & 0x3f;
81}
82
83static int get_cur_astate(int cpu)
84{
85 u32 ret;
86
87 ret = in_le32(sdcpwr_mapbase + SDCPWR_PWST0_REG);
88 ret = (ret >> (cpu * 4)) & 0x7;
89
90 return ret;
91}
92
93static int get_gizmo_latency(void)
94{
95 u32 giztime, ret;
96
97 giztime = in_le32(sdcpwr_mapbase + SDCPWR_GIZTIME_REG);
98
99 /* just provide the upper bound */
100 if (giztime & SDCPWR_GIZTIME_GR)
101 ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 128000;
102 else
103 ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 1000;
104
105 return ret;
106}
107
108static void set_astate(int cpu, unsigned int astate)
109{
Ingo Molnarac3f6452009-01-06 14:06:28 +0000110 unsigned long flags;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000111
112 /* Return if called before init has run */
113 if (unlikely(!sdcasr_mapbase))
114 return;
115
116 local_irq_save(flags);
117
118 out_le32(sdcasr_mapbase + SDCASR_REG + SDCASR_REG_STRIDE*cpu, astate);
119
120 local_irq_restore(flags);
121}
122
Olof Johansson8b32bc02007-11-07 09:26:06 -0600123int check_astate(void)
124{
125 return get_cur_astate(hard_smp_processor_id());
126}
127
Olof Johansson2e0c3372007-04-27 15:46:01 +1000128void restore_astate(int cpu)
129{
130 set_astate(cpu, current_astate);
131}
132
133/*
134 * cpufreq functions
135 */
136
137static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy)
138{
Stephen Rothwell12d371a2007-04-29 16:29:08 +1000139 const u32 *max_freqp;
140 u32 max_freq;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000141 int i, cur_astate;
142 struct resource res;
143 struct device_node *cpu, *dn;
144 int err = -ENODEV;
145
146 cpu = of_get_cpu_node(policy->cpu, NULL);
147
148 if (!cpu)
149 goto out;
150
Olof Johansson0d08a842007-11-04 20:57:45 -0600151 dn = of_find_compatible_node(NULL, NULL, "1682m-sdc");
152 if (!dn)
153 dn = of_find_compatible_node(NULL, NULL,
154 "pasemi,pwrficient-sdc");
Olof Johansson2e0c3372007-04-27 15:46:01 +1000155 if (!dn)
156 goto out;
157 err = of_address_to_resource(dn, 0, &res);
158 of_node_put(dn);
159 if (err)
160 goto out;
161 sdcasr_mapbase = ioremap(res.start + SDCASR_OFFSET, 0x2000);
162 if (!sdcasr_mapbase) {
163 err = -EINVAL;
164 goto out;
165 }
166
Olof Johansson0d08a842007-11-04 20:57:45 -0600167 dn = of_find_compatible_node(NULL, NULL, "1682m-gizmo");
168 if (!dn)
169 dn = of_find_compatible_node(NULL, NULL,
170 "pasemi,pwrficient-gizmo");
Olof Johansson2e0c3372007-04-27 15:46:01 +1000171 if (!dn) {
172 err = -ENODEV;
173 goto out_unmap_sdcasr;
174 }
175 err = of_address_to_resource(dn, 0, &res);
176 of_node_put(dn);
177 if (err)
178 goto out_unmap_sdcasr;
179 sdcpwr_mapbase = ioremap(res.start, 0x1000);
180 if (!sdcpwr_mapbase) {
181 err = -EINVAL;
182 goto out_unmap_sdcasr;
183 }
184
185 pr_debug("init cpufreq on CPU %d\n", policy->cpu);
186
Stephen Rothwell12d371a2007-04-29 16:29:08 +1000187 max_freqp = of_get_property(cpu, "clock-frequency", NULL);
188 if (!max_freqp) {
Olof Johansson2e0c3372007-04-27 15:46:01 +1000189 err = -EINVAL;
190 goto out_unmap_sdcpwr;
191 }
192
193 /* we need the freq in kHz */
Stephen Rothwell12d371a2007-04-29 16:29:08 +1000194 max_freq = *max_freqp / 1000;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000195
Stephen Rothwell12d371a2007-04-29 16:29:08 +1000196 pr_debug("max clock-frequency is at %u kHz\n", max_freq);
Olof Johansson2e0c3372007-04-27 15:46:01 +1000197 pr_debug("initializing frequency table\n");
198
199 /* initialize frequency table */
200 for (i=0; pas_freqs[i].frequency!=CPUFREQ_TABLE_END; i++) {
Viresh Kumar50701582013-03-30 16:25:15 +0530201 pas_freqs[i].frequency =
202 get_astate_freq(pas_freqs[i].driver_data) * 100000;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000203 pr_debug("%d: %d\n", i, pas_freqs[i].frequency);
204 }
205
Olof Johansson2e0c3372007-04-27 15:46:01 +1000206 cur_astate = get_cur_astate(policy->cpu);
207 pr_debug("current astate is at %d\n",cur_astate);
208
209 policy->cur = pas_freqs[cur_astate].frequency;
Olof Johansson2abb7012007-05-04 14:39:21 +1000210 ppc_proc_freq = policy->cur * 1000ul;
211
Viresh Kumare315bb72013-10-03 20:29:19 +0530212 return cpufreq_generic_init(policy, pas_freqs, get_gizmo_latency());
Olof Johansson2e0c3372007-04-27 15:46:01 +1000213
214out_unmap_sdcpwr:
215 iounmap(sdcpwr_mapbase);
216
217out_unmap_sdcasr:
218 iounmap(sdcasr_mapbase);
219out:
220 return err;
221}
222
223static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy)
224{
Steven Rostedt72640d82013-01-21 17:23:26 +0000225 /*
226 * We don't support CPU hotplug. Don't unmap after the system
227 * has already made it to a running state.
