blob: b9a444e358b5cfeb25da13739b374d02124cf011 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * This file was based upon code in Powertweak Linux (http://powertweak.sf.net)
Dave Jones14a66502009-01-18 00:00:04 -05003 * (C) 2000-2003 Dave Jones, Arjan van de Ven, Janne Pänkälä,
4 * Dominik Brodowski.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 *
6 * Licensed under the terms of the GNU GPL License version 2.
7 *
8 * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*
9 */
10
11#include <linux/kernel.h>
Dave Jones32ee8c32006-02-28 00:43:23 -050012#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/init.h>
14#include <linux/cpufreq.h>
15#include <linux/ioport.h>
Paolo Ciarrocchi8d2d2052008-07-28 21:08:16 +020016#include <linux/timex.h>
17#include <linux/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018
Andi Kleenfa8031a2012-01-26 00:09:12 +010019#include <asm/cpu_device_id.h>
Dave Jones14a66502009-01-18 00:00:04 -050020#include <asm/msr.h>
21
Paolo Ciarrocchi8d2d2052008-07-28 21:08:16 +020022#define POWERNOW_IOPORT 0xfff0 /* it doesn't matter where, as long
23 as it is unused */
Linus Torvalds1da177e2005-04-16 15:20:36 -070024
Dave Jones14a66502009-01-18 00:00:04 -050025#define PFX "powernow-k6: "
Linus Torvalds1da177e2005-04-16 15:20:36 -070026static unsigned int busfreq; /* FSB, in 10 kHz */
27static unsigned int max_multiplier;
28
Mikulas Patockad82b9222013-12-11 19:38:53 -050029static unsigned int param_busfreq = 0;
30static unsigned int param_max_multiplier = 0;
31
32module_param_named(max_multiplier, param_max_multiplier, uint, S_IRUGO);
33MODULE_PARM_DESC(max_multiplier, "Maximum multiplier (allowed values: 20 30 35 40 45 50 55 60)");
34
35module_param_named(bus_frequency, param_busfreq, uint, S_IRUGO);
36MODULE_PARM_DESC(bus_frequency, "Bus frequency in kHz");
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38/* Clock ratio multiplied by 10 - see table 27 in AMD#23446 */
39static struct cpufreq_frequency_table clock_ratio[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 {60, /* 110 -> 6.0x */ 0},
Mikulas Patocka22c73792013-12-11 19:39:19 -050041 {55, /* 011 -> 5.5x */ 0},
42 {50, /* 001 -> 5.0x */ 0},
43 {45, /* 000 -> 4.5x */ 0},
44 {40, /* 010 -> 4.0x */ 0},
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 {35, /* 111 -> 3.5x */ 0},
Mikulas Patocka22c73792013-12-11 19:39:19 -050046 {30, /* 101 -> 3.0x */ 0},
47 {20, /* 100 -> 2.0x */ 0},
Linus Torvalds1da177e2005-04-16 15:20:36 -070048 {0, CPUFREQ_TABLE_END}
49};
50
Mikulas Patocka22c73792013-12-11 19:39:19 -050051static const u8 index_to_register[8] = { 6, 3, 1, 0, 2, 7, 5, 4 };
52static const u8 register_to_index[8] = { 3, 2, 4, 1, 7, 6, 0, 5 };
53
Mikulas Patockad82b9222013-12-11 19:38:53 -050054static const struct {
55 unsigned freq;
56 unsigned mult;
57} usual_frequency_table[] = {
58 { 400000, 40 }, // 100 * 4
59 { 450000, 45 }, // 100 * 4.5
60 { 475000, 50 }, // 95 * 5
61 { 500000, 50 }, // 100 * 5
62 { 506250, 45 }, // 112.5 * 4.5
63 { 533500, 55 }, // 97 * 5.5
64 { 550000, 55 }, // 100 * 5.5
65 { 562500, 50 }, // 112.5 * 5
66 { 570000, 60 }, // 95 * 6
67 { 600000, 60 }, // 100 * 6
68 { 618750, 55 }, // 112.5 * 5.5
69 { 660000, 55 }, // 120 * 5.5
70 { 675000, 60 }, // 112.5 * 6
71 { 720000, 60 }, // 120 * 6
72};
73
74#define FREQ_RANGE 3000
Linus Torvalds1da177e2005-04-16 15:20:36 -070075
76/**
77 * powernow_k6_get_cpu_multiplier - returns the current FSB multiplier
78 *
Mikulas Patockae20e1d02013-12-11 19:38:32 -050079 * Returns the current setting of the frequency multiplier. Core clock
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 * speed is frequency of the Front-Side Bus multiplied with this value.
