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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 | /* * Intel SpeedStep SMI driver. * * (C) 2003 Hiroshi Miura <miura@da-cha.org> * * Licensed under the terms of the GNU GPL License version 2. * */ /********************************************************************* * SPEEDSTEP - DEFINITIONS * *********************************************************************/ #include <linux/kernel.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/init.h> #include <linux/cpufreq.h> #include <linux/pci.h> #include <linux/slab.h> #include <linux/delay.h> #include <asm/ist.h> #include "speedstep-lib.h" #define PFX "speedstep-smi: " /* speedstep system management interface port/command. * * These parameters are got from IST-SMI BIOS call. * If user gives it, these are used. * */ static int smi_port = 0; static int smi_cmd = 0; static unsigned int smi_sig = 0; /* info about the processor */ static unsigned int speedstep_processor = 0; /* * There are only two frequency states for each processor. Values * are in kHz for the time being. */ static struct cpufreq_frequency_table speedstep_freqs[] = { {SPEEDSTEP_HIGH, 0}, {SPEEDSTEP_LOW, 0}, {0, CPUFREQ_TABLE_END}, }; #define GET_SPEEDSTEP_OWNER 0 #define GET_SPEEDSTEP_STATE 1 #define SET_SPEEDSTEP_STATE 2 #define GET_SPEEDSTEP_FREQS 4 /* how often shall the SMI call be tried if it failed, e.g. because * of DMA activity going on? */ #define SMI_TRIES 5 /* DEBUG * Define it if you want verbose debug output, e.g. for bug reporting */ //#define SPEEDSTEP_DEBUG #ifdef SPEEDSTEP_DEBUG #define dprintk(msg...) printk(msg) #else #define dprintk(msg...) do { } while(0) #endif /** * speedstep_smi_ownership */ static int speedstep_smi_ownership (void) { u32 command, result, magic; u32 function = GET_SPEEDSTEP_OWNER; unsigned char magic_data[] = "Copyright (c) 1999 Intel Corporation"; command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff); magic = virt_to_phys(magic_data); __asm__ __volatile__( "out %%al, (%%dx)\n" : "=D" (result) : "a" (command), "b" (function), "c" (0), "d" (smi_port), "D" (0), "S" (magic) ); return result; } /** * speedstep_smi_get_freqs - get SpeedStep preferred & current freq. * @low: the low frequency value is placed here * @high: the high frequency value is placed here * * Only available on later SpeedStep-enabled systems, returns false results or * even hangs [cf. bugme.osdl.org # 1422] on earlier systems. Empirical testing * shows that the latter occurs if !(ist_info.event & 0xFFFF). */ static int speedstep_smi_get_freqs (unsigned int *low, unsigned int *high) { u32 command, result, edi, high_mhz, low_mhz; u32 state=0; u32 function = GET_SPEEDSTEP_FREQS; if (!(ist_info.event & 0xFFFF)) return -ENODEV; command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff); __asm__ __volatile__("movl $0, %%edi\n" "out %%al, (%%dx)\n" : "=a" (result), "=b" (high_mhz), "=c" (low_mhz), "=d" (state), "=D" (edi) : "a" (command), "b" (function), "c" (state), "d" (smi_port), "S" (0) ); *high = high_mhz * 1000; *low = low_mhz * 1000; return result; } /** * speedstep_get_state - set the SpeedStep state * @state: processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH) * */ static int speedstep_get_state (void) { u32 function=GET_SPEEDSTEP_STATE; u32 result, state, edi, command; command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff); __asm__ __volatile__("movl $0, %%edi\n" "out %%al, (%%dx)\n" : "=a" (result), "=b" (state), "=D" (edi) : "a" (command), "b" (function), "c" (0), "d" (smi_port), "S" (0) ); return (state & 1); } /** * speedstep_set_state - set the SpeedStep state * @state: new processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH) * */ static void speedstep_set_state (unsigned int state) { unsigned int result = 0, command, new_state; unsigned long flags; unsigned int function=SET_SPEEDSTEP_STATE; unsigned int retry = 0; if (state > 0x1) return; /* Disable IRQs */ local_irq_save(flags); command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff); do { if (retry) { dprintk(KERN_INFO "cpufreq: retry %u, previous result %u\n", retry, result); mdelay(retry * 50); } retry++; __asm__ __volatile__( "movl $0, %%edi\n" "out %%al, (%%dx)\n" : "=b" (new_state), "=D" (result) : "a" (command), "b" (function), "c" (state), "d" (smi_port), "S" (0) ); } while ((new_state != state) && (retry <= SMI_TRIES)); /* enable IRQs */ local_irq_restore(flags); if (new_state == state) { dprintk(KERN_INFO "cpufreq: change to %u MHz succeeded after %u tries with result %u\n", (freqs.new / 1000), retry, result); } else { printk(KERN_ERR "cpufreq: change failed with new_state %u and result %u\n", new_state, result); } return; } /** * speedstep_target - set a new CPUFreq policy * @policy: new policy * @target_freq: new freq * @relation: * * Sets a new CPUFreq policy/freq. */ static int speedstep_target (struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) { unsigned int newstate = 0; struct cpufreq_freqs freqs; if (cpufreq_frequency_table_target(policy, &speedstep_freqs[0], target_freq, relation, &newstate)) return -EINVAL; freqs.old = speedstep_freqs[speedstep_get_state()].frequency; freqs.new = speedstep_freqs[newstate].frequency; freqs.cpu = 0; /* speedstep.c is UP only driver */ if (freqs.old == freqs.new) return 0; cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); speedstep_set_state(newstate); cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); return 0; } /** * speedstep_verify - verifies a new CPUFreq policy * @policy: new policy * * Limit must be within speedstep_low_freq and speedstep_high_freq, with * at least one border included. */ static int speedstep_verify (struct cpufreq_policy *policy) { return cpufreq_frequency_table_verify(policy, &speedstep_freqs[0]); } static int speedstep_cpu_init(struct cpufreq_policy *policy) { int result; unsigned int speed,state; /* capability check */ if (policy->cpu != 0) return -ENODEV; result = speedstep_smi_ownership(); if (result) { dprintk(KERN_INFO "cpufreq: fails an aquiring ownership of a SMI interface.\n"); return -EINVAL; } /* detect low and high frequency */ result = speedstep_smi_get_freqs(&speedstep_freqs[SPEEDSTEP_LOW].frequency, &speedstep_freqs[SPEEDSTEP_HIGH].frequency); if (result) { /* fall back to speedstep_lib.c dection mechanism: try both states out */ dprintk(KERN_INFO PFX "could not detect low and high frequencies by SMI call.\n"); if (!speedstep_processor) speedstep_processor = speedstep_detect_processor(); if (!speedstep_processor) return -ENODEV; result = speedstep_get_freqs(speedstep_processor, &speedstep_freqs[SPEEDSTEP_LOW].frequency, &speedstep_freqs[SPEEDSTEP_HIGH].frequency, &speedstep_set_state); if (result) { dprintk(KERN_INFO PFX "could not detect two different speeds -- aborting.\n"); return result; } else dprintk(KERN_INFO PFX "workaround worked.\n"); } /* get current speed setting */ state = speedstep_get_state(); speed = speedstep_freqs[state].frequency; dprintk(KERN_INFO "cpufreq: currently at %s speed setting - %i MHz\n", (speed == speedstep_freqs[SPEEDSTEP_LOW].frequency) ? "low" : "high", (speed / 1000)); /* cpuinfo and default policy values */ policy->governor = CPUFREQ_DEFAULT_GOVERNOR; policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; policy->cur = speed; result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs); if (result) return (result); cpufreq_frequency_table_get_attr(speedstep_freqs, policy->cpu); return 0; } static int speedstep_cpu_exit(struct cpufreq_policy *policy) { cpufreq_frequency_table_put_attr(policy->cpu); return 0; } static unsigned int speedstep_get(unsigned int cpu) { if (cpu) return -ENODEV; if (!speedstep_processor) speedstep_processor = speedstep_detect_processor(); if (!speedstep_processor) return 0; return speedstep_get_processor_frequency(speedstep_processor); } static int speedstep_resume(struct cpufreq_policy *policy) { int result = speedstep_smi_ownership(); if (result) dprintk(KERN_INFO "cpufreq: fails an aquiring ownership of a SMI interface.\n"); return result; } static struct freq_attr* speedstep_attr[] = { &cpufreq_freq_attr_scaling_available_freqs, NULL, }; static struct cpufreq_driver speedstep_driver = { .name = "speedstep-smi", .verify = speedstep_verify, .target = speedstep_target, .init = speedstep_cpu_init, .exit = speedstep_cpu_exit, .get = speedstep_get, .resume = speedstep_resume, .owner = THIS_MODULE, .attr = speedstep_attr, }; /** * speedstep_init - initializes the SpeedStep CPUFreq driver * * Initializes the SpeedStep support. Returns -ENODEV on unsupported * BIOS, -EINVAL on problems during initiatization, and zero on * success. */ static int __init speedstep_init(void) { struct cpuinfo_x86 *c = cpu_data; if (c->x86_vendor != X86_VENDOR_INTEL) { printk (KERN_INFO PFX "No Intel CPU detected.\n"); return -ENODEV; } dprintk(KERN_DEBUG PFX "signature:0x%.8lx, command:0x%.8lx, event:0x%.8lx, perf_level:0x%.8lx.\n", ist_info.signature, ist_info.command, ist_info.event, ist_info.perf_level); /* Error if no IST-SMI BIOS or no PARM sig= 'ISGE' aka 'Intel Speedstep Gate E' */ if ((ist_info.signature != 0x47534943) && ( (smi_port == 0) || (smi_cmd == 0))) return -ENODEV; if (smi_sig == 1) smi_sig = 0x47534943; else smi_sig = ist_info.signature; /* setup smi_port from MODLULE_PARM or BIOS */ if ((smi_port > 0xff) || (smi_port < 0)) { return -EINVAL; } else if (smi_port == 0) { smi_port = ist_info.command & 0xff; } if ((smi_cmd > 0xff) || (smi_cmd < 0)) { return -EINVAL; } else if (smi_cmd == 0) { smi_cmd = (ist_info.command >> 16) & 0xff; } return cpufreq_register_driver(&speedstep_driver); } /** * speedstep_exit - unregisters SpeedStep support * * Unregisters SpeedStep support. */ static void __exit speedstep_exit(void) { cpufreq_unregister_driver(&speedstep_driver); } module_param(smi_port, int, 0444); module_param(smi_cmd, int, 0444); module_param(smi_sig, uint, 0444); MODULE_PARM_DESC(smi_port, "Override the BIOS-given IST port with this value -- Intel's default setting is 0xb2"); MODULE_PARM_DESC(smi_cmd, "Override the BIOS-given IST command with this value -- Intel's default setting is 0x82"); MODULE_PARM_DESC(smi_sig, "Set to 1 to fake the IST signature when using the SMI interface."); MODULE_AUTHOR ("Hiroshi Miura"); MODULE_DESCRIPTION ("Speedstep driver for IST applet SMI interface."); MODULE_LICENSE ("GPL"); module_init(speedstep_init); module_exit(speedstep_exit); |