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2e0c3370 OJ |
1 | /* |
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> | |
7dfe293c | 30 | #include <linux/module.h> |
2e0c3370 OJ |
31 | |
32 | #include <asm/hw_irq.h> | |
33 | #include <asm/io.h> | |
34 | #include <asm/prom.h> | |
2abb7019 | 35 | #include <asm/time.h> |
8b32bc03 | 36 | #include <asm/smp.h> |
2e0c3370 OJ |
37 | |
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 | ||
51 | static void __iomem *sdcpwr_mapbase; | |
52 | static void __iomem *sdcasr_mapbase; | |
53 | ||
54 | static 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 | */ | |
60 | static int current_astate; | |
61 | ||
62 | /* We support 5(A0-A4) power states excluding turbo(A5-A6) modes */ | |
63 | static 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 | ||
2e0c3370 OJ |
72 | /* |
73 | * hardware specific functions | |
74 | */ | |
75 | ||
76 | static int get_astate_freq(int astate) | |
77 | { | |
78 | u32 ret; | |
79 | ret = in_le32(sdcpwr_mapbase + SDCPWR_CFGA0_REG + (astate * 0x10)); | |
80 | ||
81 | return ret & 0x3f; | |
82 | } | |
83 | ||
84 | static int get_cur_astate(int cpu) | |
85 | { | |
86 | u32 ret; | |
87 | ||
88 | ret = in_le32(sdcpwr_mapbase + SDCPWR_PWST0_REG); | |
89 | ret = (ret >> (cpu * 4)) & 0x7; | |
90 | ||
91 | return ret; | |
92 | } | |
93 | ||
94 | static int get_gizmo_latency(void) | |
95 | { | |
96 | u32 giztime, ret; | |
97 | ||
98 | giztime = in_le32(sdcpwr_mapbase + SDCPWR_GIZTIME_REG); | |
99 | ||
100 | /* just provide the upper bound */ | |
101 | if (giztime & SDCPWR_GIZTIME_GR) | |
102 | ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 128000; | |
103 | else | |
104 | ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 1000; | |
105 | ||
106 | return ret; | |
107 | } | |
108 | ||
109 | static void set_astate(int cpu, unsigned int astate) | |
110 | { | |
ac3f6454 | 111 | unsigned long flags; |
2e0c3370 OJ |
112 | |
113 | /* Return if called before init has run */ | |
114 | if (unlikely(!sdcasr_mapbase)) | |
115 | return; | |
116 | ||
117 | local_irq_save(flags); | |
118 | ||
119 | out_le32(sdcasr_mapbase + SDCASR_REG + SDCASR_REG_STRIDE*cpu, astate); | |
120 | ||
121 | local_irq_restore(flags); | |
122 | } | |
123 | ||
8b32bc03 OJ |
124 | int check_astate(void) |
125 | { | |
126 | return get_cur_astate(hard_smp_processor_id()); | |
127 | } | |
128 | ||
2e0c3370 OJ |
129 | void restore_astate(int cpu) |
130 | { | |
131 | set_astate(cpu, current_astate); | |
132 | } | |
133 | ||
134 | /* | |
135 | * cpufreq functions | |
136 | */ | |
137 | ||
138 | static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) | |
139 | { | |
12d371a6 SR |
140 | const u32 *max_freqp; |
141 | u32 max_freq; | |
2e0c3370 OJ |
142 | int i, cur_astate; |
143 | struct resource res; | |
144 | struct device_node *cpu, *dn; | |
145 | int err = -ENODEV; | |
146 | ||
147 | cpu = of_get_cpu_node(policy->cpu, NULL); | |
148 | ||
