1 /* 2 * Windfarm PowerMac thermal control. SMU based sensors 3 * 4 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp. 5 * <benh@kernel.crashing.org> 6 * 7 * Released under the term of the GNU GPL v2. 8 */ 9 10 #include <linux/types.h> 11 #include <linux/errno.h> 12 #include <linux/kernel.h> 13 #include <linux/delay.h> 14 #include <linux/slab.h> 15 #include <linux/init.h> 16 #include <linux/wait.h> 17 #include <linux/completion.h> 18 #include <asm/prom.h> 19 #include <asm/machdep.h> 20 #include <asm/io.h> 21 #include <asm/sections.h> 22 #include <asm/smu.h> 23 24 #include "windfarm.h" 25 26 #define VERSION "0.2" 27 28 #undef DEBUG 29 30 #ifdef DEBUG 31 #define DBG(args...) printk(args) 32 #else 33 #define DBG(args...) do { } while(0) 34 #endif 35 36 /* 37 * Various SMU "partitions" calibration objects for which we 38 * keep pointers here for use by bits & pieces of the driver 39 */ 40 static struct smu_sdbp_cpuvcp *cpuvcp; 41 static int cpuvcp_version; 42 static struct smu_sdbp_cpudiode *cpudiode; 43 static struct smu_sdbp_slotspow *slotspow; 44 static u8 *debugswitches; 45 46 /* 47 * SMU basic sensors objects 48 */ 49 50 static LIST_HEAD(smu_ads); 51 52 struct smu_ad_sensor { 53 struct list_head link; 54 u32 reg; /* index in SMU */ 55 struct wf_sensor sens; 56 }; 57 #define to_smu_ads(c) container_of(c, struct smu_ad_sensor, sens) 58 59 static void smu_ads_release(struct wf_sensor *sr) 60 { 61 struct smu_ad_sensor *ads = to_smu_ads(sr); 62 63 kfree(ads); 64 } 65 66 static int smu_read_adc(u8 id, s32 *value) 67 { 68 struct smu_simple_cmd cmd; 69 DECLARE_COMPLETION_ONSTACK(comp); 70 int rc; 71 72 rc = smu_queue_simple(&cmd, SMU_CMD_READ_ADC, 1, 73 smu_done_complete, &comp, id); 74 if (rc) 75 return rc; 76 wait_for_completion(&comp); 77 if (cmd.cmd.status != 0) 78 return cmd.cmd.status; 79 if (cmd.cmd.reply_len != 2) { 80 printk(KERN_ERR "winfarm: read ADC 0x%x returned %d bytes !\n", 81 id, cmd.cmd.reply_len); 82 return -EIO; 83 } 84 *value = *((u16 *)cmd.buffer); 85 return 0; 86 } 87 88 static int smu_cputemp_get(struct wf_sensor *sr, s32 *value) 89 { 90 struct smu_ad_sensor *ads = to_smu_ads(sr); 91 int rc; 92 s32 val; 93 s64 scaled; 94 95 rc = smu_read_adc(ads->reg, &val); 96 if (rc) { 97 printk(KERN_ERR "windfarm: read CPU temp failed, err %d\n", 98 rc); 99 return rc; 100 } 101 102 /* Ok, we have to scale & adjust, taking units into account */ 103 scaled = (s64)(((u64)val) * (u64)cpudiode->m_value); 104 scaled >>= 3; 105 scaled += ((s64)cpudiode->b_value) << 9; 106 *value = (s32)(scaled << 1); 107 108 return 0; 109 } 110 111 static int smu_cpuamp_get(struct wf_sensor *sr, s32 *value) 112 { 113 struct smu_ad_sensor *ads = to_smu_ads(sr); 114 s32 val, scaled; 115 int rc; 116 117 rc = smu_read_adc(ads->reg, &val); 118 if (rc) { 119 printk(KERN_ERR "windfarm: read CPU current failed, err %d\n", 120 rc); 121 return rc; 122 } 123 124 /* Ok, we have to scale & adjust, taking units into account */ 125 scaled = (s32)(val * (u32)cpuvcp->curr_scale); 126 scaled += (s32)cpuvcp->curr_offset; 127 *value = scaled << 4; 128 129 return 0; 130 } 131 132 static int smu_cpuvolt_get(struct wf_sensor *sr, s32 *value) 133 { 134 struct