diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/cpu/cpufreq/powernow-k6.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/i386/kernel/cpu/cpufreq/powernow-k6.c')
-rw-r--r-- | arch/i386/kernel/cpu/cpufreq/powernow-k6.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/arch/i386/kernel/cpu/cpufreq/powernow-k6.c b/arch/i386/kernel/cpu/cpufreq/powernow-k6.c new file mode 100644 index 000000000000..222f8cfe3c57 --- /dev/null +++ b/arch/i386/kernel/cpu/cpufreq/powernow-k6.c | |||
@@ -0,0 +1,256 @@ | |||
1 | /* | ||
2 | * This file was based upon code in Powertweak Linux (http://powertweak.sf.net) | ||
3 | * (C) 2000-2003 Dave Jones, Arjan van de Ven, Janne Pänkälä, Dominik Brodowski. | ||
4 | * | ||
5 | * Licensed under the terms of the GNU GPL License version 2. | ||
6 | * | ||
7 | * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous* | ||
8 | */ | ||
9 | |||
10 | #include <linux/kernel.h> | ||
11 | #include <linux/module.h> | ||
12 | #include <linux/init.h> | ||
13 | #include <linux/cpufreq.h> | ||
14 | #include <linux/ioport.h> | ||
15 | #include <linux/slab.h> | ||
16 | |||
17 | #include <asm/msr.h> | ||
18 | #include <asm/timex.h> | ||
19 | #include <asm/io.h> | ||
20 | |||
21 | |||
22 | #define POWERNOW_IOPORT 0xfff0 /* it doesn't matter where, as long | ||
23 | as it is unused */ | ||
24 | |||
25 | static unsigned int busfreq; /* FSB, in 10 kHz */ | ||
26 | static unsigned int max_multiplier; | ||
27 | |||
28 | |||
29 | /* Clock ratio multiplied by 10 - see table 27 in AMD#23446 */ | ||
30 | static struct cpufreq_frequency_table clock_ratio[] = { | ||
31 | {45, /* 000 -> 4.5x */ 0}, | ||
32 | {50, /* 001 -> 5.0x */ 0}, | ||
33 | {40, /* 010 -> 4.0x */ 0}, | ||
34 | {55, /* 011 -> 5.5x */ 0}, | ||
35 | {20, /* 100 -> 2.0x */ 0}, | ||
36 | {30, /* 101 -> 3.0x */ 0}, | ||
37 | {60, /* 110 -> 6.0x */ 0}, | ||
38 | {35, /* 111 -> 3.5x */ 0}, | ||
39 | {0, CPUFREQ_TABLE_END} | ||
40 | }; | ||
41 | |||
42 | |||
43 | /** | ||
44 | * powernow_k6_get_cpu_multiplier - returns the current FSB multiplier | ||
45 | * | ||
46 | * Returns the current setting of the frequency multiplier. Core clock | ||
47 | * speed is frequency of the Front-Side Bus multiplied with this value. | ||
48 | */ | ||
49 | static int powernow_k6_get_cpu_multiplier(void) | ||
50 | { | ||
51 | u64 invalue = 0; | ||
52 | u32 msrval; | ||
53 | |||
54 | msrval = POWERNOW_IOPORT + 0x1; | ||
55 | wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */ | ||
56 | invalue=inl(POWERNOW_IOPORT + 0x8); | ||
57 | msrval = POWERNOW_IOPORT + 0x0; | ||
58 | wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */ | ||
59 | |||
60 | return clock_ratio[(invalue >> 5)&7].index; | ||
61 | } | ||
62 | |||
63 | |||
64 | /** | ||
65 | * powernow_k6_set_state - set the PowerNow! multiplier | ||
66 | * @best_i: clock_ratio[best_i] is the target multiplier | ||
67 | * | ||
68 | * Tries to change the PowerNow! multiplier | ||
69 | */ | ||
70 | static void powernow_k6_set_state (unsigned int best_i) | ||
71 | { | ||
72 | unsigned long outvalue=0, invalue=0; | ||
73 | unsigned long msrval; | ||
74 | struct cpufreq_freqs freqs; | ||
75 | |||
76 | if (clock_ratio[best_i].index > max_multiplier) { | ||