149 | if (!cpu) | |
150 | goto out; | |
151 | ||
0d08a847 OJ |
152 | dn = of_find_compatible_node(NULL, NULL, "1682m-sdc"); |
153 | if (!dn) | |
154 | dn = of_find_compatible_node(NULL, NULL, | |
155 | "pasemi,pwrficient-sdc"); | |
2e0c3370 OJ |
156 | if (!dn) |
157 | goto out; | |
158 | err = of_address_to_resource(dn, 0, &res); | |
159 | of_node_put(dn); | |
160 | if (err) | |
161 | goto out; | |
162 | sdcasr_mapbase = ioremap(res.start + SDCASR_OFFSET, 0x2000); | |
163 | if (!sdcasr_mapbase) { | |
164 | err = -EINVAL; | |
165 | goto out; | |
166 | } | |
167 | ||
0d08a847 OJ |
168 | dn = of_find_compatible_node(NULL, NULL, "1682m-gizmo"); |
169 | if (!dn) | |
170 | dn = of_find_compatible_node(NULL, NULL, | |
171 | "pasemi,pwrficient-gizmo"); | |
2e0c3370 OJ |
172 | if (!dn) { |
173 | err = -ENODEV; | |
174 | goto out_unmap_sdcasr; | |
175 | } | |
176 | err = of_address_to_resource(dn, 0, &res); | |
177 | of_node_put(dn); | |
178 | if (err) | |
179 | goto out_unmap_sdcasr; | |
180 | sdcpwr_mapbase = ioremap(res.start, 0x1000); | |
181 | if (!sdcpwr_mapbase) { | |
182 | err = -EINVAL; | |
183 | goto out_unmap_sdcasr; | |
184 | } | |
185 | ||
186 | pr_debug("init cpufreq on CPU %d\n", policy->cpu); | |
187 | ||
12d371a6 SR |
188 | max_freqp = of_get_property(cpu, "clock-frequency", NULL); |
189 | if (!max_freqp) { | |
2e0c3370 OJ |
190 | err = -EINVAL; |
191 | goto out_unmap_sdcpwr; | |
192 | } | |
193 | ||
194 | /* we need the freq in kHz */ | |
12d371a6 | 195 | max_freq = *max_freqp / 1000; |
2e0c3370 | 196 | |
12d371a6 | 197 | pr_debug("max clock-frequency is at %u kHz\n", max_freq); |
2e0c3370 OJ |
198 | pr_debug("initializing frequency table\n"); |
199 | ||
200 | /* initialize frequency table */ | |
201 | for (i=0; pas_freqs[i].frequency!=CPUFREQ_TABLE_END; i++) { | |
50701588 VK |
202 | pas_freqs[i].frequency = |
203 | get_astate_freq(pas_freqs[i].driver_data) * 100000; | |
2e0c3370 OJ |
204 | pr_debug("%d: %d\n", i, pas_freqs[i].frequency); |
205 | } | |
206 | ||
2e0c3370 OJ |
207 | policy->cpuinfo.transition_latency = get_gizmo_latency(); |
208 | ||
209 | cur_astate = get_cur_astate(policy->cpu); | |
210 | pr_debug("current astate is at %d\n",cur_astate); | |
211 | ||
212 | policy->cur = pas_freqs[cur_astate].frequency; | |
1b095cf4 | 213 | cpumask_copy(policy->cpus, cpu_online_mask); |
2e0c3370 | 214 | |
2abb7019 OJ |
215 | ppc_proc_freq = policy->cur * 1000ul; |
216 | ||
2e0c3370 OJ |
217 | /* this ensures that policy->cpuinfo_min and policy->cpuinfo_max |
218 | * are set correctly | |
219 | */ | |
2e4633e4 | 220 | return cpufreq_table_validate_and_show(policy, pas_freqs); |
2e0c3370 OJ |
221 | |
222 | out_unmap_sdcpwr: | |
223 | iounmap(sdcpwr_mapbase); | |
224 | ||
225 | out_unmap_sdcasr: | |
226 | iounmap(sdcasr_mapbase); | |
227 | out: | |
228 | return err; | |
229 | } | |
230 | ||
231 | static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy) | |
232 | { | |
72640d88 SR |