228 */
229 if (system_state != SYSTEM_BOOTING)
230 return 0;
231
Olof Johansson2e0c3372007-04-27 15:46:01 +1000232 if (sdcasr_mapbase)
233 iounmap(sdcasr_mapbase);
234 if (sdcpwr_mapbase)
235 iounmap(sdcpwr_mapbase);
236
Olof Johansson2e0c3372007-04-27 15:46:01 +1000237 return 0;
238}
239
Olof Johansson2e0c3372007-04-27 15:46:01 +1000240static int pas_cpufreq_target(struct cpufreq_policy *policy,
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530241 unsigned int pas_astate_new)
Olof Johansson2e0c3372007-04-27 15:46:01 +1000242{
Olof Johansson2e0c3372007-04-27 15:46:01 +1000243 int i;
244
Olof Johansson2e0c3372007-04-27 15:46:01 +1000245 pr_debug("setting frequency for cpu %d to %d kHz, 1/%d of max frequency\n",
246 policy->cpu,
247 pas_freqs[pas_astate_new].frequency,
Viresh Kumar50701582013-03-30 16:25:15 +0530248 pas_freqs[pas_astate_new].driver_data);
Olof Johansson2e0c3372007-04-27 15:46:01 +1000249
250 current_astate = pas_astate_new;
251
252 for_each_online_cpu(i)
253 set_astate(i, pas_astate_new);
254
Viresh Kumard4019f02013-08-14 19:38:24 +0530255 ppc_proc_freq = pas_freqs[pas_astate_new].frequency * 1000ul;
Olof Johansson2e0c3372007-04-27 15:46:01 +1000256 return 0;
257}
258
259static struct cpufreq_driver pas_cpufreq_driver = {
260 .name = "pas-cpufreq",
Olof Johansson2e0c3372007-04-27 15:46:01 +1000261 .flags = CPUFREQ_CONST_LOOPS,
262 .init = pas_cpufreq_cpu_init,
263 .exit = pas_cpufreq_cpu_exit,
Viresh Kumar57174312013-10-03 20:28:15 +0530264 .verify = cpufreq_generic_frequency_table_verify,
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530265 .target_index = pas_cpufreq_target,
Viresh Kumar57174312013-10-03 20:28:15 +0530266 .attr = cpufreq_generic_attr,
Olof Johansson2e0c3372007-04-27 15:46:01 +1000267};
268
269/*
270 * module init and destoy
271 */
272
273static int __init pas_cpufreq_init(void)
274{
Grant Likely71a157e2010-02-01 21:34:14 -0700275 if (!of_machine_is_compatible("PA6T-1682M") &&
276 !of_machine_is_compatible("pasemi,pwrficient"))
Olof Johansson2e0c3372007-04-27 15:46:01 +1000277 return -ENODEV;
278
279 return cpufreq_register_driver(&pas_cpufreq_driver);
280}
281
282static void __exit pas_cpufreq_exit(void)
283{
284 cpufreq_unregister_driver(&pas_cpufreq_driver);
285}
286
287module_init(pas_cpufreq_init);
288module_exit(pas_cpufreq_exit);
289
290MODULE_LICENSE("GPL");
291MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>, Olof Johansson <olof@lixom.net>");