81 */
82static int powernow_k6_get_cpu_multiplier(void)
83{
Mikulas Patockae20e1d02013-12-11 19:38:32 -050084 unsigned long invalue = 0;
Dave Jones14a66502009-01-18 00:00:04 -050085 u32 msrval;
Dave Jones32ee8c32006-02-28 00:43:23 -050086
Mikulas Patockae20e1d02013-12-11 19:38:32 -050087 local_irq_disable();
88
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 msrval = POWERNOW_IOPORT + 0x1;
90 wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */
Paolo Ciarrocchi8d2d2052008-07-28 21:08:16 +020091 invalue = inl(POWERNOW_IOPORT + 0x8);
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 msrval = POWERNOW_IOPORT + 0x0;
93 wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */
94
Mikulas Patockae20e1d02013-12-11 19:38:32 -050095 local_irq_enable();
96
Mikulas Patocka22c73792013-12-11 19:39:19 -050097 return clock_ratio[register_to_index[(invalue >> 5)&7]].driver_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -070098}
99
Mikulas Patockae20e1d02013-12-11 19:38:32 -0500100static void powernow_k6_set_cpu_multiplier(unsigned int best_i)
101{
102 unsigned long outvalue, invalue;
103 unsigned long msrval;
104 unsigned long cr0;
105
106 /* we now need to transform best_i to the BVC format, see AMD#23446 */
107
108 /*
109 * The processor doesn't respond to inquiry cycles while changing the
110 * frequency, so we must disable cache.
111 */
112 local_irq_disable();
113 cr0 = read_cr0();
114 write_cr0(cr0 | X86_CR0_CD);
115 wbinvd();
116
Mikulas Patocka22c73792013-12-11 19:39:19 -0500117 outvalue = (1<<12) | (1<<10) | (1<<9) | (index_to_register[best_i]<<5);
Mikulas Patockae20e1d02013-12-11 19:38:32 -0500118
119 msrval = POWERNOW_IOPORT + 0x1;
120 wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */
121 invalue = inl(POWERNOW_IOPORT + 0x8);
122 invalue = invalue & 0x1f;
123 outvalue = outvalue | invalue;
124 outl(outvalue, (POWERNOW_IOPORT + 0x8));
125 msrval = POWERNOW_IOPORT + 0x0;
126 wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */
127
128 write_cr0(cr0);
129 local_irq_enable();
130}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131
132/**
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530133 * powernow_k6_target - set the PowerNow! multiplier
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 * @best_i: clock_ratio[best_i] is the target multiplier
135 *
136 * Tries to change the PowerNow! multiplier
137 */
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530138static int powernow_k6_target(struct cpufreq_policy *policy,
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530139 unsigned int best_i)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140{
Dave Jones14a66502009-01-18 00:00:04 -0500141 struct cpufreq_freqs freqs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
Viresh Kumar50701582013-03-30 16:25:15 +0530143 if (clock_ratio[best_i].driver_data > max_multiplier) {
Dave Jones14a66502009-01-18 00:00:04 -0500144 printk(KERN_ERR PFX "invalid target frequency\n");
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530145 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 }
147
148 freqs.old = busfreq * powernow_k6_get_cpu_multiplier();
Viresh Kumar50701582013-03-30 16:25:15 +0530149 freqs.new = busfreq * clock_ratio[best_i].driver_data;
Dave Jones32ee8c32006-02-28 00:43:23 -0500150