77 | printk(KERN_ERR "cpufreq: invalid target frequency\n"); | ||
78 | return; | ||
79 | } | ||
80 | |||
81 | freqs.old = busfreq * powernow_k6_get_cpu_multiplier(); | ||
82 | freqs.new = busfreq * clock_ratio[best_i].index; | ||
83 | freqs.cpu = 0; /* powernow-k6.c is UP only driver */ | ||
84 | |||
85 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); | ||
86 | |||
87 | /* we now need to transform best_i to the BVC format, see AMD#23446 */ | ||
88 | |||
89 | outvalue = (1<<12) | (1<<10) | (1<<9) | (best_i<<5); | ||
90 | |||
91 | msrval = POWERNOW_IOPORT + 0x1; | ||
92 | wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */ | ||
93 | invalue=inl(POWERNOW_IOPORT + 0x8); | ||
94 | invalue = invalue & 0xf; | ||
95 | outvalue = outvalue | invalue; | ||
96 | outl(outvalue ,(POWERNOW_IOPORT + 0x8)); | ||
97 | msrval = POWERNOW_IOPORT + 0x0; | ||
98 | wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */ | ||
99 | |||
100 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); | ||
101 | |||
102 | return; | ||
103 | } | ||
104 | |||
105 | |||
106 | /** | ||
107 | * powernow_k6_verify - verifies a new CPUfreq policy | ||
108 | * @policy: new policy | ||
109 | * | ||
110 | * Policy must be within lowest and highest possible CPU Frequency, | ||
111 | * and at least one possible state must be within min and max. | ||
112 | */ | ||
113 | static int powernow_k6_verify(struct cpufreq_policy *policy) | ||
114 | { | ||
115 | return cpufreq_frequency_table_verify(policy, &clock_ratio[0]); | ||
116 | } | ||
117 | |||
118 | |||
119 | /** | ||
120 | * powernow_k6_setpolicy - sets a new CPUFreq policy | ||
121 | * @policy: new policy | ||
122 | * @target_freq: the target frequency | ||
123 | * @relation: how that frequency relates to achieved frequency (CPUFREQ_RELATION_L or CPUFREQ_RELATION_H) | ||
124 | * | ||
125 | * sets a new CPUFreq policy | ||
126 | */ | ||
127 | static int powernow_k6_target (struct cpufreq_policy *policy, | ||
128 | unsigned int target_freq, | ||
129 | unsigned int relation) | ||
130 | { | ||
131 | unsigned int newstate = 0; | ||
132 | |||
133 | if (cpufreq_frequency_table_target(policy, &clock_ratio[0], target_freq, relation, &newstate)) | ||
134 | return -EINVAL; | ||
135 | |||
136 | powernow_k6_set_state(newstate); | ||
137 | |||
138 | return 0; | ||
139 | } | ||
140 | |||
141 | |||
142 | static int powernow_k6_cpu_init(struct cpufreq_policy *policy) | ||
143 | { | ||
144 | unsigned int i; | ||
145 | int result; | ||
146 | |||
147 | if (policy->cpu != 0) | ||
148 | return -ENODEV; | ||
149 | |||
150 | /* get frequencies */ | ||
151 | max_multiplier = powernow_k6_get_cpu_multiplier(); | ||
152 | busfreq = cpu_khz / max_multiplier; | ||
153 | |||
154 | /* table init */ | ||
155 | for (i=0; (clock_ratio[i].frequency != CPUFREQ_TABLE_END); i++) { | ||
156 | if (clock_ratio[i].index > max_multiplier) | ||
157 | clock_ratio[i].frequency = CPUFREQ_ENTRY_INVALID; | ||
158 | else | ||
159 | clock_ratio[i].frequency = busfreq * clock_ratio[i].index; | ||
160 | } | ||
161 | |||
162 | /* cpuinfo and default policy values */ | ||
163 | policy->governor = CPUFREQ_DEFAULT_GOVERNOR; | ||