smu_ad_sensor *ads = to_smu_ads(sr); 135 s32 val, scaled; 136 int rc; 137 138 rc = smu_read_adc(ads->reg, &val); 139 if (rc) { 140 printk(KERN_ERR "windfarm: read CPU voltage failed, err %d\n", 141 rc); 142 return rc; 143 } 144 145 /* Ok, we have to scale & adjust, taking units into account */ 146 scaled = (s32)(val * (u32)cpuvcp->volt_scale); 147 scaled += (s32)cpuvcp->volt_offset; 148 *value = scaled << 4; 149 150 return 0; 151 } 152 153 static int smu_slotspow_get(struct wf_sensor *sr, s32 *value) 154 { 155 struct smu_ad_sensor *ads = to_smu_ads(sr); 156 s32 val, scaled; 157 int rc; 158 159 rc = smu_read_adc(ads->reg, &val); 160 if (rc) { 161 printk(KERN_ERR "windfarm: read slots power failed, err %d\n", 162 rc); 163 return rc; 164 } 165 166 /* Ok, we have to scale & adjust, taking units into account */ 167 scaled = (s32)(val * (u32)slotspow->pow_scale); 168 scaled += (s32)slotspow->pow_offset; 169 *value = scaled << 4; 170 171 return 0; 172 } 173 174 175 static const struct wf_sensor_ops smu_cputemp_ops = { 176 .get_value = smu_cputemp_get, 177 .release = smu_ads_release, 178 .owner = THIS_MODULE, 179 }; 180 static const struct wf_sensor_ops smu_cpuamp_ops = { 181 .get_value = smu_cpuamp_get, 182 .release = smu_ads_release, 183 .owner = THIS_MODULE, 184 }; 185 static const struct wf_sensor_ops smu_cpuvolt_ops = { 186 .get_value = smu_cpuvolt_get, 187 .release = smu_ads_release, 188 .owner = THIS_MODULE, 189 }; 190 static const struct wf_sensor_ops smu_slotspow_ops = { 191 .get_value = smu_slotspow_get, 192 .release = smu_ads_release, 193 .owner = THIS_MODULE, 194 }; 195 196 197 static struct smu_ad_sensor *smu_ads_create(struct device_node *node) 198 { 199 struct smu_ad_sensor *ads; 200 const char *c, *l; 201 const u32 *v; 202 203 ads = kmalloc(sizeof(struct smu_ad_sensor), GFP_KERNEL); 204 if (ads == NULL) 205 return NULL; 206 c = of_get_property(node, "device_type", NULL); 207 l = of_get_property(node, "location", NULL); 208 if (c == NULL || l == NULL) 209 goto fail; 210 211 /* We currently pick the sensors based on the OF name and location 212 * properties, while Darwin uses the sensor-id's. 213 * The problem with the IDs is that they are model specific while it 214 * looks like apple has been doing a reasonably good job at keeping 215 * the names and locations consistents so I'll stick with the names 216 * and locations for now. 217 */ 218 if (!strcmp(c, "temp-sensor") && 219 !strcmp(l, "CPU T-Diode")) { 220 ads->sens.ops = &smu_cputemp_ops; 221 ads->sens.name = "cpu-temp"; 222 if (cpudiode == NULL) { 223 DBG("wf: cpudiode partition (%02x) not found\n", 224 SMU_SDB_CPUDIODE_ID); 225 goto fail; 226 } 227 } else if (!strcmp(c, "current-sensor") && 228 !strcmp(l, "CPU Current")) { 229 ads->sens.ops = &smu_cpuamp_ops; 230 ads->sens.name = "cpu-current"; 231 if (cpuvcp == NULL) { 232 DBG("wf: cpuvcp partition (%02x) not found\n", 233 SMU_SDB_CPUVCP_ID); 234 goto fail; 235 } 236 } else if (!strcmp(c, "voltage-sensor") && 237 !strcmp(l, "CPU Voltage")) { 238 ads->sens.ops = &smu_cpuvolt_ops; 239 ads->sens.name = "cpu-voltage"; 240 if (cpuvcp == NULL) { 241 DBG("wf: cpuvcp partition (%02x) not found\n", 242 SMU_SDB_CPUVCP_ID); 243 goto