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 <asm/prom.h> 18 #include <asm/machdep.h> 19 #include <asm/io.h> 20 #include <asm/system.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(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 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 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 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 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 char *c, *l; 201 u32 *v; 202 203 ads = kmalloc(sizeof(struct smu_ad_sensor), GFP_KERNEL); 204 if (ads == NULL) 205 return NULL; 206 c = (char *)get_property(node, "device_type", NULL); 207 l = (char *)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 } else if (!strcmp(c, "current-sensor") && 223 !strcmp(l, "CPU Current")) { 224 ads->sens.ops = &smu_cpuamp_ops; 225 ads->sens.name = "cpu-current"; 226 } else if (!strcmp(c, "voltage-sensor") && 227 !strcmp(l, "CPU Voltage")) { 228 ads->sens.ops = &smu_cpuvolt_ops; 229 ads->sens.name = "cpu-voltage"; 230 } else if (!strcmp(c, "power-sensor") && 231 !strcmp(l, "Slots Power")) { 232 ads->sens.ops = &smu_slotspow_ops; 233 ads->sens.name = "slots-power"; 234 if (slotspow == NULL) { 235 DBG("wf: slotspow partition (%02x) not found\n", 236 SMU_SDB_SLOTSPOW_ID); 237 goto fail; 238 } 239 } else 240 goto fail; 241 242 v = (u32 *)get_property(node, "reg", NULL); 243 if (v == NULL) 244 goto fail; 245 ads->reg = *v; 246 247 if (wf_register_sensor(&ads->sens)) 248 goto fail; 249 return ads; 250 fail: 251 kfree(ads); 252 return NULL; 253 } 254 255 /* 256 * SMU Power combo sensor object 257 */ 258 259 struct smu_cpu_power_sensor { 260 struct list_head link; 261 struct wf_sensor *volts; 262 struct wf_sensor *amps; 263 int fake_volts : 1; 264 int quadratic : 1; 265 struct wf_sensor sens; 266 }; 267 #define to_smu_cpu_power(c) container_of(c, struct smu_cpu_power_sensor, sens) 268 269 static struct smu_cpu_power_sensor *smu_cpu_power; 270 271 static void smu_cpu_power_release(struct wf_sensor *sr) 272 { 273 struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr); 274 275 if (pow->volts) 276 wf_put_sensor(pow->volts); 277 if (pow->amps) 278 wf_put_sensor(pow->amps); 279 kfree(pow); 280 } 281 282 static int smu_cpu_power_get(struct wf_sensor *sr, s32 *value) 283 { 284 struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr); 285 s32 volts, amps, power; 286 u64 tmps, tmpa, tmpb; 287 int rc; 288 289 rc = pow->amps->ops->get_value(pow->amps, &s); 290 if (rc) 291 return rc; 292 293 if (pow->fake_volts) { 294 *value = amps * 12 - 0x30000; 295 return 0; 296 } 297 298 rc = pow->volts->ops->get_value(pow->volts, &volts); 299 if (rc) 300 return rc; 301 302 power = (s32)((((u64)volts) * ((u64)amps)) >> 16); 303 if (!pow->quadratic) { 304 *value = power; 305 return 0; 306 } 307 tmps = (((u64)power) * ((u64)power)) >> 16; 308 tmpa = ((u64)cpuvcp->power_quads[0]) * tmps; 309 tmpb = ((u64)cpuvcp->power_quads[1]) * ((u64)power); 310 *value = (tmpa >> 28) + (tmpb >> 28) + (cpuvcp->power_quads[2] >> 12); 311 312 return 0; 313 } 314 315 static struct wf_sensor_ops smu_cpu_power_ops = { 316 .get_value = smu_cpu_power_get, 317 .release = smu_cpu_power_release, 318 .owner = THIS_MODULE, 319 }; 320 321 322 static struct smu_cpu_power_sensor * 323 smu_cpu_power_create(struct wf_sensor *volts, struct wf_sensor *amps) 324 { 325 struct smu_cpu_power_sensor *pow; 326 327 pow = kmalloc(sizeof(struct smu_cpu_power_sensor), GFP_KERNEL); 328 if (pow == NULL) 329 return NULL; 330 pow->sens.ops = &smu_cpu_power_ops; 331 pow->sens.name = "cpu-power"; 332 333 wf_get_sensor(volts); 334 pow->volts = volts; 335 wf_get_sensor(amps); 336 pow->amps = amps; 337 338 /* Some early machines need a faked voltage */ 339 if (debugswitches && ((*debugswitches) & 0x80)) { 340 printk(KERN_INFO "windfarm: CPU Power sensor using faked" 341 " voltage !