233 | /* |
234 | * We don't support CPU hotplug. Don't unmap after the system | |
235 | * has already made it to a running state. | |
236 | */ | |
237 | if (system_state != SYSTEM_BOOTING) | |
238 | return 0; | |
239 | ||
2e0c3370 OJ |
240 | if (sdcasr_mapbase) |
241 | iounmap(sdcasr_mapbase); | |
242 | if (sdcpwr_mapbase) | |
243 | iounmap(sdcpwr_mapbase); | |
244 | ||
245 | cpufreq_frequency_table_put_attr(policy->cpu); | |
246 | return 0; | |
247 | } | |
248 | ||
2e0c3370 OJ |
249 | static int pas_cpufreq_target(struct cpufreq_policy *policy, |
250 | unsigned int target_freq, | |
251 | unsigned int relation) | |
252 | { | |
253 | struct cpufreq_freqs freqs; | |
254 | int pas_astate_new; | |
255 | int i; | |
256 | ||
257 | cpufreq_frequency_table_target(policy, | |
258 | pas_freqs, | |
259 | target_freq, | |
260 | relation, | |
261 | &pas_astate_new); | |
262 | ||
263 | freqs.old = policy->cur; | |
264 | freqs.new = pas_freqs[pas_astate_new].frequency; | |
2e0c3370 OJ |
265 | |
266 | mutex_lock(&pas_switch_mutex); | |
b43a7ffb | 267 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); |
2e0c3370 OJ |
268 | |
269 | pr_debug("setting frequency for cpu %d to %d kHz, 1/%d of max frequency\n", | |
270 | policy->cpu, | |
271 | pas_freqs[pas_astate_new].frequency, | |
50701588 | 272 | pas_freqs[pas_astate_new].driver_data); |
2e0c3370 OJ |
273 | |
274 | current_astate = pas_astate_new; | |
275 | ||
276 | for_each_online_cpu(i) | |
277 | set_astate(i, pas_astate_new); | |
278 | ||
b43a7ffb | 279 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); |
2e0c3370 OJ |
280 | mutex_unlock(&pas_switch_mutex); |
281 | ||
2abb7019 | 282 | ppc_proc_freq = freqs.new * 1000ul; |
2e0c3370 OJ |
283 | return 0; |
284 | } | |
285 | ||
286 | static struct cpufreq_driver pas_cpufreq_driver = { | |
287 | .name = "pas-cpufreq", | |
2e0c3370 OJ |
288 | .flags = CPUFREQ_CONST_LOOPS, |
289 | .init = pas_cpufreq_cpu_init, | |
290 | .exit = pas_cpufreq_cpu_exit, | |
57174310 | 291 | .verify = cpufreq_generic_frequency_table_verify, |
2e0c3370 | 292 | .target = pas_cpufreq_target, |
57174310 | 293 | .attr = cpufreq_generic_attr, |
2e0c3370 OJ |
294 | }; |
295 | ||
296 | /* | |
297 | * module init and destoy | |
298 | */ | |
299 | ||
300 | static int __init pas_cpufreq_init(void) | |
301 | { | |
71a157e8 GL |
302 | if (!of_machine_is_compatible("PA6T-1682M") && |
303 | !of_machine_is_compatible("pasemi,pwrficient")) | |
2e0c3370 OJ |
304 | return -ENODEV; |
305 | ||
306 | return cpufreq_register_driver(&pas_cpufreq_driver); | |
307 | } | |
308 | ||
309 | static void __exit pas_cpufreq_exit(void) | |
310 | { | |
311 | cpufreq_unregister_driver(&pas_cpufreq_driver); | |
312 | } | |
313 | ||
314 | module_init(pas_cpufreq_init); | |
315 | module_exit(pas_cpufreq_exit); | |
316 | ||
317 | MODULE_LICENSE("GPL"); | |
318 | MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>, Olof Johansson <olof@lixom.net>"); |