fail; 244 } 245 } else if (!strcmp(c, "power-sensor") && 246 !strcmp(l, "Slots Power")) { 247 ads->sens.ops = &smu_slotspow_ops; 248 ads->sens.name = "slots-power"; 249 if (slotspow == NULL) { 250 DBG("wf: slotspow partition (%02x) not found\n", 251 SMU_SDB_SLOTSPOW_ID); 252 goto fail; 253 } 254 } else 255 goto fail; 256 257 v = of_get_property(node, "reg", NULL); 258 if (v == NULL) 259 goto fail; 260 ads->reg = *v; 261 262 if (wf_register_sensor(&ads->sens)) 263 goto fail; 264 return ads; 265 fail: 266 kfree(ads); 267 return NULL; 268 } 269 270 /* 271 * SMU Power combo sensor object 272 */ 273 274 struct smu_cpu_power_sensor { 275 struct list_head link; 276 struct wf_sensor *volts; 277 struct wf_sensor *amps; 278 int fake_volts : 1; 279 int quadratic : 1; 280 struct wf_sensor sens; 281 }; 282 #define to_smu_cpu_power(c) container_of(c, struct smu_cpu_power_sensor, sens) 283 284 static struct smu_cpu_power_sensor *smu_cpu_power; 285 286 static void smu_cpu_power_release(struct wf_sensor *sr) 287 { 288 struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr); 289 290 if (pow->volts) 291 wf_put_sensor(pow->volts); 292 if (pow->amps) 293 wf_put_sensor(pow->amps); 294 kfree(pow); 295 } 296 297 static int smu_cpu_power_get(struct wf_sensor *sr, s32 *value) 298 { 299 struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr); 300 s32 volts, amps, power; 301 u64 tmps, tmpa, tmpb; 302 int rc; 303 304 rc = pow->amps->ops->get_value(pow->amps, &s); 305 if (rc) 306 return rc; 307 308 if (pow->fake_volts) { 309 *value = amps * 12 - 0x30000; 310 return 0; 311 } 312 313 rc = pow->volts->ops->get_value(pow->volts, &volts); 314 if (rc) 315 return rc; 316 317 power = (s32)((((u64)volts) * ((u64)amps)) >> 16); 318 if (!pow->quadratic) { 319 *value = power; 320 return 0; 321 } 322 tmps = (((u64)power) * ((u64)power)) >> 16; 323 tmpa = ((u64)cpuvcp->power_quads[0]) * tmps; 324 tmpb = ((u64)cpuvcp->power_quads[1]) * ((u64)power); 325 *value = (tmpa >> 28) + (tmpb >> 28) + (cpuvcp->power_quads[2] >> 12); 326 327 return 0; 328 } 329 330 static const struct wf_sensor_ops smu_cpu_power_ops = { 331 .get_value = smu_cpu_power_get, 332 .release = smu_cpu_power_release, 333 .owner = THIS_MODULE, 334 }; 335 336 337 static struct smu_cpu_power_sensor * 338 smu_cpu_power_create(struct wf_sensor *volts, struct wf_sensor *amps) 339 { 340 struct smu_cpu_power_sensor *pow; 341 342 pow = kmalloc(sizeof(struct smu_cpu_power_sensor), GFP_KERNEL); 343 if (pow == NULL) 344 return NULL; 345 pow->sens.ops = &smu_cpu_power_ops; 346 pow->sens.name = "cpu-power"; 347 348 wf_get_sensor(volts); 349 pow->volts = volts; 350 wf_get_sensor(amps); 351 pow->amps = amps; 352 353 /* Some early machines need a faked voltage */ 354 if (debugswitches && ((*debugswitches) & 0x80)) { 355 printk(KERN_INFO "windfarm: CPU Power sensor using faked" 356 " voltage !\n"); 357 pow->fake_volts = 1; 358 } else 359 pow->fake_volts = 0; 360 361 /* Try to use quadratic transforms on PowerMac8,1 and 9,1 for now, 362 * I yet have to figure out what's up with 8,2 and will have to 363 * adjust for later, unless we can 100% trust the SDB partition... 