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530151 cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152
Mikulas Patockae20e1d02013-12-11 19:38:32 -0500153 powernow_k6_set_cpu_multiplier(best_i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530155 cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 return 0;
158}
159
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160static int powernow_k6_cpu_init(struct cpufreq_policy *policy)
161{
Dave Jones14a66502009-01-18 00:00:04 -0500162 unsigned int i, f;
Mikulas Patockad82b9222013-12-11 19:38:53 -0500163 unsigned khz;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164
165 if (policy->cpu != 0)
166 return -ENODEV;
167
Mikulas Patockad82b9222013-12-11 19:38:53 -0500168 max_multiplier = 0;
169 khz = cpu_khz;
170 for (i = 0; i < ARRAY_SIZE(usual_frequency_table); i++) {
171 if (khz >= usual_frequency_table[i].freq - FREQ_RANGE &&
172 khz <= usual_frequency_table[i].freq + FREQ_RANGE) {
173 khz = usual_frequency_table[i].freq;
174 max_multiplier = usual_frequency_table[i].mult;
175 break;
176 }
177 }
178 if (param_max_multiplier) {
179 for (i = 0; (clock_ratio[i].frequency != CPUFREQ_TABLE_END); i++) {
180 if (clock_ratio[i].driver_data == param_max_multiplier) {
181 max_multiplier = param_max_multiplier;
182 goto have_max_multiplier;
183 }
184 }
185 printk(KERN_ERR "powernow-k6: invalid max_multiplier parameter, valid parameters 20, 30, 35, 40, 45, 50, 55, 60\n");
186 return -EINVAL;
187 }
188
189 if (!max_multiplier) {
190 printk(KERN_WARNING "powernow-k6: unknown frequency %u, cannot determine current multiplier\n", khz);
191 printk(KERN_WARNING "powernow-k6: use module parameters max_multiplier and bus_frequency\n");
192 return -EOPNOTSUPP;
193 }
194
195have_max_multiplier:
196 param_max_multiplier = max_multiplier;
197
198 if (param_busfreq) {
199 if (param_busfreq >= 50000 && param_busfreq <= 150000) {
200 busfreq = param_busfreq / 10;
201 goto have_busfreq;
202 }
203 printk(KERN_ERR "powernow-k6: invalid bus_frequency parameter, allowed range 50000 - 150000 kHz\n");
204 return -EINVAL;
205 }
206
207 busfreq = khz / max_multiplier;
208have_busfreq:
209 param_busfreq = busfreq * 10;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
211 /* table init */
Paolo Ciarrocchi8d2d2052008-07-28 21:08:16 +0200212 for (i = 0; (clock_ratio[i].frequency != CPUFREQ_TABLE_END); i++) {
Viresh Kumar50701582013-03-30 16:25:15 +0530213 f = clock_ratio[i].driver_data;
Dave Jones14a66502009-01-18 00:00:04 -0500214 if (f > max_multiplier)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 clock_ratio[i].frequency = CPUFREQ_ENTRY_INVALID;
216 else
Dave Jones14a66502009-01-18 00:00:04 -0500217 clock_ratio[i].frequency = busfreq * f;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 }
219
220 /* cpuinfo and default policy values */
Mikulas Patockae20e1d02013-12-11 19:38:32 -0500221 policy->cpuinfo.transition_latency = 500000;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
Viresh Kumarb1474052013-09-16 18:56:27 +0530223 return cpufreq_table_validate_and_show(policy, clock_ratio);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224}
225
226
227static int powernow_k6_cpu_exit(struct cpufreq_policy *policy)
228{
229 unsigned int i;
Paolo Ciarrocchi8d2d2052008-07-28 21:08:16 +0200230 for (i = 0; i < 8; i++) {
231 if (i == max_multiplier)