\n"); 342 pow->fake_volts = 1; 343 } else 344 pow->fake_volts = 0; 345 346 /* Try to use quadratic transforms on PowerMac8,1 and 9,1 for now, 347 * I yet have to figure out what's up with 8,2 and will have to 348 * adjust for later, unless we can 100% trust the SDB partition... 349 */ 350 if ((machine_is_compatible("PowerMac8,1") || 351 machine_is_compatible("PowerMac8,2") || 352 machine_is_compatible("PowerMac9,1")) && 353 cpuvcp_version >= 2) { 354 pow->quadratic = 1; 355 DBG("windfarm: CPU Power using quadratic transform\n"); 356 } else 357 pow->quadratic = 0; 358 359 if (wf_register_sensor(&pow->sens)) 360 goto fail; 361 return pow; 362 fail: 363 kfree(pow); 364 return NULL; 365 } 366 367 static int smu_fetch_param_partitions(void) 368 { 369 struct smu_sdbp_header *hdr; 370 371 /* Get CPU voltage/current/power calibration data */ 372 hdr = smu_get_sdb_partition(SMU_SDB_CPUVCP_ID, NULL); 373 if (hdr == NULL) { 374 DBG("wf: cpuvcp partition (%02x) not found\n", 375 SMU_SDB_CPUVCP_ID); 376 return -ENODEV; 377 } 378 cpuvcp = (struct smu_sdbp_cpuvcp *)&hdr[1]; 379 /* Keep version around */ 380 cpuvcp_version = hdr->version; 381 382 /* Get CPU diode calibration data */ 383 hdr = smu_get_sdb_partition(SMU_SDB_CPUDIODE_ID, NULL); 384 if (hdr == NULL) { 385 DBG("wf: cpudiode partition (%02x) not found\n", 386 SMU_SDB_CPUDIODE_ID); 387 return -ENODEV; 388 } 389 cpudiode = (struct smu_sdbp_cpudiode *)&hdr[1]; 390 391 /* Get slots power calibration data if any */ 392 hdr = smu_get_sdb_partition(SMU_SDB_SLOTSPOW_ID, NULL); 393 if (hdr != NULL) 394 slotspow = (struct smu_sdbp_slotspow *)&hdr[1]; 395 396 /* Get debug switches if any */ 397 hdr = smu_get_sdb_partition(SMU_SDB_DEBUG_SWITCHES_ID, NULL); 398 if (hdr != NULL) 399 debugswitches = (u8 *)&hdr[1]; 400 401 return 0; 402 } 403 404 static int __init smu_sensors_init(void) 405 { 406 struct device_node *smu, *sensors, *s; 407 struct smu_ad_sensor *volt_sensor = NULL, *curr_sensor = NULL; 408 int rc; 409 410 if (!smu_present()) 411 return -ENODEV; 412 413 /* Get parameters partitions */ 414 rc = smu_fetch_param_partitions(); 415 if (rc) 416 return rc; 417 418 smu = of_find_node_by_type(NULL, "smu"); 419 if (smu == NULL) 420 return -ENODEV; 421 422 /* Look for sensors subdir */ 423 for (sensors = NULL; 424 (sensors = of_get_next_child(smu, sensors)) != NULL;) 425 if (!strcmp(sensors->name, "sensors")) 426 break; 427 428 of_node_put(smu); 429 430 /* Create basic sensors */ 431 for (s = NULL; 432 sensors && (s = of_get_next_child(sensors, s)) != NULL;) { 433 struct smu_ad_sensor *ads; 434 435 ads = smu_ads_create(s); 436 if (ads == NULL) 437 continue; 438 list_add(&ads->link, &smu_ads); 439 /* keep track of cpu voltage & current */ 440 if (!strcmp(ads->sens.name, "cpu-voltage")) 441 volt_sensor = ads; 442 else if (!strcmp(ads->sens.name, "cpu-current")) 443 curr_sensor = ads; 444 } 445 446 of_node_put(sensors); 447 448 /* Create CPU power sensor if possible */ 449 if (volt_sensor && curr_sensor) 450 smu_cpu_power = smu_cpu_power_create(&volt_sensor->sens, 451 &curr_sensor->sens); 452 453 return 0; 454 } 455 456 static void __exit smu_sensors_exit(void) 457 { 458 struct smu_ad_sensor *ads; 459 460 /* dispose of power sensor */ 461 if (smu_cpu_power) 462 wf_unregister_sensor(&smu_cpu_power->sens); 463 464 /* dispose of basic sensors */ 465 while (!list_empty(&smu_ads)) { 466 ads = list_entry(smu_ads.next, struct smu_ad_sensor, link); 467 list_del(&ads->link); 468 wf_unregister_sensor(&ads->sens); 469 } 470 } 471 472 473 module_init(smu_sensors_init); 474 module_exit(smu_sensors_exit); 475 476 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); 477 MODULE_DESCRIPTION("SMU sensor objects for PowerMacs thermal control"); 478 MODULE_LICENSE("GPL"); 479 480