364 */ 365 if ((of_machine_is_compatible("PowerMac8,1") || 366 of_machine_is_compatible("PowerMac8,2") || 367 of_machine_is_compatible("PowerMac9,1")) && 368 cpuvcp_version >= 2) { 369 pow->quadratic = 1; 370 DBG("windfarm: CPU Power using quadratic transform\n"); 371 } else 372 pow->quadratic = 0; 373 374 if (wf_register_sensor(&pow->sens)) 375 goto fail; 376 return pow; 377 fail: 378 kfree(pow); 379 return NULL; 380 } 381 382 static void smu_fetch_param_partitions(void) 383 { 384 const struct smu_sdbp_header *hdr; 385 386 /* Get CPU voltage/current/power calibration data */ 387 hdr = smu_get_sdb_partition(SMU_SDB_CPUVCP_ID, NULL); 388 if (hdr != NULL) { 389 cpuvcp = (struct smu_sdbp_cpuvcp *)&hdr[1]; 390 /* Keep version around */ 391 cpuvcp_version = hdr->version; 392 } 393 394 /* Get CPU diode calibration data */ 395 hdr = smu_get_sdb_partition(SMU_SDB_CPUDIODE_ID, NULL); 396 if (hdr != NULL) 397 cpudiode = (struct smu_sdbp_cpudiode *)&hdr[1]; 398 399 /* Get slots power calibration data if any */ 400 hdr = smu_get_sdb_partition(SMU_SDB_SLOTSPOW_ID, NULL); 401 if (hdr != NULL) 402 slotspow = (struct smu_sdbp_slotspow *)&hdr[1]; 403 404 /* Get debug switches if any */ 405 hdr = smu_get_sdb_partition(SMU_SDB_DEBUG_SWITCHES_ID, NULL); 406 if (hdr != NULL) 407 debugswitches = (u8 *)&hdr[1]; 408 } 409 410 static int __init smu_sensors_init(void) 411 { 412 struct device_node *smu, *sensors, *s; 413 struct smu_ad_sensor *volt_sensor = NULL, *curr_sensor = NULL; 414 415 if (!smu_present()) 416 return -ENODEV; 417 418 /* Get parameters partitions */ 419 smu_fetch_param_partitions(); 420 421 smu = of_find_node_by_type(NULL, "smu"); 422 if (smu == NULL) 423 return -ENODEV; 424 425 /* Look for sensors subdir */ 426 for (sensors = NULL; 427 (sensors = of_get_next_child(smu, sensors)) != NULL;) 428 if (!strcmp(sensors->name, "sensors")) 429 break; 430 431 of_node_put(smu); 432 433 /* Create basic sensors */ 434 for (s = NULL; 435 sensors && (s = of_get_next_child(sensors, s)) != NULL;) { 436 struct smu_ad_sensor *ads; 437 438 ads = smu_ads_create(s); 439 if (ads == NULL) 440 continue; 441 list_add(&ads->link, &smu_ads); 442 /* keep track of cpu voltage & current */ 443 if (!strcmp(ads->sens.name, "cpu-voltage")) 444 volt_sensor = ads; 445 else if (!strcmp(ads->sens.name, "cpu-current")) 446 curr_sensor = ads; 447 } 448 449 of_node_put(sensors); 450 451 /* Create CPU power sensor if possible */ 452 if (volt_sensor && curr_sensor) 453 smu_cpu_power = smu_cpu_power_create(&volt_sensor->sens, 454 &curr_sensor->sens); 455 456 return 0; 457 } 458 459 static void __exit smu_sensors_exit(void) 460 { 461 struct smu_ad_sensor *ads; 462 463 /* dispose of power sensor */ 464 if (smu_cpu_power) 465 wf_unregister_sensor(&smu_cpu_power->sens); 466 467 /* dispose of basic sensors */ 468 while (!list_empty(&smu_ads)) { 469 ads = list_entry(smu_ads.next, struct smu_ad_sensor, link); 470 list_del(&ads->link); 471 wf_unregister_sensor(&ads->sens); 472 } 473 } 474 475 476 module_init(smu_sensors_init); 477 module_exit(smu_sensors_exit); 478 479 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); 480 MODULE_DESCRIPTION("SMU sensor objects for PowerMacs thermal control"); 481 MODULE_LICENSE("GPL"); 482 483