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530232 powernow_k6_target(policy, i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 }
234 cpufreq_frequency_table_put_attr(policy->cpu);
Dave Jones32ee8c32006-02-28 00:43:23 -0500235 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236}
237
238static unsigned int powernow_k6_get(unsigned int cpu)
239{
Dave Jones14a66502009-01-18 00:00:04 -0500240 unsigned int ret;
241 ret = (busfreq * powernow_k6_get_cpu_multiplier());
242 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243}
244
Linus Torvalds221dee22007-02-26 14:55:48 -0800245static struct cpufreq_driver powernow_k6_driver = {
Viresh Kumard63bd272013-10-03 20:28:17 +0530246 .verify = cpufreq_generic_frequency_table_verify,
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530247 .target_index = powernow_k6_target,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 .init = powernow_k6_cpu_init,
249 .exit = powernow_k6_cpu_exit,
250 .get = powernow_k6_get,
251 .name = "powernow-k6",
Viresh Kumard63bd272013-10-03 20:28:17 +0530252 .attr = cpufreq_generic_attr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253};
254
Andi Kleenfa8031a2012-01-26 00:09:12 +0100255static const struct x86_cpu_id powernow_k6_ids[] = {
256 { X86_VENDOR_AMD, 5, 12 },
257 { X86_VENDOR_AMD, 5, 13 },
258 {}
259};
Ben Hutchingsb4d2d232012-02-11 23:04:12 +0000260MODULE_DEVICE_TABLE(x86cpu, powernow_k6_ids);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261
262/**
263 * powernow_k6_init - initializes the k6 PowerNow! CPUFreq driver
264 *
265 * Initializes the K6 PowerNow! support. Returns -ENODEV on unsupported
266 * devices, -EINVAL or -ENOMEM on problems during initiatization, and zero
267 * on success.
268 */
269static int __init powernow_k6_init(void)
Dave Jones32ee8c32006-02-28 00:43:23 -0500270{
Andi Kleenfa8031a2012-01-26 00:09:12 +0100271 if (!x86_match_cpu(powernow_k6_ids))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 return -ENODEV;
273
274 if (!request_region(POWERNOW_IOPORT, 16, "PowerNow!")) {
Dave Jones14a66502009-01-18 00:00:04 -0500275 printk(KERN_INFO PFX "PowerNow IOPORT region already used.\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 return -EIO;
277 }
278
279 if (cpufreq_register_driver(&powernow_k6_driver)) {
Paolo Ciarrocchi8d2d2052008-07-28 21:08:16 +0200280 release_region(POWERNOW_IOPORT, 16);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 return -EINVAL;
282 }
283
284 return 0;
285}
286
287
288/**
289 * powernow_k6_exit - unregisters AMD K6-2+/3+ PowerNow! support
290 *
291 * Unregisters AMD K6-2+ / K6-3+ PowerNow! support.
292 */
293static void __exit powernow_k6_exit(void)
294{
295 cpufreq_unregister_driver(&powernow_k6_driver);
Paolo Ciarrocchi8d2d2052008-07-28 21:08:16 +0200296 release_region(POWERNOW_IOPORT, 16);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297}
298
299
Dave Jones14a66502009-01-18 00:00:04 -0500300MODULE_AUTHOR("Arjan van de Ven, Dave Jones <davej@redhat.com>, "
301 "Dominik Brodowski <linux@brodo.de>");
Paolo Ciarrocchi8d2d2052008-07-28 21:08:16 +0200302MODULE_DESCRIPTION("PowerNow! driver for AMD K6-2+ / K6-3+ processors.");
303MODULE_LICENSE("GPL");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304
305module_init(powernow_k6_init);
306module_exit(powernow_k6_exit);