164 | policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; | ||
165 | policy->cur = busfreq * max_multiplier; | ||
166 | |||
167 | result = cpufreq_frequency_table_cpuinfo(policy, clock_ratio); | ||
168 | if (result) | ||
169 | return (result); | ||
170 | |||
171 | cpufreq_frequency_table_get_attr(clock_ratio, policy->cpu); | ||
172 | |||
173 | return 0; | ||
174 | } | ||
175 | |||
176 | |||
177 | static int powernow_k6_cpu_exit(struct cpufreq_policy *policy) | ||
178 | { | ||
179 | unsigned int i; | ||
180 | for (i=0; i<8; i++) { | ||
181 | if (i==max_multiplier) | ||
182 | powernow_k6_set_state(i); | ||
183 | } | ||
184 | cpufreq_frequency_table_put_attr(policy->cpu); | ||
185 | return 0; | ||
186 | } | ||
187 | |||
188 | static unsigned int powernow_k6_get(unsigned int cpu) | ||
189 | { | ||
190 | return busfreq * powernow_k6_get_cpu_multiplier(); | ||
191 | } | ||
192 | |||
193 | static struct freq_attr* powernow_k6_attr[] = { | ||
194 | &cpufreq_freq_attr_scaling_available_freqs, | ||
195 | NULL, | ||
196 | }; | ||
197 | |||
198 | static struct cpufreq_driver powernow_k6_driver = { | ||
199 | .verify = powernow_k6_verify, | ||
200 | .target = powernow_k6_target, | ||
201 | .init = powernow_k6_cpu_init, | ||
202 | .exit = powernow_k6_cpu_exit, | ||
203 | .get = powernow_k6_get, | ||
204 | .name = "powernow-k6", | ||
205 | .owner = THIS_MODULE, | ||
206 | .attr = powernow_k6_attr, | ||
207 | }; | ||
208 | |||
209 | |||
210 | /** | ||
211 | * powernow_k6_init - initializes the k6 PowerNow! CPUFreq driver | ||
212 | * | ||
213 | * Initializes the K6 PowerNow! support. Returns -ENODEV on unsupported | ||
214 | * devices, -EINVAL or -ENOMEM on problems during initiatization, and zero | ||
215 | * on success. | ||
216 | */ | ||
217 | static int __init powernow_k6_init(void) | ||
218 | { | ||
219 | struct cpuinfo_x86 *c = cpu_data; | ||
220 | |||
221 | if ((c->x86_vendor != X86_VENDOR_AMD) || (c->x86 != 5) || | ||
222 | ((c->x86_model != 12) && (c->x86_model != 13))) | ||
223 | return -ENODEV; | ||
224 | |||
225 | if (!request_region(POWERNOW_IOPORT, 16, "PowerNow!")) { | ||
226 | printk("cpufreq: PowerNow IOPORT region already used.\n"); | ||
227 | return -EIO; | ||
228 | } | ||
229 | |||
230 | if (cpufreq_register_driver(&powernow_k6_driver)) { | ||
231 | release_region (POWERNOW_IOPORT, 16); | ||
232 | return -EINVAL; | ||
233 | } | ||
234 | |||
235 | return 0; | ||
236 | } | ||
237 | |||
238 | |||
239 | /** | ||
240 | * powernow_k6_exit - unregisters AMD K6-2+/3+ PowerNow! support | ||
241 | * | ||
242 | * Unregisters AMD K6-2+ / K6-3+ PowerNow! support. | ||
243 | */ | ||
244 | static void __exit powernow_k6_exit(void) | ||
245 | { | ||
246 | cpufreq_unregister_driver(&powernow_k6_driver); | ||
247 | release_region (POWERNOW_IOPORT, 16); | ||
248 | } | ||
249 | |||
250 | |||
251 | MODULE_AUTHOR ("Arjan van de Ven <arjanv@redhat.com>, Dave Jones <davej@codemonkey.org.uk>, Dominik Brodowski <linux@brodo.de>"); | ||
252 | MODULE_DESCRIPTION ("PowerNow! driver for AMD K6-2+ / K6-3+ processors."); | ||
253 | MODULE_LICENSE ("GPL"); | ||
254 | |||
255 | module_init(powernow_k6_init); | ||
256 | module_exit(powernow_k6_exit); | ||